Linking nutrient acquisition strategies and plant performance to resource gradients for improved agroecology

点击翻译按钮获取中文摘要

Current and future agricultural management challenges associated with soil degradation, land scarcity, water contamination and climate change will have significant impacts on agricultural practices with far reaching consequences for productivity, ecosystem services and food security. Such challenges can be met by integrating multiple species into the agricultural landscape and by examining dominant mechanisms operating in diverse production systems. Despite this, presently, there is still a great deal unknown regarding the dynamic relationships between nutrient availability, light resources and crop performance in mixed agricultural (crop-crop) and agroforestry (tree-crop) systems. The aim of this work, which lies at the interface of biology, geosciences and agrarian management, is to link crop growth to appropriate nutrient supply by using novel stable isotope and rhizosphere techniques. To do this, my research program will examine existing nutrient cycles, nutrient transfer and crop response in multi-species tropical and temperate agricultural systems. Specific objectives are to 1) determine optimal multi-species planting design and agroecosystem management for maximum yields, 2) identify the most advantageous plant-soil and plant-plant interactions, and 3) compare and contrast agroecosystem dynamics in tropical and temperate regions. In the current geopolitical context, the development of nutrient-conserving practices for agriculture in the face of inaccessible or undesirable fertilizer use is on the rise. This is paralleled with a global call for improved agro-diversity and food security. By applying ecological principles to agricultural landscapes, this work will result in sustainable yet attainable practices that improve the efficiency of nutrient cycles and plant-soil interactions in order to increase yields as well as enhance environmental services. Findings from this research program will provide significant information for sound agricultural management prescriptions in high-value tropical systems as well as in the agrarian environment of Canada.