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761.
The management of small-scale freshwater fisheries in Amazon has been based usually on surveys of urban markets, while fisheries
of rural villages have gone unnoticed. We compared the fishing characteristics (catch, effort and selectivity) between an
urban market and five small villages in the Lower Tocantins River (Brazilian Amazon), downstream from a large reservoir. We
recorded 86 and 601 fish landings in the urban market and villages, respectively, using the same methodology. The urban fishers
showed higher catch per unit of effort, higher amount of ice (related to a higher fishing effort, as ice is used to store
fish catches) and larger crew size per fishing trip, but village fishers had a higher estimated annual fish production. Conversely,
urban and village fishers used similar fishing gear (gillnets) and the main fish species caught were the same. However, village
fishers showed more diverse strategies regarding gear, habitats and fish caught. Therefore, although it underestimated the
total amount of fish caught in the Lower Tocantins River region, the data from the urban market could be a reliable indicator
of main fish species exploited and fishing gear used by village fishers. Monitoring and management should consider the differences
and similarities between urban and rural fisheries, in Amazon and in other tropical regions. 相似文献
762.
Rosenfeld J Hogan D Palm D Lundquist H Nilsson C Beechie TJ 《Environmental management》2011,47(1):28-39
Sediment size and supply exert a dominant control on channel structure. We review the role of sediment supply in channel structure,
and how regional differences in sediment supply and landuse affect stream restoration priorities. We show how stream restoration
goals are best understood within a common fluvial geomorphology framework defined by sediment supply, storage, and transport.
Landuse impacts in geologically young landscapes with high sediment yields (e.g., coastal British Columbia) typically result
in loss of instream wood and accelerated sediment inputs from bank erosion, logging roads, hillslopes and gullies. In contrast,
northern Sweden and Finland are landscapes with naturally low sediment yields caused by low relief, resistant bedrock, and
abundant mainstem lakes that act as sediment traps. Landuse impacts involved extensive channel narrowing, removal of obstructions,
and bank armouring with boulders to facilitate timber floating, thereby reducing sediment supply from bank erosion while increasing
export through higher channel velocities. These contrasting landuse impacts have pushed stream channels in opposite directions
(aggradation versus degradation) within a phase-space defined by sediment transport and supply. Restoration in coastal British
Columbia has focused on reducing sediment supply (through bank and hillslope stabilization) and restoring wood inputs. In
contrast, restoration in northern Fennoscandia (Sweden and Finland) has focused on channel widening and removal of bank-armouring
boulders to increase sediment supply and retention. These contrasting restoration priorities illustrate the consequences of
divergent regional landuse impacts on sediment supply, and the utility of planning restoration activities within a mechanistic
sediment supply-transport framework. 相似文献
763.
The Fate of Priority Areas for Conservation in Protected Areas: A Fine-Scale Markov Chain Approach 总被引:1,自引:0,他引:1
Park managers in alpine areas must deal with the increase in forest coverage that has been observed in most European mountain
areas, where traditional farming and agricultural practices have been abandoned. The aim of this study is to develop a fine-scale
model of a broad area to support the managers of Paneveggio Nature Park (Italy) in conservation planning by focusing on the
fate of priority areas for conservation in the next 50–100 years. GIS analyses were performed to assess the afforestation
dynamic over time using two historical maps (from 1859 and 1936) and a series of aerial photographs and ortho-photos (taken
from 1954 to 2006) covering a time span of 150 years. The results show an increase in the forest surface area of about 35%.
Additionally, the forest became progressively more compact and less fragmented, with a consequent loss of ecotones and open
habitats that are important for biodiversity. Markov chain-cellular automata models were used to project future changes, evaluating
the effects on a habitat scale. Simulations show that some habitats defined as priority by the EU Habitat Directive will be
compromised by the forest expansion by 2050 and suffer a consistent loss by 2100. This protocol, applied to other areas, can
be used for designing long-term management measures with a focus on habitats where conservation status is at risk. 相似文献
764.
This article examines one MPA—the Gulf of Mannar National Park and Biosphere Reserve—located in southern India, and four types
of social conflict that have surrounded its establishment. Taking the strength of wellbeing aspirations as point of departure,
we focus on two themes: the implications of MPA embeddedness in wider societal systems, and the consequences of natural and
social variety for governance. We conclude first of all that conflict resolution depends on MPA authorities’ willingness to
engage with the interferences that emerge from outside the MPA area. Secondly, we point out the varying wellbeing aspirations
of the population and the need to develop governance partnerships. The latter are argued to contribute to more balanced decision
making, as well as to a greater appreciation among the target population of the ‘fairness’ of MPA policy. 相似文献
765.
Cetacean-focused tourism in Taiwan has grown rapidly since 1997. This development, measured in terms of both number of tour
boats and visitors, has resulted in many resource management challenges stemming from the absence of regulation and scientific
data. To fill this void in empirical evidence, we used 464 sighting records from 2002 to 2005 to model the impact of cetacean-focused
tourism. Cox proportional hazard analysis indicated cetacean avoidance responses to cetacean watching boats were strongly
associated with pod size, mother–calf pairs, and cetacean-vessel distances. Mother–calf pairs abandoned their avoidance tactic
by 55% compared to noncalf groups when tour boats approached. Second, the hazard ratio of abundance was 0.996, suggesting
that the odds of encountering avoidance responses by the cetaceans decreased by 42% for every 100-member increase in the cetacean
pod size. Last, distances maintained by boats from the cetaceans was positively related to avoidance responses (i.e., less
avoidance behavior with closer interaction). Based on our findings, we have the following recommendations: (a) limit vessels
from approaching mothers with calves, (b) limit vessels from approaching small groups of cetaceans, (c) reduced avoidance
behavior to boat traffic may be a red flag for potential long-term disturbance, and (d) apply the “precautionary principle”
based on the best scientific information available in cetacean-based tourism in Taiwan. These recommendations will help contribute
to the sustainable development of cetacean-focused tourism in Taiwan. 相似文献
766.
Throughout the world there is a general consensus among environmentalists that there should be an increase in the amount of
marine area that should be reserved in marine protected areas (MPAs). In fact, the 1998 Philippines Fishery Code indicates
a need for designation of at least 15% of municipal waters for fish refuges or sanctuaries. Such an increase in area would
take productive fishing areas away from fishing communities that can ill-afford the loss. The larger the protected area, there
will be a greater number of people impacted. This article examines the relationship between factors that influence the success
of Community Based MPA (CBMPA) performance in the Visayas, Philippines and their significance in efforts to increase the size
of protected areas. 相似文献
767.
As the number of marine protected areas (MPAs) is globally increasing, information is needed on the effectiveness of existing
sites. Many protected area agencies however have limited resources and are unable to evaluate MPA effectiveness. An evaluation
conducted entirely by the managing agency may also lack credibility. Long-term monitoring and evaluation programs should ideally
offer opportunities for participation of diverse groups in the selection of evaluation indicators and their assessment. A
participatory approach has the potential to enhance evaluation capacity, to increase credibility and acceptance of results,
to strengthen relationships between managers and local stakeholders, and to address more locally relevant information. Using
a case study approach, this paper investigates diverse stakeholder groups’ opinions on the design of an evaluation and their
interest to participate in an assessment. Respondents were most interested in the assessment of MPA achievements and outcome
indicators. Most groups identified a range of government agencies and stakeholders that should participate in an assessment
but only half of all respondents were interested to participate in monitoring activities. Most frequently mentioned limitations
for more participation were a lack of time and money, but also governance shortcomings such as limited participation possibilities
and not paying enough credit to stakeholders’ input. Participation interest was also influenced by occupation, place of residency,
and familiarity with the marine environment. Differences exist among stakeholders about suitable evaluators and preferred
monitoring partners, which could affect the credibility of evaluation results and affect monitoring activities. 相似文献
768.
Merle Sowman Maria Hauck Lance van Sittert Jackie Sunde 《Environmental management》2011,47(4):573-583
A historical perspective on MPA identification and governance in South Africa reflects the continued influence of a top-down
and natural science-based paradigm, that has hardly changed over the past half century, despite the wealth of literature,
and a growing consensus, that advocates the need to adopt a more integrated and human-centered approach. Based on extensive
research in two coastal fishing communities, the paper highlights impacts and conflicts arising from this conventional approach
to MPA identification, planning and management. It argues that failure to understand the particular fishery system in all
its complexity, in particular the human dimensions, and involve resource users in planning and decision-making processes,
undermines efforts to achieve conservation and fisheries management objectives. The customary rights of local resource users,
and their food and livelihood needs in relation to marine resources, need to be acknowledged, prioritized and integrated into
planning and decision-making processes. Convincing ecologists, fisheries scientists and managers, that MPA success depends
on addressing the root causes of resource decline and incorporating social factors into MPA identification, planning and management,
remains a huge challenge in South Africa. 相似文献
769.
Many alpine ski areas have recently adopted voluntary environmental programs (VEPs) such as using recycling, renewable energy,
and biofuels to help reduce their environmental impacts. Studies have addressed the performance of these VEPs in mitigating
environmental impacts of this industry, but little is known about visitor awareness and perceptions of these programs. This
article addresses this knowledge gap by exploring skier and snowboarder knowledge of VEPs at a ski area and the influence
of these programs on their motivations to visit this area currently and behavioral intentions to visit again in the future.
Data were obtained from an onsite survey at the Mt. Bachelor ski area in Oregon, USA (n = 429, 89.7% response rate). Few skiers and snowboarders were knowledgeable of VEPs at this area and fewer than 20% were
motivated to visit on their current trip because of these programs. Other attributes such as scenery, snow conditions, and
access were more important for influencing visitation. Up to 38% of skiers and snowboarders, however, intend to visit this
ski area more often if it adopts and promotes more VEPs. Managers can use these results to inform communication and marketing
of their environmental programs and performance to visitors. Additional implications for management and future research are
discussed. 相似文献
770.
Mohammad Aslam Khan S. Akhtar Ali Shah 《Journal of Agricultural and Environmental Ethics》2011,24(5):493-509
There is evidence of continued food insecurity and malnutrition in Pakistan despite significant progress made in terms of
food production in recent years. According to “Vision 2030” of the Planning Commission of Pakistan, about half of the population
in the country suffers from absolute to moderate malnutrition, with the most vulnerable being children, women, and elderly
among the lowest income group. The Government of Pakistan has been taking a series of policy initiatives and strategic measures
to combat food insecurity issues. These range from increasing production to food imports, implementation of poverty reduction
strategies, nutritional improvement programs, as well as provision of social safety nets. The article aims to instill some
fresh thinking into the debate regarding the challenges of food security. It underscores the limitations of hitherto policy
response, and suggests crucial measures to improve the present grim scenario. Policy makers, planners, practitioners, and
academicians in countries with comparable socio-political and economic setup can view this discussion as a case study and
may apply the findings in their domain accordingly. 相似文献