Ma Xiaolei, Jiao Shixing
School of Resource Environment and Tourism, Anyang Normal University, Anyang, 455000, Henan, China.
Environ Sci Pollut Res Int. 2023 Jan;30(1):2086-2102. doi: 10.1007/s11356-022-22139-0. Epub 2022 Aug 5.
Agriculture is the largest freshwater consumer, accounting for ~ 70% of global freshwater consumption. The agricultural water footprint (WF) and water resources ecological footprint (EF) are used to describe the ecological environment and socioeconomic functions of water resources. Anyang in the North China Plain is a typical area with freshwater shortage and was selected as a study area to estimate water consumption by agriculture. We estimated the spatiotemporal variation of green, blue, and grey WF of five crops in Anyang during 1990-2018 based on the WF theory, EF, and water resources carrying capacity (EC) methods. To analyze the EF of specific crops, we developed the framework between agricultural WF and EF, and quantified the EF of specific crops. The results show that the WF, WF, and WF of Anyang increased from 1188, 1560, and 511 million m in 1990 to 1440, 1736, and 1010 million m in 2018, respectively, mainly owing to the increase of cultivated area and amount of agricultural nitrogen. Winter wheat and maize were the two leading crops in both green and blue water consumption, taking 31.35 and 55.25% of the total WF, and 71.32 and 22.52% of the total WF, respectively. The average unit mass WF and WF of crops showed a reducing trend during 1990-2018 because of the urbanization of farmland and the increase of crop yields. Both EC and water ecological deficit per capital in Anyang decreased. Anyang has been in a state of water ecological deficit since 2000. The results imply that Anyang has been importing a large amount of water from other areas for its consumption since 2000. This study is expected to contribute to agricultural water management by providing suitable information to policy-makers. Furthermore, the results of this study indicate that it is urgent to make strict water resource management and water pollution prevention measures to improve the water use efficiency in Anyang and to ease the pressure on water scarcity.
农业是最大的淡水消费领域，占全球淡水消费量的约70%。农业水足迹（WF）和水资源生态足迹（EF）用于描述水资源的生态环境和社会经济功能。华北平原的安阳是典型的淡水短缺地区，被选为研究区域以估算农业用水量。基于水足迹理论、生态足迹和水资源承载能力（EC）方法，我们估算了1990 - 2018年期间安阳五种作物的绿色、蓝色和灰色水足迹的时空变化。为分析特定作物的生态足迹，我们构建了农业水足迹与生态足迹之间的框架，并对特定作物的生态足迹进行了量化。结果表明，安阳的绿水足迹、蓝水足迹和灰水足迹分别从1990年的11.88亿立方米、15.60亿立方米和5.11亿立方米增加到2018年的14.40亿立方米、17.36亿立方米和10.10亿立方米，主要原因是耕地面积和农业氮肥用量的增加。冬小麦和玉米是绿色和蓝色水消费的两大主要作物，分别占总水足迹的31.35%和55.25%，以及总蓝水足迹的71.32%和22.52%。1990 - 2018年期间，作物的平均单位质量水足迹和蓝水足迹呈下降趋势，这是由于农田城市化和作物产量增加所致。安阳的水资源承载能力和人均水生态赤字均有所下降。自2000年以来，安阳一直处于水生态赤字状态。结果表明，自2000年以来，安阳一直在从其他地区调入大量水资源以供消费。本研究有望通过向政策制定者提供合适信息，为农业水资源管理做出贡献。此外，本研究结果表明，迫切需要制定严格的水资源管理和水污染防治措施，以提高安阳的用水效率，缓解水资源短缺压力。
