Investigation And Evaluation On Cultivated Land Fertility Of HuaYuan County

Huayuan County, the west frontier of Hunan Province, bordering on Guizhou and Chongqing Province, has been known as the south-west portal of Hunan. From 2009, Huayuan County has resorted to many ways such as open country field investigation and sampling, indoor analysis, GIS, GPS and computers to conduct a detailed study and analysis of the soil quality of the farmland. The results are mainly as follows:(1)the county level index of evaluating farming soil fertility is settled by experts according to the requests for the process evaluating farmland by Technical Specification for the National Farmland Evaluation, using farmland reserving planning graph and soil picture overlapping patch as a evaluating unit, dependent on the national farmland investigation evaluating index graph. Application of hierarchy analysis process to determine the index weighting, standardization of indicators by expert experience, by summation method to calculate individual evaluation units of the synthetic fertility index, the experts complete the amount of farmland evaluation, preliminarily pioneering the application of the statutes of the cultivated land fertility survey and evaluation of effective work methods and technological processes.(2) Huayuan County farmland values acidic soil, pH value in the range between 5.57-7.21. soil bulk density is more between 1.121-1.32. The organic content is low, organic matter amplitude between 18.7-39.97g|kg. Huayuan nitrogen varied from 134.9-319.9mg/kg; The Huayuan County effective phosphorus content is low, the range of variation is 3.83-12.96mg/kg. The Huayuan County soil fast-acting potassium content undulates between 76-213.2mg/kg, Slowly available potassium content is very low, ranging between 39.9-123.4mg/kg,50-100mg/kg of a light gray sand and mud residue Tianhuang shallow flat rock across the gray-green mud Wong in 27 soil types.In addition, slow soil effective phosphorus potassium phosphate fertilizer applied is low, it is necessary to pay attention to the remaining indicators and potash. The rest are very much in line with rice cultivation. Via the fertilizer, organic fertilizer control, increased use inorganic nitrogen fertilizer, phosphate potash fertilizer, we can get a balance between production.(3) According to the results of the evaluation of fertility of arable land, Huayuan County has 35.69 million mu cultivated land, and six grades of 1-6. In accordance with the national high, medium, and low-yield land demarcation yields, high yield indicators yields> 800 kg/mu, including Level 1 and Level 2 arable land area, from 52,700 acres, accounting 14.76% of the total area.The middle field yields 600-800kg/ acre, including 3,4 arable land, an area of 12.73 million mu, accounting for 35.66%. In low-yielding fields yield<600kg/mu, including five and six arable land, an area of 17.69 million mu, accounting for 49.58%.Through various levels to evaluate factors and fertility factors analyzed we find Huayuan County land constraints at all levels of fertility include phosphorus, slow-release potassium, topsoil thickness and soil texture. we can see, these three factors are Farmland a major limiting factor, followed by low-level ground at all, the ability of irrigation and drainage capacity is also an important limiting factor. Therefore, the Huayuan County has to substantially improve potash, heavily apply phosphate fertilizer, increase the layer thickness,improve the soil texture and strengthen the irrigation and drainage facilities as.