Causes and Principles of Soil Compaction
Soil compaction refers to the phenomenon that the soil surface is damaged by the external cause, the soil structure is dispersed, and the fertilizer is absorbed by the soil after drying. It is a problem often encountered in agricultural production.
The aggregate structure of soil is an important index of soil fertility, and the destruction of soil aggregate structure leads to the decrease of soil water holding capacity, fertility conservation and permeability, resulting in soil compaction;
The content of organic matter is an important index of soil fertility and aggregate structure, and the reduction of organic matter leads to soil compaction.
Long term use of chemical fertilizer, humus can not be timely supplement, not only will cause soil compaction, may also crack. The reason why chemical fertilizer causes soil compaction is that only cations or anions are the elements needed by plants, and plants choose to absorb useful ions unilaterally, resulting in acidification or salinization of the soil.
Soil organic matter is an important component of soil aggregate structure, and the decomposition of soil organic matter is realized by microbial activity. To the soil in excess of nitrogen fertilizer, microbial nitrogen supply increased 1, the corresponding consumption of carbon increased 25, the consumption of carbon sources on soil organic matter, organic matter content is low, influence microbial activity, thus affecting the formation of soil aggregate structure, lead to soil compaction.
Cation in soil with calcium and magnesium ions 2 valence mainly to the soil in excess of P fertilizer, combined with calcium and magnesium ions such as phosphate ions in soil and the formation of insoluble phosphate, that is a waste of fertilizer, but also damage the soil aggregate structure, soil compaction.
To the soil in excess fertilizer potassium, potassium replacement of potassium in the particularly strong, can form a replacement out of soil aggregate structure of multivalent cations, and potassium ion is not monovalent key bridge, the bridge of soil aggregate structure was destroyed, also destroyed the aggregate structure, resulting in soil compaction.
The hazards of soil compaction and why
Soil compaction under the condition of hypoxia caused the decrease of root activity, not the normal development of respiratory, plant root cells decreased, and nitrogen nutrition and the ion state, to absorb the energy generated by the consumption of cell metabolism, decreased respiration, the insufficient energy supply, affect nutrient absorption.
Soil compaction can also cause deficiency. The deficiency in soil is sometimes not necessarily lack this element, but because of soil compaction, soil pH is not suitable, or is caused by soil water supply imbalance in a series of problems such as the root absorption capacity decrease.
The principle of breaking the soil
Organic fertilizer or microbial fertilizer to the soil, will gradually restore the beneficial microbial communities in soil microbial exudates dissolved phosphate in soil, phosphorus will be released at the same time, will also release potassium and trace elements to form cation, key bridge restoration aggregate structure, eliminate the soil compaction.
