How forest gaps shaped plant diversity along an elevational gradient in Wolong National Nature Reserve?

CORC > 生态环境研究中心 > 中国科学院生态环境研究中心 > 城市与区域生态国家重点实验室

	How forest gaps shaped plant diversity along an elevational gradient in Wolong National Nature Reserve?
	Chen Li ; Han Wangya ; Liu Dan ; Liu Guohua
刊名	JOURNAL OF GEOGRAPHICAL SCIENCES
	2019-07
卷号	29 期号:7 页码:1081-1097
关键词	forest gap elevation environmental factors plant diversity subalpine coniferous forest
ISSN号	1009-637X
英文摘要	Understanding the underlying ecological processes that control plant diversity within (-diversity) and among (-diversity) forest gaps is important for managing natural forest ecosystems, and it is also a prerequisite for identifying the formation and maintenance mechanisms of forest plant communities. In this study, we focused on the interrelationships among habitat type (gap/non-gap plots), gap size, elevation and environmental factors, and we explored their effects on plant diversity (-diversity and -diversity). To do this, a total of 21 non-gap (i.e., closed canopy) plots (100 m(2)) and 63 gap plots, including 21 with large gaps (200-410 m(2)), 21 with medium gaps (100-200 m(2)) and 21 with small gaps (38.5-100 m(2)), were selected along an elevational gradient in a subalpine coniferous forest of southwestern China. Using structural equation models (SEMs), we analyzed how forest gaps affected plant diversity (-diversity and -diversity) along an elevational gradient. The results showed that (1) as elevation increased, unimodal patterns of -diversity were found in different-sized gaps, and -diversity showed a consistent sinusoidal function pattern in different-sized gaps. The gap size was positively related to -diversity, but this effect disappeared above 3500 masl. Moreover, the patterns of -diversity and -diversity in non-gap plots were irregular along the elevational gradient. (2) SEMs demonstrated that many environmental factors, such as the annual mean air temperature (AMAT), ultraviolet-A radiation (365 nm, UV-A365), ultraviolet-B1 radiation (297 nm, UV-B297), moss thickness (MT), soil carbon/nitrogen ratio (C/N ratio), NH4-N and NO3-N, were significantly affected by elevation, which then affected -diversity and -diversity. The photosynthetic photon flux density (PPFD), UV-A365 and UV-B297 were significantly higher in plots with forest gaps than in the non-gap plots. Moreover, the PPFD and UV-A365 were positively and directly affected by gap size. Surprisingly, except for the NH4-N and the C/N ratios, the below-ground environmental factors showed little or no relationships with forest gaps. All of these effects contributed to plant diversity. Overall, the above-ground environmental factors were more sensitive to gap-forming disturbances than the below-ground environmental factors, which affected -diversity and -diversity. The predicted pathway in the SEMs of the elevational effects on -diversity and -diversity was relatively complicated compared with the effects of forest gaps. These results can provide valuable insights into the underlying mechanisms driving the diversity-habitat relationship in the subalpine coniferous forests of southwestern China.
内容类型	期刊论文
源URL	[http://ir.rcees.ac.cn/handle/311016/42739]
专题	生态环境研究中心_城市与区域生态国家重点实验室
作者单位	1.Chinese Acad Sci, State Key Lab Urban & Reg Ecol, Res Ctr Ecoenvironm Sci, Beijing 100085, Peoples R China 2.Univ Chinese Acad Sci, Sch Resources & Environm, Beijing 100049, Peoples R China
推荐引用方式 GB/T 7714	Chen Li,Han Wangya,Liu Dan,et al. How forest gaps shaped plant diversity along an elevational gradient in Wolong National Nature Reserve?[J]. JOURNAL OF GEOGRAPHICAL SCIENCES,2019,29(7):1081-1097.
APA	Chen Li,Han Wangya,Liu Dan,&Liu Guohua.(2019).How forest gaps shaped plant diversity along an elevational gradient in Wolong National Nature Reserve?.JOURNAL OF GEOGRAPHICAL SCIENCES,29(7),1081-1097.
MLA	Chen Li,et al."How forest gaps shaped plant diversity along an elevational gradient in Wolong National Nature Reserve?".JOURNAL OF GEOGRAPHICAL SCIENCES 29.7(2019):1081-1097.