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Conservation operates within complex systems with incomplete knowledge of the system and the interventions utilized. This frequently results in the inability to find generally applicable methods to alleviate threats to Earth's vanishing wildlife. One approach used in medicine and the social sciences has been to develop a deeper understanding of positive outliers. Where such outliers share similar characteristics, they may be considered exceptional responders. We devised a 4‐step framework for identifying exceptional responders in conservation: identification of the study system, identification of the response structure, identification of the threshold for exceptionalism, and identification of commonalities among outliers. Evaluation of exceptional responders provides additional information that is often ignored in randomized controlled trials and before–after control‐intervention experiments. Interrogating the contextual factors that contribute to an exceptional outcome allow exceptional responders to become valuable pieces of information leading to unexpected discoveries and novel hypotheses. 相似文献
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I. A. Papazoglou O. N. Aneziris J. G. Post B. J. M. Ale 《Journal of Loss Prevention in the Process Industries》2002,15(6):545-554
This paper presents the technical model of an Integrated Quantitative Risk Assessment method, taking into account management as well as technical design and producing risk level measures. The basic steps of the technical model consist in developing a Master Logic Diagram (MLD) delineating the major immediate causes of Loss of Containment and associated quantitative models for assessing their frequency. Appropriate management models quantify the parameters of the technical model on the basis of the safety management system of the installation. The methodology is exemplified through its application on the risk assessment of a LPG scrubbing tower of an oil refinery. A detailed technical model simulating the response of the system to various initiating events is developed, along with a detailed model simulating the influence of the plant-specific management and organizational practices. The overall effect is quantified through the frequency of release of LPG as a result of a Loss of Containment in scrubbing towers of the refinery. 相似文献
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Summary In the laboratory overwintered females of Polistes fuscatus preferentially associated with former nestmates during the founding of a colony. They did not associate with non-nestmates or only with nestmates with whom they had overwintered, but affiliated with all former nestmates, regardless of where the former nestmates overwintered. 相似文献
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Summary Sharp-tailed sparrows Ammospiza caudacuta and seaside sparrows A. maritima co-occupy salt marshes in northeastern North America and are ecologically similar. Female caudacuta care for their young unaided, in comparison to martima's dual parental behavior. The annual reproductive effort of female caudacuta is higher than that of female maritima. Under reproductive effort theory, as both species' reproductive output is the same, female caudacuta should have a lower probability of survival than female maritima. However, the annual survival of both groups was the same. We believe that these results are possible only in highly productive habitats, where the relative cost differences of derived and ancestral mating systems may not be as great as in less productive environments. Lack of penalty in terms of lifetime fitness may have set the stage for the evolution of promiscuity in the sharp-tailed sparrow.In spite of their emancipation from parental duties, male caudacuta survive no better than females. We conclude that activities not directly related to care of young, such as patrolling large home ranges, may entail as much risk or energy expenditure as parental duties do. 相似文献
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Ecological theory predicts that low productivity systems should have low biodiversity. However, despite the oligotrophic status
of the Gulf of Aqaba (Northern Red Sea) ciliate species richness was unexpectedly high. In addition, phytoplankton, as main
ciliate prey, was made up by only few genera, indicating a significant niche overlap among the grazers. Up to 97% of the ciliates
were from the same taxonomic group and of the same size range, implying very similar food niches. Ciliate diversity was highest
at times of lowest chlorophyll concentrations, during the period of stable abiotic conditions, but relatively high genetic
diversity within the ciliate prey, notably among the cyanobacteria Synechococcus and Prochlorococcus. In the absence of disturbance and with little predation pressure, the alternate explanations for the observed ciliate diversity
are either very fine niche partitioning by the ciliates, or their competitive equivalence resulting in a random assortment
of species immigrating from a larger metacommunity, in accordance with Hubbell’s, (The unified neutral theory of biodiversity
and biogeography. Princeton University Press, Princeton, 2001) neutral model. While the use of species abundance distributions (SAD’s) is far from definitive, the theoretical SAD’s that
best fit the Gulf of Aqaba ciliate data was most often not that expected by neutral theory. 相似文献
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Matthew A. Etterson Susan N. Ellis-FelegeDavid Evers Gilles GauthierJoseph A. Grzybowski Brady J. MattssonLaura R. Nagy Brian J. OlsenCraig M. Pease Max Post van der BurgAaron Potvien 《Ecological modelling》2011,222(14):2178-2190
Fecundity is fundamental to the fitness, population dynamics, conservation, and management of birds. For all the efforts made to measure fecundity or its surrogates over the past century of avian research, it is still mismeasured, misrepresented, and misunderstood. Fundamentally, these problems arise because of partial observability of underlying processes such as renesting, multiple brooding, and temporary emigration. Over the last several decades, various analytical approaches have been developed to estimate fecundity from incomplete and biased data. These, include scalar arithmetic formulae, partial differential equations, individual-based simulations, and Markov chain methodology. In this paper, we: (1) identify component processes of avian reproduction; (2) review existing methods for modeling fecundity; (3) place these diverse models under a common conceptual framework; (4) describe the parameterization, validation, and limitations of such models; and (5) point out future considerations and challenges in the application of fecundity models. We hope this synthesis of existing literature will help direct researchers toward the most appropriate methods to assess avian reproductive success for answering questions in evolutionary ecology, natural history, population dynamics, reproductive toxicology, and management. 相似文献