绿水的多角度评估及其在碧流河上游地区的应用

Assessment of Green Water from Multi-angle View at catchment Scale

综述了现有的绿水评估研究状况,并针对现有绿水研究中缺乏小尺度评估方法等问题,使用SWAT水文模型在小尺度建立了多角度评估绿水(包括绿水量的静态估算、绿水的时空分布估算和气候变化条件下的绿水估算)的方法。以碧流河上游地区为例,用此方法估算了绿水量,研究了绿水时空分布规律以及气候变化条件下绿水的响应情况。研究结果表明:①在研究区,绿水是水资源的最大组成部分,在绿水成分中绿水流是主要部分;②从时间角度看,全年中除了8月,绿水占优;③从空间角度看,绿水主要集中在主河道附近地区;④不同气候变化情景下,绿水流量变化差异显著。基于SWAT水文模型模拟建立的绿水多角度评估方法,是引入绿水概念后进行小尺度绿水评估研究的切实可行的办法,值得在中国推广使用。

Being disregarded in traditional water resources research, Green Water has been a subject of great interest in recent years in the world. First, the concept of green water was introduced. Second, methods of assessing green water were summarized, revealing that most green water assessing methods only focus on a large scale, which lack for precision. Last, by using a SWAT （Soil and Water Assessment Tool） hydrological model, a new method to assess green water from various angles on a small scale is introduced with a case study in a 1 328 km^2 river basin in Northeastern China. The basic volume of green water, temporal and spatial distributions and green water varieties affected by climate changes are analyzed with this method. All the results prove that it is a reasonable method to assess green water on small scale based on the SWAT model and this method is worth popularizing in China. Meanwhile, this method can provide solid research foundation for water resources management. As a result, the volume of green water is higher than that of blue water and the volume of green water flow is higher than that of green water storage in study area. In temporal study, the volume of green water is dominant during the whole year except August. Green water storage is dominant in winter while green water flow is dominant in other seasons. In spatial study, green water mainly distributes around arterial river area, while blue water mainly distributes in the eastern, north-western and southern parts of Biliu basin. In varied climate change scenarios, the volume of green water flow changed remarkably. The volume of green water flow increases with the growth of precipitation and temperature. The influence of precipitation upon green water flow is stronger than that of temperature. The influence of temperature on the green water flow changes obviously with the increase of precipitation. By modifying the SWAT model manually, we found a major limitation that there was no output of productive part and non-productive part of green water flow in the parameters of the SWAT model.