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61.
东北槭属的花粉形态及其在分类上的意义   总被引:2,自引:0,他引:2  
曹伟  卓丽环 《植物研究》1992,12(3):309-315
本文采用光学显微镜和扫描电镜,对我国东北地区械属10种变1种的花粉形态进行了观察。本属花粉近球形式长球形,赤道面观为近圆形或窄椭圆形,极面观为3裂圆形,极轴长2.-40μm;具3沟,沟明显;外壁通常具条纹状纹饰,稀具网状纹饰。从观察材料看,本属花粉可归之为2个类型:(1)色木槭型:(Mono maple type):外壁具条纹状纹饰,条纹宽0.250.50μm;(2)梣叶槭型(Ash-leaved maple type):外壁具条网状纹饰,网眼形状不规则,多为长形,长约3μm;网脊宽0.7μm,这正好与分类学家根据形态划分的个亚属相吻合。花粉形态所提供的资料,也支持色木槭(Acermono Maxim.)和平基槭(A.truncatum Bge.)作为两个独立种的处理意见。  相似文献   
62.
国产大戟属新资料   总被引:2,自引:0,他引:2  
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63.
Information about mosquito ecology in the high mountain ecosystems of the Neotropical region is sparse. In general, few genera and species have been reported in these ecosystems and there is no information available on habitats and the mosquitoes occupying them. In the present study, specimens collected from NW Colombia in HME were grouped using larval habitat data via an Operational Taxonomic Unit (OTU) determination. A total of 719 mosquitoes was analyzed belonging to 44 OTUs. The analysis considered habitat features and clustered the specimens into six groups from A‐F. Five of these included species from different genera, suggesting common habitat requirements. Group E with four genera, seven subgenera, and six species occupied the highest areas (above 3,000 m), whereas three groups (B, D, F) were detected at lower altitudes (1,960–2,002 m). Bromeliads were the most common larval habitat, with 47% (335/719) of the specimens; five genera, six subgenera, and eight species were identified and classified into 66% (29/44) of the OTUs. This work showed some similarities to the habitat requirements and provides a grouping system that constitutes an important baseline for the classification of mosquito fauna from high mountain ecosystems according to altitude and larval habitat.  相似文献   
64.
在光学显微镜和扫描电镜下观察了茄科酸浆属5种2变种及邻近属2种植物:辣椒和龙珠的叶表皮及种皮特征,发现上述植物的叶上、下表皮细胞表面观形状为不规则形,垂周壁浅波状、波状或深波状;一些类群的气孔器在上、下表皮均存在,另一些类群的气孔器则仅在下表皮存在,其类型一致为无规则型。扫描电镜下叶下表皮的特征,包括角质膜以及气孔外拱盖和拱盖内缘的特征,有一定的分类学价值。此外,种皮纹饰可作为区分酸浆属、辣椒和龙  相似文献   
65.
《Geobios》2016,49(5):407-422
Invertebrate fossils described from ancient hydrocarbon seep deposits represent diverse groups, e.g., brachiopods, mollusks, decapod crustaceans, worm tubes, and rare echinoderms, but the fossil record of ostracodes from hydrocarbon seep deposits is still very limited, making their ecology and evolutionary history still little known. We found fossil ostracodes in eight Eocene to Oligocene hydrocarbon seep deposits in the Humptulips, Lincoln Creek, Makah, and Pysht formations in western Washington State, USA. They represent eleven taxa belonging to genera found in a wide range of shelf to slope habitats: Acanthocythereis, Loxoconcha?, Cytherella, Cytheropteron, Macropyxis?, Krithe, Paracosta, Pontocythere?, Propontocypris, Palmoconcha, and Neonesidea? Acanthocythereis acroreticulata from one late Oligocene seep deposit in the Lincoln Creek Formation is the oldest and northernmost record for this species. The hydrocarbon seep ostracode faunas from Washington appear to be benthos-dominated, showing the same ecological structure and pattern of phylogenetic relatedness as ostracodes from Miocene and Quaternary seep sediments from Italy and off Ireland. We suggest that the benthos-dominated structure has been stable for ostracodes in hydrocarbon seep environments and/or has a higher preservation potential than the nektobenthos-dominated structure.  相似文献   
66.
在我国海域进行了很多自由生活线虫的研究,但是线虫分类学多样性的报道极少。2007年春季在天津海域的15个站位进行了底栖生物调查,对自由生活线虫样品进行了分类学多样性的分析。共鉴定出自由生活线虫87种,隶属于2纲2亚纲5目7亚目14科39属。以色矛纲(Chromadorea)线虫居多,有74种,占总种数的85%。线虫平均分类学差异性指数(Δ+)的理论平均值为60.5,分类学差异性变异(Λ+)的理论平均值约为420。平均分类学差异性指数值随站位而变,变化幅度为49.8~63.0;各站位分类学差异性变异的波动范围较大,从233到514不等。这些结果表明,线虫在一些站位的分类学信息有较大的不同。漏斗图显示,西南部近岸海域的线虫群落组成的分类学多样性较差,预示着环境受到干扰。线虫在西南部近岸4个站位的分类学差异性受到了化学因素的影响,多个化学指标具有较高值;同时也与沉积物的粒径和叶绿素含量有一定关系。与一些传统多样性指数比较,分类学差异性指数在反应环境差异方面有较好的灵敏性。  相似文献   
67.
68.
Correct spelling of taxon names in vegetation databases is a fundamental prerequisite for many data processing steps. However, manual detection and correction of spelling mistakes is inefficient, prone to errors and non‐reproducible, especially when scanning large databases. Here, I review six software tools that spell‐check taxon names in vegetation databases: (1) the Global Names Resolver, (2) the Interim Register of Marine and Nonmarine Genera, (3) the Taxonomic Name Resolution Service and R packages (4) Plantminer, (5) Taxonstand and (6) tpl. In particular, I test their capacity to spell‐check names across the taxonomic ranks and organism groups frequently encountered in vegetation data and challenge their ability to screen names from different geographic regions. Performance by software tools differed widely in these tests. Backed up by multiple reference lists, the Global Names Resolver emerged as the most versatile software tool. All software solutions currently suffer from some minor limitations, including an inability to spell‐check names of hybrid taxa. Furthermore, some spelling mistakes, by their nature, cannot be resolved unambiguously. Given these limitations, taxon names should be spell‐checked with software tools in a semi‐automatic rather than an automatic way.  相似文献   
69.
A nested sampling design was used to describe the spatial patterns for the species richness and composition in the seed bank and vegetation of three Mediterranean old-fields (1, 7, and 15 yr after the last ploughing). Three scales were examined hierarchically: sampling units within plots of 0.25 m2 for the vegetation and of 0.05 m2 for the seed bank, 100 m2 plots within fields, and fields of 1000 m2. In spite of the strong spatial variation among sampling units, species richness and composition of both seed bank and vegetation showed hierarchically structured patterns of heterogeneity, while each old-field was a homogeneous entity. These spatial patterns tended to be partially masked when the data were aggregated at the scale of the plot. Such results stress the use of a nested sampling design for studying variation in species richness and taxonomic composition in both vegetation and seed bank. This design, in combination with CCA, also showed that the vegetation showed a coarser grain than the seed bank, probably in relation to seed clumping.  相似文献   
70.
A review of the species and subspecies of Ditrema from East Asia recognized the following taxa: D. jordani Franz, 1910, D. temminckii pacificum subsp. nov., D. t. temminckii Bleeker, 1853, and D. viride Oshima, 1940. Ditrema jordani is characterized by a coppery-red body when fresh, the posterior end of the dorsal-fin base anterior to that of the anal-fin base, a dark rounded marking on the anterior suborbital area margined with white lines or a broad dark inverse trapezoid marking on the anterior part of the suborbital region, the lower half of the spinous portion of the dorsal fin often with a longitudinal black stripe, and a faint longitudinal dark line along the anal-fin base. Ditrema temminckii is characterized by a silvery body, usually bluish dorsally when fresh, a black oblique band on the anterior suborbital area, the spinous portion of the dorsal fin with a black distal margin, and no dark line along the anal-fin base. Ditrema t. pacificum, mainly distributed along the Pacific Ocean coast, differs from D. t. temminckii, mainly distributed along the coast of Sea of Japan, in lacking a dark spot on the anterior portion of the preopercle (vs. dark spot present in the latter), but having a black line along the posterior margin of the pelvic-fin spine (vs. black spot anteriorly on base of pelvic fin), fewer dorsal-fin spines (usually 9 or 10 vs. 10 or 11), more dorsal-fin soft rays (mode 21 vs. mode 20), and longer pectoral, pelvic, and caudal fins. The two nominal species (D. smitti and D. leave) are regarded as junior synonyms of D. t. temminckii. Ditrema viride is characterized by a silvery, dorsally yellowish-green body when fresh, 9–11 dorsal-fin spines (mode 10), a dark triangular marking on the anterior suborbital area, the spinous portion of the dorsal fin with a black distal margin, a longitudinal black line along the anal-fin base and the pelvic fin slightly darkish, and lacking a black spot anteriorly on the base. Neotypes are designated for D. jordani and D. viride. A key to the species and subspecies of Ditrema is provided.  相似文献   
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