海洋生态重要性区域的内涵与识别方法研究——以黄河口为例   总被引：3，自引：0，他引：3  

SHEN Zhiliang  YAO Yun  WU Yulin 《海洋学报(英文版)》2016,35(10):20-27

海洋生态环境目前正在承受来自人类活动和气候变化的巨大压力;急需必要的管理工具或决策支持系统来应对这些压力所带来的生态环境问题。对海洋生境的分类识别是开展生物多样性保护的基础和前提;海洋生态重要区识别作为一种客观、科学和灵活的生境分类评估和选划方法;已被科学界和管理者广泛接受和认可。本文首先介绍了海洋生态重要区的概念内涵以及识别方法的研究进展;给出了海洋生态重要区的定义;之后以黄河口为例;初步建立了针对该区域的生态重要区识别标准和评价方法;对黄河口及邻近海区进行了生态重要性等级划分。本文是对生态重要区识别方法在我国近海的首次应用尝试;研究结果可为我国基于生态系统的海洋管理提供科学方法和工具;也可为其他区域的研究提供借鉴。  相似文献   

Radar-based collision avoidance for unmanned surface vehicles     

庄佳园  张磊  赵士奇  曹建  王博  孙寒冰 《中国海洋工程》2016,30(6):867-883

Unmanned surface vehicles (USVs) have become a focus of research because of their extensive applications. To ensure safety and reliability and to perform complex tasks autonomously, USVs are required to possess accurate perception of the environment and effective collision avoidance capabilities. To achieve these, investigation into realtime marine radar target detection and autonomous collision avoidance technologies is required, aiming at solving the problems of noise jamming, uneven brightness, target loss, and blind areas in marine radar images. These technologies should also satisfy the requirements of real-time and reliability related to high navigation speeds of USVs. Therefore, this study developed an embedded collision avoidance system based on the marine radar, investigated a highly real-time target detection method which contains adaptive smoothing algorithm and robust segmentation algorithm, developed a stable and reliable dynamic local environment model to ensure the safety of USV navigation, and constructed a collision avoidance algorithm based on velocity obstacle (V-obstacle) which adjusts the USV’s heading and speed in real-time. Sea trials results in multi-obstacle avoidance firstly demonstrate the effectiveness and efficiency of the proposed avoidance system, and then verify its great adaptability and relative stability when a USV sailing in a real and complex marine environment. The obtained results will improve the intelligent level of USV and guarantee the safety of USV independent sailing.  相似文献   

Paratacamite from Gypsum Veins in Sandstones of the Kuqa Basin,Xinjiang, China: Implications for a New Epigenetic Cu Enrichment Mechanism          下载免费PDF全文

Yangtong Cao  Chenglin Liu  Pengcheng Jiao  Chunlian Wang 《Resource Geology》2016,66(2):114-126

The Kuqa Basin filled with Paleogene evaporite series is located in the northeast of the Tarim Basin, Xinjiang, China. It is famous for sandstone‐hosted Cu deposits formed by synsedimentary processes. However, our recent studies reveal that there has been another Cu mineralization mechanism in this basin. Field investigations show that there is a close relationship among faults, salt domes, and brine. Cu deposits are mainly located in two east–west‐trending anticlinal belts in the basin, adjacent to salt domes in the belts. Cu minerals in gypsum veins of the Jidike and Kangcun formations have been investigated by SEM, EDS, and X‐ray diffraction methods. The occurrence of paratacamite in gypsum veins has been reported to coexist with glauberite and halite in the joint planes of sandstones. In addition, it occurs accompanying residual crystal salt encrustation in limestone fractures, or in sandstones in dendritic form. These features indicate that the surface‐Cu enrichment in the Kuqa Basin might have originated from Cu‐bearing brine in the underlying evaporite units, which migrated upward along fractures. In addition, the presence of H₂S in the east–west fault belt in the Kuqa Basin, and the discovery of surface sulfur, calcium carbonate, and covellite, suggest thermochemical sulfate reduction near salt domes in the deeper parts of the rock units. This process resulted in the generation of reduced brine and provided a favorable environment for Cu enrichment. Therefore, the surface‐Cu mineralization near salt domes is interpreted to be the result of Cu‐bearing brine migrating upward to the surface along faults (or joints) following the intrusion of deep salt domes. The geological evidence indicates the presence of reducing brine and Cu‐bearing brine near the salt dome in the deeper rocks of the Kuqa Basin, thus making the intrusive contact zone of the salt dome a favorable site for the epigenetic enrichment of Cu. Our study demonstrates that Cu enrichment in the Kuqa Basin resulted not only from synsedimentary deposition but also through epigenetic enrichment associated with salt dome intrusion and brine‐rich fluids.  相似文献   

Non-capacity transport of non-uniform bed load sediment in alluvial rivers     

Zhi-xian Cao  Peng Hu  Gareth Pender  Huai-han Liu 《山地科学学报》2016,13(3):377-396

Rivers often witness non-uniform bed load sediment transport. For a long time, non-uniform bed load transport has been assumed to be at capacity regime determined exclusively by local flow. Yet whether the capacity assumption for non-uniform bed load transport is justified remains poorly understood. Here, the relative time scale of non-uniform bed load transport is evaluated and non-capacity and capacity models are compared for both aggradation and degradation cases with observed data. As characterized by its relative time scale, the adaptation of non-uniform bed load to capacity regime should be fulfilled quickly. However, changes in the flow and sediment inputs from upstream or tributaries hinder the adaptation. Also, the adaptation to capacity regime is size dependent, the finer the sediment size the slower the adaptation is, and vice versa. It is shown that the capacity model may entail considerable errors compared to the non-capacity model. For modelling of non-uniform bed load, noncapacity modelling is recommended, in which the temporal and spatial scales required for adaptation are explicitly appreciated.  相似文献   

Determination of internal controls for quantitative gene expression of Isochrysis zhangjiangensis at nitrogen stress condition     

Shuang Wu  Jiannan Zhou  Xupeng Cao  Song Xue 《中国海洋大学学报(英文版)》2016,15(1):137-144

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Identification of light-harvesting chlorophyll a/b-binding protein genes of Zostera marina L. and their expression under different environmental conditions     

Fanna Kong  Yang Zhou  Peipei Sun  Min Cao  Hong Li  Yunxiang Mao 《中国海洋大学学报(英文版)》2016,15(1):152-162

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Determining sources of mine water based on hydraulic characteristics analysis of a fault system     

Mei Yao  Peigui Liu  Manting Shang  Yuezan Tao  Chao Lei  Lugan Cao 《Environmental Earth Sciences》2016,75(10):858

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Aqueous geochemistry and its influence on the partitioning of arsenic between aquifer sediments and groundwater: a case study in the northwest of the Hetao Basin   总被引：1，自引：0，他引：1  

Ping Ni  Huaming Guo  Yongsheng Cao  Yongfeng Jia  Yuxiao Jiang  Di Zhang 《Environmental Earth Sciences》2016,75(4):356

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Statistical meso-damage model for quasi-brittle rocks to account for damage tolerance principle     

Heng Zhao  Chao Zhang  Wen-gui Cao  Ming-hua Zhao 《Environmental Earth Sciences》2016,75(10):862

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Analysis of phosphorus import characteristics of the upstream input rivers of Three Gorges Reservoir     

Chaonan Han  Binghui Zheng  Yanwen Qin  Yingqun Ma  Wei Cao  Chenchen Yang  Zhichao Liu 《Environmental Earth Sciences》2016,75(12):1024

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