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161.
三峡库区重庆段土壤保持服务时空分布格局研究 总被引:4,自引:0,他引:4
土壤保持是生态系统服务与功能的重要组成,在防止土壤侵蚀、减少径流泥沙与农业面源污染等方面具有至关重要的作用。以对国家生态安全具有重要作用的土壤保持生态功能区——三峡库区重庆段为研究区域,研究得到了2000~2013年时间序列区域土壤保持服务"流量"结果,结果表明:(1)三峡库区重庆段多年平均土壤保持量为604.39 t/hm~2·a,沿长江干流自西向东逐渐增强,区域差异显著;(2)三峡库区的土壤保持服务存在明显的垂直分异特征,随着高程的增加,以300 m与900 m为节点,出现递减-递增-递减的分段规律,与人类活动存在明显的相关关系;(3)增加森林覆被面积是改善区域土壤保持、减少水土流失的重要举措。同时,在三峡库区开展坡改梯工程,减少坡耕地的数量能够有效控制区域水土流失; 相似文献
162.
Baer SG Engle DM Knops JM Langeland KA Maxwell BD Menalled FD Symstad AJ 《Environmental management》2009,43(2):189-196
Vast areas of arable land have been retired from crop production and “rehabilitated” to improved system states through landowner
incentive programs in the United States (e.g., Conservation and Wetland Reserve Programs), as well as Europe (i.e., Agri-Environment
Schemes). Our review of studies conducted on invasion of rehabilitated agricultural production systems by nontarget species
elucidates several factors that may increase the vulnerability of these systems to invasion. These systems often exist in
highly fragmented and agriculturally dominated landscapes, where propagule sources of target species for colonization may
be limited, and are established under conditions where legacies of past disturbance persist and prevent target species from
persisting. Furthermore, rehabilitation approaches often do not include or successfully attain all target species or historical
ecological processes (e.g., hydrology, grazing, and/or fire cycles) key to resisting invasion. Uncertainty surrounds ways
in which nontarget species may compromise long term goals of improving biodiversity and ecosystem services through rehabilitation
efforts on former agricultural production lands. This review demonstrates that more studies are needed on the extent and ecological
impacts of nontarget species as related to the goals of rehabilitation efforts to secure current and future environmental
benefits arising from this widespread conservation practice. 相似文献
163.
Castello L Viana JP Watkins G Pinedo-Vasquez M Luzadis VA 《Environmental management》2009,43(2):197-209
Fishers and small-scale fisheries worldwide have been marginalized historically. Now it is clear that integrating fishers
in management processes is key to resource conservation, but it is less clear how to do it. Here, based on a literature review and new information, we present and analyze a case in which the participation
of fishers in the management process was crucial in recovering an overexploited small-scale fishery for the pirarucu (Arapaima spp.) in the Amazon Basin, Brazil. In 8 years of experimental management, from 1999 to 2006, the population of pirarucu increased
9-fold (from about 2200 to 20,650 individuals), harvest quotas increased 10-fold (from 120 to 1249 individuals), and fishers’
participation in the management process increased and they benefited from increased monetary returns. Additionally, the number
of communities conducting the management scheme increased from 4 in 1999 to 108 in 2006, following the demands of fishers
and regional government agencies. Based on our analysis, we suggest that the participation of fishers in the management of
other small-scale fisheries in the world can be improved by focusing on (1) applying the knowledge and skills of fishers in
resource monitoring and management, (2) bridging knowledge systems among all involved stakeholders, (3) collaborating with
fishers that are interested in, and capable of conducting, resource conservation schemes, and (4) conducting management under
conditions of uncertainty. 相似文献
164.
There is growing concern that recreational shoreline angling activity may negatively impact littoral and riparian habitats
independent of any direct or indirect influences of fish harvest or fishing mortality through mechanisms such as disturbance
(e.g., trampling, erosion) and pollution (e.g., littering). We sampled a suite of aquatic and terrestrial variables (i.e.,
water quality, aquatic and terrestrial macrophytes, soil compaction, anthropogenic refuse) at 14 high shoreline angling-activity
sites (identified by way of interviews with conservation officers and angling clubs) within an urban area (Ottawa, Canada).
For each high angling-activity site, a nearby corresponding low angling-activity site was sampled for comparison. We found
that the percentage of barren area and soil compaction were greater in areas of high angling activity compared with areas
that experienced relatively low angling activity. In addition, terrestrial and aquatic macrophyte density, height, and diversity
were lower at high angling-activity sites. Angling- and non-angling-related litter was present in large quantities at each
of the high angling-activity sites, and comparatively little litter was found at low angling-activity sites. Collectively,
these findings indicate that shoreline angling does alter the riparian environment, contributing to pollution and environmental
degradation in areas of high angling intensity. With growing interest in providing urban angling opportunities and in response
to increasing interest in developing protected areas and parks, a better understanding of the ecologic impacts of shoreline
angling is necessary to address multiuser conflicts, to develop angler outreach and educational materials, and to optimize
management of angling effort to maintain ecologic integrity of riparian and aquatic ecosystems. 相似文献
165.
Stamatis Zogaris Alcibiades N. Economou Panayotis Dimopoulos 《Environmental management》2009,43(4):682-697
Ecoregion delineations have gained increased attention in Europe, especially following the Water Framework Directive 2000/60/EC
(WFD), which provides the European Union’s first policy-relevant ecoregion map. However, the WFD’s ecoregions were created
through a minor adaptation of Illies’ (Limnofauna Europaea. Gustav Fisher Verlag, Stuttgart, 1967/1978) freshwater zoogeographic
regions, and the map’s specific boundaries have not been widely evaluated with respect to the WFD’s uses or their biogeographic
accuracy. We examined the WFD ecoregion boundaries in Greece and its neighboring Balkan states by comparing them with the
most prominent freshwater biogeographic boundaries as shown by riverine freshwater fish assemblages. Classification and ordination
analyses of 23 river basin fish assemblages helped delineate natural faunal break boundaries in freshwater species assemblage
distributions depicting major biogeographic barriers to aquatic biota dispersal. However, these biogeographic boundaries differ
from those delineated in the WFD map, suggesting boundary errors and inconsistencies in the delineation method of the WFD
ecoregions. We reviewed specific boundary disagreements and produced a map showing the region’s most prominent freshwater
biogeographic boundaries by charting them on watershed borders among the four biotically dissimilar river basin groups in
the southern Balkans. This regional evaluation reveals both a need to reconcile disparate approaches to ecoregion mapping
and to promote the development of a new policy-relevant inland waters ecoregion framework that would support broad-scale water
management and aquatic conservation. 相似文献
166.
Josephine A. Hagger Tamara S. Galloway Malcolm B. Jones 《Environmental pollution (Barking, Essex : 1987)》2009,157(7):2003-2010
A series of European Marine Sites has been designated as Special Areas of Conservation (SAC) in England. The aim of this study was to develop a practical methodology to assess the condition of SACs by applying a suite of biomarkers. Biomarkers were applied to the blue mussel Mytilus edulis and the shore crab Carcinus maenas from the Fal and Helford SAC (Cornwall). Individual biomarkers provided useful diagnostic information on the activity of certain classes of contaminants and an integrated Biomarker Response Index (BRI) was used to achieve a more holistic understanding of the condition of the SAC. The BRI indicated that the general health of both organisms was impacted in the upper part of the SAC (Fal Estuary) which correlated well with known chemical hotspots and sources of contamination. The BRI allows a pragmatic way to prioritise SAC sites that may require further investigative studies. 相似文献
167.
Govil PK Sorlie JE Murthy NN Sujatha D Reddy GL Rudolph-Lund K Krishna AK Rama Mohan K 《Environmental monitoring and assessment》2008,140(1-3):313-323
Studies on quantitative soil contamination due to heavy metals were carried out in Katedan Industrial Development Area (KIDA),
south of Hyderabad, Andhra Pradesh, India under the Indo-Norwegian Institutional Cooperation Programme. The study area falls
under a semi-arid type of climate and consists of granites and pegmatite of igneous origin belonging to the Archaean age.
There are about 300 industries dealing with dyeing, edible oil production, battery manufacturing, metal plating, chemicals,
etc. Most of the industries discharge their untreated effluents either on open land or into ditches. Solid waste from industries
is randomly dumped along roads and open grounds. Soil samples were collected throughout the industrial area and from downstream
residential areas and were analysed by X-ray Fluorescence Spectrometer for fourteen trace metals and ten major oxides. The
analytical data shows very high concentrations of lead, chromium, nickel, zinc, arsenic and cadmium through out the industrial
area. The random dumping of hazardous waste in the industrial area could be the main cause of the soil contamination spreading
by rainwater and wind. In the residential areas the local dumping is expected to be the main source as it is difficult to
foresee that rain and wind can transport the contaminants from the industrial area. If emission to air by the smokestacks
is significant, this may contribute to considerable spreading of contaminants like As, Cd and Pb throughout the area. A comparison
of the results with the Canadian Soil Quality Guidelines (SQGL) show that most of the industrial area is heavily contaminated
by As, Pb and Zn and local areas by Cr, Cu and Ni. The residential area is also contaminated by As and some small areas by
Cr, Cu, Pb and Zn. The Cd contamination is detected over large area but it is not exceeding the SQGL value. Natural background
values of As and Cr exceed the SQGL values and contribute significantly to the contamination in the residential area. However,
the availability is considerably less than anthropogenic contaminants and must therefore be assessed differently. The pre-
and post-monsoon sampling over two hydrological cycles in 2002 and 2003 indicate that the As, Cd and Pb contaminants are more
mobile and may expect to reach the groundwater. The other contaminants seem to be much more stable. The contamination is especially
serious in the industrial area as it is housing a large permanent residing population. The study not only aims at determining
the natural background levels of trace elements as a guide for future pollution monitoring but also focuses on the pollution
vulnerability of the watershed. A plan of action for remediation is recommended. 相似文献
168.
吴淞工业区大气降尘变化规律及趋势 总被引:2,自引:1,他引:1
吴淞工业区是重工业聚集区,烟(粉)尘的排放量非常大,造成该地区空气污染严重.为了解降尘的污染特征、变化规律及趋势,以近10 a监测数据为依据,运用方差分析等数理统计方法对工业区降尘量进行分析,检验不同季节降尘的差异并简要分析原因,使用秩相关系数法对其进行趋势分析.结果表明,工业区降尘量较混合区与清洁区明显不同; 工业区与混合区的降尘受本地源的影响较大,4季的降尘量没有明显差异,相反清洁区的4季降尘呈显著差异.10 a来工业区及其周边地区的降尘量下降了56%,说明环境综合整治取得了显著效果,使区域环境空气质量得到改善. 相似文献
169.
This article develops a methodology aimed at generating a systematic social diagnosis of social and natural landscapes. The analytical process is divided into six easily replicable and causatively connected steps. The goal is two-fold: first, to present the inextricable connections between physical landscapes and the communities that occupy them. And second, to provide a fundamental tool to public policy designers that should simultaneously improve social acceptability of conservation policies and policy efficiency and effectiveness. Finally, this methodology is consciously heterogeneous from a theoretical perspective. This article puts together, in fruitful dialogue, contributions from varying places on the social theory spectrum: from political economy to poststructural theory. 相似文献
170.
This research investigates whether species are perceived differently based on aesthetic and negativistic attitudes, and whether these and other attitudes, naturalistic activities, and gender predict support for the protection of threatened species. 228 undergraduate students completed a survey in which they rated pictures of 10 endangered species on aesthetic and negativistic attitudes, and support for protection. Findings showed that the two-striped garter snake, Ozark big-eared bat, and dolloff cave spider were conceptualized differently than other species, which may be the result of “irrational” fears linked to animal phobias, culture, and emotional reactions to pictures. The regression results support the common belief that aesthetics is an important determinant in perceptions of endangered species and that the importance of negativistic attitudes may be waning. Moralistic worldviews and attitudes toward landowner rights and the Endangered Species Act were significantly related to support for governmental protection of species. Surprisingly, naturalistic activities and gender were not significantly associated with support for governmental protection of species. In general, the results were consistent across both models. However, the amount of variance explained by aesthetic and negativistic attitudes was 23 percent higher in the other species models than in the bat, snake, and spider models. 相似文献