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1.
Tiziano Gomiero Mario Giampietro Sandra G. F. Bukkens Maurizio G. Paoletti 《Critical Reviews in Plant Sciences》1999,18(3):359-371
In this article, we provide an overview, on freshwater fish aquaculture in P.R. China, with special emphasis on pond fish culture. We describe the history, ecology (trophic structure and species reared), and technological aspects (including inputs/outputs, yields, labor productivity, and fossil energy use) of freshwater fish production and analyze its role in relation to the socioeconomic context. We discuss the prospects for intensification of production. In China, freshwater fish aquaculture has always been closely linked to cultivation of crops and animal husbandry, that is, feed inputs are in the form of agricultural wastes. The close integration with the farming system at large results in an efficient use of nutrients, low environmental loading, and little dependence on fossil energy inputs. About 7 to 9 different fish species, mainly herbivores, are kept in the same pond and efforts are made to maintain as much as possible the natural mechanisms of matter regulation and energy flows within the pond ecosystem. However, ecological compatibility is paid for by relatively low productivity, both per hectare of waterbody and per hour of labor input. If the throughput of freshwater fish production per unit of area and labor are to be dramatically increased, the equilibrium of the traditional integrated system will be difficult to maintain. 相似文献
2.
Humanity's dependence on ecosystem support is “mentally hidden” to large segments of society; it has no price in the market
and is seldom accounted for in decision making. Similarly, the needs of ecosystems for fresh water for generation of nature's
services are largely invisible. Freshwater assessments predominantly have focused on human uses of liquid water in rivers,
lakes, and reservoirs. We estimated the spatial appropriation of terrestrial and marine ecosystems—the ecological footprint—of
the 85 million inhabitants in the Baltic Sea drainage basin with regard to consumption of food and timber and waste assimilation
of nutrients and carbon dioxide. We also estimated the amount of fresh water—the water vapor flow—that the inhabitants depend
upon for their appropriation of these ecosystem services. The ecological footprint estimate corresponds to an area as large
as 8.5–9.5 times the Baltic Sea and its drainage basin with a per capita ecosystem appropriation of 220,000–250,000 m2. This large estimate is mainly attributed to carbon sequestering by marine ecosystems and forests. The water vapor flow of
the ecological footprint of forests, wetlands, agriculture, and inland water bodies for making the human appropriation of
ecosystem services possible is estimated at 1175–2875 km3 y−1. Human dependence on water vapor flows for ecosystem services is as great as 54 times the amount of freshwater runoff that
is assessed and managed in society. Decision making on an increasingly human-dominated planet will have to address explicitly
the critical interdependencies between freshwater flows and the capacity of ecosystems to generate services. We advocate a
dynamic ecohydrological landscape-management approach upstream and downstream in watersheds to reduce unintentional impacts,
irreversible change, and further loss of freshwater resources, ecosystem services, and resilience.
Received 6 October 1998; accepted 30 March 1999. 相似文献
3.
Land-Use History in Ecosystem Restoration: A 40-Year Study in the Prairie-Forest Ecotone 总被引:4,自引:0,他引:4
W. Dean Kettle Paul M. Rich Kelly Kindscher Galen L. Pittman Pinde Fu 《Restoration Ecology》2000,8(3):307-317
Land‐use history, recent management, and landscape position influence vegetation at the Rockefeller Experimental Tract (RET), a 40‐year‐old restoration experiment in northeast Kansas. RET is representative of the prairie‐forest ecotone, containing native tallgrass prairie and oak‐hickory forest, but unique in having tracts of replanted prairie, seeded in 1957, that have undergone long‐term restoration treatments: burned, grazed, mowed, or untreated. A land‐use history database for RET was compiled using a geographic information system to integrate historic and contemporary sources of information. Restoration management on the reseeded prairie has had a profound effect on forest development: mowing or burning precluded forest establishment (<3% forest cover), whereas portions of untreated or grazed areas became heavily forested (>97% forest cover). Forest colonization depends upon biotic and edaphic conditions at the time restoration was initiated: for areas replanted to prairie and managed by grazing, forestation was 6% on land in cultivation prior to replanting, 20% on former pastureland, and 98% on land deforested just before replanting. Patterns of forest colonization were also significantly associated with three landscape positions: near existing forest, along water courses, and along ridge tops. Additionally, land‐use history analyses showed that the presence of various prairie and forest species resulted from persistence and not from colonization following restoration. Because of the lasting imprint of historic land use on the landscape, our results indicate that it is essential that restoration studies be evaluated within a site‐specific historical context. 相似文献
4.
《Journal of Industrial Ecology》2004,8(1-2):193-221
Remanufacturing restores used automotive engines to like-new condition, providing engines that are functionally equivalent to a new engine at much lower environmental and economic costs than the manufacture of a new engine. A life-cycle assessment (LCA) model was developed to investigate the energy savings and pollution prevention that are achieved in the United States through remanufacturing a midsized automotive gasoline engine compared to an original equipment manufacturer manufacturing a new one. A typical full-service machine shop, which is representative of 55% of the engine remanufacturers in the United States, was inventoried, and three scenarios for part replacement were analyzed. The life-cycle model showed that the remanufactured engine could be produced with 68% to 83% less energy and 73% to 87% fewer carbon dioxide emissions. The life-cycle model showed significant savings for other air emissions as well, with 48% to 88% carbon monoxide (CO) reductions, 72% to 85% nitrogen oxide (NOx) reductions, 71% to 84% sulfur oxide (SOx) reductions, and 50% to 61% nonmethane hydrocarbon reductions. Raw material consumption was reduced by 26% to 90%, and solid waste generation was reduced by 65% to 88%. The comparison of environmental burdens is accompanied by an economic survey of suppliers of new and remanufactured automotive engines showing a price difference for the consumer of between 30% and 53% for the remanufactured engine, with the greatest savings realized when the remanufactured engine is purchased directly from the remanufacturer. 相似文献
5.
Response of Microorganisms to an Accidental Gasoline Spillage in an Arctic Freshwater Ecosystem 总被引:1,自引:2,他引:1
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The response of microorganisms to an accidental spillage of 55,000 gallons of leaded gasoline into an Arctic freshwater lake was studied. Shifts in microbial populations were detected after the spillage, reflecting the migration pattern of the gasoline, enrichment for hydrocarbon utilizers, and selection for leaded-gasoline-tolerant microorganisms. Ratios of gasoline-tolerant/utilizing heterotrophs to “total” heterotrophs were found to be a sensitive indicator of the degree of hydrocarbon contamination. Respiration rates were elevated in the highly contaminated area, but did not reflect differences between moderately and lightly contaminated areas. Hydrocarbon biodegradation potential experiments showed that indigenous microorganisms could extensively convert hydrocarbons to CO2. In situ measurement of gasoline degradation showed that, if untreated, sediment samples retained significant amounts of gasoline hydrocarbons including “volatile components” at the time the lake froze for the winter. Nutrient addition and bacterial inoculation resulted in enhanced biodegradative losses, significantly reducing the amount of residual hydrocarbons. Enhanced biodegradation, however, resulted in the appearance of compounds not detected in the gasoline. Since the contaminated lake serves as a drinking water supply, treatment to enhance microbial removal of much of the remaining gasoline still may be advisable. 相似文献
6.
Environmental Indication: A Field Test of an Ecosystem Approach to Quantify Biological Self-Organization 总被引:3,自引:0,他引:3
Werner L. Kutsch Wolf Steinborn Mathias Herbst Rainer Baumann Jan Barkmann Ludger Kappen 《Ecosystems》2001,4(1):49-66
In this study, we take an ecosystem approach to examine the degree of biological self-organization at the ecosystem level. An integrated set of indicators is derived from a theoretical framework and tested by field data from an ecosystem research project focusing on the Bornhöved Lake district in northern Germany. This field test is based on a comparison of the self-organized phenomena that comprise the carbon, water, and energy budgets of two adjacent edaphically and climatically similar ecosystems, that have vastly different levels of human interference—a crop field and a beech forest. In terms of biomass storage, biologically incorporated nitrogen and phosphorus, species number, total ecosystem respiration per total biomass (qCO2), total ecosystem assimilation per available nutrients, and transpiration per total evapotranspiration, we found clear differences between the systems. Ecosystem surface temperature and Rn/K* were found to be of limited utility in characterizing the two systems. The study is rooted in the concept of ecological integrity, an influential idea at the interface of ecological and environmental debate that has acquired a number of different meanings. Among other interpretations, it can be viewed as a guiding principle for sustainable land use that aims at long-term protection of ecological life-support systems. Effective use of any interpretation of this concept requires a theoretically consistent and applicable set of indicators. Therefore, we also discuss the integration of the indicator set and its potential use in monitoring programs. 相似文献
7.
Ecosystem Services and Emergent Vulnerability in Managed Ecosystems: A Geospatial Decision-Support Tool 总被引:2,自引:0,他引:2
Managed ecosystems experience vulnerabilities when ecological resilience declines and key flows of ecosystem services become depleted or lost. Drivers of vulnerability often include local management actions in conjunction with other external, larger-scale factors. To translate these concepts to management applications, we developed a conceptual model of feedbacks linking the provision of ecosystem services, their use by society, and anthropogenic change. From this model we derived a method to integrate existing geodata at relevant scales and in locally meaningful ways to provide decision-support for adaptive management efforts. To demonstrate our approach, we conducted a case study assessment of southeast Alaska, where managers are concerned with sustaining fish and wildlife resources in areas where intensive logging disturbance has occurred. Individual datasets were measured as indicators of one of three criteria: ecological capacity to support fish/wildlife populations (provision); human acquisition of fish/wildlife resources (use); and intensity of logging and related land-use change (disturbance). Relationships among these processes were analyzed using two methods—a watershed approach and a high-resolution raster—to identify where provision, use and disturbance were spatially coupled across the landscape. Our results identified very small focal areas of social-ecological coupling that, based on post-logging dynamics and other converging drivers of change, may indicate vulnerability resulting from depletion of ecosystem services. We envision our approach can be used to narrow down where adaptive management might be most beneficial, allowing practitioners with limited funds to prioritize efforts needed to address uncertainty and mitigate vulnerability in managed ecosystems. 相似文献
8.
Sean Maroongroge Simon P. Kim Sarah Mougalian Kimberly Johung Roy H. Decker Pamela R. Soulos Jessica B. Long Cary P. Gross James B. Yu 《The Yale journal of biology and medicine》2015,88(2):107-114
Although physician services represent a substantial portion of cancer care costs, little is known about trends in the costs of physician cancer services in the fee-for-service Medicare program. We analyzed aggregated data from all Part B Medicare claims for physician and supplier services attributed to cancer patients from 1999 to 2012 to characterize how billing and payments have changed over time for the most common cancer types. Billing and expenditure data are from the Medicare Statistical Supplement, and age-adjusted incidence data are from SEER. Physician services for cancer patients grew from $7.6 billion in 1999 to $12.3 billion in 2012 (60 percent increase). Reimbursements for physician and supplier services for cancer treatment in Medicare Part B beneficiaries steadily grew from 1999 to 2005 and then plateaued through 2012, led by a decrease in reimbursements for prostate cancer care. These trends may reflect shifts toward hospital-based care or changes in aggressiveness of care. 相似文献
9.
Tereza C. Giannini Leandro R. Tambosi André L. Acosta Rodolfo Jaffé Antonio M. Saraiva Vera L. Imperatriz-Fonseca Jean Paul Metzger 《PloS one》2015,10(6)
Ecosystem services provided by mobile agents are increasingly threatened by the loss and modification of natural habitats and by climate change, risking the maintenance of biodiversity, ecosystem functions, and human welfare. Research oriented towards a better understanding of the joint effects of land use and climate change over the provision of specific ecosystem services is therefore essential to safeguard such services. Here we propose a methodological framework, which integrates species distribution forecasts and graph theory to identify key conservation areas, which if protected or restored could improve habitat connectivity and safeguard ecosystem services. We applied the proposed framework to the provision of pollination services by a tropical stingless bee (Melipona quadrifasciata), a key pollinator of native flora from the Brazilian Atlantic Forest and important agricultural crops. Based on the current distribution of this bee and that of the plant species used to feed and nest, we projected the joint distribution of bees and plants in the future, considering a moderate climate change scenario (following IPPC). We then used this information, the bee’s flight range, and the current mapping of Atlantic Forest remnants to infer habitat suitability and quantify local and regional habitat connectivity for 2030, 2050 and 2080. Our results revealed north to south and coastal to inland shifts in the pollinator distribution during the next 70 years. Current and future connectivity maps unraveled the most important corridors, which if protected or restored, could facilitate the dispersal and establishment of bees during distribution shifts. Our results also suggest that coffee plantations from eastern São Paulo and southern Minas Gerais States could suffer a pollinator deficit in the future, whereas pollination services seem to be secured in southern Brazil. Landowners and governmental agencies could use this information to implement new land use schemes. Overall, our proposed methodological framework could help design novel conservational and agricultural practices that can be crucial to conserve ecosystem services by buffering the joint effect of habitat configuration and climate change. 相似文献
10.
Ecological risk assessment (ERA) is a scientific tool used to support ecosystem-based management (EBM), but most current ERA methods consider only a few indices of particular species or components. Such limitations restrict the scope of results so that they are insufficient to reflect the integrated risk characterization of an ecosystem, thereby inhibiting the application of ERA in EBM. We incorporate the concept of ecosystem services into ERA and develop an improved ERA framework to create a comprehensive risk map of an ecosystem, accounting for multiple human activities and ecosystem services. Using the Yellow River as a case study, we show how this framework enables the implementation of integrated risk characterization and prioritization of the most important ecological risk issues in the ecosystem-based river management of the Yellow River. This framework can help practitioners facilitate better implementation of ERA within EBM in rivers or any target ecosystem. 相似文献
11.
Effect of Degradation Intensity on Grassland Ecosystem Services in the Alpine Region of Qinghai-Tibetan Plateau,China 总被引:1,自引:0,他引:1
Lu Wen Shikui Dong Yuanyuan Li Xiaoyan Li Jianjun Shi Yanlong Wang Demei Liu Yushou Ma 《PloS one》2013,8(3)
The deterioration of alpine grassland has great impact on ecosystem services in the alpine region of Qinghai-Tibetan Plateau. However, the effect of grassland degradation on ecosystem services and the consequence of grassland deterioration on economic loss still remains a mystery. So, in this study, we assessed four types of ecosystem services following the Millennium Ecosystem Assessment classification, along a degradation gradient. Five sites of alpine grassland at different levels of degradation were investigated in Guoluo Prefecture of Qinghai Province, China. The species composition, aboveground biomass, soil total organic carbon (TOC), and soil total nitrogen (TN) were tested to evaluate major ecological services of the alpine grassland. We estimated the value of primary production, carbon storage, nitrogen recycling, and plant diversity. The results show the ecosystem services of alpine grassland varied along the degradation gradient. The ecosystem services of degraded grassland (moderate, heavy and severe) were all significantly lower than non-degraded grassland. Interestingly, the lightly degraded grassland provided more economic benefit from carbon maintenance and nutrient sequestration compared to non-degraded. Due to the destruction of the alpine grassland, the economic loss associated with decrease of biomass in 2008 was $198/ha. Until 2008, the economic loss caused by carbon emissions and nitrogen loss on severely degraded grassland was up to $8 033/ha and $13 315/ha, respectively. Urgent actions are required to maintain or promote the ecosystem services of alpine grassland in the Qinghai-Tibetan Plateau. 相似文献
12.
13.
Objective
According to policy commentators, decisions about how best to organise care involve trade-offs between factors relating to care quality, workforce, cost, and patient access. In England, proposed changes such as Emergency Department closures often face public opposition. This study examined the way communities respond to plans aimed at reorganising emergency services, including the trade-offs inherent in such decisions.Design
Cross-sectional study involving in-depth interviews. Participants selected their priorities for emergency care, including aspects they might be prepared to have ‘less’ of (e.g. rapid access) if it meant having ‘more’ of another (e.g. consultant-delivered care). A thematic analysis was carried out, combining inductive and deductive approaches, drawing on theories about risk perception.Setting
Two urban areas of England; one where changes to emergency services were under consideration (‘Greenville’), and one where they were not (‘Hilltown’).Participants
28 participants in total. Greenville interviewees included more common emergency service users - parents of young children (n=5) and older people (n=6) - plus patient representatives and individuals campaigning against service closures (n=9). Hilltown interviewees (n=8) received outpatient care for Chronic Obstructive Pulmonary Disease, an important cause of emergency admission.Results
Most participants, in both areas, were not willing to accommodate the trade-offs involved in consolidating emergency services, principally because of the belief that timely access is associated with better outcomes. Participants did not consider the proposed improvements as gains worth having; interviewees believed care quality would be adversely impact, partly because increased patient numbers would place staff under greater pressure and result in longer waiting times.Conclusions
Visible clinical leadership and detailed explanation of the case for change were insufficient to overcome opposition to the reconfiguration in Greenville, challenging the assumption that communities can be persuaded by evidence. Commissioners should make explicit credible plans to accommodate changes in patient flows, as well as clarifying the roles played by key staff groups. 相似文献14.
15.
David M Lansing 《Human ecology: an interdisciplinary journal》2017,45(1):77-87
This paper uses household survey data to examine factors associated with smallholder households that enroll in Costa Rica’s longstanding payments for ecosystem services (PES) program. To date, most evaluations of this sort have focused on larger landowners. Results from this study show that smallholders enrolled in PES tend to be older, wealthier, and have access to non-farm salaried income. These features match enrollment patterns of larger landowners in that enrollees tend to be relatively wealthy and only marginally engaged in agriculture. In addition, smallholders on state agrarian reform lands are significantly less likely to enroll in PES. These results indicate that targeting PES toward smaller landowners does not necessarily equate to a policy that reaches the rural poor, and suggests that further work is needed to address the access barriers to this program for economically marginal landowners. 相似文献
16.
Forecasting Environmental Responses to Restoration of Rivers Used as Log Floatways: An Interdisciplinary Challenge 总被引:1,自引:0,他引:1
Christer Nilsson Fabio Lepori Björn Malmqvist Erik Törnlund Niclas Hjerdt James M. Helfield Daniel Palm Johan Östergren Roland Jansson Eva Brännäs Hans Lundqvist 《Ecosystems》2005,8(7):779-800
Log floating in the 19th to mid 20th centuries has profoundly changed the environmental conditions in many northern river
systems of the world. Regulation of flow by dams, straightening and narrowing of channels by various piers and wing dams,
and homogenization of bed structure are some of the major impacts. As a result, the conditions for many riverine organisms
have been altered. Removing physical constructions and returning boulders to the channels can potentially restore conditions
for these organisms. Here we describe the history of log driving, review its impact on physical and biological conditions
and processes, and predict the responses to restoration. Reviewing the literature on comparable restoration efforts and building
upon this knowledge, using boreal Swedish rivers as an example, we address the last point. We hypothesize that restoration
measures will make rivers wider and more sinuous, and provide rougher bottoms, thus improving land-water interactions and
increasing the retention capacity of water, sediment, organic matter and nutrients. The geomorphic and hydraulic/hydrologic
alterations are supposed to favor production, diversity, migration and reproduction of riparian and aquatic organisms. The
response rates are likely to vary according to the types of processes and organisms. Some habitat components, such as beds
of very large boulders and bedrock outcrops, and availability of sediment and large woody debris are believed to be extremely
difficult to restore. Monitoring and evaluation at several scales are needed to test our predictions. 相似文献
17.
Aquaculture activities are embedded in complex social-ecological systems. However, aquaculture development decisions have tended to be driven by revenue generation, failing to account for interactions with the environment and the full value of the benefits derived from services provided by local ecosystems. Trade-offs resulting from changes in ecosystem services provision and associated impacts on livelihoods are also often overlooked. This paper proposes an innovative application of Bayesian belief networks - influence diagrams - as a decision support system for mediating trade-offs arising from the development of shrimp aquaculture in Thailand. Senior experts were consulted (n = 12) and primary farm data on the economics of shrimp farming (n = 20) were collected alongside secondary information on ecosystem services, in order to construct and populate the network. Trade-offs were quantitatively assessed through the generation of a probabilistic impact matrix. This matrix captures nonlinearity and uncertainty and describes the relative performance and impacts of shrimp farming management scenarios on local livelihoods. It also incorporates export revenues and provision and value of ecosystem services such as coastal protection and biodiversity. This research shows that Bayesian belief modeling can support complex decision-making on pathways for sustainable coastal aquaculture development and thus contributes to the debate on the role of aquaculture in social-ecological resilience and economic development. 相似文献
18.
Grigoletto JC Segura-Muñoz SI Barbosa-Junior F Sanches SM Takayanagui AM 《Biological trace element research》2011,144(1-3):316-326
In Brazil, only 20.2% of the municipalities have sewage collection and treatment. The use of medical diagnostic by radiographic processing generates effluents which may contain contaminants such as silver (Ag) that causes irreversible damage to health. They can also contaminate soil, water, and food if there is no treatment before disposal. This study aimed to identify and quantify the Ag concentration in radiographic film-washing water and fixer generated from radiographic processing in 12 Brazilian health institutions, in order to offer subsidies to the environmental and public health managers about this issue. The Ag values found in the washing water films samples ranged from 0.1 to 1,785.97?mg?L(-1). In the fixer samples, the values ranged from 435.59 to 16,325.92?mg?L(-1). These data are far above the values required by Brazilian legislation whose limit is 0.1?mg?L(-1) for Ag in effluents released directly or indirectly into the environment. This research reveals that the disposal of Ag in this kind of effluent needs to be monitored and controlled by the Brazilian government in order to protect both the human and environment health from those contaminants. 相似文献
19.
Marie-Hélène Truchon Lena Measures Vincent L’Hérault Jean-Claude Brêthes Peter S. Galbraith Michel Harvey Sylvie Lessard Michel Starr Nicolas Lecomte 《PloS one》2013,8(3)
Understanding the effects of climatic variability on marine mammals is challenging due to the complexity of ecological interactions. We used general linear models to analyze a 15-year database documenting marine mammal strandings (1994–2008; n = 1,193) and nine environmental parameters known to affect marine mammal survival, from regional (sea ice) to continental scales (North Atlantic Oscillation, NAO). Stranding events were more frequent during summer and fall than other seasons, and have increased since 1994. Poor ice conditions observed during the same period may have affected marine mammals either directly, by modulating the availability of habitat for feeding and breeding activities, or indirectly, through changes in water conditions and marine productivity (krill abundance). For most species (75%, n = 6 species), a low volume of ice was correlated with increasing frequency of stranding events (e.g. R2
adj = 0.59, hooded seal, Cystophora cristata). This likely led to an increase in seal mortality during the breeding period, but also to increase habitat availability for seasonal migratory cetaceans using ice-free areas during winter. We also detected a high frequency of stranding events for mysticete species (minke whale, Balaenoptera acutorostrata) and resident species (beluga, Delphinapterus leucas), correlated with low krill abundance since 1994. Positive NAO indices were positively correlated with high frequencies of stranding events for resident and seasonal migratory cetaceans, as well as rare species (R2
adj = 0.53, 0.81 and 0.34, respectively). This contrasts with seal mass stranding numbers, which were negatively correlated with a positive NAO index. In addition, an unusual multiple species mortality event (n = 114, 62% of total annual mortality) in 2008 was caused by a harmful algal bloom. Our findings provide an empirical baseline in understanding marine mammal survival when faced with climatic variability. This is a promising step in integrating stranding records to monitor the consequences of environmental changes in marine ecosystems over long time scales. 相似文献
20.
The Prospects for Payment for Ecosystem Services (PES) in Vietnam: A Look at Three Payment Schemes 总被引:1,自引:0,他引:1
To PX Dressler WH Mahanty S Pham TT Zingerli C 《Human ecology: an interdisciplinary journal》2012,40(2):237-249
Global conservation discourses and practices increasingly rely on market-based solutions to fulfill the dual objective of
forest conservation and economic development. Although varied, these interventions are premised on the assumption that natural
resources are most effectively managed and preserved while benefiting livelihoods if the market-incentives of a liberalised
economy are correctly in place. By examining three nationally supported payment for ecosystem service (PES) schemes in Vietnam
we show how insecure land tenure, high transaction costs and high opportunity costs can undermine the long-term benefits of
PES programmes for local households and, hence, potentially threaten their livelihood viability. In many cases, the income
from PES programmes does not reach the poor because of political and economic constraints. Local elite capture of PES benefits
through the monopolization of access to forestland and existing state forestry management are identified as key problems.
We argue that as PES schemes create a market for ecosystem services, such markets must be understood not simply as bald economic
exchanges between ‘rational actors’ but rather as exchanges embedded in particular socio-political and historical contexts
to support the sustainable use of forest resources and local livelihoods in Vietnam. 相似文献