Preliminary study of water temperature changes to identify the hydrological dynamics at Situ Cibuntu

Water temperature is one of the important parameters in the aquatic systems, and it remains as the interesting subject of world-wide environmental research. Water temperature has a vital role in various processes that determine whether an aquatic environment is suitable for fish and other organisms. The objective of this study is to identify the parameters of hydrological, meteorological and topological those influence water temperature and its change at Situ Cibuntu site based on data from April 2008 to April 2009. In addition, the changes in water temperature during rainfall events could identify the mechanism that generates the initial response as direct inputs of rainwater. In order to gain insight on water temperature fluctuations, water temperature data for one year were statistically analyzed using root mean square (Rms) and harmonic methods. From our analysis, the largest of air (Ta) and water temperatures (Tw) were 30.6oC and 30.9oC, respectively. To the contrary, the smallest of those were 21.1oC and 23.0oC, respectively. In addition, the highest values of Rms 7-days for Ta and Tw on September were 1.51 and 1.57, respectively. Next, based on hourly Tw changes during rainfall events, it seemed that subsurface flow influenced water temperature changes. In addition, the management of Situ influenced the flow paths differently through the changes of infiltration rate, surface runoff, interflow/subsurface flow and groundwater percentage. Further, we expect that using Tw could trace the water sources and that it would be good tracer of basin hydrology as easily observable indicator.