Nutrient bioavailability and primary production in Lake Simcoe

该应用程序将支持的研究计划是对Simcoe湖的营养物质生物有效性和初级生产力的检查。西姆科湖是安大略省最大的内陆湖，也是加拿大的冰钓之都。它也是8个城市的饮用水来源，并受到营养投入增加的威胁。到目前为止，西姆科湖从未测量过初级生产量，也没有对微生物食物网进行评估。藻类或浮游植物构成了湖泊食物网的基础，了解它们的初级生产量将决定湖泊中可能的鱼类产量。这项研究的主要目的是确定西姆科湖浮游植物群落的极限营养物(S)和初级生产力的差异。正在通过对微生物生物量、生理学和新陈代谢进行全面的全年检查来评估这一点。如果我们能够理解是什么控制了碳的循环，也许我们就可以预测和缓解季节性的低氧，并恢复Simcoe湖的冷水渔业。该项目目前涉及7名高素质人才(HQP)，包括1名博士后研究员、2名硕士研究生、2名本科暑期学生和2名技术人员。本申请书涉及拟议研究所需的四件独立设备。YSI Sonde是一种用于对湖泊水柱进行剖面测量的野外仪器，之所以选择它，是因为它适用于大型湖泊，如Simcoe，在恶劣天气条件下，这些湖泊需要进行深度剖面测量。水PAM是一种专门的荧光计，用于评估水中浮游植物群落的可变荧光，并用于检查浮游植物生理学和提供产量估计。同位素分析仪是一种专门的、廉价的、高效的测量稳定同位素的工具。该分光光度计将用于测量水中溶解的营养物质浓度。

The research program that this application will support is the examination of nutrient bioavailability and primary production in Lake Simcoe. Lake Simcoe is the largest inland lake in Ontario and the ice-fishing capital of Canada. It is also the source of drinking water to 8 municipalities and is under the threat of increased nutrient inputs. To date, primary production has never been measured on Lake Simcoe, and there has been no assessment of the microbial food web. Algae, or phytoplankton, form the base of the food web in lakes and understanding their primary production will determine the possible fish production in the lake. The main objective of this research program is to determine the limiting nutrient(s) to the phytoplankton communities in Lake Simcoe and the differences in primary production. This is being assessed with a thorough, year-round examination of microbial biomass, physiology and metabolism. If we can understand what controls the cycling of C, perhaps we can predict and mitigate the seasonal hypoxia and restore the cold-water fisheries to Lake Simcoe. This program currently involves 7 highly qualified personnel (HQP) including a postdoctoral fellow, 2 masters students, 2 undergraduate summer students and 2 technicians. This application is for four independent pieces of equipment required for the proposed research. The YSI Sonde is a field instrument used to profile the water column of lakes and it was selected due to its use in large lakes such as Simcoe where profiling is needed to deep depths under adverse weather conditions. The Water PAM is a specialized fluorometer used to assess the variable fluorescence of phytoplankton communities in water and is used to examine phytoplankton physiology and provide estimates of production. The isotope analyzer is a specialized, inexpensive and efficient tool to measure stable isotopes. The spectrophotometer will be used to measure dissolved nutrient concentrations in water.