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51.
A modified two-dimensional Eulerian air quality model was used to simulate both the gaseous and particulate pollutant concentrations during October 21-24, 2004 in the Pearl River Delta (PRD) region, China. The most significant improvement to the model is the added capability to predict the secondary organic aerosols (SOA) concentrations because of the inclusion of the SOA formation chemistry. The meteorological input data were prepared using the CALMET meteorological model. The concentrations of aerosol-bound species such as NO3^-, NH4^+, SO4^2-, and SOA were calculated in the fine particle size range (〈2.5 μm). The results of the two-dimensional model were compared to the measurements at the ground level during the PRD Intensive Monitoring Campaign (IMC). Overall, there were good agreements between the measured and modeled concentrations of inorganic aerosol components and O3. Both the measured and the modeled results indicated that the maximum hourly O3 concentrations exceeded the China National Air Quality Standard. The predicted 24-h average SOA concentrations were in reasonable agreement with those predicted by the method of minimum OC/EC ratio. 相似文献
52.
本文构建了包括监管的立法、组织体系、监管权力配置、监管工具与程序、问责机制、监管能力等要素在内的环境监管体制分析框架,从污染物排放趋势、国家制度建设等角度分析了"十三五"时期中国环境监管体制改革面临的挑战、目标和思路。"十三五"时期是中国生态文明建设的重要时期,完善环境监管制度是推进生态文明制度体系建设的重要内容。面对严重环境污染所带来的挑战,在此期间加快环境监管体制改革、提高环境监管有效性是切实实现治污减排的根本保证。完善环境监管体系、改进监管方式、创新监管手段是建立治污减排长效机制的基础和前提,也是完善环境治理体系的重要内容。按照市场经济条件下政府依法行政的要求,中国环境监管体制改革的目标,就是要按照合法性、独立性、透明性、可问责性、专业性和执法能力、可信性等原则建立和完善现代环境监管体制,为此必须从专门立法、组织结构、权力分配、问责机制、监管程序与工具、监管能力建设等各方面推进改革。本文提出了"十三五"时期环境监管体制改革的思路及若干建议,主要包括:加快修订环保法律法规,提高法律的可操作性,推进环境司法常态化、规范化和专门化,进一步提升环境监管法治化水平;从纵向、横向上优化环境监管组织结构,强化区域层级的监管与督查功能,强化中央层级环境监管机构对环境信息的获取能力;优化环境保护主管部门机构设置以及相关职能,建立并完善内部机构的协调机制;完善环境监管的内外部问责机制,把做实对监管者的监管机制作为优化环境监管体制的抓手;强化对监管工具的顶层设计,做实监管程序中关键环节,建立环境监管影响评估制度;加强环境监管能力建设,推进环境监管制度队伍职业化发展,保障各级环境监管机构具有充分履职的能力。环境监管体制的改革和完善,是国家治理体系和治理能力现代化的重要内容。 相似文献
53.
Temporal Trends in the Spatial Distribution of Impervious Cover Relative to Stream Location
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J. Wickham A. Neale M. Mehaffey T. Jarnagin D. Norton 《Journal of the American Water Resources Association》2016,52(2):409-419
Use of impervious cover is transitioning from an indicator of surface water condition to one that also guides and informs watershed planning and management, including Clean Water Act (33 U.S.C. §1251 et seq.) reporting. Whether it is for understanding surface water condition or planning and management, impervious cover is most commonly expressed as summary measurement (e.g., percentage watershed in impervious cover). We use the National Land Cover Database to estimate impervious cover in the vicinity of surface waters for three time periods (2001, 2006, 2011). We also compare impervious cover in the vicinity of surface waters to watershed summary estimates of impervious cover for classifying the spatial pattern of impervious cover. Between 2001 and 2011, surface water shorelines (streams and water bodies) in the vicinity of impervious cover increased nearly 10,000 km. Across all time periods, approximately 27% of the watersheds in the continental United States had proximally distributed impervious cover, i.e., the percentage of impervious cover in the vicinity of surface waters was higher than its watershed summary expression. We discuss how impervious cover spatial pattern can be used to inform watershed planning and management, including reporting under the Clean Water Act. 相似文献
54.
This paper focuses on comparative review and analysis of the systems of environmental protection, national environmental strategies
and fundamentals of environmental legislation in Australia and the Russian Federation. These countries have many socioeconomic
similarities, such as low population densities and richness in natural resources which are largely exported. The main disparity
between Australia and Russia is in the types of economy. This paper ‘continues’ the sequence of recent scholarly publications
on comparison of various features of environmental policies in the countries from all over the world. Comparative analysis
in this research has been based on examination of scholarly publications, legislation, government documents, mass media sources
and NGO responses. The analysis has revealed a number of differences including top-down implementation of policies in Russia
whereas in Australia, each State (Territory) implements policies with significant independence from the Commonwealth Government.
At the same time, similarities between the countries have been identified: for example, in deficits in the budget of local
environmental authorities and in the presence of contradictions in legislation at national and regional levels of government.
Suggestions resulting from this analysis include further integration of sustainable development strategies at all levels of
Australian government to encourage further protection of the environment and, for Russia, creating a separate Ministry of
Environmental Protection. These approaches should assist facilitation of sustainable development for both nations.
Readers should send their comments on this paper to: BhaskarNath@aol.com within 3 months of publication of this issue. 相似文献
55.
Himayatullah Khan 《Environment, Development and Sustainability》2009,11(2):293-305
Using survey-based data approach for modeling the demand for environmental goods/resources, this study estimates income and
price elasticities of demand for improved environmental quality of two National Parks in Northern Pakistan. The study uses
data from two studies. The estimates indicate that improved environmental quality effects can be described as a luxury and
an ordinary and price elastic service. Confidence intervals show however that the classification as a luxury is not statistically
significant. Income elasticities of willingness to pay are estimated for a broad range of environmental services. The study
finds that income and willingness to pay vary directly and significantly. The elasticity estimates, in general, are greater
than zero, but less than unity. The study concludes that environmental improvements are more beneficial to low-income groups
than for high-income groups.
相似文献
Himayatullah KhanEmail: |
56.
A highly resolved temporal and spatial air pollutant emission inventory for the Pearl River Delta region, China and its uncertainty assessment 总被引:31,自引:0,他引:31
Junyu Zheng Lijun Zhang Wenwei Che Zhuoyun Zheng Shasha Yin 《Atmospheric environment (Oxford, England : 1994)》2009,43(32):5112-5122
A highly resolved temporal and spatial Pearl River Delta (PRD) regional emission inventory for the year 2006 was developed with the use of best available domestic emission factors and activity data. The inventory covers major emission sources in the region and a bottom–up approach was adopted to compile the inventory for those sources where possible. The results show that the estimates for SO2, NOx, CO, PM10, PM2.5 and VOC emissions in the PRD region for the year 2006 are 711.4 kt, 891.9 kt, 3840.6 kt, 418.4 kt, 204.6 kt, and 1180.1 kt, respectively. About 91.4% of SO2 emissions were from power plant and industrial sources, and 87.2% of NOx emissions were from power plant and mobile sources. The industrial, mobile and power plant sources are major contributors to PM10 and PM2.5 emissions, accounting for 97.7% of the total PM10 and 97.2% of PM2.5 emissions, respectively. Mobile, biogenic and VOC product-related sources are responsible for 90.5% of the total VOC emissions. The emissions are spatially allocated onto grid cells with a resolution of 3 km × 3 km, showing that anthropogenic air pollutant emissions are mainly distributed over PRD central-southern city cluster areas. The preliminary temporal profiles were established for the power plant, industrial and on-road mobile sources. There is relatively low uncertainty in SO2 emission estimates with a range of −16% to +21% from power plant sources, medium to high uncertainty for the NOx emissions, and high uncertainties in the VOC, PM2.5, PM10 and CO emissions. 相似文献
57.
Warmer, drier summers brought by climate change increase the potential risk of wildfires on the moorland of the Peak District of northern England. Fires are costly to fight, damage the ecosystem, harm water catchments, cause erosion scars and disrupt transport. Fires release carbon dioxide to the atmosphere. Accurate forecasts of the timing of fires help deployment of fire fighting resources. 相似文献
58.
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
59.
Use of Descriptors of Ecosystem Functioning for Monitoring a National Park Network: A Remote Sensing Approach 总被引:1,自引:0,他引:1
Baseline assessments and monitoring of protected areas are essential for making management decisions, evaluating the effectiveness
of management practices, and tracking the effects of global changes. For these purposes, the analysis of functional attributes
of ecosystems (i.e., different aspects of the exchange of matter and energy) has advantages over the traditional use of structural
attributes, like a quicker response to disturbances and the fact that they are easily monitored through remote sensing. In
this study, we described the spatiotemporal patterns of different aspects of the ecosystem functioning of the Spanish national
parks and their response to environmental changes between 1982 and 2006. To do so, we used the NOAA/AVHRR-GIMMS dataset of
the Normalized Difference Vegetation Index (NDVI), a linear estimator of the fraction of photosynthetic active radiation intercepted
by vegetation, which is the main control of carbon gains. Nearly all parks have significantly changed during the last 25 years:
The radiation interception has increased, the contrast between the growing and nongrowing seasons has diminished, and the
dates of maximum and minimum interception have advanced. Some parks concentrated more changes than others and the degree of
change varied depending on their different environmental conditions, management, and conservation histories. Our approach
identified reference conditions and temporal changes for different aspects of ecosystem functioning, which can be used for
management purposes of protected areas in response to global changes. 相似文献
60.
Long-range atmospheric transport of three toxaphene congeners across Europe. Modeling by chained single-box FATEMOD program 总被引:1,自引:1,他引:0
Jaakko Paasivirta Seija Sinkkonen Vladimir Nikiforov Fedor Kryuchkov Erkki Kolehmainen Katri Laihia Arto Valkonen Manu Lahtinen 《Environmental science and pollution research international》2009,16(2):191-205
Background, aims, and scope Since toxaphene (polychlorocamphene, polychloropinene, or strobane) mixtures were applied for massive insecticide use in the
1960s to replace the use of DDT, some of their congeners have been found at high latitudes far away from the usage areas.
Especially polychlorinated bornanes have demonstrated dominating congeners transported by air up to the Arctic areas. Environmental
fate modeling has been applied to monitor this phenomenon using parallel zones of atmosphere around the globe as interconnected
environments. These zones, shown in many meteorological maps, however, may not be the best way to configure atmospheric transport
in air trajectories. The latter could also be covered by connecting a chain of simple model boxes. We aim to study this alternative
approach by modeling the trajectory chain using catchment boxes of our FATEMOD model. Polychlorobornanes analyzed in biota
of the Barents Sea offered one case to study this modeling alternative, while toxaphene has been and partly still is used
massively at southern East Europe and around rivers flowing to the Aral Sea.
Materials and methods Pure model substances of three polychlorobornanes (toxaphene congeners P26, P50, and P62) were synthesized, their environmentally
important thermal properties measured by differential scanning calorimetry, as evaluated from literature data, and their temperature
dependences estimated by the QSPR programs VPLEST, WATSOLU, and TDLKOW. The evaluated property parameters were used to model
their atmospheric long-range transport from toxaphene heavy usage areas in Ukraine and Aral/SyrDarja/AmuDarja region areas,
through East Europe and Northern Norway (Finnmarken) to the Barents Sea. The time period used for the emission model was June
1997. Usual weather conditions in June were applied in the model, which was constructed by chaining FATEMOD model boxes of
the catchment’s areas along assumed maximal air flow trajectories. Analysis of the three chlorobornanes in toxaphene mixtures
function as a basis for the estimates of emission levels caused by its usage. High estimate (A) was taken from contents in
a Western product chlorocamphene and low estimate (B) from mean contents in Russian polychloroterpene products to achieve
modeled water concentrations. Bioaccumulation to analyzed lipid of aquatic biota at the target region was estimated by using
statistical calculation for persistent organic pollutants in literature.
Results The results from model runs A and B (high and low emission estimate) for levels in sea biota were compared to analysis results
of samples taken in August 1997 at Barents Sea. The model results (ng g−1 lw): 4–95 in lipid of planktovores and 7–150 in lipid of piscivores, were in fair agreement with the analysis results from
August 1997: 21–31 in Themisto libellula (chatka), 26–42 in Boreocadus saida (Polar cod), and 5–27 in Gadus morhua (cod) liver.
Discussion The modeling results indicate that the application of chained simple multimedia catchment boxes on predicted trajectory is
a useful method for estimation of volatile airborne persistent chemical exposures to biota in remote areas. For hazard assessment
of these pollutants, their properties, especially temperature dependences, must be estimated by a reasonable accuracy. That
can be achieved by using measurements in laboratory with pure model compounds and estimation of properties by thermodynamic
QSPR methods. The property parameters can be validated by comparing their values at an environmental temperature range with
measured or QSPR-estimated values derived by independent methods. The chained box method used for long-range air transport
modeling can be more suitable than global parallel zones modeling used earlier, provided that the main airflow trajectories
and properties of transported pollutants are predictable enough.
Conclusions Long-range air transport modeling of persistent, especially photo-resistant organic compounds using a chain of joint simple
boxes of catchment’s environments is a feasible method to predict concentrations of pollutants at the target area. This is
justified from model results compared with analytical measurements in Barents Sea biota in August 1997: three of six modeled
values were high and the other three low compared to the analysis results. The order of magnitude level was similar in both
modeled (planktovore and piscivore) and observed (chatka and polar cod) values of lipid samples. The obtained results were
too limited to firm validation but are sufficient to justify feasibility of the method, which prompts one to perform more
studies on this modeling system.
Recommendations and perspectives For assessment of the risk of environmental damages, chemical fate determination is an essential tool for chemical control,
e.g., for EU following the REACH rules. The present conclusion of applicability of the chained single-box multimedia modeling
can be validated by further studies using analyses of emissions and target biota in various other cases. To achieve useful
results, fate models built with databases having automatic steps for most calculations and outputs accessible to all chemical
control professionals are essential. Our FATEMOD program catchments at environments and compound properties listed in the
database represent a feasible tool for local, regional, and, according our present test results, for global exposure predictions.
As an extended use of model, emission estimates can be achieved by reversed modeling from analysis results of samples corresponding
to the target area.
This article is dedicated to the memory of Professor Alexander B Terentiev (who passed away in November 2006), our true friend.
With his Institute of Organo-Element Compounds, Russian Academy of Science, Moscow, he was an important main organizer of
the six joint Finnish–Russian seminars (every third year since 1989) on the field (‘Chemistry and Ecology of Organo-Element
Compounds’). He prompted us especially to search properties and environmental fates for various polyhalogen compounds. We
remember him for his friendly character and great sense of humor. 相似文献