Environmental Management: Sustainable Energy Supplies PDF

Summary

This document provides an overview of sustainable energy supplies, including renewable and non-renewable sources, and their environmental implications. It discusses the advantages and disadvantages of different energy types and related environmental impacts.

Full Transcript

ENVIRONMENTAL MANAGEMENT SUSTAINABLE ENERGY SUPPLIES RESOURCE: A concept employed to denote sources of human satisfaction, wealth or strength. Labour entrepreneurial skills, investment funds, fixed capital assets, technology and cultural as well as physical attributes may all be referred to as res...

ENVIRONMENTAL MANAGEMENT SUSTAINABLE ENERGY SUPPLIES RESOURCE: A concept employed to denote sources of human satisfaction, wealth or strength. Labour entrepreneurial skills, investment funds, fixed capital assets, technology and cultural as well as physical attributes may all be referred to as resources of a nation. (Dictionary of Human Geography 1994) Resources are therefore environmental features which are needed and used by people. There are natural resources eg: climate, water and soil as well as human resource eg: population and capital. ENERGY is the ability to do work, it is required for domestic heating and lighting, for transport and for running machineries in manufacturing industries. Energy is a natural resource and sources of energy are either renewable or non-renewable. RENEWABLE SOURCES OF ENERGY: These are also called alternative energy. They are sustainable and always in continual supply. They can be used continually without exhaustion. They are forces of nature ie: self-generating. They are called alternative because they offer an alternative to fossil fuels and nuclear energy that have more environmental effects. Though sustainable, careless use and overuse can affect, degrade or reduce the source of its value. Renewable resources are those which naturally regenerate within a human defined timespan to provide new supplies of those resources. Renewable sources of energy include H.E.P, solar, wind, Biomass (vegetation waste), Geothermal (Heat from the earth ) and tidal/wave energy. Sustainable energy resources are those that while being produced and utilised, satisfy the needs not only for today but also for tomorrow, without also compromising the quality of the environment; their supply is continuous (infinite), and production and utilisation does not cause environmental degradation. For example H.E.P, solar, wind geothermal etc.... Environmental Implications of Renewable Energy The huge advantage of renewable sources of energy is that they are based upon sources which will not run out. Unlike coal, oil and gas, which will certainly run out (and become much more expensive as they be.g.in to run out), the sun, wind, waves and heat from the earth‟s core will never stop or run out. Theoretically, the use of renewables therefore potentially solves all of our energy requirement problems. However, this is certainly not the case yet and there are serious technological and practical problems to be overcome before renewables can even be.g.in to replace conventional sources, that is fossil fuels and nuclear. The major environmental argument for renewables is that they decrease our need to use fossil fuels and nuclear sources. All fossil fuels contain carbon, so SALS 2024 Page 1 burning them inevitably releases carbon dioxide - a major contributor to the enhanced greenhouse effect. Combustion of fossil fuels usually also releases sulphur dioxide and nitrogen dioxide, which are making the natural problem of acid rain much more serious. The environmental problems of fossil fuels do not only stem from their combustion. Coal mines are important sources of air and water pollution, subsidence and dereliction. Oil extraction and transport pollutes the seabed, the sea and, through leakage or catastrophe, coastlines, habitats and wildlife. The use of uranium in nuclear energy generation produces wastes which will remain lethally radioactive for centuries. Radioactive discharges to the atmosphere and to the oceans may also cause serious environmental harm. Thus, the use of renewables potentially reduces all of these environmental problems. However, it is worthwhile remembering that all forms of energy generation cause pollution. The manufacture of generating plant – whether it be a nuclear power plant or a wind farm - uses energy and raw materials, as does the maintenance of energy storage and transmission facilities. Renewable sources such as tidal and hydro-electric have huge ecological effects, as well as significant visual effects on the landscape. By altering estuarine or hydrological regimes, their environmental effects may radiate hundreds of miles away from their sites. Unfortunately, these problems are not as well understood as those caused by gaseous emissions. Thus, it is important to realise that renewable sources of energy may not be as environmentally benign as their supporters sometimes claim. Table 1 below, summarises the major forms of renewable energy. Table 2 summarises the environmental impact of renewable forms of energy. Table 1 SALS 2024 Page 2 Table 2 SALS 2024 Page 3 NON-RENEWABLE SOURCES OF ENERGY These are energy sources that get used up (exhausted) and cannot be replaced in the same natural process and time scale. They take long to form and to be replaced, hence are not sustainable. They consist of fossil fuels (coal, oil, natural gas), nuclear energy (from uranium) and fuelwood. Nuclear and fuelwood are not fossil fuels. Non- renewable such as minerals and land have taken million of years to form and therefore in human terms are fixed in the supply available. SALS 2024 Page 4 RECYCLING: One way to increase the quantity of resource is by recycling the product made from it. For example, scrap replaces some iron ore input in the steel industry. Due to technological advances it is now possible to recover mineral content from the residue dumped from earlier lead and tin mining. Up to 1980’s, only about 10% of household and industrial waste was recycled but with greater awareness of conservation and health hazards of waste dumping, the percentage recycled has markedly increased. However the proportion recycled is still very much related to the cost in proportion to the price of the original raw material. Until very recently, the consumption of raw materials and the proportion of products recycled has been governed largely by market forces and the associated underlying concept of progressive economic development which has continually raised levels of consumption. It is most clearly demonstrated by the economic history of Advanced Industrialised countries but now also characterises developing countries especially the Newly Industrialised Countries (NIC’s). Decisions by countries as to which sources of energy to use may depend upon several factors. These include: Availability, quality, life-time and sustainability of the resource. Cost of harnessing and exploiting as well as transporting the source of energy (importing or within a country). For example some types of energy such as oil may be too expensive for the less wealthy countries. Technology needed to harness a source of energy (this may again be beyond some of the less developed countries, for example nuclear energy or may yet have to be developed eg: wave energy. Demand of final user eg: in the less developed countries, energy may be needed mainly for domestic purposes but in more developed countries it is needed for transport, agriculture and industry. Size of the local market to the source. Accessibility of the local market to the source. Political decisions eg: which type of energy to utilise. Competition from other forms of available energy Environment FACTORS AFFECTING LEVELS OF DEMAND FOR SUPPLY OF ENERGY AND BALANCE BETWEEN DIFFERENT SOURCES These factors include: Levels of development SALS 2024 Page 5 Resource endowment Capital Technology Pollution/Environment considerations Energy policy/Government These factors influence decisions by countries as to which source or sources of energy to use/ develop. Levels of development: HICs, industrialised and fast industrialising nations (NICs) have higher energy demands than LICs. In less developed countries, energy demands are mainly for domestic purposes; In HICs the demand is high for transport, agriculture and industry. Resource endowment: The level of supply and balance between different sources of energy depends on energy resource endowment. While some countries have sufficient energy resources both renewable and non renewable, others depends on import of power/energy. Quality and lifetime; and sustainability of the available resource is an important factor. Occurrence of a large, high quality and sustainability energy resource is advantageous to satisfy the demand eg: oil in the Middle East countries is of high quality. Capital: Large amount of capital resource is required for the development of sustainable energy supply eg: for the set up and running of electric power stations, nuclear energy etc...Whereas some LICs may have known/confined energy resources, they remain unexploited/untapped due to lack of financial resources. Multi-national corporation eg: SHELL, MOBIL or CALTEX are responsible for oil exploration and production in many countries that lack capital. HICs have sufficient supply of energy due to availability of capital to develop the available resources; or important for any deficit. LICs lack financial resources and thus their import of energy eg: oil is affected (not enough capital to import sufficient energy resources) and thus as a result it contributes to deficits in supply in LICs. Technology: High level technology is required to harness a sustainable source of energy. LLCs face energy problems due to lack of technology. Development of nuclear energy for example requires high level technology, that is costly. SALS 2024 Page 6 Market: Demand by the final user is determinant on the type of /source of energy to be developed. Levels of development determine the demand of various sources. There is low demand in LICs and high demand in NICs and HICs. The size as well as affluence of the local market is important. A large and affluent population as in HICs is an advantage-demand is high and production of energy is economical. Accessibility of the local market to the source of energy affects demand and supply. Easily accessible sources are more developed eg: oil and natural gas can easily be transported by pipelines over great distances, electricity can also be transmitted over great distances. Pollution or environmental considerations: The environment is adversely affected by the use of some sources of energy like fossil fuels eg: coal and nuclear. There is preference for some sources as compared to others. Generally there is a decline in the use and development of some sources of energy eg; coal and nuclear energy in some HICs due to environmental concerns. Environmental protection may occur due to environmental pressure groups eg: Friends of the Earth. Energy policy: The energy policy adopted by a country is influenced by political decisions, ie: the type of energy to utilize or develop, whether nuclear, solar or H.E.P , whether for natural use or export. Availability of and competition from alternative sources. These factors will be considered in the advantages and disadvantages of each available source. QUESTION TO CONSIDER: For one country whose energy policy you have studied in detail OR For one country that you have studied in detail, discuss the key factors that have influenced its energy strategy.(15 marks) (Assignment-Deadline 23rd July 2012) Example: Seychelles Seychelles energy strategy: Promotes clean energy Use of imported oil and gas Oil for electrical energy generation 5 power stations run by PUC Oil/energy import by SEYPEC; government monopoly in the industry. Very limited use of renewable sources of energy; mainly solar; renewable is undeveloped Supply satisfies the demand SALS 2024 Page 7 The factors influencing Seychelles energy strategy include: Level of technology Capital, cost of production Market, size and affluence of the population Environmental considerations Government policy Resource endowment Availability of alternative sources of energy Level of development (demand) (Research on Seychelles energy policy) NON-RENEWABLE SOURCES OF ENERGY COAL Coal played an important role in the industrial revolution and second half of the 19th century. It provided the basis for industrial revolution in Britain, Western Europe and the USA. Despite its exploitation for almost 2 centuries, it still has far more economically recoverable reserves than any of the other fossil fuels. Improved technology has increased the output per worker, has allowed deeper mining with fewer workers and has made conversion for use as electricity more efficient. In Britain where pit closure began before the 2nd world war and reached a peak in 1960’s, the industry has been drastically scaled down. The social and economic consequences especially in former one industry coal mining villages have been devastating. There have been many reasons for this decline. The most easily accessible deposits have been used up and many of the remaining are dangerous. Cost have increased due to expensive machinery and increased wages. The demand for coal has fallen for industrial use, domestic use and power stations (ie: there has been a lower demand for these 3) British coal had to face increased competition from cheaper imports (USA and Australia) alternative methods of generating electricity and cleaner forms of energy. Political decisions have seen subsidies paid to nuclear power industry and greater investment in gas than coal-fired stations. SALS 2024 Page 8 Green pressures have also led to a decline in coal mining which creates dust and leaves spoil tips, and using coal to produce electricity as this releases sulphur dioxide and carbon dioxide which are blamed for acid rain and the greenhouse effect. In places such as China and India with large reserves and a rapidly growing demand for energy, it is essential to introduce ‘Clean Coal Technologies’ but this will depend upon their development and possibly their funding by the industrialized countries. FACTORS AFFECTING MINING OF COAL Factors affecting mining and production of coal are: Location of mode of occurrence eg: surface occurrence is cheaper to mine by open cast mining but great depth is uneconomical and costly to mine. Relative price of alternative sources of coal and other fuels: In the USA and Australia coal is cheaper as compared to the UK mines. In China there is abundance, hence is preferred for industrialisation despite decline in other places. Location of market and size of market: Coal is mainly used for thermal power generation and also in steel and metal industries. The demand is greatest in industrialised countries and Newly Industrialised countries. Environmental cost and cost of ‘Clean Coal Technology’: It is a pollutant that causes ground pollution and global warming. The use of coal for power generation continues despite the environmental concerns. Clean coal generation is expensive and the use of such technology has to be compared alongside the cost of using alternative sources of fuel. ADVANTAGES OF COAL AS A SOURCE OF ENERGY: Most reserves of coal are projected to last many years, eg: 30 years as compared to other non-renewable sources such as oil that have shorter life time. It can be utilised for a variety of uses such as power generation, domestic heating, industries etc... DISADVANTAGES: Most deposits have become inaccessible eg: in Britain and Germany hence leading to closure. The use of coal causes pollution and contributes to global warming. SALS 2024 Page 9 Deep mining is dangerous as collapse of mines lead to death of workers and open cast mining cause dereliction of land. Coal is heavy and therefore it is bulky to transport. TREND IN THE PRODUCTION AND CONSUMPTION OF COAL Despite environmental concerns of coal, production and consumption, it continues to be a major source of energy in the 21st century especially in HIC’s and NIC’s. While coal production and consumption continues to increase between 1923 and 1925, there was a considerable increase. This increase may be attributed to: The technological advancement towards creating ‘clean coal’ power generation in HIC’s which has reduced the harmful effects/ environmental impacts of coal in power generation (that is, clean coal technology has led to reduced pollution levels in the affected countries). The increase is also attributed to the rise in the demand of coal in the NIC’s of South East Asia where rapid industrialisation is taking place, eg: in South Korea, Singapore, Taiwan etc...where there is a rise in the importation of coal from Australia and USA due to the set up of new power plants. China is the leading producer and consumer of coal and coal supplies 75% of China’s energy needs. The USA and Australia are self-sufficient in coal and they export their surplus to other countries such as Western Europe. West European countries do have large coal reserves but they import coal because it is relatively cheaper. In LIC’s coal is less important basically because of the low demand due to low level of industrialisation. LIC’s consume only 10% of the world coal consumption. Coal consumption in LIC’s may increase in the future as the level of industrialisation increases. Also the availability of capital may enhance production in LIC’s especially the ones where large reserves exist but exploitation has not taken place due to lack of capital. Class Exercise: Refer to page 489 Integrated Approach, Fig 18.2 that shows world energy production, 1990. Which source of energy was the most important in terms of production by 1990 and at what percentage of total world energy production? What differences do you note in world energy production between different world regions How do you account for the differences in energy production between different regions and the balance between various sources? Fig 18.3 shows world energy uses 1950-1990 SALS 2024 Page 10 What is the trend in world energy uses/consumption between 1950 to 1990 Which sources of energy were least consumed and most consumed by 1990 How do you account for the low amount of energy use in 1950 and the rapid increase in consumption by 1990? Account for low rates of change in consumption of coal and nuclear energy by 1990 Refer to fig 18.5 showing location and movement of the world’s fossil fuels What are fossil fuels? What is the general distribution of HICs and LICs Describe the distribution of oil fields, natural gas and coal fields in the world, mention countries. OIL Oil is a non-renewable source of energy and together with natural gas has gradually replaced coal as a major source of energy. Many industrialised countries depend on them. This resource is sparsely distributed, normally in remote, adverse climatic environments eg: deserts, and few countries are self- sufficient. ADVANTAGES OF OIL: It is an efficient source of energy compared to fuelwood etc... It is easier to transport-by tankers and pipelines Relatively less environmental destructive compared to coal. It has a variety of needs/uses- eg: for power generation, heating lighting, transport, agriculture and as a raw material for other industries. DISADVANTAGES: It is a limited resource, located in adverse environments and it has a short lifetime 50-70 years. Oil refineries eg: at port terminals etc takes up large space Oil is highly pollutant-its use causes air pollution, acid rain formation; spillage causes water pollution. Explosion is a danger and can cause loss of life. SALS 2024 Page 11 Prices fluctuate/ vulnerable trade subject to world political and economic conditions; supply and demand hence affected-LEDCs highly affected. FACTORS AFFECTING PRODUCTION/ SUPPLY AND DEMAND OF OIL Location/ Distribution and lifetime of reserves: Remote, hostile environments eg: Alaska, North sea, Deserts etc....Its exploration and exploitation is problematic, and LICs depends on MNCs. Oil also have a short lifetime of reserves; 50-70 years. The Middle East is highly endowed in oil. New technology: This will increase production as less accessible reserves will be exploited eg: North sea. This is expensive. For example drill rigs mounted on platforms are fully equipped with processing and residential place for workers. Location and size of market: It is expensive to transport oil from the remote locations. Demand is high in HICs and NICs, also in LICs due to modernisation. Oil is bulky but can easily be transported by pipelines and oil tankers to the world market. Political and military decisions and government policies: OPEC has greater influence in fixing oil prices and determining production. Political situation in the world eg: Iran-Iraq war (1980’s) and Gulf war (1991) affect oil production and consumption results in oil crisis- often resulting in a shortage and high prices of oil. LICs are usually the most affected. Environmental cost: Though oil is relatively clean, spillage and emissions cause water and air pollution. However, despite the environmental cost, oil production and consumption is on an upward trend. Cost of alternative sources of energy and other sources: The other sources may include natural gas, nuclear, H.E.P and other renewable. In HICs due to environmental concerns, stress is now on renewable. TRENDS IN WORLD OIL PRODUCTION AND CONSUMPTION Production and consumption is increasing slowly both in LICs and HICs. Few countries are self sufficient in oil. The majority of HICs continue to import oil eg USA, Japan and the NICs of S. East Asia. Despite the increase in use of alternative sources of energy eg: H.E.P, oil demand in transport, industry and petro-chemical industries may continue to rise in modern economies. SALS 2024 Page 12 OPEC countries dominate export trade and OECD countries as importers in world oil trade. OECD(Organisation of Economic Corporation and Development). The main producers are the Middle East countries, producing about 40% of world oil, Saudi Arabia ¼ of world trade oil, ½ of world oil is from the Middle East. Other producers include non-OPEC countries and some industrialised countries eg: USA. The increase in production is attributed to: Increased exploration eg: Malaysia and Phillipines, Venezuela and Mexico. Rise in production from countries affected by Gulf war eg: In Kuwait new fields have been opened, and sanctions on Iraq have been lifted. Britain, Norway and other EU countries increased production due to development of old and new fields in the North sea World demand is expanding slowly at an estimated rate of 1.5%. HICs and NICs consume about 70% of world oil mostly in transport sector-especially USA, Japan and OECD. NATURAL GAS It is a non-renewable resource, and a fossil fuel. It is the 3rd largest world primary energy source that has grown recently as a major source of primary energy. The increasing production and consumption of gas is attributed to factors such as: Increased explorations and discovery of non-oil associated gas. Since the 1970’s, gas reserves separate from oil has been discovered. Previously gas was thought to be of lesser importance than oil, hence no efforts had been made to increase production other than rely on the oil associated gas. Natural gas is a non-pollutant fossil fuel. There is increasing demand for natural gas because it is environmentally friendly as compared to other fossil sources such as coal and oil. Increasing environmental concerns has promoted the use of gas. Technological advancements in power generation. The use of improved, efficient gas turbines with higher power production. In Netherlands for example, gas is the most important heating source and future production and consumption will increase. Existence of large reserves worldwide. There is no shortage of gas and the current reserves have lifetime of over 60 years and new reserves are being discovered. Key producers include Middle East, Norway, Netherlands, USA, Algeria etc....In Western Europe and USA gas production has been enhanced to reduce dependence on imported oil and nuclear fuels. It is easy to transport. The location of gas fields in relation to the market is important but does not affect the demand. Transportation over great distances by pipeline and special SALS 2024 Page 13 tankers. The cost of liquefying and transporting is prohibitive on the amount transported/ exported. (prohibitive: too high to be affordable) NUCLEAR ENERGY It is a non-renewable source of energy, a non-fossil fuel produced from uranium. (ie: it uses uranium as its raw material). It contributes about 17% (1995) of world energy supplies. There was a steady rise in the 1980s to 1995, from 8% in 1980 to 17% in 1995, but production is on a downward trend projected to decline to about 13% by 2015. Nuclear energy has the following advantages: It is environmentally friendly compared to fossil fuels; it is clean. It is efficient as small uranium amounts are required to produce sufficient energy as compared to coal. (50 tonnes of uranium a year, compared with 500 tonnes of coal per hour for coal-fired power stations). It has a longer lifetime than coal, oil or gas. It can be utilised in specialised needs eg: space air crafts/shuttles. Its disadvantages include: Though relatively clean, disposal of nuclear waste causes pollution, an issue of concern.(Recent example: Fukushima in Japan 2011) It is dangerous, if there is leakage, exposure leads to death, loss of life eg: Chernobyll incident of 1986. Modern technology aimed at making it safe is very expensive, out of reach for LICs. Decommissioning of ageing nuclear power station is expensive, dangerous and slow. It is expensive to develop compared to other sources. It is exhaustible. Importance of nuclear energy is on the decline especially in HICs; however some countries eg: France have maintained nuclear energy power production. Also for NICs eg: in S.E Asia there is an upward trend in production and consumption. The decline in the importance of nuclear energy is due to: Increasing public opposition to further expansion of nuclear energy. SALS 2024 Page 14 Alternative sources of energy are seen as commercially viable (cheaper) and environmentally friendly. Most HICs of Britain have suspended their nuclear energy programme. Future of nuclear energy depends on technological advances to improve safety aspect and bring down the cost of operation. For industrialising Nations (NICs etc), nuclear energy expansion is necessary to meet their energy requirements eg: S.E Asia. Due to efficiency in production and consumption in HICs, expansion of an expensive source such as nuclear is not necessary. Existing sources are sufficient. TRENDS IN THE PRODUCTION AND CONSUMPTION OF NUCLEAR ENERGY Production and consumption greatly increased in the 1980s but since the mid 1990s it has been on the decline e.g. Britain has suspended its nuclear programmes and even some power stations have been closed down. France has undertaken the usage of nuclear energy as the main source of energy and thus its production and consumption is on the increase there. Production and consumption is also on the rise in the NICs and South East Asia. This global trend in production and consumption is explained in the following ways: 1. The decline in importance in nuclear energy since the mid-1990s is due to increased public opposition to further expansion of nuclear energy especially in HICs such as Britain. This opposition is based on the environmental impact of the production and use of nuclear energy and also due to the fact that nuclear energy is relatively expensive compared to other sources of energy. Nuclear energy is dangerous e.g. the Chernobyl in the Ukraine in 1986 is a constant reminder that the disposal of nuclear waste is a problem. The technology required is expensive and it is also expensive to develop and for decommissioning it. Research about the Chernobyl incident. 2. Increase in production and consumption in the NICs is due to high energy demand for industrialisation since the sources are not sufficient to meet the demand. 3. Production and consumption in Britain has declined due to efficiency in energy production and consumption. It is therefore not necessary to expand or develop an expensive source of energy such as nuclear since the existing sources are sufficient. SALS 2024 Page 15 4. For LICs nuclear energy production and consumption is low e.g. due to lack of or low level technology, lack of capital and low level of development. That is there is low energy demand in LICs. FACTORS THAT INFLUENCE THE LOCATION OF NUCLEAR POWER STATIONS 1. Safety is the key factor: Nuclear power stations should be located away from large population concentration to avoid an impact of possible explosion and leakages since nuclear energy in highly dangerous. 2. Availability of water: Abundant supply of water is required for cooking of reactors. 3.Nuclear waste disposal should be considered since it is also connected to safety and therefore it should be located in distant places to avoid contamination of the environment. 4. Agglomeration advantages, hence, location near the established old reactors is necessary to benefit from established infrastructures. 5. A large and level site (flat land) is required for the establishment of a nuclear power station as well as for any technological advancements or changes. 6. Future locational pattern may change due to technological improvements. Location near old reactors may remain for agglomerating advantages. CASE STUDY: FRANCE Refer to France case study and answer the following questions. Q1. a) What factors have promoted nuclear energy as a major source of energy in France? SALS 2024 Page 16 Describe and account for the distribution of nuclear power plants in France. Account for changes that have occurred in nuclear power production and consumption in the world (refer to specific countries of study). Why is nuclear energy a less important source in LICs? Q2. a) Describe the trend in total internal energy production and consumption in France-refer to graph and case study. b) Conventional thermal energy production is on the decline in France. What are conventional thermal production sources? Suggest reasons for the decline in conventional thermal power production. Q3. a) Discuss the environmental impacts of the production and use of nuclear energy. b) Suggest reasons which can be implemented to deal with the environmental impacts of production and use of nuclear energy. NB: Although nuclear power stations produce fewer greenhouse gases than coal, oil and gas-fired power stations, nuclear power stations do present potential risks in 3 main areas and that is: Routine emissions of radioactivity Waste disposal Radioactive contamination accidents: eg; routine emissions have been linked with increased case of leukaemia. REVISION QUESTIONS 1) What considerations affect the relative balance of coal, gas, oil, HEP and nuclear power as sources of electrical energy in any countries you have studied? 2) With reference to any one country you have studied, discuss the location and methods of power production (e.g.: Seychelles). 3) With reference to examples, comment briefly on how each of the following have affected the coal mining activities a) Geological structure SALS 2024 Page 17 b) Production and quality of coal produced c) Location of the coal mines in relation to the market d) Cost and availability of transport. SALS 2024 Page 18 ENVIRONMENTAL DEGRADATION DEGRADATION OF RURAL ENVIRONMENTS: The quality of rural environments may be affected or degraded to an extent that its ability to sustain life decreases. There are different causes of rural degradation include: Poor agricultural practices such as over-cropping, application of fertilizers and chemicals, shifting cultivation on steep slopes, overgrazing, poor irrigation techniques etc... Deforestation Mining: Case study-Zambian Copper Belt. Desertification Industrialisation Political Instability Degradation due to poor agricultural practices: Shifting cultivation leads to soil erosion and loss of nutrients. Over application of fertilizers and other irrigation practices may lead to a rise in the water table and thus cause salinisation. The use of heavy agricultural machinery leads to compaction of the soil. It affects soil hydrology and causes physical deterioration. Monocropping and overcultivation without allowing a fallow period leads to soil exhaustion. Cultivation of steep hillslopes without adequate preventive measures leads to soil erosion. Nomadic pastoralism with overstocking causes a destruction of vegetation and with the burning of pastures, leads to soil erosion. Such practices for eg, in the Sahel region have led to widespread soil erosion, decrease in soil fertility and productivity hence a decline in food production or agricultural output, frequent famine, desertification, outmigration etc..... Desertification: Desertification is the the spread of desert or desert-like conditions induced by human activities, and some natural/physical factors. It is also called ‘desertization’ eg, the Sahara desert is gradually spreading southwards in Africa (desertification in the Sahel region). The causes of desertification include: SALS 2024 Page 19 Vegetation clearance: Deforestation due to human activities, overgrazing, poor farming practices eg: shifting cultivation etc....all of these activities leave the ground bare and lead to soil erosion. Climatic change: This is both a natural phenomenon and a human induced one eg: in the Sahel region very bad rainfall conditions and a gradual increase in global temperature have led to prolonged drought. Global warming is a human induced phenomenon which has gradually increased due to deforestation and the increased use of fossil fuels that lead to the increase of greenhouse gases in the atmosphere. In the Sahel region there was severe drought between 1968 to 1984 and it continues today in some areas. NB: Areas which have experienced desertification are generally characterized by high temperature and inadequate amount of rainfall.. The physical characteristics of some regions eg: soil type, vegetation characteristics and hydrological factors contributes to desertification. Eg: Areas with relict soil that are highly porous, low biomass development and lack of adequate water resources. Population increase especially in the Sub-Saharan Africa is due to the high rates of natural increase and this leads to over-exploitation of resources such as water and forest and in most places such resources have been depleted which upsets the ecological balance. In the Sahel region eg: the high number of refugees has caused destruction of vegetation due to the high demand for fuelwood and construction material. Effects of desertification eg: Sahel Region Such effects have been noted in countries such as Chad, Sierra Leone etc.... Decreased agricultural production due to loss of soil fertility. Loss of grazing and agricultural land as deserts spreads outwards. Frequent food shortages and famine eg: Ethiopia Outmigration from affected areas and an increase in the number of displaced persons and refugees eg: in Sudan Loss of genetic resources (endemic species of plants and animals). Physical and mental stress (psychological suffering ie: people generally have poor health). The cost of rehabilitation or reclamation is very high. The attempted solution: SALS 2024 Page 20 Afforestation /Reforestation: Programs with drought resistant trees to reduce soil erosion and improve the hydrology of such areas. Controlled grazing: Ranching especially amongst the pastoralist community. Encouraging nomadic pastoralists such as the Masai whereby schemes to provide the basic services and amenities would be set up. Their housing standards could also be improved and they could be educated about alternative economic activities alongside pastoralism. Improving water supply in the marginal or semi-arid areas eg: by building dams or by digging of bore holes to sustain other economic activities. Irrigation schemes in the arid and semi-arid areas. Stock reduction among the pastoralists to avoid overgrazing. Establishments of wind break to reduce wind erosion and dust storms in the surrounding areas. Sand dune stabilisation eg: by planting of vegetation to stop wind erosion. Chemical treatment in the soil eg: use of fertilisers to restore soil fertility in the affected areas. Increasing water retention capacity of soils eg: through the process of mulching ie: the use of leaves to stop evaporation. Utilisation of wild species of plants and animals and the increased use of drought resistant species of plants and animals. Aid eg: food aid in the famine stricken areas, finance or technological aid or material aid eg: seedlings, fertilisers etc...to countries such as those found in the Sahel region which lacks the ability to deal with desertification. NB: Desertification is a global environmental problem since it is loosely linked to climatic change hence there is the need for international consultative meetings and research in order to reach a global solution. Refer to Integrated Approach for case study on Desertification. Mining: Mining plays an important role in a country’s economy. However mineral extraction without proper management may lead to degradation of rural environments. Some of the negative impacts associated with mining include: Open cast mining causes dereliction of land by stripping off the landscape fertile soil and leaving behind ugly scars on the landscape. SALS 2024 Page 21 It causes destruction of vegetation (deforestation). Mining creates mine tips which can be hazardous when mass movement occurs. It leads to air pollution due to large amount of dust that is produced. It contributes to water pollution, especially rivers when panning methods are involved eg: alluvial mining. The abandoned mining tips can also be environmental hazards and may act as hiding places for criminals. Mining is associated with certain respiratory diseases such TB due to inhaling of toxic gases and dust. Exhaustion and the abandoning of mining leads to economic decline eg: rise in unemployment. Derelict land may not support other activities without treatment. The cost of reclamation is generally very high. CASE STUDY Upgrading of a degraded rural environment Copper mining has played a key role in the Zambian Economy since independence. The negative impacts of mining have been recognised in the copper belt. The derelict land may not be utilised for any other use without treatment or reclamation. Restoration of derelict land to its original state is often not possible. It is a slow and costly exercise which is normally beyond financial and technical abilities of developing countries such as Zambia. In Zambia, the Zambian Environmental Council (ZEC) is responsible for the monitoring of environmental impacts and the implementation of upgrading the derelict land. This project has been sponsored by Scandinavian Government. Apart from financial and technical constraints, land ownership of the mining areas is also a problem. Much of the land is owned by MNC’s hence it is protected and the Zambian Environmental Council does not have a right to reclaim it. The various strategies or measure adopted include: Pollution control measures eg: mining factories are composed to install filters to cut down the amount of emission further to the atmosphere. Filling up of abandoned mine pits by using the mine tips, soil and rocks that was stripped off the surface. Afforestation and re-afforestation programs (the greening of the environment). SALS 2024 Page 22 Contracting other companies to carry out recycling of the mine tips. The government is providing incentives to investors so as to create more employment opportunities in areas where mineral exhaustion has occurred, therefore to avoid economic decline. Deforestation: Deforestation is the temporary or permanent clearance of forests which occurs when forests are replaced by another land use such as settlement, agriculture etc...Deforestation is a global environmental problem since it is associated with various negative impacts. The impacts of deforestation include: It leads to widespread soil erosion due to lack of vegetation cover and hence limited interception eg: in the Sahel region thus leading to physical degradation of the environment. It leads to loss of genetic species of plants and animals. It contributes largely to global warming hence contributing to climatic change. Forests are lungs of the earth and deforestation leads to increased accumulation of carbon dioxide in the atmosphere and carbon dioxide is a key greenhouse gas. Deforestation leads to changes in the heat balance, the water budget and albedo. Deforestation leads to shortage of forest resources in the future eg: timber since the rate of deforestation is higher than that of forest regeneration. Deforestation is a major cause of desertification (desert-like condition) eg: in the Sahel region of Africa. Deforestation increases flooding risk since interception is reduced and overland flow increases. It increases the sediment content in the rivers thus affecting the water quality. THE PROCESS OF DEFORESTATION Eg: In the Amazon rainforest. Conversion of land to agricultural land use. Due to increase in population, the demand for food has increased, hence the need to increase the area under cultivation. This also incorporates annual ranching and activities such as nomadic pastoralism. Commercial logging (forestry). The increase in timber and forest products has led to massive clearance of forests in areas such as the Amazon and South West Australia. Such activities are carried out without control. Settlements and other infrastructural development. This has also occurred due to population growth and due to economic development. The construction of towns and highways also contributes to deforestation. SALS 2024 Page 23 Mining eg: the extraction of oil in areas such as the Amazon also leads to deforestation. Charcoal production and the high demand for fuelwood in LIC’s also leads to deforestation. WAYS OF DEALING WITH DEFORESTATION Afforestation and re-afforestation programs. The use of alternative sources of energy. Practicing agro-forestry ie: planting of trees alongside crops on the same piece of land. Controlling logging eg: through licensing of the logging companies. Stricter environmental laws to protect forests eg: increase the fines and jail terms for illegal logging. Setting up natural reserves with strict laws and security. Campaigns to increase public awareness on the dangers of deforestation. KEY QUESTIONS: Define the term deforestation With reference to locational examples, describe the main causes of deforestation. What are the main effects of deforestation? Suggest ways of dealing with deforestation. Refer to Integrated Approach for case study on Deforestation (Forest of South West Australia). DEGRADATION OF URBAN ENVIRONMENTS: SALS 2024 Page 24 The quality of urban environments may be affected (degraded) to an extent that its ability to sustain life decreases as is the case for rural environments. The living standard has declined due to degradation of these environments, eg: Inner cities in HIC’s and shanty towns in LIC’s. Generally the quality of urban environments may be affected by the following factors: Urbanisation Industrial developments Inadequate infrastructure War Natural hazards etc.... These factors have led to various urban problems, especially in developing cities such as Cairo (Egypt), Mexico city and Mumbai (India). The urban problems are symptoms or indicators of environmental degradation. The urban problems that are more pronounced in Inner cities in HIC’s and shanty towns in LIC’s are: Overcrowding/Congestion Traffic problems such as congestion and long distance commuting Rising pollution levels Housing shortage High unemployment Crime/Insecurity Poor services Social problems Many cities in LIC’s are unsustainable environments. Degradation due to Urbanisation SALS 2024 Page 25 The process of urbanisation occurred in HIC’s in the 19th century due to Industrial Revolution. This was associated with establishment of manufacturing industries such as iron and steel, textile and coal mining. Due to migrations into cities such as London, and high natural increase in those cities, the urban population grew rapidly. The Inner cities such as London’s Docklands developed several diseconomies; declining environmental conditions which acted as push factors, thus suburbanisation occurred leading to urban sprawl. (note urban problems) In LIC’s, rapid urbanisation has occurred in the 20th century, since the 1950’; this has been attributed to mainly rural-urban migration. Urbanisation in LIC’s has led to rapid growth of large cities such as Lagos (Nigeria), Mexico City(Mexico), Beijing (China), Sao Paolo(Brazil) etc........Most of these cities are associated with rapid urbanisation. Eg: Concentration of large population due to influx of migrants into cities; the increasing volume of traffic leads to overcrowding; together with development of industries lead to high pollution levels. It leads to housing shortage and consequently emergence of shanty towns. As these cities grow in space and population size they become too unsuitable; it is increasingly difficult to provide sufficient amenities and services. ii.Degradation due to Industrial developments: HIC’s and NIIC’s have many large industrial conurbations. Such industrial/manufacturing activities include textile, petro-chemical industries etc....... Most of these countries are dependent on fossil fuels such as coal and oil thus they are the main sources of pollutants such as sulphur dioxide, carbon dioxide etc...; urban areas are thus some of the highly polluted environments. These pollutants contribute to formation of smog eg: in Los Angeles (smog city). The manufacturing industries are also sources of thermal pollution, noise, water as well as air pollution. SALS 2024 Page 26 This greatly affected the inner cities in HIC’s eg: in North West England, Manchester, West Midlands etc..... In recent years, re-industrialisation has occurred for example due to closure of mines (exhaustion of resources) and change of technology. Traditional industries such as the textile industry has either closed down or relocated. Dereliction has occurred as old industrial properties eg: buildings are abandoned such as in Wolverhampton. Such declining urban environments also experienced declining economic conditions, unemployment and out migration. Inadequate infrastructure: This is a great problem in developing cities such as Cairo (Egypt) Though urban problems are attributed mainly to rapid urbanisation in LIC’s, there are other contributing factors eg: lack of capital, lack of space, poor planning policies etc... Most developing cities such as Cairo are characterised by poor and inadequate transport, traffic congestion, housing shortages, lack of adequate clean water supply, frequent power shortages, insecurity etc... Such problems are more pronounced in the shanty town and the inner cities. These problems are key indicators of urban deprivation since they lead to a declining standard of living in cities. In the UK for example, poor planning policies led to large scale demolitions of housing estates fro redevelopment. However the projects were not accomplished eg: in Manchester (1950-1970s). This led to dereliction. War as a cause of urban degradation: Political instability eg: war in the Middle East (Iraq, Lebanon etc..) and some countries such as Somali, Sierra Leone, Liberia etc.. leads to destruction of important infrastructures such as buildings and bridges etc. It also causes disruption of power supply, transport, water supply etc... and even destroy industries. Recently it was noted that Liberia’s capital city-Monrovia, had gone without piped water for over 12 years due to civil war. This also affects provision of essential services such as education and medical. SALS 2024 Page 27 War also causes loss of workforce either through death or emigration. This affects provisions of services and leads to economic stagnation. It causes fear among the residents and decline of living standards as carrying capacity falls. It is very costly to restore these environments to their desirable conditions. SALS 2024 Page 28 SALS 2024 Page 29

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