Study On Change Of Soil Nutrient In Miyi County

In this study,on the basis of study on soil nutrient change,both at home and abroad through detailed data collection and analysis of the miyi county the second soil census,in 1980 to 2009 in 30 years during the farmland productivity evaluation of farmland soil nutrients variation characteristics,the main research results are as follows:The second soil census,in 1980,the miyi county farmland soil total nitrogen and alkaline hydrolysis nitrogen content are mainly medium and the lack of level,accounting for 53.0% of the arable land and 53.0% respectively.Effective phosphorus and available potassium is mainly lack of and below the level,which is lack of effective phosphorus content and level of below 87.69%;Soil available potassium content in lack and under 79.17% level.In 2009,the evaluation of farmland productivity,miyi county farmland soil total nitrogen,alkali solution nitrogen and effective phosphorus content are mainly medium and above level,the proportion of 74.59%,81.18% and 84.30% respectively;Rapidly-available potassium mainly lack of level,the proportion of 65.34%.Compared with the analysis,the average content of soil nutrient in miyi county in 2009 was significantly changed from 1980.The total nitrogen content decreased by 0.9% in 1980.The nitric nitrogen content increased by 20%.The effective phosphorus content increased by 37%.The potassium levels fell by 7%.And degree of abundance of nutrients changed,alkali solution nitrogen levels rose from a rich,phosphorus and potassium from down to a lack of levels,but the content of total nitrogen,effective phosphorus is abundant degree does not change.Between 1980 and 2009,the total nitrogen in shatin,tide and alkali solution,the biggest increase of nitrogen content increased 584.9% and 380%,increase the effective phosphorus content of yellow soil is the largest,the increase rate of 447%,black sand soil available potassium content increase the sharpest,the growth of 495.17%.In addition,the county farmland soil nutrient content between different villages and towns small changes.Conclusion: the nutrient of cultivated land in miyi county has changed greatly in the 30 years from 1980 to 2009,and the soil nutrient has been greatly affected by fertilization,with the increase of nitrogen and phosphorus increased greatly,and the potassium decreased slightly.In particular,the planting of early spring vegetables in the area of 1300 m and the following areas in the study area,the increase in soil nutrient growth was huge,and most of the soil nutrient content increased by more than 100 %.In the future maintenance of cultivated land,it is suggested to use the technique of soil testing to determine crop yield and scientific fertilization.It is recommended that the competent departments of agriculture and environmental protection establish and improve the quality supervision and inspection system of cultivated land and strengthen the supervision and management of cultivated land.