EVERYDAY SCIENCE

Detailed explanation-1: -Physically, organic matter influences soil structure and all associated properties. Chemically, soil organic matter affects the cation exchange capacity and the capacity for buffering changes in soil pH. Biologically, organic matter acts as the nutrient and energy supply for microbial biomass and higher plants.

Detailed explanation-2: -CHEMICAL: Soil organic matter significantly improves the soil’s capacity to store and supply essential nutrients (such as nitrogen, phosphorus, potassium, calcium and magnesium), and to retain toxic elements. It allows the soil to cope with changes in soil acidity, and helps soil minerals to decompose faster.

Detailed explanation-3: -environmental issues Loss of soil organic carbon content can limit the soil’s ability to provide nutrients for sustainable plant production. This may lead to lower yields and affect food security. Less organic carbon also means less food for the living organisms present in the soil, thus reducing soil biodiversity.

Detailed explanation-4: -Factors influencing the cation exchange capacity of soils Factors influencing the CEC include the soil type, the soil pH and the soil organic matter content. Soils are made up of sand, organic matter, silt and clay particles.

Detailed explanation-5: -Clay and organic matter have negative charges and hold cations. In general, soils with larger amounts of clay or organic matter have more negative charges and therefore a higher CEC than ones with lower amounts. You can think of this as a stronger magnet holding more paperclips.