Effects Of Vermicompost On The Improvement Of Krasnozem

China is a country with a very poor arable land resources. In the past years the deterioration of arable land has becoming the major obstacle to he sustainable development of agriculture. Vermicompost has been widely used to reclaim waste as it is rich in protein, easy to produce, has no secondary pollution and large pH buffer capacity. Krasnozem region, due to its large area, is one of the regions with high potential for agricultural production in China. To improve the poor Krasnozemsoil will be an important measure to improve agricultural productivity, thus the grain yield, which has great significance in guaranteeing regional food security and the increase of rural incomes.This paper aimed studying the effects of vermicompost use on Krasnozem improvement by determining the physico-chemical properties, the change of microbial and enzyme activities, as well as the effects of vermicompost and Krasnozem mixture on crops.For the experiment, Krasnozem was sampled from Yingtan, Jiangxi. Vermicompost was mixed into soil at the percentage of 0,5,10,15,20 (by weight) respectively. The mixture was incubated and sampled for the detection of physical and chemical properties, as well as nutrient concentrations. After incubation and stabilization, the mixture was used for the growth of pakchoi seedlings.After planting soil physical and chemical properties, nutrient status and soil microbial biomass and enzyme activity were determined to investigated the effects of tillage on improved soil and the influence of vermicompost on Krasnozem. Growth and nutrient uptake of cabbage seedlings were recorded to study the effect of vermicompost application on subsoil improvement and to achieve an optimal ratio of vermicompost use.The main results are as follows:(1)Adding appropriate amount of vermicompost could improve the physical and chemical properties of Krasnozem. The pH of the mixture could be increase to neutralize the acidic soil which is toxic to plants. Vermicompot addition decreased soil bulk density, porosity, while improved water-holding capacity and aeration, providing the roots with a better access to water, fertilizer, and oxygen. The best root growth was observed in the treatment amended with 5% to 10% vermicompost.(2)Nutrient status of Krasnozem was improved by the addition of vermicompost. Higher ratio of vermicompost addition resulted in higher nitrogen and phosphorus content, which could eliminate the problem of phosphorus scarcity in Krasnozem and improve soil fertility and stability, providing a good environment for the growth of crops. It has to be pointed out, vermicompost use might cause osmotic stress due to high electrolyte concentration and increase water pollution load because of the release of high concentration of nitrogen and phosphorus.(3)Tillage improved soil physical and chemical properties, while decrease soil fertility on the other hand,. Therefore, the improved soil for a period of time should be fertilized, in order to achieve sustainable use.(4)Increasing the proportion of vermicompost could increase microbial biomass in the soil. Increasing the proportion of earthworm manure could improve the activity of the enzyme in the mixturewas improved, with the increase of the urease, phosphatase, dehydrogenase activity and catalase activity. Soil biological activity and soil fertility status were accordingly improved. The best improving effect was achieved when adding 10% of earthworm manure.(5)Krasnozem showed low nitrogen fixation while high phosphorus fixation ability. Excess vermicompost may cause eutrophication and water pollution. The ration of vermicompost should be restricted between 5%-10% for safe use.(6)Adding vermicompost increased chlorophyll and carotenoid content of Chinese cabbage, improved leaf photosynthetic capacity and seedling biomass, promoted the growth of root. Excessively high proportion of vermicompost would lead to a nitrate accumulation and nutrient supply imbalance, which inhibited seed germination and seedling growth of Chinese cabbage. Therefore, from non heading Chinese cabbage growth, adding 5%-10% vermicast is recommended.In conclusion, the optimal improving effects were achieved on Krasnozem with the addition of vermicompost at a ratio 5%-10% by weight.