Four decades of plant community change along a continental gradient of warming

Abstract

17Many studies of individual sites have revealed biotic changes consistent with climate 18 warming (e.g., upward elevational distribution shifts), but our understanding of the 19 tremendous variation among studies in the magnitude of such biotic changes is minimal. 20In this study we re-surveyed forest vegetation plots 40 years after the initial surveys in 21 three protected areas along a west-to-east gradient of increasingly steep recent warming 22However, close examination of the underpinnings of CTI values suggested a high 32 sensitivity to uncertainty in individual species' temperature indices, and so a potentially 33 limited responsiveness to warming. Overall, by testing a priori predictions concerning 34 variation among parks in the direction and magnitude of vegetation changes, we have 35 provided stronger evidence for a link between climate warming and biotic responses than 36 otherwise possible, and provided a potential explanation for large variation among studies 37 in warming-related biotic changes. 38

Disturbances amplify tree community responses to climate change in the temperate–boreal ecotone

“…Hence, the analysis of shifts of relevant functional traits and ecological affinities in communities using large‐scale monitoring data should disentangle the role of different environmental drivers in shaping communities (Violle et al, ). For instance, the community temperature index (CTI) has been used to measure thermophilization in various communities, such as plants, trees, birds and fishes (Becker‐Scarpitta, Vissault, & Vellend, ; Cheung, Watson, & Pauly, ; Danneyrolles et al, ; De Frenne et al, ; Devictor, Julliard, Couvet, & Jiguet, ; Feeley, Hurtado, Saatchi, Silman, & Clark, ; Gaüzère, Jiguet, & Devictor, ). The CTI is a community abundance‐weighted average of the species temperature indices (STI; proxy for species thermal preference computed as the mean temperature of a given species distribution).…”

Forest understorey communities respond strongly to light in interaction with forest structure, but not to microclimate warming

“…Nevertheless, climate change happens at a slower and more continuous pace than our experimental treatment and several studies already showed that long‐term global warming changed understories over the last decade(s) (Becker‐Scarpitta et al ., 2019; Zellweger et al ., 2020; Govaert et al ., 2021; Richard et al ., 2021) but see Becker‐Scarpitta et al . (2017).…”

“…It is clear that species’ responses to warming differ and numerous studies use the mean temperature across a species’ distribution range as a proxy for its thermal tolerance (Becker‐Scarpitta et al ., 2019; Dietz et al ., 2020; Feeley et al ., 2020), hereafter referred to as thermal niche optimum (Vangansbeke et al ., 2021). Similarly, understorey plants differ in their response to light (Tinya et al ., 2019).…”

Effects of experimental warming on vegetative and reproductive growth of Polygonum viviparum in the Qinghai‐Tibet Plateau

“…Temperature can also indirectly affect plants by influencing soil nutrients and moisture (Xu et al 2015, Alatalo et al 2017. The effects of climate warming on vegetative and reproductive growth of plants may change the population dynamics of species, which may affect community composition and ecosystem structure (Zhang et al 2017, Becker-Scarpitta et al 2019. Globally, the average surface temperature over Effects of experimental warming on vegetative and reproductive growth of Polygonum viviparum in the Qinghai-Tibet Plateau land and sea has linearly increased by 0.85°C from approximately 1880 to 2012 (IPCC 2013), and ecosystems at high elevation are more sensitive to climate change than other regions (Casagranda et al 2019).…”