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141.
142.
Optimization of the Resources Management in Fighting Wildfires 总被引:1,自引:0,他引:1
Wildfires lead to important economic, social, and environmental losses, especially in areas of Mediterranean climate where
they are of a high intensity and frequency. Over the past 30 years there has been a dramatic surge in the development and
use of fire spread models. However, given the chaotic nature of environmental systems, it is very difficult to develop real-time
fire-extinguishing models. This article proposes a method of optimizing the performance of wildfire fighting resources such
that losses are kept to a minimum. The optimization procedure includes discrete simulation algorithms and Bayesian optimization
methods for discrete and continuous problems (simulated annealing and Bayesian global optimization). Fast calculus algorithms
are applied to provide optimization outcomes in short periods of time such that the predictions of the model and the real
behavior of the fire, combat resources, and meteorological conditions are similar. In addition, adaptive algorithms take into
account the chaotic behavior of wildfire so that the system can be updated with data corresponding to the real situation to
obtain a new optimum solution. The application of this method to the Northwest Forest of Madrid (Spain) is also described.
This application allowed us to check that it is a helpful tool in the decision-making process. 相似文献
143.
Leonardo?Alberto?Rios?OsorioEmail author Manuel?Ortiz?Lobato Xavier?álvarez?Del?Castillo 《Environment, Development and Sustainability》2005,7(4):501-518
The paper analyzes the concept of sustainable development in the light of the different interpretations existing on the issue
since its appearance and establishment as an ideal to lead humanity’s line of progress. Within these interpretations, a characteristic
generation of diverse debates can be appreciated, arising from different perspectives, academic as well as ideological, aiming
at describing, clarifying and determining their conceptual reach.
Based on these facts a model of categorization for these debates has developed, a model in which interpretations generated
on the concept of sustainable development were catalogued into four realms: conceptual, contextual, academic and geopolitical.
The configuration of these four areas of debate, as well as the recognition of the diversity of interpretations existing on
sustainable development, is a reflection of the intrinsic complexity of the phenomena, which affect the natural and social
world, both at the local and global level. The analysis of this complexity is based on the subjectivity, which is inherent
to the interpretation of these phenomena, with permanent reference to the cultural context from which the diverse discourses
were structured.
This global perspective on the state-of-the-art controversy concerning the idea of sustainable development as an articulatory
axis reveals the necessity of building epistemological models, which can give a new direction to scientific research. From
these new models, based on the analysis of the holistic character of reality, the subjective and the objective must be integrated
in the generation of knowledge, which contributes usefully to the unceasing reconstruction of our world-(view).
Readers should send their comments on this paper to: BhaskarNath@aol.com within 3 months of publication of this issue. 相似文献
144.
José Luis Carballo Enrique Ávila Susana Enríquez Leonardo Camacho 《Marine Biology》2006,148(3):467-478
The mutualistic association between the sponge Haliclona caerulea and the calcareous red macroalga Jania adherens is conspicuous on shallow rocky regions of Mazatlán Bay (eastern tropical Pacific, Mexico). Transplanting experiments were
carried out to examine the morphological responses of the association to an environmental depth gradient. Simultaneously,
we conducted caging experiments to examine the effects of predation (mainly by angelfishes) on association morphology. For
this, we transplanted specimens of the association from a control area at 3 m depth to depths of 1 and 5 m, and measured the
morphological responses in the association (macro- and microstructure) from the three sites before and after 103 days. The
association had the capacity to adjust both macro and micromorphologically, and both external morphology and body structure
changed significantly with depth. The specimens grown at 1 m developed a larger surface area of attachment, higher organic
density and higher inorganic content than the control specimens at 3 m, and the organisms grown at 5 m depth. We also detected
significant differences in the aquiferous system of the sponge, which developed smaller and more numerous oscula at 1 m than
at 5 m depth. These differences seem to be consistent with the wave movement as one of the main regulatory factors of the
morphology of the association. However, the spicules from H. caerulea were most slender in shallow water, which is not consistent with increasing robustness in the face of greater wave force.
The algal skeleton supplied up to 27% of the total inorganic structure of the association; thus, algal contribution significantly
reduces the energy costs of spicule production, specifically under high wave exposure, when H. caerulea requires structural reinforcement relative to organic content. The contribution of the sponge to the association (as ratio
Si to CaCO3) increased significantly from 3 to 5 m (12% in the uncaged specimens and 22% in the caged specimens), showing that the mutualistic
relationship decreases with depth. The production of sponge branches in caged individuals was the most notable difference
from uncaged morphs, which could suggest the effect of predators like angelfishes. However, branches could also be a response
to the reduction in water movement and irradiance inside the cages. Sponges are known to show morphological acclimation in
response to habitat variation, but this is the first study to show it in a sponge living in association with a macroalga. 相似文献
145.
Péter László Pap Gábor Árpád Czirják Csongor István Vágási Zoltán Barta Dennis Hasselquist 《Die Naturwissenschaften》2010,97(10):891-901
Difference between sexes in parasitism is a common phenomenon among birds, which may be related to differences between males and females in their investment into immune functions or as a consequence of differential exposure to parasites. Because life-history strategies change sex specifically during the annual cycle, immunological responses of the host aiming to reduce the impact of parasites may be sexually dimorphic. Despite the great complexity of the immune system, studies on immunoecology generally characterise the immune status through a few variables, often overlooking potentially important seasonal and gender effects. However, because of the differences in physiological and defence mechanisms among different arms of the immune system, we expect divergent responses of immune components to environmental seasonality. In male and female house sparrows (Passer domesticus), we measured the major components of the immune system (innate, acquired, cellular and humoral) during four important life-history stages across the year: (1) mating, (2) breeding, (3) moulting and (4) during the winter capture and also following introduction to captivity in aviary. Different individuals were sampled from the same population during the four life cycle stages. We found that three out of eight immune variables showed a significant life cycle stage × sex interaction. The difference in immune response between the sexes was significant in five immune variables during the mating stage, when females had consistently stronger immune function than males, while variables varied generally non-significantly with sex during the remaining three life cycle stages. Our results show that the immune system is highly variable between life cycle stages and sexes, highlighting the potential fine tuning of the immune system to specific physiological states and environmental conditions. 相似文献
146.
Soledad Puente Humberto Marín Pamela P. lvarez Pablo M. Flores Daniela Grassau 《Disasters》2019,43(3):555-574
This paper reviews the role of news with respect to the mental health of a population exposed to a disaster. It is based on the five essential elements of psychosocial care presented by Stevan E. Hobfoll et al. (2007) that can be introduced after a potentially traumatic event: promoting a sense of safety, calming, self and collective efficacy, connectedness, and hope. This study developed a method to relate these elements to television coverage and applied it to the stories (n=1,169) aired by the main networks in Chile in the 72 hours after an 8.8 magnitude earthquake struck on 27 February 2010. Of the five elements, promoting a sense of safety occurred most often (82.72 per cent), whereas the others were barely present (less than 10 per cent). The study argues that these elements can increase the possibility of framing the news, given that the audience watching can also be affected by a disaster. 相似文献
147.
Manuel Soler Liesbeth de Neve Gianluca Roncalli Elena Macías-Sánchez Juan Diego Ibáñez-Álamo Tomás Pérez-Contreras 《Behavioral ecology and sociobiology》2014,68(2):333-342
The post-fledging period is a critical phase for juvenile survival, and parental care provided during this period is a key component of avian reproductive performance. Very little is known about the relationships between foster parents and fledglings of brood parasites. Here, we present the results of a 5-year study about the relationships between fledglings of the non-evictor brood parasitic great spotted cuckoo (Clamator glandarius) and its magpie (Pica pica) foster parents. Sometimes, great spotted cuckoo and magpie nestlings from the same nest can fledge successfully, but most often parasitic nestlings outcompete host nestlings and only cuckoos leave the nest. We have studied several aspects of cuckoo post-fledging performance (i.e. feeding behaviour, parental defence and fledgling survival) in experimental nests in which only cuckoos or both magpie and cuckoo nestlings survived until leaving the nest. The results indicate that great spotted cuckoo fledglings reared in mixed broods together with magpie nestlings were disadvantaged by magpie adults with respect to feeding patterns. Fledgling cuckoos reared in mixed broods were fed less frequently than those reared in only cuckoo broods, and magpie adults approached less frequently to feed cuckoos from mixed broods than cuckoos from only cuckoo broods. These results imply that the presence of host's own nestlings for comparison may be a crucial clue favouring the evolution of fledgling discrimination; and furthermore, that the risk of discrimination at the fledgling stage probably is an important selection pressure driving the evolution of the arms race between brood parasites and their hosts. 相似文献
148.
María D. Álvarez 《The Environmentalist》2001,21(4):305-315
The forests of Colombia are influenced by the actions of armed groups and, in many cases, their settlers are economically dependent on illicit crops. Up to the present armed conflict has simultaneously discouraged organized exploitation in some frontier areas, and encouraged unsustainable use of natural resources therein. The Colombian government seeks to end the conflict by pursuing peace negotiations, and to eradicate illicit crops. How will these policies affect the forests? The environmental consequences of these policies are not only dependent on the unlikely economic success of alternative development, but on making informed decisions about infrastructure development in affected areas. 相似文献
149.
FERNANDO TOMÁS MAESTRE GIL 《Environmental management》2001,28(2):149-163
Local scale has an important role in environmental management. In Spain, rapid industrialization has occurred in the last
three decades, leading to substantial changes in socioeconomic relations and resulting in significant environmental degradation.
This paper describes the environmental status of the township of Sax (Alicante, in southeast Spain), which has passed from
agriculture to industrial manufacturing in 50 years. The human population has grown exponentially during the second half of
the 20th century, with a 91% increase from 1955 to 1995, coinciding with strong growth in manufacturing (factories increased
fivefold in the period 1955–1976) and important changes in the working population and land use. Illegal rubbish dumps, water
pollution, forest fires, erosion, and degradation of wildlife habitats are the main outcomes of these dramatic socioeconomic
and demographic changes. The administration has focused on the control of water pollution and waste management, while nongovernmental
organizations have concentrated on the prevention of forest fires and the development of environmental education programs.
These measures are insufficient to manage current environmental degradation, and an environmental management plan for the
study area is discussed. Increasing effort in waste management and industrial wastewater control, changes in land-use policy,
and the creation of an advisory committee to increase public participation in decision-making have been identified as environmental
target objectives for the coming years. 相似文献
150.
Juan Francisco Sánchez Pérez Enrique González Ferradás Fernando Díaz Alonso Daniel Palacios García María Victoria Mínguez Cano José Ángel Bautista Cotorruelo 《Process Safety and Environmental Protection》2010,88(2):109-113
In this paper new Probit equations are proposed to estimate damage produced by thermal radiation on humans (for first- and second-degree burns). They are compared to empirical threshold values and also to existing Probit equations. Results obtained are in good agreement with previous empirical experience. They also provide better estimations than existing equations. When an analysis is performed to study the evolution in the percentage of affected people by different degrees of damages, results show that proposed equations produce more consistent results than existing equations. 相似文献