摘要
为了研究大型工程建设对脆弱生态系统的影响，以青藏高原高寒草甸区铁路工程迹地植被为对象，分别在青藏铁路建设期（2005年8月）、运行期（2009年8月、2013年8月）对工程迹地进行了3次植被群落调查，样地大小10m×40m，在此基础上利用种间关联性分析的方法，通过对群落特征的方差比率（馏）检验χ2检验和Spearman秩相关系数检验，来探讨群落物种总体关联性和主要种种对间关联性。结果显示：（1）2005年群落平均盖度（35．21±4．41）％，群落内共有物种71种，2009年群落平均盖度（33．42±3．01）％，共有物种78种，2013年群落平均盖度（43．41±3．26）％，共有物种85种。（2）对群落物种总体关联性检验发现群落物种总体关联性均表现为显著正相关，关联程度排列为VR2005〉VR2009〉VR2013,群落趋向松散，抗干扰能力弱。（3）对群落主要物种种对间关联性检验发现成对物种间的正、负联结比例总体呈下降趋势，并且达到显著或极显著的种对数百分比也呈下降趋势，群落内物种间联结强度逐渐降低。（4）在高寒草甸区工程迹地植被恢复8a时间里，部分相同种对之间的关联程度发生变化，中生或者湿生植物减少，耐旱植物种类增加，表明铁路沿线由于生境小气候干旱化和土壤紧实度增加，群落组成发生适应性改变，群落处于从逆向演替向正向演替的过渡阶段，应尽量降低放牧等二次干扰，加速其自然恢复进程。研究旨为探索青藏铁路工程迹地植被恢复规律提供参考。
The construction of the Qinghai-Tibet Railway is a centennial project of the People＇s Republic of China. A large part of this railway is located on alpine meadows （typical vulnerable ecotones characterized by high altitude, low temperatures, and scarce annual precipitation） between the Tanggula Mountains Pass and Damxung County. Because the construction of this railway is inevitably a source of disturbance to the surrounding environment, it is vital to study the revegetation of these severely affected alpine meadows. To understand the community dynamics of the affected alpine meadows, we investigated the vegetation present on the impacted land during the railway construction period （2005）, as well as 4 years （2009）, and 8 years （2013） after the construction period. Eight 10 m x 40 m plots uniformly located between the Tanggula Mountains Pass （91° 43′31.4″ E, 33° 04′ 36.3″ N） and Wumatang （91° 32′ 11.95″ E, 30° 37′ 51.05″ N） were sampled, each with 9 quadrants 1 m × 1 m in size. The data collected included species composition, species coverage, species height, and the population size of each species. To this end, a series of variance ratio （VR） tests, χ2 tests, and Spearman＇s rank correlation coefficient tests were conducted. The results show that the community coverages were （35.21 ± 4.41）%, （33.42±3.01）%, and （43.41±3.26）%, and 71, 78, and 85 species recorded in the year 2005, 2009, and 2013, respectively. After dropping the species with importance values lower than 0.01, we used the 23, 27, and 21 dominant species in our subsequent analyses for the respective periods. Overall, species richness and community coverage increased over time, with the overall interspecific association indices （VR） being larger than 1 （from 2005 to 2013）. In addition, the results of the W statistics （ χ2 0.95N 〈 W 〈 χ2 0.05N ） showed that the overall associations between species in the community were all significantly positive （P 〈 0.05）. The
出处
《生态学报》
CAS
CSCD
北大核心
2016年第20期6528-6537,共10页
Acta Ecologica Sinica
基金
林业公益性行业科研专项经费资助项目(201504401)
国家自然科学基金资助项目(30870231)
关键词
种间关联
高寒草甸
青藏铁路
干扰
青藏高原
interspecific association
alpine meadow
Qinghai-Tibet Railway
disturbance
Qinghai-Tibet Plateau
