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1.
The “value of information” (VOI) is a generic term for the increase in value resulting from better information to guide management, or alternatively, the value foregone under uncertainty about the impacts of management (Yokota and Thompson, Medical Decision Making 2004; 24 : 287). The value of information can be characterized in terms of several metrics, including the expected value of perfect information and the expected value of partial information. We extend the technical framework for the value of information by further developing the relationship between value metrics for partial and perfect information and describing patterns of their performance. We use two different expressions for the expected value of partial information to highlight its relationship to the expected value of perfect information. We also develop the expected value of partial information for hierarchical uncertainties. We highlight patterns in the value of information for the Svalbard population of the pink‐footed goose (Anser brachyrhynchus), a population that is subject to uncertainty in both reproduction and survival functions. The framework for valuing information is seen as having widespread potential in resource decision making, and serves as a motivation for resource monitoring, assessment, and collaboration.  相似文献   

2.
生态产品价值实现是指在维持生态系统稳定性和完整性的前提下,通过合理开发利用生态产品,将其生态价值转化为经济效益的过程。生态产品价值实现机制包含了促进生态产品价值实现的政策、市场和技术机制。生态产品通过各种途径实现的经济价值总和称为生态产品价值实现量。生态产品价值实现量与生态产品总值(GEP)的比值为生态产品价值实现率。评估生态产品价值实现率是评判生态产品价值实现状况的基础,是评估生态产品价值实现机制是否有效运转的重要前提。提出生态产品价值实现率的概念和核算方法,以浙江省丽水市为例,在核算GEP的基础上,评估生态产品价值实现量与实现率来分析丽水市生态产品价值实现状况、问题及影响因素,提出提高生态产品价值实现率的对策建议。研究表明,丽水市2019年GEP为4110.21亿元,生态产品价值实现量为1017.49亿元,生态产品价值实现率为24.76%。丽水生态产品价值实现模式主要有市场交易和政府补偿两种模式。市场交易模式贡献了95.84%的生态产品价值实现量,是目前丽水市最有效的生态产品价值实现模式,但存在价值实现效率不均衡、对于缺乏市场或是市场机制不成熟的生态产品不适用等问题。政府补偿模式贡...  相似文献   

3.
王妍  李欣茹  张甜甜  徐建英 《生态学报》2023,43(22):9446-9458
自然保护区的生态系统服务(Ecosystem Service,ES)的社会文化价值,是支持自然保护区多元化发展、践行生态文明建设的重要路径。以北京市百花山自然保护区为例,结合社会调查数据和地理空间数据,在对生态旅游者和一般游客有效分类的基础上,使用SolVES模型、相关性分析和社会网络分析等方法探索二者对研究区ES社会文化价值的认同差异、空间差异、作用关系差异及影响因素差异。研究发现:(1)生态旅游者对ES社会价值的价值认同比一般游客高,特别体现在学习、生物多样性、精神和生命可持续价值这4种价值类型上;(2)百花草甸是两类游客ES社会价值分布的热点区域,生态旅游者感知的美学、学习、生物多样性、精神和生命可持续价值的高值区的分布范围较一般游客更广,一般游客感知的娱乐和康体健身价值的高值区的分布范围较生态旅游者更广;(3)两类游客均认为不同ES社会价值类型间为协同关系,其中学习价值对生态旅游者而言是最具影响力的社会价值类型,生物多样性、精神、生命可持续和未来价值对一般游客而言是最具影响力的社会价值类型;(4)对旅游设施的满意度显著影响两类游客对关键价值类型的评估,但影响方式不同。此外对环境教育的满意度和是否知道百花山是国家级自然保护区分别是影响生态旅游者和一般游客对关键价值类型评估的社会要素,NDVI和ELEV分别是影响生态旅游者和一般游客对关键价值类型评估的空间要素。建议在自然保护区生态旅游的规划建设中,需要考虑不同游客对ES社会价值的感知差异,积极探索协同ES社会价值的供给,支持自然保护区自然资源管理和生态旅游规划。  相似文献   

4.
鲁春霞  刘铭  冯跃  武建双  冷允发 《生态学报》2011,31(24):7370-7378
随着羌塘草原野生动物种群规模的扩大,草食性野生动物与家畜争夺草场的矛盾愈来愈突出.生态补偿无疑是解决这一矛盾的重要途径之一,而进行野生动物的生态服务价值评估是建立生态补偿标准的基础.通过羌塘地区社会经济资源环境现状调查和人群支付意愿调查,并采用直接市场法和虚拟市场法,对西藏自治区羌塘地区草食性野生动物藏羚羊的生态经济价值进行了评估.把藏羚羊的生态经济价值分为利用价值包括商业价值、游憩娱乐价值、维持生物多样性的价值、教育美学价值和科学研究价值,以及非利用价值包括存在价值、遗产价值、选择价值两大类.对野生动物生态价值的评估结果表明,羌塘地区藏羚羊的生态服务价值高达7.51亿元/a.其中,藏羚羊的利用价值为6.35亿元/a,非利用价值为1.16亿元/a.也就是说,羌塘地区15万只藏羚羊每年产生的生态服务价值远高于羌塘自然保护区涉及的6个县域2007年的总产值4.79亿元.  相似文献   

5.
四川省森林植被固碳经济价值动态   总被引:3,自引:1,他引:2  
<正>确估算森林植被固碳经济价值可为森林生态系统的生态效益评价提供基础数据。利用1997年和2014年两期四川省森林资源清查数据,依据不同森林类型的生物量与蓄积量回归方程和支付意愿法,估算了四川省两个时期森林植被的固碳经济价值。结果表明,从1997年到2014年,四川省森林植被固碳经济价值由703.17亿元增长到865.75亿元,净增长162.58亿元,年均增长9.56亿元,年均增长率为1.36%;在两个时期,云冷杉林的固碳经济价值比重最大,分别占总固碳经济价值的54.82%和46.62%,表明云冷杉森林植被类型在全省森林植被固碳经济价值中占有重要的地位;四川省天然林和人工林植被的固碳经济价值均呈增加趋势,并且人工林植被固碳经济价值年均增长速率(7.42%)明显高于天然林(1.03%);四川省森林植被固碳经济价值总体上随林龄的增加而增加。研究结果说明,实施包括天然林保护工程在内的森林保护和经营管理措施对提高森林植被的固碳经济价值具有重要的作用。  相似文献   

6.
We have measured mean value of RHz, mean value of R2G1/2z, and mean value of Mw for individual fractions of the protein alpha-crystallin obtained by gel filtration of bovine lens nuclear extracts. A strong and monotonic decrease of mean value of RHz and mean value of Mw with increasing elution volume could be observed, indicating a broad size distribution. The experimental results are quantitatively consistent with a polymerization of monomeric units into linear chains, which may have a certain degree of flexibility. Using theoretical expressions for mean value of R2G and mean value of RH originally derived for semiflexible polymers in solution, we can self-consistently analyse the data from static and dynamic light scattering, and from electron microscopy experiments. We thus obtain detailed information on the molecular weight distribution and the quaternary structure of alpha-crystallin in these solutions.  相似文献   

7.
王凤珍  周志翔  郑忠明 《生态学报》2011,31(7):1946-1954
城郊过渡带湖泊湿地面临着改善城市居民生活环境及满足城郊过渡带经济发展的双重压力,承担着更多样、更重要的生态服务功能,从生态服务功能价值分量的基础上探讨开发利用对策,可为其可持续开发利用提供依据。本文以武汉市城郊过渡带湖泊湿地严东湖为研究对象,基于市场价值法、影子工程法、旅行费用法、条件价值法等方法对严东湖生态服务功能的直接、间接使用价值及非使用价值进行了货币化计量。结果表明,严东湖生态服务功能的总价值为35799.09?104元?a-1,其中直接使用价值、间接使用价值及非使用价值分别为2628.80?104、2904.13?104、30266.16?104元?a-1,表现为非使用价值>间接使用价值>直接使用价值,且非使用价值约是其使用价值的5.5倍。12个单项指标中为存在价值最高;使用价值中为涵养水源价值>蒸腾吸热价值>均化洪水价值>休闲旅游价值>科研教育价值>物质生产价值>生物多样性维持价值>固碳释氧价值>水质净化价值;非使用价值中为存在价值>遗产价值>选择价值。因此,城市过渡带湖泊的开发利用应保护现有湖面的完整性,保持涵养水源、蒸腾吸热及均化洪水功能,弱化养殖类物质生产功能,适度发展休闲旅游功能,提高固碳释氧能力,并增强水质净化能力。  相似文献   

8.
A dual-function fluorescent probe (Probe 1) was developed in this work for the separate detection of pH value and formaldehyde (HCHO). Probe 1 could recognize HCHO and the pH value from the amino group. The colour of the probe solution was changed from grey blue to light blue with the increase in the pH value, and luminous intensity became larger with the increase in formaldehyde concentration. The curve function relationship between fluorescence intensity and the pH value was also determined. A smartphone containing a colour detector for imaging was used to record the values of the three primary colours (R value, G value, and B value) for the probe solution in formaldehyde. Importantly, there was a linear functional relationship between the B*R/G value with HCHO concentration. Therefore, the probe could be used as a rapid tool for the detection of formaldehyde. More importantly, Probe 1 was successfully used to detect formaldehyde in an actual distilled liquor sample.  相似文献   

9.
Wildlife value orientations are patterns of basic beliefs that give direction and meaning to fundamental values in the context of wildlife. Wildlife value orientations can help managers estimate public evaluations to management interventions. Their usefulness, both practically and scientifically, depends on their predictive potential. This article examined the predictive value of wildlife value orientations on the acceptability of wildlife management interventions in different situations. The situations varied in (a) severity of the human wildlife problem and (b) severity of the interventions for wildlife. Two wildlife value orientations were measured: domination (human needs have priority over wildlife well-being, 10 items) and mutualism (rights are assigned to wildlife, 9 items). Acceptability was measured as a dichotomous variable for management interventions across 5 different situations. The predictive value of wildlife value orientations was largest for acceptability of the most severe interventions (hunting, 35–42% of variance explained), followed by the least severe interventions (doing nothing, 5–17%) and the intermediate interventions (shaking eggs or applying contraceptives, 1–9%) in the scenarios that include a problem for humans. Value priorities appear to be an integral feature of value orientations. Intermediate interventions do not harm wildlife, but might solve the problem caused by wildlife. Such interventions also create minimal small internal value conflicts. Orientations that prioritize values and offer a template for conflict resolution are likely to have less predictive potential for these interventions.  相似文献   

10.
Kelp beds, besides being one of the most important benthic resources in northern Chile, provide a variety of environmental goods and services. In order to evaluate economically the wild kelp populations in northern Chile (26° to 32° S) more than simply their commercial value as a source of raw materials for alginate extraction, we used several economic indicators to holistically assess the value of a group of brown seaweeds of economic importance, Lessonia spp. and Macrocystis pyrifera: (1) market value of biomass as a source of raw material for extraction of alginic acid, (2) market value of associated species of economic importance, (3) value as a source of scientific information, (4) value as a climate buffer (CO2 capture and release of O2), (5) value of associated biodiversity (non-commercial species), (6) value as cultural heritage and (7) value as a reservoir of biodiversity. Existence values of kelp beds which estimate the willingness of citizens to pay and work without payment to preserve the ecosystem were calculated using the contingent valuation technique. The results indicate that kelp beds in northern Chile have a total value of US $540 million. Of this total, kelp fishery accounts for 75 % and associated-species fisheries account for 15 %. In this context, the economic value of Chilean kelp beds is mainly associated with the industry of alginate extraction. By contrast, existence value as a source of scientific information or environmental buffer for CO2 capture or O2 production represents only 9 % of the total value, representing a very low relative importance to society. The economic valuation of coastal resources and marine ecosystems is a complementary tool for decision making and implementation of public policies related to the conservation and sustainable exploitation of renewable resources and their ecosystems.  相似文献   

11.
S T Kim  A Sancar 《Biochemistry》1991,30(35):8623-8630
Photolyases reverse the effects of UV light on cells by converting cyclobutane dipyrimidine photoproducts (pyrimidine dimers, Pyr mean value of Pyr) into pyrimidine monomers in a light-dependent reaction. Previous work has suggested that, based on substrate preference, there are two classes of photolyase: DNA photolyase as exemplified by the Escherichia coli enzyme, and RNA photolyases found in plants such as Nicotiana tabacum and Phaseolus vulgaris. In experiments aimed at identifying substrate determinants, including the pentose ring, for binding and catalysis by E. coli DNA photolyase we tested several Pyr mean value of Pyr. We found that the enzyme has relative affinities for photodimers of T mean value of T greater than or equal to U mean value of T greater than U mean value of U much greater than C mean value of C and that the E-FADH2 form of the enzyme repairs these dimers at 366 nm with absolute quantum yields of 0.9 (T mean value of T), 0.8 (U mean value of T), 0.6 (U mean value of U), and 0.05 (C mean value of C). The enzyme also repairs an isolated thymine dimer and the synthetic substrate, 1,1'-trimethylene-bis (thymine) cyclobutane dimer. Unexpectedly, we found that this enzyme, previously thought to be specific for DNA, repairs uracil cyclobutane dimers in poly(rU). The affinity of photolyase for a uracil dimer in RNA is about 10(4)-fold lower than that for a U mean value of U in DNA; however, once bound, the enzyme repairs the photodimer with the same quantum yield whether the dimer is in ribonucleoside or deoxyribonucleoside form.  相似文献   

12.
保障粮食安全造成的生态价值损失评估模型及应用   总被引:1,自引:0,他引:1  
粮食安全和生态安全是我国政府必须切实解决的关系到社会经济发展、人民生活质量提高和社会稳定的重大战略问题。借鉴前人的生态服务价值理论与评估模型的基础上,阐明了保障粮食安全造成的生态服务价值损失的内涵,并以理论分析为依据,分别构建了评估不同类型生态服务价值损失的模型,为了验证所构建模型的可操作性和实用性,以陕西省长武县为案例区,对其2008年保障粮食安全导致的生态价值损失进行了评估,在不同类型生态服务价值损失中,由于不同生态系统的合理转换引起的生态服务价值损失为22834.16×104元;如果将长武县所有粮食生产用地作为林地、草地、水体,与作为耕地相比,可为人们多提供的生态服务价值分别为:21963.30×104元、4095.04×104元、40678.82×104元;单位面积林地、草地、水体可以多提供的生态服务价值量,最高的是水体,为19682.34元/hm2,林地和草地分别为:10627.4元/hm2和1981.37元/hm2。  相似文献   

13.
中国森林生态资产价值评估   总被引:4,自引:4,他引:4  
森林资源是支撑人类社会发展的重要生态资产,探索森林生态资产价值的评估方法,对合理利用和有效保护森林资源具有重要意义。运用净现值法计算了中国森林生态资产总价值为698.5万亿元,其中直接价值为7.5万亿元,包括林木价值4.5万亿元和林下产品价值3.0万亿元;间接价值为691万亿元,其中,气候调节价值量最高,占间接价值的48%;水源涵养价值量次之,占间接价值的27%。从森林生态资产总价值的分布来看,广西省、广东省和云南省位于全国前列,分别占森林生态资产总价值的10%、9%和9%。单位面积森林生态资产价值表现为海南省、浙江省和广东省较高,分别为954万元/hm2,915万元/hm2和888万元/hm2。森林生态资产价值研究为我国编制自然资源资产负债表提供理论依据,因此全面的估算中国森林生态资产价值很有意义。  相似文献   

14.
A. Gallais 《Genetics》1990,124(1):199-206
The line value of a genotype is defined as the expected value of all lines that can be derived from this genotype. Specific genetic effects are defined for this value: only additive and additive by additive epistatic effects are necessary. There is no dominance effect for such a value. A general expression for the covariances between related lines is given. From a design with several lines per haplodiploidized plant taken at random from a population it is possible to estimate the additive variance for line value and the variance of additive by additive epistasis for line value. Variances of higher order epistasis can be estimated with a two-factor mating design in which a cross is replaced by the population of lines that can be derived from it. With a diallel or a factorial design a direct test for the presence of homozygous by homozygous epistasis is possible. The application of the concept of line value to the theory of line development leads to simple expressions of genetic advance in one cycle of recurrent selection according to the testing system. A brief consideration of these expressions leads to the conclusion that single doubled haploid descent recurrent selection will be one of the most efficient methods for low heritabilities and with a rapid development of doubled haploid lines.  相似文献   

15.
Daubner SC  Fitzpatrick PF 《Biochemistry》1999,38(14):4448-4454
The active site of tyrosine hydroxylase consists of a hydrophobic cleft with an iron atom near the bottom. Within the cleft are several charged residues which are conserved across the family of pterin-dependent hydroxylases. We have studied four of these residues, glutamates 326 and 332, aspartate 328, and arginine 316 in tyrosine hydroxylase, by site-directed substitution with alternate amino acid residues. Replacement of arginine 316 with lysine results in a protein with a Ktyr value that is at least 400-fold greater and a V/Ktyr value that is 4000-fold lower than those found in the wild-type enzyme; substitution with alanine, serine, or glutamine yields insoluble enzyme. Arginine 316 is therefore critical for the binding of tyrosine. Replacement of glutamate 326 with alanine has no effect on the KM value for tyrosine and results in a 2-fold increase in the KM value for tetrahydropterin. The Vmax for DOPA production is reduced 9-fold, and the Vmax for dihydropterin formation is reduced 4-fold. These data suggest that glutamate 326 is not directly involved in catalysis. Replacement of aspartate 328 with serine results in a 26-fold higher KM value for tyrosine, a 8-fold lower Vmax for dihydropterin formation, and a 13-fold lower Vmax for DOPA formation. These data suggest that aspartate 328 has a role in tyrosine binding. Replacement of glutamate 332 with alanine results in a 10-fold higher KM value for 6-methyltetrahydropterin with no change in the KM value for tyrosine, a 125-fold lower Vmax for DOPA formation, and an only 3.3-fold lower Vmax for tetrahydropterin oxidation. These data suggest that glutamate 332 is required for productive tetrahydropterin binding.  相似文献   

16.
袁继安  宁晨  田大伦 《生态学报》2019,39(19):7283-7294
选取湖南省2016年优势树种森林资源为研究对象,核算了林地、林木、生态服务、森林资源负债与净资产的价值。根据核算结果编制了森林资源资产负债表。结果表明,2016年优势树种林地总价值4938.00亿元,较上年增长12.84%,其中杉木、阔叶林和马尾松林地价值合计占比达91.86%。林地单位面积价值为54797.23元/hm~2。林木账面价值达到3385.06亿元,较上年增长2.19%。其中阔叶树、杉木和马尾松林木账面价值占总价值比重为95%;单位面积平均价值为37564.15元/hm~2。2016年生态服务价值3304.39亿元,较上年增长2.36%,单位面积生态服务价值36669元/hm~2。各生态服务价值在总价值中占比在1.81%(积累营养物质)到25.68%(涵养水源)之间。征占林地等4类森林资源损害因素共计减损森林面积和蓄积分别为1.35万hm~2和48.77万m~3。因此造成的森林资源负债金额由高到低依次为征占林地(618.26亿元)森林火灾(505.48亿元)乱砍滥伐(236.65亿元)毁林开荒(67.12亿元)。林地资产、林木资产和生态服务价值占森林资源总资产价值的比重分别为42.47%、 29.11%和28.42%。森林资源资产负债率为0.26%,资本积累率为6.50%。  相似文献   

17.
森林生态系统土壤保持价值的年内动态   总被引:4,自引:0,他引:4  
李士美  谢高地  张彩霞  祁悦 《生态学报》2010,30(13):3482-3490
以定位观测数据位基础,选用日雨量模型和通用土壤流失方程,研究了5种森林生态系统土壤保持价值的年内动态。研究表明,季节雨林、次生林、人工橡胶林、阔叶红松林和次生白桦林的土壤保持价值分别为570.29、347.87、174.65、14.31元.hm-.2a-1和8.76元.hm-.2a-1。土壤保持价值各月分配不均,5-10月的土壤保持价值占全年土壤保持价值的80%以上。西双版纳3种森林生态系统土壤保持价值构成中,保持土壤养分的价值高达60%以上。长白山2种森林生态系统的土壤保持价值构成有所不同,阔叶红松林以减少泥沙淤积价值为主,而次生白桦林以保持土壤养分价值为主。土壤保持价值构成中,减少废弃地价值的不足总价值的10%。  相似文献   

18.
养殖池塘生态系统文化服务价值的评估   总被引:1,自引:0,他引:1  
池塘养殖在我国已经有几千年的历史.这种生产模式不仅具有经济功能,还具有文化价值.随着我国经济与文化水平的提高,这种价值将会进一步凸显.对其生态服务价值的评估,可为渔业经济政策的制订提供科学支撑,避免政策扭曲及其所产生的政策失灵,科学地发展水产养殖业及相关休闲服务业,增加养殖经济的附加值,进而提高渔民收入,促进农村经济发展.本文以上海市青浦区淀山湖水源保护区养殖池塘作为研究对象,以实证调查数据为基础,结合该区的相关统计数据,将养殖池塘的文化价值分为游憩价值和存在价值, 并在此基础上,以旅游成本法(TCM)和条件价值评估法(CVM)分别对这两种价值进行了估算,测算了总的文化服务价值.结果表明:该区养殖池塘文化服务总价值约为每年2.13亿元,约合231296.69元·hm-2, 是该池塘养殖水产品产量市场价值的5.25倍.其中游憩价值约为1.89亿元,存在价值0.24亿元.在推动上海新农村建设的过程中,职能部门需重新认识此类系统的价值.  相似文献   

19.
草地植物作为生物燃料供给料已经被人们所提及,而植物的热值和灰分含量作为评价生物燃料质量的重要指标,却很少被人们研究。本文通过对内蒙古锡林河流域羊草草原5种多年生禾本科植物(羊草、冰草、大针茅、羽茅和隐子草)的热值和灰分进行测定,探讨了植物热值和灰分的月变化及二者之间相关性。结果表明:5种植物干重热值及去灰分热值月变化均为单峰形变化曲线,干重热值的最大值出现在8月(19.2MJ·kg-1),去灰分热值最大值出现的月份因植物种类不同而表现一定的差异;灰分含量的月变化趋势表现为先降低后升高;冰草、大针茅和隐子草干重热值与灰分含量之间表现为极显著线性负相关(P<0.01),羽茅干重热值与灰分之间表现为显著线性负相关(P<0.05),而羊草干重热值与灰分含量之间的相关性不显著。  相似文献   

20.
宁夏贺兰山东麓葡萄产业生态系统服务功能价值评估   总被引:1,自引:0,他引:1  
利用宁夏回族自治区统计局、宁夏回族自治区葡萄产业发展局和国家统计局等的相关统计数据,从食品生产、固碳释氧、净化大气、土壤保持、涵养水源、节水增效、生态旅游和生态扶贫等角度,对宁夏贺兰山东麓葡萄产业生态系统服务价值进行评估.结果表明: 1)宁夏贺兰山东麓葡萄产业生态系统服务功能价值为35.98亿元,其中直接效益为22亿元,生态效益为13.98亿元.生态效益占整个产业生态系统服务价值的38.85%.2)生态效益中,各项功能的价值量依次为: 生态扶贫>生态旅游>固碳释氧>节水增效>净化大气>土壤保持>涵养水源.3)生态效益中,生态扶贫的价值最高,占64.39%;生态旅游的价值次之,占24.47%.对葡萄产业进行生态系统服务功能价值评估,既可以让人们在看到葡萄产业直接效益的同时,又可以意识到葡萄产业所带来的生态效益.这对全面指导葡萄产业健康持续发展具有重要参考价值.  相似文献   

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