Grants and Contributions:

Grant or Award spanning more than one fiscal year. (2017-2018 to 2022-2023)

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 ?

This information is essential in understanding ways that humans might continue to interact sustainably with our environment.