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71.
Marine mollusks are among the most importantinvertebrate fisheries in the world. The mainclasses of mollusk fished are Cephalopoda,Bivalvia and Gastropoda. Marine gastropodsrepresent approximately 2% of the mollusksfished in the world. Several species ofgastropods, such as Haliotis spp., Strombus spp., Busycon spp. and Concholepas concholepas, have high economicvalue in international markets and playimportant social roles in small-scale artisanalfisheries. In the past 25 years wild-stockcatches of marine gastropods have increasedfrom 75,000 mt in 1979 to 103,000 mt in 1996.During the same period the countries involvedin gastropod landings rose from 23 to 47.Gastropods are fished mainly in: (1) theAmerican continent, dominated by the extractionof the muricid ``loco', C. concholepas, inChile and Peru; strombid conchs, Strombusspp., in the Caribbean, and abalone, Haliotis spp., in California and the west coastof the Baja California peninsula; (2) Asia andOceania, with the dominate abalone fishery,mainly in Australia and New Zealand, and thehorned turban snail, Turbo truncatus, inJapan and Korea; (3) in Africa and Europe, thedominate species extracted are Haliotismidae, heavily fished in South Africa, and thecommon periwinkle, Littorina littorea,and the whelk Buccinum undatum, which areextracted in Europe. This review summarizes the fishery of abalonespecies in California and the west coast of theBaja California peninsula. We highlightoverfishing situations and the utilization ofadaptive management tools, such as those inoperation in Baja California, where small-scalefisher associations (cooperatives) havereceived exclusive access rights to abaloneextraction within specific fishing zones, since1936. We also review the abalone fishery inAustralia, and the use of IndividualTransferable Quotas (ITQs) and Total AllowableCommercial Catches (TACC), which have been inuse since the mid-1980's. We describe thegastropod fisheries in Chile, mainly C. concholepas, highlighting their economic andsocial importance. We provide information onthe evolution of catches and exports anddiscuss the development of novel managementadaptive tools, such as the implementation ofthe Benthic Regime for Extraction andProcessing (BREP), the introduction ofNon-Transferable Individual Quotas (NTIQs) andterritorial users rights for benthic fisheries,such as the Management and Exploitation Areas(MEAS). Finally, we present and discuss thenecessary steps for the sustainable managementof marine gastropods and other benthic resources. 相似文献
72.
Abstract
- 1 Objectives of this study were to examine (i) between‐provenance variation in susceptibility to insects in Eucalyptus globulus and (ii) relationships between insect damage and tree growth. We planted seedlings of 18 provenances of E. globulus from south‐east Australia in a field trial and measured tree growth and insect damage.
- 2 Christmas beetles Anoplognathus spp. were the dominant herbivores during this experiment, and 99% of trees were affected by them. Defoliation of individual trees by Anoplognathus spp. ranged from 0% to 85%.
- 3 The main results of this study were that: (i) provenances of E. globulus from Tasmania and the Bass Strait islands, which had previously shown resistance to autumn gum moth Mnesampela privata and leaf blister sawfly Phylacteophaga froggatti tended to be resistant to Anoplognathus spp.; (ii) mean tree volume was reduced by herbivory; and (iii) the volume‐based performance ranking of provenances changed depending on the probability of insect outbreaks.
- 4 Fast‐growing provenances should be planted in optimal growing areas for E. globulus with low probability of insect outbreaks. However, in suboptimal growing areas, planting slightly slower growing but more resistant provenances is likely to result in greater output than planting fast‐growing provenances when the probability of insect outbreaks is high.
73.
A new hairtail, Trichiurus nickolensis, is described on the basis of ten specimens collected off northwestern Australia, off the Northern Territory, and in the Gulf of Carpentaria, Queensland. The new species strongly resembles T. brevis Wang and You in Wang et al., 1992, off Hainan Island, South China Sea, and T. russelli Dutt and Thankam, 1966, off the Waltair Coast, Andhra Pradesh, India, in having the highest point of the supraoccipital crest situated directly above the posterior margin of the eye and a relatively short caudal peduncle. Trichiurus nickolensis differs from those two species in being strongly pigmented on the anterior section of the dorsal fin membrane (vs. slightly pigmented), and having a dorsal head margin that appears concave in lateral view, rises gently from snout tip to above middle of orbit, and then extends more steeply to dorsal fin origin (vs. rising gently from tip of snout to dorsal fin origin). The new species also has a greater number of dorsal fin rays (III, 138–143 vs. III, 127–132 and III, 127–131 in T. brevis and T. russelli, respectively) and total vertebrae (160–166 vs. 147–155 and 149–153), and shorter preanal length (mean 30% TL vs. 33% TL and 35% TL), head length (11% TL vs. 12% TL and 13% TL) and upper jaw length (4% TL vs. 5% TL and 5% TL). 相似文献
74.
Many forensically important calliphorids, sarcophagids and muscids (Diptera) oviposit or larviposit on corpses only during the early stages of decomposition, yet individuals may attend bodies throughout decay. A field study was conducted to investigate how patterns of carcass use and attendance by some fly species are affected by decomposition. Five fly traps were placed in the forest and baited with whole, fresh piglet carcasses. Piglets decomposed in traps throughout the experiment, and all were skeletonized within 6 days. Flies were trapped at both early and late decomposition stages, and the species and population structures of trap catches were compared. More flies attended carcasses early rather than late in decay. For all species, flies attending early were mainly gravid females, but few gravid females attended late in decay. No females ovi- or larviposited late in decay, whereas females of all fly species deposited offspring early in decay. The number of males trapped of each species correlated positively with the number of females with eggs at early development stages. Observations were made of fly predation by European wasps Vespula germanica Fabricius (Hymenoptera, Vespidae) and jumper ants Myrmecia pilosula Smith (Hymenoptera, Formicidae) throughout the experiment. There was a higher risk for smaller fly species of being killed following predator attack. Ants and wasps attacked smaller fly species, whereas only wasps attacked larger fly species. 相似文献
75.
Johansen CA Farrow RA Morrisen A Foley P Bellis G Van Den Hurk AF Montgomery B Mackenzie JS Ritchie SA 《Medical and veterinary entomology》2003,17(1):102-111
Circumstantial evidence has implicated wind-borne mosquitoes (Diptera: Culicidae) in the introduction of Japanese encephalitis (JE) virus into Australia from the New Guinea mainland. A study was initiated on Saibai Island in the northern Torres Strait, during January and February 2000, to identify the potential source of insects collected in aerial (kytoon) and surface-level traps. Wind speed and direction were recorded to determine wind profiles during insect sampling. Northerly winds capable of carrying insects from New Guinea to Saibai Island were only present on three out of 18 nights sampled. Only three male mosquitoes, comprising two Verrallina funerea (Theobald) and one Ochlerotatus vigilax (Skuse), were collected in aerial samples, and were most likely of local origin. Culicoides midges were also collected in aerial nets and included gravid/parous C. bundyensis Lee and Reye, and one parous C. histrio Johannsen. Highest densities of arthropods (up to 1562/million m3) were on 30 January 2000 when NW winds, sustained for six hours, probably introduced midges from the New Guinea mainland. Adult mosquitoes (including three female Ve. funerea and a single female Ficalbia) and Culicoides (including two gravid C. bundyensis and one parous C. cordiger Macfie) were also collected in 2 m high mast nets during northerly surface winds. Although the results do not provide evidence that wind-blown mosquitoes introduced JE from New Guinea into Australia, they do not preclude that strong N winds associated with low pressure systems SW of the Torres Strait could have done so. However, results suggest that Culicoides were more likely than mosquitoes to reach high altitude and travel long distances during the light N winds experienced during the study. 相似文献
76.
Abstract Semiocladius Sublette and Wirth, described from adult midges from south-western Pacific Ocean shores, has the Australian Camptocladius crassipennis Skuse as its type. Immature stages previously known only from Semiocladius kuscheli Sublette and Wirth from sub-Antarctic New Zealand were associated tentatively, by co-occurrence. For the first time, the immature stages for the Australian species are associated definitively by rearing. Larvae rear to a pupa identical to a speculatively associated exuviae of Semiocladius from Lord Howe Island. Adults conform to the described S. crassipennis . Larval Semiocladius are distinctive and previous diagnoses are confirmed. In contrast, the putatively associated pupa of S. kuscheli is indistinguishable from that of the marine intertidal Thalassosmittia Strenke and Remmert, whereas the newly associated S. crassipennis pupa is distinct. The pupa of S. kuscheli may have been misassociated. Semiocladius live in the mesohaline of the salinity gradient of the Clyde River estuary, south-east Australia and the genus appears to be a distinctive western Pacific saline/mesohaline taxon. 相似文献
77.
Patterns of distribution of macroinvertebrate families in rivers of north-western Australia 总被引:1,自引:0,他引:1
W. R. Kay† M. J. Smith A. M. Pinder J. M. Mcrae J. A. Davis† S. A. Halse 《Freshwater Biology》1999,41(2):299-316
1. The northern half of Western Australia is a large, sparsely populated area with a climate that ranges from monsoonal in the Kimberley to arid in the Gascoyne and Pilbara regions. The aquatic invertebrate fauna is poorly known. 2. Fifty-one sites located on 14 river systems were sampled three times between August 1994 and October 1995. A total of 90 taxa, most identified to family level, were collected. The fauna was dominated by insects, which constituted 74% of the total number of taxa collected. 3. Major habitats at each site were sampled separately and sites with more habitats tended to have a richer fauna. All habitats showed significant differences in taxonomic richness between regions. Family richness decreased with increasing latitude, being highest in the Kimberley region and lowest in the Gascoyne. 4. Despite the differences in taxon richness between regions, community composition of the aquatic invertebrate fauna at the family level did not differ greatly. Four major groups of sites were identified by cluster analysis, based on the invertebrate families present at each site, but differences between groups were small. 5. Significant temporal variation in taxon richness was found in channel habitat but not the three other habitats sampled (riffle, macrophyte, pool-rocks). Community composition in channel habitat varied temporally among groups of sites identified by cluster analysis but the pattern was not consistent. 相似文献
78.
Reproduction and life history patterns in culture of five Caloglossa speaes from Australia and New Zealand are compared. Caloglossa adhaerens King et Puttock and Caloglossa bengalensis (Martens) King et Puttock have a Polyslphonla‐type sexual life history (P‐type, isomorphic alternation of generations). Caloglossa monosticha Kamiya occurs only in Western Australia (WA) and is a P‐type. Caloglossa ogasawaraensis Okamura occurs in WA, Northern Territory (NT), Queensland (QLD), New South Wales (NSW), Victoria (VIC) and South Australia (SA) and is for the most part a P‐type in culture. A few isolates have bisexual gametophytes that are self‐compatible, while most are unisexual. Caloglossa ogasawaraensis from Adelaide, SA and from Wilsons Promontory, VIC are new records for these States. In Australia, Caloglossa postiae (King et Puttock) Kamiya et King occurs in NSW, NT and QLD. All nine isolates are P‐type. Isolates of Caloglossa leprieurii (Montagne) G. Martens from NSW, NT, QLD, Tasmania, VIC and New Zealand are P‐type except for the freshwater isolates in which tetraspore germlings do not reproduce. In some isolates mixed‐phase reproduction is seen with male gametophytes producing both viable spermatia and tetrasporangia and female gametophytes producing procarps and sori with non‐dividing sporangia. All isolates of C. leprieurii irom Spencer Gulf and Gulf of St Vincent, SA and one isolate from QLD give rise to successive asexual generations of tetrasporophytes. Based on RuBisCO spacer DNA data an asexual life history has arisen several times in the C. leprieurii complex. The literature on apomixis, mixed‐phase reproduction, bisexuality and sexual compatibility in red algae is surveyed. 相似文献
79.
80.
Andrew Merchant Pauline Y. Ladiges Mark A. Adams 《Global Ecology and Biogeography》2007,16(6):810-819
Aim Increasing aridity over geological time-scales has driven a high degree of speciation within the Eucalyptus group in Australia. Isolation of gene pools by climatic and edaphic conditions and high rates of out-crossing have given rise to a large diversity of adaptive traits. Among these traits, adaptations of cellular biochemistry are likely to be significant in preserving cellular function during arid conditions. The aim of this study was to determine the quantitative and qualitative distribution of soluble carbohydrates and polyols in Eucalyptus .
Location Australia.
Methods We sampled 279 of the 700+ documented eucalypts (in the three genera comprising the eucalypts: Angophora Cav., Corymbia Hill & Johnson and Eucalyptus L'Hér.) and analysed leaf tissues for the occurrence of low-molecular-weight carbohydrates and polyols.
Results We have uncovered a discrete pattern in concentration of quercitol (a cyclitol) that correlates strongly with the current taxonomic classification based on both morphology and DNA sequencing. We also uncovered a further and stronger correlation between the presence of quercitol in leaf tissues and a reduced growth (mallee) form.
Main conclusions These findings, together with the chemical properties of quercitol, suggest that we have uncovered a chemical marker of structural adaptations to arid conditions, thus providing a putative, broad-scale functional link to adaptation to aridity. 相似文献
Location Australia.
Methods We sampled 279 of the 700+ documented eucalypts (in the three genera comprising the eucalypts: Angophora Cav., Corymbia Hill & Johnson and Eucalyptus L'Hér.) and analysed leaf tissues for the occurrence of low-molecular-weight carbohydrates and polyols.
Results We have uncovered a discrete pattern in concentration of quercitol (a cyclitol) that correlates strongly with the current taxonomic classification based on both morphology and DNA sequencing. We also uncovered a further and stronger correlation between the presence of quercitol in leaf tissues and a reduced growth (mallee) form.
Main conclusions These findings, together with the chemical properties of quercitol, suggest that we have uncovered a chemical marker of structural adaptations to arid conditions, thus providing a putative, broad-scale functional link to adaptation to aridity. 相似文献