Sun Caili, Chai Zongzheng, Liu Guobin, Xue Sha
State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Northwest A&F UniversityYangling, China.
College of Forestry, Guizhou UniversityGuiyang, China.
Front Plant Sci. 2017 Aug 29;8:1465. doi: 10.3389/fpls.2017.01465. eCollection 2017.
Analyzing the dynamic patterns of species diversity and spatial heterogeneity of vegetation in grasslands during secondary succession could help with the maintenance and management of these ecosystems. Here, we evaluated the influence of secondary succession on grassland plant diversity and spatial heterogeneity of abandoned croplands on the Loess Plateau (China) during four phases of recovery: 1-5, 5-10, 10-20, and 20-30 years. The species composition and dominance of the grassland vegetation changed markedly during secondary succession and formed a clear successional series, with the species assemblage dominated by → altaicus→ . The diversity pattern was one of low-high-low, with diversity peaking in the 10-20 year phase, thus corresponding to a hump-backed model in which maximum diversity occurring at the intermediate stages. A spatially aggregated pattern prevailed throughout the entire period of grassland recovery; this was likely linked to the dispersal properties of herbaceous plants and to high habitat heterogeneity. We conclude that natural succession was conducive to the successful recovery of native vegetation. From a management perspective, native pioneer tree species should be introduced about 20 years after abandoning croplands to accelerate the natural succession of grassland vegetation.
分析草原次生演替过程中植被物种多样性的动态模式和空间异质性，有助于这些生态系统的维护和管理。在此，我们评估了中国黄土高原弃耕地在四个恢复阶段（1 - 5年、5 - 10年、10 - 20年和20 - 30年）次生演替对草原植物多样性和空间异质性的影响。在次生演替过程中，草原植被的物种组成和优势度发生了显著变化，形成了一个清晰的演替系列，物种组合以→ 阿尔泰针茅→ 为主。多样性模式为低 - 高 - 低，在10 - 20年阶段多样性达到峰值，因此符合驼峰模型，即最大多样性出现在中间阶段。在草原恢复的整个时期内，空间聚集模式普遍存在；这可能与草本植物的扩散特性和高栖息地异质性有关。我们得出结论，自然演替有利于本地植被的成功恢复。从管理角度来看，应在弃耕约20年后引入本地先锋树种，以加速草原植被的自然演替。
