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41.
This article summarises the results from four studies on the potential of bioenergy, and one study on the economic feasibility of distributed renewable energy production, in Ostrobothnia, Finland. The scope of the studies was to explore the degree of energy self-sufficiency that could be achieved, and the economic implications and benefits.The results suggest that a great majority of rural areas have the potential for being self-sufficient in their energy production through bioenergy alone, but other renewable energy sources (RES), including for example wind and solar power, will make an even greater contribution in the future. This applies to areas especially outside the largest population centres and most energy intensive industries. Indeed, in peripheral regions the renewable energy potential far exceeds the energy demand, and the spatial coverage of energy self-sufficiency is huge. Other European and global studies also show tremendous RES potential.The economics of small scale power generation units, here represented by biogas plants, are already feasible, despite the technology still being at an early developmental phase. Diffusion of these technologies depends on a number of factors, but single and separate units are emerging all the time. The adoption of RES based energy management systems will however be a long social process.The results give rise to an expectation for more RES based energy generation in Ostrobothnia and Finland and even in Europe and globally. In a time frame of 20–30 years, this development may result in structural changes across the whole energy sector. This comprehensive movement can only be understood and supported by multi- and cross-scientific approaches, and it will in future be a challenge for forthcoming research.  相似文献   
42.
Patchiness is a typical property of water quality in lakes. However, in conventional water quality monitoring, patchiness is usually too expensive to take into account, due to the high number of required samples. This study examines a feasible methodology developed for estimating the representativeness of discrete chlorophyll a measurements. Four spatially extensive data sets were collected from the Enonselkä basin of Lake Vesijärvi in Southern Finland, using a flow trough system with a fluorometer in a moving boat. Data sets were used to estimate (1) the spatial representativeness of discrete sampling; (2) the effect of varying sample size on the detected mean chlorophyll a concentration and on the observed proportion of variance. Spatial representativeness was assessed using semivariogram analysis. Results indicate that the spatial representativeness of discrete sampling can remain undesirably low. Furthermore, in monitoring programs involving just one or only a few samples, there is a significant risk of obtaining a false estimate for the mean value and variance of chlorophyll a concentration over the whole monitoring area.  相似文献   
43.
44.
A simple procedure for correcting loading effects of aethalometer data   总被引:1,自引:0,他引:1  
A simple method for correcting for the loading effects of aethalometer data is presented. The formula BC(CORRECTED) = (1 + k x ATN) x BC(NONCORRECTED), where ATN is the attenuation and BC is black carbon, was used for correcting aethalometer data obtained from measurements at three different sites: a subway station in Helsinki, an urban background measurement station in Helsinki, and a rural station in Hyyti?l? in central Finland. The BC data were compared with simultaneously measured aerosol volume concentrations (V). After the correction algorithm, the BC-to-V ratio remained relatively stable between consequent filter spots, which can be regarded as indirect evidence that the correction algorithm works. The k value calculated from the outdoor sites had a clear seasonal cycle that could be explained by darker aerosol in winter than in summer. When the contribution of BC to the total aerosol volume was high, the k factor was high and vice versa. In winter, the k values at all wavelengths were very close to that obtained from the subway station data. In summer, the k value was wavelength dependent and often negative. When the k value is negative, the noncorrected BC concentrations overestimated the true concentrations.  相似文献   
45.
Eutrophication of the Baltic Sea has potentially increased the frequency and magnitude of cyanobacteria blooms. Eutrophication leads to increased sedimentation of organic material, increasing the extent of anoxic bottoms and subsequently increasing the internal phosphorus loading. In addition, the hypoxic water volume displays a negative relationship with the total dissolved inorganic nitrogen pool, suggesting greater overall nitrogen removal with increased hypoxia. Enhanced internal loading of phosphorus and the removal of dissolved inorganic nitrogen leads to lower nitrogen to phosphorus ratios, which are one of the main factors promoting nitrogenfixing cyanobacteria blooms. Because cyanobacteria blooms in the open waters of the Baltic Sea seem to be strongly regulated by internal processes, the effects of external nutrient reductions are scale-dependent. During longer time scales, reductions in external phosphorus load may reduce cyanobacteria blooms; however, on shorter time scales the internal phosphorus loading can counteract external phosphorus reductions. The coupled processes inducing internal loading, nitrogen removal, and the prevalence of nitrogen-fixing cyanobacteria can qualitatively be described as a potentially self-sustaining "vicious circle." To effectively reduce cyanobacteria blooms and overall signs of eutrophication, reductions in both nitrogen and phosphorus external loads appear essential.  相似文献   
46.
Objective: The purpose of this study was to explore the relationship between annual alcohol consumption per capita/alcohol price index and the number of alcohol-related fatal motor vehicle accidents (AFMVAs). We were particularly interested in whether a tax reduction in 2004 increased the number of alcohol-related accidents.

Method: The data consisted of all fatal motor vehicle accidents (FMVAs) during the years 2000–2016 obtained from a database maintained by the Finnish Crash Data Institute (OTI). The data included all fatally injured drivers. We compared the OTI data to official statistics on annual alcohol consumption and the alcohol price index.

Results: There were 3,447 fatally injured drivers, of which 25% (n = 869) were intoxicated (blood alcohol concentration [BAC] ≥ 0.05%). After the reduction of the alcohol tax in 2004, the alcohol consumption rose 12.4% from 2003 to 2005 and AFMVAs rose 38%. There was a strong correlation (r = 0.7000, P < .018) between the recorded consumption of alcohol and the number of AFMVAs. There was a strong negative correlation between AFMVAs and the combined (retail + restaurant sales) alcohol price index (r = ?0.7863, P = .0005). A linear mixed-effects model showed that a 1-L increase in total alcohol consumption per capita per year increases AFMVAs by 10.6 and a one-unit increase in the price index decreases AFMVAs by 1.8 per year.

Conclusions: The correlation between alcohol consumption and alcohol-related crashes should be considered when making political decisions regarding alcohol price and availability. Any further liberalization of the alcohol policy would likely lead to an increase in alcohol-related fatal motor vehicle accidents. Similar consequences are likely to occur with drugs. Alcohol price policy is an effective way to improve road safety, but other measures taken to prevent FMVAs also seem to reduce the prevalence of AFMVAs.  相似文献   
47.
Conditional mating strategies enable individuals to modulate their mating behaviour depending on ‘individual status’ to maximise fitness. Theory predicts that variation in individual quality can lead to differences in mating preferences. However, empirical evidence is scarce particular in terms of variation in male and female strategies. Here, we experimentally investigated quality-dependent variation in mating preferences concerning reliable quality indicators in Pelvicachromis taeniatus, a colourful cichlid fish with mutual mate choice and ornamentation. Males as well as females were artificially manipulated in phenotypic quality by different feeding regimes. Ornamentation was connected to individual quality in both sexes. Males and females showed conditional mating strategies in different directions. Males showed prudent choice by preferring females of similar quality. In contrast to males, low-quality females preferred highly ornamented males, whereas high-quality females showed neither preferences for high- nor for low-quality males. The results suggest that individuals aim for specific benefits depending on individual quality. Furthermore, the conflicting conditional mating preferences of males and females might lead to sexual conflict, implicating a highly dynamical mating system that evolves even in absence of environmental changes.  相似文献   
48.
An axis is an undirected line where there is no reason to distinguish one end of the line from the other. Phenomena in nature that can be described as axial data are numerous. In this paper a method of trigonometric moments for the axial normal or axial von Mises distribution as an alternative to the method by Arnold and SenGupta (Environ Ecol Stat 13:271–285, 2006) is discussed. Sine-skewed axial Jones–Pewsey, von Mises and wrapped Cauchy distributions are introduced as special cases of a more general construction of skew axial distributions. As an example the methods are applied to a data set which consists of the orientations of logs on the floor of a primeval spruce forest.  相似文献   
49.
The zonation of different Salicornia species within saltmarshes has been described controversially in prior publications. The aim of this study is to detect substantial relations between pedological conditions and the distribution of different Salicornia species (Salicornia stricta Dumort. 1868, Salicornia europaea L. 1753, and Salicornia procumbens Sm 1813). 37 sites were investigated regarding vegetation pattern, soil morphology and physicochemical and chemical soil properties. A multivariate approach indicate a clear differentiation of the sites dominated by different Salicornia species in respect to sand content, redox potential and water content. However, results of a detailed statistical assessment indicate that redox potential and salinity are the most relevant parameters. Salicornia stricta sites are characterized by a variety of grain sizes, reduced conditions in the rhizosphere, highest water contents (median: 71.5 Vol-%) and lowest Eh values (median: ?19.0 mV), indicating the best adaptation to anaerobic soil conditions. Salicornia procumbens occurs on aerated soils (median Eh: 455.6 mV) with high sand contents independent to position relative to mean high tide level. Exhibiting the lowest (11.5‰) and highest soil salinities (41.7‰), even developing in salt pans (136‰), Salicornia europaea feature a great ecological amplitude regarding temporal variations of salinity. These findings underline the ecotypic and phenotypic plasticity of Salicornia species and offer a promising approach for further experimental settings focussing on phenotypic adaptions and ecological amplitudes of Salicornia taxa and ecotypes.  相似文献   
50.
Microbial growth in buildings may evoke respiratory and other symptoms in the occupants and promote decay of construction materials. The decay in wood is usually caused by dry-rot fungus, leading to the decomposition of cellulose and lignin. There are also some mold fungi and bacteria that can use wood as a nutrient. In this study, two trained dogs were used to detect microbial growth present in buildings. The rot fungi Serpula lacrymans, Coniophora puteana and Antrodia sinuosa were used in the training. In addition to decay samples, pieces of healthy birch, pine and imbued wood were used as controls. Another experiment was made using bacteria (Streptomyces sp.). In these experiments, a total of 100 decay, 75 control and 25 bacteria samples were used. The dogs detected 75% of the decay and 60% of the bacteria samples. Some (0-24%) control samples were also expressed as positive. Since the dogs identified also the bacteria samples without any specific training, a new test with some mold strains (Cladosporium, Botrytis, Trichoderma, Penicillium, Aspergillus) was carried out. The dogs found all the decay, mold and bacteria samples but only one sample of healthy wood. The use of dogs to detect mold or decay damage appears to have high specificity and high positive predictive value, but low sensitivity.  相似文献   
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