During the last decade, surface groundwater connectivity has become a major issue for water resources management in NSW. Consequently, as part of this PhD study, I have applied heat an environmental tracer to study infiltration/exfiltration in two contrasting hydro-geomorphological environments in NSW, Australia (Peel, Cockburn and Gunnedah sites in the Namoi Catchment, and Baldry and Sloans sites in the Central West Catchment). In the context of this thesis, the hydrological processes targeted of relevance to water resources management are grouped into three main issues listed below: 1. Delineation gaining and losing reaches within the study area using heat as an environmental tracer; 2. Inference of the dynamic nature of stream bed conductance from a thermal stream bed data; 3. Importance the issue of scale in surface/groundwater connectivity studies
