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71.
秦岭自然保护区群保护成本计量研究 总被引:5,自引:0,他引:5
秦岭自然保护区群在我国生物多样性保护方面发挥了重要作用,学术界一直缺乏保护成本计量的研究。本研究在界定秦岭自然保护区群成本的概念及分析其内涵的基础上,综合运用专家咨询法及文献参考方法,建立了秦岭自然保护区群保护成本计量指标体系,利用市场价值法、等效替代法以及机会成本法等方法,对秦岭自然保护区群保护生物多样性的投入进行了成本计量及分析。结果表明:秦岭自然保护区群在保护生物多样性投入方面,总货币量约29.72亿元人民币,其中直接保护成本为2.59亿元;间接保护成本为2.00亿元;与周边区域密切相关的机会成本为25.13亿元。其中,机会成本的计量模型多样化,在学术界存在较多争议,但是,最终每种模型都能反映出机会成本的内涵的货币量,可以表达出我国政府为建立秦岭自然保护区群而付出的无形代价。 相似文献
72.
Contrary to the assumptions of many previous theoretical models, group size has recently been shown in experiments to have
an effect on the relative (as well as absolute) competitive abilities of group members. Here we introduce a novel and effective
mathematical tool for describing how relative competitive ability will change for any two specified individuals within a group
as group size changes. We show that there is no simple general rule for describing how relative competitive ability will change
with group size. A subsequent empirical test of the model helps to illustrate that very specific knowledge of the system under
study is needed in order to produce robust predictions.
Received: 23 December 1998 / Received in revised form: 26 July 1999 / Accepted: 2 October 1999 相似文献
73.
Environmental and social factors influence chorusing behaviour in a tropical frog: examining various temporal and spatial scales 总被引:3,自引:0,他引:3
Many animals use conspicuous display to attract mates, and there should be selection for displays to occur at times and places
that maximise the probability of mating, while minimising energetic costs and predator attraction. To select the best times
for display, individuals may use environmental cues, the presence of other individuals, or both, but few studies have examined
these sources of variation in display activity. In this study, we examined physical environmental and social factors triggering
displays in a tropical, terrestrially breeding frog, Cophixalus ornatus. To measure the influence of physical environmental conditions on calling activity, we recorded temperature, rainfall, moon
illumination/visibility, humidity, barometric pressure and intensity of calling activity throughout a breeding season at six
locations along a 560-m transect. The intensity of calling varied daily, seasonally, and at a small spatial scale. Variation
in calling activity from day to day was large. There was also a strong seasonal trend in calling activity: few males called
at the start of the season, activity peaked shortly after the beginning of the season, and then declined linearly from the
peak to the end of the season. There was also consistent variation among sites along the transect, which may have been due
to variations in frog density at each site, or to consistent microscale variations in physical conditions, or both. After
statistically removing consistent local variation among sites, a principal components analysis suggested that a maximum of
35.8% of the variation in calling activity among days was due to factors common to all sites, such as weather, moon illumination,
or large-scale social facilitation (e.g. of choruses by other choruses). The remainder of the variation among sites (64.2%)
was due to site-specific factors, such as small-scale social facilitation or unmeasured, apparently stochastic effects, such
as microenvironmental physical factors that do not vary consistently over sites. Regressions of environmental variables on
residual calling activity (after removing consistent effects of site and season), alone or in combination, accounted for very
little of the variation in the number of calling males (maximum 10%). Thus, our data, showing strong seasonal effects and
consistent variation among sites combined with large amounts of variation in the number of calling males at small spatial
scales, suggest that environmental conditions, such as temperature, rainfall, moon illumination and barometric pressure, which
act over large spatial scales, may determine the overall environmental envelope within which calling can occur but do not
account for most of the variation in the number of calling males on a day-to-day or site-to-site basis. Similarly, variations
in the number of calling males at small spatial scales suggest that social facilitation is a relatively unimportant trigger
for displays on a large scale in these frogs. On the other hand, our data suggest that social facilitation may have important
effects on variation in the number of calling males on a day-to-day and site-to-site basis. We used playback experiments to
assess whether the sound of calling could initiate displays. We played either a taped chorus or white noise in areas where
few (zero to two) males were calling. The number of calling males increased both during and after the chorus stimulus, whereas
there was no increase in calling in response to white noise. These data suggest that examining variation in calling activity
at small spatial scales can reveal the sources of variation for the number of calling males, and indicate that, in these frogs,
males tend to use the calling of other individuals as a cue to determine when to display.
Received: 19 October 1999 / Revised: 30 June 2000 / Accepted: 26 August 2000 相似文献
74.
Experimental evidence for a dual pathway model analysis of coping with the climate crisis 总被引:1,自引:0,他引:1
Martijn van Zomeren Russell Spears Colin Wayne Leach 《Journal of environmental psychology》2010,30(4):339
Two experiments examined the psychological power of fear and group efficacy beliefs to increase environmental action intentions against the climate crisis. Extending a dual pathway model of coping with collective disadvantage, results showed evidence for emotion-focused approach coping: Environmental action intentions were increased by individuals' manipulated fear of the negative future consequences of the climate crisis (Experiments 1–2). Additionally, results showed evidence for problem-focused approach coping: Individuals' measured (Experiment 1) and manipulated group efficacy beliefs (Experiment 2) increased environmental action intentions. The results thus suggest that the dual pathway model can be successfully applied to a psychological analysis of emotion- and problem-focused approach coping with the climate crisis. We discuss the theoretical and practical implications of these results. 相似文献
75.
Yaoqian Zhong Bingxin Xia Jianwu Shi Ping Ning Chaoneng Zhang Xinyu Han Jiming Hao 《Frontiers of Environmental Science & Engineering》2022,16(9):114
76.
利用Hysplit、MeteoInfo模型,计算株洲2017—2019年特护期(10月至次年3月)的后向轨迹,并进行轨迹聚类、潜在源贡献因子(PSCF)和浓度权重轨迹(CWT)分析。结果表明,10—12月,污染物潜在源区主要分布在偏北方向,1—3月,偏南方向的源区不断扩大,这与季节更替、季风转换有关;12和1月,潜在源区面积最大,强度最强,传输通道最清晰。对特护期各月份进行权重潜在源贡献因子(WPSCF)和加权浓度权重轨迹(WCWT)分析,结果表明,12月有1条明显的WPSCF高值带起源于河南省中北部,一路向南,经平顶山、过南阳、再经襄阳进入湖北省,该高值带蛇形前进,过荆州跨长江经岳阳华容县进入湖南,再过常德、益阳,以弧形路径到达长株潭地区,这条路径是12月北方污染物影响长株潭的主要传输通道。WCWT分析也有类似结果,且通道路径更宽广,1月的潜在源区在偏北方向呈扇形分布,在较远距离上的河南、安徽等省份呈指状分布。经2017年12月5日重污染个例检验发现,传输轨迹与分析的传输通道一致。 相似文献
77.
燕山期环太平洋构造活动导致辽西频繁地火山喷发。巨星火山灰一次次覆盖火山周围丛林和湖沼.掩埋了各种生物,形成学术价值极高的化石库(fossillagerstatte),尤其是鸟类和昆虫化石及动物的毛发、羽毛、膜翅及内脏等软组织结构,都或多或少地以精细的碳化膜或印痕保存。特别是近年一系列新发现,如孔子鸟(Confucinsornis)和带毛的秀颌龙(Compsognathus)/中华龙鸟(Sinosauroteryx)等,引起国内外学术界的轰动。笔者研究了其中一批化石,从古生态和埋藏事件进行探讨认为:(1)该生物群代表分子中鹦鹉嘴龙(Psittacosaurus)、带毛秀颌龙/中华龙鸟及孔子鸟等,很可能是温血动物。(2)频繁的火山喷发不但将巨量的火山灰沉积在广大的湖泊丛林区,加快了其沼泽化的进程,对煤层及油页岩层的形成起了催化作用。 相似文献
78.
聚类分析在江汉湖群典型湖泊分类中的应用 总被引:1,自引:0,他引:1
江汉湖群中的许多通江湖泊由于自然和人为原因失去了与长江及其支流的天然联系,对湖泊生态和湖区经济可持续发展造成了不利影响,重建江湖联系对湖泊生态环境改善和湖区经济发展意义重大。根据4项选择标准,选取江汉湖群中13个典型湖泊作为研究对象,以有关社会经济、生态等方面的调查统计数据为基础,利用聚类分析的方法对江汉湖群中的13个阻隔湖泊进行分类。根据所挑选的16个指标将这些湖泊划分为4大类,并对各类湖泊特点进行了分析,确定了这些湖泊的通江顺序。 相似文献
79.
Qualitative and Quantitative Assessment of Land-Use Managers' Attitudes Toward Environmental Justice
This study examines the outcome of efforts to educate federal land-use managers about their roles in implementing the Executive
Order in their respective districts. The managers participated in a 6-h Nominal Group Technique (NGT) workshop where they
were instructed to weight environmental justice issues versus others associated with hazardous waste problems in their districts.
Participant responses were quantified and analyzed through a series of rounds. After each round, participants received increasing
amounts of information on environmental justice issues.
It was hypothesized that the managers would come to a consensus that environmental justice is an important issue that should
be seriously addressed. Prior to administering the NGT, the managers appeared to have limited knowledge of environmental justice
issues and thus assigned relatively low rankings to such concerns. After being “educated” by viewing films on environmental
justice and reading related literature, in general, managers' weightings decreased and a narrower consensus developed.
The authors conclude that exposure to the issue may not be as effective as expected in convincing land-use managers to become
sensitive to justice issues so that they may effectively implement the Executive Order. 相似文献
80.
We use a combination of the marginal value theorem (MVT) of Charnov (1976), and a group foraging model featuring information
sharing to address patch residence in an environment where food occurs in discrete patches. We shall show that among equal
competitors the optimal patch time for the individual that finds the food patch is shorter than that for the non-finder among
equal competitors, T
E < T
N. This is the case if the patch-finder commences food harvesting in the patch earlier and manages to monopolise a fraction
of the prey items (finder's advantage) before the other individuals come to take their benefit. When individuals differ in
their food-searching abilities so that some of them (producers) contribute proportionally more to food-searching than others
(scroungers), and differ in ability to compete for the food found, a difference emerges between producer and scrounger individuals
in the optimal patch time. Within a patch we always have the finder's advantage (T
E < T
N) regardless of phenotype. Between patches a suite of optimal patch times for encountering individuals emerges depending on
the performance of producers and scroungers when changing from solitary feeding to feeding in a group. The optimal patch time
for individuals that are affected more severely by competition is shorter than that for individuals of the phenotype with
better competitive ability. When both phenotypes are affected similarly no difference in optimal patch times emerges.
Received: 13 February 1996 / Accepted after revision: 28 September 1996 相似文献