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21.
An important alternative for sustainable use of tucunaré stocks and improvement in fishermen welfare in Balbina reservoir, Central Amazon, would be to train commercial fisherman to also become tourist guides for sport fishing. In this study, we modeled fishermen response to this question, in order to evaluate the acceptance of such an idea. Thus, we surveyed 47 fishermen, who currently comprise approximately 75% of the total fishermen population. This survey was implemented during December of 2001 and January of 2002. We used a probity analysis to run two models. The first model includes the variables: family size, school level, fishing time, residence time and boat ownership. On the other hand, the second model includes the number of children under and above eight years old but not the family size. Both models are significant and the most relevant variables are: fishing time (years of participation of fisherman is in the activity) and residence time (length of residency of particular fishermen live at the village nearby the reservoir).  相似文献   
22.
Spermophilus townsendii ) prey. These changes could occur directly or as a result of changes in the vegetation available as food and cover for the ground squirrels. We assessed the effects of long-term tracking by armored vehicles by comparing 9-ha areas in sagebrush (Artemisia tridentata) -dominated shrubsteppe and bluegrass (Poa secunda) -dominated grasslands subjected to low-intensity tracking for ∼50 years with others that had not been tracked. We did not detect any effect on ground squirrel population dynamics associated with long-term tracking. Although densities of adults and juveniles tended to be higher in the areas exposed to such tracking, we attribute this difference to other factors that varied spatially. To determine short-term (two-year) effects, we experimentally tracked two sagebrush and two grassland sites with an M-1 tank after animals had begun their inactive season. In the following two active seasons we monitored squirrel demography and behavior and vegetative characteristics on the experimentally tracked sites and compared the results with control sites. Although we experimentally tracked ∼33% of the surface of each of four sites where ground squirrel densities were assessed, the tracking had a detectable effect only on some herbaceous perennials and did not influence ground squirrel densities or behavior significantly during the subsequent two active seasons. We conclude that tracking after the start of the inactive season is likely to influence ground squirrel demography or behavior only if vegetation cover is substantially changed by decreasing coverage of preferred food plants or increasing the coverage of annual grasses and forbs that are succulent for only a short time each year.  相似文献   
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In this paper, the movement behavior of Daphnia magna was studied as a bio-indicator of organophosphorous pesticide (OP) contamination, using an on-line bio-monitoring method, the Multispecies Freshwater Biomonitor. A static test of acute toxicity test revealed the 24-h and 48-h LC(50) values (95% confidence limit) for Daphnia magna to be respectively 0.45 microg/l and 0.21 microg/l for dipterex 3.80 microg/l and 0.90 microg/l for malathion, and 1.25 microg/l and 0.38 microg/l for parathion. The behavior strength of Daphnia magna was a sensitive indicator of sublethal OP stress and resulted in significant concentration-response relationships for the three OPs. Increasing OP concentration will result in more intensive behavioral responses of Daphnia magna and shorter response time, which could be described by the Stepwise Stress Model (SSM). Therefore movement behavior can be effectively applied in early warning of environment quality by on-line bio-monitoring. The intensive changes in behavior strength of Daphnia magna over a short time follow the SSM concept and can be used as an indicator of early stress response to OP accidental contamination.  相似文献   
25.
Zhang G  Chen L  Chen J  Ren Z  Wang Z  Chon TS 《Chemosphere》2012,87(7):734-741
The Stepwise Behavioral Response Model (SBRM), which is a conceptual model, postulated that an organism displays a time-dependent sequence of compensatory Stepwise Behavioral Response (SBR) during exposure to pollutants above their respective thresholds of resistance. In order to prove the model, in this study, the behavioral responses (BRs) of medaka (Oryzias latipes) in the exposure of Arprocarb (A), Carbofuran (C) and Methomyl (M) were analyzed in an online monitoring system (OMS). The Self-Organizing Map (SOM) was utilized for patterning the obtained behavioral data in 0.1 TU (Toxic Unit), 1 TU, 2 TU, 5 TU, 10 TU and 20 TU treatments with control. Some differences among different Carbamate Pesticides (CPs) were observed in different concentrations and the profiles of behavior strength (BS) on SOM were variable depending upon levels of concentration. The time of the first significant decrease of BS (SD-BS) was in inverse ratio to the CP concentrations. Movement behavior showed by medaka mainly included No effect, Stimulation, Acclimation, Adjustment (Readjustment) and Toxic effect, which proved SBRM as a time-dependence model based on the time series BS data. Meanwhile, it was found that SBRM showed evident stress-dependence. Therefore, it was concluded that medaka SBR was both stress-dependent and time-dependent, which supported and developed SBRM, and data mining by SOM could be efficiently used to illustrate the behavioral processes and to monitor toxic chemicals in the environment.  相似文献   
26.
秦皇岛城市旅游CTIS形象设计研究   总被引:2,自引:0,他引:2  
在日趋激烈的国际城市旅游竞争中,若想取得一席之地,旅游城市需要构建系统的城市形象识别系统,即CTIS。城市CTIS系统需要在明确的市场定位基础上,通过构建旅游城市核心理念识别系统、行为识别系统及视觉识别系统实现。在对秦皇岛旅游市场进行STP(市场细分—目标市场选择—市场定位)分析的基础上,提出秦皇岛建设"健康之都"的城市定位,并且构建了相关城市CTIS系统内容。  相似文献   
27.
关于安全行为科学的探讨   总被引:9,自引:3,他引:6  
对安全行为科学的有关问题进行了初步探讨,阐述了研究安全行为科学的意义,给出了安全行为科学的概念,提出了安全行为科学的研究方法和基本内容  相似文献   
28.
为研究水田土壤中氮的行为,施给15NH4 或15NO3-标记的硝胺(NH415NO3或15NH4NO3)的沙壤土(Shirasu soil)添充在根箱里,对Japonica水稻(品种Hinohikari)进行温室栽培6周.收割后,水稻植株分地上部和根部,对各自的全氮,15N atom%进行测定.根箱各区域的土壤按着鲜土形态进行采取后,对此全氮,NO3-N,水溶性NH4-N,KCl抽出NH4-N和其各自的15N atom%进行测定.研究结果表明,土壤全氮含量与栽培前相比,在非根际明显降低,但在根际比非根际要高,保持了与栽培前相同的水平.土壤NO3-N浓度从非根际到根际递增,但与其栽培前相比显著地降低,在整个根箱里,施给NO3-N的79%为因脱氮而损失.土壤中NO3-N的大部分来自于土壤氮化合物,来自施肥的比例却较低,尤其是在根际.反而,施给NO3-N的残存率约仅为16%左右,但其中有机态氮所占的比率在非根际里55%~86%,在根际却达到了93%.土壤水溶性NH4-N和KCl抽出NH4-N浓度靠近根际逐渐降低,而且在非根际两者匀由1∶10的比例存在,但在根际里水溶性NH4-N没被检索到.在非根际里,土壤KCl抽出NH4-N的35%~66%为来自施肥,但其比例在根际里却降到15%左右.在土壤中残存的来自施给NH4-N的氮化合物之中,有机态氮所占的比例在非根际里约为11%~65%,但在根际却达到了92%.以上结果表明,在水稻根际,氮的无机化和有机化的活性比非根际显著.  相似文献   
29.
The terms ‘coexistence’, ‘tolerance,’ and ‘acceptance’ appear frequently in conservation literature, but lack consistent characterization, making them difficult to apply across intervention frameworks. This review aims to describe the common characterizations of these three terms using Africa-based research as a case study. Through systematic lexical searches, we identified 392 papers containing one or more of the three terms. We assessed their usage, definition, and measurement (or lack thereof) in wildlife conservation. Coexistence was used in 46% of papers, but was defined in only 2% and measured in 4%. Tolerance and acceptance were used in 63% and 61% of the papers in which they appeared, respectively, defined in 4% and 2%, and measured in 19% and 5%. These results confirm the lack of clear understanding of these concepts and evidence the need for a precise lexicon. This would allow conservationists to cohesively describe their work and increase replicability of research across contexts.Electronic supplementary materialThe online version of this article (10.1007/s13280-020-01352-6) contains supplementary material, which is available to authorized users.  相似文献   
30.
This paper explores the hypothesis that contextual environments (media exposure and social exposure) and biospheric value orientation are important antecedents to the attitude-intention-behavior model ( [Ajzen, 2001] and [Ajzen, 2002] ) in the context of environmental psychology. Data for this investigation were obtained from a random sample of 2106 (1073 males and 1025 females) high school students in Hong Kong. A path analysis demonstrates that adolescents’ social exposure and media exposure are associated with biospheric value orientation. The biosperhic value orientation is found to mediate between the contextual variables (media exposure and social exposure) and environmental attitude. This environmental attitude, in turn, mediates the relationship between this value orientation and behavioral intention to act environmentally. Results show that both adolescents’ behavioral intention and degree of social exposure are associated with their environmental behavior. Overall, this article provides empirical support for the proposed path model. The article concludes by presenting theoretical and practical implications for future research in environmental psychology.  相似文献   
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