Potential of retrofitted urban green infrastructure to reduce runoff - A model implementation with site-specific constraints at neighborhood scale

The urbanization has resulted in significant changes in the water balance. Urban Green Infrastructures (UGI) have become a promising method for reducing reoccurring floods whilst providing additional social and ecological benefits. However, there are several challenges to successfully implementing UGI in already developed areas, such as accounting for retrofitting UGI scenarios and pre-existing use of spaces. Accurate estimations of the potential of UGI in reducing flood-causing at the watershed scale are therefore important. This study investigates the influence of site-specific constraints on the effectiveness of UGI in reducing flood-causing runoff at the watershed scale. In particular, this study takes urban fabric characteristics in the development of UGI implementation strategies for different types of residential and industrial neighborhoods into account. Furthermore, it applies a hydrological simulation-based approach to estimate the runoff reduction potential of these strategies for a case study in the Metropolitan Area of San José, Costa Rica. The results indicate that UGI implementation potential depends on urban fabric characteristics and modelling different UGI implementation scenarios shows differing hydrological performance. In residential areas, either permeable pavement or infiltration trenches and street planters lead to the highest runoff reduction. In industrial areas, only permeable pavements lead to the highest runoff reduction. Overall, industrial areas enable more potential for UGI and reduce runoff generation. The findings of this study can guide the development of retrofitting UGI scenarios and upscaling strategies under heterogeneous settlement characteristics.     

洪涝风险胁迫下登封市蓝绿基础设施网络构建研究

为提高城市生态防洪韧性，构建蓝绿基础设施网络，依据登封市2021年4月Landsat遥感影像数据，通过降雨-径流水文模型分析枯水月、平水月以及丰水月的淹没范围，并将分析结果转化为电阻面纳入潜在生态廊道的识别与构建中，利用连通性分析和电路理论筛选匹配登封市的最佳扩散距离和廊道“宽度”,并综合分析廊道关键障碍点、夹点以及易涝区现状条件，提出了登封市蓝绿基础设施网络的构建策略。结果表明：1)14个汇水区内的林地在枯水月、平水月以及丰水月的平均雨洪消减率逐渐降低，分别为94.42%、80.85%、47.46%;2)在丰水月随着雨量增加林地逐渐成为在建设用地之下的第二大产流体，导致9.10 km²的建设用地处于淹没风险区。位于洪涝高压区的告城镇受淹面积由枯水月的0.29 km²扩大至丰水月的3.13 km²。3)识别出26个重要源地、4个一般源地、56条潜在廊道、107处关键障碍点以及14处重要夹点。其中登封市东南地区关键廊道较窄且电流密度较高，多处重要夹点毗邻建设用地，且每条廊道均存在多个关键障碍点，多为城镇建筑、交通道路及废弃...     

脱贫地区农村人居环境现状及整治框架——以重庆某县为例

为明确脱贫地区农村人居环境整治思路，本研究通过国家农村人居环境政策演变的梳理和典型县域农村人居环境整治现状的问卷调研，探讨脱贫地区农村人居环境整治框架。结果表明，2004年以来，历年中央一号文件分阶段强调农村基础设施建设、村庄环境整治和农村人居环境整治工作。调查县农业废弃物中农膜和棚膜未回收的村庄占比为29.33%和22.51%，但秸秆和畜禽粪便资源化利用程度较高；公共厕所、污水处理等基础设施的村庄普及率相对较低，农户院落闲置率和倒塌率分别为21.93%和13.28%，倒闭的种养企业厂房废弃率较高，农户卫生厕所普及率仅为57.44%。在脱贫攻坚与乡村振兴衔接期，农村人居环境整治工作应着力促进政府“自上而下”决策和社会组织及农户“自下而上”参与的有机结合，加强农户层面的卫生设施配套、移风易俗推进和环保意识提升等。     

Infrastructure and politics: Why the Belt and Road Initiative proceeded differently in Malaysia and Indonesia

The article seeks to understand the different types and sources of politicisation as well as the consequences for Belt and Road Initiative infrastructure projects. It is argued that while the personalised insulated type of foreign policymaking is conducive to intra-system politicisation, the institutionalised responsive type is associated with extra-system politicisation. While the former type is contingent on political turnovers and brings about abrupt shocks, the latter oftentimes generates societal pushback from socio-economic groups. The article focuses on two flagship Belt and Road Initiative infrastructure projects in Malaysia and Indonesia. Based on fieldwork interviews and process tracing, the article finds that the East Coast Rail Link project in Malaysia has suffered from high risk of political interruption owing to Malaysia's personalised insulated type of foreign policymaking, whereas the Jakarta–Bandung High Speed Rail project in Indonesia has encountered sustained obstacles from Indonesian society and brought about substantial delays under Indonesia's institutionalised responsive type.