Error Assessment for Height Above the Nearest Drainage Inundation Mapping

Real‐time flood inundation mapping is vital for emergency response to help protect life and property. Inundation mapping transforms rainfall forecasts into meaningful spatial information that can be utilized before, during, and after disasters. While inundation mapping has traditionally been conducted on a local scale, automated algorithms using topography data can be utilized to efficiently produce flood maps across the continental scale. The Height Above the Nearest Drainage method can be used in conjunction with synthetic rating curves (SRCs) to produce inundation maps, but the performance of these inundation maps needs to be assessed. Here we assess the accuracy of the SRCs and calculate statistics for comparing the SRCs to rating curves obtained from hydrodynamic models calibrated against observed stage heights. We find SRCs are accurate enough for large‐scale approximate inundation mapping while not as accurate when assessing individual reaches or cross sections. We investigate the effect of terrain and channel characteristics and observe reach length and slope predict divergence between the two types of rating curves, and SRCs perform poorly for short reaches with extreme slope values. We propose an approach to recalculate the slope in Manning’s equation as the weighted average over a minimum distance and assess accuracy for a range of moving window lengths.     

天堂河河道治理工程水质改善预测分析

河道治理工程重在改善河道的水质,以恢复河流生态系统。本文以北京市大兴区天堂河河道治理工程为例,介绍了河道治理工程环境影响评价中的水质改善预测分析,首先分析生态需水量和供氧量是否满足河流生态需水要求,后又利用地面水环评助手软件预测了河流水质,预测分析了天堂河水质目标的可达性,旨在为以后的河道治理类工程环境影响评价提供参考。     

建筑小区的海绵化改造效益核算——以固原市玫瑰苑小区为例

以固原市玫瑰苑小区为例,根据小区可改造绿地空间充足、雨落管断接改造难度较小等特点,提出了海绵化改造思路及工程内容,并对海绵化改造后的经济效益和生态效益进行核算。结果表明:通过海绵化改造即改造排水系统,建设下沉式绿地、植草沟、雨水花园、雨水罐、蓄水池、透水铺装等措施,可使小区综合雨量径流系数降低0.21,小区雨水径流量减少5 137.85 m ³∕a,具有良好的雨水调蓄效益;海绵化改造后具有一定的经济效益,可节约城市排水设施费用411.03元∕a,节约自来水费用4 159.20元∕a,节水效益达28 155.42元∕a;海绵化改造后可吸碳8.18 t∕a,释放氧气6.31 t∕a,吸收二氧化硫50.73 kg∕a,生态环境效益显著。     

我国华北地区城市水生态环境现状分析及综合整治对策

从水环境、水资源和水生态3个方面解析了我国华北片区城市水生态环境问题的内在因素。结果表明,区域城市生活污水排放量大,污水收集与处理设施仍存在短板;钢铁、制药、石化行业污染问题突出,特别是山东省和京津冀城市群;季节性降雨引起的城市面源污染不容忽视;城市水生态系统受损严重,水域面积大幅萎缩,河湖岸带破坏严重,富营养化进程加剧,生物多样性下降;城市水资源极度匮乏,水资源开发利用强度大,用水浪费严重,河流干涸断流问题突出。针对上述问题,提出了区域城市近期 (2021—2025年) 、中期 (2026—2030年) 和远期 (2031—2035年) 分阶段的城市水生态环境质量提升目标和综合整治对策建议。本研究结果可为同类北方城市解决水生态环境问题提供参考。     

Parks versus PES: Evaluating direct and incentive-based land conservation in Mexico

Protected areas (PAs) and payments for ecosystem services (PES) are the top two mechanisms available for countries to achieve international REDD agreements, yet there are few empirical comparisons of their effects. We estimate the impacts of PAs and PES on forest conservation, poverty reduction, and population change at the locality level in Mexico in the 2000s. Both policies conserved forest, generating an approximately 20–25% reduction in expected forest cover loss. PES created statistically significant but small poverty alleviation while PAs had overall neutral impacts on livelihoods. Estimates by individual policy type for the same level of deforestation risk indicate that biosphere reserves and PES balanced conservation and livelihood goals better than strict protected areas or mixed-use areas. This suggests that both direct and incentive-based instruments can be effective, and that policies combining sustainable financing, flexible zoning, and recognition of local economic goals are more likely to achieve conservation without harming livelihoods.     

论流域水质与水量集成规划

“水量”与“水质”是流域大系统的两个特征,水环境研究偏重于水质,而水资源研究则更偏重水量,但是“质”与“量”是不能截然分开的,它们之间既相互关联,又互影响,相互制约,构成矛盾的统一体,基于这一出发点,本文从规划方法学的历史发展与流域水环境大系统的结构分析入手,系统阐述了提出流域水质与水量集成规划基本概念,目标及其策略与技术路线。     

中国区域环境绩效及波特假说的再检验

以二氧化碳为非期望产出,基于序列DEA的方向性距离函数、环境规制强度指数、Malmqulist-Luenberger指数,测度了1999~2010年中国30个省、市、自治区及东、中、西、东北四大区域的环境技术效率、环境规制成本及全要素生产率,并对四大区域的全要素生产率进行了波特假说的再检验.研究结果表明:区域间的环境技术效率呈现东-东北-中-西依次递减的演变格局;东北老工业基地的环境规制成本最高、西部地区最低;环境规制强度与全国及四大区域全要素生产率有显著的正相关性,这支持了波特假说的存在;技术进步效应的检验结果显示,只有中部区域支持波特假说的存在,西部区域检验结果表明碳排放的规制过高会对技术进步带来消极影响;环境技术效率变化效应的检验结果显示,全国及四大区域均支持波特假说的存在,碳排放规制强度的加强,会推动各地区在不同时期追赶最优生产前沿面的程度.     

飞机环控系统典型故障分析

环控系统解决了飞机座舱的供气、调温和增压问题,座舱的压力制度按3个阶段进行。通过典型的飞机环控系统故障,对座舱压力调节机理进行了分析,介绍了座舱压力调节过程,分析了导致飞行员耳膜疼痛、座舱压力持续下降的原因,提出了预防故障发生的建议。     

Elementary Structural Units of the Biosphere

Russian Journal of Ecology -     

浅谈我国冰雹的分布规律及其保险对策

本文从冰雹灾害的分布规律着手,研究我国雹灾对策形式之一——雹灾保险,在对世界各国雹灾保险借鉴的基础上,选择我国雹灾保险的模式,建立适合我国国情的雹灾保险。