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91.
In many cases, the first step in large‐carnivore management is to obtain objective, reliable, and cost‐effective estimates of population parameters through procedures that are reproducible over time. However, monitoring predators over large areas is difficult, and the data have a high level of uncertainty. We devised a practical multimethod and multistate modeling approach based on Bayesian hierarchical‐site‐occupancy models that combined multiple survey methods to estimate different population states for use in monitoring large predators at a regional scale. We used wolves (Canis lupus) as our model species and generated reliable estimates of the number of sites with wolf reproduction (presence of pups). We used 2 wolf data sets from Spain (Western Galicia in 2013 and Asturias in 2004) to test the approach. Based on howling surveys, the naïve estimation (i.e., estimate based only on observations) of the number of sites with reproduction was 9 and 25 sites in Western Galicia and Asturias, respectively. Our model showed 33.4 (SD 9.6) and 34.4 (3.9) sites with wolf reproduction, respectively. The number of occupied sites with wolf reproduction was 0.67 (SD 0.19) and 0.76 (0.11), respectively. This approach can be used to design more cost‐effective monitoring programs (i.e., to define the sampling effort needed per site). Our approach should inspire well‐coordinated surveys across multiple administrative borders and populations and lead to improved decision making for management of large carnivores on a landscape level. The use of this Bayesian framework provides a simple way to visualize the degree of uncertainty around population‐parameter estimates and thus provides managers and stakeholders an intuitive approach to interpreting monitoring results. Our approach can be widely applied to large spatial scales in wildlife monitoring where detection probabilities differ between population states and where several methods are being used to estimate different population parameters.  相似文献   
92.
A prevailing view in dryland systems is that mammals are constrained by the scarcity of fertile soils and primary productivity. An alternative view is that predation is a primary driver of mammal assemblages, especially in Australia, where 2 introduced mesopredators—feral cat (Felis catus) and red fox (Vulpes vulpes)—are responsible for severe declines of dryland mammals. We evaluated productivity and predation as drivers of native mammal assemblage structure in dryland Australia. We used new data from 90 sites to examine the divers of extant mammal species richness and reconstructed historic mammal assemblages to determine proportional loss of mammal species across broad habitat types (landform and vegetation communities). Predation was supported as a major driver of extant mammal richness, but its effect was strongly mediated by habitat. Areas that were rugged or had dense grass cover supported more mammal species than the more productive and topographically simple areas. Twelve species in the critical weight range (CWR) (35–5500 g) that is most vulnerable to mesopredator predation were extirpated from the continent's central region, and the severity of loss of species correlated negatively with ruggedness and positively with productivity. Based on previous studies, we expect that habitat mediates predation from red foxes and feral cats because it affects these species’ densities and foraging efficiency. Large areas of rugged terrain provided vital refuge for Australian dryland mammals, and we predict such areas will support the persistence of CWR species in the face of ongoing mammal declines elsewhere in Australia.  相似文献   
93.
Estimation of small mammal population sizes is important for monitoring ecosystem condition and for conservation. Here, we test the accuracy of standard methods of population size estimation using Capture-Mark-Recapture (CMR) on a simulated population of agents. The use of a computer simulation allows complete control of population sizes and behaviors, thereby avoiding assumptions that may be violated in real populations. We find that the recommended protocol for CMR sampling, using uniformly distributed traps, consistently overestimates population sizes by as much as 100% when studies are conducted over only two trapping periods. More than 20 trapping periods are required before this method, or that of placing traps randomly, gives an accurate estimation of population size (i.e., within a 95% confidence limit of the actual value). Non-random sampling, by placing traps on runways used by small mammals, produces the most accurate, and least variable, estimates of population. However, we show that around 10 trapping periods are still required to produce an accurate population estimate using this method. Given that most real populations do not comply with the ‘ideal’ assumptions made by CMR, we suggest that population estimates based on CMR may be fundamentally flawed, and recommend that protocols for CMR population estimation methods may need revising.  相似文献   
94.
国土空间规划体制具有强烈生态指向意义,生态安全已是国土空间安全的重点。以四川省威远县为研究对象,针对县域生态国土空间的生态资源破坏、生态系统紊乱等问题,利用生态—社会经济系统耦合方法,从要素修复、结构优化、系统价值提升三个角度构筑系统耦合度评价指标体系,计算系统耦合度及子系统综合功效,综合耦合系统时空格局变化分析得出县域生态修复安全目标格局与生态修复对策。研究结果表明:(1)县域生态修复规划具有目标多层次性、系统复合性及途径多样化性,可从宏、中、微观层级提出对策。(2)系统耦合度在0.457~0.497区间浮动,耦合系统现处于拮抗时期向磨合时期发展。(3)依据系统耦合度、子系统综合功效及指标影响度构建“点—线—面”的生态修复格局。研究提出应对县域尺度的生态修复专项规划方法和实践运用,可为当前县域国土空间规划编制提供新的思路和方法。  相似文献   
95.
Over the past two decades, communication on environmental values, actions and performance has become an essential activity of organisations, because of the increased public concern and legislation related to the environment.

Stakeholders put pressure on companies to take environmental responsibility. In this framework, an effective environmental communication can generate value-added on companies' environmental work, and consequently, their competitiveness and profitability can benefit from communicating their environmental responsibility.

In 2006, the International Organization for Standardization (ISO) launched a standard for environmental communication, ISO 14063. ISO 14063 should not be used for third-party certification purposes. Instead, it is intended to be used as a guideline and support companies to ensure successful environmental communication. The aim of this paper is to prompt a discussion about the applicability of the standard ISO 14063 not only to single organisations but as a tool to plan the environmental communication strategy of a whole territorial area. This is achieved by performing a case study relating to the Interreg IVC-funded project “Progresland”. The project involved three Italian and one Spanish natural areas and demonstrated that ISO 14063 could be a valid support to define and implement an environmental communication plan for a territorial area.  相似文献   
96.
通过梳理国内外海陆统筹实践进程和政策演变,界定海陆统筹的基本概念与内涵,在国土空间规划背景下,探讨海陆统筹的关键问题和挑战,并进一步提出海陆统筹的优化路径。研究表明:(1)海陆统筹是一种“流”空间理论思维下面向全域全要素的开发保护战略,通过统一筹划海陆两大系统的资源要素配置、产业联动、生境共治、空间互联和制度互嵌,促进沿海地区协同高效发展,提升生产、生活和生态空间品质。(2)国土空间规划视角下海陆统筹面临的主要问题与挑战包括:海陆空间边界不明晰、海陆经济系统不协调、海陆资源开发与生境保护不统一和海陆空间规划体系不兼容。(3)针对现状问题与挑战,基于空间、经济、生态和管治四个维度,构建全域全要素、分级、分功能的统筹优化路径,以期为沿海地区的海陆协调发展提供借鉴。  相似文献   
97.
可持续城市研究进展及其对国土空间规划的启示   总被引:1,自引:0,他引:1  
可持续城市是很多学科和领域关注的焦点。智能化和网络社会的演进促进了技术与可持续发展的关系研究,可持续城市研究亟需创新理论和方法。国内学界对可持续城市的前沿关注不够,结合国土空间规划的反思和探讨欠缺。因此,借助CiteSpace软件对国内外可持续城市研究进行系统评述,分析其演进脉络和研究热点,并探讨其对国土空间规划的启示。可持续城市研究主要经历了萌芽、兴起、增长、扩散四个阶段。可持续城市应当以自然、社会和技术三者的协调发展为核心。可持续城市的国际研究主要集中在气候变化、城市治理和智慧城市三个方面,并由“可持续”向“可持续智能”转变,大数据辅助城市规划成为趋势,社区多元主体共治逐渐增强。新可持续智能城市研究框架与国土空间规划的结合将是未来研究的关键。中国需要加强可持续智能城市的研究和实践,提出科学的可持续智能城市评价指标体系,结合国情重视城乡共治,并将这些理念渗透在国土空间规划中。  相似文献   
98.
在计算机上实现国土资源综合评价指标体系的研究   总被引:1,自引:0,他引:1  
本文首先探讨并提出了一套国土资源综合评价体系及相应的评价指标,然后介绍了在计算机上如何建立资源评价指标自动生成系统及如何利用这个系统产生所需要指标的方法,并指出这一领域需要继续深入研究的问题,为区域性资源开发研究评价的自动化提供了经验。  相似文献   
99.
洞庭湖区退田还湖过程中小型兽类的生态位特征   总被引:1,自引:0,他引:1  
为了解退田还湖工程实施后的小兽群落状况,2003~2010年对洞庭湖区退田还湖后9种不同类型生境中小型兽类的生态位特征进行了调查.共布放64 432夹日,捕获小型兽3 066只,总的捕获率为4.76%,包括啮齿目10种和食虫目2种.小型兽类各种群的生态位宽度以褐家鼠和黑线姬鼠最高,分别为0.819 8和0.765 6,为广生态位的种类;随后依次是臭鼩、东方田鼠、刺猬、巢鼠、黄胸鼠、小家鼠、黄毛鼠、针毛鼠,分别为0.689 0、0.573 7、0.527 3、0.482 8、0.394 8、0.289 7、0.265 1、0.098 5;社鼠和大足鼠最低,仅在1种生境中有捕获.从生态位宽度指数的季节变化看,黑线姬鼠、褐家鼠、东方田鼠和臭鼩在四季的生态位宽度指数均较高.从空间生态位宽度和生态位重叠指数看,除黑线姬鼠和褐家鼠利用生境较广外,洞庭湖小兽群落可分为3个类群:栖息于环湖丘岗林地生境的社鼠、针毛鼠和黄毛鼠类群,以湖滩生境为主的东方田鼠、巢鼠和臭鼩类群,以及以村庄周围的农田生态系统为主的家鼠类群.从生态位指标和捕获数量看,黑线姬鼠、东方田鼠和褐家鼠是当地需要重点关注的种类.东方田鼠种群数量高峰年份与低谷年份比,其生态位宽度以及与其它种类的生态位重叠指数均较高,高峰年份东方田鼠冬季在双退垸出现,说明退田还湖已扩大了东方田鼠的繁殖基地,对东方田鼠种群发展有利,在种群暴发年份,易形成更加严重的危害.  相似文献   
100.
The return of willow ptarmigans to the sites in which they nested the previous year has been studied using color banding. No factors influencing the return index have been revealed, except for its dependence in males on the time when spring begins in a given year. In northernYamal, in contrast to the temperate zone, some surviving birds fail to return to their former nesting sites. Polymorphism of individuals with respect to territorial behavioral strategy is proposed for L. lagopus populations at the northern boundary of the species range.__________Translated from Ekologiya, No. 3, 2005, pp. 215–221.Original Russian Text Copyright © 2005 by Tarasov.  相似文献   
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