Long‐term drought aggravates instability of alpine grassland productivity to extreme climatic event

Abstract

The frequency and severity of extreme weather events are increasing and expected to increase more in the future, together with global change. However, how extreme events and global change factors interactively influence community structures and ecosystem processes is largely unknown. Here, we investigated the responses of the temporal stability and resilience of aboveground net primary productivity (ANPP) of an alpine meadow to an extreme flooding event under different treatments of experimental drought and clipping. We found that ecosystems that were exposed to drought treatments for 3 years significantly decreased the temporal stability of community productivity but increased resilience to flooding, whereas their resistance to or recovery from flooding did not change.Neither clipping nor its interaction with drought altered the responses of these community stability metrics to flooding. Drought treatments significantly decreased plant species richness and asynchrony and dominant species stability, leading to a decrease in temporal stability and an increase in resilience in response to the extreme flooding event. The study also revealed that the change in species asynchrony was the dominant impact pathway determining the responses of resilience and temporal stability to flooding. Our results highlight that alpine grassland that experiences a multiyear drought may aggravate the instability of community productivity to extreme climatic events by reducing species asynchrony.

Latitudinal patterns of forest ecosystem stability across spatial scales as affected by biodiversity and environmental heterogeneity

“…Specific environmental drivers might be important for plant community assembly processes, and thus ecosystem functioning and its long‐term sustainability at a broader scale, and might exhibit significant spatial differences along natural gradients (Burrows et al, 2011; Loarie et al, 2009; Nishizawa et al, 2022). We identify four environmental drivers that can influence ecosystem stability: (i) Climatic history of a region is an important abiotic factor that may influence system processes and the response of ecosystem functioning to climatic perturbations (He et al, 2022; White et al, 2022). Ecosystem stability at the landscape scale is known to be associated with climatic history (White et al, 2022).…”

Effects of Grazing, Extreme Drought, Extreme Rainfall and Nitrogen Addition on Vegetation Characteristics and Productivity of Semiarid Grassland

“…The 2011 IPCC report clearly points out that global climate change is likely to increase the intensity and frequency of extreme climate events, such as severe drought and heavy precipitation, at global and regional levels in the future [13], which is mainly reflected in significant changes in the total amount and distribution of rainfall [14,15]. Drought can inhibit plant growth and reduce coverage, diversity and productivity [16,17], affecting the persistence and distribution of plant species and negatively affecting seedling survival [18]. Increasing rainfall can promote soil microbial activities, change soil-nitrogen-use efficiency and ultimately improve productivity [19].…”

Warming stabilizes alpine ecosystem facing extreme rainfall events by changing plant species composition

“…Flooding, as a typical extreme rainfall event, has been widely reported to threaten ecosystem stability (Fischer et al, 2016; He et al, 2022; Isbell et al, 2015; Wright et al, 2015), which is essential for providing sustainable ecosystem functions and services for humans (Furey & Tilman, 2021; Ma et al, 2022; Tilman et al, 2014). For example, flooding events have been reported to reduce the temporal stability of community productivity in grassland ecosystems (He et al, 2022; Wright et al, 2015). Since flooding events often happen with climate warming (Bevacqua et al, 2022), the change of ecosystem stability due to flooding events may be influenced by climate warming.…”

“…Climate warming, the primary catalyst for extreme climatic events since the hydrological cycle intensifies under higher temperatures (Dai, 2013; Zhang et al, 2021), is predicted to increase the frequency and intensity of extreme rainfall events at the regional and global scales (Bevacqua et al, 2022; Fischer et al, 2013; Huntington, 2006; Pfahl et al, 2017; Wright et al, 2015). Flooding, as a typical extreme rainfall event, has been widely reported to threaten ecosystem stability (Fischer et al, 2016; He et al, 2022; Isbell et al, 2015; Wright et al, 2015), which is essential for providing sustainable ecosystem functions and services for humans (Furey & Tilman, 2021; Ma et al, 2022; Tilman et al, 2014). For example, flooding events have been reported to reduce the temporal stability of community productivity in grassland ecosystems (He et al, 2022; Wright et al, 2015).…”

“…A higher species asynchrony was found to stabilize the temporal stability of community productivity under flooding events through the compensatory effects (He et al, 2022), since the decrease in abundance of one or more vulnerable species is more likely to be compensated entirely by the increase in the abundance of other species (Gilbert et al, 2020; Hooper et al, 2005; Isbell et al, 2009). The stability of dominant species is also reported to play a predominant role in controlling ecosystem stability in facing environmental changes (Grman et al, 2010; Smith & Knapp, 2003), while the rare species are expected to have a weaker impact on temporal stability of productivity due to their lower biomass proportion (Grman et al, 2010; He et al, 2022). Moreover, since different species have different adaptation capabilities to the same environmental perturbation (Liu et al, 2018; Niu & Wan, 2008), the responses of ecosystems dominated by different functional groups to flooding events may vary largely in direction and magnitude.…”