| This research put forward a new ecological agriculture mode -Rice-Duck ecological management with no-tillage, and studied soil environment, plant characteristics, ecological benefits, social and economical benefits of Rice-Duck Complex Ecosystem with no-tillage in the Hunan Agriculture University and Huilongpu Town of NingXiang at the same time. It aimed at affording scientific basis for comprehensive assessment of this new ecological agriculture mode and establishing solid theoretical foundation for extending it.Study contents of this experiment included: (1) Constructing Rice-Duck Complex Ecosystem mode with no-tillage; (2) Study on impact of this system on soil environment; (3) Study on impact of this system on plant character; (4) Study on ecological benefits, social and economical benefits of this system. Main results for this study are as follows:1. The influence of Rice-Duck Complex Ecosystem with no-tillage upon soil environmentsCompared with tillage(CK), soil bulk density decreased by 2%, soil non-capillary increased 3.28% in 0~5cm soil layer, hi 5~15cm soil layer, soil bulk density have no change and soil non-capillary increased by 1.1%. It showed no-tillage duck-raising was beneficial to improving soil physical characteristics; The contents of soil nutrient increased in 0~5cm soil layer in various degree, compared with CK: organic matter, total N, available N increase 8.8 g/kg, 0.53 g/kg, 77.0 mg/kg, reaching 17.9%, 23.76%, 44.41%, it showed no-tillage duck-raising was beneficial to improving these nutrients; The analyzing of available P, available K showed, duck-raising was beneficial to increasing available P, available K, but no-tillage have no effects on them. The changes of soil nutrients in 5-15cm soil layer didn't show any regular changes, so no-tillage duck-raising can increase the soil fertility of surface layer, but have no effects on middle and lower layer. Eh increased 18.4mv, SRS decrease 83%, resulting in improving of Redox status. The results hereinbefore showed no-tillage duck-raising improved the soil environment obviously.2. The influence of Rice-Duck Complex Ecosystem with no-tillage upon plant characteristicsThe Rice-Duck Complex Ecosystem with no-tillage is beneficial to increasing the paddy's LAI, dry matter weight ,and the a-NA oxidation ability of rice root in the earlierterm and midterm of growth period ,in the latter term, because no tillage resulted in premature senility of rice root, the LAI was affected, but this three were all not in inferior position compared with tillage. The nutrient content of rice plant body increased before heading stage, but decreased after heading stage because of premature senility of rice root, affecting absorption of N, P, K nutrient for paddy. The comparisons of yield characters showed, the effective panicles, total grains per panicle, seed-setting percentage increased, compared with tillage, theory yield, actual yield increased 2.5%, 2.3%, the increment of yield reaching significant level.3. The study on comprehensive benefits of rice-duck complex ecosystem with no-tillageRice-duck complex ecosystem with no-tillage has strong ecological function, producing great ecological benefits: because of duck's eating and moving about at the field, it can control plant diseases and insect pests and weeds effectively by not using pesticide and herbicide, and because it protects the natural enemy, the effects are very stable, cutting down the pollution to the cropland ecosystem greatly. Furthermore, the fluxes of methane emission of late rice in full tillering stage of paddy decrease 22.5%, the total methane emission decreased 40.5% from full tillering stage to boot stage compared with tillage. It can reduce .the globe's greenhouse effects, producing great ecological significance. Also it can save water resources 1300 m3hm-2 through gathering rainwater and sluice of rice-duck complex ecosystem. As to economical effects, it increased the yield and the net income per ha. 4390 Yuan, decreased the consumption of pesticide, herbici...
|
PDF Full Text Request