Biodiversity patterns in disturbed landscapes

与当前生物多样性危机相关的植物群落跨空间和时间的同质化越来越多地记录在位于城市矩阵的自然栖息地中。然而，预测何时会发生同质化并确定其原因需要进一步调查，以成功地进行保护规划。我的研究项目旨在了解在人为景观中孤立的自然栖息地是如何被改造的。在接下来的五年里，我将使用基于分类学和功能（植物性状）多样性方面的多种方法。首先，我将研究森林和湿地，以评估压力制度，如淹水条件，是否可以调节社区对城市发展的反应。在城市化水平低和高的地区，我将比较森林、完整的沼泽和受排水影响的沼泽，例如那些因道路建设而与水文补给断开的沼泽。我假设随着城市化的发展，mesic森林植物群将变得更加同质化，而森林湿地植物群将变得更加多样化。对于后者，环境压力（涝渍条件）的释放确实会为物种建立创造新的条件，植物繁殖体将由城市基质提供。随着时间的推移，湿地和mesic林的植物群将变得更加相似。其次，我将比较住宅和工业部门的森林，以评估城市干扰类型细微变化的影响。这些部门的绿色和不透水区域的比例可能相似，但在空气质量、传粉者活动以及公民行为方面可能有所不同。除了标准的植物调查，我将取样地衣作为空气污染的生物指标。在一项植物计实验中，三种植物的个体将被移植到住宅和工业部门的几个森林中，作为哨兵植物来测量传粉者的活动。道路将被用作检测公民使用森林的代理。笔者假设，与周边基质的土地利用相比，居住区域的原位干扰（市民访问）是分类同质化的更强驱动因素，但工业发展中普遍存在的污染和授粉减少是与功能同质化相关的因素。第三，利用Baillargeon（1981）的历史数据，研究曲海贝城高原不同生境物种组成的变化。将选择森林、悬崖、铁路和电力线ROW以及沿海沼泽的复制品并进行重新调查。我假设同质化/分化将取决于原始栖息地的两个重要梯度：原始自然性和环境压力。这个研究项目解决了生物多样性分布的关键问题，旨在提高我们在人类改造景观中有效指导保护和管理决策的能力。

The homogenization of plant communities across space and time, associated with the current biodiversity crisis, is increasingly documented for natural habitats located in urban matrices. Yet, predicting when homogenization will occur and identifying its causes require further investigation for successful conservation planning. My research program aims to understand how natural habitats isolated in anthropogenic landscapes are being transformed. Over the next five years, I will use multiple approaches based on both taxonomic and functional (plant traits) aspects of diversity. First, I will study forests and wetlands to assess whether stress regime, such as waterlogged conditions, can modulate the response of communities to urban development. In districts with low and high urbanization levels, I will compare forests, intact swamps, and swamps that have been affected by drainage, such as those disconnected from their hydrological recharge by road construction. I hypothesize that mesic forest flora will become more homogenized with urbanization, whereas forested wetland flora will diversify. For the latter, the release of environmental stress (waterlogged conditions) will indeed create new conditions for species establishment for which plant propagules will be supplied by the urban matrix. Over time, wetland and mesic forest floras will become more similar. Second, I will compare forests of residential and industrial sectors to assess the impacts of fine variations of urban disturbance types. These sectors may have similar ratios of green vs impervious areas, yet may differ in respect to air quality, pollinator activity, as well as citizens' behavior. In addition to standard plant surveys, I will sample lichens as bioindicators of air pollution. In a phytometer experiment, individuals of three species will be transplanted in several forests of residential and industrial sectors and used as sentinel plants for measuring pollinator activity. Paths will be used as a proxy for detecting citizens' use of forests. I hypothesize that in situ disturbance (citizens' visits) in residential sectors is a stronger driver of taxonomic homogenization than land-use in the surrounding matrix, but that pollution and reduced pollination prevailing in industrial developments are factors associated with functional homogenization. Third, I will use historical data from Baillargeon (1981) to study changes in species composition for a variety of habitats within the Québec City plateau. Replicates of forests, escarpments, railways and Power-line ROW, and coastal marshes will be selected and resurveyed. I hypothesize that homogenization/differentiation will depend on two important gradients across original habitats: original naturalness and environmental stress. This research program addresses crucial questions about biodiversity distribution and aims to increase our ability to effectively guide conservation and management decisions in human-modified landscapes.