Eco-environmental Benefits Of Organic Planting Methods On Paddy Soil Derived From Red Earth

Red paddy soil is one of the leading agricultural soils in southern part of China, especially in Jiangxi Province. In recent years, excessive land utilization and unreasonable application of chemical fertilizers have caused a series of production and environmental ecological issues. Therefore, to clarify characteristics of plant growth and soil fertility in red soil-rice system under organic planting method is an important issue in the agricultural science in this area. Taking an organic farm in Nanchang city, Jiangxi Province as tested project and conventional planting plots close to the farm as the control, eco-environmental benefits indexes including fertility index of soil and basic physiological characteristics of rice plants at 5 different growth stages(tillering stage, booting stage, heading stage, grain filling stage and ripe stage) were determined after treated with functional biological fertilizer in this paper. In addition, basic physicochemial properties of 5 rice samples from north and south of China were determined to evaluate the quality and safety of rice. Main results and conclusions are as follows:(1)Physiological indexes( the carotenoid content, chlorophyll content, POD activity and root activity) of rice in 5 stages of organic rice, consisting with corresponding index of conventional rice, were interspersed with it. Organic planting methods can improve POD activity of rice flag leaves at the boot stage and heading date, increased by 11.34% and 13.63% respectively, meanwhile root activity of rice at booting and heading, by 8.65% and 9.19% respectively, showing organic planting method can guarantee vigorous growth of rice in rice.(2) The change of organic matter, available nitrogen and available phosphate content at 5 stages under organic planting methode fields was lighter than conventional planting method. However, these physicochemical indexes of the soil at ripe stage under organic planting method were higher than that of conventional planting method. Unlike conventional planting method, soil fertility was released slowly under organic planting method to support the nutrient of tested rice.(3)Compare with conventional planting, the soil fertility indexes( p H value, urease activity, acid phosphatase activity, invertase activity, humic acid, fulvic acid content and PQ value) of rice in 5 stages of organic rice, respectively, increased by 16.73%, 20.16%, 7.08%, 15.36%, 10.96%, 7.48% and 3.72%. Showing organic planting method by applied biological fertilizer can increase soil fertility of rice in rice, which through improving acid soil, soil enzyme activity and some solid carbon sink function.(4)The content of quality indicators of rice(water content, amylose content, fatty acids, gel consistency) were determined in this paper, the results showed planting methode have little effect. However, compare with conventional rice, the heavy metales(Cu, Pb and CD) content of organic rice were lower, indicated that organic rice has certain advantages in rice safety. The three heavy metals content( Cu, Pb and Cd) of paddy field soil also express the process, three kinds of heavy metal content of conventional rice was higher than organic paddy fields.In a word, organic farming not only in rice paddy soil fertility in red soil of Jiangxi province and improve soil condition and then protect the physical strength of rice plants, you can also protect the safety of rice.