Soil Science Concepts & Definitions PDF

Ecosystem Fundamental Concepts and Definitions A community or group of livin...

Ecosystem Fundamental Concepts and Definitions A community or group of living organisms that live in and interact with each other in a specific environment. Unit I For instance, tropical forests are ecosystems made up of living Chelly S. Alovera beings such as trees, plants, animals, insects and micro- Department of Soil Science College of Agriculture Central Mindanao University organisms that are in constant interaction between themselves and that are affected by other physical (sun, temperature) or chemical (oxygen or nutrients) components. soils40csalovera Fundamental Concepts and Definition Global Ecosystem 1. Components of the global ecosystem 2. The pedosphere  is a systematic, complete, and organically connected whole 3. Definition of soil Hierarchy of study of soil dimensions & boundaries 4.  contains millions of species of organisms arrayed in a very 5. Importance and functions of soils complex pattern driven by many interacting physical 6. Concepts of the study of soil environmental factors, plant nutrients and other chemical 7. History of Soil Science factors, competition between organisms, predation, human 8. Divisions of Soil Science disturbance, and other biotic interactions. soils40csalovera soils40csalovera Chelly S. Alovera, Department of Soil Science,  Global Ecosystem Pedosphere In order  is the outermost layer of earth that is composed of soil and is to survive, ecosystems subject to processes involved in soil formation need five basic components (biotic & abiotic): energy,  is the skin of the earth and only develops when there is a mineral nutrients, water, dynamic interaction between the atmosphere, biosphere, oxygen, and living organisms. lithosphere, and the hydrosphere Most of the energy of an ecosystem comes from  is the foundation of terrestrial life on earth soils40csalovera the sun. soils40csalovera Earth’s Subsystems The Pedosphere  these subsystems are known as “spheres” Represents as the  abiotic and biotic spheres intersection of the  Four major spheres: lithosphere, lithosphere, hydrosphere, atmosphere (abiotic) atmosphere, biosphere (biotic) hydrosphere, and biosphere  Additional sphere: pedosphere soils40csalovera soils40csalovera Brady and Weil, 2017 Chelly S. Alovera, Department of Soil Science,  Hierarchy of Study of Soil Dimensions and Boundaries  Soil does not appear as discrete individual but rather as a kind of continuum varying from place to place reflecting changing soil-forming conditions Brady and Weil, 2017 At the kilometer scale (a), soil participates in global cycles of rock weathering, atmospheric gas changes, water storage and partitioning, and the  Soil properties change gradually over distance life of terrestrial ecosystems. At the meter scale (b), soil forms a transition zone between the hard rock below and the atmosphere above—a zone through which surface water and groundwater flow and in which plants and other living organisms thrive. A thousand times smaller, at the  A boundary of one soil is also a boundary of another millimeter scale (c), mineral particles form the skeleton of the soil that defines pore spaces, some filled with air and some with water, in which tiny creatures lead their lives. Finally, at the micrometer and nanometer scales (d), soil minerals (lithosphere) provide charges, reactive surfaces that soil, but it is usually diffuse over some tens of meters and adsorb water and cations dissolved in water (hydrosphere), gases (atmosphere), and bacteria and complex humus macromolecules (biosphere). is only rarely obvious soils40csalovera soils40csalovera Hierarchy of Study of What is Soil? Soil Dimensions and Boundaries  The problem of identifying soil individuals was  is a dynamic natural body formed from the weathering of provisionally answered by considering common rocks and minerals (and decomposition of organic materials), characteristics or properties of soil composed of organic matter, mineral matter , air and water,  Soil taxonomy is a hierarchy soil classification system and possesses distinct characteristics and properties which in with six categories, or levels: turn influence plant growth. Order, Suborder, Great group, Subgroup, Family and Series soils40csalovera soils40csalovera Chelly S. Alovera, Department of Soil Science,  Differentiating Characteristics of the Categories Number Category Nature of differentiating characteristics of taxa Subgroups >1,300 Properties indicating intergradations to other great groups, suborders, and orders, extra gradation to “not soil” Family >8,000 Properties important for plant growth; broad textural classes; mineralogical classes; soil temperature classes Series Physical properties; chemical and mineralogical properties of the horizons 348 (Philippines) soils40csalovera Differentiating Characteristics of the Categories Number Category of taxa Nature of differentiating characteristics 5 Key roles Order 12 Soil forming processes as indicated by the of soil presence or absence of major diagnostic horizon Uses of soil as a Suborder >50 Subdivision of orders according to presence or natural resource absence of properties, moisture regimes, major parent material and vegetational effects Great >240 Division of suborders according to similar kind, groups arrangement and degree of expression of horizons soils40csalovera Google Chelly S. Alovera, Department of Soil Science,  3. Soil as a medium for waste disposal 1. Soil as a medium for plant growth and nutrient cycling Plants growing on land depend on the soil for water and nutrient elements.  Household wastes  Farm wastes  Food for human beings  Industrial wastes Plants  Feeds for animals that can  Medicine Soil is a very important component in be used  Clothing the natural cycle of carbon, nitrogen as: and sulfur.  Shelter soils40csalovera soils40csalovera 2. Soil as a system that holds and purifies water 4. Soil as a habitat for soil organisms Water for drinking  Agent of organic matter decomposition  Source of antibiotics  Soil mixing - pedoturbation Water for crops soils40csalovera soils40csalovera Chelly S. Alovera, Department of Soil Science,  5. Soil as an engineering medium Concepts in the study of soil science Soil is the foundation for the construction of a. Pedological approach buildings, bridges, irrigation canals, roads, septic “Theoretical Approach” tank and recreation facilities. The soil is considered as a natural body with major emphasis on properties related to its genesis and classification as it occurs in its environments. The information gathered by the pedologist would be of interest to road and building contractors or highway soils40csalovera engineers. soils40csalovera What is Soil Science? Concepts in the study of soil science Soil science deals with the study of soils as a natural resource on the surface of the earth which includes: b. Edaphological approach “Practical Approach”  soil formation  classification and mapping  Physical and chemical properties Considers the physical, chemical and biological  biological and fertility properties properties of the soil as they relate to crop production.  properties in relation to their management for The information gathered by the edaphologist would be crop production of interest to farmers, agriculturists and foresters. soils40csalovera soils40csalovera Chelly S. Alovera, Department of Soil Science,  History of Soil Science History of Soil Science Teoharov, 2017 Teoharov, 2017 An international contact of soil scientists was The science of soils was first established in 1908, when Russian, founded under the name Hungarian and Rumanian scientists got pedology by the world- together and planned the organization of First joint scientific excursions. They decided to famous Russian soil International hold the first international forum in Hungary. The Beginning scientist V.V. Dokuchaev 140 years ago - after he Conferences In 1909 the First International Agronomical wrote the major work and Pedology Conference was held in Budapest. In 1910 in Stockholm at the Second “Russian Chernozem” in Congresses 1883. International Pedology Conference a decision was made to publish an international soil science journal which was released in 1911. soils40csalovera soils40csalovera History of Soil Science History of Soil Science Teoharov, 2017 Teoharov, 2017 The soil scientists in France accepted a lot of An international contact of soil scientists was the Dokuchaev‟s concepts, terms and ideas first established in 1908, when Russian, Development and published their first national soil map in Hungarian and Rumanian scientists got of Soil Science 1838. In 1927 in America the first taxonomic together and planned the organization of First joint scientific excursions. They decided to in the First Half grouping of the soils from Marbut was also made and it corresponded to the genetic soil International hold the first international forum in Hungary. of the 20th types, introduced by Dokuchaev. Conferences In 1909 the First International Agronomical Century in Pedology Conference was held in Budapest. and Europe and In 1910 in Stockholm at the Second Soil science was acknowledged as an Congresses America International Pedology Conference a agronomical science. decision was made to publish an international soil science journal which was released in 1911. soils40csalovera soils40csalovera Chelly S. Alovera, Department of Soil Science,  History of Soil Science in the Philippines Divisions or fields of specialization  1903: C.W. Dorsey (an American) conducted the first survey in the in soil science Philippines  1921: Division of Soil and Fertilizer under the Bureau of Science b. Soil Microbiology was created  1934: renamed as Division of Soil Survey Deals on the study of major groups of soil  1951: Philippine Congress enacted R.A. 622 organizing the Bureau microorganisms, their ecology and of Soil Conservation with Dr. M.M. Alicante as its first director biochemical activities in relation to soil fertility.  As early as 1920s: Teaching of soil science was started at the University of the Philippines College of Agriculture (UPCA) soils40csalovera soils40csalovera Divisions or fields of specialization Divisions or fields of specialization in soil science in soil science a. Soil Fertility c. Soil Conservation and Management Deals on the study of the inherent capacity of Deals with the study of soil deterioration and its the soil to supply nutrient elements and their control, maintenance and improvement of soil availability, evaluation of soil fertility status, use fertility and productivity. of fertilizer and soil amendments. soils40csalovera soils40csalovera Chelly S. Alovera, Department of Soil Science,  Divisions or fields of specialization Divisions or fields of specialization in soil science in soil science d. Soil Chemistry f. Soil Survey and Classification Deals with the chemical constitution of soils, Deals with the systematic examination of the chemical properties and processes, chemical soils in the field or lab, their description, reactions and ionic equilibria and study of classification, mapping and interpretation submerged soils. according to their suitability for different management systems. soils40csalovera soils40csalovera Divisions or fields of specialization Divisions or fields of specialization in soil science in soil science e. Soil Physics g. Soil Genesis (Pedology) Deals with the physical properties of soils in Deals with the weathering of rocks and relation to plant growth with emphasis on the minerals and soil-forming factors and state and transport of matter in the soil processes. especially water and energy. soils40csalovera soils40csalovera Chelly S. Alovera, Department of Soil Science,  Divisions or fields of specialization in soil science h. Soil Mineralogy Deals with the primary and secondary soil minerals and their contribution to the chemistry, physics, fertility and biology of the soils and their relation to soil genesis. soils40csalovera Chelly S. Alovera, Department of Soil Science,