From divide to nexus: Interconnected land use and water governance changes shaping risks related to water

Abstract

Land use changes have been recognized to have considerable impacts on water; and vice versa, changes in water use and governance may have implications on land use and governance. This study analyzes recent land use/land cover (LULC) changes, and how changes in land use and water governance are perceived to affect land use and water-related risks in three case-study areas exposed to frequent flooding and inadequate or deteriorating water quality. The areas studied included the Vantaa basin in Finland, a section of the Grijalva basin in Mexico, and the Lower Xe Bang Fai basin in Laos. We show how there are complex and context-specific interrelationships between land use, water governance, and waterrelated risks in each study area. In a remote sensing analysis of LULC changes during the past 30 years, we found that LULC changes have been the most dramatic in Xe Bang Fai, Laos in the form of expanding agriculture and built-up areas; however, there has also been an expansion of built-up areas in the two other sites. According to our stakeholder scenario workshop data, analysis of policy documents and field visits, the nexus between land, water and risks is recognized to some extent in each study area. There have been modest shifts toward more integrated land use and water governance in Vantaa and Grijalva, while the integrated governance seems to have been most absent in Xe Bang Fai. Tighter integration of land and water policies is needed in all the three cases to manage the land use changes in a way that their effects on water-related risks will be minimized.

Role of Transformative Capacity in River Basin Management Transformations

“…Although there are similarities between river basins across the world, a direct comparison is challenging due to context-specficity of historical trends and main drivers of change (cf. Räsänen et al 2017Räsänen et al , 2018.…”

“…The river has a modest average flow of 16 m 3 /s; however, due to small natural capacity to level changes in river flow, the extremes vary considerably. The upper reaches of the basin consist of mainly forest and agricultural land, while increasingly urbanizing areas dominate the southern parts of the basin (Räsänen et al 2018).…”

The spatial component of integrative water resources management: differentiating integration of land and water governance

“…The spatial turn in water management has its repercussions in the common management of land and water. Land use has had impacts on water, but also water governance has influenced land use (Räsänen et al, 2018;van der Brugge, Rotmans, & Loorbach, 2005). Since both land and water are scarce, they need to be properly managed (Hartmann & Spit, 2014).…”

Impact of urban development on the risk of flooding: A case study of Wuhan City, China

“…。 因此， 探究内涝成因机制及其应对策略成为研 究热点 [2][3][4][5] 。影响城市内涝风险的因素可以分为自 然因素和人文因素 [6][7][8] 。自然因素主要包括气候特 征、 降雨量、 土壤性质、 地形地势以及水文气象条件 等。人文因素则包括用地结构、 用地变化、 排水管 网条件、 不透水面分布等 [9][10][11] 。 当前研究主要侧重人文因素， 并已取得较为丰 富的成果。在用地结构方面， 以韩国首尔为案例， Lee 等 [7] 的研究表明： 不透水面和农业用地的成片布 局会加剧内涝灾害程度， 且紧凑高密度的用地布局 一定程度上会阻碍雨水排放。而城市绿地空间在减 缓雨水径流、 降低洪涝风险方面具有重要作用 [12] 。 对城市内涝与土地利用结构和景观格局之间的关 系研究 [13] 亦揭示， 居住等建设用地对内涝灾害影响 最大， 而复杂的景观体系可降低内涝灾害。在用地 变化方面， 彭建等 [14] 指出建设用地的增加对暴雨洪 涝灾害风险具有不可忽视的影响。王玉鑫等 [15] 利 用水文产流模型与经验方程模拟不同土地利用情 景下的城市积水， 发现城市化背景下迅速增加的硬 质用地加剧了内涝风险。Gori 等 [2] [18][19] 。同时， 作为量化城市 化强度和程度的关键要素， 不透水面密度也是重要 影响因素之一 [20] 。不透水面的增加会降低地表下 渗率和储水能力、 增大径流速率， 进而增加内涝渍 水风险 [21][22] [23] 。墨西哥地区的内涝风险研究证实， 湿 地的开发建设将大大增加城市洪涝风险 [4] 。将水域 填占开发为不透水面的城市用地， 将直接造成水网 系统的连接阻塞， 进而引发严重的洪涝灾害。 然而， 在城镇化进程快速推进和城市规划管控 滞后的双重背景下， 中国大部分城市都存在不同程 度的填湖造陆现象 [24][25][26] 。中国学者针对这一现象与 内涝分布的关系进行了研究。李仁东等 [27] 通过水 调节能力估算模型指出， 湖泊面积的减少会极大地 降低区域洪水调蓄能力， 从而提高内涝风险。曾忠 平等 [28]…”