Community resilience through subsidies and millenial-scale human impacts in an island biogeography context

我实验室的研究考察了我们在自然界中看到的生物多样性模式的产生过程。 我们越来越多地了解到，这些模式是由气候、物种之间的局部相互作用、栖息地之间的个体扩散以及人类对土地的影响等因素共同驱动的。 我们非常熟悉由于林业活动、资源开发和基础设施建设而丧失的栖息地，这些快速过程可以迅速导致景观生物多样性的变化。气候变化等缓慢但广泛的影响使我们更加重视人类对自然的长期影响。人们不太了解的是，许多我们认为是“原始”的栖息地实际上并不是没有长期的人类影响。 相反，其中一些景观似乎对环境的影响具有很强的适应力，并且显然从这些影响中受益，至少以人类重视的方式受益。我们目前的重点是人类对不列颠哥伦比亚省中央海岸沿海温带雨林的长期影响。在这里，长达13，000年的人类历史以前居住地（由从附近海洋系统收获的大量蛤蜊贝壳组成），文化改造的树木，食用植物，以及令人惊讶的是，在这个沿海温带雨林中有广泛的火灾证据。 我们的研究表明，这些壳贝冢对土壤化学和随后的森林结构的强烈影响。火灾也改变了森林的结构，导致景观上树木的大小和类型发生变化。我们使用各种技术来探索这些长期的人类影响如何相互作用，影响景观。特别是，我们会问这样的问题：取消13,000年的管理制度会产生什么影响？ 与那些没有这些影响的地点相比，人类长期广泛使用的地点之间的森林结构有何不同？此外，我们做了小规模的实验，看看这些模式背后的过程可能会影响生态系统在一般意义上：营养补贴从一个生态系统（如海洋）到另一个（土地）如何影响生物多样性？补贴（来自“自然”和人类资源，如蛤壳）的影响是否改变了我们对岛屿上生物多样性的传统理解？

Research in my lab examines the processes that give rise to the patterns of biodiversity we see in nature. Increasingly we understand that these patterns are driven by a combination of climate, local interactions between species, dispersal of individuals between habitats, and human impacts on the land. We are very familiar with habitat lost though forestry activities, resource development, and infrastructure creation, fast processes that can rapidly lead to changes in biodiversity on the landscape. Slower but extensive impacts like climate change increase our appreciation of the longer-term impacts of humans on nature. Less appreciated is the fact that many of the habitats that we consider "pristine" are not, in fact, free of long periods of human influence. Instead, some of these landscapes appear to be very resilient to impacts in the environment, and clearly have benefited from these impacts, at least in ways that humans value. Our current focus is on the long-term impacts of humans on coastal temperate rainforests on British Columbia's Central Coast. Here, up to 13,000 years of human history is visible on the landscape in the form of former habitation sites (composed of large heaps of clam shells harvested from the nearby marine system), culturally modified trees, food plants, and surprisingly, extensive fire evidence in this coastal temperate rainforest. Our research has shown strong impacts of these shell middens on soil chemistry and subsequently on forest structure. Fire has also changed the structure of the forest, leading to altered sizes and types of trees on the landscape. We use a combination of techniques to explore how these long-term human impacts interact to impact the landscape. In particular we ask questions like what is the effect of removing 13,000 years of a management regime? How does forest structure differ between sites with extensive and long-term human use, compared to those sites where these effects are absent? Further, we do small-scale experiments to see how the processes behind these patterns might affect ecosystems in a general sense: how do nutrient subsidies from one ecosystem (for example the sea) to another (the land) impact biodiversity? Do the effects of subsidies (from "natural" and human sources like clamshells) change our classic understanding of how much biodiversity to expect on islands ?