OBJECTIVE FORESTRY

Detailed explanation-1: -In general, soil contains 40-45% inorganic matter, 5% organic matter, 25% water, and 25% air. In order to sustain plant life, the proper mix of air, water, minerals, and organic material is required.

Detailed explanation-2: -The typical soil consists of approximately 45% mineral, 5% organic matter, 20-30% water, and 20-30% air. These percentages are only generalizations at best. In reality, the soil is very complex and dynamic.

Detailed explanation-3: -Soil is an organism that breathes in and out. Pores not filled with water are filled with soil air: a mixture of 79% nitrogen, less than 20.6% oxygen, and generally more than 0.2% carbon dioxide (CO2)1. The air in soil is in constant exchange with the atmosphere.

Detailed explanation-4: -An ideal soil would be made up of 45% minerals (sand, clay, silt), 5 % organic (plant and animal) material, 25% air and 25% water.

Detailed explanation-5: -Soil-Air Composition Thus, the relative amount of void or pore space in the soil varies between approximately 30 and 60%. The soil pores or voids can be filled with either air or water. Therefore the soil-air content or air-filled porosity can vary between approximately 30 and 60%.