Soil Resources PDF

Senior High School De La Salle University - Dasmariñas Soil Resources ´ Soil is an essential component of Earth that enabled life to exist on the planet and continues to support it. It forms the Pedosphere (Gk. “pedon” which means soil and “sfaira” which means sphere) which is the foun...

Senior High School De La Salle University - Dasmariñas Soil Resources ´ Soil is an essential component of Earth that enabled life to exist on the planet and continues to support it. It forms the Pedosphere (Gk. “pedon” which means soil and “sfaira” which means sphere) which is the foundation of terrestrial life on this planet. ´ The pedosphere is the living skin of Earth which is a result of the dynamic interaction among the four subsystems.  ´ Is made from portions of the geosphere, atmosphere, hydrosphere, and biosphere. ´ COMPONENTS ´ 45% Mineral ´ 25% Air © Research Gate ´ 25% Water ´ 5% Organic Matter (roots, dead and decaying matter) ´ SOIL FORMATION – forms when rock weathers (chemical or physical). It could be a slow or rapid process depending on the factors at play. There are 5 factors affecting soil formation. ´ Parent Material – its chemistry and type will determine the kind of soil it will form along with the effects of other factors. ´ Climate – temperature, rainfall, and moisture affects the pattern and intensity of soil forming processes such as weathering, leaching, transportation, and distribution. Climate also affects the type of organisms, bio activity, and rates of chem. reactions. ´ Topography – slope affects water flow and erosion. Steep slope à thinner soils due to high rate of erosion. Slope aspect, affects temperature and moisture. ´ Biological Factors - burrowing, biological weathering, nutrient and chemical exchange between roots and soil, agriculture and urbanization. ´ Time ´ SOIL TEXTURE – is the relative proportion of the particle sizes in the soil – sand, silt, clay. Soil is naturally composed of these particles and proportion of which affects soil properties such as soil porosity and water retention. ´ Clay is the smallest particle at (75.00mm. ´ Soil formation is a gradual process which involves the development of succession of zones or soil horizons. Each horizon has a distinct set of physical, chemical, and biological characteristics. ´ Soil scientists use the capital letters O, A, B, C and E identify horizons. Most soils have three major horizons A, B, and C. The hard bedrock, which is not soil, uses the letter R. ´ Surface Horizon (A) – composed of mineral matter mixed with dark organic humus. ´ Subsoil (B) – is the accumulated clay and other nutrients from the layer above it. ´ Substratum (C) – composed of partially altered parent material. ´ Organic Horizon (O) – composed of loose or partly decayed organic matter. ´ E- characterized by significant loss of minerals (eluviation) and leaching. ´ Surface Horizon (A) – composed of mineral matter mixed with dark organic humus. ´ Subsoil (B) – is the accumulated clay and other nutrients from the layer above it. ´ Substratum (C) – composed of partially altered parent material. ´ Organic Horizon (O) – composed of loose or partly decayed organic matter. ´ E- characterized by significant loss of minerals (eluviation) and leaching. ´ The amount of Nitrogen, Phosphorus, and Potassium in the soils is important for plant growth. A simple and easy way for farmers to quickly identify the macro and micronutrient deficiency in the soil through the use of Rapid Soil Test kit (RST) which is available from Bureau of Soils and Water Management of the Department of Agriculture. ´ Nitrogen - is one of the main chemical elements required for plant growth and photosynthesis. ´ Phosphorus - Phosphorus is vital for strong growth. Insufficient phosphorus in the soil will cause stunted, spindly crops. ´ Potassium - the third of three elements in healthy soil nutrition, can greatly increase crop yields. It aids in water absorption and retention, also encourages strong roots, sturdy stems, and healthy, full grown crops that have longer shelf life. ´ Soil is not a dirt, it’s a resource. It’s a main component of land resources, agriculture, and ecological sustainability. It also provides food and foundation for shelter. Soil provides us with the ff. services. ´ Arable land for Agriculture – plowable lands which could be used to grow crops. ´ Regulating Water and Filtering Potential Pollutants – water absorption and storing groundwater. Minerals and microbes in the soil filter, degrade, immobilize, and detoxify organic and inorganic materials. ´ Nutrient Cycling – Carbon, Nitrogen, Phosphorus, and other essential nutrients are stored, transformed, and cycled in the soil. ´ Foundation and Support – provides base for plant roots, foundation and support for human shelter and structures such as houses and roads. ´ Mineral Deposits – soils are mined for their mineral content like iron, nickel, or aluminum. These soils are called laterites. ACTIVITY: Focus Group Discussion In what ways Why is there a How can you can humans need to protect help conserve cause damage and conserve and protect to soil? soil resources? soil? ´ FARMING ´ Use of fertilizers ´ Overgrazing ´ CONSTRUCTION AND DEVELOPMENT ´ Soil Digging ´ MINING ´ Strip and Open Pit mining ´ Sulfide Reacts with Water à Degrades soil quality ´ WASTE DISPOSAL ´ Contamination ´ URBANIZATION – has led to the conversion of land to urban centers which are generally characterized concrete structures, roads, and pavements. These concrete structures represent a significant loss of soil, particularly because this loss becomes more or less permanent as soil is sealed with concrete. According to UN FAO or the Food and Agriculture Organization of the United Nations, 33% of the global soil is moderately to highly degraded through erosion, salinization, compaction, acidification, chemical pollution, and nutrient depletion which hamper soil functions and limit food production,  What are some ways to Conserve and Protect the Soil? Ways to Conserve and Protect Soil ´ Agriculture ´ Conservation Tillage ´ Terracing ´ Contour Farming Ways to Conserve and Protect Soil ´ Home ´ Make surface penetrable ´ Rain Garden ´ Water Collection (Drum) Ways to Conserve and Protect Soil Community Plant Windbreaks Rejuvenate Wetlands Restore forest Cover Proper Waste Disposal and Management Monitor Grazing