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991.
Thirty-three air samples were collected by high-volume samplers from May 2007 to June 2008 in the coastal area of southwest Taiwan and analyzed for total suspended particulates (TSP) and polycyclic aromatic hydrocarbons (PAHs). Concentrations of TSP and total PAHs ranged from 40.4 to 251 μg m(-3) and 1.86-56.4 ng m(-3), respectively. Except for joss paper burning during the religious celebration of Ghost Month, which resulted in the highest concentration of PAHs in the summer of 2007, a seasonal variation in total PAH concentration was observed over this study period, with the highest concentrations in winter and the lowest in summer. Because of the geographical and climatic characteristics of the sampling site, monsoon activities modulate the seasonal variations of PAHs. Diagnostic ratios showed that PAHs in the atmosphere of the Kaohsiung coastal area arose predominantly from vehicle emissions (mainly from diesel exhaust), joss paper burning, and coal/wood combustion. The results of hierarchical cluster analysis (HCA) and principal component analysis (PCA) indicated that the sampling days could be divided into three groups and that the major source identification of PAHs was the same as the identification by diagnostic ratios. In addition, the results of HCA and PCA suggest that the samples collected with a prevailing northerly or northeasterly wind direction contain both local emissions and those from neighboring sources. On the other hand, the cases related to westerly or northwesterly winds indicated that local emission was the major source for the sampling site. 相似文献
992.
Jssica Luiza S. Silva Marcela Tomaz Pontes de Oliveira Oswaldo Cruz-Neto Marcelo Tabarelli Ariadna Valentina Lopes 《Ambio》2021,50(4):884
Urbanization has rapidly increased in recent decades and the negative effects on biodiversity have been widely reported. Urban green areas can contribute to improving human well-being, maintaining biodiversity, and ecosystem services (e.g. pollination). Here we examine the evolution of studies on plant–pollinator interactions in urban ecosystems worldwide, reviewing also research funding and policy actions. We documented a significant increase in the scientific production on the theme in recent years, especially in the temperate region; tropical urban ecosystems are still neglected. Plant–pollinator interactions are threatened by urbanization in complex ways, depending on the studied group (plant or pollinator [generalist or specialist]) and landscape characteristics. Several research opportunities emerge from our review. Research funding and policy actions to pollination/pollinator in urban ecosystems are still scarce and concentrated in developed countries/temperate regions. To make urban green spaces contribute to the maintenance of biodiversity and the provision of ecosystem services, transdisciplinary approaches (ecological–social–economic–cultural) are needed.Electronic supplementary materialThe online version of this article (10.1007/s13280-020-01410-z) contains supplementary material, which is available to authorized users. 相似文献
993.
An approach based on spatial multicriteria analysis to map the nature conservation value of agricultural land 总被引:2,自引:0,他引:2
Geneletti D 《Journal of environmental management》2007,83(2):228-235
Knowledge of the nature conservation value of agricultural land provides a useful input to land-use planning. However, the scarcity of suitable data causes this component to rarely play a role. The paper proposes a methodology based on commonly available data to assess the nature conservation value of agricultural landscapes, and to generate cartographic results to be used as decision variables in planning. The approach relies on landscape ecological indicators and on the application of multicriteria analysis in a Geographical Information System (GIS) context. Four criteria were selected: the agricultural landscape type, the cover of vegetation remnants and marginal features, the length of forest-agriculture ecotones, and the proximity to nature reserves. These criteria were assessed directly or by means of specific indicators, generating maps that were subsequently aggregated through spatial multicriteria analysis. The approach was tested in an alpine area located in Trentino (northern Italy). 相似文献
994.
Alicia Pelegrina-López Francisco M. Ocaña-Peinado Ignacio Henares-Civantos José L. Rosúa-Campos 《Journal of Environmental Planning and Management》2018,61(1):124-142
Protected areas cannot be considered as elements isolated from the human groups that inhabit them. Consideration of the social factor is fundamental to guarantee the success of any management model. In this sense, analyzing the perception of people who live in protected areas can be a key tool for the formulation of proposals for improving the existing models. This article explores perceptions of local residents in the Sierra Nevada Protected Area in Southern Spain and identifies the socio-demographic factors that affect these perceptions. The main objective is to generate relevant data for the protected area management team. The recommendations we can offer entail a review of the communication plan and participatory strategy considering social differences in perceptions of the local population. 相似文献
995.
ABSTRACT: The Soil and Water Assessment Tool (SWAT) has been used for hydrologic analyses at various watershed scales. However, little is known about the model's performance in coastal watersheds. In this study SWAT was evaluated for its applicability in three Louisiana coastal watersheds: the Amite, Tickfaw, and Tangipahoa River watersheds. The model was calibrated with daily discharge from 1976 to 1977 and validated from 1979 to 1999 for the Amite and Tangipahoa and with daily discharge from 1979 to 1989 for the Tickfaw. Deviation of mean discharge and the Nash‐Sutcliffe model efficiency were used to evaluate model behavior. The study found that Manning's roughness coefficient for the main channel, SCS curve number, and soil evaporation compensation factor were the most sensitive parameters for these coastal watersheds. The Manning's roughness coefficient showed the greatest effect on the response time of surface runoff, suggesting the critical role of channel routing in hydrologic modeling for lowland watersheds. The SWAT model demonstrated an excellent performance, with Nash‐Sutcliffe efficiencies of 0.935, 0.940, and 0.960 for calibrations of the Amite, Tickfaw, and Tangipahoa watersheds, respectively, and of 0.851, 0.811, and 0.867 for validations. The modeling results demonstrate that SWAT is capable of simulating hydrologic processes for medium scale to large scale coastal lowland watersheds in Louisiana. 相似文献
996.
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
997.
自然资本是经济社会绿色可持续发展的必要保障,对其进行评估是维持区域生态系统平衡的重要内容。以矿区自然资本为视角,运用三维生态足迹模型,测算黄河流域山西矿区生态足迹深度与广度并分析其变化特征,进一步阐释矿区生态占用动态演变的作用机理。结果表明:黄河流域山西矿区人均生态赤字由2010年的4.40 hm2/人增至2016年的6.31 hm2/人,随后降至2019年的5.02 hm2/人,生态足迹与生态承载力的差距总体趋于缩小。2010—2019年,人均生态足迹广度大致呈递减趋势,由0.63 hm2/人降到0.47 hm2/人,而人均生态足迹深度呈现出先增后减的倒U型变化趋势。黄河流域山西矿区自然资本时空动态演变过程的驱动机制是由生态环境供给、资源禀赋、社会发展、经济增长、能源损耗以及煤炭污染等诸多因素共同作用的结果。其中,煤炭污染、能源损耗、资源禀赋和经济增长中的第二产业增加值与矿区自然资本占用动态演变呈正相关,生态环境供给、社会发展中的环境规制指数与其呈负相关。总之,黄河流域山西矿区生态足迹与生态承载力的差距趋于缩小,但生态占用赤字仍然存在。
相似文献998.
999.
天津滨海新区环境状况分析及对策建议 总被引:5,自引:0,他引:5
郝未宁 《城市环境与城市生态》1999,12(1):54-56
天津市滨海新区包括塘沽、汉沽、大港、开发区、保税区、是近年天津最大的经济增长点,是全市经济发展的新龙头。本文依据近年环境的监测结果,分析了滨海新区的环境现状和主要环境问题,在此基础上提出了实现了新区社会、经济发展与环境,资源保护相协调,走可持续发展之路的对策建议。 相似文献
1000.