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231.
Tourism is a financing mechanism considered by many donor-funded marine conservation initiatives. Here we assess the potential role of visitor entry fees, in generating the necessary revenue to manage a marine protected area (MPA), established through a Global Environmental Facility Grant, in a temperate region of Chile. We assess tourists’ willingness to pay (WTP) for an entry fee associated to management and protection of the MPA. Results show 97 % of respondents were willing to pay an entrance fee. WTP predictors included the type of tourist, tourists’ sensitivity to crowding, education, and understanding of ecological benefits of the MPA. Nature-based tourists state median WTP values of US$ 4.38 and Sun-sea-sand tourists US$ 3.77. Overall, entry fees could account for 10–13 % of MPA running costs. In Chile, where funding for conservation runs among the weakest in the world, visitor entry fees are no panacea in the short term and other mechanisms, including direct state/government support, should be considered.  相似文献   
232.
Electrofishing is considered a reliable tool to assess the assemblages and biodiversity of fish in wadeable streams. The most widely used electrofishing techniques (point [P], single-pass [S-P], and multiple-pass [M-P]) vary as to the effort needed for sample collection, and this may potentially influence the degree of accuracy. Moreover, little is known about the comparability of the methods and their specific performance in streams with different fish assemblages. The aim of this investigation was to validate (using M-P sampling as reference) the use of P and S-P electrofishing techniques to accurately assess the richness, density and size distribution of fishes in small streams at both regional and global scale independently of fish assemblages and geographical region. We sampled 50-m-long reaches in a total of 33 lowland stream reaches that were located in different climatic and biogeographical regions (Uruguay and Denmark) and hosted different fish assemblages. Subtropical fish communities exhibited higher richness (Uy: 12–32, Dk: 1–9) and densities (Uy: 1.3–5.2, DK: 0.1–4.9 in. m?2) than temperate streams. We applied both "global models" using the entire database (33 sites) and "local models" including the same number of sites but using the climatic region as a model variable. Regression analyses revealed that the P, S-P and M-P methods all provided an adequate picture of the species composition and size distribution, and transfer equations for comparison between methods are thus not required. Conversely, richness was better predicted by S-P and by P techniques for regional and global models, respectively. Transfer equations obtained for abundance revealed that the P and S-P models can accurately transform catch data into M-P estimations. The transfer equations provided here may have great relevance as they allow relatively reliable comparisons to be made between data obtained by different techniques. We also show that less intensive sampling techniques may be equally useful for monitoring purposes as those requiring more intensive efforts (and costs). We encourage validation of our developed transfer equations on data from other regions of the world.  相似文献   
233.
Grapevines grown on acid soils with low fertility in southern Brazil are treated with intense foliar applications of copper (Cu) fungicides, resulting in an increased level of Cu in the soil and increased toxicity. The present study evaluated the accumulation and bioavailability of Cu, and soils with varying levels of Cu from the main producing regions of southern Brazil were collected. The forms of Cu present in the soil were assessed using chemical extractants; additionally, oat cultivation was performed, reflecting the use of the plant as an indicator of Cu bioavailability. Cu accumulated in the topsoil, mainly in bioavailable forms, and there was also an increase of Cu up to a depth of 0.4 m. Cu was primarily found in the mineral fraction, with apparent saturation of the soil organic matter functional groups. Inceptisol and Alfisol soils with a long history of cupric fungicide application were found to have levels of Cu toxic to oat plants. Furthermore, accumulated copper in Alfisol soil from the Campanha Gaúcha region of the state of Rio Grande do Sul had higher bioavailability compared to Cu accumulated in Inceptisol soil from the Serra Gaúcha region. In addition, the copper concentration in roots was found to serve as an indicator of Cu bioavailability in soil, but not of copper phytotoxicity in plants.  相似文献   
234.
Human activities are accelerating global biodiversity change and have resulted in severely threatened ecosystem services. A large proportion of terrestrial biodiversity is harbored by soil, but soil biodiversity has been omitted from many global biodiversity assessments and conservation actions, and understanding of global patterns of soil biodiversity remains limited. In particular, the extent to which hotspots and coldspots of aboveground and soil biodiversity overlap is not clear. We examined global patterns of these overlaps by mapping indices of aboveground (mammals, birds, amphibians, vascular plants) and soil (bacteria, fungi, macrofauna) biodiversity that we created using previously published data on species richness. Areas of mismatch between aboveground and soil biodiversity covered 27% of Earth's terrestrial surface. The temperate broadleaf and mixed forests biome had the highest proportion of grid cells with high aboveground biodiversity but low soil biodiversity, whereas the boreal and tundra biomes had intermediate soil biodiversity but low aboveground biodiversity. While more data on soil biodiversity are needed, both to cover geographic gaps and to include additional taxa, our results suggest that protecting aboveground biodiversity may not sufficiently reduce threats to soil biodiversity. Given the functional importance of soil biodiversity and the role of soils in human well-being, soil biodiversity should be considered further in policy agendas and conservation actions by adapting management practices to sustain soil biodiversity and considering soil biodiversity when designing protected areas.  相似文献   
235.
Introduction. Wheelchair configuration is an important factor influencing the ergonomics of the user–device interface and, from a biomechanical point of view, small changes in chair setup may have a positive influence on the demand on the upper limbs during manual propulsion. This study aimed to investigate the influence of the position of the rear wheels’ axle and the use of accessories on the activity of upper limb muscles during manual wheelchair propulsion. Methods. Electromyography signals of the biceps, triceps, anterior deltoids and pectoralis major were collected for 11 able-bodied subjects in a wheelchair propulsion protocol with four different wheelchair configurations (differing in axle position and the use of accessories) on a straightforward sprint and a slalom course. Results. With accessories, moving the axle forward led to a decrease in the activity of all muscles in both the straightforward sprint (significant differences in triceps, anterior deltoids and biceps) and the slalom course (significant difference in anterior deltoids and biceps). However, when propelling the chair without accessories, no difference was found related to axle position. Conclusion. Changes in wheelchair configuration can influence the ergonomics of manual wheelchair propulsion. Reducing the biomechanical loads may benefit users’ mobility, independence and social participation.  相似文献   
236.
Objective: To determine whether the standard Spanish driving test (ASDE test) was able to identify patients with Parkinson's disease (PD) at risk of unsafe driving and to examine the relationship between the ASDE test and the Useful Field of View (UFOV) as well as with a battery of neuropsychological tests in drivers with PD.

Methods: Thirty-seven patients with PD and 33 controls matched by age and education level were included in an observational study. All participants were active drivers and patients with PD underwent study procedures after taking the medication in the “on” period. Subjects with a Mini-Mental State Examination (MMSE) score ≤ 24 were excluded. Neuropsychological tests (Repeatable Battery for Neuropsychological Status [RBANS], Trail Making Test [TMT-A and -B], and Block Design test), driving performance tests (ASDE Driver Test and UFOV), and daytime sleepiness (Epworth Sleepiness Scale) were assessed.

Results: The PD group performed significantly worse than healthy controls in the ASDE Motor Coordination tests. No significant differences were observed in anticipation speed, multiple reaction time, concentrated attention, and resistance to monotony. All participants successfully completed the UFOV tests. Statistically significant differences between patients with PD and controls were found in processing speed (UFOV1; P =.03) and more patients with PD were found in the categories of higher driving risk levels (P =.03). In addition, patients with PD showed worse scores than healthy controls in visuospatial capacities (Line Orientation), psychomotor speed (Coding and TMT-A), memory (List Recognition, Story Recall), and executive function (TMT-B). The driving tests (ASDE and UFOV) showed a low sensitivity and a high specificity but a higher percentage of patients in the PD group failed in multiple reaction time, concentrated attention, and resistance to monotony. In addition, 18.9% of patients with PD showed a cutoff of 4 for UFOV risk. In the discriminant analysis, Line Orientation (visuospatial/constructive domain) and Figure Recall (delayed memory) were found to be statistically significant with a rate of correct classification of unsafe drivers with PD of 78.2%. In addition, normal results on the Line Orientation item were associated with a 1.5 times higher probability of non-risky driving in the multivariate analysis.

Conclusions: At early stages of the disease, about 19% of patients with PD showed difficulties that may affect their driving capabilities. Line Orientation and Figure Recall are useful to alert clinicians to the risk of unsafe driving. For this reason, patients with PD should be evaluated for driving abilities more regularly to determine the extent of deficits that may influence driving performance.  相似文献   

237.
Nucella lapillus (L.) is a marine gastropod mollusc widely used as a bioindicator of TBT pollution in the North Atlantic coastlines. The species reproductive cycle and the male penis length seasonal/spatial variation were studied at a single site at Aveiro seashore (NW Portugal) between December 2005 and June 2007. The main objective of this work is to assess if the "Relative Penis Size Index" (RPSI)--an important imposex assessment index--varies seasonally and spatially in the same sampling site and how this can affect results obtained in imposex monitoring programmes. Animals able to reproduce were found every month but a seasonal pattern in N. lapillus reproductive cycle was evident. Female gametogenic maturation varied seasonally and a decrease in capsule gland volume and condition factor occurred in late summer/early autumn. The gametogenesis in males did not show a significant seasonal variation as in females but the condition factor, penis length, amount of sperm and prostate volume also diminished in late summer/early autumn. On the other hand, males that were close to egg capsules clusters had larger penises than those far away from clusters. The temporal and spatial male penis length variation introduces a bias on imposex assessment results when using RPSI and the magnitude of the error involved is evaluated for different TBT pollution levels scenarios. We consider that RPSI provides interesting and complementary information that should not be excluded from monitoring programmes, but temporal or spatial comparisons of imposex should be based on other more reliable imposex indices like the VDSI.  相似文献   
238.
本文描述了南美大陆南部陆地和东南沿海地区环境特性及水生栖息地和群落的现状(GIWA巴塔哥尼亚大陆架亚区),结果来自一项GIWA项目框架任务所完成的一份全面评估,绝大部分依据的是公开发表的数据.分析主要集中在跨边界水资源目前的情况和人类活动带来的影响.内陆水体的栖息地和群落变化主要是由为发电和其他用途而建的水坝和水库引起的.从活水环境到净水环境影响了生境,造成了生物群落的改变.在拉普拉塔(La Plata)河流域,外来入侵物种使本地物种消失.过度捕捞和污染影响了生物多样性,造成了海洋栖息地质量下降.本篇文章讨论了相关的原因,讨论了布宜诺斯艾利斯省和渔业资源由两国共享的阿根廷-乌拉圭公共渔业区对沿海生态环境的政策选择.  相似文献   
239.
We applied two methods to assess vulnerability to climate change in Mexico’s agricultural sector. The first one was a principal component analysis (PCA) that weighted each variable separately. For the second one, we integrated the variables in a linear array in which all variables were weighted equally, and then, we used the arithmetic sum of the sub-indices of exposure and sensitivity minus the adaptive capacity to obtain the vulnerability index. We discuss the similarities and differences between two methods with respect to municipal-level maps as the outputs. The application of the method for the agricultural sector in Mexico gave us the spatial distribution of the high- and very-high vulnerability categories, which we propose as a tool for policy. The methods agreed that the very-high vulnerability category is present in 39 municipalities. Also we found that 16 % of the total population in the country is located in high-exposure areas. In addition, 41 % lives in municipalities identified as highly-sensitive. In terms of adaptive capacity, 20 % of the population lives in 1273 municipalities with low-adaptive capacity. Finally, we discuss the need for information regarding vulnerability at the national level to guide policies aimed at reducing exposure and sensitivity and increasing adaptive capacity.  相似文献   
240.
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