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781.
Graham W. Prescott William J. Sutherland Daniel Aguirre Matthew Baird Vicky Bowman Jake Brunner Grant M. Connette Martin Cosier David Dapice Jose Don T. De Alban Alex Diment Julia Fogerite Jefferson Fox Win Hlaing Saw Htun Jack Hurd Katherine LaJeunesse Connette Felicia Lasmana Cheng Ling Lim Antony Lynam Aye Chan Maung Benjamin McCarron John F. McCarthy William J. McShea Frank Momberg Myat Su Mon Than Myint Robert Oberndorf Thaung Naing Oo Jacob Phelps Madhu Rao Dietrich Schmidt‐Vogt Hugh Speechly Oliver Springate‐Baginski Robert Steinmetz Kirk Talbott Maung Maung Than Tint Lwin Thaung Salai Cung Lian Thawng Kyaw Min Thein Shwe Thein Robert Tizard Tony Whitten Guy Williams Trevor Wilson Kevin Woods Alan D. Ziegler Michal Zrust Edward L. Webb 《Conservation biology》2017,31(6):1257-1270
Political and economic transitions have had substantial impacts on forest conservation. Where transitions are underway or anticipated, historical precedent and methods for systematically assessing future trends should be used to anticipate likely threats to forest conservation and design appropriate and prescient policy measures to counteract them. Myanmar is transitioning from an authoritarian, centralized state with a highly regulated economy to a more decentralized and economically liberal democracy and is working to end a long‐running civil war. With these transitions in mind, we used a horizon‐scanning approach to assess the 40 emerging issues most affecting Myanmar's forests, including internal conflict, land‐tenure insecurity, large‐scale agricultural development, demise of state timber enterprises, shortfalls in government revenue and capacity, and opening of new deforestation frontiers with new roads, mines, and hydroelectric dams. Averting these threats will require, for example, overhauling governance models, building capacity, improving infrastructure‐ and energy‐project planning, and reforming land‐tenure and environmental‐protection laws. Although challenges to conservation in Myanmar are daunting, the political transition offers an opportunity for conservationists and researchers to help shape a future that enhances Myanmar's social, economic, and environmental potential while learning and applying lessons from other countries. Our approach and results are relevant to other countries undergoing similar transitions. 相似文献
782.
783.
Ryan A. Chisholm Xingli Giam Keren R. Sadanandan Tak Fung Frank E. Rheindt 《Conservation biology》2016,30(3):610-617
How many species have gone extinct in modern times before being described by science? To answer this question, and thereby get a full assessment of humanity's impact on biodiversity, statistical methods that quantify undetected extinctions are required. Such methods have been developed recently, but they are limited by their reliance on parametric assumptions; specifically, they assume the pools of extant and undetected species decay exponentially, whereas real detection rates vary temporally with survey effort and real extinction rates vary with the waxing and waning of threatening processes. We devised a new, nonparametric method for estimating undetected extinctions. As inputs, the method requires only the first and last date at which each species in an ensemble was recorded. As outputs, the method provides estimates of the proportion of species that have gone extinct, detected, or undetected and, in the special case where the number of undetected extant species in the present day is assumed close to zero, of the absolute number of undetected extinct species. The main assumption of the method is that the per‐species extinction rate is independent of whether a species has been detected or not. We applied the method to the resident native bird fauna of Singapore. Of 195 recorded species, 58 (29.7%) have gone extinct in the last 200 years. Our method projected that an additional 9.6 species (95% CI 3.4, 19.8) have gone extinct without first being recorded, implying a true extinction rate of 33.0% (95% CI 31.0%, 36.2%). We provide R code for implementing our method. Because our method does not depend on strong assumptions, we expect it to be broadly useful for quantifying undetected extinctions. 相似文献
784.
Combining steam injection with hydraulic fracturing for the in situ remediation of the unsaturated zone of a fractured soil polluted by jet fuel 总被引:1,自引:0,他引:1
Nilsson B Tzovolou D Jeczalik M Kasela T Slack W Klint KE Haeseler F Tsakiroglou CD 《Journal of environmental management》2011,92(3):695-707
A steam injection pilot-scale experiment was performed on the unsaturated zone of a strongly heterogeneous fractured soil contaminated by jet fuel. Before the treatment, the soil was stimulated by creating sub-horizontal sand-filled hydraulic fractures at three depths. The steam was injected through one hydraulic fracture and gas/water/non-aqueous phase liquid (NAPL) was extracted from the remaining fractures by applying a vacuum to extraction wells. The injection strategy was designed to maximize the heat delivery over the entire cell (10 m × 10 m × 5 m). The soil temperature profile, the recovered NAPL, the extracted water, and the concentrations of volatile organic compounds (VOCs) in the gas phase were monitored during the field test. GC-MS chemical analyses of pre- and post-treatment soil samples allowed for the quantitative assessment of the remediation efficiency. The growth of the heat front followed the configuration of hydraulic fractures. The average concentration of total hydrocarbons (g/kg of soil) was reduced by ~ 43% in the upper target zone (depth = 1.5-3.9 m) and by ~ 72% over the entire zone (depth = 1.5-5.5 m). The total NAPL mass removal based on gas and liquid stream measurements and the free-NAPL product were almost 30% and 2%, respectively, of those estimated from chemical analyses of pre- and post-treatment soil samples. The dominant mechanisms of soil remediation was the vaporization of jet fuel compounds at temperatures lower than their normal boiling points (steam distillation) enhanced by the ventilation of porous matrix due to the forced convective flow of air. In addition, the significant reduction of the NAPL mass in the less-heated deeper zone may be attributed to the counter-current imbibition of condensed water from natural fractures into the porous matrix and the gravity drainage associated with seasonal fluctuations of the water table. 相似文献
785.
Livestock's contributions to climate change and smog-forming emissions are a growing public policy concern. This study quantifies greenhouse gas (GHG) and alcohol emissions from calves and feedlot steers. Carbon dioxide (CO) methane (CH), nitrous oxide (NO), ethanol (EtOH), and methanol (MeOH) were measured from a total of 45 Holstein and Angus steers and 9 Holstein calves representative of four different growth stages commonly present on calf ranches and commercial feedlots. Individuals from each animal type were randomly assigned to three equal replicate groups of nine animals per group. Steers were fed a high concentrate diet and calves a milk replacer and grain supplement. Cattle and calves were housed in groups of three animals in an environmental chamber for 24 h. The CO, NO, EtOH, and MeOH concentrations from the air inlet and outlet of the chamber were measured using an INNOVA 1412 monitor and CH using a TEI 55C methane analyzer. Emission rates (g head h) were calculated. The GHGs were mainly produced by enteric fermentation and respiration and differed across life stages of cattle. Compared with dairy cows, feedlot steers produce relatively less GHG. In general, ethanol and methanol, the most important volatile organic compound (VOC) group in the dairy sector, were below the lower limit of detection of the gas analyzer. The present data will be useful to verify models and to enhance GHG emission inventories for enteric fermentation, respiration, and fresh excreta for numerous cattle life stages across the beef industry. 相似文献
786.
Frank Kupper Tjard De Cock Buning 《Journal of Agricultural and Environmental Ethics》2011,24(5):431-450
Debates in animal ethics are largely characterized by ethical monism, the search for a single, timeless, and essential trait
in which the moral standing of animals can be grounded. In this paper, we argue that a monistic approach towards animal ethics
hampers and oversimplifies the moral debate. The value pluralism present in our contemporary societies requires a more open
and flexible approach to moral inquiry. This paper advocates the turn to a pragmatic, pluralistic approach to animal ethics.
It contributes to the development of such an approach in two ways. It offers a pragmatist critique of ethical monism in animal
ethics and presents the results of a qualitative study into the value diversity present in the different ways of thinking
about animals in the Netherlands. Carefully arranged group discussions resulted in the reconstruction of four distinctive
moral value frameworks that may serve as instruments in the future process of moral inquiry and deliberation in the reflection
on animal use. 相似文献
787.
Bénédicte Ritt Catherine Pierre Olivier Gauthier Frank Wenzhöfer Antje Boetius Jozée Sarrazin 《Marine Biology》2011,158(6):1187-1210
The Nile Deep-Sea Fan (NDSF) is located on the passive continental margin off Egypt and is characterized by the occurrence
of active fluid seepage such as brine lakes, pockmarks and mud volcanoes. This study characterizes the structure of faunal
assemblages of such active seepage systems of the NDSF. Benthic communities associated with reduced, sulphidic microhabitats
such as sediments and carbonate crusts were sampled by remotely operated vehicles during two cruises in 2006 (BIONIL) and
2007 (MEDECO). Environmental conditions and biological factors including family-level faunal composition, density and diversity
were measured at local and regional scales. Significant differences were detected at different spatial scales: (1) the fauna
of reduced habitats differed substantially in activity, diversity and biomass from the non-seep environment at similar water
depth, (2) cold seep microhabitats showed differences in community structure and composition related to substratum type as
well as to the intensity and location of fluid emissions. 相似文献
788.
This study presents information on the design and creation of a standard operation procedure (SOP) for psychiatric service after an earthquake. The strategies employed focused on the detection of survivors who developed persistent psychiatric illness, particularly post-traumatic stress and major depressive disorders. In addition, the study attempted to detect the risk factors for psychiatric illness. A Disaster-Related Psychological Screening Test (DRPST) was designed by five psychiatrists and two public health professionals for rapidly and simply interviewing 4,223 respondents within six months of the September 1999 Chi-Chi earthquake. A SOP was established through a systemic literature review, action research, and two years of data collection. Despite the limited time and resources inherent to a disaster situation, it is necessary to develop an SOP for psychiatric service after an earthquake in order to assist the high number of survivors suffering from subsequent psychiatric impairment. 相似文献
789.
Problem
While observational before-after studies are considered the industry standard for developing crash modification factors (CMFs), there are practical limitations that may preclude their use in highway safety analysis. There is a need to explore alternative methods for estimating CMFs.Method
This paper employs case-control and cross-sectional analyses to estimate CMFs for fixed roadway lighting and the allocation of lane and shoulder widths.Results
Based on the case-control method, the CMF for intersection lighting is 0.886, while the cross-sectional study indicates a CMF of 0.881. The CMFs developed for lane and shoulder widths are also similar when comparing the two methods.Conclusions
This paper suggests that case-control and cross-sectional studies produce consistent results if care is taken in the study design and model development.Impact on industry
Case-control and cross-sectional studies may provide a viable alternative to estimate CMFs when a before-after study is impractical due to data restrictions. 相似文献790.