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401.
Integrating nature-based tourism and forestry in private lands under heterogeneous visitor preferences for forest attributes 总被引:1,自引:0,他引:1
Erkki Mäntymaa Ville Ovaskainen Artti Juutinen Liisa Tyrväinen 《Journal of Environmental Planning and Management》2018,61(4):724-746
Developing nature-based tourism in private lands calls for new mechanisms to consolidate the interests of the tourism industry, visitors, and landowners. This choice experiment study elaborates on the heterogeneity of visitors’ preferences and willingness to pay (WTP) for enhanced forest amenities and ecosystem services. The survey, targeting domestic and foreign tourists visiting the Ruka-Kuusamo area in Finland, considered four attributes: landscape quality, outdoor routes, forest biodiversity, and carbon sequestration. For observed heterogeneity, the visitors were grouped by their attitudes towards forest management. Unobserved heterogeneity in visitors’ choice behaviour and WTP was examined with the latent class model. While most visitors had environmentally friendly attitudes and were willing to pay, especially for enhanced landscape quality and biodiversity, considerable heterogeneity was revealed in terms of three segments with distinctive attitudes, choice behaviour and WTP. The variation in WTP has important implications for the design of a scheme of payments for environmental management. 相似文献
402.
Status of Species Conservation Banking in the United States 总被引:1,自引:0,他引:1
Abstract: Receiving financial gains for protecting habitat may be necessary to proactively protect endangered species in the United States. Species conservation banking, the creation and trading of "credits" that represent biodiversity values on private land, is nearly a decade old. We detail the biological, financial, and political experience of conservation banking in the United States. We contacted agencies, nongovernmental organizations, and bank owners and compiled comprehensive accounts of the experiences of current banks. There are 76 properties identified as conservation banks in the United States, but only 35 of these are established under a conservation banking agreement approved by the U.S. Fish and Wildlife Service (USFWS). The 35 official conservation banks cumulatively cover 15,987 ha and shelter a range of biodiversity, including more than 22 species listed under the U.S. Endangered Species Act. Financial motives drove the establishment of 91% of conservation banks, and the majority of for-profit banks are breaking even or making money. With credit prices ranging from $3,000 to $125,000/0.41 ha (1 acre), banking agreements offer financial incentives that compete with development and provide a business-based argument for conserving habitat. Although the bureaucracy of establishing an agreement with the USFWS was burdensome, 63% of bank owners reported they would set up another agreement given the appropriate opportunity. Increasing information sharing, decreasing the time to establish agreements (currently averaging 2.18 years), and reducing bureaucratic challenges can further increase the amount of private property voluntarily committed to banking. Although many ecological uncertainties remain, conservation banking offers at least a partial solution to the conservation versus development conflict over biodiversity. 相似文献
403.
Ethan D. Clotfelter 《Behavioral ecology and sociobiology》1997,41(3):193-201
Parental investment by red-winged blackbirds (Agelaius phoeniceus) in response to natural and experi‐mental parasitism by brown-headed cowbirds (Molothrus ater), and in response to freeze-dried, female cowbird mounts presented near redwing nests during the egg-laying period was measured.
Two measures of redwing parental investment were used: nest defense effort toward a model predator, and rate of feeding nestlings.
There were no significant differences in levels of parental investment among unparasitized nests, naturally parasitized nests,
or experimentally parasitized nests. Similarly, parental investment did not differ between redwings that were exposed to the
cowbird mount and those that were not exposed to the mount, or among redwings exposed to the cowbird mount at different distances
from the nest. This suggests that red-winged blackbirds do not recognize when they have been parasitized, and hence do not
associate parasitism with a decrease in their parentage, or that parentage is not an important predictor of parental investment
in this species.
Received: 24 January 1997 / Accepted after revision: 7 June 1997 相似文献
404.
Contrary to vertebrates, sperm production in insects may bear considerable costs for males. This is especially true in species
that donate spermatophores containing sperm and nutrient-rich accessory gland products like in butterflies. Hence, spermatophores
at first and subsequent copulations can differ in a quantitative and qualitative way. Such effects have particularly been
shown in polyandrous species providing large spermatophores. Here we experimentally tested the effect of male mating status
(virgin male vs recently mated male) on copulation duration, spermatophore size and females’ fitness components in a monandrous
butterfly Pararge aegeria that typically donates small spermatophores. Copulations with non-virgin males lasted on average five times longer than that
with virgin males and resulted in a spermatophore which was on average three times smaller. Number of eggs laid and female
life span were not affected by the mating status treatment, but there was a significant effect on the number of living caterpillars
a female produced, as copulations with virgin males resulted in higher numbers of larval offspring. Interestingly, the difference
in spermatophore mass at the first and the second copulation increased with male body size. This suggests differential spermatophore
allocation decisions among males of different size. Consequences for females and potential mechanisms influencing female fitness
components are discussed. Given the small absolute size of spermatophores in P. aegeria, components other than consumable nutrients (perhaps hormones) should cause the observed effects. 相似文献
405.
Diego Gil Alfonso Marzal Florentino de Lope Marisa Puerta Anders P. Møller 《Behavioral ecology and sociobiology》2006,60(1):96-100
Female birds deposit in the yolks of eggs substantial amounts of androgens, such as testosterone and androstenedione. These
androgens have been shown to speed up nestling development, induce a fast development of ornaments and increase dominance
in adults. Experiments in several species have reported that females invest greater amounts of androgens in the eggs fathered
by attractive males, suggesting that yolk androgen is a costly investment for either the offspring or the mother. There is
some evidence that nestling immunocompetence may be partially suppressed by high levels of yolk androgens, but it is not known
whether this is also the case for females. We tested this hypothesis in the house martin by inducing an immune challenge through
an injection of sheep red blood cells, a standard challenge of the humoral immune system. Experimental birds laid eggs with
lower amounts of yolk androstenedione than controls, and there was a similar non-significant trend for testosterone. Furthermore,
the probability of laying a replacement clutch was higher for birds that had laid a first clutch with relatively high levels
of yolk testosterone. These results suggest that yolk androgen deposition is limited by immune costs in the female, and that
only females in good condition may afford to invest high levels of androgen in eggs in this species. 相似文献
406.
Impressive variation in egg colouration among birds has puzzled evolutionary biologists for a long time. The most frequently
studied selective forces moulding egg colouration—predation and brood parasitism—have either received little empirical support
or may play a role in only a minority of species. A novel hypothesis has suggested that egg colour may be significantly influenced
by sexual selection. Females may deposit a blue-green pigment biliverdin into eggshells instead of using it for themselves
as a powerful antioxidant. By this handicap, females may signal their quality to males, which are then hypothesized to increase
their paternal effort. We experimentally tested the hypothesis in the collared flycatcher (Ficedula albicollis), a species laying blue-green eggs. We cross-fostered clutches between nests to disentangle effects of female/territory quality
and egg colour on paternal effort and nestling quality. The results supported two assumptions of sexual signalling through
egg colour hypothesis: Blue pigment seems to be a limited resource for females, and female quality is positively correlated
with the intensity of the blue-green colour. However, we did not find support for the main prediction of the hypothesis, as
male parental effort parameters (feeding frequencies to nestlings and intensity of nest defence) were unrelated to egg colour.
We discuss possible reasons for the discrepancy between our results and previous correlative analyses that supported the hypothesis
that blue egg colour may be a postmating, sexually selected signal in females. 相似文献
407.
Defensive and parental care behaviour of convict cichlids that differed in past effort was compared. Before testing, some fish were bred three times while others were not bred. Age was held constant; all individuals in this study were approximately 20 months old (±2 months) at test time. Furthermore, half of the pairs in this study had their broods experimentally reduced by 50%. Results indicated that past effort across breeding attempts affects investment in the current brood. Experienced pairs were more aggressive toward a model predator than inexperienced parents. However, no major differences were observed in depreciable care (i.e. fanning). Contrary to previous studies, brood size had minor effects on parental care. This discrepancy could be due to the age of the parents; individuals in this study were significantly older than fish tested in previous studies. The results support parental investment theory and suggest that past effort is not only important within breeding episodes but also within an animal's lifetime. 相似文献
408.
从安全工程学、安全经济学、人机工程学入手,结合金川公司安全生产工作的实际,对现代企业安全管理中的十个关系进行了探讨。 相似文献
409.
In many countries, a large proportion of forest biodiversity exists on private land. Legal restrictions are often inadequate to prevent loss of habitat and encourage forest owners to manage areas for biodiversity, especially when these management actions require time, money, and other resources. Environmental programs encouraging these actions through economic incentives can be used instead of additional legal restrictions, although to be efficient and successful, an incentive program must be thoughtfully developed and its conservation goals must be clear. In addition to being economically efficient, programs must be acceptable to landowners and ecologically appropriate, especially with respect to the case-specific objectives and the ecosystems in question. We introduce a sample of voluntary incentive programs for private forests in Europe and North America. We briefly describe the economic, social, and ecological characteristics of the programs and the forests they aim to conserve, and evaluate the success of these programs with respect to their explicitly stated goals and the ecological status of the forests in that country or state. Important factors contributing to program success include an allowance for some economic productivity in enrolled forests, a long period since time of program inception, and little interference from other incentive programs. 相似文献
410.
环境保护投资的市场化运作 总被引:2,自引:0,他引:2
环境保护投资是解决环境问题的重要保障。分析了我国环境保护投资存在的主要问题及其原因,对我国环境保护投资的市场化运作进行分析,提出了社会主义市场经济体制下筹集环境保护投资、环境保护管理及环境保护设施管理的主要措施。 相似文献