Doctoral Dissertation Improvement Award: Aridification and Environmental Change

博士论文改进奖：干旱化与环境变化

• 批准号: 1838393
• 负责人: Douglas Kennett
• 金额: $ 3.17万
• 依托单位: Pennsylvania State Univ University Park
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-09-01 至 2019-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1838393&HistoricalAwards=false
• 关键词: Doctoral; Dissertation; Improvement; Award; Aridification

The intrinsic and economic values of biodiversity make species extinction a significant societal concern. To conserve the existing variety of species, it is important to understand past and present drivers of biodiversity loss. Archaeology and paleoecology provide relevant, long term perspectives on interactions among humans, other organisms, and climate that contribute to extinctions. This project will answer several longstanding questions regarding how a drying climate and the early colonization of Madagascar by humans and associated introduced species may have contributed to past extinctions of large animals on the island. For example, to what extent did humans hunt the now extinct animals? Did introduced animals compete with now-extinct natives, and were introduced animals drought-tolerant relative to natives? Recognizing feedbacks among sources of regional change is a challenge, but this case study of datasets from Madagascar is broadly applicable to the study of past interactions among organisms in the face of aridification. Given the relevance of this research to present environmental concerns and the ongoing development of drought-related policy in arid southwest Madagascar, community and local government outreach is a project priority. This interdisciplinary work involves students and faculty at Malagasy universities, and the students trained through the field component of this research will gain skills applicable to data gathering and natural resource management.This research investigates some of the many ways in which the arrival of humans and introduced species in a novel environment may have contributed to past and ongoing biodiversity loss. The field component of this project focuses on the coast of southwest Madagascar. This region is ideal for studies of environmental changes associated with human activity, because humans and human-introduced animals (e.g. goats, pigs, cattle, dogs, cats, and rats) arrived on the island several thousand years ago, and the bones of extinct endemic animals (e.g. pygmy hippos, giant tortoises, elephant birds, and giant lemurs) are abundant along this coastline. Survey and excavation of a series of coastal ponds with traces of past human presence serve to recover the material record of past human activity and biodiversity loss. Radiocarbon dating of bone recovered from fieldwork and museum collections provides the chronological control that is necessary to infer past interactions among humans, other organisms, and environmental change. A series of chemical analyses of radiocarbon-dated bone protein is used to trace aspects of organisms' diets and environments through time. These analyses, coupled with a separately-funded effort to reconstruct the past climate of the region through the chemical analysis of ancient lake sediments, make it possible to examine potential synergies between past human activity and the changing climate that may have driven past extinctions on the island.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

生物多样性的内在和经济价值使物种灭绝成为一个重大的社会问题。为了保护现有的物种，了解过去和现在的生物多样性损失驱动因素很重要。考古学和古生态学对人类，其他生物体和气候之间的相互作用提供了相关的长期观点，这些观点有助于灭绝。该项目将回答有关人类干燥气候和马达加斯加的早期殖民以及相关的物种如何导致岛上大型动物过去灭绝的几个长期问题。例如，人类在多大程度上狩猎现在灭绝的动物？引入的动物是否与现在灭绝的当地人竞争，并被引入动物相对于当地人而耐旱的动物？认识到区域变化来源之间的反馈是一个挑战，但是对马达加斯加的数据集进行了这个案例研究，这通常适用于面对干旱化时生物体之间过去相互作用的研究。鉴于这项研究的相关性与在西南马达加斯加（South West Madagascar），社区和地方政府外展活动中与干旱相关政策的持续制定是一个优先事项。这项跨学科的工作涉及马达加斯加斯大学的学生和教师，通过本研究的现场成分培训的学生将获得适用于数据收集和自然资源管理的技能。这项研究调查了人类的到来并在新颖环境中引入物种的许多方式可能导致了过去和持续不断的生物多样性丧失。该项目的现场组成部分着重于马达加斯加西南部的海岸。该区域是研究与人类活动相关的环境变化的理想选择，因为人类和人类引起的动物（例如山羊，猪，牛，狗，狗，猫和大鼠）几千年前到达了岛上，以及濒临灭绝的地方性动物的骨头（例如，矮胖的河马，巨型玉米饼，巨型乌龟，大象鸟类和巨型鸟类和巨大的lemelless）是如此之多。一系列具有过去人类存在痕迹的沿海池塘的调查和发掘，可恢复过去人类活动和生物多样性丧失的物质记录。从现场工作和博物馆收藏中回收的骨骼的放射性碳年代定位提供了时间顺序控制，这是推断人，其他生物和环境变化之间过去相互作用所必需的。一系列对放射性碳年代骨蛋白的化学分析用于随着时间的流逝追踪生物体饮食和环境的各个方面。这些分析，再加上通过古湖沉积物的化学分析来重建该地区的过去氛围，这使得检查了过去的人类活动与可能导致岛上过去灭绝的气候变化之间的潜在协同作用，这是NSF的法定任务，并通过评估范围来弥补企业的范围，这是奖励的范围。