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991.
992.
Helvi Heinonen-Tanski Mariëlle SNEL Christine van Wijk-Sijbesma Avizit Reaz Quazi Kochurani Mathew Induka Werellagama Mujibur Rahman S.M.A. Rashid Palitha Jayaweera Helen Judith 《Environment, Development and Sustainability》2007,9(4):355-368
Environmental quality for environmental health has been examined visually by describing general conditions and drinking water
supply, sanitation and solid waste treatment conditions and practices in six South-East Asian villages with a dense population.
The environmental review was supplemented by discussions with local people and political and administrative decision makers.
Some drinking water analyses were done in order to show the water quality to the local people. The quality of the general
conditions and the conditions and practices of drinking water supply, excreta disposal and solid waste treatment practices
have been graded with the grading system presented below. The grading could be done in 1 or 2 days in each area by two persons,
of which one was an environmental scientist and the other a social scientist, who also knew the local culture and worked as
a translator. 相似文献
993.
Qinhua Fang Luoping Zhang Huasheng Hong Liyu Zhang Frances Bristow 《Environment, Development and Sustainability》2008,10(1):41-49
Environmental planning at different levels has been called for by environmental departments in China during last years to
integrate environment consideration to economic development. Based on the accomplished environmental planning practice in
Xiamen China, the paper suggests a general environmental planning process with ecological function zoning as its key steps,
at the same time an effective method for ecological function zoning was formulated. The case studies of Dongfu suburban town
environmental planning and Xiamen eco-city conceptual planning indicate that scientifically sound results of ecological function
zoning can contribute to improving not only the adaptability and acceptability of environmental planning, also the environmental
management and the decision-making. The experience shows that the ecological function zoning methods should be applied according
to the principles of adaptive management, resource-based and community-based, so that it can integrate science into decision-making
process, avoiding both narrow-minded viewpoints of planners and natural resource use conflicts among variety of stakeholders.
Problems to be resolved in the future are also pointed out in the ending part. 相似文献
994.
Carlos Navarro Florentino de Lope Anders Pape Møller 《Behavioral ecology and sociobiology》2007,61(8):1161-1168
Homeobox genes regulate development of digits, and it has been suggested that the ratio of length of second to length of fourth
digit reflects such genetic effects in a sex-specific manner. We show that digit ratios in the sexually dichromatic house
sparrow Passer domesticus differ between sexes, with males having higher ratios than females, and that individuals produce consistent ratios on the
two feet. If Homeobox or other genes had pleiotropic effects on development of digits, behavior, and physiology of males and
females, we would expect secondary sexual characters and immunity to be related to digit ratio in a sex-specific manner. The
size of the visible part of the black badge in February (a secondary sexual character), but not total badge size, was positively
correlated with digit ratios, suggesting that males with more male-like digit ratios had larger visible badges. Because of
sex-specific effects of development on secondary sexual characters and immunity, we predicted sex-specific differences in
immune response to be related to digit ratio. House sparrows with large digit ratios had weaker T cell-mediated immune response
than individuals with small digit ratios, particularly in females, implying that females with more male-like digit ratios
had weak immune responses. These findings are consistent with the hypothesis that early development, as reflected by digit
ratios, and genetics affect the expression of adult characters that are supposedly strongly contributing to fitness. 相似文献
995.
Richard A. Holland 《Behavioral ecology and sociobiology》2007,61(5):653-660
Bats have been extensively studied with regard to their ability to orient, navigate and hunt prey by means of echolocation,
but almost nothing is known about how they orient and navigate in situations such as migration and homing outside the range
of their echolocation system. As volant animals, bats face many of the same problems and challenges as birds. Migrating bats
must relocate summer and winter home ranges over distances as far as 2,000 km. Foraging bats must be able to relocate their
home roost if they range beyond a familiar area, and indeed circumstantial evidence suggests that these animals can home from
more than 600 km. However, an extensive research program on homing and navigation in bats halted in the early 1970s. The field
of bird navigation has advanced greatly since that time and many of the mechanisms that birds are known to use for navigation
were not known or widely accepted at this time. In this paper I discuss what is known about orientation and navigation in
bats and use bird navigation as a model for future research in bat navigation. Technology is advancing such that previous
difficulties in studying orientation in bats in the field can be overcome and so that the mechanisms of navigation in this
highly mobile animal can finally be elucidated. 相似文献
996.
Determining the scale of larval dispersal and population connectivity in demersal fishes is a major challenge in marine ecology.
Historically, considerations of larval dispersal have ignored the possible contributions of larval behaviour, but we show
here that even young, small larvae have swimming, orientation and vertical positioning capabilities that can strongly influence
dispersal outcomes. Using young (11–15 days), relatively poorly developed (8–10 mm), larvae of the pomacentrid damselfish,
Amblyglyphidodon curacao (identified using mitochondrial DNA), we studied behaviour relevant to dispersal in the laboratory and sea on windward and
leeward sides of Lizard Island, Great Barrier Reef. Behaviour varied little with size over the narrow size range examined.
Critical speed was 27.5 ± 1.0 cm s−1 (30.9 BL s−1), and in situ speed was 13.6 ± 0.6 cm s−1. Fastest individuals were 44.6 and 25.0 cm s−1, for critical and in situ speeds, respectively. In situ speed was about 50% of critical speed and equalled mean current speed.
Unfed larvae swam 172 ± 29 h at 8–10 cm s−1 (52.0 ± 8.6 km), and lost 25% wet weight over that time. Vertical distribution differed between locations: modal depth was
2.5–5.0 and 10.0–12.5 m at leeward and windward sites, respectively. Over 80% of 71 larvae observed in situ had directional
swimming trajectories. Larvae avoided NW bearings, with an overall mean SE swimming direction, regardless of the direction
to nearest settlement habitat. Larvae made smaller changes between sequential bearings of swimming direction when swimming
SE than in other directions, making it more likely they would continue to swim SE. When swimming NW, 62% of turns were left
(more than in other directions), which would quickly result in swimming direction changing away from NW. This demonstrates
the larvae knew the direction in which they were swimming and provides insight into how they achieved SE swimming direction.
Although the cues used for orientation are unclear, some possibilities seemingly can be eliminated. Thus, A. curacao larvae near Lizard Island, on average swam into the average current at a speed equivalent to it, could do this for many hours,
and chose different depths in different locations. These behaviours will strongly influence dispersal, and are similar to
behaviour of other settlement-stage pomacentrid larvae that are older and larger. 相似文献
997.
刘佳丽 《防灾科技学院学报》2010,12(3):48-54
2008年5月12日汶川8.0级地震的地震异常信息是否在我国现有的技术手段中有明显的异常体现,引起了人们的思考。本文用收集到的全国“十五”地热观测网中的190个地热前兆观测点的数据资料,对汶川8.0级地震的映震情况进行分析。结果30个观测点震前有前兆异常,86个观测点有同震响应及震后调整。其中有前兆异常的观测点仅占16%,震中距〈1100km出现前兆异常观测点占全部异常点(30个)的77%,占震中距〈1100km观测点(83个)的28%。由此分析了我国地热观测的现状及预测实践中存在的不足。例如观测孔勘选不理想有待筛选改进,数据资源私有应在全国及时实现资源共享等问题。 相似文献
998.
Catch and acoustic telemetry data were used to test three predictions of lekking behaviour in Atlantic cod (Gadus morhua L.) at a small-scale spawning ground (∼25 km2) in Placentia Bay, Newfoundland: (1) that cod form male-skewed aggregations during spawning; (2) spawning arenas occur at consistent sites; and (3) on the arenas, there will be higher proportions of spawning fish. Forty-two fishing sets from 1998 to 2003 indicated male-skewed sets early in the spawning season (April) in 5 of 6 survey years. Male-skewed sets were consistently distributed at depths < 50 m and mostly in one part of the ground. The proportions of spawning females and spent males were significantly higher in male-skewed sets, whereas sets with equal sex ratios had significantly higher proportions of immature males and spent females. In addition, cod of both sexes were significantly larger in male-skewed sets. Telemetric tracking of 25 cod in 2002 and 2003 (12 males, 13 females) indicated that both males and females were highly mobile while present on the spawning ground. Overall, our results add support to the hypothesis that cod employ a lekking mating system. 相似文献
999.
Lijuan Sun Cuixia Guo Ling Yao Tiejuan Zhang Jingjing Wang Li Wang Yan Liu Keyang Wang Longxia Wang Qingqing Wu 《黑龙江环境通报》2019,39(12):1086-1095
1000.