The content of available phosphorus in soil is often an important indicator to judge the soil fertility. It reflects the ability of the soil to supply phosphorus. Understanding the content of available phosphorus in the soil is of great significance for guiding the application of phosphate fertilizer.
Since the southern part of China is acidic soil, and the north is alkaline alkaline calcareous soil, the method for determining effective phosphorus is different, and the standard is naturally different. The standard (mg/kg) of available phosphorus (P) in acidic soils is: 0 to 15 is low; 16 to 30 is medium; >30 is high. The standard (mg/kg) of available phosphorus (P) in calcareous soil is: <6 is low; 6-10 is medium; >10 is high. When the soil available phosphorus content is low, it indicates that the soil is deficient in phosphorus or severely deficient in phosphorus, and the application of phosphate fertilizer has obvious or extremely obvious effect; when the soil available phosphorus is medium, it indicates that the application of phosphate fertilizer has certain effect; when the soil has high effective phosphorus content At the time, it indicates that the soil is rich in phosphorus, and the effect of applying phosphate fertilizer is often not obvious. However, for high-yield fields, although the soil available phosphorus content is high, the principle of nutrient balance should also be considered, so proper application of a small amount of phosphate fertilizer is also necessary.
a:
1 The content of available phosphorus in soil is obviously affected by the application of phosphate fertilizer. With the application of a large amount of phosphate fertilizer every year, the soil available phosphorus content will gradually increase. Therefore, the amount of phosphate fertilizer should be appropriately adjusted as the soil available phosphorus content changes.
2 Practice has proved that the combined application of nitrogen and phosphorus is conducive to crop yield increase. It can be seen that it is wrong to apply only phosphate fertilizer or partial application of nitrogen fertilizer. The concept of nutrient balance should be established.
Since the southern part of China is acidic soil, and the north is alkaline alkaline calcareous soil, the method for determining effective phosphorus is different, and the standard is naturally different. The standard (mg/kg) of available phosphorus (P) in acidic soils is: 0 to 15 is low; 16 to 30 is medium; >30 is high. The standard (mg/kg) of available phosphorus (P) in calcareous soil is: <6 is low; 6-10 is medium; >10 is high. When the soil available phosphorus content is low, it indicates that the soil is deficient in phosphorus or severely deficient in phosphorus, and the application of phosphate fertilizer has obvious or extremely obvious effect; when the soil available phosphorus is medium, it indicates that the application of phosphate fertilizer has certain effect; when the soil has high effective phosphorus content At the time, it indicates that the soil is rich in phosphorus, and the effect of applying phosphate fertilizer is often not obvious. However, for high-yield fields, although the soil available phosphorus content is high, the principle of nutrient balance should also be considered, so proper application of a small amount of phosphate fertilizer is also necessary.
a:
1 The content of available phosphorus in soil is obviously affected by the application of phosphate fertilizer. With the application of a large amount of phosphate fertilizer every year, the soil available phosphorus content will gradually increase. Therefore, the amount of phosphate fertilizer should be appropriately adjusted as the soil available phosphorus content changes.
2 Practice has proved that the combined application of nitrogen and phosphorus is conducive to crop yield increase. It can be seen that it is wrong to apply only phosphate fertilizer or partial application of nitrogen fertilizer. The concept of nutrient balance should be established.
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