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911.
Agricultural systems around the world are being severely impacted by changing climate, extreme weather events, urbanisation and neo-liberal (free market) policies. Yet, there are currently few studies on the experiences of those affected by these compounding pressures captured at the local scale. Experiences of adaptive responses – along with recommendations for transformations of the agricultural systems provided by those working in local-level settings – have also not been captured. Yet, such responses provide valuable insights into what can be done, and what needs to be done, to bring about a more equitable and sustainable food system. In this paper, we draw upon the opinions and experiences of those involved in food production and distribution in the historically abundant, peri-urban, region of the Mary Valley, Queensland, Australia. Underpinning the practical and strategic recommendations made by participants is a need for supermarket and government policies to appropriately reflect the immense value of small-scale farmers in sustaining rural communities and enhancing the resilience and sustainability of Australia’s food security. Importantly, our participants in this case study location reiterate that the impacts of climate change are manageable if the farming business is able to generate enough profit to absorb the costs of preparation and recovery from disasters. 相似文献
912.
Impacts of Human Behavioral Heterogeneity on the Benefits of Probabilistic Flood Warnings: An Agent‐Based Modeling Framework 下载免费PDF全文
Erhu Du Samuel Rivera Ximing Cai Laura Myers Andrew Ernest Barbara Minsker 《Journal of the American Water Resources Association》2017,53(2):316-332
Flood forecasts and warnings are intended to reduce flood‐related property damages and loss of human life. Considerable research has improved flood forecasting accuracy (e.g., more accurate prediction of the occurrence of flood events) and lead time. However, the delivery of improved forecast information alone is not necessarily sufficient to reduce flood damage and loss of life, as people have varying responses and reactions to flood warnings. This study develops an agent‐based modeling framework that evaluates the impacts of heterogeneity in human behaviors (i.e., variation in behaviors in response to flood warnings), as well as residential density, on the benefits of flood warnings. The framework is coupled with a traffic model to simulate evacuation processes within a road network under various flood warning scenarios. The results show the marginal benefit associated with providing better flood warnings is significantly constrained if people behave in a more risk‐tolerant manner, especially in high‐density residential areas. The results also show significant impacts of human behavioral heterogeneity on the benefits of flood warnings, and thus stress the importance of considering human behavioral heterogeneity in simulating flood warning‐response systems. Further study is suggested to more accurately model human responses and behavioral heterogeneity, as well as to include more attributes of residential areas to estimate and improve the benefits of flood warnings. 相似文献
913.
AutoRAPID: A Model for Prompt Streamflow Estimation and Flood Inundation Mapping over Regional to Continental Extents 下载免费PDF全文
Michael L. Follum Ahmad A. Tavakoly Jeffrey D. Niemann Alan D. Snow 《Journal of the American Water Resources Association》2017,53(2):280-299
This article couples two existing models to quickly generate flow and flood‐inundation estimates at high resolutions over large spatial extents for use in emergency response situations. Input data are gridded runoff values from a climate model, which are used by the Routing Application for Parallel computatIon of Discharge (RAPID) model to simulate flow rates within a vector river network. Peak flows in each river reach are then supplied to the AutoRoute model, which produces raster flood inundation maps. The coupled tool (AutoRAPID) is tested for the June 2008 floods in the Midwest and the April‐June 2011 floods in the Mississippi Delta. RAPID was implemented from 2005 to 2014 for the entire Mississippi River Basin (1.2 million river reaches) in approximately 45 min. Discretizing a 230,000‐km2 area in the Midwest and a 109,500‐km2 area in the Mississippi Delta into thirty‐nine 1° by 1° tiles, AutoRoute simulated a high‐resolution (~10 m) flood inundation map in 20 min for each tile. The hydrographs simulated by RAPID are found to perform better in reaches without influences from unrepresented dams and without backwater effects. Flood inundation maps using the RAPID peak flows vary in accuracy with F‐statistic values between 38.1 and 90.9%. Better performance is observed in regions with more accurate peak flows from RAPID and moderate to high topographic relief. 相似文献
914.
915.
Nina Vogel 《Journal of Environmental Policy & Planning》2016,18(3):361-378
In contemporary planning discourse and practice, different planning ideas co-exists. How this affects the transition towards a sustainable development is an important question for both research and practice. The aim of this study is to explore potential conflicts between planning goals caught between growth-led planning and sustainability commitments in a case study of Fredericia, Denmark. The paper discusses the underlying, framing and controlling conditions for transition dynamics. The analysis builds largely on the formulated policies, strategies or national goal achievements towards sustainable futures. These are put in the context of planning and political practices, which are interpreted from a sustainability rationale. Here this study introduces hypocrisy as a theoretical-analytical perspective to dispute actual sustainability practices to respond to continuous ambivalent planning measures. The author concludes that disregarding the inherently different internal logics of growths and sustainability leads to planning paradoxes and impedes sustainable transitions pursued. 相似文献
916.
Li Chen Rina Schumer Anna Knust William Forsee 《Journal of the American Water Resources Association》2012,48(1):145-155
Chen, Li, Rina Schumer, Anna Knust, and William Forsee, 2011. Impact of Temporal Resolution of Flow‐Duration Curve on Sediment Load Estimation. Journal of the American Water Resources Association (JAWRA) 48(1): 145‐155. DOI: 10.1111/j.1752‐1688.2011.00602.x Abstract: Estimates of a channel’s annual sediment transport capacity typically incorporate annualized flow‐duration curves. Average daily flow data, commonly used to develop flow‐duration curves, may not adequately describe sediment‐transporting flows in arid and semiarid ephemeral streams. In this study, we examined impacts of varied temporal resolution flow data on annual sediment load estimation. We derived flow‐duration curves for eight sites in the Southwestern United States based on both 15‐min and daily‐averaged flow data. We then estimated sediment loads for both flow‐duration curves using the Sediment Impact Analysis Method, implemented in HEC‐RAS. When average daily flow is used to generate flow‐duration curves, sediment load estimation is lower by up to an order of magnitude. This trend is generally unaffected by uncertainty associated with sediment particle size or hydraulic roughness. The ratio of sediment loads estimated by 15‐min versus daily‐averaged flow‐duration curves is strongly correlated with channel slope, being greater on steep‐slope channels. Sediment loads estimated by the two types of flow‐duration curves are closely correlated, suggesting possible relationships for improving predictions when high‐temporal resolution data are unavailable. Results also suggest that the largest flow contributes significantly to total sediment load, and thus will greatly impact ephemeral stream geomorphology in arid and semiarid regions. 相似文献
917.
Vasić MV Mihailović A Kozmidis-Luburić U Nemes T Ninkov J Zeremski-Škorić T Antić B 《Chemosphere》2012,86(6):585-592
Snow samples were collected near crossroads in Novi Sad, Serbia, during December 2009 to assess metal concentrations (Ca, K, Zn, Fe, Cu, Mn, Al, Pb and Na), fine particle distribution and pH value. The filtered samples of melted snow were analysed, with a focus on particles smaller than a few μm. The most common values of the frequency number distribution curve were either in the range of 0.05-0.07 μm or one order of magnitude higher (0.2-0.5 μm). At examined locations metal concentrations varied from 0.0004 mg L−1 for Pb to 18.9 mg L−1 for Na. Besides Na, which mostly originated from de-icing salt, Ca is found to be the most abundant element in snow indicating the dominant influence of natural factors on snow chemistry. No significant difference was found in concentration of the elements at locations near crossroads with either low or high traffic volume, except for Na and Zn.To investigate how metals were related a correlation analysis was done for the concentrations of metals and with respect to the particle size distribution parameters and pH values. The major influence on the fine particle volume (mass) was concluded to be due to the elements from anthropogenic sources. This conclusion was based on the significant positive correlation between Fe, Zn and Al and the fine particle volume based distribution parameters. 相似文献
918.
城市规划是将持续发展、科学发展作为基础,对于城市发展中的经济结构、环境影响等内容加以规划,以发挥指导规范城市发展的作用。在城市规划的编制过程中要对环境影响加以评价。本文以城市规划与环境评价为出发点,提出规划环境影响评价存在的几点问题及解决思路,在更大的范围内保证城市规划的合理性,为政府相关部门科学决策提供依据。 相似文献
919.
如今城市河道水环境的污染问题越来越严重,已经严重影响了人类的生活以及城市的建设,因此加强城市河道水环境的生态修复已经成为目前急需进行的重要工作之一。本文针对城市河道水环境生态修复的相关问题展开了探讨,首先探讨了关于城市河道水环境生态修复的价值以及在修复过程中应该持守的各方面原则,并根据几种先进的水环境生态修复措施进行了详细的探讨,以期为城市河道水环境修复工作提供参考。 相似文献
920.
本文主要介绍在当前时代背景下,我国城市污水处理回用现状,同时探讨在当前状态下城市污水处理回用的未来发展态势。 相似文献