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61.
Social insects, i.e. ants, bees, wasps and termites, are key components of ecological communities, and are important ecosystem services (ESs) providers. Here, we review the literature in order to (i) analyse the particular traits of social insects that make them good suppliers of ESs; (ii) compile and assess management strategies that improve the services provided by social insects; and (iii) detect gaps in our knowledge about the services that social insects provide. Social insects provide at least 10 ESs; however, many of them are poorly understood or valued. Relevant traits of social insects include high biomass and numerical abundance, a diversity of mutualistic associations, the ability to build important biogenic structures, versatile production of chemical defences, the simultaneous delivery of several ESs, the presence of castes and division of labour, efficient communication and cooperation, the capacity to store food, and a long lifespan. All these characteristics enhance social insects as ES providers, highlighting their potential, constancy and efficiency as suppliers of these services. In turn, many of these traits make social insects stress tolerant and easy to manage, so increasing the ESs they provide. We emphasise the need for a conservation approach to the management of the services, as well as the potential use of social insects to help restore habitats degraded by human activities. In addition, we stress the need to evaluate both services and disservices in an integrated way, because some species of social insects are among the most problematic invasive species and native pests. Finally, we propose two areas of research that will lead to a greater and more efficient use of social insects as ES providers, and to a greater appreciation of them by producers and decision‐makers.  相似文献   
62.
?????? 目的 研究应用儿科临床路径管理的方法对住院医师规范化培训管理的价值。方法 采用对照研究的方法,用SPSS10.0软件计算χ2,确定统计学意义。结果 新方法的应用儿科理论成绩明显提高,住院医师定专业成功率提高,住院医师被患者投诉明显减少。结论 儿科临床路径管理应用于住院医师规范化培训管理,管理流程化,充分调动了培训医师的积极性和创新性,提高了学习效率和效果。  相似文献   
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目的:分析椎弓根入路行椎体后凸成形术(PKP)治疗骨质疏松性椎体压缩骨折的预后评价及继发危险因素分析。方法:选择2016年2月-2018年2月我院收治的骨质疏松性椎体压缩骨折患者85例纳入本次研究,采用随机数表法分为观察组(n=43)和对照组(n=42)。对照组使用经皮椎体成形术进行治疗,观察组采用PKP进行治疗。比较两组患者手术情况、术后情况、椎体前缘高度丢失率、Cobb角、继发性骨折发生情况及分析骨质疏松性椎体压缩骨折患者术后继发骨折的危险因素。结果:观察组手术时间、透视次数、骨水泥注入量、术中出血量均显著低于对照组,差异显著(P0.05);观察组疼痛缓解时间、下地时间及住院时间均显著低于对照组,差异显著(P0.05);治疗前,两组椎体前缘高度丢失率、Cobb角比较,无显著差异;治疗后,两组患者的椎体高度丢失率明显下降,但两组术后7 d、术后6月两组椎体前缘高度丢失率、Cobb角比较无显著差异;观察组术后12月椎体前缘高度丢失率、Cobb角低于对照组,差异显著(P0.05);所有患者均随访12月,其中22例(25.88%)发生继发性椎体骨折,进行单因素分析,结果发现,两组患者性别、骨折部位、局部矢状面后凸角度、骨水泥量、椎体高度恢复、术后抗骨质疏松治疗差异无统计学意义(P0.05);骨质疏松原因、骨水泥椎间隙渗漏、术后支具佩戴、原发骨折类型与骨质疏松性椎体压缩骨折患者术后发生继发骨折相关(P0.05)。多因素Logistic分析显示,骨质疏松原因、骨水泥椎间隙渗漏、术后支具佩戴、原发骨折类型均是骨质疏松性椎体压缩骨折患者术后发生继发骨折的独立危险因素(P0.05)。结论:在骨质疏松性椎体压缩骨折患者中应用PKP可有效改善手术情况,随着时间的延长,PKP更有利于维持患者椎体高度;骨质疏松原因、骨水泥椎间隙渗漏、术后支具佩戴、原发骨折类型是骨质疏松性椎体压缩骨折患者术后发生继发骨折的危险因素,临床上对于具有危险因素的患者引起重视,并采取干预措施。  相似文献   
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65.
In this article, our objective is to introduce economics as a tool for the planning, prioritization, and evaluation of restoration projects. Studies that develop economic estimates of public values for ecological restoration employ methods that may be unfamiliar to practitioners. We hope to address this knowledge gap by describing economic concepts in the context of ecological restoration. We have summarized the most common methods for estimating the costs and benefits of restoration projects as well as frameworks for decision analysis and prioritization. These methods are illustrated in a review of the literature as it applies to terrestrial restoration in the United States, with examples of applications of methods to projects. Our hope is that practitioners will consider collaborating with economists to help ensure that restoration costs and benefits are identified and understood.  相似文献   
66.
Aims Despite the current interest in services provided by ecosystems and the role of biodiversity, the relationship among human attitudes, biodiversity and ecosystem services has hardly been investigated. Moreover, few studies have examined attitudes toward nature in cross-cultural comparisons. This study investigates the attitudes of Chinese and Swiss people, both environmental experts and laypersons, toward forest biodiversity and ecosystem services.Methods Overall, 640 people in China and Switzerland were interviewed with the help of a standardized questionnaire. In each country, the study population was equally divided into an urban (80 city dwellers and 80 environmental science students) and a rural (80 forest visitors and 80 farmers) study group. The 15-minute interviews took place in the cities of Beijing and Zurich and in the rural forested areas of Dujiangyan, Sichuan Province and Lake Sempach, canton Lucerne. Attitudes toward forest biodiversity were investigated with the help of color photographs that depicted both monocultures and species-rich forests typical for China and Switzerland. Attitudes toward ecosystem services were investigated with the help of 13 statements on provisioning, regulating, cultural and supporting services of forests.Important findings On average, Chinese participants showed no strong preferences for biodiversity, whereas the Swiss clearly preferred species-rich forests over monocultures. However, Chinese environmental science students did prefer species-rich forests and attributed to them a higher conservation value because of their higher biodiversity. Although there were no strong preferences for Chinese versus Swiss forests, all participants correctly answered that Chinese forests are more species rich in terms of plants and animals and thus found them less boring and more interesting, but also less managed, than Swiss forests. All participants highly valued the ecosystem services provided by forests; especially the regulating and supporting ones. Environmental science students and farmers placed more importance on the provisioning services, whereas city dwellers and forest visitors emphasized more on the regulating services. The disjuncture between the high ecological quality of species-rich forests and their low attractiveness to Chinese study participants points to a potential conflict between conservation policies and the public's preferences. A better communication of ecosystem services provided by forest biodiversity to the public might change these preferences in favor of ecological quality, as already observed among Chinese environmental science students.  相似文献   
67.
68.
赵玉  张玉  熊国保  严武 《生态学报》2018,38(5):1698-1710
赣江是中国最大淡水湖鄱阳湖水系的第一大河流,为流域内两千多万常住人口提供着重要的生态系统服务。研究赣江生态系统服务价值及其支付意愿可为建立和实施流域生态补偿机制提供决策依据。在随机效用理论框架下采用Tobit模型和实际调查数据,分析了居民对赣江生态系统服务的支付意愿及其影响因素,并运用条件价值评估法测算了赣江生态系统服务价值。可能的亮点在于,第一,将心理距离、心理所有权等微观因素纳入生态系统服务支付意愿模型中,通过测算心理变量对支付意愿影响的偏效应,探讨了提升生态系统服务支付意愿的可行路径;第二,比较分析了河流上、中、下游居民生态系统服务支付意愿的差异,并探讨了支付意愿异质性产生的原因。结果表明:(1)除居民收入和年龄外,对赣江环境治理满意度、支付偏好、对环保部门的信任度、与河流的心理距离、对河流的心理所有权也是影响其支付意愿的主要因素。(2)赣江生态系统服务支付意愿的区域异质性是由上、中、下游居民支付偏好、对环保部门信任度和收入的差异造成的。(3)满意度、信任度、心理距离和心理所有权的平均偏效应分别为7.22、3.84、2.7、1.85元/户。(4)赣江流域WTP预测值的中位数为19.57元/户,其中,南昌、吉安和赣州每户居民每月愿意支付的金额分别为23.24、19.70、16.86元,赣江为流域居民创造的生态系统服务价值为13.60亿元/a,其中,南昌段、吉安段和赣州段的生态系统服务价值分别为4.31亿元/a、3.21亿元/a和4.65亿元/a。最后,基于研究结论提出了相应的政策建议。  相似文献   
69.
我国重点保护动植物物种价值评估   总被引:1,自引:0,他引:1  
对野生动植物生态经济价值的认识是有效保护的基础,运用条件价值评估法对我国重点保护动植物物种的价值进行研究。通过网络问卷调查法共收集到5500份问卷,其中有效问卷4672份。通过对有效问卷分析得到总的平均支付意愿为209元人~(-1)a~(-1)。其中,动物和植物分别是111.37元人~(-1)a~(-1)和97.65元人~(-1)a~(-1),不同保护级别物种的支付意愿大小差别显著。基于2016年全国城镇就业人口数据求得我国重点保护动植物物种的保护效益为18.29万亿元/a,其中动物8.20万亿元/a,植物10.09万亿元/a。支付意愿影响因素分析表明,收入、学历、对重点保护物种的了解和感兴趣程度以及是否参加过重点保护物种保护活动对支付意愿大小有显著影响。  相似文献   
70.
王朋薇  钟林生 《生态学报》2018,38(15):5279-5286
生态系统服务价值评估是生态系统保护和管理的基础。以往研究采用多种方法对生态系统服务价值进行评估,但是至今还未形成得到一致认可的生态系统服务价值的评估方法。协商货币评估法(Deliberative Monetary Valuation,DMV)将协商方法和陈述偏好法相结合,成为一种正在探索使用的新的货币评估法。分析了DMV的研究背景,并从DMV的独特适用性、DMV在生态系统服务价值评估中的应用、DMV获得价值的性质3个方面总结了DMV的主要研究内容,在此基础上阐述了DMV面临的挑战,并提出了DMV在中国生态系统价值评估应用中的启示,以期能够为DMV在中国的应用及推广提供借鉴,为生态系统服务价值评估探索更有效的方法。  相似文献   
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