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本文主要研究了肯尼亚姆瓦彻湾(属于浅潮滩红树林湿地)泥沙交换的动力机制.该港湾属于半日潮,大、小潮的潮差分别为.2m和1.4m,大潮高水位的水面面积为17km2. 相似文献
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The integrity of social insect colonies is maintained by members recognising and responding to the chemical cues present on the cuticle of any intruder. Nevertheless, myrmecophiles use chemical mimicry to gain access to these nests, and their mimetic signals may be acquired through biosynthesis or through contact with the hosts or their nest material. The cuticular hydrocarbon profile of the myrmecophilous salticid spider Cosmophasis bitaeniata closely resembles that of its host ant Oecophylla smaragdina. Here, we show that the chemical resemblance of the spider does not arise through physical contact with the adult ants, but instead the spider acquires the cuticular hydrocarbons by eating the ant larvae. More significantly, we show that the variation in the cuticular hydrocarbon profiles of the spider depends upon the colony of origin of the ant larvae prey, rather than the parentage of the spider. 相似文献
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Can Forest-protection carbon projects improve rural livelihoods? Analysis of the Noel Kempff Mercado climate action project,Bolivia 总被引:1,自引:0,他引:1
Asquith Nigel M. Vargas Ríos María Teresa Smith Joyotee 《Mitigation and Adaptation Strategies for Global Change》2002,7(4):323-337
We studied the Noel KempffMercado Climate Action Project (NKMCAP),Bolivia, to assess whether forestprotection carbon (C) projects cansignificantly benefit local people. Wehypothesized that forest protection canonly securely deliver C if significantstakeholders are meaningfully andtransparently involved, traditional orcustomary rights are recognized and theirloss compensated for, and there are directlinkages between conservation anddevelopment objective. Our researchfocused on 53 members of the communities ofFlorida, Porvenir and Piso Firme and 36secondary stakeholders. In each of thevillages we held half-day meetings withcommunity leaders, complemented bysemi-structured one-hour interviews with 5,10, and 7 families, representing 20%, 10%and 8% of each community. The long-termimpact of the NKMCAP on the localcommunities may well be positive. However,in the short run, certain sections of thelocal communities are financially poorer. Forest protection projects clearly have thepotential to sequester C, protectbiodiversity and simultaneously contributeto sustainable rural development, but ifthey really are to improve rurallivelihoods, they must be designed andimplemented carefully and participatively. 相似文献
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Foraging desert ants, Cataglyphis fortis, encounter different sequences of visual landmarks while navigating by path integration. This paper explores the question whether the storage of landmark information depends on the context in which the landmarks are learned during an ant's foraging journey. Two experimental set-ups were designed in which the ants experienced an artificial landmark panorama that was placed either around the nest entrance (nest marks) or along the vector route leading straight towards the feeder (route marks). The two training paradigms resulted in pronounced differences in the storage characteristics of the acquired landmark information: memory traces of nest marks were much more robust against extinction and/or suppression than those of route marks. In functional terms, this result is in accord with the observation that desert ants encounter new route marks during every foraging run but always pass the same landmarks when approaching the nest entrance. 相似文献
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Population differences in anti-predator behaviour have been demonstrated in several species, although less is known about the genetic basis of these traits. To determine the extent of genetic differences in boldness (defined as exploration of a novel object) and shoaling within and between zebrafish (Danio rerio) populations, and to examine the genetic basis of shoaling behaviour in general, we carried out a study that involved laboratory-raised fish derived from four wild-caught populations. Controlling for differences in rearing environment, significant inter-population differences were found in boldness but not shoaling. A larger shoaling experiment was also performed using one of the populations as the basis of a North Carolina type II breeding design (174 fish in total) to estimate heritability of shoaling tendency. A narrow-sense heritability estimate of 0.40 was obtained, with no apparent dominance effects. 相似文献
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M.?A.?de?FigueiredoEmail author D.?M.?Reiner H.?J.?Herzog 《Mitigation and Adaptation Strategies for Global Change》2005,10(4):647-657
This paper examines how legal standards of liability may apply to geologic carbon storage. The liability regime governing
geologic carbon storage will shape the technology's cost-effectiveness and overall attractiveness. We classify potential sources
of liability into operational, in situ, and climate liability. As a first step, we explore in situ liability in the United States. After summarizing legal standards of liability including negligence, breach of implied warranty,
strict liability, and product liability, we discuss how liability may be addressed at the level of the federal government,
state government, industry, and the firm. Finally, we address the implications of judicial treatment of liability for carbon
storage, including the apportionment of liability and the adequacy of current regulations. 相似文献
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