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1.
Fire weather indices predict fire extent from meteorological conditions assuming a monotonic function; this approach is frequently used to predict future fire patterns under climate change scenarios using linear extrapolation. However, the relationship between weather and fire extent may potentially depend on the existence of fuel moisture content thresholds above which this relationship changes dramatically, challenging this statistical approach. Here, we combine the continuous and the threshold approaches to analyze satellite-detected fires in Europe during 2001–2010 in relation to meteorological conditions, showing that fire size response to decreasing fuel moisture content follows a ramp function, i.e., with two plateaus separated by a phase of monotonic increase. This study confirms that at continental and high-resolution temporal scales, large fires are very unlikely to occur under moist conditions, but it also reveals that fire size stops to be controlled by fuel moisture content above a given threshold of dryness. Thus, fuel moisture content control only applies when fire is not limited by other factors such as fuel load, as large fires were virtually absent during the considered period in dry regions with less than 500 mm of average annual precipitation, i.e., low-productive areas where fuel amount would be scarce and discontinuous. In regions with sufficient fuel, other factors such as fire suppression or fuel discontinuity can impede large fires even under very dry weather conditions. These findings are relevant under current climatic trends in which the fire season length, in terms of number of days with drought code values above the observed thresholds (break points), is increasing in many parts of the Mediterranean, while it is decreasing in eastern Europe and remains unchanged in central Europe.  相似文献   
2.
OBJECTIVES: The possible connection between diseases among drivers and traffic accidents was examined for traffic safety purposes. METHODS: We studied medical conditions of drivers and passengers in all motor vehicle crashes with fatalities in Finland in 2001 and 2002 by using reports of road accident investigation teams, including autopsy reports. We analyzed a total of 542 crashes with 640 fatalities. Findings were also compared with available epidemiological data in Finland. RESULTS: An insignificant difference in the number of reported diseases was present between the different parties involved in crashes. However, among killed key drivers, so-called A-parties, psychiatric diseases, especially alcoholism, depression, and unspecific mental disorders, were diagnosed more often than in the groups of other drivers or passengers. In addition, A-parties were reported to more frequently suffer from cerebral arteriosclerosis and arterial hypertension. CONCLUSIONS: Drivers' diseases can be a risk factor for traffic accidents. Fitness to drive should therefore be considered in medical practice, particularly in patients with alcoholism and other psychiatric disorders.  相似文献   
3.
Laypeople's acceptance and perception of Carbon Dioxide Capture and Storage (CCS) can have an influence on its political feasibility. It is important, therefore, to study how laypeople perceive CCS and which cognitions they hold with respect to this technique. We conducted in-depth interviews with laypeople (N = 16) to explore their mental concepts of CCS. Little knowledge about CCS was detected among laypeople. We also found that laypeople fear that a deployment of CCS could create incentives that would hinder a sustainable development of the energy economy. A misunderstanding of the concepts of hydro- and geostatic pressure, as well as a lack of knowledge about the physical–chemical properties of carbon dioxide seemed to trigger fundamental rejection of CCS among some laypeople. This qualitative study identifies concepts that underlie CCS perception, and these should be objects of future studies. We provide some suggestions for risk management and communication about CCS.  相似文献   
4.
Models of two-patch predator-prey metacommunities are used to explore how the global predator population changes in response to additional mortality in one of the patches. This could describe the dynamics of a predator in an environment that includes a refuge area where that predator is protected and a spatially distinct ("risky") area where it is harvested. The predator's movement is based on its perceived fitness in the two patches, but the risk from the additional mortality is potentially undetectable; this often occurs when the mortality is from human harvesting or from a novel type of top predator. Increases in undetected mortality in the risky area can produce an abrupt collapse of either the refuge population or of the entire predator population when the mortality rate exceeds a threshold level. This is due to the attraction of the risky patch, which has abundant prey due to its high predator mortality. Extinction of the refuge predator population does not occur when the refuge patch has a higher maximum per capita predator growth rate than the exploited patch because the refuge is then more attractive when the predator is rare. The possibility of abrupt extinction of one or both patches from high densities in response to a small increase in harvest is often associated with alternative states. In such cases, large reductions in mortality may be needed to avoid extinction in a collapsing predator population, or to reestablish an extinct population. Our analysis provides a potential explanation for sudden collapses of harvested populations, and it argues for more consideration of adaptive movement in designing protected areas.  相似文献   
5.
The regional bioeconomy has a high importance for generating socio-economic impacts, especially in sparsely populated resource peripheries. The benefits include increased employment and income and improved security of supply. In this study, the modified regional input?Coutput model is applied for analysing the socio-economic impacts of Suutela wooden village construction in North Karelia, Finland. The main objective of this article is to provide an illustrative example on the regional input?Coutput modelling, applied to the investigation of the socio-economic impacts of a conventional, decentralised bioeconomy. Based on this Finnish case of a wooden village with bioenergy district heating, we demonstrate both the employment and income potentials of a decentralised bioeconomy. The results indicate good socio-economic potential of local wood construction, resulting in about 250 personnel working years and a total economic impact of 43.7 million euros on the regional economy. To maintain the sensitivity of the input?Coutput modelling, it is considered more suitable for overall regional impact estimations, rather than pointing out differences between the subsystems. When modified for research purposes, the regional input?Coutput model is well capable to efficiently describe the socio-economic impacts and providing information for local decision-makers to support new projects of a bioeconomy.  相似文献   
6.
This study addresses the exhaust emissions of CO2, NOx, SOx, CO, and PM2.5 originated from Baltic Sea shipping in 2006–2009. Numerical results have been computed using the Ship Traffic Emissions Assessment Model. This model is based on the messages of the automatic identification system (AIS), which enable the positioning of ships with a high spatial resolution. The NOx emissions in 2009 were approximately 7 % higher than in 2006, despite the economic recession. However, the SOx emissions in 2009 were approximately 14 % lower, when compared to those in 2006, mainly caused by the fuel requirements of the SOx emission control area (SECA) which became effective in May 2006, but affected also by changes in ship activity. Results are presented on the differential geographic distribution of shipping emissions before (Jan–April 2006) and after (Jan–April 2009) the SECA regulations. The predicted NOx emissions in 2009 substantially exceeded the emissions in 2006 along major ship routes and at numerous harbors, mostly due to the continuous increase in the number of small vessels that use AIS transmitters. Although the SOx emissions have been reduced in 2009 in most major ship routes, these have increased in the vicinity of some harbors and on some densely trafficked routes. A seasonal variation of emissions is also presented, as well as the distribution of emissions in terms of vessel flag state, type, and weight.  相似文献   
7.
Vadstein O  Olsen LM  Andersen T 《Ecology》2012,93(8):1795-1801
Classical models of prey-predator interactions assume that per capita prey consumption is dependent on prey density alone and that prey consumption (functional response) and consumer proliferation (numerical response) operate on the same timescales and without time lags. Several modifications have been proposed for resolving this timescale discrepancy, including variants where the functional response depends on both prey and predator densities. A microcosm system with the rotifer Brachionus 'Nevada' feeding on the prasinophyte Tetraselmis sp. showed significant (P < 0.0005) increases in steady-state biomasses of both prey and predators with increasing carrying capacity (represented by total phosphorus of the growth medium), which is inconsistent with predictions based on the traditional prey-only-dependent functional response. We provide data indicating that surfaces where the predator can attach provide a high-quality habitat for rotifers, which can result in a predator-dependent functional response. We also show that partitioning between the attached and free-swimming habitats was fast compared to the timescale of the numerical response. When attached to surfaces, rotifers maximized net energy gain by avoiding the high cost of swimming and by increased food capture due to reduced viscous drag. A mathematical model with prey-dependent functional response and wall-attached and free-swimming fractions of the population describes our data adequately. We discuss the implications of this finding for extrapolating microcosm experiments to systems with other surface-to-volume ratios, and to what extent our findings may apply to other popular model organisms for prey-predator interaction.  相似文献   
8.
Otolith microchemistry is widely used as a tool to track individual migration pathways of diadromous fish under the assumption that the elemental composition of fish otoliths is directly influenced by the physicochemical properties of the surrounding water. Nevertheless, several endogenous factors are reported to affect element incorporation into fish otoliths and might lead to misinterpretations of migration studies. This study experimentally examined the influence of eight different diets on the microchemical composition of European eel (Anguilla anguilla) otoliths using laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS). Seven natural prey types and one artificial diet were fed during 8 weeks in freshwater circuits. Results show for the first time that food has no significant influence on the incorporation of Na, Sr, Ba, Mg, Mn, Cu and Y into European eel otoliths. This indicates that the incorporation of elements usually chosen for migration studies is not affected by diet and that individual feeding behaviour of A. anguilla will not lead to any misinterpretation of migration pathways.  相似文献   
9.
Life cycle assessment-based environmental product declarations (EPDs) require the inclusion of biodiversity impacts across the entire supply chain. The objective of this study is to test the applicability of a Scandinavian biodiversity assessment tool, developed specifically for use with EPD applications, in an African desert environment, linking the industry types power generation and mining. For this purpose, a GIS-based spatial analysis tool—the biotope method—was adapted to a framework approach which allowed the selection of more suitable, site-specific biodiversity indicators. The biotope method provides a step-by-step process of defining system boundaries, mapping biotopes, categorizing biotopes based on site-specific indicators, and evaluating change in biotope status “before” and “after” the impact. The development of site-specific indicators was piloted in this study and determined by the affected ecosystem and the status of knowledge on biodiversity in this geographic area. Thus plants were used as indicators for biodiversity, and red-list status and endemism constituted the prime criteria for conservation value of plants. This in turn represented the key criterion for classifying biotopes. The tested biodiversity assessment tool has potential for application in different environments and operational settings but leaves room for improvement by including secondary impacts in the assessment and using a wider range of taxa for indicators of biodiversity.  相似文献   
10.
This paper presents a change in the Scottish forestry policy from the exogenous to the endogenous development approach, and feasibility of heat entrepreneurship based on locally produced woodfuels in the Highlands of Scotland. The cost structure and heat pricing in the case of an 800 kW solid fuel boiler is presented, and the profitability of local heat entrepreneurship is analysed with scenarios of different investment costs and fuel prices. The results indicate that a district heating (DH) system, using locally produced woodchips, could produce heat at a lower price than single-house heating systems using light fuel oil. The profitability of replacing existing heating units by investing in a new district heating (DH) scheme is very dependent on the available investment support, price level of woodchips and substituted light fuel oil, and the amount of sold energy. In the case of an 800 kW DH scheme, and woodchip prices of 14 and 22 €/MWh, investments should remain under break-even points of 280 and 420 €/kW of heating power (230,000–335,000€).  相似文献   
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