The differences in the air temperature, precipitation, evaporation, and relative humidity between wetlands and nonwetlands were analyzed to investigate the effects of alpine wetlands on regional climate. Meanwhile, the changes in precipitation and surface runoff fluxes before and after the typical wetland degradation were discussed, and the effects of wetland degradation on soil organic carbon were assessed. Correlation and regression analyses were applied to exhibit the relationships between wetland landscape areas and meteorological factors. Our results showed that the cooling effects of wetlands on ambient environment were very obvious, and soil temperature could be higher in the area with less surrounding wetland area. The evaporation capacity and relative humidity in wetlands were higher compared to the surrounding non-wetlands. Precipitation and surface runoff flux decreased due to serious wetland degradation, indicating that wetland degradation or expansion had close relation with regional precipitation. Once peat soils were converted to meadow soils or Aeolian sandy soils, soil organic carbon (SOC) would decline linearly. Correlation and regression analyses showed that there were significant correlations between wetland landscape areas and the annual average air temperature, the average air temperature in growing seasons, and the evaporation in growing seasons ( ). 1. Introduction Wetlands are the important underlying surface types on the earth and have their own radiation, thermal and hydrous properties, which can form unique microclimate with significant cooling and humidifying effects [1, 2]. Changes in wetland landscape patterns due to varying hydrological processes have profound impacts on wetland biodiversity, ecological processes, and the emission of greenhouse gases as well as regional and even global climate [3], which is closely related to wetland function changes such as carbon accumulation and emission (i.e., CO2 and CH4) [4]. Some researchers have presented that wetland drainage (including peatlands) can increase soil respiration [5, 6] and have a significant contribution to the feedback processes of carbon cycle and climate change [7]. Therefore, wetlands play an important role in global warming as a result of the great potential of carbon emission [8]. Zoige Plateau is a hummocky plateau with the highest and largest area of alpine peatland wetlands worldwide. The alpine wetlands on the Zoige Plateau cover approximately 470,000？hm2, where the amount of reserved peats can reach up to 7.6？billion？m3 and become the biggest peat mining
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