Study Of Soil Enzyme Changes Of Saline-alkali Paddy Field And Relationships Between Soil Enzyme Changes And Soil Nutrients In Different Planting Years

Soil enzymes are capable of catalyzing biologically active substances in most soil biochemical reactions and important indicators of soil quality. They are widely used to evaluate the status of the conversion of soil nutrient cycling and the effect of various types of agricultural practices. Planting rice is one of the most effective measures to modify soda saline. Previous studies mostly focus on soil physical and chemical properties to explore the mechanism of planting rice to improve the saline soil, but there is a lack of studying biological properties. In order to improve the study of the mechanism, in this study, through improved rice paddy soda saline soil in different years and different soil depths are collected from Jilin province Qianguo town Taohaotai village Jianbalahamlet in the Songnen southern plain as samples, the unimproved grassland soil as control, using survey sampling combined with laboratory analysis as method, determinating the enzyme activities of catalase, peroxidase, alkaline phosphatase, urease, sucrase and soil nutrient content,analyzing the variation of five kinds of soil enzymes dynamic changes in different planting years and different depths, and the relationships between enzymes and soil nutrients. The main results are as follows:1. With increasing planting years and depths, soil catalase and alkaline phosphatase activities overall tend to decline, peroxidase activity tends to decline in the plough layer and plowpan, but volatility increase regularly in subsoil, urease and sucrase activities tend to rise in plough layer, and there is no regular pattern in the activity of these two enzymes in plowman and subsoil.2. From the view of correlation among enzyme activities, in different years of plough layer, sucrease is significantly positively correlated with urease, the correlation coefficient is 0.905.Catalase is significantly negatively correlated with sucrease and notably negatively correlated with urease. Peroxidase is notably positively correlated with catalase and alkaline phoshatase, and notably negatively correlated with sucrase. In plowpan, there are no significant correlations among enzyme activities. In subsoil, phosphatase is significantly positively correlated with sucrase, it’s different from the correlation in plough layer.3. With increasing planting years, compared with the control of soil, the pH tends to decline in all layers, and the organic matter, the total soil nitrogen and alkali-hydrolyzable nitrogen content tends to rise, the soil total phosphorus and available phosphorus are tend to rise in plough layer, and have no significant variation in plowpan and subsoil, the soil total potassium and available potassium also have no special variation.4. In plough layer with different planting years, catalase, peroxidase, urease and sucrase are notably or significantly correlated with soil organic matter, total nitrogen, available phosphorus and potassium. Alkaline phosphatase find no correlation with nutrient factors, and pH has correlation with four enzymes except catalase. In plowpan, soil urease is more than notably correlated with avail potassium and phosphorus, and urease is significantly negatively correlated with peroxidase and pH. In subsoil, catalase is notably positively correlated with pH.With increasing planting years, samples enzymes activities are all affected by soil nutrients, and correlations among enzymes and soil nutrients are good. So it’s available to use soil enzymes to evaluate after modified rice soda saline nutrient and fertility.