| 引用本文: | 彭宇杰,朱永华,吕海深,等.淮北平原不同时间尺度下的夏玉米干旱特征[J].灌溉排水学报,2024,43(6):76-85. |
| PENG Yujie,ZHU Yonghua,LYU Haishen,et al.淮北平原不同时间尺度下的夏玉米干旱特征[J].灌溉排水学报,2024,43(6):76-85. |
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| 摘要: |
| 【目的】在生长阶段和生长季内起始不定的10 d尺度下，对淮北平原夏玉米的干旱时空特征进行研究，探索不同土层深度下的干旱规律，为夏季作物的抗旱灌溉提供更加科学合理的规划依据。【方法】基于干旱严重程度指数（DSI），将2010—2019年表土层（0~10 cm）和根系主要分布层（0~50 cm）的干旱状态进行分级，并利用M-K检验法和克里金空间插值法，在生长阶段和生长季内起始时间不定的10 d两种较小时间尺度下，对淮北平原夏玉米干旱的时间变化趋势和空间分布特征进行了分析。【结果】①自2016年生长季开始，砀山、蒙城、谯城站的干旱程度和频率显著升高，阜阳站干旱程度和频率都显著降低，而宿州站的干旱事件则集中在2010—2012、2019年生长季；与生长阶段尺度相比，部分干旱事件在生长季内起始不定的10 d尺度下的干旱程度更大，干旱频率也更高；②各个生长阶段的多年平均干旱指数最高的是播种—出苗期，达到了中旱以上，此生长阶段的干旱频率同时也最高，在40%以上；2种尺度下重旱以上的干旱事件常发生在北部砀山和中部蒙城、宿州区域；0~10 cm土层的干旱频率在西南部较高，0~50 cm土层的干旱频率则在东部和北部较高；③生长季内起始不定10 d尺度下，每个生长季干旱程度最高的时段其起始时间多数处于播种—出苗的早期，出苗—拔节的早期，拔节—抽雄的中期，且大都在重旱以上，少数发生在8月与9月。【结论】淮北平原夏玉米在2016年生长季之后有显著的干旱突变趋势，干旱程度和频率常常在播种—出苗期最高，相比于生长阶段时间尺度，在生长季内起始不定的10 d尺度下会识别出更高的干旱程度，干旱频率也有所增大，同时能更确定严重干旱事件的发生时段。 |
| 关键词: 夏玉米；干旱严重程度指数；时间尺度；生长阶段 |
| DOI：10.13522/j.cnki.ggps.2023507 |
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| Spatiotemporal variations in summer maize droughts in the Huaibei Plain |
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PENG Yujie, ZHU Yonghua, LYU Haishen, LU Wen, ZHU Wanting, WANG Yining, WANG Zhenlong
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1. College of Hydrology and Water Resources, Hohai University, Nanjing 210098, China;
2. Nanjing Hydraulic Research Institute, Nanjing 210029, China; 3. Anhui & Huaihe River Institute of Hydraulic Research,
Anhui Provincial Key Laboratory of Water Resources, Hefei 230088, China
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| Abstract: |
| 【Objective】Drought is a significant abiotic stress affecting agricultural production in many regions of China. This study investigates the spatiotemporal variations in drought during the growing seasons of summer maize in the Huaibei Plain.【Method】The analysis was based on the drought severity index (DSI) from 2010 to 2019 calculated using metrological data measured from weather stations across the region. We focused on the top 0-10 cm soil layer and the root zone from the soil surface to the depth of 50 cm. The M-K test and the Kriging spatial interpolation were used to analyze the spatiotemporal variation in droughts over the region at different time scales.【Result】① Since 2016, the severity and frequency of droughts have both significantly increased in the areas of Dangshan, Mengcheng, and Qiaocheng, while decreased in the area of Fuyang. In Suzhou, droughts mainly occurred in 2010—2012 and 2019. Compared to seasonal scale, some drought events exhibited greater severity and higher frequency at the ten-day scale with unpredictable onset. ②The highest average annual drought index and frequency both occurred during the sowing-emergence stage, reaching moderate level or above, with the frequencies exceeding 40%. Severe droughts or worse at both timescales occurred in northern Dangshan and central Mengcheng and Suzhou. The frequency of the 0-10 cm soil-layer droughts was higher in the southwest, while the frequency of 0-50 cm soil-layer droughts was higher in the east and north than in other areas. ③ At the ten-day scale, the periods with the highest drought severity in each growing season mostly started in the early stage of sowing - emergence, emergence - jointing, and the mid-stage of jointing - tasseling. Severe droughts occurred primarily in August and September.【Conclusion】Since 2016, there has been a significant increase in drought severity and frequency for summer maize in the Huaibei Plain, particularly during the sowing seedling stage. Severe droughts were observed at uncertain ten-day scales, with increased drought frequency. |
| Key words: summer corn; comprehensive drought index; time scale; growth stage |
