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61.
Ovarian macroscopical analysis, histological validation and field sampling procedures were used to evaluate the variability in reproductive traits of the mole crab Emerita brasiliensis Schmitt, 1935 (Decapoda: Hippidae) in two exposed sandy beaches of Uruguay with contrasting morphodynamics. All developmental stages involved in the complex life cycle exhibited lower abundance, individual size and temporal occurrence in a harsh reflective beach, compared with a more benign dissipative environment. In addition, this population showed more compressed events of the reproductive cycle (e.g oogenesis, encounter of potential mate and female parental care) and recruitment period. However, the beginning of the vitellogenesis, ovary maturity, male sexual differentiation and ending of spermatogenesis occurred at smaller sizes under dissipative conditions. These results disagree with the recent findings of delayed sexual maturity in dissipative beaches. We postulate that, in dissipative conditions, high food availability might allow an overlapping of reproductive and moulting processes, and thus females may reach optimum size and sexual maturity with fewer moults than in reflective beaches. Hence, reproductive responses must be considered not only in relation to environmental harshness, but also in the context of life history traits and their phylogenetic and allometric constraints. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   
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The growing complexity and global nature of wildlife poaching threaten the survival of many species worldwide and are outpacing conservation efforts. Here, we reviewed proximal and distal factors, both social and ecological, driving illegal killing or poaching of large carnivores at sites where it can potentially occur. Through this review, we developed a conceptual social–ecological system framework that ties together many of the factors influencing large carnivore poaching. Unlike most conservation action models, an important attribute of our framework is the integration of multiple factors related to both human motivations and animal vulnerability into feedbacks. We apply our framework to two case studies, tigers in Laos and wolverines in northern Sweden, to demonstrate its utility in disentangling some of the complex features of carnivore poaching that may have hindered effective responses to the current poaching crisis. Our framework offers a common platform to help guide future research on wildlife poaching feedbacks, which has hitherto been lacking, in order to effectively inform policy making and enforcement.  相似文献   
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ABSTRACT: Due to the spread of Islam in the seventh century the number of pilgrims to the City of Makkah increased sharply, resulting in an acute water shortage. To solve this problem, galleries were built to collect water from the upstream of Wadi Naaman and transfer it to Makkah. Expansion of Makkah and the absence of any mapping of the galleries have resulted in the destruction of a part of the galleries. This caused a discontinuity of flow in the galleries and, consequently, the ground water table is rising at a rate of 0.48 m/yr, causing environmental problems. Research was conducted to rehabilitate the destructed part of the galleries, and to find an appropriate use for the ground water. The study found that the quality of the ground water is suitable for landscaping purposes, that is, for the irrigation of trees and ornamental plants.  相似文献   
64.
ABSTRACT: Extensive use is made of on-site wastewater disposal systems of cesspools due to the absence of a sanitary sewerage system in Saudi urban areas. This system has caused the groundwater table to rise to a public nuisance level. A health risk has also evolved. There are several infrastructural, environmental, and social impacts from this, resulting in great financial losses. Examples are: surface water flooding, damage to foundations of buildings and asphalt street pavements, flooded basements and added construction costs required for excavation, dewatering, insulation materials, and special cements. Most of these costs are indirectly being paid by the private and public sectors. This study compares the estimated costs of damage and losses with the estimated costs of building, operating, and maintaining sanitary sewerage systems in the cesspool-served areas. The annual cost of the cesspool system, depending on the severity of the adverse impacts, ranges from 2.2 to 4.4 times the annual cost of the sanitary sewerage system. Remedies for these impacts are very expensive, and delays in the implementation of the sanitary sewerage facility will make the damage recovery more expensive, and in some cases, impossible. Thus, it is recommended that highest priority to be given to the sanitary sewerage systems in Saudi urban areas.  相似文献   
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Environmental Science and Pollution Research - The bioactivity of nanoparticles has engendered a promise in scientific communities for developing novel therapeutic strategies. This study...  相似文献   
67.
Environmental Science and Pollution Research - The Himalayan glaciers provide water to a large population in south Asia for a variety of purposes and ecosystem services. As a result, regional...  相似文献   
68.
The prediction of the potential hazards associated to accidental liquefied natural gas (LNG) spills has motivated a number of different studies including experimental and numerical approaches. Most of these studies focus on dispersion predictions, however there is limited information regarding source term of it: liquid spill and vaporization. There is a need of further improvements on the understanding of these phenomena and the quantification of the most important parameters that can affect them.The vaporization of cryogenic liquids is governed by the heat transfer phenomena including conduction, convection and thermal radiation mechanisms. The present work investigates the contribution of each of these heat transfer modes to the vaporization rate of cryogenic liquid nitrogen (LN2) contained in a Dewar flask using well controlled and instrumented laboratory scale experiments. LN2 vaporization rate was measured with individually controllable contributions from convective (generated by an electric fan) and thermal radiative (generated by light bulb) heat transfer in the presence of a baseline conductive heat transfer rate.In both cases of convection and radiation analysis the experimental study showed that they can play a significant role in the vaporization rate of LN2. It was observed that the radiative heat absorbed by the LN2 during the vaporization experiment represents only 50%–65% of the incident radiation that would reach the LN2 pool surface if no vapour was present. Convective heat transfer generated by the fan was shown to have had the most significant contribution to the total heat transfer. As expected, this contribution was significantly higher than the one from bulb radiation. The experimental data also showed that the liquid level in the Dewar play a key role in the resulting amount of convective heat transfer. This could be attributed to the fact that lower liquid level the side walls of the Dewar were high enough to hold a layer of vapour and limit air motion directly above the liquid surface, thus limiting the heat transfer by convection.  相似文献   
69.
Environmental Science and Pollution Research - Serum total and free calcium reflect the status of the body health and disease. Smoking is risk factor for many diseases as cardiovascular, lung, and...  相似文献   
70.
Environmental Science and Pollution Research - The looming water resources worldwide necessitate the development of water-saving technologies in rice production. An open greenhouse experiment was...  相似文献   
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