Interacting Effects of Landownership, Land Use, and Endangered Species on Conservation of Southwestern U.S. Rangelands

Abstract:  The contemporary southwestern United States is characterized by fire-adapted ecosystems; large numbers of federally listed threatened and endangered species; a patchwork of federal, state, and private landownership; and a long history of livestock grazing as the predominant land use. I compared eight sites in southern Arizona and New Mexico to assess the interacting effects of these characteristics on conservation practices and outcomes. There was widespread interest and private-sector leadership in restoring fire to southwestern rangelands, and there is a shortage of predictive scientific knowledge about the effects of fire and livestock grazing on threatened and endangered species. It was easier to restore fire to lands that were either privately owned or not grazed, in part because of obstacles created by threatened and endangered species on grazed public lands. Collaborative management facilitated conservation practices and outcomes, and periodic removal of livestock may be necessary for conservation, but permanent livestock exclusion may be counterproductive because of interactions with land-use and landownership patterns.     

极限与分配--再论环境法的本位

环境问题是人类活动及其影响超出环境承受能力的极限所造成的后果。解决环境问题最根本的办法是分配，即把有限的环境资源在人类广泛的欲求之间做“相持而长”的分配。这种资源分配不同于收益分配，它体现的基本精神是义务。把体现义务精神的分配方法引入环境立法，必然导致环境法由传统的权利本位转变为义务本位。环境法不得不采用资源分配的办法，以义务为本位，这是由环境这种特殊的物质条件所决定的。     

DISSOLVED GAS ANALYSIS FOR ASSESSING THE FATE OF NITRATE IN WETLANDS1

ABSTRACT: Dissolved gas analysis permits direct detection of ground water denitrification, a technique we used in this study to assess the fate of nitrate in a riparian wetland. Dissolved argon (Ar) and dinitrogen (N₂) were measured in transects of nested piezometers installed at different depths within upwelling regions of a riparian wetland. The method uses the Ar content in the water as a natural inert tracer for assessing background content of N₂ from the previous air/water equilibrium. Within the wetland under study, anoxic to suboxic ground water became more oxic in piezometers close to the aquifer layer, indicating upwelling of oxic ground water. Assessment of loss of nitrate and Ar in ground water within an upwelling zone indicated that shallow piezometers had significant N₂ loss through degassing. Most of the measured nitrate‐nitrogen (NO₃^?‐N) loss of 205 μM in a piezometer nest could be accounted for by total N₂‐N produced (169 μM N), calculated from changes in dissolved N₂ and estimated N₂ degassed. Degassing due to methane (CH₄) production was also detected in some shallow piezometers within nests. This technique for analysis of dissolved gases in ground water can be applied to detect small changes in N gas concentration and aids in assessing the fate of nitrate along a ground water flow path.     

我国淡水中铜的水质基准及生态风险评估研究

铜是生命体必需的微量元素,但是摄入量过高又会对机体产生危害。以我国淡水生态系统为保护对象,选取有代表性的本地物种及敏感性高的模式生物作为受试生物进行急慢性毒理试验,同时,筛选收集其他淡水生物的毒性数据,通过物种敏感度分布法进行铜的水质基准阈值的推导。最后,运用商值法对我国淡水环境中铜的生态风险进行评估。结果表明,铜的短期危险浓度和长期危险浓度分别为30.9,4.1μg/L。铜对我国淡水水体的风险相对较低,在低剂量长期暴露的情况下,部分水体会对水生生物产生潜在的生态风险。     

基于红外吸收法的哈龙替代灭火剂HFC－125的浓度监测技术

HFC-125(五氟乙烷)有较好性能,可替代哈龙灭火剂应用于飞机灭火系统中。在飞机灭火系统的评估实验中,模拟地面或是飞行状态,灭火剂浓度测量设备都是必不可少的。基于非色散红外光谱技术(NDIR),初步设计了HFC-125灭火剂浓度监测设备,该设备采用硅碳红外光源,入射光经过斩波器调制转变为交变光,通过单光路测量气室后,被碲镉汞红外探测器转化为电压信号并被前置放大电路放大。通过电压比与体积分数的对应关系,可以实现对HFC-125浓度的监测。     

Evaluating the Brazilian zero tolerance drinking and driving law: Time series analyses of traffic-related mortality in three major cities

Objective: A zero tolerance alcohol restriction law was adopted in Brazil in 2008. In order to assess the effectiveness of this intervention, the present study compares specific mortality in 2 time series: 1980–2007 and 2008–2013.

Methods: Data on mortality and population were gathered from official Brazilian Ministry of Health information systems. Segmented regression analyses were carried out separately for 3 major Brazilian capitals: Belo Horizonte, Rio de Janeiro, and São Paulo.

Results: In 2 cities (Belo Horizonte and Rio de Janeiro) there were no significant changes in mortality rate trends in 2 periods, 1980 to 2007 and 2008 to 2013, where the observed rates did not differ significantly from predicted rates. In São Paulo, a decreasing trend until 2007 unexpectedly assumed higher levels after implementation of the law.

Conclusion: There is no evidence of reduced traffic-related mortality in the 3 major Brazilian capitals 5.5 years after the zero tolerance drinking and driving law was adopted.     

论《环境保护法》的修改与环境法律制度的完善

建立良好、和谐一致的环境法律体系是我国环境法制建设的重要基础。《环境保护法》确立的环境目标责任制、排污收费制度、环境影响评价制度、限期治理制度和公众参与制度等制度已经不能适应新的市场经济体制和科学发展观的要求,需要变革与创新。许多新的行之有效的管理制度亟待上升为法律制度。因此,《环境保护法》扮演着整合性环境立法的角色,修订时应持资源、环境与生态的整体观念。基于调研和理论思考,提出6点建议：提升立法层次、增强法律权威;确立环境优先、追求社会至善;制约行政权力、明确政府责任;提倡环境自治、保障公众参与;突破诉讼瓶颈、鼓励公益诉讼;理顺权责关系、提高管理效率,以期为《环境保护法》的修改和环境法律制度的完善提供参考。〖     

台湾地区VOCs污染控制法规、政策和标准

台湾地区已经制定了比较完善的挥发性有机物（VOCs）控制法规、政策和标准体系,并在VOCs控制方面取得了很好的效果.本文对台湾地区涉及VOCs控制的政策框架,包括行政管制措施和经济奖惩制度进行了完整的总结和分析,对我国大陆地区VOCs控制政策的制定和实施具有重要的参考价值.     

探求提升环境执法效能的方法——以鄱阳湖生态经济区为例

2009年底,鄱阳湖生态经济区正式成为为国家战略,区域内各地都在不断探索生态与经济协调发展的新路,良好的生态环境对气候调节和生物多样性保护起着重要作用,也对当地经济的可持续发展起到了促进作用。但是由于环境执法过程中的一些问题的存在,如:相关环境立法的不完善,环保部门执法权力有限,企业违规成本低、守法执法成本高,公众环保意识淡薄等,致使鄱阳湖生态经济区内破坏环境的事件频频发生。为提高执法能效,应当完善环境立法,将环保指标纳入地方考核体系,通过立法以提高违规企业的违法成本,建立多部门联合治理机制,加大环境保护的宣传力度。     

冲缝筛管结垢速率模拟研究*

为对防砂过程中因地层物性影响而导致冲缝筛管出现结垢问题进行准确的过程分析,基于FLUENT平台利用现场数据建立流道中的化学反应和沉积结垢的数值模型,评估管道缝宽、环境压力、温度、离子浓度与流速对冲缝筛管结垢速率的影响规律。结果表明:筛管结垢速率与管内温度和离子浓度成正相关,与管内流体流速成负相关,但环境压力影响不大,同时结垢主要产生在冲缝台阶以及冲缝套与打孔基管的接触面上,对产液的过流面积存在较大影响;结合正交分析得到4个敏感因素的主次顺序为:管内温度、管内流速、反应物浓度、环境压力,并确定最小结垢的组合方案;通过DPM模型探究CaCO3颗粒的沉积规律,得到管内的沉积情况,并建立多因素垢层厚度的计算模型。在实际生产中为降低筛管结垢对油井产能的影响,可以通过降低管内的温度、离子浓度及适当地增大流速来抑制结垢过程的发生。