Coping with water scarcity in Kashafroud G-WADI Basin,Iran: climate change or growing demands?

This paper assesses the various factors contributing to climate change in the region of the Kashafroud G-WADI Basin in Iran; quantifies the local impacts of climate change, especially local water scarcity; and simulates and discusses several proposed methods to combat these impacts. Hydrologic and climatic data are statistically analyzed and VENSIM modeling is used for various simulations of water resources in the basin. Results show that the natural climate changes affecting Kashafroud Basin include increased temperature, less rainfall, more frequent droughts, and changes in rainfall patterns, all of which are local symptoms of climate change in recent years. However, the most important challenge in the basin is the overexploitation of surface and groundwater resources to meet the growing water demands, especially domestic needs. Changes in land use, reallocation of water uses, groundwater depletion, and degradation of the quality of surface waters have all contributed to significant changes in the environmental features of this basin, and are the main reason why water demands now exceed the renewal capacity of the basin. Proposed response measures include reallocation of resources among different uses, inter-basin water transfers, drawing water from six small dams on the Kashafroud River, reducing groundwater extraction, and replacing groundwater extraction for agriculture by reuse of urban wastewater. This study concludes that although changes in global climatic parameters have altered environmental features in the basin, local factors, such as water utilization beyond the renewable capacity of the basin, are more significant in worsening the impacts of climate change.     

日本绿色乡村旅游发展综述及农业遗产地绿色乡村旅游模式的初步探讨（英文）

众多研究认为可持续旅游(Sustainable Tourism)可在平衡保护环境和开发农业遗产地双方利益方面起到关键作用。能登里山里海景观作为日本传统农村景观的一个缩影,在2011年被认定为"全球重要农业文化遗产(GIAHS)"在日本最早的试点地之一。本文先通过分析文献总结了二十几年以来日本绿色乡村旅游发展的历史和现状,并结合农业文化遗产项目的发展目标讨论了在农业遗产地发展绿色乡村旅游的问题和新的机遇。本文以能登半岛一个由农民自发组织运营的农家民宿组织"春兰的故里"作为案例分析。主要的研究问题包括:如何充分利用国际项目来开发日本的绿色乡村旅游;如何在注重经济收入的同时兼顾生态农业的可持续开发?本文采用的研究方法包括文献的分析并多次采访了民宿主人。本研究成果亦提供在偏远地区发展绿色乡村旅游的思路。     

Hydrological model for urban catchments – analytical development using copulas and numerical solution

Abstract

A model based on analytical development and numerical solution is presented for estimating the cumulative distribution function (cdf) of the runoff volume and peak discharge rate of urban floods using the joint probability density function (pdf) of rainfall volume and duration together with information about the catchment's physical characteristics. The joint pdf of rainfall event volume and duration is derived using the theory of copulas. Four families of Archimedean copulas are tested in order to select the most appropriate to reproduce the dependence structure of those variables. Frequency distributions of runoff event volume and peak discharge rate are obtained following the derived probability distribution theory, using the functional relationship given by the rainfall–runoff process. The model is tested in two urban catchments located in the cities of Chillán and Santiago, Chile. The results are compared with the outcomes of continuous simulation in the Storm Water Management Model (SWMM) and with those from another analytical model that assumes storm event duration and volume to be statistically independent exponentially distributed variables.

Citation Zegpi, M. & Fernández, B. (2010) Hydrological model for urban catchments – analytical development using copulas and numerical solution. Hydrol. Sci. J. 55(7), 1123–1136.     

Quantifying the impact of urban area expansion on groundwater recharge and surface runoff

ABSTRACT

In this surface water modelling study, a new spatial evaluation for assessing the impact of urbanization was applied for the semi-arid watersheds intersecting with the Gaza coastal aquifer. The SWAT model was calibrated and validated in a semi-automated approach for streamflow in the main watersheds. The results show that the model could simulate water budget components adequately within the complex semi-arid watersheds. Linear relationships between the change in urban area and the corresponding change in surface runoff or percolation were concluded for the urbanized sub-basins. The urban-surface runoff index (USI) and the urban-percolation index (UPI) were developed to represent a micro-level evaluation of different urban change scenarios in the sub-basins. The global urban-surface runoff index (GUSI) and the global urban-percolation index (GUPI) were derived as macro-level factors reflecting the influence on the overall Gaza coastal aquifer due to urban area expansion.

Editor D. Koutsoyiannis Associate editor E. Rozos     

Statistical interpretation of the daily variation of urban water consumption in Beijing,China

Abstract

The efficient planning and design of water networks, as well as the management and strategies of existing water supply systems, require accurate short-term water demand forecasts. In this study, a statistical model for the estimation of daily urban water consumption was developed. The model was applied to analyse and forecast the daily water consumption in the main district of Beijing, China, from 2006 to 2010. The model exhibited good performance with a coefficient of determination, R², greater than 0.9 in both the calibration and validation periods. The results indicate that: (a) the 7-day moving average temperature is an efficient variable that can be used to depict water-use variation in a year; (b) a daily maximum temperature of 31.1°C and the occurrence of precipitation are two thresholds of water-use behaviour; and (c) the current day’s water consumption has a strong correlation with the consumption of one, two and seven days ago.

Editor Z.W. Kundzewicz; Associate editor D. Yang

Citation Zhang, D.W., et al., 2013. Statistical interpretation of the daily variation of urban water consumption in Beijing, China. Hydrological Sciences Journal, 59 (1), 181–192.     

Social Mix and the Problematisation of Social Housing

Social housing in Australia is at a significant juncture. High levels of housing stress, increasing levels of socio-spatial polarisation and reduced government funding are posing complex policy challenges. Social mix policies are one response to these challenges, arising from the problematisation of social housing estates as socially excluded. This problematisation is examined through case studies of two Sydney social housing renewal projects: Telopea and Riverwood North. Drawing on interviews with government, private-sector and not-for-profit housing practitioners, the paper identifies two distinct discourses of social exclusion within this problematisation—culture of poverty discourse and equity discourse—that shape the implementation of social mix. These discourses reveal that implementing social mix is more complex than simply managing the cohabitation of residents in different tenures. Rather, the practice of social mix is embedded within discourses about the nature and causes of social exclusion. These discourses, in their turn, inform the multiple and sometimes conflicting aspirations pursued through social mix policies.     

Voronoi图和实景影像在城市POI选址中的应用

以北京西城区为例,通过Voronoi图将兴趣点划分成多个区域;在部件集中且兴趣点少的区域,通过建立基于Voronoi分区的minisum选址模型,得到理论上的新增兴趣点的坐标;然后通过移动道路测量车采集实景影像定位到理论的兴趣点点位上;并在其附近一定范围内寻找最近的有标志意义的地物作为实际位置的兴趣点,达到对兴趣点快速更新的目的,极大提高了城市管理者在日常工作和应对突发事件时的实时性和高效性。     

区域规划空间信息系统建设与应用研究——以江苏省城乡规划信息系统为例

区域性城乡规划信息系统建设开展较晚,与城市级规划信息系统不同,其应用需求、数据构成、技术架构具有其独特性。结合新一轮江苏省城镇体系规划修编工作,开展全省城乡规划信息数据建库和应用平台的开发工作,系统根据区域规划的编制和研究应用需求,制定了面向未来区域规划工作需求的数据标准,集成了全省多源、多尺度、多时态的空间数据,实现了跨专业、跨平台空间信息的整合与共享。为江苏省城镇体系规划以及其他相关编制提供数据分析、规划决策支撑等服务,并预留未来与其他各类地理信息系统的应用接口。     

Monitoring the built-up environment of Shanghai on the street-block level using SAR and volunteered geographic information

ABSTRACT

In this geo-statistical analysis of change detection, we illustrate the evolution of the built-up environment in Shanghai at the street-block level. Based on two TerraSAR-X image stacks with 36 and 15 images, covering the city centre of Shanghai for the time period from 2008 to 2015, a set of coherence images was created using a small baseline approach. The road network from Open Street Map, a volunteered geographic information product, serves as the input dataset to create street-blocks. A street-block is surrounded by roads and resembles a ground parcel, a real estate property – a cadastral unit. The coherence information is aggregated to these street-blocks for each observation and the variation is analysed over time. An analysis of spatial autocorrelation reveals clusters of similar behaviours. The result is a detailed map of Shanghai highlighting areas of change. We argue that the aggregation and grouping of synthetic aperture radar coherence image information to real-world entities (street-blocks) is comprehensible and relevant to the urban planning process. Therefore, this research is a contribution to the community of urban planners, designers, and government agencies who want to monitor the development of the urban landscape.     

Web-based visualization of large 3D urban building models

Adaptive rendering of large urban building models has become an important research issue in three-dimensional (3D) geographic information system (GIS) applications. This study explores a way for rendering web-based 3D urban building models. A client–server hybrid rendering approach is presented for large 3D city models, stored on a remote server through a network. The approach combines an efficient multi-hierarchical building representation with a novel image-based method, 3D image impostor generated on demand by a remote server. This approach allows transferring complex scenes progressively while keeping high visualization quality. We also evaluated the rendering and data transferring performance of the proposed approach.