Microhabitat locality allows multi-species coexistence in terrestrial plant communities.

Jerrold M Tubay,Jin Yoshimura,Keisuke Suzuki,Atsushi Ishida,Hiromu Ito,Katsuhiko Yoshida,Shigeta Mori,Satoru Morita,Masayuki Yokozawa,Takashi Uehara,Jomar F Rabajante,Satoshi Kakishima

doi:10.1038/srep15376

Abstract

Most terrestrial plant communities exhibit relatively high species diversity and many competitive species are ubiquitous. Many theoretical studies have been carried out to investigate the coexistence of a few competitive species and in most cases they suggest competitive exclusion. Theoretical studies have revealed that coexistence of even three or four species can be extremely difficult. It has been suggested that the coexistence of many species has been achieved by the fine differences in suitable microhabitats for each species, attributing to niche-separation. So far there is no explicit demonstration of such a coexistence in mathematical and simulation studies. Here we built a simple lattice Lotka-Volterra model of competition by incorporating the minute differences of suitable microhabitats for many species. By applying the site variations in species-specific settlement rates of a seedling, we achieved the coexistence of more than 10 species. This result indicates that competition between many species is avoided by the spatial variations in species-specific microhabitats. Our results demonstrate that coexistence of many species becomes possible by the minute differences in microhabitats. This mechanism should be applicable to many vegetation types, such as temperate forests and grasslands.

Highlights

Except for minute differences in microhabitats, and Tilman suggested that such micro-environmental variations can be responsible for the coexistence tree species in temperate forests[1,2]
We introduce the spatial heterogeneity in microhabitats between species in a simple lattice model: a lattice Lotka-Volterra competition model
In the current simulation of 20 initial species in a lattice Lotka-Volterra competition model, more than 10 species persisted with species- and site-specific variability in birth rates

Summary

Introduction

Except for minute differences in microhabitats, and Tilman suggested that such micro-environmental variations can be responsible for the coexistence tree species in temperate forests[1,2]. Takenaka’s model is in line with prominent studies relating spatial heterogeneity and coexistence such as those of Chesson, Muko and Iwasa which are mostly based on a lottery model for sessile organisms[16,17,18,19]. As stated previously, these models can only maintain coexistence in shorter periods and only for few species. The number of coexisting species increases more than 15 species, when species-specific heterogeneity is introduced in the mortality rates of matured (settled) plants This is in contrast with Muko and Iwasa finding that spatial variation in mortality only leads to coexistence, not in fecundity[19]. We will discuss the general mechanism for species coexistence in animal and plant communities from the spatial heterogeneity of microhabitats or minute niches

Methods

Results

Conclusion