Soil Protection - Formation and Consumption of Soil Organic Oxygen

I. Formation of organic oxygen in the soil

Organic nutrients in the soil refer to all the organic substances of the plant from the soil. They can be divided into organic matter that basically keeps the original state of the plant and animal remnants, and decomposes the rot that is not recognized in the original residue state. There are three types of humic organic colloids synthesized under the action of microorganisms and often combined with organic colloids and microorganisms. The three types are the different stages of decomposition and transformation of animal and plant residues, but the main components are carbohydrates, nitrogen compounds and lignin. Under natural conditions, the vegetation, deciduous roots and roots of trees, grasses and other plants provide large amounts of organic debris each year. In addition, a large number of plant residues in the farmland remain in the soil. These substances are decomposed and converted into various nutrients by the microorganisms in the soil and stored in the soil to form soil organic matter. Soil organic matter is continuously decomposed due to the activity of microorganisms, and the decomposition rate is much faster than that of rock minerals, so it is very unstable. The amount of soil organic matter directly affects the supply of soil nutrients.

Second, the consumption of organic oxygen in the soil

The depletion of soil nutrients mainly refers to the nutrient that the crop absorbs from the soil each year, the nutrients that are leached with the infiltrating water in the soil, and the nitrogen nutrients that are volatilized in the form of gas during the process of nutrient conversion. In addition, the soil erosion caused by soil erosion on the soil surface, It also causes loss of various soil nutrients. The soil contains a large number of microorganisms. These microorganisms are numerous in nature. They break down the organic matter of the soil and extract the energy and nutrients they need for growth and reproduction. At the same time, the potential nutrients combined with organic matter and difficult to use by plants are turned into effective nutrients. For the growth and development of crops, the total amount of nutrients in the soil will decrease. Most of the nutrients needed for crop growth and development are drawn from the soil solution. Precipitation or irrigation increases the amount of water in the soil and can meet the needs of crops for water and nutrients. However, the increase of soil moisture also accelerates the diffusion of soil solution, so that the nutrients are leached or eluted from the root layer of the crop to the deep layer of the soil, resulting in a reduction of the nutrient content in the effective space of the crop rhizosphere. The extent of leaching of nutrients is closely related to the soil texture. The clay in the clay field has strong adsorption and retention for the segregants, and the leaching loss of nutrients is relatively small, while the sand has weak adsorption capacity, and the nutrients easily leaching into the soil with water. Deep. The consumption of soil nutrients greatly changes the ratio of nutrient partitioning and content in the effective rhizosphere of crops. Some nutrients cannot meet the nutritional requirements of crops and affect the normal growth and development of crops. In this case, artificial fertilization must be performed to supplement nutrients to meet the normal growth and development of the crop.