Clustering Analysis on the Climatic Conditions in Hundreds of Kilometers of Celery Belts in Hulu River Valley

By using climate data in national stations in Xiji County, Ningxia during 1981 and 2020, a regression analysis was carried out on weather data in crop growth season in three automatic weather stations in Hulu River Valley. The results showed that celery belts of Hulu River Valley was divided into two groups: early-maturing region of south Xinglong-Xiaohe where is warm and rainy, serotinous region of north Jiqiang-Xinying where is warm and cold and rainless. Four subregions: Xinlong, Xiaohe, Jiqiang, Xinying. Each sub-region was divided into five regions according to climate layer and observation in growth season: temperature accumulating planting period, low temperature seedling period, suitable temperature for external leaf growth stage, high-temperature for celery mulching-sanded plantation in different sowing periods, water and fertilizer, insect prevention, time to market sales.