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1.
生态系统服务价值评估研究进展   总被引:100,自引:16,他引:84  
赵军  杨凯 《生态学报》2007,27(1):346-356
生态系统服务价值评估是当前生态经济学和环境经济学的研究热点和焦点。在系统回顾国内外生态系统服务价值评估研究进展的基础上,从研究对象、价值构成、研究方法、时空过程等4个方面对生态系统服务价值评估的当前特征进行了分析,探讨了价值评估中评估基础、评价方法以及结论应用等问题。指出国内必须加强生态系统服务理论和方法研究。展望了未来生态系统服务价值评估研究和工作的重点领域。  相似文献   

2.
石龙宇  郑巧雅  杨萌  刘玲玉 《生态学报》2022,42(14):6016-6029
在城市化快速进程中,不确定性的多元干扰对城市发展造成威胁,如何增强城市吸收、抵御、适应与学习能力是亟待解决的热点议题。韧性城市作为城市应对不确定性风险的新兴理念范式,对提高城市韧性水平与应变能力具备指导意义。对韧性概念进行辨析,阐述了城市韧性的概念,并提出多要素融合、多能力转变与多时空尺度的城市韧性概念见解。基于所提出的城市韧性概念,从过程化视角系统总结了多元干扰、城市系统状态、城市应对能力对城市韧性的影响。对单领域和多领域评估进行梳理,针对基于城市韧性要素、韧性特征、韧性实现过程的三种评估指标进行具体探讨,总结与比较了定性和定量的城市韧性评估方法。基于上述分析,提出当前存在缺乏城市如何实现韧性的研究、评估指标较少关注组织要素、多干扰和多主体、评估方法缺乏机理与动态模拟的应用、理论与落地实践脱轨等问题。最后提出未来展望,即注重城市韧性过程分析,设计更具完整性与针对性的指标体系,推动研究方法科学化与动态化改进,加强形成“机制-评估-管理”的可操作性闭环。  相似文献   

3.
生态系统服务建模技术研究进展   总被引:5,自引:4,他引:1  
李婷  吕一河 《生态学报》2018,38(15):5287-5296
在生态系统服务评估模型的数量、类型及应用大量增加的背景下,为将生态系统服务评估有效整合到决策中,系统比较、甄别不同建模工具并筛选出适合决策需求的生态系统服务评估和模拟方法尤为必要。因此,归纳并总结了国内外现有的生态系统服务评估模型的建模技术,包括:相关关系法、生物-物理过程法以及专家知识法;分别对其原理、差异、优缺点以及适用性进行了详尽阐释。大多数相关模型侧重于统计关系,相对容易创建和扩展,适用于生态系统服务的初始评估;生物-物理过程模型难以构建且不易获取,但提供了探索人-地系统相互作用和长期变化的有效机制;专家知识法有效结合了多种类型的知识体系,关注人类社会与自然系统之间反馈和交互动态的系统整合,但当评估地点发生变化时难以验证。在此基础上,介绍了基于上述3种建模技术的典型生态系统服务综合评估模型的发展和应用现状。各类建模技术面临着实用性和科学准确性之间的权衡。通过对不同建模技术的梳理与整合分析旨在提升当前生态系统服务研究的决策支撑能力,并为国内相关研究提供参考和借鉴。  相似文献   

4.
生物标志物(Biomarkers)在海洋环境监测中的研究与进展   总被引:3,自引:0,他引:3  
污染物的存在给海洋环境和生态健康带来了巨大的压力,如何监测这些污染物并对其毒性进行科学的评价,成为当今环境科学关心的热点问题。生物标志物(Biomarkers)是毒理学研究的重要工具,它能对污染事件进行早期预警,并能在一定程度上评估生态风险。对近十多年来生物标志物的研究与应用进行了回顾,总结了不同水平(分子、细胞、个体、系统)生物标志物的种类、特征、检测方法和应用特点,并对现存挑战和未来发展趋向进行了展望,旨在系统的认识生物标志物,并为其在海洋环境监测中的合理应用提供理论借鉴。  相似文献   

5.
海洋生态系统服务的研究进展   总被引:9,自引:0,他引:9  
综合了国际和国内对海洋生态系统服务的研究成果,总结归纳了海洋生态系统服务在基础理论、价值评估和应用研究等3个方面的进展.在众多的定义中,Daily(1997)的定义得到了生态学家们的普遍认可,而MA(2003)的概念更倾向于管理中应用.目前对生态系统服务的分类并不一致,MA的分类体系更为实用和便于评估.对海洋生态系统服务还缺乏系统的基础理论研究和适用的分类体系.在价值评估方面,多位学者对生态系统服务的社会价值与生态价值进行了探讨.尽管有多种技术方法可以了解人们的支付意愿,但对于不具有市场的服务价值的评估方法还有待进一步完善.应用研究主要集中在人类活动与生态系统服务之间的关系,以指导生态系统服务的管理与可持续利用.对如何更好地将生态系统服务的理论应用于实际管理和政策制定作了探讨与展望.  相似文献   

6.
生态系统服务价值评估方法综述   总被引:6,自引:0,他引:6  
基于相关科学研究文献,首先对生态系统服务价值评估的国内外研究现状进行追踪与分析;其次,从评估过程的角度,将生态系统服务价值评估方法分为两类:直接评估法和间接评估法,同时进一步对这两类方法进行了分类,并对分类后的评估方法在概念内涵、计算方法等方面进行了总结;最后,文章讨论了目前价值评估方面存在的问题,对生态系统服务价值的评估理论、评估方法及评估结果表现形式进行了总结,并对其未来发展方向提出了建议:加强不同生态系统服务价值评估方法的对比验证及综合应用研究,加强植被覆盖较少或无植被覆盖地区的生态系统服务价值评估研究,加强复合生态系统和精细尺度的生态系统服务价值评估研究。  相似文献   

7.
概述了大熊猫尿液样本采集和保存方法,系统总结了大熊猫尿液类固醇激素的提取方法、测定方法以及大熊猫尿液类固醇激素在应激反应监测、发情期监测及最佳配种时间选择、雌性卵巢功能和妊娠监测、雄性繁殖力评估等方面的应用研究,结合前人的研究工作,对大熊猫尿液类固醇激素的应用前景进行展望.  相似文献   

8.
姜广顺  李京芝 《兽类学报》2021,41(5):604-613
目前全球物种正以前所未有的速度灭绝,对野生动物栖息地开展有效的评估与科学的保护是阻止濒危物种走向灭绝,保持其可持续生存与发展的重要前提和手段。本文针对我国的食肉类、有蹄类、灵长类、小型兽类、海洋兽类5个类别的濒危兽类,综述了其栖息地评估与保护研究进展的现状和成果,对相关学术成果进行了归纳与分析,以期为栖息地的科学保护与管理梳理出系统、可供借鉴的研究方法和技术手段,并对其理论和技术的挑战进行了展望,提出了我国濒危兽类栖息地评估和保护研究应走向整体化、定量化、智能化,以及多学科交叉融合应用的“精准化”发展方向,为国家生态建设工程的有效实施提供重要技术支撑。  相似文献   

9.
论湿地生态系统服务的多维度价值评估方法   总被引:1,自引:0,他引:1  
宋豫秦  张晓蕾 《生态学报》2014,34(6):1352-1360
为了维系湿地生态系统的功能并制定合理的保护与开发规划,有必要量化湿地生态系统服务的价值。目前学术界尚未形成统一的湿地价值评估方法,而不同的选取方法、评估角度、评估对象等,会导致计算结果存在很大差异,尤其是在对时空差异性服务价值评估和湿地生态系统服务的总价值评估中存在难以量化和重复计算现象。针对上述问题,从湿地生态系统服务的定义、分类和受益人出发,提出了多维度价值评估方法,以定量计算时空差异性服务价值和系统的总服务价值,并探讨了该方法在淮河流域八里河湿地生态系统中的应用以及对其他类型生态系统服务研究的借鉴意义。  相似文献   

10.
土地利用/覆被变化与景观服务:评估、制图与模拟   总被引:2,自引:0,他引:2  
从景观尺度上探讨生态系统服务功能的研究越来越引起国内外学者的重视.相比生态系统尺度,景观尺度是探索人类活动对土地利用/覆被变化影响、探究可持续景观演变机理和过程的最佳尺度.基于对当前国际学界对景观服务研究进展的系统梳理与分析,本文探讨了景观服务的内涵与分类,并对景观服务价值评估、制图与模拟等研究方法进行归纳与分析,并对景观服务的未来研究趋势进行展望.景观服务研究的未来方向应进一步明确景观服务的内涵及其分类体系,不断完善和发展景观服务评估、制图与模型模拟方法,重点开展景观格局-过程-服务-尺度长期综合研究,继续加强景观生态学及景观经济学等理论与方法在景观服务研究领域中的应用.  相似文献   

11.
目的:通过优化现有的蛋白芯片检测过程,在保证检测准确性的同时缩短甲胎蛋白(Alpha Fetal protein,AFP)的检测时间,提高检测效率,为原发性肝癌的筛查提供经济、便捷、省时、有效的检测方法。方法:本研究在传统蛋白芯片检测流程(1-1.5小时)的基础上,通过优化检测流程将检测时间缩短至18分钟,并且通过和传统方法进行比较,评价该优化方法的检测效能。结果:与传统蛋白芯片检测方法相比,本优化方法的检测时间缩短至18分钟。重复检测同一样本,传统方法 AFP水平为16.50±1.172ng/m L,优化方法 AFP水平为18.33±1.029 ng/m L,结果无明显统计学差异(P=0.251)。结论:本研究成功地优化了AFP的蛋白芯片检测流程,在缩短检测时间的同时,保证了检测的准确率,是一种经济省时易操作的AFP检测方法。  相似文献   

12.
DELAY DISCOUNTING IN HUMANS WAS INVESTIGATED USING THREE DIFFERENT PROCEDURES: a frequently used discounting procedure with hypothetical rewards and delays; a procedure with hypothetical rewards and delays compressed down to much smaller values; and a contingent procedure in which each choice had a direct consequence. In the contingent procedure, on every trial, participants actually experienced the delay and obtained the reward amount associated with their choice. Each participant was exposed to all three procedures. Orderly temporal discounting patterns were obtained in all three procedures and described well by a hyperbolic model. Comparisons of the data revealed patterns unique to each procedure. The distributions of the discounting measures differed across the three procedures. In the contingent procedure, several subjects showed no discounting, e.g. complete self-control. Procedural factors in studies of impulsivity are discussed, and suggestions are offered for experiments in which the contingent-discounting procedure may prove useful.  相似文献   

13.
Primary clarifier effluent (procedure B) and final effluent (procedure A) from a wastewater treatment plant were enriched with Cryptosporidium parvum oocysts obtained from the feces of naturally infected calves. Procedure B samples alone were subjected to a laboratory simulation of activated-sludge treatment. Coccidium-free neonatal CD-1 mice were then inoculated intragastrically with procedure A or procedure B samples. Seven days after inoculation, the intensity of oocyst infection in procedure B mice was 91% less than in procedure A mice (controls).  相似文献   

14.
A sequential classification procedure with early elimination, for the screening for metabolic diseases, is presented. Asymptotic properties of the procedure are derived in the Appendix and it is shown that the procedure is asymptotically distribution-free under certain assumptions, and asymptotically at least as efficient as a comparable fixed-sample procedure. With the use of data obtained from 36 mentally retarded patients, the procedure was evaluated by means of a bootstrap simulation. The procedure was then applied to this set of data, with satisfactory results and a considerable economy in observations.  相似文献   

15.
Primary clarifier effluent (procedure B) and final effluent (procedure A) from a wastewater treatment plant were enriched with Cryptosporidium parvum oocysts obtained from the feces of naturally infected calves. Procedure B samples alone were subjected to a laboratory simulation of activated-sludge treatment. Coccidium-free neonatal CD-1 mice were then inoculated intragastrically with procedure A or procedure B samples. Seven days after inoculation, the intensity of oocyst infection in procedure B mice was 91% less than in procedure A mice (controls).  相似文献   

16.
This paper proposes a procedure for testing and classifying data with multiple factors. A two-way analysis of covariance is used to classify the differences among the batches as well as another factor such as package type and/or product strength. In the test procedure, slopes and intercepts of the main effects are tested using a combination of simultaneous and sequential F-tests. Based on the test procedure results, the data are classified into one of four different groups. For each group, shelf life can be calculated accordingly. We examine if the procedure produces satisfactory control of the probability of a Type I error and the power of detecting the difference of degradation rates and intercepts for different nominal levels. The method is evaluated with a Monte Carlo simulation study. The proposed procedure is compared with the current FDA procedure using real data.  相似文献   

17.
目的:探讨术前参观对择期进行心脏介入术患者心理焦虑的影响。方法:将400例择期行心脏介入手术的患者分为参观组和对照组,对照组术前采用常规护理干预,参观组患者在此基础上进行术前参观,熟悉环境,了解手术过程。调查比较两组患者术前2日及术前1小时的焦虑值。结果:参观组与对照组术前2日焦虑值无明显差异,术前1小时参观组焦虑值明显低于对照组,差异具有统计学意义(P0.05)。结论:通过术前参观能够减轻患者的焦虑程度。  相似文献   

18.
In 1972, a procedure was derived to cryopreserve mouse embryos. Over the past four decades, this procedure has been adapted to freeze embryos of more than twenty-five mammalian species. Cryopreservation of embryos has become a routine procedure in both veterinary and human medicine, having been used to freeze millions of embryos of mice and cattle, and many hundreds of thousands of human embryos. After transfer into appropriate foster mothers, cryopreserved embryos have developed into innumerable live offspring. This article describes the background that led to the derivation of the procedure and the events that transpired during its development. The first successful embryo cryopreservation procedure was developed by collaboration of three investigators, each bringing a special expertise and perspective to the project.  相似文献   

19.
A multiple-tubes procedure is described for using PCR to determine the genotype of a very small DNA sample. The procedure involves dividing the sample among several tubes, then amplifying and typing the contents of each tube separately. The results are analyzed by a statistical procedure which determines whether a genotype can be conclusively assigned to the DNA sample. Simulation studies show that this procedure usually gives correct results even when the number of double-stranded fragments in the sample is as small as 30. The procedure remains effective even in the presence of small amounts of laboratory contamination. We find that the multiple-tubes procedure is superior to the standard one-tube procedure, either when the sample is small or when laboratory contamination is a potential problem; and we recommend its use in these situations. Because the procedure is statistical, it allows the degree of certainty in the result to be quantified and may be useful in other PCR applications as well.  相似文献   

20.
A survey of food, feed, and pharmaceutical products was undertaken to compare an accelerated Salmonella detection procedure by enrichment serology (ES) to the traditional procedure outlined in the Bacteriological Analytical Manual (BAM). Excellent agreement between the two methods was obtained in the results of 689 test samples involving 35 different products. In addition to being more rapid and simpler to perform, the ES procedure was just as accurate and sensitive as the BAM procedure.  相似文献   

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