Study On The Migration And Transformation And Effects Of Soil-micro Aggregates After PAM Application In Red Soil Tea Garden

In recent years, the tea industry in Fujian Province have a rapid development, but with the irrational exploitation and utilization, soil erosion is becoming more and more serious, has seriously hindered the sustainable development of tea industry, which is a severe problem faced by Fujian province.Polyacrylamide (PAM) as a new type of soil and water conservation measures, play an important role in soil and water loss control, the study of PAM in the tea garden of soil suitability is less, and the environmental behavior of PAM in tea garden soil is more a lack of study.Therefore, it has an important significance in study on the migration and transformation as well as the impact on Soil Micro aggregate composition and stability after the application of PAM in the tea garden.The test given in two locations,design of PAM application rates were A six concentration(0, 1.5,3,4.5,6,7.5g/m2) and B six concentration (0,2,4,6,8,10g/m2).In May, July and October three months to collect soil samples to analyze impact on physical and chemical properties of the soil and the migration and transformation as well as the impact on Soil Micro aggregate composition and stability under the condition of different concentrations of PAM t in the A and B two districts.The results show that:(1) Within a short period of time,the bulk density and organic matter will not change significantly after the application of PAM in the soil of tea garden; PAM can improve soil structure, is conducive to absorb and maintain the soil nutrient better. With the passage of time, the available nutrient content in A, B districts is also a corresponding drop with the slow migration of PAM.(2) With the increase of concentration of PAM in experimental plots, the content of PAM in soil layer of experimental plots also increased; with the passage of time, the content of PAM in soil layer of experimental plots decreased gradually, there will be a slow process of loss; the content of three samples measured by cell PAM experimental plots increased after a lapse of three times with the increase of the concentration of the test area. Most of the PAM residue in the soil layer of 0-20cm and the degradation rate of PAM is very slow, the higher the concentration of PMA,the longer residue in soil layers,the more difficult to degradation; the lower the concentration of PMA, the PMA residue in the soil in a relatively short time, relatively easy to degrade.(3) The advantages of particle size of soil micro aggregates were 50～250μm and 10～ 500μm with different concentrations of PAM in the 0-20cm. The bigger size composition of soil aggregates,the faster effect of different soil particle content of PAM treatment, the smaller size composition of soil aggregates,the slower effect. Overall, PAM measures can be used to improve the stability of soil aggregates.