中国农业科学 ›› 2013, Vol. 46 ›› Issue (22): 4733-4744.doi: 10.3864/j.issn.0578-1752.2013.22.011

• 土壤肥料·节水灌溉·农业生态环境 • 上一篇    下一篇

扩散限制和环境筛选对子午岭森林群落构建的相对贡献

 王世雄, 郭华, 王孝安, 范玮熠   

  1. 陕西师范大学生命科学学院,西安 710062
  • 收稿日期:2013-04-28 出版日期:2013-11-15 发布日期:2013-10-05
  • 通讯作者: 通信作者王孝安,E-mail:wangxa@snnu.edu.cn
  • 作者简介:王世雄,Tel:13571987724;E-mail:wangshix812@163.com
  • 基金资助:

    国家自然科学基金(31100311)、陕西师范大学中央高校基本科研业务费专项资金(GK201302023)

Dispersal Limitation Versus Environment Filtering in the Assembly of Plant Communities in the Ziwu Mountains

 WANG  Shi-Xiong, GUO  Hua, WANG  Xiao-An, FAN  Wei-Yi   

  1. College of Life Sciences, Shaanxi Normal University, Xi’an 710062
  • Received:2013-04-28 Online:2013-11-15 Published:2013-10-05

摘要: 【目的】改善区域生态环境是促进农业生产、实现可持续发展的重要前提,而加强植被的恢复重建是改善生态环境的重要途径。本研究拟通过对黄土高原子午岭森林群落构建过程的研究,为该区的植被恢复重建提供理论依据。【方法】采用典范变异分解和Mantel检验两种互补的方法,通过分离环境因子/距离(度量环境筛选)和空间因子/距离(间接度量扩散限制)对群落物种组成/距离的相对贡献,确定环境筛选和扩散限制在该区植物群落构建中的相对重要性。【结果】不同群落类型间的物种组成差异显著,空间和环境因子共同解释了草本、灌木、乔木三层29%—65%的物种组成变异(P<0.01)。而二者的贡献特点在不同层次有所差异,乔木层和灌木层主要以空间因子为主导;而在草本层中,空间和环境因子具有相似的贡献率。草本、灌木、乔木三层的物种非相似性距离与环境距离和地理距离都显著相关(P<0.05),草本层具有较大的环境距离相关系数,而灌木层和乔木层具有较大的地理距离相关系数。【结论】扩散限制和环境筛选相互作用,共同影响着黄土高原森林群落的构建过程。本研究的结果并没有否定环境筛选在黄土高原群落构建中的重要性,而是更加强调了扩散限制在该区的主导性。因此,在黄土高原森林群落的恢复重建中,应该同时考虑环境异质性和地理空间的差异性。

关键词: 生态位理论 , 中性理论 , 群落相似性 , 典范变异分解 , Mantel检验

Abstract: 【Objective】Improved regional eco-environment is critical to forming ecologically sustainable land-use policies and accelerating agricultural production. Restoring natural vegetation is one of the effective approaches to improve the ecological conditions, and understanding what governs community assembly is the first step, but has been a continuing challenge for ecologists.【Method】In the Ziwu Mountains of the Loess Plateau, how the community assembly is affected by environmental filtering and dispersal limitation was examined by using canonical variation partitioning and Mantel tests, i.e. partition the variation of community composition/dissimilarity distance between environmental and spatial factors/distance. Three species groups (herb layer, shrub layer and tree layer) that differ in traits of likely importance for environmental filtering and dispersal limitation (height and growth form) were analyzed. 【Result】 All forest types were simultaneously governed by environmental control and spatial processes; together, these processes explain 29% to 65% of the species composition variation (P<0.01). However, the effects of these two processes were varied among species groups; shrub layer and tree layer species were dominated by spatial process while there was similar importance between two processes for herb layer. Mantel and partial Mantel tests showed significant correlations between community dissimilarity and environmental dissimilarity/geographical distance (P<0.05). Herb layer showed a high correlation with environmental dissimilarity while shrub and tree layer displayed high correlations with geographical distance. 【Conclusion】 The assembly of plant communities in the Loess Plateau appears to be simultaneously driven by environmental filtering and dispersal limitation. This case study shows the importance of the dispersal limitation in understanding the forests assembly in the Loess Plateau. Consequently, it is important that management planning for restorations of natural vegetations take into account both habitat heterogeneity and geographical differences.

Key words: niche assembly , neutral assembly , community similarity , canonical variation partitioning , Mantel test