Geochemical Study On The Soil In The Upper Reaches Of Huaihe River, Henan Province

With the development of social economy in our country, soil heavy metals,pesticide residues, fertilizer pollution and sewage irrigation, which affect the qualityof agricultural products, show a spreading trend. Especially after our entering WTO,several developed countries carried out "green barrier" to the agricultural products export of our country, causing huge economical loss to the state, enterprises and farmers, which is not conducive to agricultural efficiency, farmers’income increase,and rural economic development. At present, the environmental background of most and quality in our country is still unknown, so there lacks basic foundations for regional land use planning and industry planning. Therefore, it is urgent to realize scientific agriculture planning, adjust agricultural economic structure, develop agricultural economy, and find out the environmental quality of agro-geology.Based on theory of environment geochemistry, soil geochemistry, agro-geology geochemistry and ecology geochemistry, this thesis carried out geochemical field survey in the study area combining with its practical complexion. According to the geological background, terrain, and soil types, field samples were collected for test.Then the data from sample test were used, by mathematical statistics and GIS technology, to synthetically study the geochemical characteristics of soil in Huaihe river upstream region of Henan province. The results of soil fertility assessment and ecological effect, was used to gradate land quality on geochemistry, this thesis adjusted land use structure and industry structure, in order to provide scientific support for new rural construction and land’s social-economical benefit increase.This thesis got main results as follows:1、Compared with the national soil element content, benchmark of that is generally low in upstream of huaihe river, Henan province. CaO, S, Br and Hg content is less than half of the national content. N, Mo and Corg content is slightly higher than half of that. Cl, I and Sr content is low, only F, Y, Sn, Be, Ni, and B content is far higher than the national. Basic value of Southern soil in the study area directly influenced by soil parent rock, the performance characteristics are associated with bedrock area around the main ore layers, reflecting the proximal soil geochemical characteristics of the parent material. Abnormal distribution of mercury and gold in the surrounding area and local planar pollution formation reflect the impact of human production, livelihood on the soil environment.2、Overall, the plains soil geochemical quality is good in upstream of Huaihe river, Henan province. Poisonous and harmful elements are mainly distributed in areas which are south to XinCaiXian county, west to huai bin county and north to xixian county, accounted for7.2%of the study area. Vast soil in north of the study area is relatively safe.3、PH values of the soil in upstream of huaihe river, henan province are among5.0～ 8.37, weakly acidic to alkaline from south to north; The content of organic carbon is among0.32～2.32%, high content areas mainly distributed in XiangCheng and ShangShui, south of zhoukou city and luohe west to zhoukou city.4、Soil fertility quality evaluation research shows that the plain soil in upstream huaihe river, Henan province, is fertile, moderate fertility land accounted for above71%. Overall, northern basin for the Yellow River in soil fertility status is better than southern basin of the huaihe river, especially the alluvial plain. Limited by many factors such as geology and geography, beneficial nutrient elements in huanghuai plain economic zone are distributed very unequally. It shows that in the Yellow River basin calcium, magnesium and phosphorus is rich, potassium, molybdenum is enough, copper, zinc, iron, boron and nitrogen is deficient, in the huai river basin nitrogen, boron is rich, phosphorus, potassium, calcium, magnesium, sulfur, zinc, molybdenum and other elements is deficient. In general, land quality in Upstream of Huaihe river is fertile.5、Overall soil environment quality is good in upstream of Huaihe river, Henan province, and more than71%of the soil quality grade is good, these areas can be further detailed researched on ecological geochemical assessment, then different types of pollution-free and green-food production bases can be constructed.