Research On Bentonite-bacteria Residue Composite Materials In Sandy Soil Nutrient Release

China is accelerating the development of agricultural modernization. Soil fertilizer usage is also increasing at the same time. However it reduces the inorganic fertilizer utilization rate. This is not only no effect on crop yield increase, but also has an impact on water and soil environment. On the other hand, because of bentonite and mushroom residue’s excellent physical and chemical properties, they have been widely applied in improving soil structure, and the study of improving the quality of the soil now.This study used bentonite and mushroom residue in accordance with the quality propotion 1:1.5; 1:2.0; 1:2.5; to make of composite materials. The composite materials were used on sandy soil to cultivate Belgian azaleas in this pot experiment. In sandy soil were added 1.00 kg,1.50 kg,2.00 kg and different ratio of composite materials. After that, analysised impact on sandy soil physical and chemical properties and nutrient content every month, and the Belgian azaleas’s situation and leaves’s nutrient content, to discuss the bentonite and mushroom residue composite material’s nrient release rule and composite material’s best propotion. Experiment results showed that:(1) Bentonite-mushroom residue composite materials can effectively improve sandy soil physical and chemical properties. Part of treatments’s sandy soil pH values were above 7.00. All the treatments sour alkali were slightly down in late January. Meet the requirements of the Belgian azaleas in acidic sandy soil conditions or requirements. The effect was more obvious as time goes by. All the treatments’s pH value range was between 6.14-6.31 at the end of the experiment. Composite materials can reduce the effect of sandy soil bulk density. Bulk density as the composites decreases with the increasing of the amount. Sandy soil bulk density reduced decrease with bentonite and mushroom residue’s proportion increasing. T10 treatment’s change was the most. From December to May, Bulk density by a month fell 3.18%,5.10%,5.10%,3.90%,5.84%, The average bulk dropped 4.62% a month. Before and after the experiment density dropped 6.50% in total. Sandy soil water content are improved greatly. T10 treatment was the best effect. Cmpared with CK, T10 treatment increased 73.14% on the average of every month. Change law and with the increment of composite material applied into, mushroom residue intake increased, sandy soil water content showed a trend of increase.(2) Bentonite-mushroom residue composite materials can significantly improve of nitrogen, phosphorus, potassium content in the sandy soil. Improving the effect of sandy soil total nitrogen and total potassium content was obvious. T8 treatment was the best effect. Cmpared with CK, T8 treatment increased total nitrogen content 19.87%, total potassium content 19.00%. All of the treatments sandy soil’s total phosphorus content had greatly increased in December. Cmpared with CK, the treatments increased by 23.32%-23.32%, and declined month by month. The differences between the treatments were not obvious from April to May. Bentonite-mushroom residue composite materials can significantly improve of the sandy soil available nutrient content too. Improving the effect of available potassium was best. They can improve the available potassium content 0.87-3.70 times, and with the increase of applying bentonite content increased. Sandy soil available nitrogen and available phosphorus content in the application of composite materials were also improved. The abilities of the composite material to improve the available nutrient content were in turn:available potassium, available nitrogen and available phosphorus. T9 treatment was the best effect. The available potassium, available nitrogen and available phosphorus content by T9 treatment compared with CK improved 370.00%,141.00%,16.08%.(3) Bentonite-mushroom residue composite materials can effectively improve the Belgian azaleas’s leaves nutrient content. The abilities of the composite material to improve the leaves tatal nutrient content were in turn:nitrogen, potassium and phosphorus. Leaves total nitrogen and total potassium content not only compared with CK were increased, but also the content was a trend of increasing month by month. T10 treatment was the best effect. The leaves nitrogen, phosphorus and potassium content by T10 treatment compared with CK improved:24.01%,41.26%,32.65%. Although the leaves total phosphorus content compared with CK was increased, the content decreasing month by month. Composite materials can effectively control the Belgian azaleas’s high-diameter ratio between 43.19-58.32. T10 treatment was the best effect. Composite materials also can effectively improve the Belgian azaleas’s number of flower buds and flowering. T7 and T8 treatments can extend the Belgian azaleas flowering phase.(4) Comprehensive consideration that Bentonite-mushroom residue composite materials’s effects on the sandy soil physical and chemical properties, nutrient content, the Belgian azaleas’s growth and leaves nutrient content etc. Come to the conclusion:T8 treatment, application 2.00 kg proportion of 1:1.5 the bentonite-mushroom residue composite material per 10.00 kg sandy soil is the best treatment.