Dissertation Research: The effects of invasive plant species on biodiversity across spatial scales

人类正在有意无意地在全球范围内以越来越快的速度运输物种。其中一些被运输的物种变得高度入侵，导致当地物种的多样性大幅下降。与此同时，一些研究人员指出，入侵物种，特别是入侵植物物种，很少会导致本土物种灭绝，而且相当无害。这些截然不同的观点促使人们质疑入侵植物对环境的危害。这项研究旨在综合这些关于入侵植物对生物多样性的影响的看似相互矛盾的观点。本研究假设入侵植物对生物多样性的影响随空间尺度的变化而变化。具体地说，入侵植物在小尺度上比大尺度上对多样性的负面影响更大。如果入侵植物对群落中常见植物物种丰富度的负面影响大于稀有植物物种，则预计会产生规模依赖效应。这一建议通过以下方式检验尺度依赖假说：(1)对入侵植物在不同空间尺度上的影响的研究进行定量综述，(2)对全美植物入侵群落进行实地调查，(3)受入侵植物影响的常见和稀有植物物种的人口统计学，以及(4)测试哪些机制导致入侵植物在不同空间尺度上的影响差异的实验。这项研究整合了对社区和种群的研究，以了解入侵植物对本地社区的影响，并为如何理解当前和未来生物多样性的丧失提供了一个框架。广泛的影响：在本研究的数据收集期间，该建议将为本科生和高中生提供研究和指导机会。进一步的教育外展将包括在城市学校教授生态学和入侵物种模块，以及为教师和高中生举办为期一天的讲习班。这项研究将继续为本科生和K-12学生，特别是来自代表性不足背景的学生提供机会。公共教育将继续发挥重要作用，为当地自然地区的恢复和入侵物种管理提供公共文章和建议。

Humans are intentionally and unintentionally transporting species around the globe at an increasing rate. Some of these transported species become highly invasive and cause large declines in the diversity of native species. At the same time, some researchers note that invasive species, specifically invasive plant species, rarely cause native species to go extinct and are rather harmless. These contrasting views have prompted people to question the environmental harm caused by invasive plants. This research aims to synthesize these seemingly conflicting ideas about the effects of invasive plants on biodiversity. The hypothesis of this research is that the effect of invasive plants on biodiversity changes depending on spatial scale. Specifically, invasive plants have larger negative effects on diversity at small scales than broad scales. Scale-dependent effects are expected if invasive plants have larger negative effects on the abundance of common plant species than rare plant species in a community. This proposal tests the hypothesis of scale-dependence by conducting (1) a quantitative review of studies that examine the effect of invasive plants at different spatial scales, (2) field surveys of plant-invaded communities across the U.S., (3) demography of common and rare plant species that are affected by invasive plants, and (4) experiments to test which mechanisms cause differences in the effect of invasive plants at different spatial scales. This research integrates studies on communities and populations to understand the effects of invasive plants on native communities and provides a framework for how to understand current and future loss of biodiversity.Broader impacts: This proposal will provide research and mentoring opportunities for undergraduate women and high school students during the data collection for this research. Further educational outreach will involve teaching ecology and invasive species modules at urban schools and day-long workshops for teachers and high school students. This research will continue to provide opportunities for undergraduates and K-12 students, particularly students from underrepresented backgrounds. Public education will continue to be important through public articles and recommendations for restoration and invasive species management at local natural areas.