Plant community ecological strategy assembly response to yak grazing in an alpine meadow on the eastern Tibetan Plateau

Abstract

Predicting the impact of grazing on vegetation structure, and thus on ecosystem services, is one of the main technical bottlenecks in alpine grassland conservation and management. However, past researches based on the fixed, discrete, and qualitative indicators limited our understanding for the effect of grazing on plant community assembly. Research based on the quantitative competitor, stress tolerator, and ruderal (CSR) theory increases the possibilities for analyzing this ecological process. To test the hypothesis that the dominant plant strategy in alpine meadow plant community will shift from S-selection to R-selection with increased grazing intensity, the plant community CSR strategy assemblies among the cold-seasonal grazing meadows along a gradient of grazing intensity were studied on the eastern Tibetan Plateau. The dominant strategy concentrated in the S-selected corner under the low grazing intensity, which provided a direct evidence to the environmental filters in the alpine area, and suggested that species of strong S-selection should dominate the undisturbed alpine grassland plant community. The C-selection of dominant strategies increased (R 2 = 0.431, p = 0.004), and the extent of S-selection decreased with greater grazing intensity; however, the R-selection of them only slightly increased under intermediate grazing intensity and finally decreased under high grazing intensity, reflecting a selective grazing disturbance combined with localized enrichment of soil that can provide microsites for the establishment of competitors. The strong C-selected species may dominate the plant community on the eastern Tibetan Plateau in place of S-selected and R-selected species, if the grazing intensity is continually high.

Soil degradation influences soil bacterial and fungal community diversity in overgrazed alpine meadows of the Qinghai-Tibet Plateau

“…This area is dominated by meadow vegetation, including Stipa capillata , Poa pratensis, and Kobresia spp. The study site was grazed by 20 yaks ( Bos grunniens ) in a year-long continuous grazing system (5 ha), and the grazing intensity was four yaks ha –1 year –1 , which is a high grazing intensity according to Wang, et al 46 . We selected four sites with different degradation levels to represent the degradation intensity (Fig.…”

Grazing alters species relative abundance by affecting plant functional traits in a Tibetan subalpine meadow

“…Grazing by domestic livestock is one of the most globally widespread land uses, which has led to dramatic changes in plant community composition and species diversity (Chapin et al., 2000 ; Li et al., 2017 ). Thus, there is an urgent need to better understand how grazing alters plant community assembly—if we are to restore plant diversity in the grazed meadows (Wang et al., 2018 ).…”

“…However, other studies analyzing the response of Australian dry shrub and wood lands found that functional traits show very low power to predict variation in plant species abundance in response to grazing (Vesk et al., 2004 ). Moreover, research in West African savannas, semiarid Australian shrublands, subhumid grasslands, and subalpine and alpine meadows (Cingolani et al., 2005 ; de Bello et al., 2005 ; Díaz et al., 2007 ; Kahmen et al., 2002 ; Klimesova et al., 2008 ; Kühner & Kleyer, 2008 ; Li et al., 2013 ; Meers et al., 2008 ; Niu et al., 2010 ; Wang et al., 2018 ; Yang et al., 2015 ) has failed to reach a consensus that functional traits are indeed good indicators of grazing‐induced differences in species abundance.…”

Joint control of plant ecological strategy by climate, regeneration mode, and ontogeny in Northeastern Chinese forests

“…The simple and effective "StrateFy" tool created by Pierce Red indicates C-selected, blue R-selected, and green S-selected species quantitative approach to natural systems has remained rather limited in China (Wang et al, 2018). To our knowledge, this is the first study to determine the CSR strategies of primary Korean pine forest species.…”

“…However, studies of CSR theory remain very limited in China (Wang et al, 2018), and the overwhelming majority of forest plant species in Northeast China are not represented in the aforementioned database of 3,068 species (fec12722-sup-0003-tables1.xlsx) (Pierce et al, 2017); the CSR strategies of these species remain unknown. Within-species variability in CSR strategy also remains poorly characterized, yet may be significant.…”