Review of application of geochemistry in agriculture

Abstract

There is a close relationship between geochemistry and agriculture. The soil, water and atmosphere provide nutrients for plant growth, so the growth and development of plants are affected by the geochemical characteristics of soil, water, and atmospheric sediments. There is a Chinese proverb that a plant grows orange on south of the Huaihe River and fen on north of the Huai River. Therefore, it is not only sunshine, temperature, air, water, but also soil fertility that affects the growth of plants. Soil fertility includes trace elements and rare earth elements. There are also some elements in the soil that have a special role in human health[2]. Similarly, the lack and excess of elements in the soil can cause corresponding endemic diseases. In recent years, fertilization and spraying of pesticides in agricultural activities and the discharge of waste water, slag and exhaust gas from industry have had a great impact on the soil. The rapid increase in the content of organic chemicals and heavy metals in the soil will be absorbed by plants into the food chain, which will affect human health. It is very meaningful for land and resources management, agricultural industrial restructuring, and high-quality agricultural planning to investigate the geochemical characteristics of soil, water and atmosphere. Because the absorption of chemical elements in plant growth comes not only from the soil, but also from the supply of irrigation water and atmospheric dust, land quality geochemical survey collects soil, irrigation water, atmospheric dry and wet sediments and agricultural products. The investigation contains elements that affect plant growth and elements that affect life and health. By analyzing the elements in soil, irrigation water, and atmospheric sediments, the relationship between them and the growth of crops and the content of elements in agricultural products is obtained. Then carry out land quality geochemical evaluation, and divide areas suitable for crop growth and areas not suitable for plant growth which contaminated with heavy metals, excessive pesticide residues, organic chemicals, etc. The geochemical classification of land quality is obtained. According to grading investigate the geological factors, environmental factors and human factors that affect land quality, grasp the geochemical reality and ecological problems caused by human activities, and predict the trend of development. Based on the understanding of planting structure, land use status, etc., the we looks for suitable planning suggestions for local development. (1)In terms of land and resources management[3], it includes providing evidence for the classification and grading of arable land, land planning, basic farmland demarcation, land consolidation, land stripping, and balance of arable land. Through the land quality geochemistry investigation, according to the distribution of land quality geochemistry, combined with soil type and land use, the cultivated land classification. To guide the layout of construction land and basic farmland in the light of the current land use situation and recent planning. In terms of land consolidation, it can provide basis for land consolidation and improve ecological conditions according to the land quality geochemistry level. (2) In the adjustment of agricultural industry structure, it provides scientific basis for the development and utilization of high-quality land resources and then helps local economic development. Through investigation, it is found that the land resources such as selenium, strontium, zinc and other special land resources and pollution-free land[4], on which we can develop special agricultural products and green agricultural products, thereby increasing the additional economic value of agricultural products and improving market competitiveness.