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排序方式: 共有365条查询结果,搜索用时 46 毫秒
151.
Lauric Thiault Matthew I. Curnock Georgina G. Gurney Scott F. Heron Nadine A. Marshall Erin Bohensky Nao Nakamura Petina L. Pert Joachim Claudet 《Conservation biology》2021,35(2):598-609
Managing human use of ecosystems in an era of rapid environmental change requires an understanding of diverse stakeholders’ behaviors and perceptions to enable effective prioritization of actions to mitigate multiple threats. Specifically, research examining how threat perceptions are shared or diverge among stakeholder groups and how these can evolve through time is increasingly important. We investigated environmental threat perceptions related to Australia's Great Barrier Reef and explored their associations before and after consecutive years of mass coral bleaching. We used data from surveys of commercial fishers, tourism operators, and coastal residents (n = 5254) conducted in 2013 and 2017. Threats perceived as most serious differed substantially among groups before bleaching but were strongly aligned after bleaching. Climate change became the most frequently reported threat by all stakeholder groups following the coral bleaching events, and perceptions of fishing and poor water quality as threats also ranked high. Within each of the 3 stakeholder groups, fishers, tourism operators, and coastal residents, the prioritization of these 3 threats tended to diverge in 2013, but convergence occurred after bleaching. These results indicate an emergence of areas of agreement both within and across stakeholder groups. Changes in perceptions were likely influenced by high-profile environmental-disturbance events and media representations of threats. Our results provide insights into the plasticity of environmental-threat perceptions and highlight how their convergence in response to major events may create new opportunities for strategic public engagement and increasing support for management. 相似文献
152.
Environmental impact assessment (EIA) is identified as an important instrument for facilitating environmental protection and sustainable development. However, since its emergence there has been a growing interest in examining its translation from theory into practice. This paper reviews the translation of mitigation measures proposed in environmental impact statements (EISs) into planning conditions at two platinum mining and processing projects along the Great Dyke of Zimbabwe. By comparing mitigation measures proposed in EISs and those included in environmental management plans (EMPs), examining views of environmental managers and local residents, as well as field observations the mitigation implementation status is verified and evaluated. Results show that 52% of mitigation measures proposed in EISs and mostly procedural are translated into planning conditions. Residents near the platinum processing plant were not satisfied with the mitigation of sulphur dioxide, dust and noise impacts on their health. The need to incorporate and enforce substantive mitigation measures in EISs and planning conditions is recommended for the future. 相似文献
153.
The Great East Japan Earthquake in March 2011 devastated the eastern region of Japan.Due to the resulting nuclear accident,Japanese Cabinet decided to revise its energy policies.The Energy and Environment Council in National Policy Unit published options on the nation’s scenarios for energy and economy in 2030.We estimated the economic impacts of the options to national economy and households in 2030.Finally,we clarified significant factors to establish a secure,affluent and low-carbon society based on the energy scenarios. 相似文献
154.
正确处理区域发展与生态安全是西部开发战略的关键。以可持续发展为目标的区域空间结构理论 ,分析了在新一轮科技革命和产业革命的新形势下推动区域发展和区域空间结构演变的决定性因素 ,以及实行效益原则与社会公平原则相统一的必要性 ,从中引出西部大开发中确保生态安全的极端重要性。并就实现区域发展与生态安全的双赢目标所必须建立的能力体系和制度体系提出了建议。 相似文献
155.
Abstract: Ecosystem-scale networks of marine protected areas (MPAs) are important conservation tools, but their effectiveness is difficult to quantify in a time frame appropriate to species conservation because of uncertainties in the data available. The dugong ( Dugong dugon ) is a mobile marine species that occurs in shallow inshore waters of an ecosystem-scale network of MPAs (the Great Barrier Reef World Heritage Area [GBRWHA]). We developed a rapid approach to assess risk to dugongs in the region and evaluate options to ameliorate that risk. We used expert opinion and a Delphi technique to identify and rank 5 human factors with the potential to adversely affect dugongs and their sea grass habitats: netting, indigenous hunting, trawling, vessel traffic, and poor-quality terrestrial runoff. We then quantified and compared the distribution of these factors with a spatially explicit model of dugong distribution. We estimated that approximately 96% of habitat of high conservation value for dugongs in the GBRWHA is at low risk from human activities. Using a sensitivity analysis, we found that to decrease risk, commercial netting or indigenous hunting had to be reduced in remote areas and the effects of vessel traffic, terrestrial runoff, and commercial netting had to be reduced in urban areas. This approach enabled us to compare and rank risks so as to identify the most severe risks and locate specific sites that require further management attention. 相似文献
156.
《Environmental Communication: A Journal of Nature and Culture》2013,7(7):958-974
ABSTRACTDrought is defined, experienced, and communicated about in multiple ways. This case study examines individual definitions of drought (timing, impacts, and severity) and attitudes about climate change. Household surveys (n?=?120) were conducted in Cimarron County, Oklahoma and Union County, New Mexico using a stratified random sampling method to select farmers, ranchers, and town residents. Information about drought is primarily communicated between neighbors, friends, and family, as well as media and local governing agencies. Residents perceive the recent drought to be the worst drought on record, regardless of previous drought experiences. Residents reported widespread drought-related impacts on agriculture, environment, and society. Most residents see drought as cyclical and driven by natural causes, rather than human causes. We recommend adaptive drought communication engage more fully with identity, place, and history. Climate information should be presented in a relevant manner to diverse agricultural stakeholders with differing attitudes about climate change, management, and climate information. 相似文献
157.
Background, Aims and Scope This research attempted to identify the dominant factors simultaneously affecting the airborne concentrations of five air
pollutants with principal component analysis and to determine the meteorologically related parameters that cause severe air-pollution
events. According to the definition of subPSI and PSI values through the U.S. EPA, the historical raw data of five criteria
air pollutants, SO2, CO, O3, PM10 and NO2, were calculated as daily subPSI values. In addition to the airborne concentrations,
this study simultaneous collected the surface meteorological parameters of the Taipei meteorological station, established
by the Central Weather Bureau.
Methods Principal component analysis was conducted to screen severe air pollution scenarios for five air pollutants: SO2, CO, O3,
PM10 and NO2. The concentrations of various air pollutants measured at 17 air-quality stations in northern Taiwan from 1995
to 2001 were transformed into daily subPSI values. The correlation analysis of the five air pollutants and four meteorological
parameters (wind speed, temperature, mixing height and ventilation rate) were included in this research. After screening severe
air pollution scenarios, this study recognized the synoptic patterns easily causing the severe air-pollution events.
Results and Discussion Analytical results showed that the eigenvalues of the first two principal components for SO2, CO, O3, PM10 and NO2 were greater
than 1. The first component of five air pollutants explained 64, 64, 67, 76 and 63% of subPSI variance for SO2, CO, O3, PM10
and NO2, respectively. Only the correlation coefficient of NO2 and CO had statistically significant positive values (0.82);
other pollutant pairs presented medium (0.4 to 0.7) or low (0 to 0.4) positive values. The correlation coefficients for air
pollutants and three meteorological parameters (wind speed, mixing height and ventilation index) were medium or low negative
values. In northern Taiwan, spring was most likely induced high concentrations and the component scores of the first component
for SO2, CO, PM10 and NO2; summer was the worst season that caused high O3 episodes. Consequently, the analytical results
of factor loadings for the first principal component and emission inventory of various sources revealed that mobile sources
were dominant factors affecting ambient air quality in northern Taiwan.
Conclusion According to the results of principal component analysis for the five air pollutants, the first two of 17 components were
cited as major factors and explained 71% of subPSI variance. Based on the inventory of NOx emissions and the isopleth diagram
of factor loading for the first component, mobile sources in the southwest Taipei City accounted for the highest factor loading
values and emission inventory values. Synoptic analysis and principal component analysis demonstrated that three types of
weather patterns (high-pressure recirculation, prefrontal warm sector and the southwesterly wind system) easily caused the
severe air-pollution scenarios. In summary, if severe air-pollution days occurred, the average meteorological parameters experienced
adverse conditions for diffusing air pollutants; that is, the average values of wind speed, mixing height and ventilation
index were lower than 2.1 ms-1, 360 m and 800 m2s-1, respectively. If one of the three synoptic patterns were to occur in
combination with adverse meteorological conditions, severe air-pollution events would be developed.
Recommendation and Outlook By utilizing synoptic patterns, this work found three weather systems easily caused severe air-pollution events over northern
Taiwan. Analytical results showed, respectively, the wind speed and mixing height were less than 2.1 m/s and 360 m during
severe air-pollution events. 相似文献
158.
The amount of rainfall in Mazandaran province of Northern Iran is high. Mazandaran has man-made water reservoirs called Ab-bandan, to collect rainfall for irrigating rice farms during the growing seasons. However, rice farms face water scarcity because only a small amount of rainfall is being stored in Ab-bandans, while either the remaining water runs off into the sea, or causes water-logging or flooding. This research addresses Ab-bandans governance gaps in the Mazandaran province, using the ‘Multi-level Governance Framework’ introduced by the Organization for Economic Co-operation and Development (OECD). A modified Delphi technique with face-to-face interviews and a ranking round is used to identify Ab-bandans governance gaps. The identified gaps are classified into seven categories by applying the OECD's framework. In each of the categories there is one most important gap: the lack of a specific law for Ab-bandans, lack of long-term and strategic planning, low recognition of Ab-bandans at the national level, insufficient budget, lack of water user associations, lack of research in practice, and lack of using technology. The findings show that lack of a specific law for Ab-bandans in the country's water law is the most acute gap of all. In addition, the analysis highlights the fact that the policy category is the most critical one. The identified gaps are interlinked and exacerbate each other, therefore, a holistic perspective is needed to understand and resolve them. This study recommends a reform in the country’s water law, improved linkage between levels of government, co-operation among organizations involved in Ab-bandans management, and participation of local stakeholders in planning. 相似文献
159.
Paul E. Todhunter 《Journal of the American Water Resources Association》2001,37(5):1263-1278
ABSTRACT: The flood hydroclimatology of the Grand Forks flood of April 1997, the most costly flood on a per capita basis for a major metropolitan area in United States history, is analyzed in terms of the natural processes that control spring snowmelt flooding in the region. The geomorphological characteristics of the basin are reviewed, and an integrated assessment of the hydroclimatological conditions during the winter of 1996 to 1997 is presented to gain a real‐world understanding of the physical basis of this catastrophic flood event. The Grand Forks flood resulted from the principal flood‐producing factors occurring at either historic or extreme levels, or at levels conducive to severe flooding. Above normal fall precipitation increased the fall soil moisture storage and reduced the spring soil moisture storage potential. A concrete frost layer developed that effectively reduced the soil infiltration capacity to zero. Record snowfall totals and snow cover depths occurred across the basin because of the unusual persistence of a blocking high circulation pattern throughout the winter. A severe, late spring blizzard delayed the snowmelt season and replenished the snow cover to record levels for early April. This blizzard was followed by a sudden transition to an extreme late season thaw due to the abrupt breakdown of the blocking circulation pattern. The presence of river ice contributed to backwater effects and affected the timing of tributary inflows to the main stem of the Red River. Only the absence of spring rains prevented an even more catastrophic flood disaster from taking place. This paper contributes to our understanding of the flood hydroclimatology of catastrophic flood events in an unusual flood hazard region that possesses relatively flat terrain, a north‐flowing river, and an annual peak discharge time series dominated by spring snowmelt floods. 相似文献
160.
Temporal and spatial variation of nitrogen and phosphorus and eutrophication assessment for a typical arid river—Fuyang River in northern China 总被引:1,自引:0,他引:1
Based on water quality surveys over 2 years(July to December,in 2014 and 2015) in a typical arid river in northern China the Xingtai segment of the Fuyang River basin — the variation of nitrogen(N) and phosphorus(P) was analyzed.The extent of water eutrophication of this segment was also assessed using a universal index formula for eutrophic evaluation and a logarithmic power function.The results showed that the average concentration of total N(TN) was 27.2 mg/L(NH_3-N,63.5%),total P(TP) was 2.0 mg/L(solution reactive phosphorus,68.8%).Temporal and spatial variations of N and P in this segment were observed.Concentrations of N and P in the arid season were higher than those in the rainy season.Spatially,the N and P concentrations followed the same trend;i.e.,higher in the city segment than in the suburbs,and decreasing along the river.The water eutrophication in the studied segment reached extremely high levels at all times(eutrophication index ≥76.3).Spatially,its trend was clearly linked with N and P.Water shortage,pollution accumulation and a weak self-purification function are the main reasons for the prominent eutrophication in this segment. 相似文献