新疆天山云杉林群落分布格局及环境解释

Plant Communities Pattern of Picea tianschanica Forest and Their Interrelations with Environmental Factors in Tianshan Area

[目的]天然林保护工程实施20周年之际,划分新疆天山云杉林群落类型,定量分析天山云杉林群落分布格局与环境及采伐干扰因子之间的关系,为新疆天然林保护工程实施后森林资源恢复评价提供参考依据。[方法]以新疆典型天山云杉森林群落为研究对象,通过野外样方调查,采用双向指示种法(TWINSPAN)对天山云杉林群落进行群落划分,采用冗余分析(Redundancy analysis,RDA)方法对其群落类型进行排序,定量分析森林群落分布格局与环境因子和采伐干扰因子的关系。[结果](1)TWINSPAN将47个森林群落调查样方划分为14个群落类型;(2)RDA排序结果表明海拔、坡度环境因子及森林采伐干扰因子是影响天山云杉群落格局的主要环境因素;(3)因子分离显示出环境变量对森林群落格局解释率达33.9%,采伐强度对森林群落格局解释率占5%,两者共同解释率为17.9%,未解释的部分占43.2%。未能解释的部分主要包括群落之间的相互影响及其他干扰等因素造成。[结论]新疆典型天山云杉林林区新疆农业大学实习林场有14个森林群落类型,其分布格局受环境因子和采伐干扰因子的共同控制,并且二者的交互作用非常显著。森林采伐干扰的强弱是新疆天山云杉林可持续经营不容忽视的重要因素。

[Objective]To classifying the Picea tianschanica forest communities and study the effects of cutting intensity and environmental factors on the community pattern the purpose of sustainable management of Picea tianschanica forest.[Method]Based on field investigation,two-way indicator species analysis(TWINSPAN)was used to classify 47 Picea tianschanica communities,The redundancy analysis(RDA)was used to sort the community types and quantitatively isolate the factors affecting the community pattern.[Result](1)The 47 survey plots were classified into sixteen types of forest communities by TWINSPAN;(2)According to RDA sort diagram,the main environmental factors affecting the communities distribution of Picea tianschanica forest were elevation,slope and cutting intensity of forest.(3)The interpretation rate of environmental variables to forest community pattern accounted for 33.9%,The explanation part of the cutting intensity disturbance factors in the distribution pattern of the community accounts for 5%,the percentage of the interaction between the two factors was about 17.9%.In addition,43.2%of distribution pattern was undetermined.The inexplainable part mainly includes the mutual influence between communities and human interference.[Conclusion]The Picea tianschanica forest in Tianshan composes of 14 community types,the community distribution pattern are controlled by cutting intensity and environment factor.The diversity of community indicates that after the implementation of natural forest protection project,the vegetation restoration is well,and the magnitude of cutting intensity is great significance to forest sustainable management.