Carbon-nitrogen analyzer to assess elemental dynamics in the environment

碳(C)和氮(N)是生物圈中的关键元素，其丰度因人类活动而发生了显著变化。虽然全球大气中碳的增加得到了广泛的承认，但环境中的氮也有所增加，这改变了初级生产者和异养微生物可获得的碳和氮的平衡。这两种元素与其他生物地球化学重要营养物质，如磷和铁的平衡，也强烈影响水生生态系统中较低的营养水平。例如，环境中碳和氮的相对可获得性的变化可以改变初级生产者的群落组成，并通过改变次级消费者的食物数量和质量而在食物链中连锁。虽然包括C和N在内的多种化学元素的相对有效性的变化越来越多地得到很好的记录，但由于食物网相互作用的复杂性和许多这些影响的上下文依赖性，理解这些变化的生态后果对生态系统生态学家和生物地球化学家来说仍然是一个重要的挑战。研究碳和氮的循环需要测量这些元素在水、气和固体中的形式，因为它们在水生和陆地生态系统中流动。建议的元素分析仪是我的研究项目的核心，该项目检查环境中的C和N的有效性，它们与其他元素的关系，以及它们的生态重要性。请拨经费购买碳-氮分析仪，用于测量干燥的有机样品中的碳和氮，包括藻类、微生物、植物和自然环境中的其他有机物。为此，我将检测环境中的碳和氮，目的是了解营养物质对安大略省湖泊和河流食物网的生态影响。这些数据对于理解低营养水平的食物网动态、对湖泊的长期监测以及这些重要环境的生态系统功能是至关重要的。因此，这种设备对于更好和更知情地管理我们的水产资源，以应对人类对生态系统健康的威胁至关重要。

Carbon (C) and nitrogen (N) are key elements in the biosphere whose abundance has been dramatically altered by human activities. While global increases in atmospheric C are widely acknowledged, N has also increased in the environment, which has altered the balance of C and N available for primary producers and heterotrophic microbes. The balance of these two elements with other biogeochemically important nutrients, such as phosphorus and iron, also strongly affects lower trophic levels in aquatic ecosystems. For example, changes to the relative availability of C and N in the environment can alter community composition of primary producers and cascade through the food web by altering food quantity and quality for secondary consumers. While the changing relative availability of multiple chemical elements, including C and N, is increasingly well documented, understanding the ecological consequences of these changes remains an important challenge to ecosystem ecologists and biogeochemists due to the complexity of food web interactions and the context dependency of many of these effects. Studying C and N cycling requires measuring these elements in aqueous, gas, and solid forms as they flux through both aquatic and terrestrial ecosystems. The proposed elemental analyzer is central to my research program that examines C and N availability in the environment, their relationship to other elements, and their ecological importance. Funding is requested for the purchase of a C-N analyzer, which is used to measure C and N in dried organic samples including algae, microbes, plants and other organic matter from the natural environment. With this, I will examine C and N in the environment with an aim of understanding the ecological effects of nutrients on food webs of lakes and rivers in Ontario. These data are central to understanding food web dynamics of lower trophic levels, long-term monitoring of lakes, and ecosystem function of these important environments. This equipment is thus central to better and more informed management of our aquatic resources in response to human threats to ecosystem health.