Global climate change and the politics of disaster

The paper explores the potential political impact of global climate change and, more generally, of natural disaster. Because the affluent West has largely tamed the natural and the social domains, popular clamor for government to anticipate, prevent, and redress disaster increases. I delineate several consequences of the new politics of disaster.     

Innovative policy practices to advance building energy efficiency and retrofitting: Approaches,impacts and challenges in ten C40 cities

This study examines ten programmes to advance energy efficiency and retrofitting of existing, private sector buildings in C40 cities in Asia-Pacific and USA. We set out to identify differing policy approaches, together with potential impacts and implementation challenges for each. Findings unearthed six policy models – both mandatory and voluntary – with unique impacts and challenges. We demonstrate that innovation occurs without new policy inventions and largely by necessity, as new features are added and generic models are adapted to local circumstances. Our sample demonstrated experimentation with benchmarking in the USA, comprehensive regulation in Asia, and voluntary approaches in Australia. Overall, environmental impacts are particularly slow to emerge and plagued with attribution challenges. We found limited evidence of benchmarking programme effectiveness in reducing energy consumption in the short-term, but some indication of mid-term outcomes. Driven by unique local circumstances, the cap-and-trade model stood out by fostering large, sustained and attributable GHG emission reductions and retrofitting. Market and social impacts are highly significant across all programmes, highlighting needs to consider non-environmental impacts in policy evaluation. We emphasise the complementary potential of voluntary and regulatory approaches to advancing energy efficiency and climate resilience. We also underscore the potential for reporting or benchmarking programmes to later transition to models mandating performance improvements, such as cap-and-trade.     

可持续发展环境约束条件下的水资源最优配置及实证研究

在相关理论分析和Weber模型的基础上。拓展建立了面向水资源可持续发展的水资源最优配置模型。引入了基于政府管制的影响作用、沿河流域的水用户的实际消耗水量、实际排放水量、河流中可供使用水量及所排放污水水质水平等5个变量函数．通过政府管制下的水质和水量的河道内流量需求等环境约束条件．确保水资源利用始终满足最小基流水量。通过求量优解，计算得出在环境约束下达到最优配置时各个变量函数与对下游地区外部性之间的相关性。接着。本文对陕北黄土高原沿Y河的35家企业进行了实际调查．收集了2个年度共8个季度的观测值，应用计量经济Pand Data模型。对35个节点、8个季度的共280个数据作为混合样本进行经济计量分析。验证了相关结论。最后。还提出一些制定环境约束条件以及水用户间建立水资源环境生态补偿金机制等政策建议。     

TREE RING RECONSTRUCTIONS OF STREAMFLOW FOR THREE CANADIAN PRAIRIE RIVERS1

ABSTRACT: Information regarding long term hydrological variability is critical for the effective management of surface water resources. In the Canadian Prairie region, growing dependence on major river systems for irrigation and other consumptive uses has resulted in an increasing vulnerability to hydrological drought and growing interprovincial tension. This study presents the first dendrochronological records of streamflow for Canadian Prairie rivers. We present 1,113‐year, 522‐year, and 325‐year reconstructions of total water year (October to September) streamflow for the North Saskatchewan, South Saskatchewan, and Saskatchewan Rivers, respectively. The reconstructions indicate relatively high flows during the 20th Century and provide evidence of past prolonged droughts. Low flows during the 1840s correspond with aridity that extended over much of the western United States. Similarly, an exceptional period of prolonged low flow conditions, approximately 900 A.D. to 1300 A.D., is coincident with evidence of sustained drought across central and western North America. The 16th Century megadrought of the western United States and Mexico, however, does not appear to have had a major impact on the Canadian rivers. The dendrohydrological records illustrate the risks involved if future water policy and infrastructure development in the Canadian Prairies are based solely on records of streamflow variability over the historical record.     

Forest Stand Dynamics and Livestock Grazing in Historical Context

Abstract:  Livestock grazing has been implicated as a cause of the unhealthy condition of ponderosa pine forest stands in the western United States. An evaluation of livestock grazing impacts on natural resources requires an understanding of the context in which grazing occurred. Context should include timing of grazing, duration of grazing, intensity of grazing, and species of grazing animal. Historical context, when and under what circumstances grazing occurred, is also an important consideration. Many of the dense ponderosa pine forests and less-than-desirable forest health conditions of today originated in the early 1900s. Contributing to that condition was a convergence of fire, climate, and grazing factors that were unique to that time. During that time period, substantially fewer low-intensity ground fires (those that thinned dense stands of younger trees) were the result of reduced fine fuels (grazing), a substantial reduction in fires initiated by Native Americans, and effective fire-suppression programs. Especially favorable climate years for tree reproduction occurred during the early 1900s. Exceptionally heavy, unregulated, unmanaged grazing by very large numbers of horses, cattle, and sheep during the late nineteenth and early twentieth centuries occurred in most of the U.S. West and beginning earlier in portions of the Southwest. Today, livestock numbers on public lands are substantially lower than they were during this time and grazing is generally managed. Grazing then and grazing now are not the same.     

Persistence and mobility of 2,4-D in unsaturated soil zone under winter wheat crop in sub-tropical region of India

The present study was undertaken to determine the persistence and mobility of 2,4-dichlorophenoxy acetic acid (2,4-D) in unsaturated soil zone under real field conditions for the wheat crop in Roorkee, India. Three experimental plots were chosen in the agricultural field itself to represent the real field conditions in the study area and the potential movement and persistence of herbicide 2,4-D was investigated under three different irrigation treatments. The presence of herbicide along with soil water content was determined in soil at different depths at a temporal scale. The movement of the herbicide was also simulated numerically by solving the coupled soil water content movement and mass transport equations using HYDRUS-1D. The measured soil water content trends and the 2,4-D concentration profiles showed a good agreement with the numerically simulated results. The maximum effect of the herbicide was primarily retained up to 15 cm of the soil profile. The current existing dosage of 0.5 kg ha⁻¹ of pesticide was found to be safe to avoid soil contamination as no residue of 2,4-D was traced at the end of the wheat crop season in any of the plots. Higher concentrations of 2,4-D were also simulated numerically and the simulated results showed that the safe dosage of pesticide application would depend on irrigation treatments.     

牧民对气候变化的认知及应对措施——以镶黄旗为例

文章通过对镶黄旗60户牧户的调查访问,分析牧户对气候变化和极端气候灾害事件的认知和应对措施,结果显示:牧民对气温有较强的认知能力,而对于降雨和大风的认知与实际相悖;气候变化下牧户对草场情况和水资源状况等生态环境变化的认知来看,牧民对牧草产量、植物种类、土壤沙化、鼠虫害、地下水变化的认知比较明显;牧民对气候变化所采取的措施主要有政策措施、帮助措施和合作方式,而3种措施中牧民主要采取草畜平衡和春节休牧、畜种改良和防疫措施、邻里间的互助来应对气候变化。影响镶黄旗牧民的主要灾害天气主要是旱灾,占灾害天气的75%,从气候灾害事件影响方面的认知来看;气候灾害事件对畜、草、人的影响比较大,且影响程度为畜>草>人;牧民面对气候灾害事件主要采取处理牲畜、购买草料、走场、圈养、外出打工等5种应对措施。     

2015年调水调沙期间黄河悬浮颗粒Pb及其稳定同位素组成变化

通过对2015年黄河调水调沙期间利津水文站悬浮泥沙以及小浪底水库表层沉积物的分析,研究了调水调沙期间黄河入海泥沙中Pb元素的含量及同位素组成的变化特征,探讨了其物质来源及对调水调沙进程的响应.结果表明,调水调沙期间黄河入海泥沙Pb元素含量为18.09~28.35μg/g,平均为21.64μg/g,稳定同位素²⁰⁷Pb/²⁰⁶Pb为0.8367~0.8481,²⁰⁸Pb/²⁰⁶Pb为2.0839~2.0997,与黄土等物质较为接近.Pb含量及稳定同位素组成在调水调沙前、后期均较高,而在调水调沙中间主要时段则较低.利津站悬浮泥沙及小浪底水库沉积物中Pb同位素组成均符合黄河源Pb演化规律,但小浪底水库沉积物Pb元素含量较高,部分站位受到了人类活动的影响.调水调沙进程对该期间黄河入海泥沙Pb的变化及来源有着显著影响,在调水调沙前期和后期,水沙通量小,洪水对下游河床冲刷作用弱,Pb受到中上游沉积物来源影响,导致含量和同位素组成较高.在调水调沙中间的主要时段,利津悬浮泥沙与小浪底水库沉积物显著不同,Pb主要来自洪水对下游河床的冲刷,以自然来源为主,未受到人类活动影响.     

环境规制的蓝色红利效应研究

利用中国工业企业数据库2004~2009年制造业企业数据,以清洁生产目录标准的政策实施为外生冲击事件,基于倍差估计法（DID）实证检验了环境规制对企业盈利能力、盈利质量、波特效应和管理创新成本等蓝色红利的影响.结果发现：环境规制显著提升了制造企业的利润率和企业的现金流充裕性,改善了企业的盈利能力和盈利质量;环境规制显著降低了企业管理创新成本,但波特效应不显著.环境规制的蓝色红利效应存在地方策略互动、企业规模和所有制的异质性：地方政府之间的策略性不合作抑制了环境规制蓝色红利效应.企业规模的扩大提高了管理创新成本,但强化其他相关的蓝色红利效应.环境规制对国有企业的利润率、现金流以及全要素生产率的改善作用强于非国有企业,但更有助于降低非国有企业的管理创新成本.     

空冷塔对大气环境温度湿度影响的数值模拟

运用FLUENT建立空冷塔模型进行数值模拟,研究不同出口温度、环境温度和侧风速度下空冷塔与大气环境之间的传热.结果表明：不同出口温度及环境温度对空冷塔与大气环境间的换热有显著影响.其中,当出口温度升高到328K时,空冷塔近地面层空气温度上升6.22K,而其相对湿度由47.7%降至31.78%,空气干燥程度增大;随着环境温度与排气温度间温差增大,换热效果更为显著,表现为冬季空气干燥程度变化最大,春秋次之,夏季最小.不同环境风速对空冷塔与大气环境间换热区域影响显著,其中,当侧风风速为7m/s时,热交换影响区域可达11.17km,且空冷塔近处相对湿度由47.7%降至39.47%.