The prerequisite for the scientific utilization of land resources in China is to analyze and judge the basic conditions of the soil first. The development of modern science and technology makes people increasingly use the soil analyzers and other scientific precision instruments to analyze and test the soil. Then the soil analysis What exactly is the investigation?
(1) Soil survey, classification and mapping (including some analysis projects for soil classification services), which provide basis for large-area land use and agricultural area planning; (2) Determination of soil nutrient (or "soil test") This part of the work is entirely based on the economic and rational fertilization plan. It involves a smaller area of ​​soil and more detailed work.
At the international level, the above two departments have developed two separate branches of soil science. In our country's soil survey, we mixed the above two aspects of work and hoped that "it will be a success." This desire is good, but some problems have occurred in the actual work process. The focus of the problem is on how to analyze and measure soil samples. We will discuss with you some of the issues we have come across.
Xu Ba, a professor of soil chemistry at the Rutger University in the United States, first raised this issue with the author. He said why it is incomprehensible to use soil fertility testing as the main analysis item in China's soil survey. This problem is what we ourselves have failed to understand. Now we put forward our own preliminary views.
Vice Premier Li Xiannian made the following instructions for the purpose of the census of the soil. “Depending on the soil conditions and other natural conditions, whether to develop agriculture or forestry, animal husbandry, or both; determine what crops need to be cultivated and what fertilizers they need. Irrigation methods, farming methods and what agricultural machinery."
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