The temporal-spatial variation of water resources constraint on urbanization in the northwestern China: examples from the Gansu section of west Longhai–Lanxin economic zone

Urban Development with the Constraint of Water Resources: A Case Study of Gansu Section of Western Longhai-Lanxin Economic Zone

“…Wuwei city, one of the Inland River (Shiyang River) cities, has been increasing its proportion of water left for the eco-environmental system through large national and local efforts on the reasonable use of water. But compared to the international alert level of 40% water resources development (i.e., 60% of water remains for the ecosystem), all nine cities of the Gansu section should return more water from the socioeconomic system to the ecosystem [7].…”

“…In particular, Lanzhou, the capital city of Gansu province, belongs to the relatively strong constraint-high type, four cities including Jiuquan, Jiayuguan, Jinchang and Tianshui, belong to the intensive constraint-high type, and the remaining four cities, including Zhangye, Wuwei, Baiyin and Dxingxi, belong to the extreme constraint-low type. These results show that the Gansu section will continue to be affected by water resources constraint on urbanization and local economic development for some time to come [7].…”

“…Especially in the twenty-first century, less than 70% of the water resources have been developed, although this level is still much higher than the international alert level of 40%. At the same time it can be seen that the rise in the Gansu section's F w is clearly smaller than that of its F u , so that the relative constraint of water resources on urbanization has not declined, and water resources management will become increasingly difficult if this trend is not reversed [7].…”

“…The model for the comprehensive measurement of water resources constraint on urbanization is built upon the integrated indicator system of water resources and urbanization, using the entropy technique of supported analytic hierarchy process (AHP) to calculate the weight of indicators at all levels, using a fuzzy membership function model to calculate the specific membership values of each indicator, the weighted average method to individually calculate the integrated indexes of water resource development potential and the indexes of urban synthesized development, and then using these to calculate the water resources constraints on urbanization, and grade their intensity accordingly [7][8][9].…”

“…There are, however, obvious differences among the WRCIs of the nine cities of the Gansu section, reflecting variations in the WRCIs. Specifically, the situations in these nine cities over this period have been: Lanzhou changed from intensive constraint to relatively strong constraint, with a significant decline in its WRCI; five cities changed from extreme constraint to intensive constraint, including Wuwei and Jiuquan with significant declines in their WRCI, Jiayuguan and Jinchang with no dramatic declines and Dingxi with a fluctuating decline; three cities remained at the same level of water resource constraint, including Zhangye and Baiyin with extreme constraint, and Tianshui with intensive constraint [7].…”