Trait‐based climate change predictions of plant community structure in arid steppes

Abstract

Summary1. Global climate change is possibly one of the most important challenges for current and future human populations due to its wide-ranging effects on ecosystems. Global prediction models suggest that in some areas of the world (e.g. Northern Africa, Central America) an increase in aridity might strongly disturb agricultural production and affect food security. To counterbalance these negative effects, reliable predictive models are needed to anticipate ecosystem changes. 2. We tested the ability of the Community Assembly by Trait-based Selection (CATS) model that is based on the principle of maximum entropy and trait-based environmental filtering, to predict actual and future plant community composition in the arid steppes of eastern Morocco. Specifically, we asked whether this model was adequate for predicting actual community composition, based on predicted community-weighted mean (CWM) traits, and what would be the changes in community composition under various scenarios of climate change for the period 2080-2099. 3. The CATS model could predict > 90% of actual community composition if the actual CWM traits were known but only~40% if the CWM values were predicted from estimated aridity and grazing values. The predictions of community composition for 2080-2099 suggested that, regardless of the climate change scenario considered, the dominant group in grazed and ungrazed sites would shift from ruderal species to stress-tolerant sub-shrubs, which would constitute up over 80% of total community composition in some cases. 4. Synthesis. Our findings suggest that effects of climate change will strongly modify plant community structure in arid steppes, possibly accentuating the process of desertification, and reducing the pastoral value of the vegetation. Future research efforts should concentrate on the identification of strong trait-environment relationships to improve model predictions.

The intrinsic dimensionality of plant traits and its relevance to community assembly

“…Community ecologists have sought to insert traits into models to explain the distribution of species along environmental gradients (Bernhardt-R€ omermann et al 2008;Dray & Legendre 2008;Shipley 2010;Kleyer et al 2012;Pollock, Morris & Vesk 2012;Jamil et al 2013), to predict shifts in species distributions in a changing environment Frenette-Dussault et al 2013) and to test the theories of environmental filtering and limiting similarity (Kraft, Valencia & Ackerly 2008).…”

Quantifying multimodal trait distributions improves trait‐based predictions of species abundances and functional diversity

“…; Frenette‐Dussault et al. ). These statistical models implicitly assume that traits are unimodally distributed within each location along the environmental gradient, and therefore emphasize the theory of environmental filtering (Keddy ).…”

CSR analysis of plant functional types in highly diverse tropical grasslands of harsh environments

“…Keeping sight of the fact that there is 15 currently a long list of easily-measured traits that are highly correlated to key physiological traits, ecological processes and ecosystem services (Weiher et al 1999;Cornelissen et al 2003;Díaz et al 2004Díaz et al , 2007, we argue that other herbaceous vegetation types of high priority for conservation should be sampled to identify their dominant species with respect to these functional traits, such as those used in the present study. In this way, valuable information will be made available with relatively little effort, which may be incorporated into conservation and management programs given the relevance of this information to understanding the resilience and resistance of these vegetation complexes to the impacts of climate and land-use change (Suding et al 2008;Frenette-Dussault et al 2013). In this sense, the geographic distribution of species was related to the environmental and functional spectra.…”