Ecosystem degradation, climate change and tropical ecosystem stability - Tanzania as a case study

未来几十年，非洲热带生态系统将面临前所未有的人为影响，对生态系统的恢复能力构成严重挑战。气候变化导致的不可预测和极端天气条件给这些高度多样化的生态系统带来了额外的压力，对地方、国家和国际生物多样性和人类福祉产生不利影响。为了应对这一发展形势，设计既保护自然又保护人类的环境解决方案，首先必须了解导致生态系统功能和服务提供减少的机制途径；失去韧性；最终导致生态系统崩溃。该项目旨在评估生态系统退化和气候变化对生态系统内部和跨生态系统功能稳定性的影响，预计这些影响将产生最严重的影响：坦桑尼亚。该国是一个著名的生物多样性热点，正在经历气候和土地利用的快速变化。该项目将(1)评估生态系统在日益退化的情况下维持功能的能力，(2)研究生态系统退化如何改变生态系统对环境扰动的抵抗力和恢复力。为了进行这项研究，该项目将重点关注2004-2017年期间收集物种分布的摄像机陷阱信息的27个站点。这些地点面临着不同程度的人为压力：它们代表了一系列保护水平不同的保护区，分布在一系列生态系统类型中。利用来自这27个地点的卫星遥感和地面信息，学生将(i)探索碎片化如何与功能和系统发育多样性以及生态系统功能相关；（ii）评估破碎化如何改变生态系统对自然干扰的抵抗力和复原力，重点是干旱和/或洪水。这项研究的核心成果是增强了对生态系统功能变化与生态系统组成和结构变化之间关系的认识。这一认识将具有直接的应用价值，提高我们保护生物多样性的能力。这项研究还将确定可能对未来生态变化最敏感的生态系统，帮助确定干预的优先次序。

Tropical ecosystems in Africa face unprecedented anthropogenic impacts over the next few decades, posing serious challenges to the resilience of ecosystems. Unpredictable and extreme weather conditions that result from climate change place additional pressures on these highly diverse ecological systems, with detrimental local, national and international impacts for biodiversity and human wellbeing. To address this developing situation, and design environmental solutions that will protect both nature and people, it is essential to first understand the mechanistic pathways that lead to reductions in ecosystem functionality and service delivery; to a loss of resilience; and ultimately to ecosystem collapse.This project aims to assess the impacts of ecosystem degradation and climate change on ecosystem functioning stability within and across ecosystems where impacts are predicted to have some of the most severe effects: Tanzania. The country is a renowned biodiversity hotspot undergoing rapid changes in climate and land use. The project will (1) assess ecosystems' ability to maintain functioning in the face of increased degradation, and (2) examine how ecosystem degradation alters ecosystem resistance and resilience to environmental perturbations. For the purpose of this research, the project will focus on 27 sites where camera-trap information on species distribution was collected over the period 2004-2017. These sites are exposed to variable levels of anthropogenic pressures: they represent a selection of reserves with variable levels of protection and are distributed across a selection ofecosystem types.Using satellite remote sensing and ground-based information from these 27 sites, thestudent will (i) explore how fragmentation relates to functional and phylogenetic diversity aswell as ecosystem functioning; (ii) assess how fragmentation alters ecosystem resistance and resilience to natural disturbances, focusing on droughts and/or floods. A central output of this research is an enhanced knowledge of how changes in ecosystem functions relate tochanges in ecosystem composition and structure. This understanding will be of immediate applied value and improve our ability to safeguard biodiversity. This research will also identify ecosystems likely to be most sensitive to future ecological change, helping prioritise intervention.