Assessing the Effects of Human Activity on the Composition of Tropical Forests

该项目研究人类对热带雨林生态系统的影响。热带雨林以其生物多样性而闻名，其植物学组成可能是在人类长期占领期间通过种植、砍伐和焚烧植物而形成的。另一种可能性是，人类活动在较短的时间尺度上影响了热带雨林的组成，包括最近为获取橡胶和其他产品而密集开采森林的时期。本研究采用多种研究方法，包括热带湖泊沉积物岩心分析、森林植被记录和对当地居民的调查，以确定当地植物使用的变化，从而对这些替代方案进行研究。这种方法的结合有助于分析森林组成随时间的变化，使研究人员能够推断变化发生的时间以及人类活动导致当前模式的程度。研究人员还与当地生态旅游组织合作，提高人们对人类对森林环境影响的认识。该项目还有助于指导和培训多名学生进行生态实地方法和数据分析。人类活动在多大程度上改变了热带雨林一直是地理学家的一个长期问题。为了推断人类对森林的影响，研究人员研究了湖泊沉积物，这些沉积物积累了数千年。对这些沉积物中的花粉和植物化石部分的分析为植物多样性随时间的波动提供了洞察力。研究人员将这些发现与当地民族生物学知识的数据结合起来，使人们能够回顾过去的人类居民可能以有益的方式管理森林的方式。热带森林的历史轨迹与气候预测有关，因为有证据表明，较新的森林以相对较大的速率吸收大气碳。确定森林在不同时间尺度上被修改的程度也有助于深入了解森林对人类活动的适应能力，包括目前对生态系统的影响。该项目还通过与支持保护努力的生态旅游组织建立伙伴关系，为热带环境的保护作出贡献。对研究生和本科生的培训有助于扩大对科学研究的参与。这一奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

This project examines human impacts on rain forest ecosystems. Noted for their biodiversity, the botanical composition of rain forests has potentially been shaped during extended periods of human occupation by the planting, cutting, and burning of plants. An alternative possibility is that human activity affects the composition of rain forests on shorter time scales, including recent periods of intensive exploitation of forests for rubber and other products. This study examines these alternatives though a combination of research methods that includes the analysis of sediment cores from tropical lakes, documentation of vegetation in forested locations, and surveys of local residents to determine variation in the uses of local plants. This combination of methods facilitates analysis of change in forest composition over time, allowing the researchers to infer when changes occurred and the extent to which human activity resulted in current patterns. The researchers also collaborate with local ecotourism organizations to promote greater awareness of human impacts on forested environments. The project also contributes to the mentorship and training of multiple students in ecological field methods and data analysis.The extent to which human activity has modified tropical rain forests has been a longstanding question among geographers. To make inferences about human impacts on forests, the researchers examine lake sediments, which accumulate over thousands of years. The analysis of pollens and plant parts that have fossilized in these sediments provides insights into fluctuations in botanical diversity over time. The researchers combine these findings with data on local ethnobiological knowledge, which permits retrospective insights into the ways that past human inhabitants may have curated the forest in beneficial ways. The historical trajectory of tropical forests is relevant to climate projections given evidence that newer forests absorb atmospheric carbon at relatively greater rates. Ascertaining the extent to which forests have been modified on different timescales also provides insights into the resilience of forests to human activity, including present impacts on the ecosystems. The project also contributes to conservation in tropical settings via partnerships with ecotourism organizations that support conservation efforts. The training of graduate and undergraduate students contributes to the goals of broadening participation in scientific research.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.