中国水稻-动物共作系统对水稻产量与土壤温室气体排放的影响OA

Paddy fields are one of the major sources of greenhouse gases emissions.Rice-animal co-culture systems play an important role in increasing rice yields and reducing greenhouse gases emissions,with their effectiveness being influenced by factors such as different rice cropping pattern,aquatic animal species,stocking density,and nitrogen application rate.On the basis of 248 sets of field experiment data from 76 articles published between 2000 and 2025,a meta analysis was conducted to evaluate the effects of rice-animal co-culture systems on rice yields and greenhouse gases emissions in China,and a random forest model was adopted to quantify the relative importance of different influencing factors.The data from different rice-animal co-culture systems showed that compared with rice monoculture,rice-animal co-culture systems significantly increased the rice yield by 8.16%and reduced CH4 emissions by 16.46%(P<0.05),while the reduction in N2O emissions was not significant.Among these systems,the rice-duck co-culture system outperformed the rice-shrimp and rice-fish co-culture systems in increasing the rice yield and reducing CH4 emissions.The rice yield-increasing and emission-reducing effects of co-culture systems varied under different stocking densities,nitrogen application rates,soil properties,and climatic conditions.A greater rice yield increase(13.02%)was observed in the co-culture systems with a nitrogen application rate of 0-120 kg/hm2 than that(11.78%)with a nitrogen application rate of 120-240 kg/hm2,while the latter showed a greater advantage in CH4 emission reduction.Increasing duck stocking density was found to reduce the yield-increasing effect of co-culture systems,whereas increasing shrimp or fish stocking density enhanced or promoted this effect.The initial soil organic carbon content of 0-20 g/kg was conducive to a greater yield-increasing effect but was unfavorable for CH4 emission reduction.Annual average precipitation of 1 000-2 000 mm favored both the yield-increasing effect and CH4 emission reduction in co-culture systems,whereas higher temperatures(annual average temperature≥20 ℃)showed the opposite effect.The results of the random forest model indicated that the yield-increasing effect of co-culture systems was influenced by nitrogen application rate,initial soil organic carbon content,stocking density,and annual average temperature(P<0.05 or P<0.01),while CH4 emissions from paddy soils were significantly influenced only by annual average temperature.In conclusion,rice-animal co-culture systems in China are influenced by multiple factors,including annual average temperature,annual average precipitation,nitrogen application rate,initial soil organic carbon content,and stocking density.Under suitable climatic and soil conditions,optimizing the rice cropping pattern,stocking density,and nitrogen application rate can help achieve the dual goals of increasing rice yields and reducing greenhouse gases emissions in paddy fields.