关键词: 贺兰山东麓, PM_2.5, 时空分布, 气象因子, 平均风速, 平均温度, 空气相对湿度

Abstract:

Plowing bare farmland is a major source of air pollution in winter and spring in northern China. To clarify the spatial and temporal distribution characteristics and influencing factors of PM_2.5 in Ningxia’s wine grape planting area, and to provide a decision−making basis for air pollution prevention and control, wine grape production units and relevant departments should formulate scientific and reasonable management measures. In this study, the air quality and meteorological monitoring data of 2022 were collected from 9 stations in the grape growing region in the eastern foot of Helan mountain. Spatial interpolation method and correlation analysis methods were used to analyze the spatial and temporal distribution characteristics of PM_2.5 and meteorological influences in this region. The results showed that in 2022, the occurrences of PM_2.5 annual average concentration exceeding 75μg·m⁻³ (level 4) in grape−growing areas such as Bronze gorge ganchengzi meihe winery, Bronze gorge dream shaquan chateau, Bronze gorge west pigeon winery, Helan mountain meihe winery and Pengsheng winery accounted for 13.52%, 10.44%, 6.93%, 6.10% and 6.43% of the occurrences of PM_2.5 concentration at different levels in the whole year, respectively. The annual average concentration of PM_2.5 in non−grape growing region such as Lingwu hedong airport, Dawukou sheyuyuan in Shizuishan and Helan mountain xinxiaolu in Yinchuan exceeded 75μg·m⁻³ (Level 4) accounted for 2.94%, 2.40% and 0.06% of the annual occurrences of different levels of PM_2.5 concentration. The monthly PM_2.5 concentrations at the nine stations were significantly negatively correlated with the average temperature and positively correlated with the relative humidity, without significant test. Only the monthly PM_2.5 concentration of Lingwu hedong airport was significantly negatively correlated with the average wind speed of 2m. It can be seen that the average temperature, a meteorological factor, significantly affects the PM_2.5 concentration, and agronomic operations such as 'spring planting of seedlings and autumn mulching' in the grape base may affect the PM_2.5 concentration by changing the local microenvironment. In order to reduce the release of particulate pollutants, the primary consideration is to reduce the frequency of human disturbance in the grape planting area from January to February, increase the coverage of forest and grass in the grape planting area to reduce the amount of soil wind erosion and the probability of wind erosion, and finally promote the healthy and green sustainable development of the grape planting area.

Key words:

Eastern foothills of Helan mountain, PM_2.5, Spatiotemporal distribution, Meteorological factor, Average wind speed, Average temperature, Relative humidity