Understanding and mapping the boreal rain forest: effects of biotic and abiotic factors on arboreal lichen distribution across multiple landscape extents

点击翻译按钮获取中文摘要

Landscape ecology can be described as studying “what you see from an airplane window” – namely land forms, land cover, and land use. Landscape ecologists examine how spatial ecological patterns and processes are linked. Very often, landscape ecologists use data from across a fairly large region to develop models to predict and understand species distributions and habitat requirements. The proposed research uses tools and techniques from this “big picture” branch of science (landscape ecology) and applies it to a small and cryptic group of organisms: lichens. Lichens are important indicators of air quality and forest health. However, because they are small and difficult to find, scientists have very little data on their distribution across large areas. There is also very little understanding about what environmental factors affect why they are located on certain trees and in certain forest stands, but not in others. I will look at lichen distribution from big spatial scales (the island of Newfoundland) to smaller “landscapes” scales (individual trees). This research will carry out field work to sample lichen diversity on across the island of Newfoundland (which has been dubbed “the boreal rainforest” because of its high lichen diversity). Together with my HQP, we will inventory lichen diversity at three different spatial scales. The “mega-scale” will look at lichen distribution across the island to see how they are sensitive to temperature and terrain. Here we will use satellite and GIS data to look at factors influencing where lichens are found in general by comparing the mapped data to lichen survey data. The “meso-scale” will look at how lichen diversity is different between different kinds of forest patches to see how lichens might prefer certain types of trees over others. The “micro-scale will look at lichen patterns on individual trees to see if they are sensitive to changes in height, trunk diameter, or bark type. Here we will use photographs of tree trunks (akin to satellite images or air photos at a much smaller scale) to look at micro-scale patterns in lichen distribution and relate these to fine-scale differences in tree height, humidity and temperature. We will also set up instruments to collect fine-scale information about temperature and humidity to see how these affect lichen occurrence. Across all scales we will develop models that will help us to better understand what forest and micro-climate types are important for lichens, and will help us to predict where important lichen habitats occur in areas where we cannot sample. We can use the research results to monitor lichen abundance and thus get early indications of changes in air quality. Changes in lichen diversity can also indicate changes in forest health in response to climate change or other human disturbances, such as resource development.