DISSERTATION RESEARCH: Assessing cloud forest ecotone sensitivity to climate change in space and time

论文研究：评估云林生态交错带对时空气候变化的敏感性

• 批准号: 0808466
• 负责人: Sara Hotchkiss
• 金额: $ 1.19万
• 依托单位: University of Wisconsin-Madison
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-06-01 至 2011-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0808466&HistoricalAwards=false
• 关键词: DISSERTATION; RESEARCH; Assessing; cloud; forest

By the end of this century, the striking climate and ecosystem changes currently seen in the polar Northern Hemisphere will likely span the globe. The biodiverse tropics, for example, are projected to warm by 1-4 degrees C. Tropical climate change is already evident, in the form of melting glaciers, declining precipitation, increasing temperatures, and a more frequent El Nino/Southern Oscillation. This project investigates tropical ecosystem sensitivity to climate change on Haleakala volcano in the Hawaiian Islands, USA. The study area brackets a changing climatic feature, the mean trade-wind inversion, where the cloud forest abruptly switches to shrubland. Tropical montane cloud forests, which are rich in endemic species and provide the vital ecosystem service of water capture and storage, are particularly vulnerable to climate change. To reveal how climate affects vegetation patterns today, this project compares detailed measurements of climate and vegetation in habitats ranging from mesic alpine grassland, through montane shrubland, and across the forestline into cloud forest. This study also uses microfossils preserved in lake sediment to look into the past and investigate how climate affected vegetation over the past ~10,000 years. Finally, this study analyzes tree cores to determine whether aridity controls the sharp upper cloud forest limit. This study combines analyses across broadly different time scales to predict tropical ecosystem sensitivity. Results from this study will guide managers from Haleakala National Park, Hanawi Natural Area Reserve, and The Nature Conservancy who are all actively engaged in controlling invasive species and conserving rare and endangered species across this unique landscape.

到本世纪末，目前北半球极地气候和生态系统的显着变化可能会波及全球。例如，生物多样性丰富的热带地区预计将变暖 1-4 摄氏度。热带气候变化已经很明显，表现为冰川融化、降水减少、气温升高以及更频繁的厄尔尼诺/南方涛动。该项目调查美国夏威夷群岛哈雷阿卡拉火山的热带生态系统对气候变化的敏感性。研究区域具有不断变化的气候特征，即平均信风逆温，云雾林突然转变为灌木丛。热带山地云林富含特有物种，提供重要的水捕获和储存生态系统服务，特别容易受到气候变化的影响。为了揭示气候如何影响当今的植被模式，该项目比较了从中温高山草原到山地灌木丛，再到穿过林线进入云雾林的栖息地的气候和植被的详细测量结果。这项研究还利用湖泊沉积物中保存的微化石来回顾过去，并调查过去约一万年里气候如何影响植被。最后，本研究分析了树芯，以确定干旱是否控制了云林的急剧上限。这项研究结合了广泛不同时间尺度的分析来预测热带生态系统的敏感性。这项研究的结果将为哈雷阿卡拉国家公园、哈纳维自然保护区和大自然保护协会的管理人员提供指导，他们都积极参与控制入侵物种并保护这片独特景观中的稀有和濒危物种。