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61.
This paper reexamines the backward incidence of pollution control using duality theory for a two-sector general equilibrium model in which the economy experiences large-scale unemployment and perfect capital mobility with a sector-specific rigid wage in the polluting sector. In this context it is shown that with stricter pollution controls the wage rate in the nonpolluting sector rises while the common rental rate falls. In addition, stricter pollution controls are shown to have an uncertain impact on national income. 相似文献
62.
The aim of this paper is to use Erikson's approach to human development, and specifically generativity, as a framework by which to explore older people's experiences of environmental stewardship activities. Using data from a large qualitative study of environmental volunteers resident in the coastal fringes of Queensland, Australia, the paper provides important, illustrative, empirical support for Erikson's theory of generativity in later life. Findings suggest that older people are much more likely to connect their environmental actions with the longer-term future, and express a need to leave a lasting legacy for future generations. According to respondents, the later years are a time to contribute to the environment as part of a broader cycle of life. The environment is also an important site for intergenerational activities. Whilst the work presented here is only a small, localized study, use of Erikson's theory of human development as a framework helps demonstrate the importance of a generative response in later life. 相似文献
63.
Summary Since the late 1970s, the National Environment Secretariat (NES) in Kenya has viewed environmental impact assessment (EIA) as a principal tool for meeting its environmental protection objectives. Prior to the formation of the Inter-Ministerial Committee on the Environment (IMCE), NES was ineffective in forcing any project proponents to take the EIA requirements seriously. The IMCE has provided NES with the ability to co-opt Committee members and to use the legislatively based mandates of those members to enforce its EIA requirements for industrial projects. A successful example of this co-optation is the case of the Leather Industries of Kenya (LIK), involving a new tannery whose final siting and wastewater treatment control facilities were substantially influenced by the EIA process. Although the LIK case does not offer a basis for generalisation, it provides insights into: (a) how EIA is implemented for new industrial facilities in Kenya, (b) the advantages and disadvantages of the EIA system, and (c) the constructive roles donor agencies can play in promoting institutional reforms for EIA.Dr Rafik Hirji is a Senior Engineer at James M. Montgomery Consulting Engineers, Inc., Suite 160, Sacramento, CA 95825. He was formerly a graduate research assistant in the Department of Civil Engineering at Stanford University. Dr Leonard Ortolano is the UPS Foundation Professor of Civil Engineering at Stanford University, Stanford, CA 94305-4020, USA. 相似文献
64.
Mark J. Pettenati Margaret Berry Vandana Shashi J. Hartley Bowen Margaret Harper 《黑龙江环境通报》2001,21(6):435-440
The prenatal diagnosis of a complete trisomy of the long arm of chromosome 1 is reported. Major ultrasound findings included: nuchal thickening, bi-temporal narrowing, a single choroid plexus cyst, andmild ventriculomegaly. There was a mass in the chest and abdomen, pleural effusion, ascites and a hyperechoic bowel. Skin edema was present. The fetus died at 26 weeks' gestation. A literature review is presented of 17 de novo and two inherited cases with only trisomy 1q. Of note is the fact that 3/5 prenatally detected 1q trisomies have teratomas. A review of the literature reveals a dismal outcome fortrisomy 1q cases if the duplication involves bands 1q25→q32. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
65.
Although palms are the most commonly harvested tree family in the world, they are susceptible to overexploitation, and many harvest schemes are not sustainable. We assessed the impact of leaf harvesting of the Asian palm, Livistona rotundifolia , in North Sulawesi, Indonesia, to determine the effect of harvest intensity on subsequent growth and to determine if current harvest practices are ecologically sustainable. We conducted experimental harvests of two intensities and compared results with a control. Leaf emergence, expansion, opening, and maturation were monitored for 1 year. Leaves in heavy and light harvest treatments grew and opened significantly faster than control leaves. Final leaf size was a function of harvest intensity: control leaves were larger (4.06 m) than light-harvest leaves (3.62 m) and heavy-harvest leaves (2.62 m). Census results for palms in harvested and unharvested areas indicated that palm density was twice as high and reproductive-sized palms were 10 times more common in the unharvested area. We judged current harvest practices to be nonsustainable. Recommendations for sustainable harvesting include reduction of harvest intensity and waste and preservation of reproductive-sized palms. 相似文献
66.
Margaret Gooch 《Local Environment》2005,10(1):5-19
This paper discusses findings of a study of catchment care volunteers drawn from the east coast of Queensland, Australia. Catchment volunteering includes individuals in not-for profit stewardship groups with a catchment focus. Catchment volunteering was experienced by participants as maintaining a balance of perspectives; developing/maintaining an identity; networking; learning; empowering; and sustainable. An illustrative model (the Outcome Space), representing a set of scales, shows the relationship between conceptions.
Results indicate that catchment volunteering offers many benefits to individuals and local communities. Although there were frustrations at times, many volunteers expressed deep levels of satisfaction about their volunteering experiences. Results suggest that satisfied volunteers are those that manage to balance volunteering with other aspects of their lives; identify strongly with some aspect of volunteering; enjoy learning from their volunteer experiences; and were willing and able to share and apply their new knowledge in a variety of ways. They also made friends with other volunteers; felt valued by others in the group, and believed that what they do is important. For these respondents, volunteering contributes richly to the fabric of their lives, providing meaning and satisfaction in routine activities, enhancing local communities and building sustainability. 相似文献
Results indicate that catchment volunteering offers many benefits to individuals and local communities. Although there were frustrations at times, many volunteers expressed deep levels of satisfaction about their volunteering experiences. Results suggest that satisfied volunteers are those that manage to balance volunteering with other aspects of their lives; identify strongly with some aspect of volunteering; enjoy learning from their volunteer experiences; and were willing and able to share and apply their new knowledge in a variety of ways. They also made friends with other volunteers; felt valued by others in the group, and believed that what they do is important. For these respondents, volunteering contributes richly to the fabric of their lives, providing meaning and satisfaction in routine activities, enhancing local communities and building sustainability. 相似文献
67.
Summary Larvae of Myrmeleon immaculatus in large pits captured both large and samll prey, while larvae in small pits captured only the small prey. Larvae in small pits did not respond to large ants, although they always responded by sand-flinging to small ants. Larvae in medium-sized pits often captured large ants only after prolonged and vigorous sand-flipping. Larvae in large pits usually captured large ants with relatively little sand-flipping. Pit enlargement and pit relocation in the laboratory were not significantly correlated with reduction of rations in the first 3 weeks after a pit was built. However, after a month without food, larvae on the average moved once every 10 days, built successively smaller pits, and moved longer distances before building a new pit. In the field pits were dug primarily in response to microclimatological factors and possibly edge-effects. The presence or absence of suitable prey at a site, per se, had no effect on whether or not a larva would dig a pit there. We conclude that these sit-and-wait predators have a relatively large repertoire of behavior that enhances their foraging success, and we contrast it with previously made optimal foraging models relating to pit locations, pit relocations, pit size and ant lion responses. 相似文献
68.
69.
Margaret E. Elmes MB BS PhD J. Clarkson PhD J. Gwyn Jones PhD 《Environmental geochemistry and health》1983,5(2-3):85-87
The zinc content of intestinal epithelial cells in human jejunum and ileum has been measured using X-ray microanalysis. The range of values was wide, the highest being found in stem cells and enterocytes. Significant differences were found in jejunum from gastric carcinoma patients and ileum from Crohn's disease patients compared with patients with non malignant, non inflammatory disease. 相似文献
70.
Nina Rønsted Seana K. Walsh Margaret Clark Merlin Edmonds Tim Flynn Scott Heintzman Alexander Loomis David Lorence Uma Nagendra Ben Nyberg Michael Opgenorth Lauren Weisenberger Adam Williams Dustin Wolkis Kenneth R. Wood Matthew Keir 《Conservation biology》2022,36(4):e13896
The International Union for Conservation of Nature's Red List of Threatened Species (IUCN Red List) is the world's most comprehensive information source on the global conservation status of species. Governmental agencies and conservation organizations increasingly rely on IUCN Red List assessments to develop conservation policies and priorities. Funding agencies use the assessments as evaluation criteria, and researchers use meta-analysis of red-list data to address fundamental and applied conservation science questions. However, the circa 143,000 IUCN assessments represent a fraction of the world's biodiversity and are biased in regional and organismal coverage. These biases may affect conservation priorities, funding, and uses of these data to understand global patterns. Isolated oceanic islands are characterized by high endemicity, but the unique biodiversity of many islands is experiencing high extinction rates. The archipelago of Hawaii has one of the highest levels of endemism of any floristic region; 90% of its 1367 native vascular plant taxa are classified as endemic. We used the IUCN's assessment of the complete single-island endemic (SIE) vascular plant flora of Kauai, Hawaii, to assess the proportion and drivers of decline of threatened plants in an oceanic island setting. We compared the IUCN assessments with federal, state, and other local assessments of Kauai species or taxa of conservation concern. Finally, we conducted a preliminary assessment for all 1044 native vascular plants of Hawaii based on IUCN criterion B by estimating area of occupancy, extent of occurrence, and number of locations to determine whether the pattern found for the SIE vascular flora of Kauai is comparable to the native vascular flora of the Hawaiian Islands. We compared our results with patterns observed for assessments of other floras. According to IUCN, 256 SIE vascular plant taxa are threatened with extinction and 5% are already extinct. This is the highest extinction risk reported for any flora to date. The preliminary assessment of the native vascular flora of Hawaii showed that 72% (753 taxa) is threatened. The flora of Hawaii may be one of the world's most threatened; thus, increased and novel conservation measures in the state and on other remote oceanic islands are urgently needed. 相似文献