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ABSTRACT Research to determine noise impacts on animals benefits from methodology that adequately describes the acoustical stimulus as well as the resulting biological responses. We present acoustical considerations and research techniques that we have found to be useful. These include acoustical definitions and noise measurement techniques that conform to standardized acoustical practice and advice for controlled experimentation to supplement behavioral observation. Specific considerations include characteristics of noise stimulus, selection of noise metrics, use of frequency-weighting algorithms tailored to a specific animal species, selection and placement of noise measurement equipment, and methods for documenting animal responses. We also present arguments for measuring the noise stimulus at the location and time of each response observation. Our purpose is to recommend some baseline terminology, metrics, and techniques prerequisite to effective assessment of noise impacts on terrestrial wildlife whenever and wherever potential conflicts arise.  相似文献   
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We have isolated 10 polymorphic microsatellite markers for the black‐bellied seedcracker (Pyrenestes ostrinus) from genomic libraries enriched either for (AAGG)n or (ATCT)n repetitive elements and characterized them in 39 individuals. The number of alleles ranged from two to 27 per locus with the observed heterozygosity ranging from 0.38 to 0.94. These markers will be useful for analysis of questions concerning parentage and population genetic structure.  相似文献   
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To determine the degree of genetic exchange between populations of the neon damselfish, Pomacentrus coelestis, among different reefs of the Great Barrier Reef, Australia, we characterized seven polymorphic microsatellite loci.  相似文献   
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It is shown that in susceptible barley DDT has a marked effecton cytochrome f responses, and on measurable levels of cytochromesb559LP, b559HP, and b6. These effects, not shown by treatedresistant barley, are discussed in the light of known sitesof inhibition by DDT of photosynthetic electron transport.  相似文献   
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To determine genetic substructuring in populations of the spiny damselfish Acanthochromis polyacanthus among different reefs of the Great Barrier Reef, Australia, we characterized six polymorphic microsatellite loci.  相似文献   
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We isolated 12 polymorphic microsatellite markers for the grey‐headed robin Poecilodryas albispecularis from genomic libraries enriched for (AAGG)n and (AACC)n repetitive elements and characterized them in 12 individuals. The number of alleles ranges from three to nine per locus with the observed heterozygosity ranging from 0.33 to 0.90. These markers will be useful for analysis of questions concerning population genetic structure and testing models of speciation.  相似文献   
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The effect of DDT in resistant and susceptible barley on variousphotosynthetic electron transport activities involving photosystems1 and 2 functioning alone and in series is reported. Whereasnone of the measured activities in resistant barleys were affectedby DDT treatment, in susceptible barley two sites of interactionof DDT with the photosynthetic electron transport chain weredemonstrated. The first site of inhibition was located beforephotosystem 2, between the sites of electron donation from diphenylcarbazideat pH 6·0 and 8·0, and on the oxidizing side ofthe inhibitions resulting from tris washing or heat treatment.Mn2+ ions, which can act as donor before photesystem 2, appearedto donate electrons on the H2O side of the site of inhibitionby DDT. The second site of DDT inhibition was located in thepath of electron flow from photosystem 2 to NADP+ or diquat,and was demonstrated by using dichlorophenolindophenol and phenylenediaminesas electron donors.  相似文献   
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Abstract: In 2006-2007, during Wasatch Powderbird Guides (WPG) permit renewal for heli-skiing in the Tri-Canyon Area (TCA) of the Wasatch Mountains, Utah, USA, we recorded 303 helicopter passes between 0 m and 3,000 m (horizontal distance) near ≥30 individual golden eagles (Aquila chrysaetos) in 22 nesting territories, through passive observation and active experimentation with civilian and military (Apache AH-64) helicopters. Flight profiles included 800-m, 400-m, 200-m, and 100-m flybys (horizontal distance from cliff nest on parallel course), as well as approaches and popouts where helicopters flew toward, or popped out from behind, adult-occupied cliff nests (0 m, horizontal distance). Between 1981 and 2007, during the only 8 years when nesting in the TCA was confirmed by presence of chicks, WPG annually flew 108–2,836 helicopter flights in the same drainages on 10–37 days between 15 December and 15 April, with no effect on early courtship, nest repair, or subsequent nesting success. Total WPG operating days (x̄ = 62.4) and helicopter hours (x̄ = 210.6) fluctuated annually but did not increase 1974–2007 (Cox-Stuart trend test, P = 0.371, 0.393, respectively). Apache helicopter testing (227 passes) did not reduce golden eagle nesting success or productivity rates within the same year (t111, 96 = 0.495, 0.782, P = 0.622, 0.436, respectively), or rates of renewed nesting activity the following year, compared with 81–101 non-manipulated nesting territories. We recorded no response during 66% and only watching during 30% of Apache passes at 0-800 m from nesting golden eagles. No other reactions occurred until after hatching when ≤4 golden eagles accounted for 5 flatten and 3 fly behaviors at 3 nest sites. No responding pairs failed to fledge young because of testing. Limited fly responses suggested helicopters only precipitated an imminent departure, rather than causing startled, avoidance reactions. Responsiveness between test weeks 1 and 2 decreased (X22 = 32.167, P ≤ 0.001). Apache helicopters were twice as loud as WPG helicopters at comparable distances. Sound decreased with distance, most rapidly when flights were perpendicular to cliffs or ridges. Eagle ambient behaviors and watching the helicopter occurred randomly throughout recorded sound levels during helicopter testing (76.7–108.8 decibels, unweighted). Much helicopter sound energy is below golden eagles' auditory threshold, thus reducing potential impacts. Neither our observations nor our testing indicated special management restrictions are required for helicopters flying near nesting golden eagles in northern Utah. Our results underscore the necessity for circumstance-specific research, as well as enlightened resource management to accommodate unexpected results.  相似文献   
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