Catchment hydrology and the stream environment

水体温度是影响水生生态系统最重要的物理因素之一。它直接控制物种分布，以及生物、生化和化学过程的速率。河流温度反映了气象和水文过程的相互作用，河流温度模式可受到土地利用和气候变率和变化的影响。以前的许多研究都集中在气象对河流温度的控制上，但最近的研究表明，水文过程是重要的。本研究的目的是提高我们对河流温度的水文控制的认识，为预测未来气候变化、土地利用和冰川消退的影响提供更完整的依据。实地研究将使用热预算方法来检查在采伐和未采伐地区陡峭的源头溪流中跨河床和河岸的水交换的作用，以评估其相对于其他过程的重要性。此外，还将评估小而陡的溪流中常见的水池的影响。地下水对河流温度模式的影响将通过比较主要在地下水排放影响方面不同的河流的两个部分的热收支来评估。实地工作还将侧重于冰川下游的河流温度变化与天气和河流流量变化的关系。

Stream temperature is one of the most important physical factors influencing aquatic ecosystems. It directly controls species distribution, as well as rates of biological, biochemical and chemical processes. Stream temperatures reflect the interacting effects of meteorological and hydrologic processes, and stream temperature patterns can be influenced by land use and climatic variability and change. Much previous research has focused on the meteorological controls on stream temperature, but recent studies have shown that hydrologic processes are important. The objective of this research is to improve our understanding of the hydrologic controls on stream temperature to provide a more complete basis for predicting the effects of future climate change, land use and glacier recession. Field studies will  use a heat budget approach to examine the roles of water exchanges across the stream bed and banks in steep headwater streams in logged and unlogged areas to evaluate their importance relative to other processes. In addition, the effects of pools, which are common features in small, steep streams, will be evaluated. The effects of groundwater on stream temperature patterns will be assessed by comparing the heat budgets of two sections of a stream that differ mainly in terms of the influence of groundwater discharge. Field work will also focus on stream temperature variability downstream of glaciers in relation to variations in weather and stream discharge.