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1.
UTILIZATIONANDSUSTAINABLEDEVELOPMENTOFISLANDMOUNTAINSINCHINA①ZhangYaoguang(张耀光)YangYinkai(杨荫凯)InstituteofMarineResources,Liao...  相似文献   

2.
The island mountain utilization is a kind of mountain utilization. Although the islands cover little area, they can be used as the base of marine development. The sustainable development of island mountains is of significance to marine development. There are more than 6500 islands (including the South China Sea Islets) in China, and most of them are continental islands which are the extension of continental mountains extent towards sea. For this reason, there are many hills but few mountains, the area of hills makes up more than two thirds of the whole land area. In order to keep ecological balance of islands, the utilization of island hills and mountains should take exploitation of forests as the main to conserve water source and water-soil, and forests become an important factor in keeping ecological balance and sustainable development of islands. At the same time we should make good use of forests through setting up forest nature protecting area and forest parks and developing forest tourism. A part of research achievements of the project subsidized by National Natural Science Foundation (No. 49171026).  相似文献   

3.
吴柯  杨帆  徐莹 《地质科技通报》2022,41(5):181-189
近年来, 受人类活动和全球变暖的双重影响, 我国南海区域珊瑚礁生态系统退化, 发生白化现象。利用遥感技术监测和掌握珊瑚礁的白化情况, 对南海生态环境的保护和治理具有重大价值。首先通过多期海表温度数据获取珊瑚礁白化预警的区域, 选定西沙群岛永乐环礁中的羚羊礁作为研究对象; 然后, 提出了一种新型的珊瑚礁白化监测模型, 分别采取水深校正、珊瑚礁分类、反射率调整以及阈值选择等方式对2013-2018年的Landsat-8遥感影像开展了多时间序列的珊瑚礁白化监测研究。最终的结果显示, 该模型能够较为准确地获取珊瑚礁白化区域, 为南海珊瑚礁白化现象的长时间序列监测提供依据。   相似文献   

4.
面向对象的南海珊瑚礁地貌单元提取   总被引:3,自引:0,他引:3  
南海珊瑚礁地貌信息的提取是珊瑚礁资源利用、生态保护与管理及可持续发展的重要地学基础。本文提出了面向对象的珊瑚礁地貌单元提取模型,针对不同的地貌单元,以不同地貌单元的最优分割尺度、光谱参数、形状参数来分割影像并合并成不同对象,从而获得相应的地貌单元。通过大量实验得出自然地貌的最优分割尺度区间为[140,600],其中附礁生物稀疏带及丛生带、礁坑发育带的光谱参数和形状参数分别为0.9和0.1,其他自然地貌单元的光谱参数和形状参数分别为0.8和0.2;人工地貌的最优分割尺度区间为[25,170],其光谱参数和形状参数分别为0.8和0.2。进一步以南沙群岛簸箕礁WorldView-2高分辨率遥感影像为例提取地貌单元,并结合混淆矩阵和Kappa系数对分类结果进行了精度评价,地貌单元提取总体精度达到了85.75%,Kappa系数为0.8349。结果表明,该方法可有效运用南海珊瑚礁遥感影像的光谱特征、纹理特征,以及影像数据不同波段的组合特性,综合了影像和珊瑚礁地貌的关联特性,充分利用了珊瑚礁不同地貌相带的异质性,获得了理想的南海珊瑚礁地貌的整体信息,满足了我国南海珊瑚礁地貌信息提取和地貌数字产品生成的需求。  相似文献   

5.
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?ο?1935?桢1951???2009?桶??????????2005?桶?????????????????????淽????????й?????????????????????????????????±???????????9??????????36???????????????????????????????Ч????  相似文献   

6.
分析了测高卫星同时应用于重力模型和地形模型时对计算南海地区岩石圈有效弹性厚度的影响,该影响可能会高估有效弹性厚度值。对比多项研究认为,南沙群岛地区岩石圈的有效弹性厚度约为9 km。通过对南海地区岩石圈的有效弹性厚度分布进行计算发现,南海海盆的有效弹性厚度最小约为4 km,南海周边的有效弹性厚度值较高,与海底岩石圈年龄的空间分布有较强的相关性,符合南海海盆扩张的历史。  相似文献   

7.
地名词典查询是地名校正、地名匹配等地名服务应用的重要基础,但是地名数量的快速增长使得词典查询性能面临严峻挑战。针对大规模数据环境中传统词典查询方法准确率不高且效率较低等问题,提出了一种顾及字符特征的中文地名词典查询方法(CGQM)。首先,查询具有相同字符特征的地名形成候选地名集合,同时构建单字索引提升查询效率;其次,依据字符数量特征比较查询地名与候选地名的差异,进一步过滤候选地名集合;最后,基于字符位置特征优化查询结果排序策略,使得结果排序更为合理。实验以全国地名词典为例,构建5组测试集进行CGQM方法与Lucene检索方法的对比分析。研究结果表明,CGQM方法对于增强地名词典查询功能、提升查询效率具有实际意义。  相似文献   

8.
采用实证分析法,分析了对马来西亚南海战略利益及政策,认为马来西亚南海政策具有较为明显的务实性、矛盾性、两面性特点,未来具有解决南海问题多边化、国际化的趋向,我国对此发展趋向应予以高度重视。  相似文献   

9.
Various geological processes and features that might inflict hazards identified in the South China Sea by using new technologies and methods.These features include submarine landslides,pockmark fields,shallow free gas,gas hydrates,mud diapirs and earthquake tsunami,which are widely distributed in the continental slope and reefal islands of the South China Sea.Although the study and assessment of geohazards in the South China Sea came into operation only recently,advances in various aspects are evolving at full speed to comply with National Marine Strategy and‘the Belt and Road’Policy.The characteristics of geohazards in deep-water seafloor of the South China Sea are summarized based on new scientific advances.This progress is aimed to aid ongoing deep-water drilling activities and decrease geological risks in ocean development.  相似文献   

10.
ESR dating of aragonitic and calcitic corals , eolianite , calcrete , and corallineae from coral reefs in the South China Sea was applied to study of Quaternary reef geology . The ESR ages of calcitic corals correlated with the biostratigraphy , lithostratigraphy and geochemistry of Well Xi-Chen-1 and the oxygen-isotope stratigraphy of deep sea sediments, were reliable and up to 1.26 Ma. The selection of signals for dating and other related problems are discussed .  相似文献   

11.
由于人类对现实世界进行认知和概念化的过程存在模糊性,许多人们在日常生活中使用的地名往往是没有明确边界范围的模糊区域。大数据时代的开启,为模糊地名空间范围的确定与表达提供了新思路。本文提出由k最邻近(k NN)离群点检测算法结合高斯混合模型(GMM)的方法,基于多源兴趣点(POI)数据获取模糊地名空间范围边界。该方法具有能有效识别离群点数据、参数敏感度低的特点。最后,分析了多源POI数据的应用对结果的影响。  相似文献   

12.
介绍了南海周边国家根据1982年《联合国海洋法公约》精神颁布的海洋法律,并叙述了这些国家的管辖区域主张以及与海洋划界有关的领海基线和基点等方面的问题。指出:南海周边国家之间若要划出专属经济区和大陆架边界线,包括我国在内的所有周边国家政府都应当修正不适宜的划界主张,并在划界原则、理论和方法上趋向一致,为早日划好边界,促进南海地区的经济发展和和平稳定而努力。  相似文献   

13.
In recent years, infrastructure construction on coral reefs has been increasingly developed. Therefore, the shallow strata stability of coral reefs in the South China Sea should be evaluated. This study aims to investigate the profiles for the shallow strata of coral reefs in the southwest of the Yongshu Reef, particularly in the hydrodynamic marine environment, and to establish a geological model for numerical simulation using Geo-Studio. The shallow strata of the coral reefs include mass gravel, sand gravel, mid-coarse sand, silty sand, fine sand, and reef limestone. The shallow reef slope near the lagoon is similar to a ‘layer cake', in which the side close to the sea is analogous to a ‘block cake'. The simulation results showed that coral reef stability depends on wave loads and earthquake strength and on the physical properties of coral reefs. The factor of safety for the outer reef is greater than 10.0 under static, wave, and seismic conditions; this indicated that the outer reefs were less affected by waves and earthquakes. However, the factor of safety next to the lagoon varied from 0.1 to 5.3. The variation was primarily caused by the thick strata of coral reefs close to the sea(reef limestone, typically with the thickness 10 m and equivalent to a block). The soil and rock layers in the coral reef strata with thicknesses 10 m showed weak engineering geological characteristics. Our findings can provide useful information to future construction projects on coral reefs.  相似文献   

14.
Coral bleaching has generally been recognized as the main reason for tropical coral reef degradation, but there are few long-term records of coral bleaching events. In this study, trace metals including chromium(Cr), copper(Cu), molybdenum(Mo), manganese(Mn), lead(Pb), tin(Sn), titanium(Ti), vanadium(V), and yttrium(Y), were analyzed in two Porites corals collected from Meiji Reef in the tropical South China Sea(SCS) to assess differences in trace metal concentrations in bleached compared with unbleached coral growth bands. Ti, V, Cr, and Mo generally showed irregular fluctuations in both corals. Bleached layers contained high concentrations of Mn, Cu, Sn, and Pb. Unbleached layers showed moderately high concentrations of Mn and Cu only. The different distribution of trace metals in Porites may be attributable to different selectivity on the basis of vital utility or toxicity. Ti, V, Cr, and Mo are discriminated against by both coral polyps and zooxanthellae, but Mn, Cu, Sn, and Pb are accumulated by zooxanthellae and only Mn and Cu are accumulated by polyps as essential elements. The marked increase in Cu, Mn, Pb, and Sn are associated with bleaching processes, including mucus secretion, tissue retraction, and zooxanthellae expulsion and occlusion. Variation in these trace elements within the coral skeleton can be used as potential tracers of short-lived bleaching events.  相似文献   

15.
中国南海珊瑚岛礁拥有巨大的资源潜力和科研价值。珊瑚岛礁第四系覆盖层结构为珊瑚砂和珊瑚骨架的松散堆积物,无胶结,钻探取心、成井极端困难。通过南海诸岛礁数百口钻井的施工实践,总结出"套管连续跟进干钻取心技术",工艺要点为4个步骤循环操作,称为"四步法"。使用该技术:①能确保珊瑚岛礁第四系覆盖层岩心采取率达到95%以上,并基本保持岩心原状性;②能实现在珊瑚岛礁第四系覆盖层中不使用泥浆护壁情况下安全钻进成井,达到避免地层过水通道堵塞、满足抽水试验要求的效果。研究成果对于珊瑚岛礁钻探具有重要的借鉴作用。   相似文献   

16.
17.
中国地图上应标注的藏南重要地名——巴昔卡   总被引:1,自引:0,他引:1  
对藏南地名——巴昔卡进行了研究与考证。介绍了巴昔卡作为中国雨都和雅鲁藏布大峡谷末端的基本情况,并根据汉藏语系中的珞巴语的特点,将巴昔卡的珞巴语含义推测为雅鲁藏布江边;强调了在《中国地图》上标注藏南地名点巴昔卡的重要性。  相似文献   

18.
南海区域渔船活动时空特征分析   总被引:1,自引:0,他引:1  
近年来海洋资源的不断开发利用,使得海洋空间规划变得尤为重要,其中以渔业资源占主要比重。为了对渔业资源监测与规划提供辅助决策信息,本文通过对南海及周边国家2018年船舶自动识别系统(AIS)数据进行预处理,采用数理统计和GIS空间分析方法,实现了南海区域渔船活动强度时空特征分析。结果显示: ① 2018年南海及周边国家渔船以区域性分布为主,集中在中国和越南沿海岸100 km以内区域,在秋季11月捕捞活动频繁,全年渔船平均活动强度白天大于夜晚,16:00 PM 时达到最大渔船活动强度; ② 中国在广东省、广西省和海南省各主要港口渔船活动强度呈现聚集性点状分布,渔船活动强度多大于100,部分港口附近海域呈条带状分布,西沙群岛相较南海其他群岛渔船活动强度较大,除越南外其他周边国家靠近南海附近海域部分海湾和港口有聚集式分布,渔船活动强度都小于2; ③ 越南渔船区域性分布明显,在胡志明港口呈现稳定的块状聚集性分布,且一年四季活动强度变化趋势不大,近岸渔船活动强度保持在50~100,越南渔船在中国南海禁渔线内靠近海南省西南部有两处活动较强的块状分布区域,2018年全年在此区域活动频率占采样天数的87.71%,且平均每小时有7~10艘渔船在该海域活动,休渔期内平均每小时渔船数量大于5,给中国南海海域渔业资源造成巨大威胁。本文通过AIS数据研究分析渔船活动可为海洋空间规划与政府相关部门提供数据支撑。  相似文献   

19.
Based on material deposited in the Marine Biological Museum of the Chinese Academy of Sciences(Qingdao),a new species,Lumbrineris sinensis sp.nov.,as well as Augeneria albidentata(Ehlers,1908),which is recorded for the first time from coastal water of China,are reported in the present paper.The specimens examined were collected during 1958 to 1960 from the Yellow Sea,East China Sea and South China Sea at depths of 4 to 182 m.  相似文献   

20.
Measurement of single-fish target strength in the South China Sea   总被引:4,自引:0,他引:4  
We measured the target strength (TS) of three commercial fish species: whitespotted spinefoot (Siganus canaliculatus), black porgy (Acanthopagrus schlegelii), and creek red bream (Lutjanus argentimaculatus), in the South China Sea. The TS of caged or tethered fish (n=76 total) was measured using a Simrad EY60 portable scientific echosounder at 120 kHz. We evaluated the relationship between TS and total length (TL, cm) for the three species. This is the first attempt to use split-beam acoustics to measure single-fish TS in the South China Sea by Chinese researchers. Our results will improve the accuracy and precision of acoustic abundance estimates of commercially important species and further the development of underwater acoustic survey techniques in fisheries in the South China Sea.  相似文献   

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