Main environmental variables influencing the abundance of plant species under risk category

Pablo Antúnez

doi:10.1007/s11676-021-01425-6

Abstract

Determining climatic and physiographic variables in Mexico's major ecoregions that are limiting to biodiversity and species of high conservation concern is essential for their conservation. Yet, at the national level to date, few studies have been performed with large data sets and cross-confirmation using multiple statistical analyses. Here, we used 25 endemic, rare and endangered species from 3610 sampling points throughout Mexico and 25 environmental attributes, including average precipitation for different seasons of the year, annual dryness index, slope of the terrain; and maximum, minimum and average temperatures to test our hypothesis that these species could be assessed with the same weight among all variables, showing similar indices of importance. Our results using principal component analysis, covariation analysis by permutations, and random forest regression showed that summer precipitation, length of the frost-free period, spring precipitation, winter precipitation and growing season precipitation all strongly influence the abundance of tropical species. In contrast, annual precipitation and the balance at different seasons (summer and growing season) were the most relevant variables on the temperate region species. For dry areas, the minimum temperature of the coldest month and the maximum temperature of the warmest month were the most significant variables. Using these different associations in different climatic regions could support a more precise management and conservation plan for the preservation of plant species diversity in forests under different global warming scenarios.

Highlights

The extinction risk of a species is linked, among other factors, to its limited plasticity and capacity to adapt to rapid changes in environmental factors
Antúnez or rare) to the individual fluctuations of some covariates is insufficient. It is not known which of the species listed in the Official Mexican Standard for native species in a given risk category (NOM-059 2010), or in the IUCN Red List, are the most vulnerable to changes in the precipitation regime of any specific period of the year (e.g., April–September, the growing season precipitation), or to the reduction of the global average precipitation, which seems to be up to 3% in subtropical land areas (Watson and Albritton 2001)
The individual effect of each variable changed in both intensity and magnitude, contrasting in many cases (Table S4), even when comparing among species of the same vegetation type, as in the case of C. caroliniana whose response was negative to variation in summer precipitation (SMRP), while P. menziesii showed a positive relation to SMRP (Fig. 3a; Table S4)

Summary

Introduction

The extinction risk of a species is linked, among other factors, to its limited plasticity and capacity to adapt to rapid changes in environmental factors (e.g., temperature or precipitation; Walther et al 2002). Identifying variables that limit or enhance the presence or abundance of species with high conservation or economic values is a valuable step in characterizing their habitat (Antúnez et al 2017b), given the complex task of elucidating the behavior of each species in a multidimensional space (Hutchinson 1957; Zhu et al 2021) Such information is essential for adequate monitoring of natural populations of high ecological, social, economic or any other value (NOM059 2010), for designing and promoting rational use and conservation actions, such as assisted migration in the face of progressive changes in the environment (Rice and Emery 2003; Sáenz-Romero et al 2012; Gómez-Ruiz et al 2020). Nor has the response of these species to the change of a temperature variable been described (e.g., the minimum or maximum temperature of the warmest month)

Methods

Results

Discussion

Conclusion