Agroforestry Lecture Notes PDF

A Lecture Note on AGROFORESTRY (HRT-406) B.SC.AG. 7TH SEMESTER Prepared By Dr. Ram Lal Sheathe Agriculture and Forestry University Department of Horticulture Rampur, Chitwan 2078/79 Course Syllabus of AGROFORESTRY B.SC.AG. 7TH SEMESTER Course Code: HRT 406 Credit Hours: 2 (1+1) Full Marks: 50 Theory: 25 Practical: 25 OBJECTIVES Upon the completion of this course the student will have basic knowledge on principles and practices of agro forestry systems I. SYLLABUS Concept of Agro-forestry: Definition, importance and scope. Roles of trees in fulfilling the basic requirements of people, characteristics of trees for Agro-forestry development and tree improvement. Agroforestry System (AFS): Classification of the Agroforestry system (AFS) and over-view of Arsine Nepal and similar agro-eco-zoning in the World. Tree-crop- interaction: Nature of interactions, factors, types, quantifying interactions. Soil management under AFS: Soil-water conservation approaches, soil-fertility management. Designing AFS: Conceptual framework for designing AFS. Project development: ICFAF’s diagnosis and design, diagnostic methods and tools used in AFS. Management of trees in AFS: Tree-management, agricultural management, silvicultural and management operations. Quantifying agroforestry products. II. COURSE OUTLINE A. Lecture S.N. Topics No of lectures 1. Concept of Agroforestry: Definition, importance and scope. 1 2. Tree selection and improvements: 2 2.1Roles of trees in fulfilling the basic requirements of people 2.2Characteristics of trees for Agroforestry development and tree improvements 3. Agroforestry system (AFS): 2 3.1Classification and over-view of Agroforestry System ( AFS) 3.2Overview of AFS in Nepal and similar agro-eco-zoning in the world 4. Tree-crop-interaction 2 4.1Factors and types on nature of tree-crop interaction 4.2Quantifying Agroforestryproducts 5. Soil management under AFS: 2 5.1Approaches of soil-water conservation 5.2Soil-fertility management 6. Designing AFS: 2 6.1Conceptual framework for designing AFS 6.2Factors affecting AFS 7. Project development: 2 7.1ICFAF’s diagnosis and design 7.2Diagnostic methods and tools used in AFS 8. Management of trees in AFS: 2 8.1 Management of trees in Agriculture 8.2 Agricultural and Silvicultural management in relation to crop Total 15 B. Practical S.N. Topics No of lectures 1. Tree selection and identification for AFS at different areas: 3 1.1 High Hills 1.2 Mid Hills 1.3 Terai 2. Practice in contour farming system 1 3. Preparation ‘A’-frames and determines contour lines 1 4. Lay-out of a soil-water conservation systems. 1 5. Nursery establishment for AFS 3 5.1 Collection and identification of seeds of Agroforesty trees 5.2 Preparation of nursery bed for Agroforestry tree Seed sowing for Agroforestry trees 6. Tree-clinic for AFS. 1 7. Training and pruning for Agro forestry trees 1 8. Height and canopy measurement for selected Agroforesty trees 1 9. Different AFS development (SALT and home garden) 1 10. Establishment of Agroforesty farm at Agriculture and Forestry 1 University (AFU) 11. A visit to success story of Agroforestry project(s) at local level 1 Total 15 REFERENCES Chaundawat, B.S. and S.K. Gautam. 1996. Text of Agroforestry. Oxfood and IBH Publishing Co. Pvt. Ltd. India. Dwivedi, A.P. 1992. Agroforestry: Principles and Practices. Oxfood and IBH Publishing Co. Pvt. Ltd. India. Prakash, Ram. 1991. Propagation Practices of Improtant Indian Trees. International Book Distributions, India. Singh, S.P. 1998. HandBook of Agroforestry.Agrotech Publishing Academy, India. Thapa, F. 2001. Nepalese Flora for Agroforestry Systems.S.B. Bhandari Publication, Nepal. Lecture Note of Agroforestry, Hort Divn, AFU, Rampur, Chitwan, By: Dr. Ram Lal Shrestha LECT 1 & 2: Concept of Agro forestry: Definition, importance and scope. INTRODUCTION, CONCEPTS, DEFINITION, IMPORTANCE AND SCOPE OF AGROFORESTRY INTRODUCTION Agro forestry, which involves integrating woody perennials in a farming system, has been a longstanding practice of Nepal (Gilmour and Nurse, 1991). Trees are integral to hill farming and have tangible impact on rural farming systems. A great diversity of tree species, often exceeding 100 species, exists in upland farms; they are scattered in and around homesteads. These trees contribute substantially to carbon stocks in the system and carbon sequestration. It is important to understand agro forestry systems and their role in carbon sequestration to formulate future strategies for national-level carbon trading and natural resource management. The major agro forestry practices in the hills of the eastern Himalayas include home gardens, agri- silviculture system (planting trees along terrace bunds, borders and slopes), silvi-pastoral system (livestock grazing in grasslands), agri-silvi-pastoral system (typical hill farming method, in which crops are grown on flat terraces, trees on terrace bunds and borders, and grasses on terrace slopes; and livestock are allowed to graze during fallow season), and alley cropping, agri-silviculture system, silvi-pastoral system, horti-silvi-culture system and aqua-silviculture. Shifting cultivation (also called slash and burn agriculture), though in decline, is still practiced in many upland areas in the region. Agro forestry has been recognized as a land-use system which is capable of yielding both wood and food at the same time conserving and rehabilitating the ecosystems. It increases the productivity and at the same time maintains the nutrient balance and as well as protect the nature. It has two major roles, the productive role and the service role. Demographic pressure, demands the food, fodder, fuel, medicines, timbers, vegetables etc. Role of Agro forestry for efficient nutrient utilization (cycling), nitrogen fixation, organic matter addition and for improving drainage. Latest forest resource assessment data reveal that out of the total land area of Nepal, forest including other wooded land comprises around 5.96 million hectares (44.74 %), 1.56 million hectares (12%) of grassland, 3.0 million (21%) of the farmland, about 1.06 million hectares (7%) of uncultivated inclusion. The data shows that the forest areas have increased nearly by 5.14 percent. (Table 1) Table 1: Land use of Nepal. Categories Area (Million hectares) Percent Forest*. 5.96 40.36 Other Wooded Land* 0.64 4.38 Grass land** 1.77 12.0 Agriculture land ** 3.09 21.0 0Non-cultivated inclusions** 1.03 7.0 Water, streams, and river beds** 0.38 2.6 Urban and industrial areas** 2.62 17.8 Total 15.49 105.14 *Source: DFRS, 2016. ** Source: GoN/MoFSC, 2014. Forest, range land, wetland, and agro-ecosystem are the major ecosystem groups of Nepal. A total of 118 ecosystems are found in Nepal. Of the five physiographic zones of the country, Middle Mountain has the maximum number of ecosystems (Table 2). Table 2: Number of ecosystems in Nepal Physiographic Zone Ecosystems Number % Terai 12 10.2 Siwalik 14 11.9 Middle Mountains 53 44 High Mountains 38 32.2 Other 1 0.8 Total 118 100 Source: GoN/MoFSC, 2014 CONCEPT OF AGROFORESTRY Agro forestry is an age old practice, and has long tradition of growing food crops, trees and animals together for producing multiple ranges of products. In fact, trees in our ancient literature that planting tree was being done by individuals on their own along with agriculture crops. Maharishi Kashyap, classifies land into several categories and identifies areas which are suitable for planting trees: all wet and dry lands and areas around houses, wells, tanks are specifically identified for tree planting. Now a days, Peoples are no longer able to meet their requirements of firewood, fodder, timber, bamboo, etc. from the forest. Due to shortage of wood the prices of these commodities are increased manifold. Many forest based industries have been facing problems in supply of raw material. Than farmers are started planting trees on their farm lands to meet these shortages along with agriculture crop; thus from the concept of agro forestry it emerged out. The concept of agro forestry is to combine both modern and traditional land use systems where trees are managed together with crops or animal production. Agro forestry is a land-use system in which trees or shrubs are grown in association with agricultural crops, pastures or livestock. Such integration of trees and shrubs in the land-use system can be either a spatial arrangement, e.g., trees growing in a field at the same time as the crop, or in a time sequence, e.g., shrubs grown on a fallow for restoration of soil fertility. AGROFORESTRY DEFINITIONS: "An efficient and integrated land use management system by raising of certain agricultural crops, forest tree species and or animals simultaneously or sequentially on the same unit of land with appropriate management practices which result in overall increase in the production, under a particular set of climatic and edaphic conditions and socio-economic status of local people." Agro forestry is relatively new name of for set of old land use practices. Many definitions have been proposed world-wide. However it has now become an accepted land use system. Some of the definitions given by different workers are as follows: Bene et al. (1977) defined "agro forestry as a sustainable management system for land that increases overall production, combines agriculture crops, forest plants and tree crop and/or animals simultaneously or sequentially and applies management practices that are compatible with the cultural patterns of a local population". King and Chandler (1978): “Agro forestry is a sustainable land management system which increases the overall yield of the land, combines the production of crops (including tree crops) and forest plants and/or animals simultaneously or sequentially, on the same unit of land and applies management practices that are compatible with the cultural practices of the local population". The International Centre for Research in Agro forestry (ICRAF, also known as the World Agro forestry Centre) suggests the following definition: "Agro forestry is a collective name for land use systems and technologies, where woody perennials (trees, shrubs, palm bamboos, etc.) are deliberately used in the same piece of land management units as agriculture crops and animals in some form of spatial arrangement or temporal sequence. In agro forestry systems, there are both ecological and economical interactions between the different components (Lundgren and Raintree, 1982), Some of the basic ideas emerging from the definition of AGROFORESTRY Agro forestry normally involves two or more species of plants (or plants and animals). An agro forestry system always has two or more outputs. The cycle of an agro forestry system always lasts more than one year. Even the simplest agro forestry system is more complex, ecologically and economically, than a mono-cropping system. In other words, agro forestry is a system of combining trees with crops (such as food, fruit, vegetables, fodder and forage) and/or livestock in a field at the same time or at different times. Objectives of Agro forestry: In all agro forestry land management there areA two essential and related aims such as The AFS should conserve and improve the site Optimize the combined production of tress, agricultural crops and animal Purpose of agro forestry To optimize overall production of food/fruits, woody crops and fodder and forage including livestock per unit area. ƒ To provide support for conservation of soil, water and other resources. ƒ To improve local environment. ƒ To enhance the socioeconomic condition of the farmers. ƒ To improve the livelihoods of the farmers. Attributes of Agro forestry: There are three attributes which, theoretically, all agro forestry system possess, these are: Productivity: Most, if not all, agro forestry systems aim to maintain or increase production (of preferred commodities as well as productivity (of the land). Agro forestry can improve productivity in many different ways. These include: increased output of tree products, improved yields of associated crops, reduction of cropping system inputs, and increased labor efficiency. Sustainability: By conserving the production potential of the resource base, mainly through the beneficial effects of woody perennials on soils, agro forestry can achieve and indefinitely maintain conservation and fertility goals Adoptability: The word “adopt” here means “accept” and it may be distinguished from another commonly used word adapt, which implies “modify” or “change.” The fact that agro forestry is a relatively new word for an old set of practices means that, in some cases, agro forestry was already been accepted by the farming community. However, the implication here is that improved or new agro forestry technologies that are introduced into new areas should also conform to local farming practices. Table 3: Distinction between Social Forestry and Agro forestry Social Forestry Agro forestry 1. Social forestry is a plantation for the benefit 1. Agro forestry is a sustainable land of rural and urban communities, with objectives management system that increases the overall to supply fuel wood to divert cow dung from production, combines agricultural crops, tree village hearths to village fields, small timber for crops and forest plants and/or animals housing and agricultural implements and fodder simultaneously or sequentially, and for cattle of the rural population, protection of applies management practices that are agriculture by creation of diverse ecosystem and compatible with the cultural patterns of the arresting wind and water erosion, provide raw local population. material for village cottage industries and improve scenic value in rural and urban areas. 2. It is thus the forestry of the people, by the 2. It is a system which is for managing the unit people and for the people. of land for maximizes production of agricultural crop and forest trees complimentary with each other. 3. Planting of trees on massive scale is done on 3. Agro forestry is practiced mostly in farmers’ vacant land, community land, roadside railway field/own land. track and even degraded reserve forest. Helps to eradicate poverty especially among land less and marginal rural people by providing them job potential. 4. Mainly trees and shrubs are to be used to 4. It involves integration of two or more than harvest multiple products. two components ion the same unit of land. 5. It is primarily a government based 5. Agro forestry involves the rural awakening programmed that aims to increase the forest area towards self sufficiency by producing by rehabilitating wastelands while producing maximum biomass per unit area, fulfilling then biomass both for industrial and local uses. needs of food, fodder and fuel wood etc.. Historical Background It is believed that Homo erectus used wood for fire at least 750,000 years ago. The oldest evidence of the use of wood for construction, found at the Kalambo Falls site in Tanzania, dates from some 60,000 years ago. Carpenters and shipwrights fabricated wooden boats as early as 2700 BCE. The National School of Forestry was established in Nancy, France, in 1825. At the end of 19th century, forest plantation has been established adopting agro forestry systems, which is known as Taungya agro forestry system. This system was first started from Burma in 1850s, where teak (Tectona grandis) plantation areas were given to shifting cultivators to grow agriculture crops. Taungya agro forestry has been adopted widely in South Asia in 1890s. In present Bengladesh, plantation was established adopting Taungya approach in between 1887 to 1890s, where as this in West Bengal of India in 1896. Agro forestry was formally outlined in the early 20th century by American economic geographer Ja. Russell Smith in his book Tree Crops: A Permanent Agriculture (1929). Smith viewed tree-based “permanent agriculture” as a solution to the destructive erosion that often followed the cultivation of sloping lands. However, his contributions were largely overlooked during the green revolution of the 1960s and the subsequent and more-inclusive farming systems research/extension (FSR/E) development approach of the early 1970s that sought sustainable agricultural alternatives. In 1977 the Canadian International Development Research Centre released a report called Trees, Food and People (part of the Project for Identification of Tropical Forestry Research Priorities) describing the critical role of trees in sustaining agricultural production in the tropics. That led to the establishment of the International Council for Research in Agro forestry (ICRAF), ultimately headquartered in Nairobi, Kenya, in 1977, and in 1982 ICRAF launched the journal Agro forestry Systems to provide a global research outlet for the newly emerging field. In 2002 ICRAF was renamed the World Agro forestry Centre to reflect its global mandate. In Nepal, Agro forestry practices in Nepal are traditional, very old, and very specific to the local social, economic and agro ecological conditions. The farmers, grazers, and forest dwellers have an intimate knowledge of these traditional practices. Agro forestry is a method of farming that allows trees and shrubs to grow along with crops and/or livestock, therefore blending agriculture and forestry in the same production system. It is a traditional practice, where fodder, fire wood and timber species are grown along terrace bunds, borders and slopes. Shifting cultivation is also found commonly in Nepal until now. Taungya agro forestry practice was first started in Nepal in 1972 in Tamagadhi of Bara district, where forest areas encroached by the hill migrants were planted and given to encroachers to grow agriculture. The main aim of this practice was to protect remaining forests from encroachment. After that Terai Community Forestry Development Project and Sagarnath Forestry Development Project have also practiced this system in large scale from 1983 to 1992. These projects have given plantation areas (generally 1 ha for one family) for poor farmers living around for 4-5 years on simple agreement to grow agriculture crops without any damage to trees. Farmers were responsible to replant seedlings when planted trees were damaged during growing crops in Taungya plots. Traditional agro forestry farming system of Nepal includes growing of trees, agriculture crops and livestock for the purpose of subsistence livelihood, which is gradually replaced by the cash crops. Farmers have started cultivating cash crops such as cardamom under Uttis (Alnus nepalensis), ginger and turmeric under tree shade and home gardens, and coffee under Ipil Ipil (Leucaena leucocephala) and shade trees, and tea under Sissoo (Dalbergia sissoo) and Siris (Albezzia spp), vegetables, and fruits (orange, banana, papaya, mango, apple etc) for commercial purposes. These changes in crops and cropping pattern have changed the agricultural landscape and environment resulting to agricultural evolution. Nepal Agricultural Research Council (NARC), Department of Forest Research and Survey (DFRS), Nepal Agro forestry Foundation (NAF)/ Kathmandu Forestry College (KAFCOL), Institute of Forestry (IOF) and other I/NGOs are promoting agro forestry research and extension work in Nepal. IMPORTANCE OF AGROFORESTRY 1. It can help to increase food production and boost food security. Generally, trees can provide nutritious fruits, nuts, and leaves for consumption in households and helps to improve the health and nutrition status of people. 2. Felled trees and their residues can be used as wood energy for cooking and heating while leaves can be used as forage for livestock. 3. It also supports the production of a wide range of products such as timber, fiber, fodder and forage, craft products, medicinal products, hedging materials, and gums and resins among others. 4. Trees can block strong winds, protecting crops from damage. Some crops like barley, alfalfa, and winter wheat are also known to thrive under shelter. 5. Trees also protect animals from wind chill in cold days while also providing shade on hot days and thus, helping lower animal stress. 6. Trees can also be a source of medicines and natural remedies. 7. Agro forestry helps to reduce the vulnerabilities associated with agricultural production and even improve the recovery after natural disasters, hazards, or socioeconomic downturns and reducing the risk of economic failure. 8. Agro forestry can strengthen the soil structure; mitigating soil erosions, improving soil fertility, and preventing possible landslides. 9. Agro forestry can bring forth sustained employment and higher income, which leads to an improvement in rural living standards. 10. Growing trees in agricultural systems can reduce the impact of climate change on agriculture. 11. The roots of trees can strengthen the soil structure; mitigating soil erosions, improving soil fertility, and preventing erosion, and landslides. 12. Agro forestry can help protect the natural resources in the environment. For example, growing trees can help improve the quality of water and its quantity by filtering and capturing of water resources. 13. Trees also support biodiversity by providing a suitable environment for insects, animals, and plants. 14. Agro forestry improve environment: Plants absorb CO2 and supply O2 in the process of photosynthesis, reduce pollutants from soil and water, reduce sound pollution, reduced pollution and make clean environments. 15. Agro forestry creates aesthetic value or ornamental value, protect humankind’s agricultural heritage 16. Agro forestry systems help in the reduction in incidences of total crop failure, which is common in monoculture and single cropping systems. Carbon Sequestration By trees Understanding the carbon cycle on our planet is crucial to combat our climate crisis. In our gardens, and on our farms, we can make choices that increase the rate of carbon sequestration over land. By increasing carbon sequestration in plants and soil, we can work to regain balance in our planet's carbon cycle. Carbon-conscious gardening and carbon farming are crucial tools in climate change mitigation. Carbon is present in the atmosphere, in the ground, in oceans and in living organic materials. It is exchanged between these different reservoirs through a wide range of natural processes. Without human interference, the natural flow of carbon would keep levels reasonably stable, and the carbon cycle would remain in harmonious balance. According to the Salk Institute, every year plants and other photosynthetic life capture 746 gigatons of CO2 and then release 727 gigatons of CO2 back. Unfortunately, human activity has dramatically increased the amounts of carbon (approximately 37 gigatons) that is released into the atmosphere annually. This imbalance in the carbon cycle is one of the main contributing factors to the greenhouse effect and global warming. We can help to redress the balance by: Choosing the right plants – to sequester as much carbon as possible, for as long as possible. Caring for the soil to boost its carbon capture capability. Protecting and restoring existing carbon sink ecosystems around the globe Most people are aware that planting trees is a good thing in climate change mitigation efforts. Trees take carbon from the air through the process of photosynthesis and store it as lignin in their trunks, roots and branches. This means that trees are able to turn CO2, from the atmosphere, into a very stable form of elemental carbon. Determining how much carbon an individual tree can sequester each year, and over its lifetime, is a complex business. Carbon sequestration rates are influenced by the species of tree, its size and age, temperatures and many other environmental factors. Even the best figures are only estimations, and it is difficult to get accurate figures. These figures are always extremely variable and will be accurate only for the very specific area where they were taken. Generally speaking; however, all trees have an astonishing capacity to store carbon while in growth. Research has shown that all tree species absorb CO2 from planting to old age (200 years plus). However, they reach their peak in terms of carbon sequestration in their 'teenage' years (from 10-45 years after planting). SCOPE OF AGROFORESTRY There is tremendous scope for Agro forestry because more focused on the ecological problems and shortage of fuel, fodder and other outputs as well as unemployment. Agro forestry has vast scope in meeting this requirement through multipurpose tree species as: (I) Large area is available in the form of farm boundaries, bunds, waste lands where this system can be adopted (II) This system permits the growing suitable tree species in the field where most annual crops are growing well (III) By growing trees and crops on Agricultural or forest land, Resources are utilized efficiently (IV) System has potential generate employment. (V) Provides raw material for the cottage industries (VI) Helps in maintaining ecological balance (VII) Soil and water conservation, soil improvement. (VIII) Helps in meeting various needs of growing population (IX) Solve the problem of acute shortage of fodder, fuel and other products along with fruits, shade and protection PROBLEMS, CHALLENGES AND OPPORTUNITIES 1. Problems and challenges of agroforestry development in terai and mid-hills Given the diverse uses, the day-to-day farming issues are far more complex than in a straight forward forestry operation or monoculture farm. It is difficult to use farm machines in the confined space of agro-forests. Food crops may be damaged during the harvest of tree products. Trees might serve as hosts to diseases, insects, birds and small animals. Rapid regeneration of aggressive trees may displace food crops and take over entire fields. Agroforestry is more labor intensive than plantation of single crops. There is shortage of farm-workers because of migration of villagers to urban and foreign countries for better job opportunities and services. In most of the terai region, farmers are planted of trees only rather than agroforestry practices because of shortage of farm worker, shortage of water, lack of technical knowledge. Growing agriculture and forest crops needs the understanding of silviculture and management aspects of the trees and crops. The technical knowhow of the farmers are limited Farmers have poor knowledge on agroforestry systems and lack of appropriate nursery, seed of improved species, and appropriate management systems. So the concerned organization needs to disseminate information and technical understanding to the farmers for better returns from the field. Agriculture crops are the first priority of the farmers and they have fear of casting shade by the trees and hamper the growth of the crops. In such dilemmas, technical support from concerned authorities is being lacked. Good quality and vigor seedlings of forest and horticulture crops are not easily available. If they are available, it is difficult to assure of their quality. Farmers were concerned about the easy availability and certified seedlings of their interest. Species combination plays important role to enhance the production and protection capacity of the agroforestry farm. The study found that appropriate species combinations are mostly overlooked. Eg. the species that shade leaves during agricultural period and that flourish green leaves during the winter fodder deficit season when farmers are in need of fodder trees to feed their livestock. Many agroforestry practices especially tea, coffee, and cardamom based are shifting from subsistence to commercial based practices in western and eastern part of Nepal. In the same time, farmers were concerned about the marketing of these products. There is lack of two way market linkages and buy back guarantee of the agroforestry products which discourage the farmers to continue the practices in the long run. Value added tax imposed to the forestry crops have also discouraging and bringing frustration among the farmers. Return on investment from planting trees takes many years and it is long term investment with risk of failure from environmental, social and technical reasons. Risk of insect and pest infestation may destroy the trees and crops. Most of the farmers especially in mid hills have very small land holding size which limits the adoption of agroforestry practices to subsistence farming practice only. 2. Opportunities of Agroforestry development in terai and mid hills There are tremendous opportunities for agroforestry development and scaling up the system in mid- hills and terai region of Nepal. Agroforestry is more profitable than forestry alone, and may have several climatic and social advantages for the farmers as well as for the local and national prosperity. To create clean environment for promotion and to widen the opportunity of agroforestry in mid-hills and terai region of the country. It has a tremendous opportunity to integrate agricultural, forest and horticultural crop in other wooded land. / Proper utilization of fallow farmlands and marginal lands. So, so it has a great opportunity to extend the commercial and systematic agroforestry in those lands contributing to the income and livelihood of millions of people together with an opportunity of employment and minimized the migration. Every year, many terai and hill farms are converted into degraded land due to natural hazards such as landslides, erosion, flooding, river course change, etc. In such land area, agroforestry can be developed as rehabilitation measures and greening the hills and plains and can be means of rural development as trees and crops can be managed simultaneously and guarantee the sustainability of the system along with its contribution in household livelihoods. Agroforestry is a biodiversity-friendly land-use system that plays a strategy for wildlife corridors and connectivity development. Agroforestry crops help in carbon sequestration and provide multiple benefits to the farmers. Thus, it has a great potential to contribute to climate change mitigation and manage ecosystem. Needs of Agro forestry System The different aspects in which agro forestry hold viable potentials to meet the demands of ever- growing human and livestock population are as follows: i) Fulfill the demand of food, fuel wood & fodder Enhanced food production of crops associated with trees through nitrogen fixation, better access to soil nutrients due to high cation-exchange capacity of the soil and its organic matter and mycorrhizal associations Fulfill the needs of food for man from trees as fruits, nuts and cereal substitutes Good source of Fodder for animals and good shelter of birds. ii) Water conservation Improvement of soil-moisture retention in rain fed croplands and pastures. Reducing flood hazards and a more even supply of water through reduction of run-off. Improvement in drainage from waterlogged or saline soils by trees with high water requirements. iii) Fuel wood and energy Provide Fuel-wood for cooking and direct combustion Pyrolytic conversion products such as charcoal. oil and gas Extraction of Oils, latex and other combustible saps and resins iv) Shelter from trees It provides the Building materials for shelter, construction and furniture's Shade trees for people, livestock and shade-loving crops Wind-breaks and shelter-belts for protection of settlements, crop lands, pastures and roadways Fencing: live fences and fence posts v) Raw material for industries Provides Raw material for pulp and paper industry Tannins, essential oils and medicinal ingredients Wood for agricultural implements and various crafts Fibre for weaving vi) Cash benefits Direct cash benefits from sale of tree products More income per unit of land than monoculture vii) Increased yield and maximized production: Combining agriculture crops with trees helps in increasing the productivity of the land by: Many leguminous tree species fix nitrogen from the atmosphere and return much more in leaf fall than they take from soil. Leaves of tree species could be used as green manure and help the farmer to increase soil productivity at optimum levels over a long period of time. viii) Diversified products: Several trees, shrubs, herbs and climbers yield a substantial quantity of food materials which are used by rural poor and particularly by tribal. About 213 species of large and small trees, 17 species of palm, 128 species of shrubs, 116 species of herbs, 4 species of fern and 15 species of fungi are known to yield edible/food material. Thus, by adopting agro forestry one can get diversified products viz. fuel, fodder, fruits, fibre, timber, etc. Tree and agriculture crop production system is more productive and is capable of meeting almost all the demands of timber, fodder, fruits, fiber and firewood. ix) Utilization of wasteland and degraded land: West and degraded lands are utilized properly by the cultivation of trees. x) Employment opportunities: Agro forestry systems increase the employment opportunities. Wood based industries such as saw milling, furniture, sports goods, pulp and paper; Match splints, bamboo and cane furniture, etc. are the important sectors where rural youth get employment. xi) Carbon sequestration services and its influence on climate change: One of the most important contributions of agro forestry in general is to respond to climate change through sequestration of carbon in above ground plant biomass and below ground biomass in the soils. xii) Potential reduction in the rate of deforestation: Agro forestry reduced the annual rate of deforestation to a great extent. The time that household/family members especially women would have spent walking long distances in search of fuel wood in forests can be saved. xiii) Improved soil health Trees improve physico-chemical properties of soil. The trees biomass also provide favorable environment for soil microbes and fauna which in turn break down the biomass and release plant nutrients. xiv) Agro forestry as a habitat for wild species Agro forestry can enhance connectivity and landscape heterogeneity in multi-functional conservation landscape. Assignments: 1. Define agro forestry it's important, scope and limitation of agro forestry in Nepal, suggest how can improve limitation. LECT- 3 & 4: TREE SELECTION AND IMPROVEMENTS SELECTION OF TREE CROP SPECIES FOR AGROFRESTRY Agro forestry is a deliberate integration of trees and crops in general, in same unit of land. These trees and crops compete with each other for nutrients, moisture and light. Among different components one must select a compatible component so that from a single unit of land a farmer/cultivator maximize his production. While selecting tree species for agro forestry there are three factors must taken into consideration. 1. CLIMATE 2. SOIL 3. BIOTIC FACTOR 1. CLIMATE:- The forest of Nepal has been described here on the basis of the levels of altitude, and different types of climate under the following vegetation zones: 1. Tropical zone(-1,000m): This zone principally includes Terai, Bhabar, and Dun valleys. It extends from east to west up to 1,000m and major vegetation types are Sal forest, Tropical deciduous riverine forest and Tropical evergreen forest. The common tree associates are Terminalia belliraca, T. chebula, Dillenia pentagyna, Butea monosperma, Mimosarubbicaulis, M. pudica. 2. Subtropical zone (1,000-2,000m): This zone prevails to an elevation of 1,000-2,000m. It comprises the outer foothills, lower parts of Mahabharat range, midland areas and Himalayas. Schima- Castanopsis, Pinus roxburghii and Alnus nepalensis are the important forest types. The associated tree species are Engelhardia spicata, Acer oblungum, Michelia kisopa, Persea odoratissimia, Litsea doshia, Ficus nerrifolius, F. auriculate, etc. 3. Temperate zone (2,000-3,000m): It runs almost parallel and north to outer foothills from east to west and includes mainly the Mahabharat range and the southern sides of the main Himalayan ranges. The region falls at an altitude of 2,000-3,000 m and is characterized by lower temperate mixed broad-leaved forest, temperate mixed evergreen forest, and upper temperate mixed broad-leaved forest. The forest is evergreen majorly composed of laurels such as Persia duthiei, P. odoratissima, P. pallida, Neolitsea pallens, Quercus lamellose, Q. glauca, Q. semecarpifolia etc. etc. 4. Subalpine zone (3,000-4,100m): It covers the part of the greater Himalayas between 3,000-4,100m. It is characterized by Silver fir and Birch-Rhododendron forests. In the west region, the birch occurs mixed with fir and oak. In the inner valleys it occurs with Juniperus recurve, Prunus cornuta, and shrubs, climbers and herbs are Lonicera myrtillus, Cortoneaster acuminatus, Campanula latifolia, Inula roylena, Rhodiola himalensis etc. 5. Alpine zone (4,100-5,500m): This zone above 4,100m comprises the association of Juniper-Rhododendron-Caragana- Lonicera, and alpine meadows. In the heads of Inner valleys between 4,000-4,300m, Juniper-Rhododendron association includes Juniperus spp (J. recurva, J. indica, J. indica) and Rhododendron spp. (R. anthopogon, R. lepidotum) on exposed slopes. The other associated species are Lonicera myrtillus, L. obovata, Ephedra gerardiana, Spiraea arcuate, etc. Some of the striking and ornamental plants in this belt are Anemone obtusiloba, Campanula aristate, Corydalis meifolia, C. ramosa, Delphinium brunonianum, D. vestitum, Gentiana depressa, G. prolata, G. venusta, Maharanga emodi, Mecanopsis dhwojii, M. horridula, M. simplicifolia, Primula calderana, P. sikkimensis, P. tibetica etc. 2. SOIL:- TREE SPECIES SELECTED FOR AGROFORESTRY TAKING INTO ACCOUNT SOIL TYPE Desert soil: Prosopis cineraria, P. chilensis, Acacia tortilis, A. senegal, A. nilotica, Salvadora spp Recent alluvium: Acacia catechu, Dalbergia sissoo, Bombax ceiba etc. Old alluvium: Saline-alkali soils: Prosopis spp, Acacia nilotica, Azadirachta indica, Ailanthus spp, Eucalyptus spp, Tamarix spp, Pongamia pinnata Coastal and deltaic alluvium: Casuarina equisetifolia, Cocus nucifera, Areca catechu, Avicennia spp Red soils: Tectona grandis, Madhuca indica, Mangifera indica, Dalbergia sissoo, Acacia nilotica, Leucaena leucocephala, Azadirachta indica, Eucalyptus hybrid, Pterocarpus marsupium, Adina cardifolia, Dendrocalamus strictus Black cotton soils: Acacia nilotica, A leucophloea, Tectona grandis, Hardwickia binnata, Adina cardifolia, Tamarandius indica, Aegle marmelos, Bauhinia spp, Dalbergia latifolia Laterite and lateric soils: Tectona grndis, Eucalyptus spp, Acacia auriculiformis, Azadirachta indica, Tamarindus indica, Emblica officinalis Peaty and organic soil: Syzygium cuminii, Ficus glomerata, Bischofia javanica, Lagerstromia speciosa, Glircidia sepium Hill soils: Juglans regia, Alnus nitida, Toona serrata, Cedrus deodra, Quercus spp, Grewia optiva, Celtis australis 3. BIOTIC FACTORS:- Choice of species is also governed by biotic factors such as grazing, fire and incidence of Insect pest etc. A. THE ROLE OF TREES IN LAND USE AND PEOPLES NEEDS 1. Trees for Products and services derived like food (arable crops, vegetables, honey, pollen, animal products, fruiuts, mushroom oils, nuts and leaves), shelter, energy, medicine, cash income, raw materials for crafts, fodder and forage and resources. 2. Trees for Food and nutrition eg. variety of fruits and other edible products 3. Trees for shelter and other structures eg. timber and poles 4. Trees for medicine eg. variety of species of trees and shrubs, as well as herbs, 5. Trees for cash, savings and investment Eg. Products sold for cash are fruits, timber and poles 6. Trees can help in conservation of soil and water, enhance soil fertility and improve soil structure. 7. Trees for livestock and beekeeping 8. Trees for maintained environment 9. Trees for latex (Rubber from Haveabrassilensis) , gum and resins , Fiber, pulp for paper, tannin, lac production 10. For Thatching and hedging materials, Gardening materials like stick, stacking materials, poles, fencing materials, handle of tools etc. 11. For Crafts product from Albizia, Somtalum, Tictona, Gmelinasp., Dallarmasjy. 12. Recreation agro-tourism, sport, hunting etc. 13. Ecological and socioeconomic services Important of trees 1) Trees are the main source of Oxygen. 2) An average tree produces enough oxygen to fulfill the oxygen need of four people. 3) Trees help in absorbing dust and other pollutants from the air, thus cleaning it. 4) The land under the tree absorbs more rainwater and helps prevent floods. 5) Trees also absorb a considerable amount of sound and help reducing noise pollution. 6) Birds lay their eggs in the nests on the tree, thus trees also help in nurturing many species. 7) Many trees also have medicinal properties and are used in healthcare industries. 8) They also save us from the harmful Ultra Violet rays, which is responsible for skin cancer. 9) Trees are also important for many industries, like Timber, Paper, Rubber, Silk etc., helping in economic development. 10) From roots to leaves, every part of a tree is beneficial to us. Common uses of Trees in an Agro forestry system 1. Trees in home garden, path, roadside, public places 2. Trees in crop land and pastures 3. Trees in alley cropping 4. Trees in contour line and water ways 5. Living fence, borderline planting and boundary planting 6. Trees for wind break and shelter belts 7. Trees on earth works or soil conservation 8. Woodlot production 9. Protein bank for livestock Potential Tree species for Agro forestry System 1. Timber tree species:– Teak (Tectonagrandis) –Poumoli (Flueggeaflexuosa) –Caribbean Pine (Pinuscaribaea–Mahogany (Swieteniamacrophylla)–Terminalia cattappa–Pandanusspp. 2. Trees that provide food, fruits & nuts Coconut (Cocusnucifera)-Breadfruit (Artocarpusaltiles)-Coffee ( Coffeaarabica)-Cocoa (Theobromacacao)-Ngalenut (Canariumindicum)-Mango (Mangiferaindica)-Avocado ( Persia americana)-Papaya (Caricapapaya)-Citrus spp.Supply andexchangeof improvedplantingmaterial 3. Tree species for essential oil: -Sandal wood (Santalumspp.)-Coconut (Cocusnucifera)- Dilo(Calophylluminophyllum)-Mokosoi (Canangaodorata)- Agar wood (Aquilariaspp.) Masala (Ecalaptus spc.) 4. Multipurpose Trees:- Gliricidiasepieum-Azadirachtaindica-MoringaOleifera-Morindacitrifolia Suitable Species for Firewood/Fuel wood/ Energy Plantation for different regions 1. Tropical dry region: Acacia catechu, Acacia modesta, Acacia nilotica, Acacia Senegal, Acacia tortilis, Anogeissus pendula, Albizia lebbek, Azadirachta indica, Cassia siamea, Cordia rothii, Dalbergia sissoo, Emblica officinalis, Eucalyptus camaldulensis, Erythrina superb, Gmelina arborea, Parkinsonia aculeate, Peltophorum ferrugineum, Pongamia pinnata, Prosopis cineraria, Prosopis juliflora, Tamarindus indica, Tamarix troupe, Tecomella undulate, Zizyphus maurtiana etc. 2. Tropical humid region: Adina cordifolia, Acacia auriculiformis, Acacia catechu, Acacia nilotica, Albizia procera, Azadirachta indica, Cassia siamea, Casuarina equisetifolia, Dalbergia sissoo, Dendrocalamus strictus, Ficus spp., Eucalyptus spp., Kydia calycina, Leucaena leucocephala, Madhuca indica, Melia azedarach, Morus alba, Salix tetrasperma, Syzygium cuminii, Tamarindus indica, Trewia nudiflora, Gliricidia sepium and Gmelina arborea. 3. Sub-tropical region: Acacia catechu, Acacia melanoxylon, Acacia nilotica, Aesculus indica, Ailanthus excels, Celtis australis, Grevillea robusta, Michelia champaca, Populus deltoids, Populus nigra, Robinia pseudoacacia, Salix alba and Toona ciliate. 4. Temperate climate: Acer spp., Aesculus indica, Alnus nepalensis, Alnus nitida, Celtis australis, Populus ciliate, Quercus semecarpifolia, Salix alba and Toona serrata DESIRABLE CHARACTERISTICS OF TREES FOR AGROFORESTRY SYSTEMS While selecting tree species for agro forestry systems, the following desirable characteristics should be taken into consideration. 1. Minimum interference with crops with respect to soil moisture, nutrients and sunlight. 2. Adequate shade regulation and upright stems. 3. Easy establishment and good survival rate. 4. Fast growing habit such as Poplar, Casuriana, Leucaena leucocephala etc. are important species which provide lot of opportunities to be planted in AFS and easy management. 5. Fixes atmospheric nitrogen. 6. High re-sprouting capacity after lopping, coppicing, pollarding and pruning. 7. Deep root system with very few lateral roots 8. No toxic effects on soil and on associated crop plants 9. Multiple products like fuel wood, leaf fodder, edible fruit, edible flower and fibre 10. Suitable for local climatic conditions 11. Acceptable to local farmers and wider adaptability 12. Easily palatable and digestible for livestock 13. Shelter conferring and soil stabilization attributes Eg. Poplars (Populus spp.), Willows (Salix spp.), Casurina equisetifolia, etc. have been extensively used in soil erosion control because of their extensive root system and ability to grow in water-logged soils. 14. Nutrient cycling and nitrogen fixation attributes 15. Easily decomposable leaves, small in size, decompose quickly and easily, and add a large quantity of organic matter and nutrients to the soil 16. Free from chemical exudations like allelo-chemicals affect the growth of under-ground crops. CHARACTERISTICS OF AGRICULTURAL CROPS FOR AGROFORESTRY a) Agricultural crops should be short duration and quick growing. b) They should be at least partially tolerant to shade. c) Most of them should belong to Leguminosae family. d) They should respond well to high density tree planting. e) They should bear some adverse conditions, like water stress and/or excess of watering; f) Crops should return adequate organic matter to soil through their fallen leaves, root system, stumps, etc. g) Crops should appropriately be fitted in intensive or multiple cropping system. Assignments: 1. Highlight the characteristics of trees which are used in agro forestry system. 2. Listing the trees at list five commonly uses for agro forestry system in Nepal with climatic zone, botanical name and family. Trees used in home garden, path, roadside, public places, soil conservation, fence, boundary, fodder, fruits vegetables, wine break, shelter/ construction, furniture, medicinal, ornamentals, fuel wood, erosion control, nitrogen fixing etc. LECT- 5 & 6 AGROFORESTRY SYSTEM (AFS) Classification of Agro forestry System According to. Nair (1987), agro forestry systems can be classified in to the following basis/sets of criteria: A. Structural basis: Considering the composition of the components, including spatial admixture of the woody component, vertical stratification of the component mix arid temporal arrangement of the different components. B. Functional basis: This is based on the major function or role of the different components of the system, mainly of the woody components (these can be product, e.g., production of food, fodder, fuel wood and so on or protective, e.g., windbreak, shelter-belts, soil conservation and so on). C. Socioeconomic basis: Considers the level of inputs of management (low input, high input) or intensity or scale of management and commercial goals (subsistence, commercial, intermediate). D. Ecological basis: Takes into account the environmental conditions on the assumption that certain types of systems can be more appropriate for certain ecological conditions. There may be a set of AF systems for arid and semi-arid lands etc. A. Structural Basis of Classification The structural of a system can be defined in terms of its components and the expected role or function of each. In this system the type of component and their arrangement are important. Hence, on the basis of structure, AF systems can be grouped into two categories: 1. Nature of components and 2. Arrangement of components. 1. Nature of Components : Based on the nature of components, AF systems can be classified into the following categories; a. Agrisilvicultural systems b. Silvopastoral systems c. Agrosilvopastoral systems and d. Other systems. a. Agrisilvicultural System (crops and trees + shrubs/vines and trees) This system involves the conscious and deliberate use of land for the concurrent production of agricultural crops including tree crops and forest crops. Based on the nature of the components this system can be grouped into various forms. 1) Improved fallow system When the fallow is enriched with fast-growing trees, shrubs or vines, the practice is called "improved fallow." Improved fallow is an agro forestry practice that has its origins in slash-and- burn agriculture. The trees and shrubs are left to occupy the site for several months or years. In this system, planting a crop is done in the fallow lands at the end of shifting cultivation. This practice decreases soil erosion in the subsequent years and recovers depleted soil nutrients. 2) The Taungya system The ‘Taungya’ is a Burrvege word consisting of ‘Taung’ means hill and ‘ya’ means cultivation i.e. cultivation in the hill. Taungya was reported to have started first in Burma in the year 1850 and in Java 1956. Taungya was introduced to India by Brandis in 1956. In Nepal, it was initiated in 1972 at Tamagadhi area of Bara District. This area was originally covered with Sal and Asna their associates. The forest area is highly encroached by the hill migrants. Therefore, the Taungya system was introduced to save these forests. Types of Taungya i) Departmental Taungya Agro crops are raised by the Department by employing labors and its main objective is to suppress the growth of the unwanted vegetation and enhances tree growth. ii) Leased Taungya The plantation area is given to the farmers, who offer the highest amount of money for a specified period of time. iii) Free Taungya Land is given to the farmers without charging money. iv) Village Taungya Of all the Taungya systems, it is the most successful system. People are allowed to settle as a village inside the forested areas and land is given an area of 1 ha for raising agro-crops for 3-4 years. Characteristics of Taungya ❖ Modified form of shifting cultivation. ❖ Crops are raised one year before the plantation. ❖ Crops and trees are raised simultaneously. ❖ Areas are abandoned after the canopy closes. ❖ Cycle is very short (3-4 years). ❖ After the completion of one cycle farmers have to move to another site if available. Advantages ❖ It is obtained cheaply which reduces the cost of planting and maintenance. ❖ It solves the problem of unemployment. ❖ It helps maximum utilization of the site. ❖ It offers high reneumerization to the forest department. ❖ It has a provision for food crops in addition to forest trees. ❖ Weed and climber growth are effectively eliminated. ❖ There will be the multiple value such as timber, fodder, fuel wood, etc. Problems/disadvantages Farmers may cut the trees for the favor of crop growth. More crops per unit may deplete the soil fertility. Exposure of soil enhances the soil erosion. There may be danger of epidemic diseases and spread from food crops to forest trees. Legal problems arise on the land allocation and returning. It is the form of human labor exploitation. 3) Multispecies tree garden In this system, mixture of various kinds of tree species are grown to provide multiple output such as food, fodder and wood products. 4) Trees and shrubs on pasture 5) Alley cropping/Hedge row intercropping (given in previous model chapter) 6) Multi-purpose tree and shrubs In this system, various multipurpose tree species are planted scatter or in some patterns. This system produces multiple products and offers productive function too. The suitable trees are Leucanaenaleucocephala, Acacia albida, Cassia sisamea, Casaurinaequisetifolia, Azadirachtaindica, Acacia Senegal, Cocusnucifera etc. 7) Crop combination with plantation crops In this, perennial trees and shrubs (coffee, tea, coconut) are combined in the intercropping systems 8) Agro forestry fuel-wood plantation In this system, fuel wood species are inter-planted on or around agricultural lands. This system acts both fence as well as shelter-belts besides proving fuel wood to local community. Suitable trees species for this system are Acacia nilotica, Albizzialebbek, Cassia siamea, Casaurinaequisetifolia, Dalbergiasissoo, Prosopisjuliflora, Eucalyptus terticornis etc. 9) Shelter belts Shelter-belts are the belt of rows of trees established at right angle to the prevailing wind direction. Shelter-belt deflects the air currents and thus by reduces the wind velocity and erosion. It provides protection to the leeward areas against wind erosion and decreases the desiccation effects on plants. It also provides food, fodder and timber. Shelter-belts have a typical pyramidal shape. This is achieved by raising tall trees (a) in center and medium sized (b) trees in adjacent to both side. Thereafter, shrubs (c) and grasses (d) are planted in a similar fashion. Shelter-belt up to 50 meter width with suitable spacing is ideal. The ratio of the height and width of shelter-belt should be roughly 1:10. Shelter-belts are oriented right angled to the prevailing wind direction. Shelter-belts are raised in quadrangles (4 sided spatial) if the wind direction to change very often. The minimum length of protection given by a shelter-belt is about 25 times its height. The following species are recommended for shelter-belt establishment: ✓ Grasses: Saccharumspontanizem, S. munja, Panicumantidotale, Ceuchrus sp. Etc. ✓ Shrubs: Calotropisprocora, Clerodendronphlomoides, Cassia auriculata, Dodonaia viscose etc. ✓ Tree species: Acacia Arabica, A. leucopholea, Dalbergiasissoo, Eucalyptus spp. Tamarix articulate, Parkinsonia aculeate, Prosopsisjuliflora, Casaurinaequisetifolia etc. 10) Wind breaks Wind breaks refers to the strip of trees and/ or shrubs planted in order to protect fields, homes, canals or other areas from wind and blowing soil. It protects the livestock from cold winds. Windbreak protects crops and pastures form hot and drying winds. Windbreak reduces soil erosion and provides habitat for wildlife. It reduces the evaporation from farmlands and improves the micro-climate. It acts as a fence and boundary, it retards grass fire during summer season. In addition, wind break provides useful products such as poles, fuel wood. Fruit, fodder, fiber and mulch. Usually, in general, trees with narrow, vertical growth are ideal for wind break which includes Eucalyptus, Cassia, Propis, Leucaena, Casaurina, Acacia, Grivillea, Syzygium and Dalbergia species. 11) Soil conservation hedge In this system, trees can be planted on soil conservation works such as bund and terraces. These trees augment the conservation work through stabilization of soil. The interception of rain and obstruction of wind reduces the soil erosion. Grevillearobusta, Acacia catechu, Pinusroxborghii, Prosopoisjuliflora, Alnusnepalensis, Leucaenaleucocephala are used for this purpose ewith grasses. 12) Riparian Buffer A riparian buffer or stream buffer is a vegetated area near a stream, usually forested, which helps shade and partially protect the stream from the impact of adjacent land uses. It plays a key role in increasing water quality in associated streams, rivers, and lakes, thus providing environmental benefits. b. Agrosilvopastoral system (trees + crops+pasture/animals) This system refers to the production of woody perennial along with annuals and pastures. This system is grouped into two categories viz. home garden and woody hedge rows for browse, mulch, green mulch and soil conservation. I. Home Garden This is one of the oldest agro forestry practices, found extensively in high rainfall areas in tropical south and south-east Asia. Many species of trees, bushes, vegetables and other herbaceous plants are grown in dense and apparently random arrangements, although some rational control over choice plants and their spatial and temporal arrangement may be exercised. Most home gardens also support a variety of animals (cow, buffalo, bullock, goat, sheep) and birds (chicken, duck). In some places pigs are also raised. Fodder and legumes are widely grown to meet the daily fodder requirements of cattle. The waste materials from crops and homes are used as fodder/feed for animals/birds and barn wastes are used as manure for crops. Homestead occupies an area around 0.2-0.5 ha. This system is managed by family members. Home garden is also called as Multi-tier system or Multi-tier cropping as it consists of different canopy strata. In this system, herbaceous plant constitutes the ground layer and trees occupy the top storey. In the ground layer, vegetables grwon up to lm height whereas food crops such as banana, papaya occupies layer of 1-3 m. The woody species occupies the top layer which includes Atrocarpusheterophyllus, Citrus spp., Psidiumguajava, Mangiferaindica, Azadirachtaindica, Cocusnucifera etc. II. Woody Hedge rows In this system various woody hedges especially fast-growing and coppicing fodder shrubs and trees, are planted for the purpose of browse, mulch, green manure, soil conservation etc. The main aim of this system is production of food/fodder/fuel wood and soil conservation. The suitable species for this system are: Erythrium spp., Leucaenaleucocephala&Sesbaniagrandiflora etc. c. Silvopastoral systems Silvipasture refers to the production of woody plants in pasture land, the trees and shrubs mainly provide fodder. The majority of rangeland grazing in hills is typically comprise the grazing of natural herbaceous and shrubby vegetation for under trees such as pines, bhimal, Oak etc. This system is again classified into three categories:. The three categories of this system are as follows: I.Live fence of fodder trees and hedges In this system, fodder trees and hedges are planted along the boundaries which serve as a live fence in addition to providing fodder. The suitable species for this purpose are: Gliricidiasepizum, Sesbaniagrandiflora, Erythrina spp. & Acacia spp. II.Protein bank In this system, protein rich fodder trees are planted in and around range and farrow lands so as to augments the fodder quality and quantity in range lands. The suitable species are: Acacia nilotica, Albizzialebbek, Azadirachtaindica, Leucaenaleucocephala, Gliricidiasepim, Sesbaniagrandiflora etc. III.Trees and shrubs on pastures In this system, various trees and shrubs are scattered irregularly or arranged systematically which supplements forage production. Acacia nilotica, Tamarindusindica, Azadirachtaindica etc. are used for this purpose. d. Other Systems The following systems can be included: I. Apiculture with Trees: In this system various honey (nectar) producing tree species frequently visited by honeybees are planted on the boundary, mixed with an agricultural crop. The main purpose of this system is the production of honey. II. Aquaforestry: In this system various trees and shrubs preferred by fish are planted on the boundary and around fish-ponds. Tree leaves are used as forage for fish. The main or primary role of this system is fish production and bund stabilization around fish-ponds. III. Multipurpose Wood Lots: In this system special location-specific MPTS are grown mixed or separately planted for various purposes such as wood, fodder, soil protection, soil reclamation etc. 2. Arrangement of Components AF Systems The arrangement of components gives first priority to the plants even in AF systems involving animals. Their management according to a definite plan, say a rotational grazing scheme, gives precedence to the plants over the animals. Such plant arrangements in multispecies combinations involve the dimensions of space and time. I. Spatial Arrangement - Spatial arrangements of plants in an AF mixture may result in dense mixed stands (as in home gardens) or in sparse mix stands (as in most systems of trees in pastures). The species (or species mixtures) may be laid out in zones or strips of varying widths. There may be several forms of such zones, varying from microzonal arrangements (such as alternate rows) to macrozonal ones. II. Temporal Arrangement - Temporal arrangements of plants in AF may also take various forms. An extreme example is the conventional shifting cultivation cycles involving 2-4 years of cropping and more than 15 years of fallow cycle, when a selected woody species or mixtures of species may be planted. Similarly, some silvopastoral systems may involve grass leys in rotation with some species of grass remaining on the land for several years. These temporal arrangements of components in AF are termed coincident, concomitant, overlapping (relay cropping), separate and interpolated. Crop combinations with plantation crops: Perennial trees and shrubs such as coffee, tea, coconut and cocoa are combined into intercropping systems in numerous ways, including: i. Integrated multistory mixture of plantation crops;.immixture of plantation crops in alternate or other crop arrangement; iii.Shade trees for plantation cropsiv.Intercropping with agricultural crops. Tea (Camilia sinensis) is grown under shade of A. chinensis,A. odoratissim,A. lebbek,A. procera, Acacia lenticularis,Derris robusta,Grevillea robusta, Acacia spp., Erythrina lithosperma, Indigofera tesmanii. a) Coffee (Coffea arabica) is grown under the shade of Erythrina lithosperma as temporary shade while, permanent shade trees include Ficus glomerata, F. nervosa, Albizia chinensis, A. lebbek, A moluccana, A. sumatrana, Dalbergia latifolia, Artocarpus integrifolius, Bischofia javanica, Grevillea robusta. b) Cacao (Theobroma cacao) is grown under the shade of coconut and areca nut,and Dipterocarpus macrocarpa (in forest). c) Black pepper (Piper nigrum) is grown with support from Erithrina indica, Garuga pinnata, Spondias, Mangifera, Gliricidia maculate and Grevillea robusta. d) Small cardamom (Elettaria cardamomum) and large cardamom (Ammomum subulatum; A. aromaticum) grow in forests under temporary shade tree of Mesopsis emini.. e) Large cardamom is grown under the shade of natural forest as well under planted shade treesviz., Alnus nepalensis, Schima wallichii; Cinchona spp.; Lagerstroemia spp., Albizia lebbek; Castanopsis tribuloides; C. hystrix; C. indica; Terminalia myriocarpa; Bischofiajavanica. Suitability of agro forestry system: Condition/Area Agro forestry System i. Humid tropical/ Subtropical Home garden, Trees on rangelands and pastures, Improved fallow in lands shifting cultivation, Multipurpose woodlots. ii. Semi-arid/arid lands Silvipastural system iii.Tropical high lands Woody perennials for soil conservation, Improved fallow. B. Functional basis Classification of Agro forestry Systems Two fundamental attributes of all AF systems are productivity and sustainability. This clearly indicates that AF systems have two functions. Functions of agro forestry 1. Productive: Agro forestry can produce food crops, fruits, leaf litter, timber, fuel wood and fodder for livestock from the same piece of land. 2. Protective: Agro forestry helps to minimize degradation of farmland and other natural resources (e.g., wind break, shelter-belt, soil and moisture conservation and soil erosion). 3. Ameliorative: Agro forestry with legume trees and crops help to maintain or improve the productivity of land. 4. Livelihood improvement: Income can be generated from sale of trees and agricultural products. C. Socioeconomic basis Classification of Agro forestry Systems Based on such socioeconomic criteria as scale of production and level of technology input and management, agro forestry systems have been grouped into three categories: 1. Commercial, 2. Intermediate and 3. Subsistence systems D. Ecological Grouping of Agro forestry Systems Based on the major agro ecological zones, agro forestry systems are grouped into the following categories: I. Humid/sub-humid lowlands: This region is characterized by hot humid climate for all or most of the year and evergreen or semi- evergreen vegetation. The lowland humid and subhumid tropics (commonly referred to as the humid tropics) are by far the most important ecological region in terms of the total human population. It supports extent of area and diversity of agro forestry and other land-use systems. Because of climatic conditions that favour rapid growth of a large number of plant species, various types of agro forestry plant associations can be found in areas with a high human population, e.g., various forms of home gardens, Plantation of crops with combinations and multilayer tree gardens, in areas of low population density, trees on rangelands and pastures. II. Semi-arid/arid lands: This region is characterized by rainfalls confined to 9-21 days in July -Sept., 2-4 wet months, vapour pressure deficit ranging from 9 mb in January to 30 mb in April May, solar radiation incidence (400- 500 cal/cm2/day), high wind velocity (20 km/hour), high potential evapotranspiration (6 mm/day) and high mean aridity Index (70-74.8%). III. Highlands: Variable rainfall, degraded and shallow lands at high altitude to deep rich soils in valleys and great climatic variations are the features of highlands. This area is a storehouse of great biological diversity. The Himalayan region is an excellent example of this type of area. Agro forestry has long encompassed many well-known land-use systems practices. Important Land use systems in Nepal / Different types of Agroforestrv models 1. Alley cropping/Hedge-row intercropping: It is one of the promising models of agro forestry where arable crops are grown in the alleys between the rows of woody perennials (AFS) and the trees are pruned periodically during the peak growing season of the crop to prevent shading and to provide green manure or mulch to arable crops. Currently a large number of organizations are involved in arraying out research activities on alley cropping. IITA , Ibadan, Nigeria (1972) is the pioneering organization to evolve and popularize the concept of alley cropping all over the world. 2. Boundary Planting: It is one of the conventional agro forestry system where the trees are planted on the farm boundaries to demarcate the boundaries.\ 3. Strip Hedge-row Intercropping: In this model strips of tree rows are altered with agro-crops. 4. Concentric Design: In this model tress are sparsely planted on the ground and agro-crops are planted around the periphery in a circular fashion. This design offers the advantages of studying the effect of orientation (North, South, East& West) on productivity. 5. Contour Hedge rows intercropping: In this model trees are planted on contour at a close spacing of 1 -2 m and pruned branches are left on the contour lines which provides a barrier to the flow of run-off. This model progressively transforms sloping area into terraces. 6. Nelder-Wheel model: This model was developed by an American forester. It is one of the efficient models to study tree- crop interaction effects over a wide range of spacing. Special features of this model are as follows: a. Spacing for trees is fixed on each spoke b. Tree rows radiates towards outside from the hub c. Even on a small area; growth of the trees can be assessed and compared between and among the species over the wide range of spacing d. It is the most effective and demonstrative block design to date to experiment on singular and multiple species e. Spacing to the nearest neighbour progressively varies f. Data could be regenerated for regression modeling g. Spacing x Spacing interaction could be studied h. Shape of the area available for each species is constant but the size increases radially. i. Areas having irregular shapes too can be utilized for carrying out experiments j. j. Aesthetically the model is appealing Limitations: a) Requires some degree of skills in laying out grounds b) Little implication on slopes Over View of AFS in Nepal and Similar Agro-eco Zoning in the World: The country can be divided into five physiographic zones based on altitude: Terai, Siwalik, Middle Mountain, High Mountain and High Himal. Terai is a fl at and plain land inclining gently towards south of Nepal with average elevation from 70 to 300 meters. On its north lies Siwalik, the elevation between 300 m to 920 m. The Middle Mountains are located at an altitude between 200 m and 30001 m between the Terai and the High Mountains. The High Mountain and High Himal fall in the northernmost part of the country on the border with China. The altitude in these regions is typically more than 2300 m. Climatically, the country can be divided into three distinct seasons. Cold season from October to February, Hot and dry season from March to mid-June and Rainy season from Mid-June to the end of September. The average annual rainfall in Nepal is about 1,600 mm. The eastern region is wetter than the western region due to early and higher rainfall. Eighty percent of precipitation comes in the form of the summer monsoon rain prevailing in the country from June to September. Winter rains are more common in the western hills. Temperature varies with topographic variations in the country. In the Terai, winter temperature is between 22° -27° C while summer temperature exceeds 37°C. In the mid-hills, temperature is between 12° – 16° C and in higher up occasionally it snows. Nepal has a population of 26.5 million with the population density of 180 people per square kilometer. Approximately 70% of the people are forest dependent and 66% of the population live off a combination of agriculture and forest products. The economic growth of the country in terms of Gross Domestic Product (GDP) was 3.5 % in the year 2010/2011. Agriculture and Forestry are estimated to contribute about 33% of the GDP followed by non-agriculture sector such as industry, housing rent, and the real market (67%). The Human Development Index is 0.55According to the new constitution of Nepal (2072), the country is divided into seven (7) Pradesh (provinces). Table : Number of districts in each Pradesh (province) and forests area coverage. Provi # Districts Name Total land Forest Forest Total % nce # Districts area (ha) area (ha) area (%) forest 1 14 Taplejung, Panchthar, Illam, 25,90,500 11,34,250 43.78 17.3 Sakhuwa sabha, Tehrathum, Dhankuta, Bhojpur, Khotang, Solukhumbu, Okhaldhunga, Udayapur, Jhapa, Morong and Sunsari 2 8 Saptari, Siraha, Dhanusha, 9,66,100 2,63,630 27.29 4.4 Mahottari, Sarlahi, Rautahat, Bara and Parsa 3 13 Dolakha, Ramechap, Sindhuli, 20,30,000 10,90,877 53.74 17.5 Kavrepalanchok, Sindhupalchok, Rasuwa, Nuwakot, Dhadhing, Chitawan, Makawanpur, Bhaktapur, Lalitpur and Kathmandu 4 11 Gorkha, Lamjung, Tanahun, 21,50,400 7,96,991 37.06 11.7 Kaski, Manag, Mustang, Parbat, Syanja, Myagdi, Baglung and Nawalparasi (Barda ghat East of Susta) 5 12 Nawalparasi (Bardaghat West of 22,28,800 9,87,445 44.30 15.9 Susta), Rupandehi, Kapilbastu, Palpa, Arghakhanchi, Gulmi, Rukum (East side), Rolpa, Piyuthan, Dang, Banke and Bardiya 6 10 Rukum (West side). Salyan, 27,98,400 11,90,631 42.55 16.1 Dolpa, Jumla, Mugu, Humla, Kalikot, Jajarkot, Dailekh and Surkhet. 7 9 Bajura, Bajhang, Doti, Acham, 19,53,900 11,46,106 58.66 16.9 Darchula, Baitadi, Dadeldhura, Kanchanpur and Kailali. Total 77 1,47,18,10 66,09,930 44.91 100 0 Source: Forest Research and Survey Department, 2016 MAJOR AGROFORESTRY SYSTEMS IN SOUTH ASIA The objectives of practicing agro forestry in all the countries of South Asia are the same i.e meeting household fuel wood requirement, fodder for livestock, grazing, conserving soil and water utilizing traditional agro forestry knowledge and technologies, learnt from their forefathers. However, depending on the countries, some of the practices is very diverse and tends to be complex. Integration of crop production, grazing animals and forest areas into a mutually supportive system is the main features of agro forestry being practiced in Bhutan. Ruminant (yaks and sheep) plays a critical role by providing draught power, manure and livestock products for sale or home consumption in this country. Planting trees on homestead and along the vicinity of farmland boundaries is common in Bangladesh. Agro forestry in India is more developed in comparison to other South Asian countries. India has already promulgated Agro forestry policy in the country. Both farm and forest-based Agro forestry systems are being practiced but the intensity and use differs along with the argo-ecological zones of the country. Silvo-pastoral practices are being practiced within village grazing grounds where villagers have their tenure rights whereas this system in forests involve lopping trees and grazing understory ground grasses. In Maldives, trees and shrubs species Griricidia (Gliricidia), Sesbania (Sesbania), Erythrina variegata are being used in agro forestry practices as fodder for livestock and to serve as wind breaks. Coconuts are extensively planted in and around homestead. Farmers are practicing trees as intercrops in uniform grid pattern as it provides fl exibility in arranging the spacing between the trees and individual farmer can remove them when they feel it necessary. In Sri-Lanka, agro forestry is one of the main sources of timber and food for the country. Two types of home garden systems prevail in Sri-Lanka; traditional and modern. In the traditional system, Jackfruit (Artocarpus integra) constitutes as an important component of most Sri-Lankan home gardens for house hold consumption whereas modern home gardens look at more cash generation through planting tree species that yield spices, beverages and sap. Sri-Lankan home gardens are considered the most complex and diverse in the world. The agro forestry systems commonly practiced in different regions of Nepal are as follows: Terai 1. Home gardens 2. Planting trees among agricultural crops 3. Intercropping with horticultural crops 4. Taungya 5. Silvofisheary 6. Apisilvocultural system 7. Silvopastoral system 8. Hortosilvopastoral system Siwalik Hills: 1. Silvopastoral system 2. Taungya system 3. Silvofisheary Middle Hills: 1. Alley cropping 2. Home garden 3. Hortosilvopastoral system 4. Contour hedge row system. Higher Hills 1. Silvopastoral system 2. Contour hedgerow system Agro forestry system and practices in Terai region are: S.N Agro forestry systems Agro forestry practices 1 Agrisilviculture Camelia sinensis (Tea) under Albizia procera and Dalbergia sissoo, Turmeric and ginger under Eucalyptus camaldulensis, Seasonal agricultural crops under Tactona grandis Seasonal agricultural crops along with mixed tree species 2 Hortisilviculture Banana along with Eucalyptus camaldulensis and Tectona grandis Mango along with Eucalyptus camaldulensis and Tectona grandis Avocado and pomegranate along with tree species Eucalyptus camaldulensis and Mangifera indica along with asparagus, citronella, palmarosa and mentha 3 Hortiagriculture Fruit trees along with seasonal agricultural crops 4 Agrisilvihorticulture Agricultural crops along with banana and tree species Fruit trees and agricultural crops along with Tectona grandis, Shorea borneensis and Dalbergia sissoo. Fruit trees, agricultural crops and seasonal vegetables along with eucalyptus Mango and agriculture crops along with Eucalyptus camaldulensis, Tectona grandis, Poplus species, Melia azedarach 5 Agrosilvipastoral Agricultural crops along with Acacia catechu, Elaeocarpus ganitrusa and pig farming. Agricultural crops, tree species along with grasses and livestock 6 Silvofishery Fish farming in conjunction with Eucalyptus camaldulensis, Tectona grandis , Mango and Dalbergia sissoo Fish farming along Tectona grandis, Paulownia tomentosa, and Shorea borneensis 7 Agrosilvifishery Fish along with Eucalyptus camaldulensis, Tectona grandis and seasonal crops. 8 Apiculuture Bee farming in conjunction with Tectona grandis and Paulownia 9 Agrohortosilvopastoral Agricultural crops and Areca catechu along with Tectona grandis, Eucalyptus camaldulensis, Elaeocarpus sphaericus, Shorea borneensis, Acacia catechu, and livestock 3. Agro forestry system and practices in Mid hill region are: S.N Agro forestry systems Agro forestry practices 1 Agrisilviculture Tea under Alnus nepalensis Cardamom under Alnus nepalensis Cardamom along with Thysanolaena maxima, Elaeocarpus ganitrus, Alnus nepalensis, Schima wallichi and fodder tree species. Cardamom and Coffee under Alnus nepalensis Coffee under multipurpose tree species Coffee, maize and seasonal vegetables under Elaeocarpus ganitrus Cinnamomum tamala along with agricultural crops Thysanolaena maxima along with Cinnamomum tamala Kiwi, cardamom and Chiraito along with Taxus wallichiana, Elaeocarpus sphaericus, Michlia champaca NTFPs along with agricultural crops and tree species 2 Hortosilvipastoral Swertia chiraita, Zanthoxylum armatum along with fodder and fruit trees Multipurpose trees, fodder trees, fruit trees, grasses along with livestock 3 Hortiagriculture Mango and Banana along with Maize Pear along with maize and seasonal vegetables Seasonal crops and vegetables under orange and sweet orange Coffee under Orange, Banana, Walnut and Jackfruit Zanthoxylum armatum along with orange and agriculture crops 4 Home garden Seasonal vegetables, fruit trees along with multipurpose trees 5 Silvopastoral Santalum album, Ziziphus budhensis, Schima wallichiana, Litsea monopetala, Ficus semicordata, Toona ciliata and grasses along with goat farming 6 Agrosilvihorticulture NTFPs along with fodder and fruit trees 7 Agrosilvipastoral Thysanolaena maxima along with fodder trees and livestocks Cardamom and Cinamomun Tamala along with Elaeocarpus ganitrus and Banana Scenario of AFS in Similar other Agro-eco Zoning in the World: Globally it has been acknowledged by FAO that about 30 to 33 % of the total geographical area must be under good forest cover to maintain a harmony among the various components of nature. Disastrous results of deforestation have already cast their shadows in many Asian countries. In future, repercussions could be still more annihilating and horrible. Therefore, it would be quite unwise to turn blind eyes to what had happened in Ethiopia. In many Asian countries, efforts are in progress to rehabilitate and reclaim the degraded forests. Further, large scale plantation program have been initiated under agro forestry and social forestry programs in areas outside the natural forests. However, there have been little achievements in many underdeveloped and developing Asian countries. There has been substantial reduction in Asia’s forest cover over the last thirty years. Although, about 30% of the land mass of tropical Asia and Pacific is forested, this varies widely by country from almost 80% Papua New Guinea to only 2% in Pakistan. There have been several reasons for deforestation resulting from a complex interaction of social, economic and edaphic factors. However, economic and environmental repercussions of declining forest reserves are much more apparent. Generally in Asia, experience has shown that negative economic effects become critical when forest cover decreases below 0.2 ha/capita. Table 4: Forested land area and per capita forested area in selected tropical Asian countries (1990) Country % of total land area Per capita forest(ha/capita) Pakistan 2.4 - Bangladesh 5.9 - India 17.4 0.1 Thailand 24.9 0.2 Vietnam 25.5 0.1 Philippines 26.3 0.1 Sri Lanka 27.0 0.1 Nepal 36.7 0.3 Myanmar 43.9 0.7 Malaysia 53.5 1.0 Indonesia 60.5 0.6 Cambodia 68.9 1.5 Papua New Guinea 79.5 9.0 Assignment: 1. What is Taungya system ? Give its advantages and disadvantages. 2. Differentiate between boundary planting and wind breaks in an agro forestry systems 3. Classify the Agro-forestry on the basis of arrangement of components. 4. Give an appropriate Agro-forestry system for Mid hills of Nepal Support your answers with diagram. 5. What is Neldes wheel model? Describe in brief. 6. Differentiate between a) Contour hedgerow intercropping and alley cropping, b) Iimproved fallow and bush fallow c) Boundary planting and wind breaks d) Riparian boundary and strip hedge row Lect- 7 & 8 TREE CROP INTERACTIONS/INTERFACE Introduction: Tree-crop interactions Interaction is defined as the effect of one component of a system on the performance of another component and/or the overall system (Nair, 1993). Regarding this, ICRAF researchers have developed an equation for quantifying tree crop interaction (I), considering positive effects of tree and crop yield through soil fertility enrichment (F) and negative effects through crop competition (C) for growth resources between tree and crop I=F-C. If F> C, interaction is positive, if F< C interaction is negative and if F=C interaction is neutral. Interaction occurs both above and below ground and includes a complex set of interaction relating to radiation exchange, the water balance, nutrient budget and cycling, shelter and other microclimatic modifications. There are a several complementary effects of tree crop interaction such as increased productivity, improved soil fertility, efficient and balanced nutrient cycling, improved Soil conservation management and improvement of Microclimate which are very important in the way of overall agro forestry health and its Interactions help to know How the components of agro forestry utilize and share the resources of the environment, and How the growth and development of any of the component will influence the others. Nature of Interaction 1) Complementary: In a system, if the tree and the crop component help each other, by creating favorable conditions for their growth in such a way that the agro forestry system provides a greater yield than the yield of their corresponding sole crops then it is called complementary interaction. It may be either spatial or temporal. 2) Supplementary: If two components interact in such a way that yield of one component exceeds yield corresponding to its solo crop without affecting yield of the other component, the interaction is known to be supplementary. For example, if the fodder yields from a tree is 20kg/tree and crop yield is 2 tones/ha when grown separately but under agro forestry, the fodder (forage) yield from tree increased to 30 kg/tree without any reduction of crop yield, the interaction is supplementary in nature. 3) Competitive: In this system, the tree and crop components interact in such a way that increase in the yield of one component leads to decrease in the yield of other component due to competitive interaction. As in the example of supplementary interaction, if the fodder yields of tree increases 30 kg/tree but crop yield is reduced to 1.5 tones/ha or the crop yield increases to 2.5 tones/ha but forage decreases to 15 kg/tree. The interaction is competitive in nature. Factors affecting interaction: 1) Effect of species The growth pattern varies from species to species and accordingly affects relationship with associated components. Some crop may perform well in association with particular tree component, whereas the yield of other crops may reduce with the same tree component, because different crops interact differently with the same tree component. 2) Effect density Canopy cover of trees intercepts light depending upon the density of trees and consequently affects performance of underground crops. Generally, yield of underground crop decrease with increasing density of trees. Trees also modify microclimate of crops grown below and improve physical conditions and fertility of the soil. 3) Effect of age The demand for various growth resources and therefore competition affected by the components would be affected by age and growth of the components. Tree takes long time to attain full size and stature, and thus no row space initially. Nevertheless, as the tree grows, their effect on crop growth becomes apparent. 4) Effect of side factors Climate, edaphic and physiographic features of an area affect plant growth, which varies in different species and consequently interactive relationship of component species in an agro forestry system also varies. For example, at one site highest mean forage yield was recorded in association with Leucaenaleucocephala and at the other site, it was lowest in this combination. Variation in rainfall also affects interactive relation of the components. 5) Effect of management Various management practices may be adopted to favorably alter interactive relationship in agro forestry situation. A tree species with all the desired characteristics is not available, tree crowns and roots can be manipulated through management operations, mainly by pruning and thinning. Different management options are as follows: i. Microclimate amelioration ii. Fertilization iii. Application of mulch or manure iv. Irrigation v. Soil tillage vi. Adapted species vii. Supplemental feeding These are for increasing growth whereas for decreasing growth are:- i. Pruning ii. Pollarding (cut off the top and branches of a tree to encourage new growth at the top.) iii. Root pruning iv. Trenching v. Excess shading vi. Herbicide application vii. Grazing/browsing Types of interaction The major types of interaction between tree and crop components in an agro forestry system can be classified as: 1) Positive (beneficial) & 2) Negative (harmful) 1) Positive interactions a) Increased productivity b) Improved soil fertility c) Natural cycling b) Soil conservation e) Water conservation f) Wood control g) Microclimate improvement 2) Negative interactions a) Competition b) Allelopathy c) Pest and Disease Methods for Quantifying Interactions Tree crop interactions depend upon availability of growth resources, site conditions and moisture/ nutrient status of site. In mixed cropping system many indices such as aggressivity,competition ratio, land equivalent ratio, relative crowding coefficient have been used to quantify interaction.. 1) Land Equivalent ratio LER = LER = 1, no advantage >1, beneficial 50 % , other Quercusspp 75 % etc. Solid Volume of firewood Stacked Volume is not the actual volume of fuels. This value of fuel is based on the solid content. The solid volume of firewood depends upon the factors such as stacking, form of billets, length and diameter of the billets. The solid volume can be assessed by any one of the following ways; a) Xylometric metric method Xylometric is a graduated vessel and volume of wood is calculated by the principle of water displacement. The wood pieces are submerged in the water in the vessel. The volume increment in the vessel gives the actual solid volume of wood. As the stack volume is huge, a sample portion is utilized and results extrapolated (estimate on the basis of data available) for the whole log using the formulae given; V=(W*v)/w or W/w=V/v Where, W= weight of the whole stack w=weight of the submerged pieces V=Volume of the whole stack v=Volume of sample taken b) Specific gravity method This is the ratio of the density of a substance to that of water. Actually it is relative density (mass of the unit volume of a substance i.e kg/cubic meter, gram/cubic centimeter or pound cubic foot). The fuel wood weight is calculated by using the relationship between the specific gravity and volume of the wood. Volume (V) = (Weight)/(Specific gravity) or SG=V/W Assignment: 1. What is tree crop interaction ? Explain its nature and affecting factors for crop 2. Calculate volume and total cost of the following logs at the saw-mill; if the sawing cost is Rs. 30/ft3 Log no Girth(inch) Length(ft) Volume(ft3) Cost Rs. 1 45 11 ? ? 2 66 7 ? ? 3 57 5 ? ? 4 69 8 ? ? 5 79 6 ? ? 3. Calculate the volume of a log whose length is 20 m and diameter measurement was d1=50cm, d2=45 cm, d3=40 cm 4. Calculate the diameter at the mid-section of a log from the following. Volume=2.6m3, gb= 0.160m2, gt= 0.120m2 5. Calculate the third diameter of Meliaazadarach from the given information; dCom=80.5cm , d 1=40 cm , d2=50 cm , d3=?? Lect-9 & 10 SOIL MANAGEMENT UNDER AGROFORESTRY SYSTEM (AFS) Introduction Degradation of natural resource viz soil, water, forest and climate is a major problems in modern agriculture. Out of which the soil and water the degradation to cause thread under sustainability of agriculture because decline productivity, profitability, imbalance in ecological system and environmental security. All these problems can be addressing through Agro forestry, it is viable option to maintain agriculture sustainability. Proper land use planning is important for increasing agricultural production, environm

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