Cooling effects of different wetlands in semi-arid rural region of Northeast China

Wetland ecosystems play an important role in regulating local and regional climates through evaporative cooling effects that affect the exchange of energy and water with atmosphere. A lot of researches had been focused on the wetland cooling effect, especially in mitigating urban heat island effect. However, the intensity and influencing factors of wetland cooling effect currently cannot be thorough explained. In this study, we assessed the cooling effect of wetlands with different types in rural area of Northeast China by using split-window algorithm (SWA) to estimate land surface temperatures (LST) from Landsat-8 thermal infrared sensor. We used correlation analysis to examine the relationships between characteristics of wetlands and cooling effect. Our results showed that paddy fields had the largest cooling effects than lakes followed by marshes for human disturbance. Size and shaped complexity were important characteristics to determine wetland cooling effects. Although our results suggested that larger size of wetlands might have higher intensity and spatial extent of cooling effects, small size of wetlands might have large or almost similar amount of cooling effects with the larger ones. Our findings have important implications for land managers and policy makers to design effective plans for conservation and climate change adaptation.