Effects of climatic and biotic factors on the ecology and nutrient dynamics of marshes and shallow open waters in natural and disturbed regions

由于农业/城市扩张和工业用地开发，加拿大西部的湿地正在迅速消失，并因气候变暖而进一步加剧。中部草原省份的大部分地区的气温已经比20世纪中叶高出2-3度，许多湿地的水位正在下降；预计21世纪气温将继续上升。控制营养状态和湿地质量的过程是复杂的，人为干扰和气候变暖使其更加复杂。由于累积干扰，湿地生态系统功能和水质正在退化。我的目标是研究气候/物理和生物因素对北部沼泽和自然和受干扰地区的浅海开放水域的生态和营养动态的影响。我的研究的一个组成部分将是调查在未受干扰的西部北部森林和受干扰的北部过渡/杨树公园地区的浅水湿地湖泊中，自上而下和自下而上控制藻类生产力的作用。根据艾伯塔省的新湿地政策，面临开发的湿地将受到保护，经过修改后进行开发，或者建设新的湿地来取代被破坏的湿地。由于艾伯塔省没有生态系统评估系统，湿地管理者面临的挑战是确定受干扰和恢复的湿地的湿地健康状况。在其他区域，生物评估在量化退化和恢复成功方面取得了成功，但生物评估是针对区域的。在加拿大西部湿地，还没有制定湿地健康指标。我将测量天然参考沼泽和浅水开阔湖泊中的生物、化学和物理因素，并将它们与受干扰的湿地进行对比。浮游和沉水植被、大型无脊椎动物和浮游动物对不同化学和物理条件的生物响应将被量化，并发展为湿地健康的具体指标和指数。我的研究将增加对浅层湿地生态过程的理解，并开发必要的工具来评估湿地健康状况，以便进行生态系统管理。

Wetlands in western Canada have been disappearing rapidly due to agricultural/urban expansion and industrial land development, and are further stressed by climate warming. Most locations in the central Prairie Provinces already have temperatures 2-3 degrees warmer than in the mid 20th century and many wetlands are exhibiting decreased water levels; and temperatures are projected to continue rising during the 21st century. The processes controlling trophic state and wetland quality are complex and are further complicated by anthropogenic disturbance and climate warming. As a result of cumulative disturbances, wetland ecosystem function and water quality are being degraded. My goal is to examine the effects of climatic/physical and biotic factors on the ecology and nutrient dynamics of northern marshes and shallow open waters in natural and disturbed regions. One component of my research will be to investigate the role of top-down vs. bottom-up control of algal productivity in shallow wetland lakes in the undisturbed western boreal forest and the disturbed boreal transition/aspen parkland regions. Under Alberta's new wetland policies, wetlands facing development will be either protected, developed with modifications, or new wetlands constructed to replace destroyed wetlands. The challenge for wetland managers is determining wetland health in disturbed and restored wetlands because there is no ecosystem evaluation system in Alberta. In other regions, bioassessments have been successful in quantifying degradation and restoration success, but bioassessments are regionally specific. In western Canadian wetlands, the development of wetland health indicators has not been done. I will measure the biotic, chemical and physical factors in natural reference marshes and shallow open lakes and contrast them to disturbed wetlands. Biotic responses of emergent and submersed vegetation, macroinvertebrates, and zooplankton to different chemical and physical conditions will be quantified and developed into specific metrics and indices of wetland health. My research will increase the understanding of ecological processes in shallow wetlands and develop the necessary tools to evaluate wetland health for ecosystem management.