我国土壤地球化学及其在农业生产中的意义

我国土壤地球化学特征受生物，气候，母质，地形及人为作用等因素影响，形成了我国独特的土壤地球化学类型和分布格局。不同地球类型，均有各自的元素丰度。土凶素与植物生长和人体健康的关系取决于土壤中元素的有效部分。

PEDOGEOCHEMISTRY OF CHINA AND ITS SIGNIFICANCE IN AGRICULTURE

Pedogeochemistry in China is affected by the factors such as bio climate, parent material, topography and human activities, forming the various geochemical types, including clastic soils, saline soils, gypsic soils, carbonate soils, siallic soils, ferrallic soils and ferrolysed soils, and the spatial distribution of soil geochemical regions which include saline, carbonate, siallic and ferrallic regions from northwestern to southeastern China. The different pedogeochemical type has its own different element abundance that depends on the spatial distribution of soil types. In the saline soil region, available Na, K, B, F, and Cu in soils are rich, but available P, Zn, Fe, Mn and I are deficient. sixty three percent of the region are deficient in P, 80% in Zn and Mn, and 50% in Fe. In the carbonate soil region, available K and B are still rich, but available Zn, Fe, Mn, Mo, I and Se are deficient. On the basis of statistics, about 60% of the region are deficient in P, and 80% in Zn, Mn, Fe and Mo. In the siallic soil region, deficiency of K, B and F is gradually evident, but the area of deficiency in Zn, Mn, Fe, and I decreases. Thirty two percent of the region is deficient in K, and 47% in P. In the ferrallic soil region, available K, B, Mo and F are lack due to strong leaching, on the contrary, available Zn, Mn, Fe in the region are more sufficient than those in the other regions. The toxic of Fe and Mn in some soils even appears. Fouty six percent of this region is inadequate in P, 60% in K, and 90% in B, Mo and F. In a word, the availability of elements are affected by pH, Eh and fertilizing activity besides the states of elements. On the basis of the soil geochemical distribution and types, rational plantation, application of fertilizer to soil types and rational utilization of soil nutrition will be of great significance in raising the yield and improving the quality of agricultural products. Authors suggest that fertilizers be utilized on the basis of soil geochemical characteristics, types, pH, Eh and special necessity of plants.