The biodiversity and interactions among arthropods and their host plants in canola agroecosystems

我的研究项目以油菜植物群落为模型系统，研究节肢动物食草动物如何与寄主植物相互作用，以及节肢动物在不同营养水平上如何影响植物的结构和功能。在加拿大，油菜籽种植系统很普遍，每年约有400万至500万公顷，并且在几个营养水平上与节肢动物物种的巨大多样性有关。油菜籽系统可以很容易地在结构上和时间上进行操纵，发生在几个生态区，并且可以进行重复实验，使其成为研究昆虫-寄主植物相互作用、昆虫传播模式和昆虫生物多样性随时间和空间变化的机制的理想选择。我的研究包括三个主要主题。首先，我正在努力了解在油菜籽景观中驱动昆虫在时间和空间上分布模式的过程。通过对食草动物及其相关的拟寄生物的传播和迁移模式的调查，并利用地理信息系统技术绘制昆虫密度与导致它们的因素之间的关系，本研究将为昆虫定植过程提供新的知识。这一认识将有助于建立节肢动物群落结构如何应对植物生物和非生物胁迫的预测模型。其次，我将研究在单一栽培和更多生物多样性的环境中，食草动物、捕食者和拟寄生物如何相互作用，以及捕食者和拟寄生物如何间接影响植物生长和植物群落结构。我的第三个研究主题是研究寄主植物质量和植物群落组成的变化如何级联到更高的营养水平，以及一个物种的食草性如何影响植物的形态和功能。来自NSERC发现项目的资金将支持这三个领域的研究生教育，从而促进下一代农业生态学家的培训。

My research program uses canola plant communities as a model system for investigating hypotheses relating to how arthropod herbivores interact with their host plants and how plant structure and function can be affected by arthropods at various trophic levels. In Canada, canola cropping systems are widespread, comprising approximately four to five million hectares annually, and are associated with a vast diversity of arthropod species at several trophic levels. Canola systems can be readily manipulated structurally and temporally, occur in several ecoregions, and accommodate replicated experiments making them ideal for studying mechanisms associated with insect-host plant interactions, insect dispersal patterns, and shifts in insect biodiversity over space and time. My research encompasses three main themes. First, I am working to understand the processes that drive distribution patterns of insects in time and space in canola landscapes. By investigating dispersal and migration patterns of herbivores and their associated parasitoids, and by using geographical information systems technology to draw relationships between insect densities and factors responsible for them, this research will contribute new knowledge of the processes associated with insect colonization. This understanding can then lead to development of predictive models of how the arthropod community structure will respond to plant biotic and abiotic stress. Second, I will investigate how herbivores, predators, and parasitoids interact in monocultures and more biodiverse environments, and how predators and parasitoids can indirectly affect plant growth and plant community structure. My third research theme investigates how variation in host plant quality and plant community composition can cascade to higher trophic levels and how herbivory by one species can affect plant morphology and function. Funding from the NSERC Discovery program would support graduate student education in all three areas, and so facilitate training of the next generation of agroecologists.