林下养鸡对生物多样性的影响

为研究林下养鸡对生物多样性的影响，探讨林下养鸡的可持续性，以浙江临安横路乡生态鸡场为实验点，通过典型样地调查，对生态鸡场山核桃Carya cathayensis林和早园竹Phyllostachys propinqua林下灌木层和草本层的物种多样性指数、丰富度指数、均匀度指数，以及土壤理化性质和土壤微生物数量等进行调查研究，并进行了相关性分析。结果表明:①鸡的活动强度对土壤理化性质和土壤微生物影响显著, 鸡舍附近土壤速效磷、速效钾、水解氮和微生物总数有所增加。②林下养鸡降低了植物多样性，多样性指数与丰富度指数均表现为距离鸡舍越近多样性指数越低。③山核桃林比早园竹林的生物量和凋落物持水量高，有更好的涵养水源功能，更适合发展林下养鸡。这表明在林下养鸡，鸡的活动对样地生物多样性产生了影响。因此在林下养鸡时，通过调控鸡群密度与环境生物多样性的平衡，从而达到林下养鸡的可持续和高效益。图1表8参12

Forest floor fed chickens and biodiversity

To study the influence of feeding chickens from the forest floor，typical investigation were used to obtain species diversity indices of the shrub and herb layers；soil physical and chemical properties；and the number of soil microorganisms in Carya cathayensis and Phyllostachys propinqua forests on the ecological chicken farm in Henglu Town，Zhejiang Province. Results showed 1）that the frequency of chicken activity influenced soil physical and chemical properties and that the number of soil available phosphorus and potassium, hydrolytic nitrogen，as well as the total number of soil microorganisms in the soil near chicken house were increased. 2）Feeding chickens from the forest floor decreased the diversity indices. For example，there were seven kinds of shrub species and twenty-wo kind of herb species in plot A1；the number of shrub species in plot A2 was three and herbs was fourteen；however，in plot A3，there were no shrub or herb left, which indiced that the closer to the chicken house the lower with diversity indices. 3）Also，the C. cathayensis forest had a superior biomass and water holding capacity in the litter layer compared to the Ph. propinqua forest. The C. cathayensis forest had a better water conservation function and was more suitable for raising chickens；therefore, by regulating the balance between the chicken density and biodiversity，greater benefits with sustainable cultivation could be achieved when feeding chickens from the forest floor. ［Ch，1 fig. 8 tab. 12 ref.］