The Impacts of Human Activities on Ecosystems within China’s Nature Reserves

Wei Cao,Ping Zhu,Lin Huang,Tong Xiao,Jun Zhai

doi:10.3390/su11236629

Abstract

Protected areas (PAs) provide refuges for threatened species and are considered to be the most important approach to biodiversity conservation. Besides climate change, increasing human population is the biggest threat to biodiversity and habitats in PAs. In this paper, the temporal and spatial variations of land cover changes (LCC), vegetation fraction (VFC), and net primary productivity (NPP) were studied to present the ecosystem dynamics of habitats in 6 different types of national nature reserves (NNRs) in 8 climate zones in China. Furthermore, we used Defense Meteorological Satellite Program/Operational Linescan System (DMSP/OLS) nighttime light datasets and the human disturbance (HD) index estimated from LCC to quantify the living and developing human pressures within the NNRs in the period 2000–2013. The results showed that (1) the living human activities of NNRs increased apparently in the humid warm-temperate zone, Qinghai-Tibet Plateau, mid-temperate semi-arid zone, and mid-temperate humid zone, with the highest increase of nighttime light observed in inland wetlands; (2) the developing human activities in NNRs indicated by the HD index were higher in the humid warm-temperate zone and mid-temperate semi-arid zone as a result of increasing areas of agricultural and built activities, and lower in the sub-tropics due to improved conservation of forest ecosystems; (3) the relationship between HD and VFC suggests that ecosystems in most NNRs of south-subtropics, mid-temperate arid zone and Qinghai-Tibet Plateau were predominantly impacted by climate change. However, HDs were the prevalent factor of ecosystem dynamics in most NNRs of north-subtropics, mid-temperate semi-arid and humid zones.

Highlights

More than 85% of the vulnerable or endangered species are influenced by the degradation or destruction of habitat, and at least 20% are impacted by severe weather conditions and climate change in terrestrial ecosystems [1,2]
For national nature reserves (NNRs) in subtropics, forest increased by 72.66 km2 in 15 years but decreased over the last 5 years, wetland increased by 15.63 km2, cropland decreased 68.47 km2, and built area increased by 40.95 km2
For NNRs in mid-temperate semi-arid zone, forest and wetland increased by 63.32 km2 and 16.46 km2, respectively; grassland and desert decreased by 51.39 km2 and 156.57 km2, respectively; but built area increased by 104.24 km2

Summary

Introduction

More than 85% of the vulnerable or endangered species are influenced by the degradation or destruction of habitat, and at least 20% are impacted by severe weather conditions and climate change in terrestrial ecosystems [1,2]. With increasing human activity pressure on the earth’s resources, an effective PAs system is one of the most important approaches for the protection of biodiversity [4,5,6], or slowing the loss rate with its value from a social perspective is changing due to a constantly changing society [7]. The validity of PAs increasingly threatened by human activities and climate change. Compared with studies which focused on the impact of climate change, the number of studies which concentrate on expected influence of future LCC on biodiversity falls far behind [2]

Methods

Results

Conclusion