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671.
Evolutionary simulation-optimization (ESO) techniques can be adapted to model a wide variety of problem types in which system components are stochastic. Grey programming (GP) methods have been previously applied to numerous environmental planning problems containing uncertain information. In this paper, ESO is combined with GP for policy planning to create a hybrid solution approach named GESO. It can be shown that multiple policy alternatives meeting required system criteria, or modelling-to-generate-alternatives (MGA), can be quickly and efficiently created by applying GESO to this case data. The efficacy of GESO is illustrated using a municipal solid waste management case taken from the regional municipality of Hamilton-Wentworth in the Province of Ontario, Canada. The MGA capability of GESO is especially meaningful for large-scale real-world planning problems and the practicality of this procedure can easily be extended from MSW systems to many other planning applications containing significant sources of uncertainty. 相似文献
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Alfredo Mahar Lagmay Jerico Mendoz Fatima Cipriano Patricia Anne Delmendo Micah Nieves Lacsaman Marc Anthony Moises Nicanor Pellejera III Kenneth Ni?o Punay Glenn Sabio Laurize Santos Jonathan Serrano Herbert James Taniz Neil Eneri Tingin 《环境科学学报(英文版)》2017,29(9):39-47
Urban floods from thunderstorms cause severe problems in Metro Manila due to road traffic. Using Light Detection and Ranging (LiDAR)-derived topography, flood simulations and anecdotal reports, the root of surface flood problems in Metro Manila is identified. Majority of flood-prone areas are along the intersection of creeks and streets located in topographic lows. When creeks overflow or when rapidly accumulated street flood does not drain fast enough to the nearest stream channel, the intersecting road also gets flooded. Possible solutions include the elevation of roads or construction of well-designed drainage structures leading to the creeks. Proposed solutions to the flood problem of Metro Manila may avoid paralyzing traffic problems due to short-lived rain events, which according to Japan International Cooperation Agency (JICA) cost the Philippine economy 2.4 billion pesos/day. 相似文献
675.
No evidence for sperm priming responses under varying sperm competition risk or intensity in guppies
Jonathan P. Evans 《Die Naturwissenschaften》2009,96(7):771-779
Sperm competition theory predicts that males should tailor their investment in ejaculates according to the number of rival
males competing to fertilize a female’s eggs. Research spanning several taxa supports this prediction by showing that males
are often sensitive to the level of sperm competition and adjust their investment in sperm numbers accordingly. More recent
work has revealed that males may also tailor the quality of sperm according to the number of males competing for fertilization.
Here I test for both effects in guppies (Poecilia reticulata) in an experiment that simultaneously evaluates the risk and intensity models of sperm competition. The experiment determined
whether male guppies adjust the number (stripped ejaculate size) and quality (sperm velocity and viability) of sperm that
are primed over a 3-day period according to experimental changes in the perceived level of sperm competition. A total of 136
focal males were initially stripped of all retrievable sperm and assayed for these sperm traits before being allocated at
random to one of four treatments simulating different levels of sperm competition risk and intensity. During the 3-day treatment
phase, focal males had visual and olfactory access to a sexually receptive (initially virgin) female maintained with different
numbers of stimulus males to simulate variation in the risk and intensity of sperm competition. Following this, males were
assayed again for the sperm traits. Contrary to predictions, there was no significant change in any of the measured variables
among treatments, although qualitatively the patterns for sperm velocity and viability did conform to expectation. The lack
of any trend for the number of sperm primed was unequivocal and future work examining the effects of sperm competition on
sperm production should focus on whether males differentially allocate sperm numbers among matings that differ in the level
of sperm competition. 相似文献
676.
Governance and planning of ecosystem and water management within the California Bay-Delta, a critical component of California's water economy, have been characterized by a range of innovations in collaboration and conflict resolution. Despite legal mandates to incorporate environmental justice, the California Bay-Delta Authority's (CBDA) policy-development process and the subsequent Delta Vision process have systematically marginalized the role of environmental justice in California's water policy. We suggest that environmental justice in Bay-Delta planning can be understood as a “third party” with a tenuous seat at the CALFED water management table. As such environmental justice is a useful lens through which to assess the state's broader commitments and capacities relative to equity as a planning principal and outcome. We interpret the fate of environmental justice within Bay-Delta planning as indicative of the inherent tensions between systems based on increasing market dominance and state legitimation and the values of environmental justice based on distributive, procedural, and cognitive justice. We construct a model of marginalization and environmental injustice in collaborative planning to illustrate these tensions. We draw upon experiences of members of the Environmental Justice Sub-Committee of CBDA's Bay Delta Public Advisory Committee, as well as interviews with other key environmental justice interests, and a comprehensive review of internal and public CBDA documents relating to the environmental justice program including budgets and program plans, and ethnographic field work. We conclude that by learning from the mistakes of Bay-Delta planning, a positive model of collaborative, environmental justice-based planning for water and ecosystem management is possible. 相似文献
677.
Manuel R. Guariguata Jonathan P. Cornelius Bruno Locatelli Claudio Forner G. Arturo Sánchez-Azofeifa 《Mitigation and Adaptation Strategies for Global Change》2008,13(8):793-808
The relationship between tropical forests and global climate change has so far focused on mitigation, while much less emphasis
has been placed on how management activities may help forest ecosystems adapt to this change. This paper discusses how tropical
forestry practices can contribute to maintaining or enhancing the adaptive capacity of natural and planted forests to global
climate change and considers challenges and opportunities for the integration of tropical forest management in broader climate
change adaptation. In addition to the use of reduced impact logging to maintain ecosystem integrity, other approaches may
be needed, such as fire prevention and management, as well as specific silvicultural options aimed at facilitating genetic
adaptation. In the case of planted forests, the normally higher intensity of management (with respect to natural forest) offers
additional opportunities for implementing adaptation measures, at both industrial and smallholder levels. Although the integration
in forest management of measures aimed at enhancing adaptation to climate change may not involve substantial additional effort
with respect to current practice, little action appears to have been taken to date. Tropical foresters and forest-dependent
communities appear not to appreciate the risks posed by climate change and, for those who are aware of them, practical guidance
on how to respond is largely non-existent. The extent to which forestry research and national policies will promote and adopt
management practices in order to assist production forests adapt to climate change is currently uncertain. Mainstreaming adaptation
into national development and planning programs may represent an initial step towards the incorporation of climate change
considerations into tropical forestry. 相似文献
678.
Effects of initial resources on the development of strains during a stressful training situation: Some counterintuitive results
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Resource theories of occupational stress argue that employees' personal and environmental resources protect them from too much distress or strain during stressful work experiences. We examined four resources (emotional stability, previous experience, low drain on pre‐existing resources, and workgroup quality) available to soldiers at the beginning of a stressful 3‐month training experience as predictors of the trajectories of their strains over that period of time. Based on conservation of resources theory and the job demands–resources model, we predicted that the trends of strains would be more favorable (would increase more slowly or decline more quickly) if participants started the training with greater resources. The resources, primarily emotional stability and lack of pre‐existing resource drain, tended to be negatively related to strains, consistent with the idea that they can reduce strains. Significant interactions predicting trends were found predicting two of the three strains (post‐traumatic stress symptoms and depression, but not reports of physical health). Contrary to expectations, however, the three resources that significantly predicted trends over time (emotional stability, previous experience, and low pre‐existing resource drain) were associated with worsening rather than improving strains. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
679.
David W. Gibbons Chris Sandbrook William J. Sutherland Rezvin Akter Richard Bradbury Steven Broad Andy Clements Humphrey Q. P. Crick Joanna Elliott Ngawang Gyeltshen Melanie Heath Jonathan Hughes Richard K. B. Jenkins Alastair H. Jones Rocio Lopez de la Lama Nicholas B. W. Macfarlane Mike Maunder Ravikash Prasad Alfredo Romero-Muñoz Noa Steiner James Tremlett Rosie Trevelyan Savita Vijaykumar Irushinie Wedage Nancy Ockendon 《Conservation biology》2022,36(1):e13781
The COVID-19 pandemic has had an enormous impact on almost all aspects of human society and endeavor; the natural world and its conservation have not been spared. Through a process of expert consultation, we identified and categorized, into 19 themes and 70 subthemes, the ways in which biodiversity and its conservation have been or could be affected by the pandemic globally. Nearly 60% of the effects have been broadly negative. Subsequently, we created a compendium of all themes and subthemes, each with explanatory text, and in August 2020 a diverse group of experienced conservationists with expertise from across sectors and geographies assessed each subtheme for its likely impact on biodiversity conservation globally. The 9 subthemes ranked highest all have a negative impact. These were, in rank order, governments sidelining the environment during their economic recovery, reduced wildlife-based tourism income, increased habitat destruction, reduced government funding, increased plastic and other solid waste pollution, weakening of nature-friendly regulations and their enforcement, increased illegal harvest of wild animals, reduced philanthropy, and threats to survival of conservation organizations. In combination, these impacts present a worrying future of increased threats to biodiversity conservation but reduced capacity to counter them. The highest ranking positive impact, at 10, was the beneficial impact of wildlife-trade restrictions. More optimistically, among impacts ranked 11-20, 6 were positive and 4 were negative. We hope our assessment will draw attention to the impacts of the pandemic and, thus, improve the conservation community's ability to respond to such threats in the future. 相似文献
680.
Pantoja-Echevarría Laura María Tamburin Elena Elorriaga-Verplancken Fernando R. Marmolejo-Rodríguez Ana Judith Galván-Magaña Felipe Tripp-Valdez Arturo Lara Ariagna Jonathan M. P. Sujitha S. B. Delgado-Huertas Antonio Arreola-Mendoza Laura 《Environmental science and pollution research international》2022,29(41):61685-61697
Environmental Science and Pollution Research - Sharks are top predators and play an important role in the regulation of marine ecosystems at lower trophic position. Mustelus californicus, Sphyrna... 相似文献