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101.
Disasters of physical origin, including earthquakes, floods, landslides, tidal waves, tropical storms, tsunamis, and volcanic eruptions, have affected millions of people globally over the past 100 years. Proportionately, there is far greater likelihood of being affected by such disasters in low‐income countries than in high‐income countries. Furthermore, low‐income countries are in need of international assistance following disasters more often than high‐income countries. The funding of international humanitarian assistance has increased from USD 12.9 billion in 2006 to an estimated USD 16.7 billion in 2010. The majority of this funding is channelled through humanitarian agencies and is supposed to be distributed based on the need of those affected, as assessed using needs assessments. Such needs assessments may be used to inform decisions internally, to influence others, to justify response decisions, and to obtain funding. Little is known about the quality of needs assessments in practical applications. Consequently, this paper reports on and analyses the views of operational decision‐makers in major health‐related humanitarian agencies on needs assessments.  相似文献   
102.
Animals inhabiting hydrothermal vents and cold seeps face conditions that are challenging for survival. In particular, these two habitats are characterized by chronic hypoxia, sometimes reaching complete anoxia. The characteristics of the scaphognathite and gills were studied in four species of shrimp and three species of crabs from hydrothermal vents and cold seeps, in order to highlight potential adaptations that could enhance oxygen acquisition in comparison with shallow-water relatives. All the vent and seep species studied here exhibit significantly larger scaphognathites, likely allowing more water to flow over their gills per stroke of this appendage. This is probably more energetically efficient that prolonged hyperventilation. In contrast to annelids, vent and seep decapods usually do not possess enlarged gills, a phenomenon likely due to the physical limitations imposed by the size of the gill chamber. In the vent shrimp Rimicaris exoculata and the vent crab Bythograea thermydron, however, there is a significantly higher specific gill surface area linked to a higher number of lamellae per gram of gill. Again in contrast to annelids, the diffusion distance through the gills is not strikingly different between the vent shrimp Alvinocaris komaii and the shallow-water species Palaemon spp. This may indicate that the epithelium and cuticle of the decapod gills are already optimized for oxygen uptake and that reducing the thickness of these compartments is not physically possible without affecting the physical integrity of the gills.  相似文献   
103.
Corporate social performance (CSP) is assumed to have a positive impact on macroeconomic sustainability, but empirical evidence of this impact is absent in the literature. The objective of this paper is to investigate the macro impacts of CSP. We first establish a conceptual framework on the relationship between CSP at the individual business level and sustainability at the macro level. Next, we empirically test the relationship between (averaged) CSP scores and greenhouse gas emissions at the macro level for 22 countries during 2004–2011. We use Granger causality tests to check for Granger causality. The estimation results show that CSP reduces greenhouse gas emissions, but the long-term effect is rather modest.  相似文献   
104.
This study tests the applicability of the curve number (CN) method within the Soil and Water Assessment Tool (SWAT) to estimate surface runoff at the watershed scale in tropical regions. To do this, surface runoff simulated using the CN method was compared with observed runoff in numerous rainfall‐runoff events in three small tropical watersheds located in the Upper Blue Nile basin, Ethiopia. The CN method generally performed well in simulating surface runoff in the studied watersheds (Nash‐Sutcliff efficiency [NSE] > 0.7; percent bias [PBIAS] < 32%). Moreover, there was no difference in the performance of the CN method in simulating surface runoff under low and high antecedent rainfall (PBIAS for both antecedent conditions: ~30%; modified NSE: ~0.4). It was also found that the method accurately estimated surface runoff at high rainfall intensity (e.g., PBIAS < 15%); however, at low rainfall intensity, the CN method repeatedly underestimated surface runoff (e.g., PBIAS > 60%). This was possibly due to low infiltrability and valley bottom saturated areas typical of many tropical soils, indicating that there is scope for further improvements in the parameterization/representation of tropical soils in the CN method for runoff estimation, to capture low rainfall‐intensity events. In this study the retention parameter was linked to the soil moisture content, which seems to be an appropriate approach to account for antecedent wetness conditions in the tropics.  相似文献   
105.
Knowledge of how species interactions are influenced by climate warming is paramount to understand current biodiversity changes. We review phenological changes of Swedish butterflies during the latest decades and explore potential climate effects on butterfly–host plant interactions using the Orange tip butterfly Anthocharis cardamines and its host plants as a model system. This butterfly has advanced its appearance dates substantially, and its mean flight date shows a positive correlation with latitude. We show that there is a large latitudinal variation in host use and that butterfly populations select plant individuals based on their flowering phenology. We conclude that A. cardamines is a phenological specialist but a host species generalist. This implies that thermal plasticity for spring development influences host utilization of the butterfly through effects on the phenological matching with its host plants. However, the host utilization strategy of A. cardamines appears to render it resilient to relatively large variation in climate.  相似文献   
106.
Epidemiological data indicate that exposure to diesel exhaust particles (DEPs) from traffic emissions is associated with higher risk of morbidity and mortality related to cardiovascular and pulmonary diseases, accelerated progression of atherosclerotic plaques, and possible lung cancer. While the impact of DEPs from combustion of fossil diesel fuel on human health has been extensively studied, current knowledge of DEPs from combustion of biofuels provides limited and inconsistent information about its mutagenicity and genotoxicity, as well as possible adverse health risks. The objective of the present work was to compare the genotoxicity of DEPs from combustion of two first-generation fuels, 7% fatty acid methyl esters (FAME) (B7) and 20% FAME (B20), and a second-generation 20% FAME/hydrotreated vegetable oil (SHB: synthetic hydrocarbon biofuel) fuel. Our results revealed that particulate engine emissions from each type of biodiesel fuel induced genotoxic effects in BEAS-2B and A549 cells, manifested as the increased levels of single-strand breaks, the increased frequencies of micronuclei, or the deregulated expression of genes involved in DNA damage signaling pathways. We also found that none of the tested DEPs showed the induction of oxidative DNA damage and the gamma-H2AX-detectable double-strand breaks. The most pronounced differences concerning the tested particles were observed for the induction of single-strand breaks, with the greatest genotoxicity being associated with the B7-derived DEPs. The differences in other effects between DEPs from the different biodiesel blend percentage and biodiesel feedstock were also observed, but the magnitude of these variations was limited.  相似文献   
107.
Establishment of plans for environmental planning and management requires that a number of natural and societal factors must be taken into consideration. Insights into the inherent dynamics of nature as well as the role that past human activities have played for establishing the current condition of the landscape and the natural environment in general are essential. Many natural and man-made changes occur over time scales of decades or centuries, and these are difficult to comprehend without a historical perspective. Such a perspective can be obtained using palaeoecological studies, i.e. by geochemical and biological analyses of lake sediment and peat deposits. To illustrate the long-term dynamics of nature and particularly the role of man, we present here five case studies from Sweden concerning pollution, lake acidification, lake eutrophication, biodiversity, and landscape dynamics and conservation – topics of broad interests – and discuss benefits of including a longer time perspective in environmental management.  相似文献   
108.
Linking Theory and Practice for Restoration of Step-Pool Streams   总被引:1,自引:0,他引:1  
Step-pools sequences are increasingly used to restore stream channels. This increase corresponds to significant advances in theory for step-pools in recent years. The need for step-pools in stream restoration arises as urban development encroaches into steep terrain in response to population pressures, as stream channels in lower-gradient areas require stabilization due to hydrological alterations associated with land-use changes, and as step-pools are recognized for their potential to enhance stream habitats. Despite an increasingly voluminous literature and great demand for restoration using step-pool sequences, however, the link between theory and practice is limited. In this article, we present four unique cases of stream restoration using step-pools, including the evolution of the approaches, the project designs, and adjustments in the system following restoration. Baxter Creek in El Cerrito, California demonstrates an early application of artificial step-pools in which natural adjustments occurred toward geomorphic stability and ecological improvement. Restoration of East Alamo Creek in a large residential development near San Ramon, California illustrates an example of step-pools increasingly used in locations where such a channel form would not naturally occur. Construction of a step-pool channel in Karnowsky Creek within the Siuslaw National Forest, Oregon overcame constraints posed by access and the type and availability of materials; the placement of logs allowed natural scouring below steps. Dry Canyon Creek on the property of the Mountains Restoration Trust in Calabasas, California afforded a somewhat experimental approach to designing step-pools, allowing observation and learning in the future. These cases demonstrate how theories and relationships developed for step-pool sequences over the past two decades have been applied in real-world settings. The lessons from these examples enable us to develop considerations useful for deriving an appropriate course of design, approval, and construction of artificial step-pool systems. They also raise additional fundamental questions concerning appropriate strategies for restoration of step-pool streams. Outstanding challenges are highlighted as opportunities for continuing theoretical work.  相似文献   
109.
通过把全面的农田试验和矿质风化释放养分以及微量元素循环具体研究结合起来,用一个系统分析方法来评价农场尺度上的养分和微量元素可持续性.为了比较有机和常规农业管理方式,在瑞典北部的Ojebyn奶牛场进行了一个包括磷、钾和锌在内的农场尺度上的实例研究.通过结合不同的元素平衡法(农场总体尺度、畜舍尺度和农田尺度)以及进一步把这些方法应用到FARMFLOw模型,我们能够把子系统内质量流和库结合起来并建立子系统之间联系,来进行农场尺度上的预测.研究发现农场内部的元素流动大,而且农场有内部源(锌)和损失项(钾).在Ojebyn奶牛场形成并得到验证的方法是很有前途的,认为可以应用到任何农场.  相似文献   
110.
The mechanism by which palatable species take advantage of their similarity in appearance to those that are unpalatable, in order to avoid predation, is called Batesian mimicry. Several arthropods are thought to be Batesian mimics of social insects; however, social insects that are Batesian mimics among themselves are rare. In Malaysia we found a possible Batesian mimic in an arboreal ant species, Camponotus sp., which was exclusively observed on foraging trails of the myrmicine ant Crematogaster inflata. The bright yellow and black colouring pattern, as well as the walking behaviour, were very similar in both species. We observed general interactions between the two species, and tested their palatability and the significance of the remarkably similar visual colour patterns for predator avoidance. Prey offered to C. inflata was also eaten by Camponotus workers in spite of their being attacked by C. inflata, indicating that Camponotus sp. is a commensal of C. inflata. An experiment with chicks as potential predators suggests that Camponotus sp. is palatable whereas C. inflata is unpalatable. After tasting C. inflata, the chicks no longer attacked Camponotus sp., indicating that Camponotus sp. is a Batesian mimic of Crematogaster inflata.  相似文献   
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