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1.
中国科学院海洋研究所建所70年来,在海洋贝类分类学研究领域取得了长足发展与进步,做出一系列开创性研究成果。本文综述了建所以来我所海洋腹足类分类学研究方面的主要进展,概述了取得的主要科研成果,分析了现代腹足类分类学研究的发展趋势以及面临的挑战,并对今后的发展提出了相应对策和建议。  相似文献   
2.
海产腹足类有机锡化合物的检测方法   总被引:3,自引:0,他引:3  
黄长江  雷瓒  董巧香 《海洋学报》2005,27(4):174-180
三丁基锡(TBT)等有机锡化合物因其毒性及结构上的特点被广泛应用于船舶、网箱渔排等的防污涂料中.它的主要作用是在水体中持久地释放出可以有效杀死海洋污损生物的毒性物质,从而达到防护船舶、渔排等体表的目的[1],然而进入海洋环境的有机锡化合物在防污的同时也会影响到许多非靶生物,并对海洋生态系统的结构与功能产生严重的危害,被认为是迄今为止人为引入海洋环境毒性最大的物质之一[2~4].因此,检测海洋生物体内的有机锡含量成为对有机锡污染生态效应调查与研究不可缺少的手段[5~7].  相似文献   
3.
Variations in environmental factors can alter the species distribution pattern in intertidal rocky shores. The Persian Gulf (PG) and the Gulf of Oman (GO) vary substantially with respect to environmental and oceanographic conditions. The abundance and biodiversity of intertidal rocky gastropods in five locations across the northern PG and the GO were compared, and the environmental variables underlying the distribution pattern of these organisms were investigated. A total of 67 gastropod species were identified. The largest average density (294 ind./m2) and diversity (N = 43) for gastropods occurred in the Hotel Lipar station (LIP) located in Chabahar Bay in the GO. Clypeomorus bifasciata (107.43 ind./m2) followed by Cerithium caeruleum (94.67 ind./m2) were the most abundant species. Planaxis sulcatus and Siphonaria spp. occurred in all locations during both sampling occasions. Species richness and abundance of gastropods showed significant differences between LIP and remaining locations. A significant difference was found in assemblage structure across locations. In general, the species richness and density in the locations at GO were significantly larger than those locations in the PG, suggesting that the harsh environmental condition in the PG might be the forcing factor for this diminish. Distinct grouping was observed in both assemblage structure and species composition between locations in the PG and the GO. The spatial and temporal distribution patterns of gastropods assemblages were significantly correlated with variation in salinity and substrate rugosity.  相似文献   
4.
采自西藏阿里地区五县市几个层位的腹足类化石分属早奥陶世、早石炭世、早二叠世、早白垩世(多数)、晚白垩世(少数)及第三纪等时限;共计31种(包括12个新种、3个相似种、8个未定种),归入26属(包括1新属),分属14科。它们的地理分布及与它区的对比也略予论述。  相似文献   
5.
Bathymetric patterns of macrofaunal species diversity are best documented in the western North Atlantic where diversity is a unimodal function of depth, peaking in the mid-bathyal zone and being depressed in the upper slope and abyss. There are few inter-basin studies of diversity-depth trends that are controlled for taxonomy, sampling gear, and diversity measures. In this paper, we compare gastropod diversity gradients in the North American Basin of the Atlantic to estimates of diversity in 9 other regions: the Norwegian Sea, West European Basin, Guiana Basin, Gambia Basin, Equatorial Mid-Atlantic, Brazil Basin, Angola Basin, Cape Basin and Argentine Basin. All samples were collected with epibenthic sleds, and diversity calculated by the Sanders-Hurlbert normalized expected number of species. While sampling in other regions is generally less complete than in the western North Atlantic, results indicate that a unimodal pattern is not universal. Diversity can increase, decrease or show no relationship with depth. The level of diversity also varies among basins relative to the western North Atlantic, being depressed in the Norwegian Sea, at bathyal depths in the eastern North Atlantic, and below an oxygen minimum zone in the Cape Basin, and generally elevated at tropical latitudes and in abyssal regions where food supply is high. Associations between gastropod diversity and the ecology and geology of basins suggest that productivity, oxygen concentration, hydrographic disturbance and evolutionary-historical processes may be implicated in shaping bathymetric diversity gradients, but specific causes are difficult to discern. Much more intensive sampling, analyses of other major taxa, and more detailed ecological data are necessary to understand deep-sea biogeography at within- and between-basin spatial scales.  相似文献   
6.
首次报道了广东饶平海山区腹足类。经整理和分类研究,共鉴定出腹足类16科25属30种。这些种均为现生分布种,主要分布在中国沿海,特别是浙江以南海区,少数分布在黄海较北部海区。大多数种类栖息于低潮线至浅海几十米水深的沙泥质或泥沙质海底,也出现一些潮间带岩礁栖息型种类。可能反映了具较高海水能量的浅水沉积环境。根据动物群的组合特征,它们应为第四纪全新世的产物。  相似文献   
7.
8.
黔北桐梓红花园地区的五峰组是华南地区奥陶系的重要剖面之一,在其以泥质灰岩为特征的五峰组观音桥段下部黑色含炭质钙质页岩和褐色粉砂岩中分别产有较为丰富的双壳类Modiolopsis和腹足类Holopea。产双壳和腹足类的地层中岩性和生物具有差异性,表明观音桥段沉积早期的沉积环境具有多变的特征。横长卵形、较膨凸的Modiolopsis和其两瓣壳相连保存的标本表明为近原地埋藏,为弱水动力、有氧的、较浅水环境的软质基底。丰度较大的低圆锥形Holopea的不规则的壳顶指向指示了具一定水动力的、沙性基底的浅水环境。  相似文献   
9.
Reef landscapes dominated by canopy-forming species are often irregular mosaics of habitats, with important influences on associated fauna. This study tested if differences in the ecological patterns of mobile fauna inhabiting interspersed (morphologically distinct) algal habitats were altered by the spatial arrangement of reefs of varying proximity to the shoreline. Specifically, prosobranch gastropods were used as models to test that: (1) there were differences in the ecological patterns (species composition and abundances) between three algal habitats (the kelp Ecklonia radiata, fucalean macroalgae, and erect red algae); (2) the magnitude of these differences depended on the position of reef lines (‘in-shore’ vs. ‘off-shore’); and (3) these effects were regionally consistent across a 4° latitudinal gradient (600 km of coastline) in Western Australia. The ecological patterns of algal-associated gastropods responded strongly to the presence of algal habitats with different physical structure at small spatial scales. Importantly, differences in assemblage structure (e.g. differences in total abundances) between habitats across the latitudinal gradient were especially accentuated on the in-shore reefs compared with the off-shore reefs, where a general amelioration of differences between habitats was observed, probably associated with a more widespread effect of stronger wave forces across habitats. Overall, red algae supported higher total abundances and species richness (per algal weight) compared to the other algal habitats, particularly on in-shore reefs. Patterns for individual species were considerably location-dependent, reflecting the natural variability of species across geographical gradients. In contrast, patterns at the assemblage-level were consistent, providing evidence for the existence of general rules underlying the assemblage-level organization of mobile invertebrates on subtidal reefs across this geographical gradient.  相似文献   
10.
The Rocks loess section, in unglaciated western Kentucky, provides a high-resolution environmental record during the last glacial maximum onset. The Peoria Silt (9 m thick) contains 26 terrestrial gastropod species, with up to 15 species within a single 5 cm interval. Thirteen radiocarbon ages, using shells or charcoal, range between 30 and 24.5 cal ka; younger loess has been leached or eroded. Stratigraphic shifts in gastropod assemblages imply significant cooling, particularly ~27 cal ka, as solar insolation was decreasing and the southern Laurentide Ice Sheet rapidly advancing. Midwestern to southern species (e.g. Anguispira kochi, Gastrocopta pentodon, Hawaii miniscula, Helicodiscus parallelus, Vallonia perspectiva) occur only in the lowermost Peoria Silt (~30–27 cal ka). In contrast, cold-tolerant species (Columella alticola, Vertigo modesta, Vallonia gracilicosta) occur only in full glacial Peoria Silt (27–24.5 cal ka). Inferred mean July temperatures, from mutual climatic range methods, range from ~23 °C at 30 cal ka, cooling to ~18 °C by 26 cal ka; about 3–8 °C cooler than today (~26 °C). Superimposed on this cooling trend are multi-centennial variations in detrital carbonate, fossil shell concentrations, palaeotemperature estimates, and oxygen isotope values (Vertigo, Discus, Helicodiscus). The finer-scale variations imply relatively synchronous fluctuations in glacial sediment supply, loess sedimentation, and climate.  相似文献   
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