关键词: 雅尼湿地, 太阳辐射, 温度, 湿度, 气候特征

Abstract: We analyzed climate characteristics in the Yani wetland by carrying out climate monitoring by a standard automatic weather station in Yani National Wetland Park, Nyingchi City, Tibet Autonomous Region. During the period of 2019 to 2021, annual total radiation of the study area was 7474.25 MJ·m^-2; near ground annual net radiation was 3507.83 MJ·m^-2, with the daily average being greater than 0 MJ·m^-2. Photosynthetically active radiation was 11410.39 mol·m^-2. The total radiation, near ground annual net radiation, and photosynthetically active radiation in summer were 2260.91 MJ·m^-2, 1249.94 MJ·m^-2, and 3483.62 mol·m^-2, respectively. During the study period, annual total radiation was more than 6300 MJ·m^-2. The richness and stability of solar energy resources were at grade A. The average annual near-surface temperature in the wetland area was 10.09 ℃, and the highest temperature was in August with an average value of 17.39 ℃. The average temperature in January was 1.19 ℃. During the observational period, the nearsurface air temperature showed an overall rising trend, with a rate of 0.18 ℃·a^-1. The mean annual precipitation was 470.1 mm, which mainly concentrated in summer. The precipitation was 258.9 mm between June and September and only 15.03 mm in winter (January to February and December). The annual average wind speed was 5.8 m·s^-1, and the maximum daily average wind speed was 7.38 m·s^-1 from January to June. The minimum daily average wind speed was 4.3 m·s^-1 from July to September. South and southwest winds prevailed in the region, accounting for 85.4% of the days of a year. The variation of soil temperature showed a unimodal curve and was relatively stable. The average annual soil temperature of 0-40 cm in depth was 13.38 ℃, and soil heat budget was characterized by heat absorption from mid-February to mid-September, and heat loss from mid-September to mid-February of next year. The oxygen content of air showed a decreasing trend, being less in summer than in winter. The annual average oxygen content of air was 83.5%-87.8%, with a decreasing rate of 2.0%·a^-1. Collectively, the Yani wetland area has strong solar radiation and rich resources of light energy. The high level of heat, rainfall, and wetness indicate that the area is in a sub-humid zone. The annual temperature range increases and the warming and humidifying process appears clearly, which is consistent with the trend of climate change on the Qinghai-Tibet Plateau.

Key words: Yanni wetland, solar radiation, temperature, humidity, climate characteristics