The impact of rice-duck intergrowth on aquatic animals community of rice fields
稻鸭共生对稻田水生动物群落的影响

Rice-duck intergrowth is a complex ecological system with natural ecology and artificial interfere.This technology of Rice-duck intergrowth brings the production of paddy field,cultivation and ecological function into full play, and opens a new way of sustainable development for rice and waterfowl production.This paper discussed the influence of rice-duck intergrowth on the species,quantities,diversity and biomass of aquatic animals,which offered a research approach to aquatic animal diversity for rice-duck intergrowth ecosystem,and gave some theoretical directions to reasonably quantify ducks raised and standardize the technology of rice-duck intergrowth.The experiment was conducted on experimental farm of Huazhong Agricultural University,Wuhan,Hubei province.The experiment was designed as 3 treatments,(1) no duck(CK);(2) 4 ducks(D4);(3) 6 ducks(D6) in each plot of 222 m~2.All the treatments were replicated 3 times in randomized blocks design.Ten days after rice replanting,ducks were put in the rice field,and 50 days after duck-raising,the sampling of zooplankton,benthic animals and aquatic insects in different treatment plot and water head field was made.The diversity index was calculated by Margalef method.In the whole period of rice growth,there were no weeding,no pesticide and no fertilizer performed.The result showed that there existed one important relationship between the number of species of aquatic animals and flow of water.The more duck put,the less species.There were 15,27,27,25 groups in CK,4-duck,6-duck and water head field,respectively.The frequency attribution of categories of aquatic animals in rice field was accorded to C.Raunkiaer theory.Both the species number and biomass of aquatic animals decreased with different treatments as an order of water head field,control field,4-duck field and 6-duck field.The diversity index of CK,4-duck,6-duck and water head field treatments were 2.15,2.06,1.85,1.46,respectively,but the difference was not significant.