Study On Soil Acidification And Influencing Factors In The Chengdu Plain

The soil acidification caused the soil physical property to worsen, nutrient supply of soil changed, activated soil the heavy metal and the virulent element, caused the soil microbiology condition environment and the microorganism area changed simultaneously, then influenced crops' normal growth, became one of main barrier factors to enhance farming productivity of soil. Our country's research mainly focused on efflorescent deeper soil, but to the shallower region which influenced by some cultivation management and environment, the acidified question researched less. The Chengdu plain was our country's important grain and oil production base. In recent years the mustard family crops' root swelled sickness phenomenon was common in this region, the phenomenon of soil acidified highlighted day after day. But it lacked thoroughly and systematic research. In order to clarify the mechanism of soil acidification, prevented the soil further acidified effectively, realized soil resources sustainable use in the Chengdu plain, this research had analyzed the acidified characteristic, the influence factors and the acidified risk of Chengdu plain center.This research took Chengdu plain center as an object. With the help of the global positioning system GPS, located the soil sample's geographical position. Geostatisics and spatial were used to analyze the spatial distribution of soil acid-damage capacity. At the same time, analyzed the facors which made soil acidification caused by new producting condition and environment. Combined with the findings of Helyar, quantified the acid which caused by reaping of crops. Meanwhile based on the research foundation which made by Australian scholar Ridley and so on, has established the relationship between soil acidification rate and soil pH buffer capacity, soil basic properties, with the aid of ArcGIS, made the risk assessment of acidification tendency in the region. The results as follow :(1) Compared with the second general detailed soil survey, soil acid declined generally during the past two decades. The minimum variety of soil pH was in Guanghan and Deyang, and the soil pH declined about half of one unit, but keeping neutrality. Soil pH declined about one unit in the rest aeras, but the maximum variety was in Chongzhou, of soil pH was soil pH declined about one point eight unit. The soil pH of Dujiangyan and a part of Shuangliu region came down to 5.7, the soil pH of the rest areas were between 6.5-6.0. Exchangeable acidity was low in Chengdu plain, and the exchangeable hydrogen was dominant. The results indicated that the trend of soil acid was obvious, but the acid of soil was not very deep yet.(2) The acidic buffering capacity of soil had reflected the soil resistance acid or alkali ability. Soil acidic buffering curve and acid-damage capacity were one of important targets of...