Method Exploring on Dew Condensation Monitoring in Wetland Ecosystem

Dew is a crucial factor of water cycle in wetland ecosystem. This study aims to set up a series of parameters about dew characterization, to build the system of monitoring dewfall and make a model of predicting dew in mire wetland ecosystem. The experiment was in situ carried out during the growing season from mid-May through mid-October in a mire wetland where Carex lasiocarpa is the dominant plant. Dew was measured by using four different kinds of collectors which were glass, poplar woodstick, sunflower stick and filter paper, respectively. Statistical analysis showed that, compared to other collectors, poplar woodstick was the optimal collector for dew measurement considering the ideal surface idiosyncrasy and its convenience for material and operation. Dew began to condense from one and a half hour after sunset and Dew Intensity reached the peak at about half an hour before sunrise. The factual Dewfall in unit field area was calculated by the factors of leaf area index, Dew Days, Dew Intensity, etc. Based on the synchronous meteorological factors, a stepwise linearmulti-variation regression model was established to predict Dew Intensity. Furthermore, the model successfully interpreted the relationship between simulated and measured Dew Intensity. This method which used poplar woodstick, as well as the formula for calculating Dewfall offered a reliable way to analyze dewfall datas in wetland ecosystem, and most importantly, the parameters of dew, which were defined for the first time, provide a more precise way to describe and study dew.