不同养殖密度的林下养鸡对林地植被及环境质量影响

目的]中国山区的坡耕地实施退耕还林、封山育林后,许多山区农民无地可种,无业可就.为解决坡耕地退耕后山区劳动力赋闲,收入低下的问题.方法]基于在北京北部山区开展的20个林下养殖小区,5条土壤健康监测样线,6个水质监测径流小区,以及60个植物损耗小区进行的不同养鸡密度试验,监测不同养鸡密度下每个养殖小区的植被、土壤、地表水等环境质量因子的变化,采用澳大利亚国立大学景观功能方法LFA(Landscape Function Analysis)、土壤健康评价方法(SSA)和地表水质量标准对比法,分析不同养殖密度的林下养鸡对林地植被及环境质量的影响.结果]结果表明,林下养鸡超过一定密度,对林地环境质量有明显影响.养鸡密度越大,对林地植被及环境质量的负面影响越大.密度超过450只/hm2,对植被、土壤及地表水均造损害.结论]在林下养鸡要根据环境承载力控制适宜养殖密度,并实行科学的轮牧和补饲,实现林区生态与经济的和谐发展.该研究结果可以为山区林下养殖经济的发展提供科学依据.

The effects of chicken raising in woods with different breeding density on the vegetation and environmental quality

Many farmers have lost their lands and jobs after farmlands replanted with trees.In order to increase farmers’ income and employment,experiments were conducted to evaluate the effects of chicken raising in woods with different breeding density on the vegetation and environmental quality with the method of LFA (Landscape Function Analysis),soil sustainable assessment(SSA)and the comparison of quality standards of surface water,the authors supervised the changes of the qualities of soil,vegetation and surface water in 20 chicken-raising plots,5 sample transects of soil quality,6 runoff plots for observation of water quality and 60 plots of plant spoilage.Results showed that chicken raising over a certain level of breeding density had an obvious effects on environmental quality.The bigger the breeding density,the greater the negative effects.Chicken raising over 30 chicken per acre had damages on vegetation,soil and surface water.An appropriate breeding density and rotation grazing are the keys to the harmonious development of ecology and economy in forest.This research provides insight into the development of poultry farm under forest.