淮河流域农田地区大气CO2浓度变化特征研究
- The characteristics of atmospheric CO2 concentration changes in the Agricultural Areas of the Huai River Basin
- 摘要：为分析淮河流域中下游典型农田区域CO2浓度变化特征，于2023年1~12月在中国气象局淮河流域典型农田生态气象野外科学试验基地铁塔上对95和50m两层高度的大气CO2进行了连续在线观测，并分析了不同高度变化特征、区域输送特征和潜在排放源区.结果表明，该区域CO2日变化四季均呈单峰结构，交通源等人类活动影响较小，夏季50m处日振幅最大，达到了36.3×10-6，而冬季95m处日振幅最小，仅为6.5×10-6，夏季淮河流域农田下垫面植被对CO2浓度影响显著；CO2浓度年变化既受人类活动影响导致冬季最高，也有与北半球同纬度背景浓度春末夏初高特征相似之处，体现了人类活动和自然因素的双重影响； WNW-NW-NNW扇区上游的生产活动在春、秋、冬季三个季节导致该来向CO2浓度相较于季节均值分别升高7.4×10-6、7.6×10-6、5.3×10-6；轨迹分析表明春、秋、冬三季短距离输送是导致CO2浓度升高的主要原因，夏季该区域CO2浓度为（434.4±16.3）×10-6，风速分析和轨迹分析均表明夏季该区域是重要的碳汇区；WPSCF分析显示各季节安徽中南部、苏南浙北均为稳定的潜在贡献源区，秋季豫东、皖北、鲁西南也是潜在贡献源区。
- Abstract：To analyze the characteristics of CO2 concentration changes in typical agricultural areas of the middle and lower reaches of the Huai River Basin, continuous online observations of atmospheric CO2 at heights of 95m and 50m were conducted on the meteorological tower at the typical agricultural ecological meteorological field scientific experimental base of the Huai River Basin, operated by the China Meteorological Administration, from January to December 2023. The study analyzed the variation characteristics at different heights, regional transport characteristics, and potential emission source areas. The results showed that the diurnal variation of CO2 in this area has a single-peak structure in all four seasons, with the largest amplitude in summer at 50m, reaching 36.3×10-6, while in winter at 95m, the daily amplitude is only 6.5×10-6. The annual variation of CO2 concentration is influenced by human activities, leading to the highest levels in winter, and also has a characteristic similar to the background concentration of the same latitude in the Northern Hemisphere, with a secondary peak in late spring and early summer. The production activities upstream in the WNW-NW-NNW sector cause the CO2 concentration in this direction to be 7.4×10-6, 7.6×10-6, and 5.3×10-6 higher than the seasonal average in spring, autumn, and winter, respectively. Trajectory analysis indicates that short-distance transport in spring, autumn, and winter is the main reason for the increase in CO2 concentration. Wind speed analysis and trajectory analysis both suggest that this area is an important carbon sink area in summer. WPSCF analysis shows that the southern part of Anhui and the northern parts of Jiangsu and Zhejiang are stable potential contribution source areas in all seasons, and in autumn, the eastern part of Henan, the northern part of Anhui, and the southwestern part of Shandong are also potential contribution source areas.
