首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 31 毫秒
1.

In June 2004 China and Vietnam ratified both a maritime boundary agreement for the Tonkin Gulf (Beibu Gulf) and a fisheries cooperation agreement for the Gulf. These agreements end years of negotiation and debate regarding the rights of the respective states to the ocean areas and resources in the Gulf.  相似文献   

2.
 A small species (<90 mm SL) of the bagrid catfish, Pseudobagrus kyphus Mai, 1978, originally described from northern Vietnam, is newly recorded from China and redescribed in detail. The species is distributed in rivers flowing into Beibu Gulf (Gulf of Tonkin); i.e., the Song Hong River basin in northern Vietnam, and rivers on the southern side of Mts. Shiwan–Dashan in southernmost Guangxi Zhuangzu Autonomous Region, China. Partial nucleotide sequences of the mitochondrial DNA are also described and compared among the populations.  相似文献   

3.
Abstract

Vietnam claims a 12‐nautical‐mile territorial sea, a 12‐nautical‐mile contiguous zone, a continental shelf, a 200‐nautical‐mile exclusive economic zone (EEZ), historical waters encompassing most of the Gulf of Tonkin, and much of the Spratly Islands area. Vietnam's claimed boundaries overlap with those of China, Indonesia, Malaysia, Thailand, and Cambodia, and, in the Spratlys, with those of China, Taiwan, the Philippines, and Malaysia. The area claimed contains significant fisheries resources, and Vietnam has stipulated provisions for access to fish by foreign vessels. Yet issues pertaining to shared and migratory stocks remain to be addressed. Similarly, Vietnam has established regulations governing foreign ships navigating in Vietnamese‐claimed waters, including those designed to protect the environment. But some of these provisions do not conform to the provisions of the 1982 U.N. Convention on the Law of the Sea (UNCLOS). This article reviews Vietnam ‘s fisheries and navigation policies and issues.  相似文献   

4.
A full species composition of anemonefishes (Pomacentridae, Amphiprioninae) and their host sea anemones (Cnidaria, Actiniaria) from reefs of Phu Quy and Con Son Islands (off South Vietnam) and An Thoi Islands (northeastern Gulf of Thailand) is presented for the first time. A comparison of the faunas of anemonefishes and their host sea anemones is conducted in the coastal waters of Vietnam and adjacent waters. The presence of intermittent ranges of the anemonefishes in the coastal waters of Vietnam is demonstrated. For example, the ranges of two species, Amphiprion clarkii and A. frenatus, include the coastal waters of Vietnam, excluding the Gulf of Thailand, where they are not found even at the eastern border of the gulf. A. perideraion is absent in the Gulf of Tonkin, but it is distributed to the south along the entire coastal zone of Vietnam, including the Gulf of Thailand. In the coastal waters of Vietnam, A. sandaracinos is distributed only between the Gulf of Tonkin and Gulf of Thailand. A. polymnus is reliably indicated in the coastal waters of Vietnam between 12°50′ and 9°54′ N, but, most likely, its range is continuous along the entire Vietnamese coast. The richness of species composition of host sea anemones decreases (from nine to three species) in the southern direction, from Central Vietnam to the eastern border of the Gulf of Thailand.  相似文献   

5.
Geological events, landscape features, and climate fluctuations have shaped the distribution of genetic diversity and evolutionary history in freshwater fish, but little attention has been paid to that around the Gulf of Tonkin; therefore, we investigated the phylogeographic structure of the dwarf snakehead (Channa gachua) on Hainan Island and mainland China, as well as two populations in Vietnam. We attempted to elucidate the origins of freshwater fish in South Hainan by incorporating genetic data from DNA markers on both the mitochondrial cytochrome b gene (cyt b) and the nuclear recombination‐activating gene 1 (RAG‐1). Mitochondrial phylogenetic analysis identified two major lineages (lineages A and B), which may represent separate species. Divergence data suggested that C. gachua populations diverged between 0.516 and 2.376 myr. The divergence of the two cryptic species is congruent with sea‐level rise, which subsequently isolated Hainan from the mainland. During the Pleistocene glaciations, the entire region of the Gulf of Tonkin and the Qiongzhou Strait became part of the coastal plain of the Asian continent, which might have resulted in the current distribution patterns and dispersal routes of C. gachua populations. The formation of three sublineages in lineage A indicated that the Gulf of Tonkin was a geographical barrier between Hainan Island and mainland China but not between Vietnam and Hainan Island. The results of this study may help to elucidate the origins of freshwater fish in South Hainan and the phylogeographic structure of C. gachua.  相似文献   

6.
7.
Butterflyfishes (Chaetodontidae) from the reefs of Ly Son Archipelago (northern Central Vietnam) are reviewed. In total, 16 species of chaetodontids from three genera (Chaetodon, Forcipiger, and Heniochus) are found. All species are documented by underwater photos, and they have not been registered off Ly Son Islands before. A comparison of chaetodontid faunas off Ly Son, Cu Lao Cham, and Paracel islands; in the Gulf of Tonkin; and in southern Central Vietnam is conducted.  相似文献   

8.
The parasite fauna of Epinephelus coioides can be used as an indicator to assess different aquaculture systems. A total of 133 E. coioides were collected from fishermen (wild fish) and marine fish farms (net cages, pond farms) in the Gulf of Tonkin (Ha Long, Cat Ba and Nghia Hung), Vietnam in 2013 and 2014, and examined for the presence of protozoan and metazoan parasites. Different patterns of parasite infections were found. The monogenean Pseudorhabdosynochus spp. was predominant in the net cage system; and the protozoans Trichodina spp. and Cryptocaryon irritans were found exclusively in pond and net cage cultivation sites in Nghia Hung and Cat Ba. These three species were assessed in addition to seven further indicator species and two dominance indices, to visualize the potential of assessing different aquaculture systems in Vietnam. This suggests the use of former shrimp ponds for grouper cultivation, reducing the pressure to further extend net cage cultivation in already highly influenced mariculture regions in Vietnam.  相似文献   

9.
Yufa Luo  Shuqiang Li 《Ecography》2018,41(2):414-423
Stedocys spitting spiders (Araneae: Scytodidae) inhabit subterranean environments and have poor dispersal abilities. The Cenozoic Indian–Eurasian collision affected the regional biota of this genus, which occurs in parts of Indochina. Phylogeographical pattern of Stedocys based on multigene DNA sequence datasets reveals how tectonic history drove four biological splits. The first split dates to the late Paleocene–Eocene and involves the Truong Son Mountain Range and Mekong River. The other splits associate with the Eocene–Oligocene transition, including the Tonkin (Beibu) Gulf, the Ma River, and the Red River. These events indicate four early uplifts of the Himalayas and Tibetan Plateau. Our results cannot reject the hypothesis that uplifting of the Himalayas and Tibetan Plateau region due to crustal thickening and the lateral extrusion of Indochina occurred synchronously during the Paleocene–Oligocene transition in reaction to the Indian–Eurasian collision. Species of Stedocys cluster into groups I and II. Their evolution involves one dispersal and four vicariance events, which formed the following five Indochinese clades: Hainan clade (I‐1); western Yunnan and central Laos clade (I‐2); central Vietnam clade (I‐3); northern Vietnam and southwestern China clade (I‐4); and Thailand clade (II‐1). The lateral extrusion of Indochina is the driver of these events. The drifting of Hainan Island to its present location owes to its southeastern movement from continental Vietnam and Guangxi, China around the Eocene–Oligocene boundary. This biogeographical pattern highlights the significant role geography plays in shaping evolutionary history in southeastern Asia. It also illuminates how the timing of geological events drives the distributions of species.  相似文献   

10.
陈佳琪  李潮  张雯君  李炜  高天扬  赵俊 《生态学报》2019,39(7):2591-2602
为了解海南岛宽额鳢(Channa gachua)的群体遗传分化和亲缘生物地理过程,采集了云南元江和海南岛5个水系(昌化江、陵水河、藤桥河、万泉河及南渡江)共6个种群168个宽额鳢个体,基于线粒体细胞色素b(Cyt b)基因全序列(1142 bp)对其遗传多样性和遗传分化程度进行了评估,并探讨了地质和气候等因素如何塑造了这一物种的亲缘地理结构及演化历史。基于Cyt b序列构建的系统树结果将所有个体分成两个主要谱系(A和B),谱系A包括海南岛所有种群,其中,部分昌化江个体形成独立的亚支(A2),其余个体聚为另一亚支(A1),谱系B为云南元江的全部个体,各谱系间的遗传分化指数均较高。种群历史动态分析表明,各谱系均没有发生种群扩张,但A1亚支与谱系B曾在约1万年前发生过有效种群数量减小的事件。根据研究结果推测,更新世冰期期间,北部湾因海平面下降而暴露,大陆和海南岛的水系发生接触,越南北部水系(包括元江/红河)通过一条联系雷州半岛和海南岛的古河道流入南海,因而冰期期间宽额鳢有机会从元江(红河)扩散至海南岛西南部,随后在海南岛内部,宽额鳢进一步扩散,并以五指山为种群间基因交流的重要地理障碍,各水系间种群发生基因交流和遗传分化。  相似文献   

11.
The paper analyzes both published and unpublished results of the investigations of Vietnamese reef-building corals and reefs performed in the last decades of the twentieth century. The state of the art in the study of reef-building scleractinian corals and reefs is presented. The scleractinian fauna of Vietnam is shown to match in species diversity (366 species of 70 genera) the tropical coral fauna of the Indonesian-Malacca fertile center, from which Indo-Pacific reef-building corals originated. The whole Vietnam coast from the Gulf of Tonkin to the Gulf of Siam is a biogeographically single whole and is a part of the Indo-Polynesian Province of the Indo-Pacific Area.  相似文献   

12.
本文对北部湾中部海域水深2.4m到61m、共计184个站位表层沉积物中的有孔虫进行研究。结果显示浮游有孔虫丰度非常低,种类也较稀少,仅在南侧水深较大的少数站位有发现,且含量不超过5%;而底栖有孔虫则较丰富,多数样品中以含有螺旋式与平旋式的玻璃质壳类型为主,暖水或大型底栖有孔虫分子常见。和其它海区相较而言,该海域底栖有孔虫中胶结壳类含量偏高,可能与沉积物底质颗粒较粗及海水盐度较低有关。该研究详细报道了底栖有孔虫主要属种在北部湾的分布特征。与海洋环境对比显示,水深和沉积物底质类型是影响这些属种平面分布的主要因素,而湾外温暖水团则是控制暖水种分子分布的另一重要因素。  相似文献   

13.
A platform reef at Bach Long Vi Island (Gulf of Tonkin in the South China Sea) was investigated for the first time. In all, 264 species of corals and their accompanying species of macrobenthos were found. Among the scleractinian corals, acroporids, poritids, and mussids dominated. Monospecific aggregations of alcyonarians Sinularia and Lobophytum and the hydroid Millepora were rather numerous. Based on its geomorphological characteristics, coral species diversity and zonal distribution, the investigated reef is comparable with ribbon and platform reefs on the Great Barrier Reef in Australia and in the Indian Ocean.  相似文献   

14.
叉突杆蝉属一新种及一中国新记录种(同翅目:叶蝉科:杆叶蝉亚科)沈林,张雅林(陕西省杨陵区西北农业大学昆虫研究所,陕西省杨陵区712100)叉突杆蝉属Kalasha由Distant建立于1908年,该属现仅知2种,分布于印度(阿萨姆)和印度尼西亚(苏门...  相似文献   

15.
This paper deals with the history and results of the studies of reefs and coral communities of the Gulf of Tonkin based on published and unpublished materials, including the author's. The state of the art in the study of reef-building scleractinian corals and reefs of this region is reported. The peculiar nature of the reefs studied is caused by the monsoon climate in the region and river runoff waters cooled to 16–18°C, silted to 100 g/m2 per day, and freshened to 28‰ in the wintertime, i.e., conditions far from optimum for reef formation. The silting and eutrophication of the gulf waters resulted in a change in the composition and structure of the coral reef communities via the reduction or elimination of certain coral species. Instead of acroporids, typical for the majority of other reefs, reef communities of the Gulf of Tonkin are dominated by poritids and faviids, which form the framework of the reefs. These peculiarities make the reefs of the Gulf of Tonkin really unique.  相似文献   

16.
17.
The present study describes a new record of the rare portunid crab Carupella banlaensis from Goa, along the central west coast of India, based on carapace and appendage morphology and provides detailed morphometric measurements of two immature female specimens. Carupella banlaensis differs from its congeners in possessing less prominent median and lateral frontal lobes, the first eight anterolateral teeth alternating large and small and bluntly triangular, the cheliped merus with three large spines on the anterior margin and one distal spine on the posterior margin. Previously known only from the Gulf of Tonkin (China) and Somalia, the present observation of this crab is a new record for the entire South Asian region.  相似文献   

18.
Coral communities were investigated on 16 reefs in open and closed bays, in straits, and around capes of different islands of the Bai Thu Long Archipelago (Gulf of Tonkin, South China Sea). Variations observed in the communities of Acropora aspera + Goniopora columna, Goniopora stokesi + Galaxea fascicularis, Acropora aspera, Goniopora columna, and Pavona decussata + Pavona cactus are caused by different ecological conditions and may be linked with sedimentation flux within the water column and near the bottom, as well as with the rate of integral water exchange and resuspension above the coral settlements.  相似文献   

19.
The 1985 Guinea/Guinea‐Bissau maritime boundary case was a landmark decision in maritime delimitation. For the first time, sub‐Saharan African states resorted to third‐party settlement, thereby making a significant contribution to the developing state practice on maritime delimitation. The Arbitration Tribunal took an unprecedented “regional approach,”; which had a direct effect on the two neighboring countries, Senegal and Sierra Leone. The Award provides lessons for unresolved conflicts and has implications for areas of future dispute such as in the Gulf of Guinea, where Cameroon has initiated proceedings against Nigeria.  相似文献   

20.
Material on the genus Paraploactis from the fauna of Vietnam is revised. Two species, P. obbesi and P. hongkongiensis, are registered in the fauna of Vietnam; the latter species is described in Vietnam for the first time. The adult and juvenile exemplars from three nominal species of the P. kagoshimensis-complex are described in detail, and new characters valuable for identification of the species within the complex are revealed. The possibility of an occurrence of a species related to P. hongkongiensis in the Gulf of Siam is proposed. This species differs from P. hongkongiensis in the degrees of development of the interorbital crests, interorbital hollow, and teeth spot on the vomer, as well as patterns of the structure of the postcranial skeleton, and several other features. The genus Paraploactis is found in the Gulf of Siam for the first time.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号