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91.
随着世界各国对能源安全、生态环境、气候变化等问题日益重视,加快发展风电已成为国际社会推动能源转型发展、应对全球气候变化的普遍共识和一致行动。过去十余年,我国海上风电产业受益于国家政策的大力推动而蓬勃发展,大有乘势崛起,赶超其他清洁能源的势头。相比陆上风电场,海上风电场对环境的影响较小,但其开发实施以及运行对海洋生态环境和资源开发的累积影响还尚不明确。本文系统全面地梳理了海上风电工程对鸟类、鱼类、海洋哺乳动物、底栖生物、浮游生物及海洋生物多样性等影响的研究进展,总结了海上风电环境影响研究的现状。结合我国实际,提出了将科学研究与海上风电工程环境影响评价紧密结合,开展海上风电项目对区域生态环境影响的研究等有关建议。 相似文献
92.
Abstract. Density of barnacle larvae in plankton and settlement on atoxic plane surfaces have been compared at one station of Genoa harbour over sixteen months.
There were two periods of larval emission, during summer and autumn, with a slight one during winter. Barnacle settlement varied according to sea temperature, the amount of larvae and competition for the substratum. 相似文献
There were two periods of larval emission, during summer and autumn, with a slight one during winter. Barnacle settlement varied according to sea temperature, the amount of larvae and competition for the substratum. 相似文献
93.
94.
沙坡头人工固沙植被演替过程中主要结皮生物生态位和种间关联变化特征 总被引:1,自引:1,他引:0
为探究干旱沙区人工固沙植被演替过程中结皮生物的种间关系变化规律,利用空间代替时间的方法,调查了宁夏沙坡头地区分别始建于1956、1964、1981、1987年人工固沙植被区(分别代表固沙植被建立后的64、56、39、33年4个演替阶段)中发育的6种典型结皮生物——蓝藻(Cyanobacteria)、球胶衣(Collema coccophorum)、石果衣(Endocarpon pusillum)、真藓(Bryum argenteum)、土生对齿藓(Didymodon vinealis)和齿肋赤藓(Syntrichia caninervis)的盖度及频度变化,并以不同样方作为资源状态计算其生态位宽度和重叠值,随后利用方差比率法、卡方检验和种间关联系数分析了它们在固沙植被演替过程中种间关联性变化规律。结果表明:(1)随着固沙植被演替,结皮生物的生态位宽度与重叠指数因具体结皮生物的不同而显现出显著差异:蓝藻生态位宽度迅速变窄(由演替33年的3.865降到演替64年的0),且与其他结皮生物之间生态位重叠值逐渐降低;真藓与球胶衣生态位宽度基本保持不变且高于其他类型,且二者保持较高生态位重叠;土生对齿藓、齿肋赤藓和石果衣生态位宽度在固沙植被演替前期较小,但随着固沙植被演替的进行明显上升(分别由演替33年1.607、0和0.693上升到演替64年的3.699、3.227和3.373),三者间生态位重叠值也随之提高。(2)结皮生物的种间总体关联性随着固沙植被演替由负关联向正关联转变,在演替64年时达到最大值(VR=1.15);不同结皮生物间联系随着固沙植被演替逐渐增强,地表隐花植物群落结构和种类组成趋于稳定。本研究不仅为揭示干旱沙区结皮生物的相互作用、共生共存及演变机制提供了依据,而且对以结皮生物作为新型固沙材料及相关技术的研发具有重要的参考价值。 相似文献
95.
Laurel A. Zahn Jeremy T. Claisse Jonathan P. Williams Chelsea M. Williams Daniel J. Pondella II 《Marine Ecology》2016,37(4):770-785
Understanding species distributions and their community structure is increasingly important when taking an ecosystem‐based approach to conservation and management. However, knowledge of the distribution and community structure of species in mid‐range trophic levels (e.g. macroinvertebrates) is lacking in most marine ecosystems. Our study aimed to examine the spatial distribution and community‐level biogeographic patterns of common kelp forest–rocky reef macroinvertebrates in Southern California and to evaluate the effects of environmental gradients on these communities. Quantitative SCUBA surveys were used to estimate macroinvertebrate densities at 92 sites from 2008–2012. Non‐metric multidimensional scaling was used to evaluate spatial patterns of macroinvertebrate communities among Regions. We found that kelp forest–rocky reef macroinvertebrate communities are distinct among different island and mainland regions, and their community patterns exhibited a strong relationship with an environmental gradient (i.e. sea surface temperature) even after controlling for geographic distance between sites. High abundances of urchin species (Strongylocentrotus purpuratus and Strongylocentrotus franciscanus) were strong drivers of regional differences. Macroinvertebrate community patterns were driven by characteristic species that were typically more prevalent at warmer or colder sites. Our results provide the first quantitative analysis of macroinvertebrate community structure within the California kelp forest ecosystem. We also describe the distribution and abundance of 92 conspicuous kelp forest‐rocky reef macroinvertebrates among nine pre‐defined Regions. This study provides important preliminary information on these macroinvertebrate species that will be directly useful to inform management of invertebrate fisheries and spatial protection of marine resources. 相似文献
96.
Spatial and ecologic distribution of neglected microinvertebrate communities across endangered ecosystems: meiofauna in Bali (Indonesia) 下载免费PDF全文
Francesca Leasi Camille Gaynus Angka Mahardini Tiara N. Moore Jon L. Norenburg Paul H. Barber 《Marine Ecology》2016,37(5):970-987
Biodiversity estimations, particularly in vulnerable tropical regions, are essential to understanding ecosystem structure, function and conservation. While threats to marine and terrestrial ecosystems have fueled increased interest in biodiversity research, information on meiofauna, a key trophic and ecologic community of microscopic organisms that lives within sediments, is still lacking. Here we report the results of a faunistic investigation conducted in Bali, Indonesia. The results reveal that the biodiversity of marine meiofauna in Bali is very high. Meiofauna from coral reefs, sand flats and seagrass beds differed significantly in abundance and diversity. Nonetheless, overall community compositions show that meiofauna communities are affected by environmental variables. The high meiofaunal diversity observed in Bali, a low diversity region of the Coral Triangle, indicates the importance of further meiofaunal research across this region and across a broader diversity of habitats. The data presented provide an important baseline for future studies on biodiversity conservation in the face of environmental changes due to anthropogenic impacts and/or natural events. 相似文献
97.
Piotr Kuklinski 《Polar research》2009,28(2):222-237
The Arctic is one of the most rapidly warming regions on Earth. This area is therefore very suitable for conducting studies focused on the influence of climate change on the biota. Marine communities of coastal waters are particularly sensitive to the current environmental changes (e.g., ice-scour intensity); understanding how community structure changes in response to local perturbations is thus important for providing an insight into how future communities may respond to climate change. This review focuses on the fauna colonizing stones of the Greenland Sea. It summarizes the current state of knowledge about the ecology of organisms inhabiting these substrata across a range of depths, from the intertidal to deeper parts of the continental shelf. In the intertidal zone, no stable or developed assemblage on the rocks is visible. The intertidal zone seems to be fully controlled by physical forces. In contrast, below the intertidal zone a rich and abundant fauna starts to appear on these substrata. Both biotic (e.g., competitive interactions) and abiotic (e.g., ice scour, size of the rock) processes seem to shape stone assemblages in the subtidal zone, yet their influence varies with depth. For example, the abundance of encrusting organisms decreases with depth, as does the intensity of competitive interactions. However, species richness on rocks seems to be in general higher in the deeper parts of the shelf. Possible scenarios of climate change influence on the encrusting biota, gaps in our knowledge about the ecology of stone-dwelling faunal assemblages, as well as possible directions of future research, are discussed. 相似文献
98.
生物标志的环境含义及其应用 总被引:2,自引:0,他引:2
卫民 《沉积与特提斯地质》1999,19(1):32-58
生物标志,包括生物的壳体构造、生态特征、地球化学和群落组合等,在地球科学研究中具有十分重要的理论意义和实用价值。本文首先论述了影响生物生存的环境因素,包括地球因素和宇宙因素。并根据西南地区晚古生代地层中主要生物门类,特别是微体古生物的古生态,论证生物标志的环境含义。在此基础上,指出生物标志在地学研究中的应用,包括划分和对比地层、判断沉积相、分析古气候变化、划分生物地理区、推断海(湖)平面变化、指示地质找矿和阐释宇宙演变。最后,探讨生物标志的研究方法,包括分类统计学方法、形态构造学方法、地球化学方法和沉积埋藏学方法。 相似文献
99.
珠江口以东近海水域污损生物的组成与分布 总被引:4,自引:0,他引:4
于1986年5月至1987年6月期间,在珠江口以东近海水域,距岸分别为15.7和71.7km、水深27和71km两处布设Z1和Z2两个浮标调查站,以研究该海区污损生物的组成及分布状况。结果表明,在相对近岸的Z1站,各水层的污损生物均以无柄蔓足类、海葵和双壳类及多毛类等华南沿岸海区常见种类为主,其中网纹藤壶占绝对优势;而远岸的Z2站,则主要是有柄蔓足类和水螅,且生物的种类和数量也远远低于Z1站。 相似文献
100.
分子标记技术及其在育种中的应用 总被引:1,自引:0,他引:1
Pan Jie 《中国海洋大学学报(自然科学版)》2000,30(Z1):25-31
九十年代后发展起来的分子标记技术因其所具有的 高效性和可靠性而得到广泛应用,也为动植物育种工作提供了新的研究手段。它可用于标记 辅助选择、品种鉴定、亲本选择等。分子标记辅助育种可以加速育种工作的发展,缩短育种 进程。目前,分子标记辅助育种在农作物如水稻、小麦、玉米,猪、牛、羊、鸡等家畜家禽 育种中已得到比较广泛的应用,积累了大量经验。综述近年来国内外分子标记辅助育种的研 究进展,并对海洋动物分子标记辅助育种工作的开展进行了初步探讨。 相似文献