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991.
Ayesha I. T. Tulloch Micha V. Jackson Elisa Bayraktarov Alexander R. Carey Diego F. Correa-Gomez Michael Driessen Ian C. Gynther Mel Hardie Katherine Moseby Liana Joseph Harriet Preece Andrés Felipe Suarez-Castro Stephanie Stuart John C. Z. Woinarski Hugh P. Possingham 《Conservation biology》2023,37(2):e14032
Monitoring is critical to assess management effectiveness, but broadscale systematic assessments of monitoring to evaluate and improve recovery efforts are lacking. We compiled 1808 time series from 71 threatened and near-threatened terrestrial and volant mammal species and subspecies in Australia (48% of all threatened mammal taxa) to compare relative trends of populations subject to different management strategies. We adapted the Living Planet Index to develop the Threatened Species Index for Australian Mammals and track aggregate trends for all sampled threatened mammal populations and for small (<35 g), medium (35–5500 g), and large mammals (>5500 g) from 2000 to 2017. Unmanaged populations (42 taxa) declined by 63% on average; unmanaged small mammals exhibited the greatest declines (96%). Populations of 17 taxa in havens (islands and fenced areas that excluded or eliminated introduced red foxes [Vulpes vulpes] and domestic cats [Felis catus]) increased by 680%. Outside havens, populations undergoing sustained predator baiting initially declined by 75% but subsequently increased to 47% of their abundance in 2000. At sites where predators were not excluded or baited but other actions (e.g., fire management, introduced herbivore control) occurred, populations of small and medium mammals declined faster, but large mammals declined more slowly, than unmanaged populations. Only 13% of taxa had data for both unmanaged and managed populations; index comparisons for this subset showed that taxa with populations increasing inside havens declined outside havens but taxa with populations subject to predator baiting outside havens declined more slowly than populations with no management and then increased, whereas unmanaged populations continued to decline. More comprehensive and improved monitoring (particularly encompassing poorly represented management actions and taxonomic groups like bats and small mammals) is required to understand whether and where management has worked. Improved implementation of management for threats other than predation is critical to recover Australia's threatened mammals. 相似文献
992.
Xingyue Qu Peihe Zhai Longqing Shi Xingwei Qu Ahmer Bilal Jin Han Xiaoge Yu 《Frontiers of Environmental Science & Engineering》2023,17(6):70
993.
基于RS与GIS功能互补性的震害评估方法浅析 总被引:1,自引:0,他引:1
震害评估是震后对建筑物和生命线工程等易损性,以及对人员伤亡和直接经济损失进行统计评估,实时有效的震灾评估是减少震灾损失的有力途径,意义重大。随着空间遥感技术以及计算机技术和图像处理技术的不断发展,基于数字图像处理的震害评估越来越得到广泛应用。在对RS和GIS技术的介绍的基础上,探讨了二者在震灾评估功能上的互补性,并以特定的方式相结合,建立了由四模块组成的基于RS和GIS的建筑物震害评估系统,得出基于震害提取的损失评估方法。基于震害指数的粗略评估和基于RS图像分类的精细评估方法结合运用,可以实时地、较准确地对建筑物震害损失进行评价。 相似文献
994.
995.
J. Purbolaksono J. Ahmad A. Khinani A.A. Ali A.Z. Rashid 《Journal of Loss Prevention in the Process Industries》2010,23(1):98-105
Increased temperature and decreased hardness values of the tube metal and development of oxide scale on the inner surface of boiler tubes over prolonged period of time are typical problems in power plants. Appropriate life assessments or condition monitoring of boiler tube should be carried out from time to time. Computer simulations may economically support the post-failure assessment method, i.e. visual inspections, metallurgical examinations and mechanical strength measurements. However, estimations obtained from the simulations may provide an advanced warning to take preventive actions prior to failure. In this work two failure cases of the reheater and superheater tubes made of a typical material of SA213-T22 steel are evaluated. As the oxide scales are increasingly developed on the inner surface, the increasing of temperature and decreasing of hardness value in tube metal for both cases are determined. The remnant life estimations are then made in the form of creep cumulative damages. 相似文献
996.
Functional Ecosystems and Biodiversity Buzzwords 总被引:1,自引:0,他引:1
Paul Z. Goldstein 《Conservation biology》1999,13(2):247-255
Abstract: Several increasingly popular paradigms in conservation remove organismal information and life-history requirements from management planning with claims that species-specific information is not necessary to the understanding and management of "ecosystem function" and may therefore be discarded. Although several authors have called attention to the fact that ecosystem management has not yet been articulated sufficiently to comprise an adequate paradigm for wildlife protection, there has been a series of suggestions paralleling ecosystem management's popularity that the perceived or imagined emergent properties of communities should be at the root of conservation planning. Such reductions most commonly take the form of abstracted species diversity measures that may be irrelevant or misleading with respect to site-specific planning and to the monitoring of specific management treatments. Following earlier examinations of ecosystem management, I emphasize that several of its apparent outgrowths may be too vague to inform specific recommendations, that the historical mechanics of "ecosystem processes" are essentially unknowable, and that anecdotal definitions of ecosystems allow one to justify virtually any protocol as management. The primacy of process-dependent, landscape-functional considerations in conservation planning is specious in the absence of species- and population-specific information, which should form the foundation for understanding such processes in the first place. Only by viewing nature in terms of the relationships between processes and organisms, rather than in terms of emergent properties of organismal assemblages or abiotic factors divorced from organismal data, can conservation plans claim to protect biological elements. 相似文献
997.
Shan Y Feng Z Izuta T Aoki M Totsuka T 《Environmental pollution (Barking, Essex : 1987)》1996,91(3):355-361
The seedlings of Pinus armandi Franch. were exposed to ozone (O(3)) at 300 ppb for 8 h a day, 6 days a week, and simulated acid rain of pH 3.0 or 2.3, 6 times a week, alone or in combination, for 14 weeks from 15 June to 20 September 1993. The control seedlings were exposed to charcoal-filtered air and simulated rain of pH 6.8 during the same period. Significant interactive effects of O(3) and simulated acid rain on whole plant net photosynthetic rate were observed, but not on other determined parameters. The exposure of the seedlings to O(3) caused the reductions in the dry weight growth, root dry weight relative to the whole plant dry weight, net photosynthetic rate, transpiration rate in light, water-use efficiency and root respiration activity, and increases in shoot/root ratio, and leaf dry weight relative to the whole plant dry weight without an appearance of acute visible foliar injury, but did not affect the dark respiration rate and transpiration rate in the darkness. The decreased net photosynthetic rate was considered to be the major cause for the growth reduction of the seedlings exposed to O(3). On the other hand, the exposure of the seedlings to simulated acid rain reduced the net photosynthetic rate per unit chlorophyll a + b content, but did not induce the significant change in other determined parameters. 相似文献
998.
Productivity in Conservation Research in the Southern Hemisphere 总被引:2,自引:0,他引:2
Elissa Z. Cameron 《Conservation biology》2008,22(2):232-233
999.
Kumar Anuj Ingle Anjali Shende Diwakar Z. Wasewar Kailas L. 《Environmental science and pollution research international》2023,30(10):24890-24898
Environmental Science and Pollution Research - Levulinic acid is a carboxylic acid present in industrial downstream. It is an important chemical and can be transformed into various important... 相似文献
1000.
Zhai Yuanzheng Ma Tianyi Zhou Jingjing Li Xiaofei Liu Dan Wang Zhuo Qin Yunqi Du Qingqing 《Environmental science and pollution research international》2019,26(6):5713-5723
Environmental Science and Pollution Research - Colloids associated with heavy metals are ubiquitous in contaminated groundwater; waste accumulation at imperfectly sealed landfills can produce large... 相似文献