Indigenous peoples’ habitation history drives present-day forest biodiversity in British Columbia's coastal temperate rainforest

Abstract

Long-term human habitation has transformed the earth's surface. The combination of time and complex human–environment interactions in remote regions of North America has likely resulted in modified landscapes, though we often consider these regions free of human influence due to the absence of industrial development. We examined long-term impacts of human resource-use on British Columbia's coastal rainforest communities. We focused on the region's widespread habitation sites with extensive shell middens to test the legacy of ancient human occupation in present-day plant communities. Ten habitation sites and 10 control sites in similar locales were selected for floristic surveys and soil sampling. We tested whether plant communities at habitation sites reflected a ‘cultural plant-use legacy’, with greater presence of culturally significant plant species, and/or a ‘marine nutrient subsidy legacy’ from human use, with increases in species that prefer nutrient-rich soils. We found that the habitation sites had different plant assemblages than the control sites and were dominated by plants with both higher nutrient requirements and cultural significance. We demonstrate that long-term occupation has led to strong differences in plant community structure between sites, countering the notion that this is a pristine landscape. We emphasize the value of interdisciplinary approaches and considering past human resource-use when examining current plant communities. A plain language summary is available for this article.