Mechanisms of Species Loss and Biotic Homogenization in Forest Herb Communities II.

森林草本群落物种丧失和生物同质化的机制II。

• 批准号: 0236333
• 负责人: Donald Waller
• 金额: $ 30万
• 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: 2003
• 资助国家: 美国
• 起止时间: 2003-09-01 至 2007-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0236333&HistoricalAwards=false
• 关键词: Mechanisms; Species; Loss; Biotic; Homogenization

Mechanisms of Species Loss and Biotic Homogenization in Forest Herb Communities II.Waller, Donald M.University of Wisconsin-MadisonHistorical data for northern forests and southern prairies of Wisconsin reveal systematic declines over the past 50 years in rare species and species richness. Several mechanisms might account for these losses including shifts in disturbance regimes, invading weedy exotics, overabundant herbivores, stress from acid deposition and climate change. This project will test these potential mechanisms by examining detailed patterns of change in understory plant communities. This project exploits a unique data set compiled by Curtis and colleagues in the early 1950's that provides accurate baseline data on species occurrences and abundances across hundreds of sites. More than 70 forest sites in southern Wisconsin will be resurveyed to determine the nature, rates, and causes of ecological change in these communities. These results will be compared to the historical Curtis data to chart changes in over-story and under-story composition, invasions by exotics, and rates of species loss and biotic homogenization. Overall, 11 alternative mechanisms of species loss (succession, fire suppression, invasion by exotics, climate change, grazing by deer, etc.) will be tested. Detailed site histories and GIS analyses of some sites will allow an assessment of local disturbance history and landscape context. This project exploits a unique historical data set to identify the mechanisms causing plant community changes. It will pinpoint declining species and greatly expand understanding of how overall community composition responds to local and regional conditions. Such results are of broad significance to forest and wildlife managers charged with managing forests, exotics, and keystone herbivores like deer. Finally, the project would support outreach efforts to natural resource managers, educators, and the public to ensure that these results gain broad attention and appropriate responses.

森林草本群落物种丧失和生物同质化的机制 II.Waller, Donald M.威斯康星大学麦迪逊分校威斯康星州北部森林和南部大草原的历史数据揭示了过去 50 年稀有物种和物种丰富度的系统性下降。 有几种机制可能解释这些损失，包括扰动机制的变化、杂草外来物种的入侵、食草动物过多、酸沉积带来的压力和气候变化。 该项目将通过检查林下植物群落变化的详细模式来测试这些潜在机制。 该项目利用了 Curtis 及其同事在 1950 年代初期编制的独特数据集，该数据集提供了数百个地点的物种出现和丰度的准确基线数据。 将重新调查威斯康星州南部 70 多个森林点，以确定这些社区生态变化的性质、速率和原因。 这些结果将与柯蒂斯的历史数据进行比较，以绘制林上和林下组成的变化、外来物种的入侵以及物种丧失和生物同质化的速度。 总体而言，将测试 11 种物种丧失的替代机制（演替、灭火、外来物种入侵、气候变化、鹿放牧等）。 一些地点的详细场地历史和 GIS 分析将有助于评估当地干扰历史和景观背景。 该项目利用独特的历史数据集来识别导致植物群落变化的机制。 它将查明正在衰退的物种，并极大地扩展对整体群落组成如何响应当地和区域条件的理解。 这些结果对于负责管理森林、外来物种和鹿等主要食草动物的森林和野生动物管理者具有广泛的意义。 最后，该项目将支持对自然资源管理者、教育工作者和公众的宣传工作，以确保这些结果得到广泛关注和适当回应。