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1.
Multispectral satellite remote sensing can predict shallow-water depth distribution inexpensively and exhaustively, but it requires many in situ measurements for calibration. To extend its feasibility, we improved a recently developed technique, for the first time, to obtain a generalized predictor of depth. We used six WorldView-2 images and obtained a predictor that yielded a 0.648 m root-mean-square error against a dataset with a 5.544 m standard deviation of depth. The predictor can be used with as few as two pixels with known depth per image, or with no depth data, if only relative depth is needed. 相似文献
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Izvestiya, Atmospheric and Oceanic Physics - The authors describe features and the operation of an integrated ground to space monitoring system for studying anthropogenic effects on coastal waters... 相似文献
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以黄河口典型滨海湿地为实验区,采用主客观评价相结合的方法,在与SPOT-6卫星影像对比的基础上进行了GF-2卫星全色影像、多光谱影像以及融合影像的质量评价。目视主观评价表明,GF-2影像在滨海湿地地区整体表现能力上与SPOT-6影像相近,地物边界、纹理等细节信息方面优于SPOT-6影像;基于统计指标的客观评价结果显示,GF-2影像受噪声干扰的程度小于SPOT-6影像,承载的信息量与SPOT-6影像接近,多光谱影像以及融合影像各波段间的独立性也与SPOT-6影像相当,但在灰度、离散程度和地物可分性上与SPOT-6影像还存在一定的差距。 相似文献
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Izvestiya, Atmospheric and Oceanic Physics - In this paper, the possibilities of recording the spectra of spatially inhomogeneous sea waves using high-spatial-resolution satellite imagery to... 相似文献
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This paper summarizes the results of perennial combined satellite monitoring of the Black Sea conducted in order to detect sea-surface oil and oil-product pollution, as well as biogenic and anthropogenic surfactant films. A joint analysis of data obtained by various remote sensing techniques has been performed. The large amount of data has resulted in generalizations and reliable statistics on the spatial and temporal variability of different film manifestations in radar images of the sea surface. Regions most severely polluted by petroleum products have been identified. A hypothesis is suggested linking the surface manifestations of certain types of polluting films with natural gas and oil seeps and mud volcanism in the Black Sea. Improvements in the reliability of interpreting satellite data are discussed. 相似文献
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Oceanology - The quantitative development of Mnemiopsis leidyi, the species structure of mesoplankton, and the food spectrum of ctenophores were studied in the shelf zone off the Crimean coast of... 相似文献
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潮间带水沙多层位同步测量系统应用的初步研究 总被引:2,自引:0,他引:2
利用水压、光电转换原理研制成的多层位水沙同步测量系统(WCT系统)不仅可测量潮间带水位随时间的变化系列、同一层位的浊度及流速,还可以同步观测这些参数在潮间带水流剖面不同层位上的变化。野外对比试验表明,WCT系统获得的流速值与直读式流速仪的测量结果基本一致,平均相对误差为14.52%;悬沙传感器经野外现场率定获得悬沙浓度,平均相对误差为21.96%,精度比室内率定提高—倍以上。悬沙粒径是影响悬沙浓度测量精度的主要因素。此外,自然环境(如海水温盐度)的变化及仪器本身的特性也可能影响到测量结果。因此,WCT系统在潮间带的水位、流速和悬沙浓度的观测和边界层研究方面有相当潜力。 相似文献
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By treating observations involving long-term buoy moorings, numerical characteristics of the periods, amplitudes, phases and
orbits of inertial currents in some Black Sea areas have been obtained. The inertial component's contribution to the total
velocity field and turbulent exchange has been determined. As a result, the maximal heights of the internal waves generated
by the inertial currents have been estimated.
Translated by Vladimir A. Puchkin. 相似文献
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因气候变暖导致的海平面上升是全球面临的海洋问题。为加强海南岛的海洋防灾减灾工作,保障其沿海地区的生态环境和经济社会发展,文章在调查评估的基础上,分析海平面上升对海南岛沿海地区的影响,并提出对策建议。研究结果表明:我国沿海海平面总体呈波动上升趋势,海南岛沿海海平面的上升速率居全国之首;海平面上升对海南岛沿海地区的影响主要包括淹没滨海低地和减小旅游区沙滩面积,加重风暴潮、海岸侵蚀、海水入侵和土壤盐渍化、洪涝的灾害程度以及影响海岸防护设施等方面;在海南岛沿海地区发展中,应充分考虑海平面上升的因素,加强灾害风险抵御能力建设、城市科学规划、海平面观测和监测以及受损岸线整治修复等工作。 相似文献
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Based on historical wind fields in the Bohai Sea,a sequence of annual extremal wave heightsis produced with numerical wave models for deep-water and shallow water.The design wave heights withdifferent return periods for the nearest deep-water point and for the shallow water point are estimated onthe basis of P-Ⅲ type,Weibull distribution,and Gumbel distribution;and the corresponding values for theshallow water point are also estimated based on the HISWA model with the input of design wave heightsfor the nearest deep-water point.Comparisons between design wave heights for the shallow water point es-timated on the basis of both distribution functions are HISWA model show that the results from differentdistribution functions scatter considerably,and influenced strongly by return periods;however,the resultsfrom the HISWA model are convergent,that is,the influence of the design wave heights estimated with dif-ferent distribution functions for deep water is weakened,and the estimated values decrease for long 相似文献
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Regular surveys of coastal zone seabed deliver important information about geomorphologic processes such as silting of waterways. The recent introduction of the Sentinel series of sensors has allowed for the use of satellite sensing for shallow bathymetry morphology monitoring. In this context, this article presents a dedicated Geographic Information System for Baltic Sea shallow water depth monitoring on the basis of Sentinel-2 imagery. The system employs Geovisual Analytics for differential analysis of bathymetry changes as well as monitoring the visibility of known wrecks in the coastal waters of Southern Baltic Sea. Results are verified with regard to known changes in shallow water bathymetry between 28 June 2015 and 3 March 2017. 相似文献
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D. Tolmazin 《Progress in Oceanography》1985,15(4):217-276
This article describes the hydrography of the Northwestern Shelf (NWS), of the Black Sea emphasizing the changes induced by water management in the Dniejer and Dniester river basins. The existing literature and previously unpublished data have been reviewed and synthesized to describe water property fields and transport mechanisms of the NWS and the Dnieper and Dniester estuaries before the early 1960s, or the so-called precontrol period, when the effect of artificial river flow control upon the coastal waters was insignificant.After the hydroenergy complexes and water withdrawal and disposal systems on rivers became fully operational in the early 1970s (the so-called postcontrol period), the annual river discharge from the Dnieper and Dniester had noticeably decreased and seasonal river flow patterns had been artificially modified. Instead of a powerful and short early spring flood, typical for the natural conditions in the Dnieper river, the hydrographs in the postcontrol period exhibit two smaller peaks of river discharge of much longer period. One of them (winter-early spring) is caused by intense hydroenergy generation and weir discharges through the cascade of storage reservoirs. Another is associated with spring flood, modified by intense water consumption and storage in this period. High average river discharge in late May—early June strengthened the summer pycnocline which inhibits vertical mixing in the estuaries and coastal waters. Owing to a slow summer circulation, the rate of natural purification of the entire coastal system has been reduced. This coupled with the increased nutrient, organic and pollutant transport, decreased the dissolved-oxygen concentration and led to anoxic events and mass mortalities of marine organisms in the previously productive regions. These effects have primarily plagued the benthic communities along the entire western coast of the NWS since 1973.Winter convective overturn in the Black Sea reaches its maximum depth at the southern boundary of the NWS. Thus, the NWS waters descend beneath the seasonal and main thermoclines in the open sea and are spread by the prevailing currents across the entire sea in the cold intermediate layer (CIL). By this dynamic mechanism the projected man-made modifications in the riverine-estuarine systems of the NWS will affect and change the large-scale thermohaline structure and marine life of the Black Sea. 相似文献
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Artamonov Yu. V. Skripaleva E. A. Kolmak R. V. Fedirko A. V. 《Izvestiya Atmospheric and Oceanic Physics》2020,56(9):1007-1021
Izvestiya, Atmospheric and Oceanic Physics - The structure and seasonal variability of temperature frontal zones and fronts in the Black Sea are studied on the basis of a modern high-resolution... 相似文献
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为海洋监测设备实验水槽的设计和模型实验的开展提供动力环境方面的依据,分析了中国近海和各大洋典型海域浪、流、风等环境要素的特征,对中国近海给出环境要素特征量的平均值和最大观测值,对大洋给出统计的最大概率对应的要素值和1%概率大值;模拟能力评估显示,实验水槽对浪、流、风均具有很好的模拟能力,可满足今后对海洋监测设备开展的各类模型实验需要。 相似文献
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Guo Congcong Bai Xiaoyun Abdullah Al Mamun Sikder Mohammad Nurul Azim Xu Henglong 《Ocean Science Journal》2019,54(1):87-95
Ocean Science Journal - Biological trait analysis (BTA) of protozoan communities has been used a useful bioindicator of environmental quality status in marine ecosystems. To determine the optimal... 相似文献
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针对渤海及附近海区的曲折岸线变化以及水文资料时空分布不均匀性的特点,使用四维客观分析LOESS方法得到逐月气候态盐度场。结果表明:渤海南部沿岸水扩展和运移受季风影响显著。冬季沿岸水向渤海湾和莱州湾堆积,形成沿山东半岛龙口海岸东向爬行的水舌,该水舌在蓬莱水域向东扩展;夏季沿岸水向渤海中部冲溢,特别是在黄河口附近,其核心区厚度可达8 m,可扩展到119°30′E处,同时莱州湾内的沿岸水向湾内西部收缩。冬季渤海海峡呈现显著北进南出水交换态势;夏季渤海海峡定常流方式的水交换特征不明显。 相似文献
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规范养殖用海的几点思考 总被引:1,自引:0,他引:1
养殖用海属渔业用海范畴,是我国用海面积最大的用海类型.我国沿海有适宜发展海水养殖的浅海滩涂483万公顷,现有养殖用海面积145万公顷.由于养殖用海面广量大,养殖主体错综复杂,用海观念陈旧落后,尽管《中华人民共和国海域使用管理法》已颁布实施多年,但截至目前仍有30%以上的养殖用海项目未纳入海域使用管理的范畴.鉴于此,笔者就开展养殖用海专项执法工作,进一步规范养殖用海活动,结合工作实践谈几点粗浅的认识. 相似文献