A new species abundance distribution model including the hydrological niche differentiation in water-limited ecosystems

Abstract

The formation and maintenance mechanism of biodiversity is a key research topic in community ecology. Establishing a model that can be used to explain and predict the changes of community biodiversity is of great significance in facilitating the analysis and protection of biodiversity. How hydrological niche differentiation determines species abundance distribution requires further exploration. In this paper, by analyzing the characteristics of evolutionary stability of plant communities, the evolutionary stability theory of community water resource allocation is studied in water-limited environments. The water consumption of an individual biomass growth is used to quantify the hydrological niche of the species. The arithmetic mean and harmonic mean ratio of the hydrological niche of a species in the community as a new diversity index is used to measure community hydrological niche differentiation. A new hydrological niche plant diversity model is established, and the species abundance curve and species area curve, including the community hydrological niche differentiation factor, are obtained. It was discovered that the distribution model of species abundance was close to the Fisher log series distribution, which unifies and expands the classical diversity theories. The quantitative relationship between the hydrological niche and plant diversity is given. It is proposed that the plant diversity of a community is determined by regionally available water resources and changes in the species abundance that are filtered by the local biological and abiotic environment and driven by the full utilization of water resources.