稻鸭共生对稻田水生动物群落的影响

通过稻田共生的田间试验,利用水生动物取样的方法,对稻鸭共生中稻田水生动物的种类及数量进行定性定量分析。结果表明:各类水生动物的种类数与水的动静有关,放鸭越多,种类数越少,水源区最少,为15种;且稻田水生动物种类出现频次的分布符合C.R aunk iaer频度定律。各类水生动物的数目和生物量均按水源区、对照区、少鸭区、多鸭区的顺序下降。用M arga lef多样性指数公式计算各处理的多样性指数,以对照稻田的多样性指数2.15为最高,水源区和放鸭的稻田均不高,放鸭越多,多样性指数越低。

The impact of rice-duck intergrowth on aquatic animals community of rice fields

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.