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901.
EcologicalstudyonOstracodainthecentralSouthChinaSea¥ChenRuixiangandLinJinhong(ThirdInstituteofOceanograply,StateOceanicAdmini... 相似文献
902.
Abstract. The polychaete fauna of the subtidal in the médiolittoral and the infralittoral hard bottom zones of the Balearic Islands at depths from 0 to 40m contained 220 species. Five different polychaete communities could be identified by changes in abundance, species richness, species composition, diversity, and trophic structure. In the very clear waters of these islands the infralittoral zone extends to a depth of 40 m and allows us to investigate whether former proposed models of polychaete distribution can be extended to this particular situation. 相似文献
903.
Abstract. Distribution patterns of epiphytic hydroids of seagrass ( Posidonia occanica and Cymodocea nodosa ) beds were studied in the 'Stagnone', a moderately hypcrhaline lagoon in Sicily. The role of water movement in determining the spatial and temporal zonation of epiphytic hydroids and their morpho-physiological variations is evaluated. Remarks on systematics arc also included. 相似文献
904.
长江口中肋骨条藻赤潮发生全过程调查报告
──浮游植物群落结构及细胞形态研究
总被引:6,自引:0,他引:6于1990年6月在长江口赤潮多发区定点观测到一次中肋骨条藻赤潮发生的全过程,对中肋骨条藻赤潮发生过程中浮游植物群落结构的变动及细胞形态的变化进行研究。结果表明,(1)中肋骨条藻赤潮发生前,水体中甲藻数量多于硅藻;赤潮发生后,中肋骨条藻增殖,逐渐成为主要优势种,硅藻在数量上超过了甲藻;浮游植物种类丰度指数的大小能较好地反映赤潮发生的各个阶段。(2)赤潮发生过程中,中肋骨条藻细胞增殖率次序为:发展阶段>维持阶段>起始阶段。(3)在赤潮发生的维持阶段后期和消亡阶段,有5%-7.8%的中肋骨条藻形成休眠孢子,一个中肋骨条藻细胞仅形成一个休眠孢子,且同一个中肋骨条藻群体链上的所有细胞形成休眠孢子是同步的。 相似文献
905.
906.
Amanda E. Valois Juliet R. Milne Mark W. Heath Rob J. Davies-Colley Emily Martin Rebecca Stott 《新西兰海洋与淡水研究杂志》2020,54(2):200-217
ABSTRACT Water is an important component of many recreational opportunities and New Zealand invests significant resources in recreational water quality (RWQ) monitoring to assess risks to public health. However, monitoring primarily focuses on microbiological hazards and RWQ is considerably broader than this. The goal of this study was to take a comprehensive approach to evaluating RWQ while exploring the potential for greater public involvement in monitoring. A popular river swimming site was co-monitored weekly by volunteers and a council field officer. The attributes monitored–water temperature, visual clarity, benthic cyanobacteria and filamentous periphyton cover, E. coli and rubbish–were identified from a volunteer workshop. There was good concordance between volunteer and council data suggesting that volunteer measurements can be considered reliable. This highlights the potential for volunteers, with professional support, including training and quality assurance, to extend council RWQ surveillance to additional monitoring sites while improving public engagement on water management. 相似文献
907.
908.
Effects of Soft Corals on Scleractinian Coral Recruitment. II: Allelopathy, Spat Survivorship and Reef Community Structure 总被引:1,自引:0,他引:1
Abstract. Two field experiments were performed on the Great Barrier Reef, Australia, at Orpheus Island and Lizard Island, respectively, to investigate the effects of allelopathic soft corals on survivorship and community structure of scleractinian coral spat. Ceramic tiles were placed around the allelopathic soft corals Sinularia flexibilis (Quoy & Gaimard 1833) and Sarcophyton glaucum (Quoy & Gaimard 1833), and controls. One control consisted of settlement plates surrounding a scleractinian coral (non‐allelopathic planktivore); another control had no adult soft or scleractinian coral present. The experimental soft corals affected the recruitment of various taxonomic groups of coral spat differentially, as evidenced by the diversity of coral spat settling in treatments and controls. At Orpheus Island (O.I., n = 1038 spat) and Lizard Island (L.I., n = 7032 spat), there were significant differences between recruitment success of the two dominant coral taxa, Pocilloporidae (O.I., 61.4 %; L.I., 20.5 %) and Acroporidae (O.I., 33.7 %; L.I., 53 %). Settlement plates exposed to Sinularia flexibilis at either site had the lowest proportion of acroporid recruits. Diversity indices (Shannon‐Wiener Indices) varied significantly between treatments at both Orpheus and Lizard Islands. This appears to be due to selective inhibition of acroporid spat by Sinularia flexibilis at both sites. Growth of coral spat was higher on settlement plates in the presence of Sarcophyton at Lizard Island. Settlement of most associated epibiota was generally inhibited under these conditions. Coral spat survivorship was highest in the presence of Sinularia at Orpheus Island; at Lizard Island, this was the case with the Sarcophyton treatment. Higher survivorship, and in some cases growth, of coral spat near soft corals was apparently due to reduced competition for space between spat and associated epibiota. This hypothesis is supported by the results of a sister experiment where a coating of Sinularia flexibilis extract on settlement tiles significantly decreased fouling by sessile epibiota. Soft corals have an allelopathic effect on recruitment and early development of scleractinian corals and, consequently, on early coral reef community succession. 相似文献
909.
Abstract. The polychaete community structure from six Halodule wrightii seagrass beds along the Rio de Janeiro coast (Southeast Brazil) was investigated. Variations in species diversity, overall density and species composition in relation to sediment grain size, seagrass biomass and selected plant structural features such as root and shoot length from the study sites were analysed. Ten core samples (0.02 m2 ) were randomly collected from each site. Three additional samples were taken for grain size analysis of sediment. Sixty-eight species of polychaetes belonging to 24 families were found. The dominant species as well as species composition varied greatly among sites, showing that a typical polychaete community does not exist. The number of species was positively correlated with the silt-clay percent and sorting coefficient of the sediment. A positive correlation between polychaete density and plant biomass was also obtained. Multivariate analysis indicated that polychaete communities were influenced greatly by seagrass plant features: plants with longer shoots harbour mainly surface-deposit feeders such as Magelona papillicornis , whereas plants with a higher root-shoot length relation sheltered mainly suspension or interface feeders like Fabricia filamentosa . This study demonstrates that granulometric properties as well as plant architecture play an important role in structuring the polychaete community. As the community-level response can reflect changes in local seagrass beds, the structure of the polychaete community can be an important indicator for management plans and the restoration of seagrass ecosystems. 相似文献
910.
基于2018年5月胶州湾海域共计20个站位所获取的生物及环境数据,研究胶州湾大型底栖生物多样性以及群落结构特征。调查海域共发现大型底栖生物208种,大型底栖生物总平均丰度和生物量分别为2 654.38 ind./m2和1 024.512 2 g/m2,大型底栖生物物种数、丰度和生物量均呈现北部高、南部低的分布趋势;调查海域优势种以多毛类为主,IRI值最高的物种为菲律宾蛤仔Ruditapes philippinarum;香农维纳指数与ABC曲线均表明调查海域底栖生态环境整体清洁;在40%相似性水平上,可将调查海域大型底栖生物划分为4个群落;底温和底盐影响调查海域大型底栖生物丰度分布。 相似文献