Temporal stability of grassland metacommunities is regulated more by community functional traits than species diversity

Abstract

Temporal stability in aboveground net primary productivity (ANPP) is influenced by several attributes of plant communities. Identifying the primary regulators of stability and their roles across spatial scales is of both practical and theoretical importance. We assessed effects of species diversity (local or alpha diversity and species dissimilarity between local communities) together with spatial differences in two community functional attributes (mean aboveground biomass and community leaf dry matter content, LDMC) on temporal stability in spring ANPP of restored grassland. Biomass, community LDMC, and species dissimilarity were derived from remote measurements of canopy reflectance of grassland on two soil types. Results demonstrated that productivity at the larger spatial scale of the metacommunity (communities connected by dispersal) was stabilized more by spatial differences in community functional traits than by diversity or community differences in diversity. Spatial differences in community biomass and LDMC stabilized metacommunity productivity by increasing differences in the productivity responses of spatially distinct communities to interannual variation in precipitation, but de‐stabilized ANPP on one soil type by reducing the temporal stability of local communities. Our results demonstrate the utility of remote sensing for quantifying community attributes useful to assess or predict temporal stability of grassland ANPP. We conclude that temporal stability in productivity depended largely on community differences in functional attributes that couple plant growth to changes in resource availability.

Community leaf dry matter content predicts plant production in simple and diverse grassland

“…Aboveground biomass per patch in spring (in grams per square meter; assumed equal to early‐season ANP) was calculated as an exponential function of the enhanced vegetation index (EVI) (adjusted r 2 = 0.83, p < 0.0001; Polley, Yang, et al, 2020b). where NIR, red, and blue are reflectance in near‐infrared, red, and blue wavelengths, respectively; L is an adjustment for canopy background; G is a gain factor; and coefficients C 1 and C 2 correct for the influence of aerosols ( L = 1, C 1 = 6, C 2 = 7.5, and G = 2.5).…”

“…Aboveground biomass per patch in spring (in grams per square meter; assumed equal to early-season ANP) was calculated as an exponential function of the enhanced vegetation index (EVI) (adjusted r 2 = 0.83, p < 0.0001; Polley, Yang, et al, 2020b).…”

Research Progress of Grassland Ecosystem Structure and Stability and Inspiration for Improving Its Service Capacity in the Karst Desertification Control

“…Resilience, resistance and restoration are the main elements in determining whether an ecosystem is stable [ 33 ]. The study of the role of biodiversity, species diversity and functional traits on stability has been the focus of ecosystem research [ 34 , 35 , 36 , 37 ], and they are influenced by multiple factors on multiple scales [ 38 ]. It has been shown that extreme weather and irrational human activities are the main drivers of structural changes in grassland ecosystems [ 39 ], which indirectly alter ecosystem stability, increase the overall vulnerability of grassland ecosystems and reduce their capacity to provide ecosystem services [ 40 ].…”

Traits of dominant plant species drive normalized difference vegetation index in grasslands globally

“…Remote sensing observations might allow this knowledge gap to be closed (Franklin et al, 2017; Polley et al, 2020; Rocchini et al, 2021). Remote Earth observation products have become widely available and allow the assessment of ecosystem functionality and biodiversity (Lausch et al, 2016; Schmidtlein et al, 2012).…”