| 引用本文: | 蒋博武,孟 丹,郭晓彤,等.基于Landsat-8遥感数据的冬小麦种植区地表蒸散量时空分布研究[J].灌溉排水学报,2022,41(7):140-146. |
| JIANG Bowu,MENG Dan,GUO Xiaotong,et al.基于Landsat-8遥感数据的冬小麦种植区地表蒸散量时空分布研究[J].灌溉排水学报,2022,41(7):140-146. |
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| 摘要: |
| 【目的】基于Landsat-8遥感数据估算冬小麦不同生育期蒸散量，为区域尺度科学、精准灌溉提供依据。【方法】以河南省商丘市梁园区为研究区，选取Landsat-8遥感数据、气象数据和冬小麦农业观测站点数据，利用监督分类结合阈值法提取冬小麦种植区的空间分布，采用SEBS模型估算其蒸散量，分析冬小麦蒸散量的时空变化特征。【结果】研究区内冬小麦种植面积的提取精度为88.0%，kappa系数达到了0.75，冬小麦种植面积占研究区耕地总面积的66.85%，占土地总面积的43.96%。冬小麦蒸散量随季节变化显著，平均蒸散量表现为夏季＞春季＞秋季＞冬季。分析不同生育期冬小麦蒸散频率，在播种期、分蘖期、拔节期和抽穗期的蒸散频率分布集中，在收获期蒸散频数分布离散,冬小麦蒸散量表现为：抽穗期＞拔节期＞收获期＞播种期＞分蘖期。【结论】基于Landsat-8遥感数据，采用SEBS模型可准确估算冬小麦日尺度蒸散量的时空分布，研究结果对于农业水资源合理利用和分配具有重要意义。 |
| 关键词: Landsat-8；SEBS模型；蒸散发；冬小麦 |
| DOI：10.13522/j.cnki.ggps.2021528 |
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| Calculating Spatiotemporal Distribution of Evapotranspiration of Winter Wheat Using the Landsat-8 imageries |
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JIANG Bowu, MENG Dan, GUO Xiaotong, ZHU Lin
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1. College of Resources Environment and Tourism, Capital Normal University, Beijing 100048, China;
2. Beijing Laboratory of Water Resources Security, Beijing 100048, China
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| Abstract: |
| 【Objective】Evapotranspiration is not only an important hydrological process but also a key parameter in irrigation management. Understanding its spatiotemporal variation at regional or catchment scales is essential to improving water resource management and sustaining agricultural production. This paper aims to present a method using air-born imageries to estimate variation in evapotranspiration of winter wheat field. 【Method】The region we studied is Liangyuan District at Shangqiu City, Henan Province. From the Landsat-8 imageries, we extracted the planting areas of winter wheat using the supervision classification method combined with the threshold method. The evapotranspiration was estimate by the surface energy balance system (SEBS) model, from which we analyzed the spatiotemporal variation in the evapotranspiration. 【Result】Compared with ground-truth data, the overall accuracy of the extracted winter-wheat planting areas was 88.0%, with its associated Kappa coefficient being 0.75. Winter wheat accounted for 66.85% of the cropland land and 43.96% of the total land in the studied region. The evapotranspiration varied seasonally, with the seasonal average decreasing from summer to winter. The evapotranspiration varied as the crop grew, with crop demand for water increasing during the sowing, tillering, jointing, and heading stages, while decreasing during the harvesting stage. Overall, the magnitude of the evapotranspiration at different stages is ranked in the following descending order: heading stage > jointing stage > harvest stage > sowing stage > tillering stage. 【Conclusion】The Landsat 8 imagery can be used to estimate daily evapotranspiration from winter wheat field at regional and catchment scales, helping improve irrigation and water resource management. |
| Key words: Landsat-8; SEBS; evapotranspiration; winter wheat |
