NEET BIOLOGY

Detailed explanation-1: -Dark brown or black color in soil indicates that the soil has a high organic matter content. Wet soil will appear darker than dry soil. However, the presence of water also affects soil color by affecting the oxidation rate. Soil that has a high water content will have less air in the soil, specifically less oxygen.

Detailed explanation-2: -Humus is dark, organic material that forms in soil when plant and animal matter decays.

Detailed explanation-3: -Humus is the stabilized particles of highly decomposed organic matter. Deep brown in color, humus forms over several years and provides nutrients and soil structure for plant growth. Humus should comprise about 50 percent of garden soil for optimal growth.

Detailed explanation-4: -The A horizon is usually darker than other horizons because of the organic materials. moisture. It generally has a lighter colour and less biological activity than the A horizon. Texture may be heavier than the A horizon too.