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411.
本文分析总结了环保新常态下面临的环保新形势,对环境管理转型提出的新要求,认为在环境管理模式由污染控制导向向质量改善导向转变,环境管理思路由注重行政许可、事前审批、指标分配向注重事中事后监管、市场自治、社会共治转变的背景下,现有环境管理制度体系整体与政策手段个体的覆盖主体、切入界面、作用机制、内在逻辑等基础理论问题需要再审视,制度架构顶层设计和分工体系需要再完善。在此背景和趋势下,本文从理论和实践两个层面深入探析了名录工具和产品主体在环境管理中的特性与作用,认为产品是市场经济条件下同时承载功能流、价值流和资源环境流的流通载体,也是制定差别化环境监管政策与市场监管政策、建立跨主体环境成本合理分担机制的最恰当主体,以此为基础,清晰界定了环境管理系统化、科学化、法制化、精细化、信息化转型要求下环保综合名录的本质特征、基本定位和潜力方向,并提出了综合名录工作下一阶段的重点任务。 相似文献
412.
长三角地区大气污染治理取得一定成效,然而空气质量改善逐渐进入瓶颈期和攻坚期,大气污染治理战略需要从宏观层面系统谋划。本文系统分析了近10年来长三角区域经济、能源、产业、交通的发展状况和趋势,结合区域大气污染物浓度水平的演变,分析了大气污染与经济社会发展的耦合关系。结合当前区域空气污染的空间分布差异以及经济能源交通结构的内在差别,识别了大气污染的区内差异特征及关键制约因素。在此基础上,从能源结构和产业结构调整、交通结构优化、分区施策、深化治理等角度,为深化区域大气污染联防联控,持续改善大气污染问题提出了政策建议。 相似文献
413.
中三角区域已经是我国第四个国家级城市群,也将成为我国经济增长的"第四极"。在经济发展的同时,更需要以节能减排、资源环境等为重点,以实现经济建设与生态文明"双可持续"的协同发展。本文以二氧化硫、氮氧化物、烟(粉)尘为主要大气污染物,对我国中三角区域大气污染物排放进行了详细的分析,并与京津冀、长三角、珠三角、"三区十群"等进行了多方位比较。结果表明,2013年中三角区域二氧化硫排放量为151.7万t,其中工业二氧化硫排放量为140.1万t;氮氧化物排放量为147.2万t,其中工业氮氧化物排放量为93.6万t;烟(粉)尘排放量为81.8万t,其中工业烟(粉)尘排放量为71.4万t。中三角区域二氧化硫、氮氧化物、烟(粉)尘排放量均位于"四极"的第三。中三角区域二氧化硫、氮氧化物、烟(粉)尘单位GDP排放强度分别为25.03t/亿元、24.29 t/亿元、13.50 t/亿元,分别位于"四极"的第一、第二、第二。同时,本文还从经济发展模式、产业结构调整、煤炭消费方式等方面对我国中三角等经济"四极"提出了相关建议。 相似文献
414.
Vinicius F. Farjalla André M. Amado Albert L. Suhett Frederico Meirelles-Pereira 《Environmental science and pollution research international》2009,16(5):531-538
Background, aim, and scope Dissolved humic substances (HS) usually comprise 50–80% of the dissolved organic carbon (DOC) in aquatic ecosystems. From
a trophic and biogeochemical perspective, HS has been considered to be highly refractory and is supposed to accumulate in
the water. The upsurge of the microbial loop paradigm and the studies on HS photo-degradation into labile DOC gave rise to
the belief that microbial processing of DOC should sustain aquatic food webs in humic waters. However, this has not been extensively
supported by the literature, since most HS and their photo-products are often oxidized by microbes through respiration in
most nutrient-poor humic waters. Here, we review basic concepts, classical studies, and recent data on bacterial and photo-degradation
of DOC, comparing the rates of these processes in highly humic ecosystems and other aquatic ecosystems.
Materials and methods We based our review on classical and recent findings from the fields of biogeochemistry and microbial ecology, highlighting
some odd results from highly humic Brazilian tropical lagoons, which can reach up to 160 mg C L−1.
Results and discussion Highly humic tropical lagoons showed proportionally lower bacterial production rates and higher bacterial respiration rates
(i.e., lower bacterial growth efficiency) than other lakes. Zooplankton showed similar δ13C to microalgae but not to humic DOC in these highly humic lagoons. Thus, the data reviewed here do not support the microbial
loop as an efficient matter transfer pathway in highly humic ecosystems, where it is supposed to play its major role.
In addition, we found that some tropical humic ecosystems presented the highest potential DOC photo-chemical mineralization
(PM) rates reported in the literature, exceeding up to threefold the rates reported for temperate humic ecosystems. We propose
that these atypically high PM rates are the result of a joint effect of the seasonal dynamics of allochthonous humic DOC input
to these ecosystems and the high sunlight incidence throughout the year. The sunlight action on DOC is positive to microbial
consumption in these highly humic lagoons, but little support is given to the enhancement of bacterial growth efficiency,
since the labile photo-chemical products are mostly respired by microbes in the nutrient-poor humic waters.
Conclusions HS may be an important source of energy for aquatic bacteria in humic waters, but it is probably not as important as a substrate
to bacterial growth and to aquatic food webs, since HS consumption is mostly channeled through microbial respiration. This
especially seems to be the case of humic-rich, nutrient-poor ecosystems, where the microbial loop was supposed to play its
major role. Highly humic ecosystems also present the highest PM rates reported in the literature. Finally, light and bacteria
can cooperate in order to enhance total carbon degradation in highly humic aquatic ecosystems but with limited effects on
aquatic food webs.
Recommendations and perspectives More detailed studies using C- and N-stable isotope techniques and modeling approaches are needed to better understand the
actual importance of HS to carbon cycling in highly humic waters. 相似文献
415.
生物法同时脱硫脱硝试验研究 总被引:1,自引:0,他引:1
采用轻质陶粒生物滴滤塔处理摸拟燃煤烟气中二氧化硫和氮氧化物的试验研究,探讨生物法同时脱硫脱硝的影响因素及生物降解宏观动力学。研究结果表明,生物法能有效同时去除烟气中的二氧化硫和氮氧化物,烟气同时脱硫脱硝效率分别可达99.9%和88.9%。为获得最佳烟气同时脱硫脱硝效果,二氧化硫和氮氧化物进气负荷应分别<140 g/(m3·h)和20 g/(m3·h),循环液pH=7~8,空床停留时间为30.28 s,喷淋密度为8.81 L/(m3·h)。 相似文献
416.
M.J. Robertson T.G. Measham G. Batchelor R. George R. Kingwell K. Hosking 《Journal of environmental management》2009,90(10):3023-3030
Community and catchment-based approaches to salinity management continue to attract interest in Australia. In one such approach, Catchment Demonstration Initiative (CDI) projects were established by the Western Australian (WA) Government in 2000 for targeted investment in large-scale catchment-based demonstrations of integrated salinity management practices. The aim was to promote a process for technically-informed salinity management by landholders. This paper offers an evaluation of the effectiveness of one CDI project in the central wheatbelt of WA, covering issues including: its role in fostering adoption of salinity management options, the role of research and the technical requirements for design and implementation of on-ground works, the role of monitoring and evaluation, the identification and measurement of public and private benefits, comparison and identification of the place and value of plant-based and engineering-based options, reliance on social processes and impacts of constraints on capacity, management of governance and administration requirements and an appreciation of the value of group-based approaches.A number of factors may reduce the effectiveness of CDI-type approaches in facilitating landholder action to address salinity, many of these are socially-based. Such approaches can create considerable demands on landholders, can be expensive (because of the planning and accountability required) on the basis of dollars per hectare impacted, and can be difficult to garner ownership from all involved. An additional problem could be that few community groups would have the capacity to run such programs and disseminate the new knowledge so that the CDI-type projects can impact outside the focus catchment. In common with many publicly-funded approaches to salinity, we found that direct benefits on public assets are smaller than planned and that results from science-based requirements of monitoring and evaluation have long lead times, causing farmers to either wait for the information or act sooner and take risks based on initial results. We also found that often it is a clear outline of the process that is of most importance in decision making as opposed to the actual results. We identified limitations in regulatory processes and the capacity for local government to engage in the CDI.The opportunities that CDI-type approaches provide centre around the value of its group-based approach. We conclude that they can overcome knowledge constraints in managing salinity by fostering group-based learning, offer a structured process of trialling options so that the costs and benefits can be clearly and transparently quantified, and avoid the costly mistakes and “learning failures” of the past. 相似文献
417.
This paper considers liberal and nationalist economic policy approaches to the ownership and development of Australian energy resources (oil, gas, coal and uranium). In the two decades prior to 1983, Australia pursued economic policies in relation to its energy resources which could broadly be described as ‘nationalist’. Governments of the day intervened in development decisions in an effort to enhance the ‘national interest’. From 1983, along with the deregulation of the Australian economy as a whole, policy relating to energy resources was liberalised. Development of energy reserves henceforth occurred according to the dictates of the market. This paper argues that recent Australian energy policy initiatives reflect an increase in nationalist influences and a retreat from the liberalisation agenda that dominated energy policy making in the 1980s and 1990s. Three examples are discussed where policy has been influenced by a nationalist framework: (1) the domestic gas reservation policy in Western Australia; (2) Australian government efforts to promote a ‘value adding’ nuclear processing industry and (3) Australian Labor Party policy giving preferential financial incentives for gas to liquids projects. The re-emergence of nationalism in Australia is occurring either because policy makers now favour it as a path to energy security or in some cases because they believe that appeals to nationalism will generate political support. 相似文献
418.
Frank Merry Britaldo Soares-Filho Daniel Nepstad Gregory Amacher Hermann Rodrigues 《Environmental management》2009,44(3):395-407
Logging has been a much maligned feature of frontier development in the Amazon. Most discussions ignore the fact that logging
can be part of a renewable, environmentally benign, and broadly equitable economic activity in these remote places. We estimate
there to be some 4.5 ± 1.35 billion m3 of commercial timber volume in the Brazilian Amazon today, of which 1.2 billion m3 is currently profitable to harvest, with a total potential stumpage value of $15.4 billion. A successful forest sector in
the Brazilian Amazon will integrate timber harvesting on private lands and on unprotected and unsettled government lands with
timber concessions on public lands. If a legal, productive, timber industry can be established outside of protected areas,
it will deliver environmental benefits in synergy with those provided by the region’s network of protected areas, the latter
of which we estimate to have an opportunity cost from lost timber revenues of $2.3 billion over 30 years. Indeed, on all land
accessible to harvesting, the timber industry could produce an average of more than 16 million m3 per year over a 30-year harvest cycle—entirely outside of current protected areas—providing $4.8 billion in returns to landowners
and generating $1.8 billion in sawnwood sales tax revenue. This level of harvest could be profitably complemented with an
additional 10% from logging concessions on National Forests. This advance, however, should be realized only through widespread
adoption of reduced impact logging techniques. 相似文献
419.
Kerry A. Brown J. Carter Ingram Dan F. B. Flynn Rova Razafindrazaka Vololoniaina Jeannoda 《Environmental management》2009,44(1):136-148
Despite their prevalence in both developed and developing countries, there have been surprisingly few field assessments of
the ecological effectiveness of protected areas. This study aimed to assess the effectiveness of a key protected area in eastern
Madagascar, Ranomafana National Park (RNP). We established paired 100 × 4-m vegetation transects (400 m2) within RNP and in remnant forests in the park’s peripheral zone. In each 400-m2 plot, all woody stems >1.5 cm in diameter at breast height were measured and identified to species. All species were also
identified as native or non-native. We identified utilitarian species within all transects and they were sorted into use category.
We calculated plot-level taxonomic biodiversity and functional diversity of utilitarian species; the latter was calculated
by clustering the multivariate distances between species based on their utilitarian traits, and all metrics were tested using
paired t-tests. Our results showed that there was significantly higher biodiversity inside RNP than in remnant forests and this pattern
was consistent across all diversity metrics examined. Forests not located within the park’s boundary had significantly higher
non-native species than within RNP. There was no statistically significant difference in functional diversity of utilitarian
species inside RNP vs. remnant forests; however, the overall trend was toward higher diversity inside park boundaries. These
findings suggested that RNP has been effective at maintaining taxonomic diversity relative to surrounding unprotected areas
and restricting the spread of non-native plants. The results also suggested that low functional redundancy of forests outside
of RNP might be of concern, because residents in surrounding villages may have few other substitutes for the services provided
by species that are of critical importance to their livelihoods. This study highlights the challenges of trying to reconcile
biodiversity conservation with human use of natural resources in economically poor, remote areas. 相似文献
420.
This paper evaluates risk factors that influence the probability that a house will burn from wildfire. A logistic regression is used to analyse data processed from pre-fire and post-fire IKONOS images and other geo-referenced data. The dependent variable is the probability that a given house will burn. A total of 12 independent variables are evaluated: vegetation density; area of defensible space; adjacency of a parcel to public lands; proximity of a house to fire station; road width; road type; parcel size; subdivision morphology; assessed value; elevation; slope and aspect. Model results generally support dominant land use planning and design strategies for wildfire risk reduction including vegetation treatments, site selection with respect to topography, and improving access to fire stations. 相似文献