Effect of the Long-Term Mean and the Temporal Stability of Water-Energy Dynamics on China’s Terrestrial Species Richness

Chunyan Zhang,Danlu Cai,Shan Guo,Yanning Guan,Wang Li,Xiaolin Bian,Wutao Yao

doi:10.3390/ijgi6030058

Abstract

Water-energy dynamics broadly regulate species richness gradients but are being altered by climate change and anthropogenic activities; however, the current methods used to quantify this phenomenon overlook the non-linear dynamics of climatic time-series data. To analyze the gradient of species richness in China using water-energy dynamics, this study used linear regression to examine how species richness is related to (1) the long-term mean of evapotranspiration (ET) and potential evapotranspiration (PET) and (2) the temporal stability of ET and PET. ET and PET were used to represent the water-energy dynamics of the terrestrial area. Changes in water-energy dynamics over the 14-year period (2000 to 2013) were also analyzed. The long-term mean of ET was strong and positively ( R 2 ∈ ( 0.40 ~ 0.67 ) , p < 0.05 ) correlated with the species richness gradients. Regions in which changes in land cover have occurred over the 14-year period (2000 to 2013) were detected from long-term trends. The high level of species richness in all groups (birds, mammals, and amphibians) was associated with relatively high ET, determinism (i.e., predictability), and entropy (i.e., complexity). ET, rather than PET or temporal stability measures, was an effective proxy of species richness in regions of China that had moderate energy (PET > 1000 mm/year), especially for amphibians. In addition, predictions of species richness were improved by incorporating information on the temporal stability of ET with long-term means. Amphibians are more sensitive to the long-term ET mean than other groups due to their unique physiological requirements and evolutionary processes. Our results confirmed that ET and PET were strongly and significantly correlated with climatic and anthropogenic induced changes, providing useful information for conservation planning. Therefore, climate management based on changes to water-energy dynamics via land management practices, including reforestation, should be considered when planning methods to conserve natural resources to protect biodiversity.

Highlights

Climate change and human activities are the primary stressors driving the global loss of biodiversity [1]
We extended the hypothesis from using just the long-term mean of ET to include the temporal stability of ET too
We demonstrated how the long-term mean and temporal stability of ET based on remote sensing are correlated with species richness using recurrence quantification analysis (RQA) and linear regression

Summary

Introduction

Climate change and human activities are the primary stressors driving the global loss of biodiversity [1]. The water-energy dynamics, which govern the patterns of global biodiversity [4], have been altered due to climate change and human-induced change [5]. Among the key concepts presented in the published literature, the water-energy hypothesis is a climatically based hypothesis that has become the subject of increased interest. This hypothesis states that the interaction of water and energy generates and maintains the broad-scale gradients of species richness [4,7] by directly or indirectly constraining the physiological and physicochemical processes of plants and animals [8]

Methods

Results

Conclusion