Browsing by Subject "ECOSYSTEM SERVICES"

Now showing 1 - 4 of 4

Open Access
Defaunation of large mammals alters understory vegetation and functional importance of invertebrates in an Afrotropical forest
(Biological Conservation, 2020-01-01) Lamperty, Therese; Zhu, Kai; Poulsen, John R; Dunham, Amy E
Hunting has reduced or eliminated large-bodied vertebrates in many areas across the tropics, contributing to the global process of defaunation. Elucidating the ecological consequences of hunting has important implications for managing ecosystems and for our understanding of community and ecosystem ecology. We present data collected through a combination of comparative and experimental approaches to assess how faunally-intact and heavily-hunted forests in Gabon differ in understory vegetation structure, macroinvertebrate fauna, ecological processes, and the relative importance of different taxa driving those processes. Our results show that hunted sites had denser understory vegetation and hosted approximately 170 times fewer termites compared to faunally-intact sites. While web-building spiders were positively associated with understory vegetation density, this effect did not translate to significantly higher abundances in heavily-hunted forests. Additionally, the overall rates of decomposition, insectivory, and seed predation/removal on the forest floor appeared robust to both defaunation and the associated increases in understory vegetation density. However, our exclosure experiments revealed that the contribution of invertebrates to decomposition was approximately 25% lower in hunted sites compared to faunally-intact sites. Results suggest potential resilience in this complex ecosystem such that microbial or other taxa not measured in this study may compensate for the reduced functional contribution of invertebrates to decomposition. However, while our results illustrate potential resilience, they also indicate that indirect effects following defaunation, such as increases in the density of understory vegetation, may alter invertebrate communities on the forest floor, with potential consequences for the mechanisms, and therefore the dynamics, driving critical ecosystem processes.
Open Access
Free-ranging livestock threaten the long-term survival of giant pandas
(Biological Conservation, 2017-12-01) Li, Binbin V; Pimm, Stuart L; Li, Sheng; Zhao, Lianjun; Luo, Chunping
© 2017 Elsevier Ltd China has implemented forest policies and expanded protected areas to halt deforestation and protect giant panda habitats. These policies simultaneously encouraged local communities to raise livestock that then freely range in forests. This grazing had unintended consequences. As an alternative livelihood, it has become the most prevalent human disturbance across the panda's range. How do free-ranging livestock impact giant panda habitats and what are the implications for future conservation and policy on a larger scale? We use Wanglang National Nature Reserve as a case study. It has seen a nine-fold livestock increase during past 15 years. We combined bamboo survey plots, GPS collar tracking, long-term monitoring, and species distribution modelling incorporating species interaction to understand the impacts across spatial and temporal scales. Our results showed that livestock, especially horses, lead to a significant reduction of bamboo biomass and regeneration. The most intensively used areas by livestock are in the valleys, which are also the areas that pandas prefer. Adding livestock presence to predictive models of the giant panda's distribution yielded a higher accuracy and suggested livestock reduce panda habitat by 34%. Pandas were driven out of the areas intensively used by livestock. We recommend the nature reserve carefully implement a livestock ban and prioritise removing horses because they cause the greater harm. To give up livestock, local communities prefer long-term subsidies or jobs to a one-time payment. Thus, we recommend the government provide payments for ecosystem services that create jobs in forest stewardship or tourism while reducing the number of domestic animals.
Open Access
Reassessing the conservation status of the giant panda using remote sensing
(NATURE ECOLOGY & EVOLUTION, 2017-11-01) Xu, Weihua; Viña, Andrés; Kong, Lingqiao; Pimm, Stuart L; Zhang, Jingjing; Yang, Wu; Xiao, Yi; Zhang, Lu; Chen, Xiaodong; Liu, Jianguo; Ouyang, Zhiyun
Open Access
The effectiveness of the zoning of China's protected areas
(Biological Conservation, 2016-12-01) Xu, Weihua; Li, Xiaosong; Pimm, Stuart L; Hull, Vanessa; Zhang, Jingjing; Zhang, Lu; Xiao, Yi; Zheng, Hua; Ouyang, Z
Increasing human numbers and aspirations threaten protected areas worldwide. China faces especially strong pressure since many people live inside protected areas. It has sought to balance human needs and conservation goals within them by creating mixed zoning schemes loosely based on UNESCO's Man and the Biosphere Programme. These include strictly-protected core zones, buffer zones allowing limited human use, and experimental zones that examine different land-use options. To test the efficacy of this zoning, we employed field surveys and remote sensing to assess the penetration of agricultural and urban land into 109 national nature reserves in China for 2000 and 2010. Human disturbance was lowest in core zones and highest in experimental zones in both 2000 and 2010. Over this period, 82% of the reserves were unchanged or had decreased human disturbance. Nonetheless, overall human disturbance increased by 7%, 4%, and 5% in the core, buffer and experimental zones respectively. Almost all the increase in the core zone was in four wetland reserves, where human actions converted large areas to agriculture. Some 58% of reserves experienced some human disturbance in core zones in 2010, demonstrating a need for more effective zoning. The findings have broader implications for protected area management globally because they highlight the strengths and weaknesses of zoning for balancing human needs and species conservation.