Plant functional groups mediate effects of climate and soil factors on species richness and community biomass in grasslands of Mongolian Plateau

Autor: Ying Zheng, Xuze Tong, Wenhong Ma, Zhenhua Dang, Lixin Wang, Cunzhu Liang, Frank Yonghong Li, Maowei Liang, Pierre Mariotte, Lei Dong, Zhiyong Li, Indree Tuvshintogtokh, Elise S. Gornish, Jing Hui Zhang, Zijing Li, Lu Wen, Liqing Zhao
Rok vydání: 2021
Předmět:
Zdroj: Journal of Plant Ecology. 14:679-691
ISSN: 1752-993X
DOI: 10.1093/jpe/rtab021
Popis: Aims Functional group composition of a plant community is mainly driven by environmental factors and is one of the main determinants of grassland biodiversity and productivity. Therefore, it is important to understand the role of plant functional groups (PFGs) in mediating the impact of environmental conditions on ecosystem functions and biodiversity. Methods We measured plant biomass and species richness (SR) of grasslands in 65 sites on the Mongolian Plateau and classified 157 perennial herbaceous plants into two main PFGs (namely grasses and forbs). Using the random forest model and ordinary least squares regression, we identified that environmental factors (i.e. aridity index, soil total nitrogen [STN] and pH) were significantly related to the SR and aboveground biomass (AGB) of PFGs. We then used structural equation modeling to explore the relationship between the identified environmental factors and community SR and biomass, and the role of PFGs in driving this relationship. Important Findings We found that aridity index had unimodal relationships with both AGB and SR of the PFGs and the whole community. All SR and biomass metrics were significantly related to STN and pH. The relationship between aridity index and community biomass was mediated by an increase in the AGB of grasses. The influence of STN and pH on community SR was mainly due to their regulation in the SR of forbs. Our results indicate that community composition and the identity of the PFGs play a key role in linking environmental factors to ecosystem functioning.
Databáze: OpenAIRE