Jan 10, 2025 · Soil, the biologically active, porous medium that has developed in the uppermost layer of Earth’s crust. It is one of the principal substrata of life on Earth, serving as a reservoir of water and nutrients, as a medium for the filtration and breakdown of wastes, and as a participant in the cycling of elements.

Soil is a mixture of minerals and organic material that covers much of Earth’s surface. Minerals are bits of rock, and organic material is the remains of living things that have died. Soil is not as solid as rock. It has many small spaces, called pores, that hold water and air.

Dec 24, 2024 · horizon, a distinct layer of soil, approximately parallel with the land surface, whose properties develop from the combined actions of living organisms and percolating water. Because these actions can vary in their effects with increasing depth, it is often the case that more than one horizon exists beneath the surface of any soil area, at ...

evapotranspiration, Loss of water from the soil both by evaporation from the soil surface and by transpiration from the leaves of the plants growing on it. Factors that affect the rate of evapotranspiration include the amount of solar radiation, atmospheric vapor pressure, temperature, wind, and soil moisture. Evapotranspiration accounts for ...

Jan 10, 2025 · Soils on steep, long slopes are much more susceptible to erosion than those on shallow, short slopes because the steeper slopes accelerate the flow of surface runoff. The development of soil conservation strategies requires knowledge of actual and acceptable rates of …

When water from a rainstorm or a period of snowmelt reaches the ground, some or all of it will infiltrate the soil. The rate of infiltration depends on the intensity of the input, the initial moisture condition of the surface soil layer, and the hydraulic characteristics of the soil.

Runoff, in hydrology, quantity of water discharged in surface streams. Runoff includes not only the waters that travel over the land surface and through channels to reach a stream but also interflow, the water that infiltrates the soil surface and travels by means of gravity toward a stream channel

Jan 10, 2025 · Soil - Structure, Composition, Properties: The grain size of soil particles and the aggregate structures they form affect the ability of a soil to transport and retain water, air, and nutrients.

Jan 10, 2025 · It is transformed and transported through the ecosystem by the water cycle and biological processes. This nutrient enters the biosphere primarily as wet deposition to the soil surface (throughfall), where plants, microbial decomposers, or nitrifiers (microbes that convert ammonium [NH 4 +] to nitrate [NO 3 −]) compete for it. This competition ...

In soil: Soil horizons …surface litter) is termed the A horizon. This is a weathered layer that contains an accumulation of humus (decomposed, dark-coloured, carbon-rich matter) and microbial biomass that is mixed with small-grained minerals to form aggregate structures.