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Koala Conservation Policy Process: Appraisal and Recommendations 总被引:1,自引:0,他引:1
Tim W. Clark Nicole Mazur † Steven J. Cork ‡ Steve Dovers § and Ronnie Harding 《Conservation biology》2000,14(3):681-690
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Daniel J. Bain Erin M. Copeland Marion T. Divers Marijke Hecht Kristina G. Hopkins Justin Hynicka Michael Koryak Mary Kostalos Lisa Brown Emily M. Elliott Joseph Fedor Michele Gregorich Brady Porter Brenda Smith Christopher Tracey Margaret Zak 《Journal of the American Water Resources Association》2014,50(6):1608-1621
Urban stream restoration continues to be used as an ecological management tool, despite uncertainty about the long‐term sustainability and resilience of restored systems. Evaluations of restoration success often focus on specific instream indicators, with limited attention to the wider basin or parallel hydrologic and geomorphic process. A comprehensive understanding of urban stream restoration progress is particularly important for comparisons with nonurban sites as urban streams can provide substantial secondary benefits to urban residents. Here, we utilize a wide range of indicators to retrospectively examine the restoration of Nine Mile Run, a multi‐million dollar stream restoration project in eastern Pittsburgh (Pennsylvania, USA). Examination of available continuous hydrological data illustrates the high cost of failures to incorporate the data into planning and adaptive management. For example, persistent extreme flows drive geomorphic degradation threatening to reverse hydrologic connections created by the restoration and impact the improved instream biotic communities. In addition, human activities associated with restoration efforts suggest a positive feedback as the stream restoration has focused effort on the basin beyond the reach. Ultimately, urban stream restoration remains a potentially useful management tool, but continued improvements in post‐project assessment should include examination of a wider range of indicators. 相似文献
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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
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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
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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
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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
60.
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