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101.
《Anthrozo?s》2013,26(2):125-130
ABSTRACT

Although a number of studies have examined a range of demographic and personality variables that may impact upon attitudes towards the treatment of non-human species, little consensus has been reached within the literature. The aim of the current study was to evaluate and assess levels of human-directed empathy and attitudes towards the treatment of animals in two diverse populations, namely the general community (n = 543) and those within the animal protection field (n = 389). Both groups of participants completed the Attitude Towards the Treatment of Animals Scale (AAS) and the Davis Interpersonal Reactivity Index (IRI), a measure of human-directed empathy. Comparisons between the two samples indicated that those within the animal protection community scored more highly on both the animal attitude and human-directed empathy measures. Correlational analyses revealed a positive relation between AAS and IRI scores for both samples, whilst the strength of the correlation was greater for those within the animal protection sample. These findings are discussed.  相似文献   
102.
This study presents a new technological approach to minimize the use of antimicrobial (AMB) agents and their deleterious effects, based on the principle of drug-delivery systems whereby the AMB chemicals are transported on microparticles. The efficacy of microparticles carrying the quaternary ammonium compound (QAC), benzyldimethyldodecyl ammonium chloride (BDMDAC), was assessed against Pseudomonas fluorescens in both the planktonic and the biofilm state. The microparticles were prepared using a layer-by-layer (LBL) self-assembly technique. Oppositely charged molecules of polyethyleneimine (PEI), sodium polystyrene sulfonate (PSS), and BDMDAC were assembled on polystyrene (PS) cores. BDMDAC-coated particles were observed by CryoSEM and their composition analyzed by X-ray microanalysis. Zeta potential measurements indicated that changes in surface charge were compatible with a BDMDAC/particle interaction. This biocidal carrier structure had significant stability, verified by the release of only 15% of the BDMDAC when immersed in water for 18 months. Biocidal carrier activity was evaluated by determining the survival ratio of P. fluorescens planktonic and biofilm cells after different exposure periods to BDMDAC-coated particles. Tests with biofilm cells were also performed with the free QAC. An efficient AMB effect (minimum bactericidal concentration) against suspended cells was found for a concentration of 9.2 mg l?1 of BDMDAC on coated particles after incubation for 30 min and 6.5 mg l?1 of BDMDAC on coated particles after 60 min. Exposure of biofilms to PS-PEI/PSS/BDMDAC (0.87 mg l?1) resulted in a decrease in viability of 60.5% and 66.5% of the total biofilm population for 30 and 60 min exposure times, respectively. Exposure for 60 min to 6.33 mg l?1 and 11.75 mg l?1 of BDMDAC in PS-PEI/PSS/BDMDAC particles promoted inactivation of 80.6% and 87.2% of the total population, respectively. The AMB effects obtained with the application of free BDMDAC were statistically similar to those promoted by the application of BDMDAC coated particles. The overall results indicate that this novel AMB strategy has potential for the control of microbial growth of planktonic cells and biofouling. Moreover, the technique allows the reuse of AMB molecules and consequently reduces the environmental risks associated with excessive use of AMB agents, thereby providing real benefits to public health.  相似文献   
103.
Interest in the management of the environment and its resources on an ecosystem basis has been increasing, in both terrestrial and marine contexts. In recent years, the concept of the large marine ecosystem has become a point of focus at the national and international levels as a possible unit for management of ocean and coastal areas. An ecosystem approach, however, challenges the manner in which marine resources and the environment that sustains them have been managed in the past. Governance is a key element in ecosystem management and encompasses the formal and informal arrangements, institutions, and mores that determine how resources and the environment are utilized. This study explores some of the problems, concepts, and principles involved in efforts to provide needed governance arrangements if large marine ecosystem-based management is to be implemented and made effective.  相似文献   
104.
105.
Paternity protection and the acquisition of multiple mates select for different traits. The consensus from theoretical work is that mate‐guarding intensifies with an increasing male bias in the adult sex ratio (ASR). A male bias can thus lead to male monogamy if guarding takes up the entire male time budget. Given that either female‐ or male‐biased ASRs are possible, why is promiscuity clearly much more common than male monogamy? We address this question with two models, differing in whether males can assess temporal cues of female fertility. Our results confirm the importance of the ASR: guarding durations increase with decreasing female availability and increasing number of male competitors. However, several factors prevent the mating system from switching to male monogamy as soon as the ASR becomes male biased. Inefficient guarding, incomplete last male sperm precedence, any mechanism that allows sperm to fertilize eggs after the male's departure, and (in some cases) the unfeasibility of precopulatory guarding all help explain cases where promiscuity exists on its own or alongside temporally limited mate‐guarding. Shortening the window of fertilization shifts guarding time budgets from the postcopulatory to the precopulatory stage.  相似文献   
106.
Seed potato crops are currently sprayed weekly with mineral oil to prevent transmission of the Potato virus Y (PVY; Potyviridae: Potyvirus), one of the most prevalent and important non‐persistent viruses affecting potato production. In spite of its wide usage as inhibitor of virus transmission, the mode of action for mineral oil is poorly known. The objective of this study was to quantify the effect of dosage and time from application of mineral oil on the inhibition of PVY acquisition. The bird cherry‐oat aphid, Rhopalosiphum padi (L.) (Hemiptera: Aphididae), known as vector of PVY, was used in all the experiments. The results indicated that mineral oil efficiently decreased PVY acquisition by 75 and 70% 1 day after application of 5 and 10 l ha?1, respectively. The inhibition effect decreased with time from application; mineral oil inhibits acquisition for less than 4 days at 5 l ha?1 and between 8 and 12 days at 10 l ha?1. As mineral oil was detected in the body of fewer aphids when they fed on plants 1 day after oil application, a change in the aphid probing behaviour on mineral oil‐treated plants was deduced. These results support the hypothesis that mineral oil physically inhibits the binding of the virus at the tip of the stylets.  相似文献   
107.
茉莉酸对棉花单宁含量和抗虫相关酶活性的诱导效应   总被引:4,自引:0,他引:4  
杨世勇  王蒙蒙  谢建春 《生态学报》2013,33(5):1615-1625
以植物生长调节物茉莉酸(Jasmonic acid,JA)为诱导子,以常规棉为研究对象,探讨了外源茉莉酸对棉花幼苗单宁和蛋白酶抑制素以及其它抗虫相关酶活性诱导的浓度依赖性和持久性,讨论了棉花抗虫相关物质的抗虫效果.结果表明,0.01、0.1和1.0 mmol/L茉莉酸都能在2周内诱导棉花单宁和胰蛋白酶抑制素(Proteinase inhibitors,PIs)含量增加,诱导多酚氧化酶(Polyphenol oxidase,PPO)、苯丙氨酸解氨酶(Phenylalanine ammonia-lyase,PAL)、过氧化物酶(Peroxidase,POD)和过氧化氢酶(Catalase,CAT)活性升高.对3种浓度茉莉酸的诱导效应进行分析表明,0.1 mmol/L茉莉酸对于诱导PIs、PPO、POD和CAT最有效,0.1和1.0 mmol/L茉莉酸对于诱导棉花单宁和苯丙氨酸解氨酶等效,二者的诱导效应均高于0.01 mmol/L.对茉莉酸诱导抗性的持久性进行分析表明,最佳诱导效应发生的时间各不相同:POD活性在JA处理后第1天最高,随后呈下降趋势,PIs和单宁含量分别在JA处理后第7天和第14天达最大值;JA处理后第1天和第7天的PPO活性无明显差异,但明显高于第14天;JA处理后第7天和第14天的PAL活性无明显差异,但明显高于第1天;JA处理后第1、7和14天棉花叶片的CAT活性均无明显差异.以上结果表明,茉莉酸可通过增加棉叶单宁和PIs含量、提高棉叶PAL、PPO、POD和CAT活性等增强棉花幼苗的抗虫性.  相似文献   
108.
生态系统生产总值核算:概念、核算方法与案例研究   总被引:26,自引:0,他引:26  
生态系统产品与服务功能是人类生存与发展的基础。生态系统生产总值(GEP)可以定义为生态系统为人类福祉和经济社会可持续发展提供的产品与服务价值的总和,包括生产系统产品价值、生态调节服务价值和生态文化服务价值。生态系统生产总值核算的基本任务有3个,即核算生态系统产品与服务的功能量、确定生态系统产品与服务的价格、核算生态系统产品与服务的价值量。生态系统生产总值核算可以用于揭示生态系统为经济社会发展和人类福祉的贡献,分析区域之间的生态关联,评估生态保护成效和效益。以贵州省为例,探讨了生态系统生产总值核算的应用方法,评价了贵州省生态系统为贵州和其他地区人们福祉和支撑经济社会发展所提供的产品和服务及其经济价值总和。评价结果显示,贵州省2010年全省生态系统生产总价值为20013.46亿元,人均GEP 57526元,是当年该省国民生产总值和人均GDP的4.3倍。研究表明,生态系统生产总值的核算可以反映生态系统对经济社会发展的支撑作用,并为建立生态系统保护效益与成效的考核机制提供基础。  相似文献   
109.
湿地自然保护区保护价值评价方法   总被引:6,自引:3,他引:3  
孙锐  崔国发  雷霆  郑姚闽 《生态学报》2013,33(6):1952-1963
提出了一套侧重水鸟保护的湿地自然保护区保护价值评价方法.该方法建立的指标体系经过专家咨询和会议讨论确定指标,采用层次分析法(AHP)建立了递阶层次结构模型.指标体系共分为目标层1项、系统层5项、准则层11项和指标层26项.将获取资料的湿地自然保护区按国家有关分类标准与原则归为3个类型(海洋与海岸生态系统类型、内陆湿地与水域生态系统类型和野生动物类型),每个类型内的自然保护区再结合自身湿地主体进一步划分为4个小类型(近海与海岸湿地、河流湿地、湖泊湿地、沼泽湿地).实例分析了海洋与海岸生态系统类型中的以近海及海岸湿地为主体的自然保护区,内陆湿地与水域生态系统类型中的以沼泽湿地为主体的自然保护区和野生动物类型中的以河流湿地为主体的自然保护区,并依照保护价值指数进行了等级划分.为湿地自然保护区的保护价值和发展地位,总体规划和改建变更提供了依据.  相似文献   
110.
三江源牧户参与草地生态保护的意愿   总被引:1,自引:0,他引:1  
李惠梅  张安录  王珊  张雄  杨海镇  卓玛措 《生态学报》2013,33(18):5943-5951
牧民对环境保护的响应是生态保护战略有效实施的关键,主体参与意愿直接影响生态保护项目实施的成效和可持续性,是区域生态经济可持续发展的前提。通过对三江源地区约283户藏族牧民通过翻译进行结构式访谈,采用Logistic模型从主体角度探讨了牧户愿意参与生态保护行为响应的主要影响因素。结果表明:(1)三江源区域约87%的牧户认为生态保护对牧户有好处,但受各种内外部因素的影响只有近70%的牧户是在政府主导下基于有限理性而被动的参与生态保护行为响应。(2)三江源牧户参与生态保护行为响应的意愿主要受当地政府的保护力度及牧户对生态保护外部性的认知水平、生计水平、外界接触程度、工作机会的正影响,并受牧户的年龄、离中心城镇的距离和区域气候恶劣情况等因素的负影响,系数依次为:2.22、3.98、1.93、2.26、1.48、-1.63、-2.43、-0.92。(3)牧户的生计水平、退化感知和外部性认知是影响三江源牧户参与生态保护意愿的关键因素,牧户参与生态保护意愿的概率不仅仅是牧户出于自身利益和未知风险考虑下被动的响应,更是当地政府的环境知识宣传和保护投入影响下个体的抉择结果。(4)创造更多的就业机会和解决牧户的单一化生计问题,构建完善地生态补偿机制让牧户分享生态保护的外部性效益,并激励牧户主动参与生态保护行为响应,才能最终实现区域生态保护、牧户幸福和生态经济可持续发展的多赢局面。  相似文献   
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