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401.
Graham Heaslip Alain Vaillancourt Peter Tatham Gyngyi Kovcs Deborah Blackman Marian Crowley Henry 《Disasters》2019,43(3):686-708
The continuing incidence of disasters and their associated challenges has increased the demand for humanitarian logisticians. However, there is a dearth of research on their essential competencies. This paper proposes, therefore, a humanitarian logistics competency framework (HlCF) to assist with the professional development of humanitarian logisticians. In creating the HlCF, nine competency domains containing 29 specific competencies across four levels (entry to senior management) were identified. This study makes two key contributions to the literature: (i) it extends the discussion of competency frameworks in humanitarian logistics; and (ii) it presents a framework designed to support the human resource plans and practices of aid agencies. The HlCF allows not only individual humanitarian logisticians to develop the competencies necessary for career success, but also humanitarian organisations to map their own competency frameworks to a common standard. This will, in turn, facilitate workforce mobility and support the overall concept of a certified humanitarian logistics professional. 相似文献
402.
Earl D. McCoy Katherine A. Basiotis Kevin M. Connor Henry R. Mushinsky 《Behavioral ecology and sociobiology》2013,67(5):815-821
Habitat selection requires choice, which differentiates it from habitat use, and choice, in turn, is dependent upon the responses of organisms to the environmental, social, and other cues that they perceive. Habitat selection by the gopher tortoise (Gopherus polyphemus) was investigated by translocating tortoises and monitoring their movements within two sites in central Florida. The first site supported a stable preponderance of high-quality habitat, and tortoises avoided areas with a dense tree canopy cover caused by fire exclusion. The second site was badly invaded by an introduced weed, and tortoises avoided areas where the weed had formed a dense monoculture. At both sites, individuals appeared to be responding to visual cues to avoid areas that were relatively dark. In landscapes with relatively large amounts of high-quality habitat, this avoidance behavior serves the gopher tortoise well by keeping individuals within the dominant habitat type. In degraded areas, high-quality habitat often becomes increasingly uncommon, and the avoidance behavior exhibited by the tortoises will result in individuals becoming confined to small patches, causing a significant reduction in fitness and hence questioning their long-term survival in such areas. The results from our study show that in order to maintain viable tortoise populations in areas increasingly subjected to human fragmentation and degradation, it is crucial not only to suppress tree canopy cover continually and prevent invasion by exotic weeds, but also to be mindful that the avoidance behavior of the gopher tortoise could prevent individuals from fully occupying a high-quality habitat in response to restoration and management efforts. 相似文献
403.
Processing of allochthonous macrophyte subsidies by sandy beach consumers: estimates of feeding rates and impacts on food resources 总被引:1,自引:0,他引:1
Mariano Lastra Henry M. Page Jenifer E. Dugan David M. Hubbard Ivan F. Rodil 《Marine Biology》2008,154(1):163-174
Allochthonous subsidies of organic material can profoundly influence population and community structure; however, the role
of consumers in the processing of these inputs is less understood but may be closely linked to community and ecosystem function.
Inputs of drift macrophytes subsidize sandy beach communities and food webs in many regions. We estimated feeding rates of
dominant sandy beach consumers, the talitrid amphipods (Megalorchestia corniculata, in southern California, USA, and Talitrus saltator, in southern Galicia, Spain), and their impacts on drift macrophyte subsidies in field and laboratory experiments. Feeding
rate varied with macrophyte type and, for T. saltator, air temperature. Size-specific feeding rates of talitrid amphipods were greatest on brown macroalgae (Macrocystis, Egregia, Saccorhiza and Fucus). Rates for large individuals of both species ranged from ∼40 mg wet wt individual−112 h−1 on brown macroalgae to negligible feeding by M. corniculata on a vascular plant (surfgrass). Amphipod growth rates were also greatest on Macrocystis and lowest on surfgrass, Phyllospadix. For a Californian beach with substantial inputs of macrophyte wrack (>70 kg wet wt m−1 month−1 in summer), we estimated that the population of talitrid amphipods could process an average of 55% of the palatable Macrocystis input. Our results indicate that talitrid amphipod populations can have a significant impact on drift macrophyte processing
and fate and that the quantity and composition of drift macrophytes could, in turn, limit populations of beach consumers. 相似文献
404.
Episodic death across species of desert shrubs 总被引:2,自引:0,他引:2
Extreme events shape population and community trajectories. We report episodic mortality across common species of thousands of long-lived perennials individually tagged and monitored for 20 years in the Colorado Desert of California following severe regional drought. Demographic records from 1984 to 2004 show 15 years of virtual stasis in populations of adult shrubs and cacti, punctuated by a 55-100% die-off of six of the seven most common perennial species. In this episode, adults that experienced reduced growth in a lesser drought during 1984-1989 failed to survive the drought of 2002. The significance of this event is potentially profound because population dynamics of long-lived plants can be far more strongly affected by deaths of adults, which in deserts potentially live for centuries, than by seedling births or deaths. Differential mortality and rates of recovery during and after extreme climatic events quite likely determine the species composition of plant and associated animal communities for at least decades. The die-off recorded in this closely monitored community provides a unique window into the mechanics of this process of species decline and replacement. 相似文献
405.
Colonial epifauna are vulnerable to the effects of bottom fishing, but impacts on the life histories of these non-target animals have not been examined extensively. Dredging potentially impairs sexual reproduction by invoking regeneration and induces clonality by severing colonies or through the abortion of damaged modules. This study investigated the potential for commercial-scale scallop dredging to alter sexual and asexual (clonal) reproduction in the hydroid Sertularia cupressina. In total, 1,071 colonies from 104 epizoic microhabitats (upper valves of live scallops relatively undisturbed by fishing) and 75 epilithic microhabitats (cobbles more severely disturbed by fishing) were collected from 53 to 94-m depths in the Bay of Fundy (Atlantic Canada). Colony abundance, injury frequency (proportion of colonies with sealed, snapped off stems), percentage of fertile colonies and sexual fecundity (number of gonophores and gonophore dimensions) were measured on all substrata. Ten randomly amplified polymorphic DNA (RAPD) primers were used to estimate clonal diversity. Field experiments found no significant effect of microhabitat differences between scallop and cobble substrata on fecundity and clonality in S. cupressina, while experimentally-induced injuries suppressed the percent of fertile colonies. On the fishing grounds, colonies on scallop valves were more abundant and sexually fertile than their counterparts on cobble, and all were sexually derived. In contrast, colonies on cobbles had a greater percentage of injury, were less fertile and were frequently clonally-derived. Impacts of fishing-related injuries on reproduction in colonial epifauna have been overlooked, yet the long-term consequences of such impacts could result in reduced adaptability, recruitment and recovery potential of these and dependent organisms.Communicated by R.J. Thompson, St. Johns 相似文献
406.
407.
In 1994, the U.S. Department of Energy (DOE) initiated a contract reform program intended to strengthen oversight capabilities and encourage the creation of contract and incentive structures, which would effectively facilitate the treatment of onsite contamination and waste. The remedia‐tion and disposal of these legacy wastes is the core of the Department's environmental manage‐ment mission (Government Accountability Office [GAO], 2003). Despite a concerted effort toward achieving the goals of the reform, progress has been slow. Many projects continue to necessitate cost and time extensions above those originally agreed upon. Although the Department insti‐tuted an accelerated cleanup program in 2002, promising to shave some $50 billion and 35 years from its earlier cost and schedule projections, there have been delays in critical project areas that call into question the attainability of the proposed reductions (GAO, 2005). Numerous explana‐tions have been offered as to why achieving these goals has proven so difficult, many of which have concluded that flawed contracting practices are to blame. This article concludes that the root of the problem is much deeper and that the organizational criticisms aimed at DOE are as much a legacy as the waste itself. Although the focus of this article is on large former nuclear weapons sites, these types of contracting and organizational issues are often found at other gov‐ernment and private complex hazardous waste sites. © 2006 Wiley Periodicals, Inc. 相似文献
408.
The Consortium for Risk Evaluation with Stakeholder Participation (CRESP) was asked by the United States Department of Energy (US DOE) to consider the root causes of remediation projects that fail to entirely achieve their goals and then to offer suggestions to assist the Department. To begin this project, CRESP held several meetings at which the group defined problematic outcomes, the early symptoms of problematic outcomes, and the root causes of failing to meet expectations. The five root causes are complex science, engineering, and technology; ambiguous economics; project management shortcomings; political processes and credibility; and history and organizational culture. This article, while focusing on the US DOE, provides a larger context for many remediation projects that have failed to entirely live up to their sponsors' expectations. © 2007 Wiley Periodicals, Inc. 相似文献
409.
/ The management of riverine wetlands, recognized as a major component of biodiversity in fluvial hydrosystems, is problematic. Preservation or restoration of such ecosystems requires a method to assess the major ecological processes operating in the wetlands, the sustainability of the aquatic stage, and the restoration potential of each riverine wetland. We propose a method of diagnosis based on aquatic macrophytes and helophytes. Plant communities are used because they are easy to survey and provide information about (1) the origin of a water supply (i.e., groundwater, seepage, or surface river water) and its nutrient content, (2) effects of flood disturbances, and (3) terrestrialization processes. The novelty of the method is that, in contrast to available typologies, it is based on the interference of gradients resulting from several processes, which makes it possible to predict wetland sustainability and restoration potential. These predictions result from knowledge of the processes involved in terrestrialization, i.e., the influence of flood disturbances, occurrence of groundwater supplies, trophic degree, and water permanency of the habitat during a yearly cycle. The method is demonstrated on five different river systems. 相似文献
410.
Parviz MohammadiShaliza Ibrahim Mohamad Suffian Mohamad Annuar Sean Law 《Journal of Cleaner Production》2011,19(14):1654-1658
Effects of different pretreatment methods on sludge inocula were evaluated with respect to hydrogen (H2) production enhancement using palm oil mill effluent (POME) in a batch system. The experimental results showed that the pretreatment methods (chemical, acid, heat-shock, freezing and thawing, and base) at 35 °C and initial pH 5.5 had a positive influence on H2 production yield and chemical oxygen demand (COD) removal efficiency during the fermentative H2 production as compared to the control experiments (without pretreatment). Heat-shock pretreatment method was shown to be a simple and useful method for enhancing both H2 producing and COD removal processes from POME with highest H2 yield and COD removal efficiency at 0.41 mmol H2/g COD and 86%, respectively. 相似文献