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1.
Maolin Li Xianshi Jin Qisheng Tang 《Journal of Agricultural and Environmental Ethics》2012,25(1):33-54
Marine ecosystems are in serious troubles globally, largely due to the failures of fishery resources management. To restore
and conserve fishery ecosystems, we need new and effective governance systems urgently. This research focuses on fisheries
management in ancient China. We found that from 5,000 years ago till early modern era, Chinese ancestors had been constantly
enthusiastic about sustainable utilization of fisheries resources and natural balance of fishery development. They developed
numerous rigorous policies and regulations to guide people to act on natural laws. Being detailed and scientific, the legal
systems had gained gratifying enforcement, due to official efforts and folks’ voluntary participation in resource management.
In-depth analyses show that people’s consciousness of ecological conservation was derived from the edification of kinds of
ancient eco-ethical wisdom, such as totemism, nature worship, Zhou Yi, Taoism, Buddhism, Confucianism, Mohism, etc. All this Chinese classical wisdom have the same cores: “Nature and Man in One”
spirit, frugality and “All things are equal” concept. The findings show that eco-ethical thinking is never inconsistent with
social ethic systems, and it’s of great importance to give legal effect to usual ecological moral claims and eco-ethical requirements
of the public in protecting the environment. The eco-ethical wisdom is efficient in assisting and urging people to fulfill
humans’ obligation for nature. Finally, it’s believed that present world fisheries management will benefit a lot from all
these ancient Chinese thoughts and practices. People are expected to make the most of the eco-ethical wisdom, strengthen fishery
legislation and fully stimulate their voluntary participation in both marine fishery resources conservation and fishery cyclic
economy. 相似文献
2.
Sekhar NU 《Environmental management》2007,39(4):497-505
This article shows how social capital impacts fisheries management at the local level in Chilika Lake, located in the state
of Orissa in India. In Chilika, the different fishing groups established norms and “rules of the game” including, but not
limited to, spatial limits that determine who can fish and in what areas, temporal restrictions about when and for how long people may fish, gear constraints about what harvesting gear may be used by each group, and physical controls on size and other characteristics of fish that may be harvested. A survey of the members of fishing groups has shown
that the bonding social capital is strong within the Chilika fishing groups. Bonding and bridging social capital keeps the
fishers together in times of resource scarcity, checks violations of community rules and sanctions, and strengthens the community
fisheries management. In contrast, linking social capital in Chilika appears to be weak, as is evident from the lack of trust
in external agencies, seeking the help of formal institutions for legal support, and increasing conflicts. Trust and cooperation
among fishers is crucial in helping to build the social capital. A social capital perspective on fisheries governance suggests
that there should be a rethinking of priorities and funding mechanisms, from “top-down” fisheries management towards “co-management”
with a focus on engendering rights and responsibilities for fishers and their communities. 相似文献
3.
Frank Merry Britaldo Soares-Filho Daniel Nepstad Gregory Amacher Hermann Rodrigues 《Environmental management》2009,44(3):395-407
Logging has been a much maligned feature of frontier development in the Amazon. Most discussions ignore the fact that logging
can be part of a renewable, environmentally benign, and broadly equitable economic activity in these remote places. We estimate
there to be some 4.5 ± 1.35 billion m3 of commercial timber volume in the Brazilian Amazon today, of which 1.2 billion m3 is currently profitable to harvest, with a total potential stumpage value of $15.4 billion. A successful forest sector in
the Brazilian Amazon will integrate timber harvesting on private lands and on unprotected and unsettled government lands with
timber concessions on public lands. If a legal, productive, timber industry can be established outside of protected areas,
it will deliver environmental benefits in synergy with those provided by the region’s network of protected areas, the latter
of which we estimate to have an opportunity cost from lost timber revenues of $2.3 billion over 30 years. Indeed, on all land
accessible to harvesting, the timber industry could produce an average of more than 16 million m3 per year over a 30-year harvest cycle—entirely outside of current protected areas—providing $4.8 billion in returns to landowners
and generating $1.8 billion in sawnwood sales tax revenue. This level of harvest could be profitably complemented with an
additional 10% from logging concessions on National Forests. This advance, however, should be realized only through widespread
adoption of reduced impact logging techniques. 相似文献
4.
Assessment of Coastal Vulnerability Through the Use of GIS Tools in South Sicily (Italy) 总被引:1,自引:0,他引:1
This study assessed coastal erosion vulnerability along a 90-km sector, which included both erosional and accretionary beaches,
and different levels of human occupation. Two aerial photogrammetric flights were used to reconstruct coastal evolution between
1977 and 1999. During this period, extensive accretion was recorded updrift of human structures at harbors and ports, e.g.,
Scoglitti (105.6 m), Donnalucata (52.8 m), and Pozzallo (94.6 m). Conversely, erosion was recorded in downdrift areas, with
maximum values at Modica Stream mouth (63.8 m) and Point Castellazzo (35.2 m). Assessments were subsequently divided into
four categories ranging from “high erosion” to “accretion.” Several sources were examined to assess human activities and land
use. The latter was mapped and divided into four categories, ranging from “very high” to “no capital” land use. Subsequently,
coastal erosion vulnerability was assessed by combining land use categories with recorded coastline behavior. Results showed
“very high” to “high” vulnerability along 5.8% and 16.6%, respectively, of the littoral, while 20.9% and 56.7%, respectively,
was found to exhibit “medium” and “low/very low” vulnerability. A very good agreement between predicted coastal vulnerability
and coastal trend had been observed over recent years. Furthermore, several human structures and activities are located within
the “imminent collapse zone (ICZ)” which reached maximum values of 17.5 m at Modica Stream and 13.5 m at Point Braccetto. 相似文献
5.
This article develops a dynamic model of efficient use of exhaustible marine sand resources in the context of marine mining externalities. The classical Hotelling extraction model is applied to sand mining in Ongjin, Korea and extended to include the estimated marginal external costs that mining imposes on marine fisheries. The socially efficient sand extraction plan is compared with the extraction paths suggested by scientific research. If marginal environmental costs are correctly estimated, the developed efficient extraction plan considering the resource rent may increase the social welfare and reduce the conflicts among the marine sand resource users. The empirical results are interpreted with an emphasis on guidelines for coastal resource management policy. 相似文献
6.
Andrés M. Cisneros‐Montemayor F. Gordon Kirkwood Sarah Harper Dirk Zeller U. Rashid Sumaila 《Natural resources forum》2013,37(4):221-230
The announcement of plans for exploratory oil drilling at a number of offshore sites in Belize raised concerns about the risks associated with drilling, particularly given the socio‐economic importance of the marine ecosystem. The current economic value of fisheries and marine ecotourism is estimated, along with the potential revenue from offshore oil and potential economic losses stemming from oil pollution, under various assumptions on risk and uncertainty. Marine fisheries and ecotourism are estimated to generate around US$ 183 million per year. Single‐year estimated maximum revenue is higher for oil extraction initially but quickly declines; during a 50 year (two generation) period, total discounted benefits from marine fisheries and ecotourism are estimated at US$ 5.1 billion, compared to US$ 3.2 billion from offshore oil revenue. Following a hypothetical oil spill, discounted losses in marine fisheries and ecotourism due to perception and ecological impacts are estimated at US$ 912 million, with clean‐up costs and capital losses of US$ 6.1‐10.4 billion. Considering the short extraction life of oil resources compared to fisheries and ecotourism, the difference in benefits increases substantially in favour of the latter with a longer time horizon. A recent public referendum resulted in a 98% vote against oil exploration and a subsequent annulment of oil concessions pending environmental impact assessments. 相似文献
7.
Mekong River Fish Conservation Zones in Southern Laos: Assessing Effectiveness Using Local Ecological Knowledge 总被引:2,自引:0,他引:2
Small-scale fisheries are important in Laos, where rural people heavily depend upon Mekong River and tributary fish stocks
for their livelihoods. Increasing pressures from human exploitation and habitat disturbance, however, have raised serious
concerns about the potential depletion of various species. This has led to the establishment of large numbers of Fish Conservation
Zones (FCZs) or “no-take” fish sanctuaries in southern Laos based on a “community-based fisheries co-management” framework.
This study uses the local ecological knowledge (LEK) of fishers to assess the effectiveness of village-managed FCZs in enhancing
fish stocks in the mainstream Mekong River in Khong District, Champasak Province. Focus group interviews about species that
are believed to have benefited from different FCZs are compared with parameters such as FCZ area, age, depth, localized gradient,
water velocity, and the presence of wetland forests nearby. The results suggest that no one aspect is likely to account for
variations in fish stocks; rather, it is the interaction between numerous factors that has the largest impact. Secondly, the
results indicate that microhabitat diversity and protection are critical for maintaining and enhancing Mekong fisheries. Deep-water
pools are particularly important as dry season refuges for many fish species, and FCZ depth may be the single most important
environmental factor affecting the success of FCZs in the Mekong River. FCZs have the most potential to benefit relatively
sedentary species, but may also benefit highly migratory species, given the right conditions. This study shows that integrated
approaches to stock assessment that employ LEK and scientific fisheries management have considerable potential for improving
Mekong capture-fisheries management. 相似文献
8.
Ruchi Badola Syed Ainul Hussain Bidyut Kumar Mishra Bidyarani Konthoujam Sneha Thapliyal Parag Madhukar Dhakate 《The Environmentalist》2010,30(4):320-329
This paper examines the economic value of selected ecosystem services of Corbett Tiger Reserve, India. The direct cost was
derived from secondary sources, and indirect and opportunity costs through socioeconomic surveys. For recreational value the
individual approach to travel cost method was used, and to assess carbon sequestration the replacement cost method was used.
The maintenance cost of the reserve was estimated as US $2,153,174.3 year−1. The indirect costs in terms of crop and livestock depredation by wild animals ranged from US $2,153,174.3 year−1. The indirect costs in terms of crop and livestock depredation by wild animals ranged from US 2,408 to US $37,958 village−1 over a period of 5 years. The dependence of local communities was for fuel wood (US $37,958 village−1 over a period of 5 years. The dependence of local communities was for fuel wood (US 7,346 day−1), fodder (US $5,290 day−1), small timber, and other nontimber forest products. The recreational value of the reserve was estimated as US $5,290 day−1), small timber, and other nontimber forest products. The recreational value of the reserve was estimated as US 167,619 year−1. With the cost per visitor being US $2.5, the consumers’ surplus was large, showing the willingness of visitors to pay for
wildlife recreation. The forests of the reserve mitigate carbon worth US $2.5, the consumers’ surplus was large, showing the willingness of visitors to pay for
wildlife recreation. The forests of the reserve mitigate carbon worth US 63.6 million, with an annual flow of US $65.0 ha−1 year−1. The other benefits of the reserve include US $65.0 ha−1 year−1. The other benefits of the reserve include US 41 million through generation of electricity since 1972. The analysis reveals
that, though the benefits outweigh costs, they need to be accrued to local communities so as to balance the distribution of
benefits and costs. 相似文献
9.
Kepe T 《Environmental management》2008,41(3):311-321
Comanagement has recently become the most popular approach for reconciling land claims and biodiversity conservation in South
Africa and beyond. Following the resolution of land claims on protected areas in South Africa, comanagement arrangements have
been created between the relevant conservation authorities and the land claimant communities who are legally awarded tenure
rights to the land. However, it is doubtful that these partnerships constitute success for the former land claimants. Using
the case of a “resolved” land claim in Mkambati Nature Reserve, Eastern Cape Province, as well as insights from comanagement
literature, this paper identifies and discusses three key possible reasons for the unimpressive performance of comanagement
in reconciling land restitution and conservation. The first one is the origins of the comanagement idea in the conservation
of high value natural resources (e.g., fisheries, forestry), rather than in or including concerns for resource rights. The
second reason is the neglect of key conditions for successful comanagement, as discussed in the comanagement literature. The
final reason is the ambiguity in settlement agreements, including the use of terminology and concepts that reinforce unequal
power relationships, with the state emerging as the powerful partner. This paper concludes that, unless there is a serious
reassessment of the comanagement idea as a way of reconciling land reform and conservation, and a possible review of settlement
agreements that have relied on comanagement, both the integrity of the “successful land claimant’s rights” and that of conservation
remain under threat. 相似文献
10.
Prakash Basnyat Lawrence Teeter B. Graeme Lockaby Kathryn M. Flynn 《Environmental management》2000,26(2):153-161
In this study, water quality and basin characteristics data from different basins of the Fish River basin, Baldwin County,
Alabama, were used to develop a valuation model. This valuation model is based on the effectiveness of “contributing zones”
identified and delineated using methods described by Basnyat and others (Environmental Management]1999] 23(4):539–549). The “contributing zone” delineation model suggests that depending on soil permeability, soil moisture,
depth to water table, slope, and vegetation, buffer widths varying from 16 m to 104 m must be maintained to assimilate or
detain more than 90% of the nitrate passing through the buffers. The economic model suggests the value of retiring lands (to
create the buffers) varies from $0 to $3067 per ha, depending on the types of crops currently grown. The total value of retiring
all areas identified by the contributing zone model is $1,125,639 for the study area. This land value will then form the basis
for estimates of the costs of land management options for improving (or maintaining) water quality throughout the study area. 相似文献
11.
The study deals with the problem of evaluating management strategies for pure stands of Norway spruce (Picea abies Karst) to balance adaptation to and mitigation of climate change, taking into account multiple objectives of a forest owner.
A simulation and optimization approach was used to evaluate the management of a 1000 ha model Age-Class forest, representing
the age-class distribution of an area of 66,000 ha of pure Norway spruce forests in the Black Forest region of Southwest Germany.
Eight silvicultural scenarios comprising five forest conversion schemes which were interpreted as “adaptation” strategies
which aims at increasing the proportion of Beech, that is expected to better cope with climate change than the existing Norway
spruce, and three conventional strategies including a “Do-nothing” alternative classified as “mitigation”, trying to keep
rather higher levels of growing stock of spruce, were simulated using the empirical growth simulator BWINPro-S. A linear programming
approach was adapted to simultaneously maximize the net present values of carbon sequestration and timber production subject
to the two constraints of wood even flow and partial protection of the oldest (nature protection). The optimized plan, with
the global utility of 11,687 €/ha in forty years, allocated a combination of silvicultural scenarios to the entire forest
area. Overall, strategies classified as “mitigation” were favored, while strategies falling into the “adaptation”-category
were limited to the youngest age-classes in the optimal solution. Carbon sequestration of the “Do-nothing” alternative was
between 1.72 and 1.85 million tons higher than the other alternatives for the entire forest area while the differences between
the adaptation and mitigation approaches were approximately 133,000 tons. Sensitivity analysis showed that a carbon price
of 21 €/t is the threshold at which carbon sequestration is promoted, while an interest rate of above 2% would decrease the amount
of carbon. 相似文献
12.
Hill MJ Lesslie R Donohue R Houlder P Holloway J Smith J Ritman K 《Environmental management》2006,37(5):712-731
The purpose of this study was to help to inform policy development for the Australian rangelands, and provide a proof of concept
for application of a multi-criteria analysis approach to assessment of competing resource use at continental scale. The study
aimed to identify and locate key natural resource and agricultural production assets in the rangelands, define a number of
measures of potentially threatening processes, and use a multi-criteria approach to identify areas where threatening processes,
agricultural production problems, or valuable natural resources coincided. The analysis used 35 readily available, continental
spatial data layers at 5-km pixel resolution ranked from 1 (low) to 5 (high) under three themed groupings: natural resource
base, production base, and threatening processes. These measures were aggregated into composite indicators to define attributes
such as environmental sensitivity and total grazing pressure. The composites were then compared in a two-way analysis to explore
particular interactions between threatening processes such as pastoralism and mining, and the condition of production and
natural resource assets. These interactions were defined as “tensions” for purposes of this analysis. Example “tensions” included
the association of high grazing intensity with areas of high environmental sensitivity, indicating a risk of land degradation
under adverse climatic conditions. A summary of patterns of tension was obtained by extracting area proportions of high-tension
classes for selected Natural Heritage Trust Regions, which are a basis for Australian Government funding of improved environmental
management. The study provides a basis for further examination of trade-offs in the use of natural assets, opportunities for
improved productivity and sustainability, and social and economic implications. 相似文献
13.
The history of the establishment and management philosophies of the mainland Portuguese Protected Areas was reconstructed
through the use of written records and oral history interviews. The objectives were to review the main philosophies in the
creation and management of these areas, to assess the influence of international PA models, to compare the Portuguese case
with other European and international literature concerning PAs and to discuss the value of the oral history in this research.
As main results, it was found that the initial management model of “Wilderness (or Yellowstone)” was replaced by the “new
paradigm” of PAs when the democracy was re-established. Changes in the management philosophies within this “new paradigm”
were also identified, which resulted in the transition of a “Landscape” to a “Nature conservation” model. After the establishment
of the Natura 2000 network, the “Biodiversity conservation” model prevailed. It was also found that the initiative for the
establishment of most PAs came from the government, although there were few cases of creation due to the action of NGOs and
municipalities. Finally, oral history interviews enabled the addition of information to the literature review, but also provided
more insight and detail to this history. 相似文献
14.
Green Space Changes and Planning in the Capital Region of China 总被引:4,自引:0,他引:4
Green space plays an important role in complex urban ecosystems and provides significant ecosystem services with environmental,
aesthetic, recreational and economic benefits. Beijing is the capital city of China and has a large population of about 15.81
million. Construction of green spaces is an important part of sustainable development in Beijing. To attain the sustainable
development of Beijing as a capital city, an international city, a historical cultural city, and a living amenity city, this
article attempts to develop a comprehensive plan of green space development both at the municipal and regional levels. At
the municipal level of Beijing, based on the study of green space changes, and taking physical geographic conditions and historical
context into account, we propose to establish green barriers in the mountainous area, and plan a comprehensive green space
pattern composed of one city, two rings, three networks, eight water areas, nine fields, and several patches in the plain
area. At the regional level of the Capital Circle Region, integrating the characteristics and causes of main environmental
issues, we design a macroscopic pattern—“barriers by mountains in the northwest,” “seaward open spaces in the southeast,”
“grassland-forest-field-coast zones,” and “green-blue symphony”—for ecological restoration and green space construction. Finally,
we discuss the principles necessary to implement green space planning considering adaptation to local conditions, composite
function exploitation, interregional equity and integrated planning. 相似文献
15.
Dunja Jaber 《Journal of Agricultural and Environmental Ethics》2000,13(1-2):29-42
In their report for the Swiss government on the notion of the dignity of creatures, Philipp Balzer, Klaus-Peter Rippe, and
Peter Schaber analyze the relationship between human dignity and the dignity of creatures, taking them as two categorically
different concepts. Human dignity is defined as the “moral right not to be humiliated,” whereas the dignity of creatures is
taken to be “the inherent value of non-human living beings.” To my mind there is no need to draw a categorical distinction
between the two concepts. Both notions could be brought together under an all-encompassing concept of the inherent value of
living beings, humans and non-humans alike, a concept one could name “the dignity of living beings.” Indeed, this very notion
underlies the position taken in the report, although this is not made explicit by the authors themselves.
As the aim of the paper is only to clarify the concepts used, I do not go beyond this “internal” critique of their position,
i.e., I don’t assess how the claims articulated via these concepts — the claim that humans and/or creatures have an inherent
value consisting in a supposed intrinsic good — are to be justified, although I myself would be rather skeptical that this
might be successfully done. 相似文献
16.
Brad D. Wolaver Cassandra E. Cook David L. Sunding Stephen F. Hamilton Bridget R. Scanlon Michael H. Young Xianli Xu Robert C. Reedy 《Journal of the American Water Resources Association》2014,50(5):1081-1101
Texas water resources, already taxed by drought and population growth, could be further stressed by possible listings of endangered aquatic species. This study estimated potential economic impacts of environmental flows (EFs) for five freshwater unionid mussels in three Central Texas basins (Brazos, Colorado, and Guadalupe‐San Antonio Rivers) that encompass 36% of Texas (~246,000 km2). A water availability model projected reductions in water supply to power, commercial and industrial, municipal, and agriculture sectors in response to possible EFs for mussels. Single‐year economic impacts were calculated using publicly available data with and without water transfers. Benefits of EFs should also be assessed, should critical habitat be proposed. Potential economic losses were highest during droughts, but were nominal (<$1 M) in wetter years — even with high EFs. Reduced supplies to San Antonio area power plants caused worst‐case impacts of a single‐year shutdown up to $107 million (M) during drought with high EFs. For other sectors in the study area, water transfers reduced worst‐case losses from $80 to $11 M per year. Implementing innovative water management strategies such as water markets, conjunctive use of surface water and groundwater, aquifer storage and recovery could mitigate economic impacts if mussels — or other widely distributed aquatic species — were listed. However, approaches for defining EFs and strategies for mitigating economic impacts of EFs are needed. 相似文献
17.
18.
Strange E Galbraith H Bickel S Mills D Beltman D Lipton J 《Environmental management》2002,29(2):290-300
The amount of ecological restoration required to mitigate or compensate for environmental injury or habitat loss is often
based on the goal of achieving ecological equivalence. However, few tools are available for estimating the extent of restoration
required to achieve habitat services equivalent to those that were lost. This paper describes habitat equivalency analysis
(HEA), a habitat-based “service-to-service” approach for determining the amount of restoration needed to compensate for natural
resource losses, and examines issues in its application in the case of salt marsh restoration. The scientific literature indicates
that although structural attributes such as vegetation may recover within a few years, there is often a significant lag in
the development of ecological processes such as nutrient cycling that are necessary for a fully functioning salt marsh. Moreover,
natural variation can make recovery trajectories difficult to define and predict for many habitat services. HEA is an excellent
tool for scaling restoration actions because it reflects this ecological variability and complexity. At the same time, practitioners
must recognize that conclusions about the amount of restoration needed to provide ecological services equivalent to those
that are lost will depend critically on the ecological data and assumptions that are used in the HEA calculation. 相似文献
19.
A contingent valuation study was conducted with adult Kenyan citizens and foreign tourists to estimate the value of recreational
benefits arising from coral reefs at Mombasa Marine National Park and Reserve (MMNPR), and to assess the implications for
local reef management. Citizen and foreign visitors to MMNPR were willing to pay an extra $2.2 (median = $2.2 (median = 1.6) and $8 (median = $8 (median = 6.7)
per visit respectively, in addition to current park entrance fees, to support reef quality improvements. By aggregating visitors’
willingness to pay bids over the number of visitors to MMNPR in 2006–2007 the value of benefits was estimated at 346,733, which was more than twice the total annual operational expenditure of346,733,
which was more than twice the total annual operational expenditure of 152,383 for MMNPR. The findings indicate that annual
revenues from citizen and foreign visitors may be increased by 60% to 261,932 through the implementation of proposed higher park fees of261,932 through the implementation of proposed higher
park fees of 3.10 for citizens and $15 for foreign visitors. However, any fee increase would serve to intensify concerns
among citizens that only relatively affluent Kenyans can afford to visit MMNPR. Park managers need to demonstrate that the
extra revenue would be used to fund the proposed conservation activities. This valuation study demonstrates that visitors
are prepared to pay higher user fees for access to the marine protected area revealing considerable untapped resource to finance
reef quality improvements. 相似文献
20.
The Concept of Farm Animal Welfare: Citizen Perceptions and Stakeholder Opinion in Flanders, Belgium
Filiep Vanhonacker Wim Verbeke Els Van Poucke Zuzanna Pieniak Griet Nijs Frank Tuyttens 《Journal of Agricultural and Environmental Ethics》2012,25(1):79-101
Several attempts to conceptualize farm animal welfare have been criticized for diverging reasons, among them often the failure
to incorporate the public concern and opinion. This paper’s objective is to develop a conception of farm animal welfare that
starts from the public’s perception and integrates the opinion of different stakeholder representatives, thus following a
fork-to-farm approach. Four qualitative citizen focus group discussions were used to develop a quantitative questionnaire,
which has been completed by a representative sample of Flemish citizens (n = 459). Exploratory and confirmatory factor analyses were applied to develop a conception of farm animal welfare starting
from an extended list of aspects that relate to animal production and associate with farm animal welfare in the public’s perception.
In depth interviews with stakeholder representatives were used to match and adapt the structure of the animal welfare conception
model. The resulting conception revealed seven dimensions grouped in two different levels. Three dimensions were animal-based:
“Suffering and Stress,” “Ability to Engage in Natural Behavior,” and “Animal Health.” Four dimensions were resource-based:
“Housing and Barn climate,” “Transport and Slaughter,” “Feed and Water,” and “Human-Animal Relationship.” This conception
is distinct from earlier attempts since it is based on public perceptions; it addresses the opinion of different stakeholders,
and it distinguishes empirically between animal-based and resource-based dimensions in the conceptualization of farm animal
welfare. The relevancy of a popular definition is supported by the present demand oriented economy, in which animal welfare
is a non-trade concern, and mainly left to the market where consumers still mainly act as individuals who calculate and weigh
pros and cons. 相似文献