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The nitric acid flush of meltwater may cause a sharp, short term, decrease in the drainage water pH entering groundwater and surface waters. [7] The decrease in pH can solubilize Al 3+ that is toxic to fish, [ 8 ] especially newly-hatched fry with immature gill systems through which they pass large volumes of water to obtain O 2 for respiration.
The rhizosphere is the thin area of soil immediately surrounding the root system. It is a densely populated area in which the roots compete with invading root systems of neighboring plant species for space, water, and mineral nutrients as well as form positive and negative relationships with soil-borne microorganisms such as bacteria, fungi and insects.
Soil gases (soil atmosphere [1]) are the gases found in the air space between soil components. The spaces between the solid soil particles, if they do not contain water, are filled with air. The primary soil gases are nitrogen, carbon dioxide and oxygen. [2] Oxygen is critical because it allows for respiration of both plant roots and soil ...
Nutrients in the soil are taken up by the plant through its roots, and in particular its root hairs.To be taken up by a plant, a nutrient element must be located near the root surface; however, the supply of nutrients in contact with the root is rapidly depleted within a distance of ca. 2 mm. [14] There are three basic mechanisms whereby nutrient ions dissolved in the soil solution are brought ...
Eutrophication, a decline in oxygen content of water, of aquatic systems can cause the death of fish and other marine species. Finally, leaching of NO 3 from acidic sources can increase the loss of calcium and other soil nutrients, thereby reducing an ecosystem's productivity. [2]
Soil chemistry is the study of the chemical characteristics of soil.Soil chemistry is affected by mineral composition, organic matter and environmental factors. In the early 1870s a consulting chemist to the Royal Agricultural Society in England, named J. Thomas Way, performed many experiments on how soils exchange ions, and is considered the father of soil chemistry. [1]
As a result, the clay disperses and settles into voids between peds, causing those to close. In this way the open structure of the soil is destroyed and the soil is made impenetrable to air and water. [41] Such sodic soil (also called haline soil) tends to form columnar peds near the surface. [42]
It is of use in calculating the amount of lime needed to neutralise an acid soil (lime requirement). The amount of lime needed to neutralize a soil must take account of the amount of acid forming ions on the colloids (exchangeable acidity), not just those in the soil water solution (free acidity). [131]