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701.
Although theorists have suggested that aquatic environments or “blue space” might have particular restorative potential, to date there is little systematic empirical research on this issue. Indeed the presence of water has, unintentionally, been a confounding factor in research comparing people’s reactions to built and natural environments. Whereas aquatic features (rivers, lakes, coasts) are frequently present in visual stimuli representing natural environments they are rarely incorporated in stimuli portraying built environments. As many towns are, for good reason, located near water this is a potentially significant oversight. The current research collated a set of 120 photographs of natural and built scenes, half of which contained “aquatic” elements. Proportions of “aquatic”/“green”/“built” environments in each scene (e.g. 1/3rd, 2/3rds) were also standardised. Two studies investigated preferences (attractiveness, willingness to visit and willingness to pay for a hotel room with the view), affect and perceived restorativeness ratings for these photographs. As predicted, both natural and built scenes containing water were associated with higher preferences, greater positive affect and higher perceived restorativeness than those without water. Effect sizes were consistently large. Intriguingly, images of “built” environments containing water were generally rated just as positively as natural “green” space. We propose a number of avenues for further research including exploration of the mechanisms underlying these effects.  相似文献   
702.
Antibiotic resistance genes(ARGs), human pathogenic bacteria(HPB), and HPB carrying ARGs are public issues that pose a high risk to aquatic environments and public health. Their diversity and abundance in water, intestine, and sediments of shrimp culture pond were investigated using metagenomic approach. A total of 19 classes of ARGs, 52 HPB species, and 7 species of HPB carrying ARGs were found. Additionally, 157, 104, and 86 subtypes of ARGs were detected in shrimp intestine, pond water, and sediment samples, respectively. In all the samples, multidrug resistance genes were the highest abundant class of ARGs. The dominant HPB was Enterococcus faecalis in shrimp intestine, Vibrio parahaemolyticus in sediments, and Mycobacterium yongonense in water, respectively. Moreover, E. faecalis(contig Intestine_364647)and Enterococcus faecium(contig Intestine_80272) carrying efr A, efr B and ANT(6)-Ia were found in shrimp intestine, Desulfosaricina cetonica(contig Sediment_825143) and Escherichia coli(contig Sediment_188430) carrying mex B and APH(3′)-IIa were found in sediments, and Laribacter hongkongensis(contig Water_478168 and Water_369477), Shigella sonnei(contig Water_880246),and Acinetobacter baumannii(contig Water_525520) carrying sul1, sul2, ere A, qac H, OXA-21, and mph D were found in pond water. Mobile genetic elements(MGEs) analysis indicated that horizontal gene transfer(HGT) of integrons, insertion sequences, and plasmids existed in shrimp intestine, sediment, and water samples, and the abundance of integrons was higher than that of other two MGEs. The results suggested that HPB carrying ARGs potentially existed in aquatic environments, and that these contributed to the environment and public health risk evaluation.  相似文献   
703.
广州城市环境地质问题   总被引:1,自引:0,他引:1  
方燎原 《地球与环境》2005,33(Z1):614-616
对广州市生态环境和地质环境的分析说明,诱发地质灾害主要是人为因素,有必要提高市民的地质灾害防范意识。  相似文献   
704.
Old growth mangroves in existing protected areas store more carbon than restored forests or plantations. Carbon storage in such forests has economic value independent of additionality, offering opportunities for policy makers to ensure their maintenance, and inclusion in climate change mitigation strategies. Mangrove forests of the Everglades National Park (ENP), South Florida, though protected, face external stressors such as hydrological alterations because of flooding control structures and agriculture impacts and saltwater intrusion as a result of increasing sea level rise. Moreover, decreased funding of Everglades’ restoration activities following the recent economic crisis (beginning 2008) threatens the restoration of the Greater Everglades including mangrove dominated coastal regions. We evaluate several economic and ecological challenges confronting the economic valuation of total (vegetation plus soil) organic carbon (TOC) storage in the ENP mangroves. Estimated TOC storage for this forested wetland ranges from 70 to 537 Mg C/ha and is higher than values reported for tropical, boreal, and temperate forests. We calculate the average abatement cost of C specific for ENP mangroves to value the TOC from $2–$3.4 billion; estimated unit area values are $13,859/ha–$23,728/ha. The valuation of the stored/legacy carbon is based on the: 1) ecogeomorphic attributes, 2) regional socio-economic milieu, and 3) status of the ENP mangroves as a protected area. The assessment of C storage estimates and its economic value can change public perception about how this regulating ecosystem service of ENP mangrove wetlands (144,447 ha) supports human well-being and numerous economic activities. This perception, in turn, can contribute to future policy changes such that the ENP mangroves, the largest mangrove area in the continental USA, can be included as a potential alternative in climate change mitigation strategies.  相似文献   
705.
以东莞市为例,运用环境经济学方法对“十一五”期间城市区域开发对生态系统服务功能的影响进行评价。2011年东莞市生态系统服务功能总价值约为25.44亿元,较2005年(31.20亿元)减少18.5%。气体调节、气候调节、水源涵养等9种生态系统服务功能价值均有不同程度的减少,其中水源涵养、废物处理和休闲娱乐3种生态系统服务功能的价值减少均超过20%。结果表明,东莞城市建设已经对区域生态系统服务功能造成了较大的影响,土地利用方式有待进一步优化。  相似文献   
706.
The nitrate-nitrogen(NO 3-N) concentrations from shallow groundwater wells situated in 29 of the Chinese Ecosystem Research Network field stations,representing typical agroand forest ecosystems,were assessed using monitoring data collected between 2004 and 2010.Results from this assessment permit a national scale assessment of nitrate concentrations in shallow groundwater,and allow linkages between nitrate concentrations in groundwater and broad land use categories to be made.Results indicated that most of the NO 3--N concentrations in groundwater from the agroand forest ecosystems were below the Class 3 drinking water standard stated in the Chinese National Standard:Quality Standard for Ground Water(≤ 20 mg/L).Over the study period,the average NO 3--N concentrations were significantly higher in agro-ecosystems(4.1 ± 0.33 mg/L) than in forest ecosystems(0.5 ± 0.04 mg/L).NO 3-N concentrations were relatively higher(> 10 mg N /L) in 10 of the 43 wells sampled in the agricultural ecosystems.These elevated concentrations occurred mainly in the Ansai,Yucheng,Linze,Fukang,Akesu,and Cele field sites,which were located in arid and semiarid areas where irrigation rates are high.We suggest that improvements in N fertilizer application and irrigation management practices in the arid and semi-arid agricultural ecosystems of China are the key to managing groundwater nitrate concentrations.  相似文献   
707.
为探讨沈阳市棋盘山水库湿地保护地近30年生态系统演变规律,文章运用3S技术和景观格局指数,分析了保护地1986~2015年生态系统时空变化及景观格局演变特征。结果表明:1986~2015年间,由于人类活动的干扰,保护地景观破碎度和空间异质性不断增加,水库周边建设用地围绕水库向南部、北部不断扩张,不利于生态系统服务功能的保护和提升,但总体上看,2000~2015年人类活动强度低于1986~2000年,说明该时期生态保护工作取得一定成效。为提升保护地景观质量和生态系统服务功能,提出了保护地生态系统服务可持续管理对策。  相似文献   
708.
Agricultural soils offer multiple soil functions, which contribute to a range of ecosystem services, and the demand for the primary production function is expected to increase with a growing world population. Other key functions on agricultural land have been identified as water purification, carbon sequestration, habitat biodiversity and nutrient cycling, which all need to be considered for sustainable intensification. All soils perform all functions simultaneously, but the variation in the capacity of soils to supply these functions is reviewed in terms of defined land use types (arable, bio-energy, broadleaf forest, coniferous forest, managed grassland, other grassland and Natura 2000) and extended to include the influence of soil drainage characteristics (well, moderately/imperfect, poor and peat). This latter consideration is particularly important in the European Atlantic pedo-climatic zone; the spatial scale of this review. This review develops a conceptual framework on the multi-functional capacity of soils, termed Functional Land Management, to facilitate the effective design and assessment of agri-environmental policies. A final functional soil matrix is presented as an approach to show the consequential changes to the capacity of the five soil functions associated with land use change on soils with contrasting drainage characteristics. Where policy prioritises the enhancement of particular functions, the matrix indicates the potential trade-offs for individual functions or the overall impact on the multi-functional capacity of soil. The conceptual framework is also applied by land use area in a case study, using the Republic of Ireland as an example, to show how the principle of multi-functional land use planning can be readily implemented.  相似文献   
709.
Ecosystem services support human livelihoods and economies but are declining in many places. Ecosystem service assessments estimate the benefits that nature provides to people and can be used to evaluate trade-offs in impacts and changes resulting from land use decisions. Such assessments can affect the capacity of decision-makers to make sustainable land use decisions, but the actual impact of such projects on decision-maker attitudes is almost entirely unstudied. We addressed this knowledge gap by evaluating the impact of an ecosystem service assessment on decision-makers in California. We asked how decision-makers’ understanding of and attitudes about ecosystem services changed “pre-” and “post-” assessments and between treatment groups where ecosystem services were assessed and a comparison group where ecosystem services were not assessed. Mixed methods included regression models to estimate the treatment effect of the assessment (using a difference-in-differences approach), as well as interviews and direct observations to further understand how decision-makers responded to the assessment. Regression results showed small increases relative to the comparison group in decision-maker understanding of ecosystem services and perceived relevance of ecosystem services to their work. Interviews confirmed that decision-makers learned specific ways that they could use ecosystem services in conservation and development decisions and believed that doing so would improve outcomes. These results demonstrate how ecosystem services assessments can facilitate a conceptual shift in the minds of decision-makers, which is a necessary ingredient for subsequent policy impact. Impact evaluation studies of this type − that estimate a counterfactual and explore rival explanations for observed outcomes − are needed to truly understand whether ecosystem service projects impact decision-makers and, ultimately, produce outcomes for environmental and human well-being.  相似文献   
710.
In this research we explored how the concepts and approaches of ecosystem services are currently used in water management in Europe, in the application of River Basin Management Plans (RBMP) developed for the EU Water Framework Directive (WFD). Five case studies have been considered, located in the River Basin Districts of the Po river (Italy), Scotland (United Kingdom), Scheldt river (Belgium), Danube river (Romania), Sado and Mira rivers and Ribeiras do Algarve (Portugal). These cases represent different regional contexts of application of this EU water policy, with specific socio-economic drivers and environmental issues. Each case study has developed an operational framework to analyse ecosystem services in practice together with a group of local stakeholders. In each regional case, we examined how EU water policy and RBMPs are implemented, considered legal and planning instruments from the national to the local scale, and we analysed the use of ecosystem service terms and concepts in the relevant planning instruments. In parallel, we explored the view of local stakeholders and water managers on the topic, collecting their opinion on three major aspects: the usefulness of the concepts and approaches of ecosystem services for WFD river basin management plans, the risks and benefits of their use, and the knowledge needs to put the concepts into practice. The major drawback of the ecosystem service approach seems to be the challenge for practitioners of understanding new concepts and methodologies, while the major advantages are that it highlights all the hidden benefits of a water body in good health and promotes multi-functionality and sustainability in water management. The results of this study provide a picture across Europe of the current use of the concepts of ecosystem services in the RBMP and relevant insight on the opinion of local stakeholders and water managers.  相似文献   
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