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41.
This paper describes the results of a study aimed at developing and validating a prediction model to assess the annoyance conditions at the operator station of compact loaders by using noise signal objective parameters only. For this purpose, binaural measurements were carried out on 41 compact loaders, both in stationary and real working conditions. The 62 binaural noise recordings were objectively analysed in terms of acoustic and psychoacoustic parameters and then divided into 9 groups and used in specific jury tests to obtain the subjective annoyance scores. Finally, multiple regression technique was applied to the first 6 groups of noise stimuli to develop the model while the remaining groups were used to validate it.  相似文献   
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Policies aiming at improving biodiversity often consist of costly agri-environmental schemes, i.e. subsidized grazing or mowing of semi-natural areas. However, these practices have widely been found to be insufficient to mitigate biodiversity loss. Rewilding, i.e. restoring natural processes in self-sustaining biodiverse ecosystems, has been proposed as an alternative and is hypothesized to be a more cost-efficient approach to promote biodiversity conservation. Rewilding requires the availability of large natural areas which are not allocated for farming, forestry, and infrastructure to avoid potential conflicts over the use of the area. We perform an ex-ante private cost–benefit analysis of the establishment of four large nature reserves for rewilding in Denmark. We analyse the economic effects of changing from summer grazing in nature areas in combination with cultivated fields and forestry to the establishment of nature reserves in four case areas. We consider two scenarios involving conversion of agriculture and forestry areas into natural areas in combination with either extensive year-round cattle grazing or rewilding with wild large herbivores. In two case areas, it appears possible to establish large nature areas without incurring extra costs. Additionally, rewilding further reduces costs compared to year-round cattle grazing. Two opposing effects were dominant: increased economic rent occurred from the shift from summer grazing to year-round grazing or rewilding, while cessation of agriculture and forestry caused opportunity costs.  相似文献   
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- DOI: http://dx.doi.org/10.1065/espr2006.01.007 Goal, Scope and Background Amu Darya river, one of the main water resources of Uzbekistan, shows a relevant longitudinal enrichment of soluble contents which strongly limits the human uses of its waters. Because of the low natural run-off processes, salts and pollutants are mainly driven to the river by the return waters used for washing and irrigating the surrounding lands. The influence of return waters on stream quality is dramatically relevant in the lower reaches of the river where almost all the flowing waters have been previously used for the agriculture practises. To provide analytical evidence on the potential effects of return waters on the quality of the Amu Darya river, the paper reports and comments data on salinity and metals contents of the waters flowing in the artificial channel network of Bukhara and in the Amu Darya river, from Bukhara up to the dam forming the Tuyamuyn Hydro Complex (THC). Methods A total of 15 sampling sites were selected for the analytical survey: Two sites were located on the Amu Darya river downstream from the inflow of the return waters from Bukhara, two in the river entering in the THC, and three downstream from the dam forming the reservoir complex. The waters entering and leaving the Bukhara agricultural area were sampled in two main collectors, while the waters flowing in the channel system were sampled in six distinct collectors. The following parameters were considered in the survey: pH, Oxygen, Hardness, Salinity, Conductivity, P-PO4 3–, P tot, N tot, N-NO3 2–, N-NO2 –, COD, Ca2+, Mg2+, Fe, Mn, Zn, Cr, Cu, Ni, Cd, Pb. Results and Discussion Salt concentrations below 1000 mg/l were measured in the Amu Darya waters upstream to Bukhara. In the drainage system, salinity exceeds the palatability limit and reaches the maximum peak of 3200 mg/l in the outflow collector. Due to dilution effects, salinity returns to lower values (400–700 mg/l) along the Amu Darya river downstream from Bukhara; calcium and magnesium resulted the major constituents of the overall salinity. No serious metal contaminations were detected in the waters entering and leaving the examined channel system. Differently, the Amu Darya waters upstream to the THC showed a relevant metal contamination, with Cr, Ni, Fe concentrations exceeding the limits for human consumption. In the downstream sites, located in the Tuyamuyn Hydro Complex and in the Amu Darya river flowing out from this reservoir, excluding Fe, all the examined metals showed lover concentrations and values below the normative limits. Conclusion The direct human consumption of the lower Amu Darya waters is strongly limited by salinity and by metal contamination. Although the salinity of the return waters from the Bukhara drainage system results in above normal limits, no corresponding increases were measured in the Amu Darya river downstream from the return water inflow at the time of the survey. As for the metal contamination of the Amu Darya river, the survey revealed the presence of relevant sources of metal contamination downstream from Bukhara external to the agricultural drainage system. This contamination resulted in reduced sedimentation processes taking place in the limnetic zones of the Amu Darya river upstream to the dam forming the Tuyamuyn Hydro Complex. Recommendation and Outlook To fully understand the longitudinal increase of Amu Darya salinity, an evaluation of the cumulative effects of the loads from the main agricultural areas is required, also by using mass-balance models. As for the metals, an investigation should be addressed to identify the anthropogenic sources of contaminations present in the lower Amu Darya region and the metal loads should be diverted.  相似文献   
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In recent years, the study of polarisation vision in animals has seen numerous breakthroughs, not just in terms of what is known about the function of this sensory ability, but also in the experimental methods by which polarisation can be controlled, presented and measured. Once thought to be limited to only a few animal species, polarisation sensitivity is now known to be widespread across many taxonomic groups, and advances in experimental techniques are, in part, responsible for these discoveries. Nevertheless, its study remains challenging, perhaps because of our own poor sensitivity to the polarisation of light, but equally as a result of the slow spread of new practices and methodological innovations within the field. In this review, we introduce the most important steps in designing and calibrating polarised stimuli, within the broader context of areas of current research and the applications of new techniques to key questions. Our aim is to provide a constructive guide to help researchers, particularly those with no background in the physics of polarisation, to design robust experiments that are free from confounding factors.  相似文献   
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ABSTRACT

Aurelia is a jellyfish genus common in coastal and estuarine habitats, that are typically affected by human pressures such as heavy metals contamination. Mercury is one of the most dangerous due to its high toxicity, persistence and bioaccumulation. In this paper, we tested for the first time the independent and combined effects of a level of mercury allowable by European regulation in force and hyposalinity on the asexual reproduction of Aurelia sp. polyps, mirroring a realistic scenario. Both mercury (0.07?µg/L, Maximum Allowable Concentration) and salinity (18 and 23 PSU) and the combination of the two factors stimulated the asexual reproduction increasing the number of polyps and buds during the 41 days of experiments. The increment of the asexual reproduction and the absence of suffering and mortality suggest that levels of mercury below the concentration fixed by the law and hyposalinity conditions could promote jellyfish proliferations, according to the hormesis hypothesis.  相似文献   
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We present a detailed tree species inventory covering Europe, parts of Africa and parts of Asia. The inventory contains 39 groups of species that are important for biogenic VOCs or pollen emission calculations. For example: oak (Quercus), poplar (Populus), pines (Pinus), spruce (Picea), birch (Betula) and alder (Alnus). The inventory is based on national forest inventories and national statistics and gives tree species distribution in percentage within broadleaved as well as conifer forests. The inventory includes data from 799 regions and is redistributed into the 50 km × 50 km EMEP grid. The inventory is therefore prepared for easy implementation into atmospheric transport models by providing an extension to already applied land use data such as the Corine Land Cover (CLC2000) or Global Land Cover (GLC2000). The gridded version of the data set will be available on the webpage http://www.dmu.dk/International/Air/Models/Background/Trees/.  相似文献   
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Stored-product moths cause large economic damage in food processing industries and storage facilities. Control of indoor pests is currently dealt with locally, and control strategies seldom include different mills or cooperative industries in joint efforts to reduce infestations. In colder climates where conditions hinder flight dispersal of stored-product moths, we hypothesize that human transport between mills will facilitate dispersal. Albeit considered intuitive, this hypothesis has so far never been tested. Male moths from three mills (populations) in southern Sweden and Denmark were collected and by using amplified fragment length polymorphism (AFLP) pair-wise F(st) values were calculated. Cluster (population) origins of the genotypes were computed by using a model-based method, structure. The results suggest that known transportation of flour between two mills generate genetically more similar populations of the economically important stored-product moth, Ephestia kuehniella (Zell.) (Lepidoptera; Pyralidae), compared to the third mill, with another distribution area, but situated geographically in between the other mills. The structure model placed the sampled genotypes to belong to either two or five original populations, with a higher probability of two original populations. The third mill was consistently different from the other two mills independent of the models' calculated number of populations. Although the study was restricted to three mills and one transportation route, it highlights the possibility that transportation of food products promotes genetic mixing (i.e. dispersal) of insect pest populations. Including cooperating mills in control (or monitor) strategy schemes against stored-product pest insects would therefore be a more effective action, rather than to treat each mill separately.  相似文献   
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