Soil testing has now developed into a relatively independent edge science (still a branch of soil science). It has its unique scientific theory foundation and necessary basic technical work. Soil testing uses modern instruments such as soil testers to make soil testing easier and more accurate.
For example, a lot of related research and verification studies must be done to develop the land test. In the past, China has done very little on these studies. At present, some units directly use foreign extraction methods and nutrient grading standards; others simply propose an extraction method through simple tests. There is no theoretical basis for soil chemistry and there is no factual basis for related research or research. Such an extraction method certainly cannot reflect the actual situation of soil nutrient fertility.
Scientists believe that soil surveys should be used to solve soil classification problems and the major nature of large-area soils. It can be used as the main basis for agriculture, suitable for forestry, suitable for harvesting, or both; it is also the main basis for the design decisions of farming methods, irrigation methods, and farm implements. Because these aspects of the soil are often relatively stable and change slowly, Therefore, the soil survey can be conducted once in ten years or more. The analysis project should be based on the nature of the soil itself without necessarily including the nutrient content determination.
On the other hand, soil nutrient content is dynamic and often varies. The more intensive agricultural production, the higher the demand for crop yield, the faster the change in soil nutrient content. It does not matter if you measure it once in ten years. The agricultural developed countries re-determine the nutrient content of specific fields every year or even every ripening to use as a basis for the fertilization plan. Therefore, it is not possible to include nutrient content measurements in large-scale soil surveys.
Based on this, we believe that it is advisable to properly divide soil surveys and soil tests in our country's soil surveys and establish two professional committees to work together. At a minimum, analytical and measurement professional groups should be established at the national level, and professional teams at the provincial level should be established so that soil analysis and determination work can play a greater role in the census of the upper reaches.
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