Soil Fertility Evaluation And Its Application Study In Huanyin Zone,Huanan City

In the population-resources-environmental systems, cultivated land resources are in the basic position and they are the basic support of the national economy and the people’s livelihood. Land use condition and its changes not only affect the development of regional economy, but also bring threat to the ecological environment. It is very important to analyze and master the detailed information timely and accurately on cultivated land resources, and ensure them sufficiently in quantity and quality. They are the foundation of scientific management and effective utilization of cultivated land resources. Meanwhile, they are taken as an important basis to make a detailed plan for agriculture and the national economic. In this paper, the quality of arable land resources management information system was built by GIS technology in Huaiyin Zone, Huaian City. From that, we selected11evaluation indicators in this zone from the four elements (Site Condition, composition of profile, physical and chemical properties, and soil management).Based on Integrated fertility index (IFI) of the cultivated land, the results showed that, with the cumulative frequency method, the basic cultivated farmland (97.01×104mu) in the whole zone can be divided into4grades. Among it, the IFI of the cultivated land at the first grade was11.48×04mu, accounting for11.83%of total cultivated area. Where, the area at the second, third and fourth grade was57.62×104,21.45×104and6.46×104mu, which accounted for59.39%,22.12%and6.66%of total cultivated area, respectively. In this paper, thematic evaluation, marries well with the needs of production, was conducted in the whole zone. Meanwhile, we studied the utilization of regional cultivated land and guarantee measures in this zone. After statistically analyzing6000soil sample of cultivated land by examing physical and chemical properties, some very important information has been gotten. For example, compared to the second national soil survey, the results indicated that the content of soil nutrient in Huaiyin Zone has the following characteristics:three improvements, three declines and one decrease.With the county’s soil fertility GIS-based evaluation, the dynamics of soil nutrient was analyzed, the assessing system on soil fertility level were rationally defined and applied in agricultural practices. Thereafter, we proposed several measures in practices, such as application of organic fertilizer, carrying out soil testing and formula fertilization, deep ploughing and subsoiling, systematic monitoring of land quality, and so on. It is also important with this evaluation to hold the concrete conditions of soil fertility in this county, ensure the development of agriculture, and realize the agricultural modernization and sustainable development.