Persistence and stability of interacting species in response to climate warming: the role of trophic structure

Abstract

Over the past century, the Earth has experienced roughly 0.4-0.8 • C rise in the average temperature and which is projected to increase between 1.4-5.8 • C by the year 2100. The increase in the Earth's temperature directly influences physiological traits of individual species in ecosystems. However, the effect of these changes in community dynamics, so far, remains relatively unknown. Here we show that the consequences of warming (i.e., increase in the global mean temperature) on the interacting species persistence or extinction are correlated with their trophic complexity and community structure. In particular, we investigate different nonlinear bioenergetic tri-trophic food web modules, commonly observed in nature, in the order of increasing trophic complexity; a food chain, a diamond food web and an omnivorous interaction. We find that at low temperatures, warming can destabilize the species dynamics in the food chain as well as the diamond food web, but it has no such effect on the trophic structure that involves omnivory. In the diamond food web, our results indicate that warming does not support top-down control induced co-existence of intermediate species.However, in all the trophic structures warming can destabilize species up to a threshold temperature. Beyond the threshold temperature, warming stabilizes species dynamics at the cost of the extinction of higher trophic species. We demonstrate the robustness of our results when a few system parameters are varied together with the temperature. Overall, our study suggests that variations in the trophic complexity of simple food web modules can influence the effects of climate warming on species dynamics.

Rising Temperature Drives Tipping Points in Mutualistic Networks†

“…In Fig. 3, we show results of 139 networks having nestedness varying in the range (0-0.84) allowing the networks to be exposed to mean habitat temperature (0° – 40° C ) (Vasseur et al 2014, Uszko et al 2017, Kaur and Dutta 2020). We find that nestedness plays a critical role in eluding the first point collapse (the point at which abundance of pollinators in at least one of the nodes falls below 1 × 10 −2 ) at high temperature but have had mixed effects on the final point collapse (loss of species abundance at all the nodes).…”

“…Based on empirical evidence, recent studied have confirmed species biological rates (e.g., birth rate, death rateand parameters (e.g., handling time) as functions of temperature (Scranton and Amarasekare 2017, Uszko et al 2017, Kaur and Dutta 2020. Here, we consider tem-perature dependent species growth rate α i (T ) exhibiting a unimodal symmetric response represented by a Gaussian function (Scranton andAmarasekare 2017, Hatfield andPrueger 2015):…”

Rising temperature drives tipping points in mutualistic networks

“…Based on empirical evidence, recent studies have confirmed species' biological rates (e.g.birth rate, death rate and parameters (e.g. handling time)) as functions of temperature varying in the range 0-40°C [10,[56][57][58][59]. Here, we consider temperature-dependent species' growth rate α i (T ) exhibiting a unimodal symmetric response represented by a Gaussian function [58,60]:…”

Biodiversity conservation in climate change driven transient communities

“…Here, the food web, i.e. the competing, facilitating or otherwise interacting species co-determine the survival of species (Kaur and Dutta 2020;Van der Putten et al 2010). So, knowledge about species interactions is crucial.…”