Department of Environmental Engineering, National Ilan University, No. 1, Sec. 1, Shennong Rd., Yilan City, Yilan County, 26047, Taiwan.
Environ Sci Pollut Res Int. 2020 Apr;27(11):12725-12745. doi: 10.1007/s11356-020-07656-0. Epub 2020 Feb 1.
Yilan is the main agricultural production area of northern Taiwan, and most of the freshwater in this area is used for the irrigation of rice; however, this area lacks lakes and reservoirs for reserving and balancing supply and demand of surface water. Accordingly, the abundance of groundwater in Yilan plays a crucial role for water supplying. This case study aims to disclose the hidden and potential crisis ignored in Yilan area on its water resources by the water footprint (WF) approach, which consists of blue, green, and grey water-use components; meanwhile, three essential climatic factors temperature, rainfall, and sunshine hours are discussed for examining and identifying their influences. This study adaptively modified a top-down scheme initiated by Hoekstra and Hung 2002, Hoekstra 2003) to properly make estimations of the WF on the basis of current data situation and local condition of this case study area. The quantitative analysis results show that the total average order of magnitude of the WF of rice in Yilan was approximately estimated to around 8000 m t, which has a comparative disadvantage and is around six times as many as the estimation on average of global, on a decadal basis after the millennium. Notably, it reveals an extravagant water-using attitude and a situation of oversupply in Yilan since this area tends to suppose water supply from the groundwater is abundant and unlimited. In addition, the blue and green water-use components over the crop period are directly and evidently influenced by rainfall, sunshine hours, and temperature. The grey water-use component will inevitably lead a catastrophic impact due to an excessive utilization of chemicals, fertilizers, and pesticides, in case the temperature keeps rising as a result of global warming and extreme weather conditions caused by the climate change. The potential challenges of freshwater resources and an inefficient as well as a carefree water-using attitude in this case study have been proved to drive the risk and need to take strategic precautions because of the gradually rising temperature, sunshine hours, and declining of the normal rainfall.
宜兰是台湾北部主要的农业生产区，该地区的大部分淡水用于灌溉水稻；然而，该地区缺乏湖泊和水库来储存和平衡地表水的供需。因此，宜兰丰富的地下水在供水方面起着至关重要的作用。本案例研究旨在通过水足迹（WF）方法揭示宜兰地区水资源中被忽视的隐藏和潜在危机，该方法由蓝、绿、灰三种用水成分组成；同时，讨论了三个基本气候因素，即温度、降雨量和日照时数，以检查和识别它们的影响。本研究适应性地修改了 Hoekstra 和 Hung（2002 年，Hoekstra 2003 年）提出的自上而下的方案，以便根据本案例研究地区的当前数据情况和当地条件，对 WF 进行适当的估计。定量分析结果表明，宜兰水稻的 WF 总量平均约为 8000 万立方米，在千年后，与全球平均水平相比，具有相对劣势，约为全球平均水平的六倍。值得注意的是，这揭示了宜兰地区挥霍用水的态度和供过于求的情况，因为该地区倾向于假设地下水供应丰富且无限。此外，在作物生长期间，蓝水和绿水的使用量直接受到降雨量、日照时数和温度的影响。由于全球变暖以及气候变化引起的极端天气条件导致的温度持续上升，灰水的使用量将不可避免地导致过度使用化学品、化肥和农药而产生灾难性的影响。如果气温持续上升，淡水资源的潜在挑战以及这种情况下低效和无忧无虑的用水态度将被证明会带来风险，需要采取战略预防措施，同时正常降雨量减少。
