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551.
渤海环流对近岸海域无机氮分布特征的影响   总被引:2,自引:0,他引:2  
基于2017年渤海近岸海域无机氮监测数据和HYCOM数值模拟结果,分析了渤海环流对无机氮污染分布特征的影响,结果表明渤海无机氮的空间分布特征与其环流结构密切相关:受渤海环流的影响,在春、夏、秋季,无机氮含量高值区呈现不同的强度和范围;在辽东湾,与春季相比,夏季环流结构与春季相反、速度大于春季,盘锦、营口近岸海域夏季无机氮污染范围缩小、含量降低,在锦州近岸海域亦出现高值;在渤海湾、莱州湾,与春季相比,夏季和秋季无机氮含量高值区范围缩小,无机氮含量等值线均随环流向高值中心扩展。  相似文献   
552.
This expert opinion study examined the current status of the intertidal zone in the Western Indian Ocean (WIO) and ranked and discussed future management approaches. Information was gathered from scientists, practitioners, and managers active in the WIO region through a questionnaire and a workshop. The experts stated that the productive intertidal environment is highly valuable for reasons such as recreation, erosion protection, and provision of edible invertebrates and fish. Several anthropogenic pressures were identified, including pollution, harbor activities, overexploitation, and climate change. The experts considered the WIO intertidal zone as generally understudied, undermanaged, and with poor or no monitoring. The most important management strategies according to the expert opinions are to develop and involve local people in integrated coastal zone management (ICZM), to increase knowledge on species–environment relationships, and to develop awareness campaigns and education programs. To improve coastal environmental management and conservation, we argue that the intertidal zone should be treated as one organizational management unit within the larger framework of ICZM.

Electronic supplementary material

The online version of this article (doi:10.1007/s13280-013-0465-8) contains supplementary material, which is available to authorized users.  相似文献   
553.
The objective of this article is to speculate on resort restructuring in the market-oriented reform process in China.Previous studies show that spatial disequilibrium was aggravated by decentralization,which leads to the difference in tourism policy and investment,public goods,and service;a profound analytical framework is much needed for further empirical studies.This article has reviewed the relevant studies on links between decentralization and restructuring,spatial influences of decentralization on tourism,based on which we put forward the theoretical framework of resort spatial restructuring from the view of political economy analysis,then we elaborate on and discuss it based on the example of Sanya,China.In short,the article suggests that decentralization of fiscal responsibilities and institutional power contributes to the spatial disequilibrium of tourism industrial structure,land use,public infrastructure and service facilities,and to community inequality.Interests of government,investors,and community should be comprehensively coordinated in the resort spatial restructuring process from three aspects:restructuring government,optimizing space structure,and tourism industry.Furthermore,we argue that resort restructuring in the context of Sanya requires coordination of various interest groups through four ways:restructure the government power under administrative division adjustment,optimizing spatial structure,expanding industrial space to diversified tourism products,and building resort management services organization.Finally,we discussed some policy requirements for resort sustainable development.  相似文献   
554.
We present the results of a study using a document-based evaluation method to better understand how residents in vulnerable coastal areas respond to risk communications about sea-level rise (SLR) and to determine whether communications localized for specific populations improve reception. Similar to climate change communication, SLR risk communication presents challenges involving complex science, uncertainty, invisibility, and politicization. To be comprehensible and persuasive, risk messages must be appropriately framed and visually compelling and must take into account risk perceptions and diverse viewpoints. Our approach involves assessing people's encounters with actual risk messages to determine their reactions and responses. Participants in this study had difficulty understanding information and expressed attitudes including fear, fatalism, skepticism, and loss. SLR risks were also perceived as both temporally and spatially distant, creating a challenge for communicators trying to convey a sense of urgency. We conclude by considering the implications of audience-focused research for SLR risk communication.  相似文献   
555.
Climate change is a significant global risk that is predicted to be particularly devastating to coastal communities. Climate change adaptation and mitigation have been hindered by many factors, including psychological barriers, ineffective outreach and communication, and knowledge gaps. This qualitative study compares an expert model of climate change risks to county administrators' “mental” models of climate change and related coastal environmental hazards in Crystal River, Florida, USA. There were 24 common nodes in the expert and the combined non-expert models, mainly related to hurricanes, property damage, and economic concerns. Seven nodes mentioned by non-experts fit within, but were not a part of, the expert model, primarily related to ecological concerns about water quality. The findings suggest that effective climate outreach and communication could focus on compatible parts of the models and incorporate local concerns to find less controversial ways to discuss climate-related hazards.  相似文献   
556.
土地利用变化下沿海地区吸附态磷负荷动态变化研究   总被引:2,自引:0,他引:2  
吸附态磷是主要的面源污染物之一,它会导致水域环境质量恶化,是水体富营养化的重要污染源。科学估算吸附态磷污染负荷能够为治理沿海地区非点源污染,保护海洋生态安全提供理论依据。以遥感影像、降雨监测资料等多源数据为基础,综合考虑土壤侵蚀、泥沙输移率、磷富集系数等影响因子,构建吸附态磷负荷估算模型,估算了江苏沿海地区2000~2010年吸附态磷负荷量,分析了不同土地利用背景下吸附态磷负荷的动态变化特征,结果显示:(1)2000~2010年,江苏沿海地区吸附态磷负荷明显增加,平均吸附态磷负荷模数由105.89 kg/km2·a增长至201.67 kg/km2·a,吸附态磷负荷总量由3 284t增长至6 255t。(2)10 a间,研究区的吸附态磷负荷热点面积减小,呈现出收敛聚集的态势,但热点区的吸附态磷负荷总量却明显增加,说明研究区内吸附态磷负荷的空间极化现象更为显著。(3)10 a间,各土地利用类型的平均吸附态磷负荷模数都显著增长,不同土地利用背景下吸附态磷负荷总量排序为水田旱地林地草地未利用地园地。研究结果表明,不同土地利用背景下吸附态磷负荷存在显著差异,且不同土地利用类型相互转化时,吸附态磷负荷也随之发生变化,可通过调整土地利用结构,优化景观格局,减少和控制磷污染的发生。  相似文献   
557.
Coastal ecosystems are dependent on terrestrial freshwater export which is affected by both climate trends and natural climate variability. However, the relative role of these factors is not clear. Here, both climate trends and internal climate variabilities at different time scales are related to variations in terrestrial freshwater export into the eastern United States (U.S.) coastal region. For the recent 35‐year period, the intensified hydro‐meteorological processes (annual precipitation or evapotranspiration) may explain the observed streamflow variability in the northeast. However, in the southeast, streamflow is positively correlated with climate variability induced by the Pacific Ocean conditions (El Nino‐Southern Oscillation [ENSO] and Pacific Decadal Oscillation) rather than Atlantic Ocean conditions (Atlantic Multi‐decadal Oscillation and North Atlantic Oscillation). The centroid location for volume of terrestrial freshwater export integrated along the eastern U.S. has a positive temporal trend and is negatively correlated with ENSO conditions, suggesting the northward trend in freshwater export to U.S. eastern coast may be disturbed by the natural climate variability, especially ENSO conditions, i.e., the center of freshwater mass moves southward (northward) during El Nino (La Nina) years. The results indicate the spatial and temporal variations in freshwater export from the eastern U.S. are affected by both climate change and inter‐annual climate variability during the recent 35‐year period (1980‐2014).  相似文献   
558.
Interactive sea-level rise viewers (ISLRVs) are digital tools used to communicate about impacts of sea-level rise (SLR) and support decision-making. This study characterizes how ISLRVs communicate about SLR-related risks and provide decision-making support. It identifies key themes about fostering accurate mental models of SLR processes, informing about inundation likelihood, communicating about related social and ecological risks, and providing features users can apply to specific tasks. We present a framework for understanding this type of communication tool that designers can use to develop robust ISLRVs that can support audiences’ understanding and decision-making needs, and contribute to enhancement of coastal resiliency.  相似文献   
559.
Local and scientific knowledge, when adequately and properly integrated, produces enormous benefits for natural resource management in comparison to a single knowledge system being used. Adequate and proper integration has major constraints that include ineffective use of the integrated knowledge, thoroughly inclusive processes, and true public participation. A six-stage framework is developed using the results and conclusions of two case studies regarding sustainable management of eroding mangrove-dominated muddy coasts in Vam Ray, Hon Dat district, Kien Giang Province, Vietnam. The framework does not stop with the creation of integrated knowledge, but should undergo a longer process. The new knowledge developed in this framework is the understanding gained and lessons learnt during the testing of products of multiple knowledge systems in a local context rather than products of integrated knowledge systems themselves. The Vam Ray framework promotes a high level of participation, effective use of products of multiple knowledge systems, maximum integration of local and scientific knowledge, local ownership, and sustainability. Therefore, the Vam Ray framework adds a new dimension to the literature in relation to integration of local and scientific knowledge in natural resource management.  相似文献   
560.
Fog and low cloud cover (FLCC) and late summer recharge increase stream baseflow and decrease stream temperature during arid Mediterranean climate summers, which benefits salmon especially under climate warming conditions. The potential to discharge cool water to streams during the late summer (hydrologic capacity; HC) furnished by FLCC and recharge were mapped for the 299 subwatersheds ranked Core, Phase 1, or Phase 2 under the National Marine Fisheries Service Recovery Plan that prioritized restoration and threat abatement action for endangered Central California Coast Coho Salmon evolutionarily significant unit. Two spatially continuous gridded datasets were merged to compare HC: average hrs/day FLCC, a new dataset derived from a decade of hourly National Weather Satellite data, and annual average mm recharge from the USGS Basin Characterization Model. Two use‐case scenarios provide examples of incorporating FLCC‐driven HC indices into long‐term recovery planning. The first, a thermal analysis under future climate, projected 65% of the watershed area for 8–19 coho population units as thermally inhospitable under two global climate models and identified several units with high resilience (high HC under the range of projected warming conditions). The second use case investigated HC by subwatershed rank and coho population, and identified three population units with high HC in areas ranked Phase 1 and 2 and low HC in Core. Recovery planning for cold‐water fish species would benefit by including FLCC in vulnerability analyses.  相似文献   
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