南黄海、东海鲐鲹鱼索饵场浮游动物生态特征

本文采用比较的方法,研究了黄海南部东海北部和东海中南部两个鲐鲹鱼索饵场浮游动物生态特征。结果表明,南部渔场生物量的极差、变异系数小于北部渔场。若扣除个别站位的影响,则南部渔场的平均值高于北部渔场。北部渔场群落多样度、均匀度、丰富度、单纯度较高,南部渔场则相反。北部渔场浮游动物优势种较少,且大多数种具有较高的聚集强度;而南部渔场优势种较多,优势度低,聚集性差。     

陕西米仓山地区爬行动物初报

米仓山位于陕西西南部,是陕甘川三省交会的主要山脉(东经105°30′—108°30′,北纬32°00′—33°00′)。米仓山地区的爬行动物尚未见有报道。笔者从1982年5月14日—10月12日,在米仓山地区的宁强、镇巴等县,选点调     

依据大规模捕捞统计资料分析东黄渤海白姑鱼种群划分和洄游路线

根据我国10多个主要渔业公司1971-1982年间白姑鱼(Argyrosomus argentatus)捕捞统计资料,从产量分布,鱼群移动等方面,研究了东黄渤海白姑鱼的种群划分和洄游路线。结果显示,我国沿海白姑鱼可分为2个种群。其中,黄渤海种群越冬场主要在黄海中部34°00'N以北水域。每年3-4月份,鱼群陆续进入山东半岛的乳山沿海、渤海各海湾、黄海北部沿岸和海州湾产卵。栖息在渤海的白姑鱼9-11月份在渤海中部索饵,形成越冬群体,11月后绕过成山头向越冬场洄游,12月至1月份到达越冬场;东黄海种群越冬场主要是在东海外海和中南部近海。每年3-4月份东海外海白姑鱼向西进入舟山渔场。在舟山渔场,这部分鱼群与从东海中南部近海北上的产卵群体汇合,向西进入舟山群岛沿海水域产卵。到了5月份,在浙江北部近海形成索饵群体。6-8月份,索饵群体经过长江口北上黄海南部近海索饵,9月份,索饵群体前锋到达34°00'N禁渔线外侧。此后,索饵场的白姑鱼向南做越冬洄游,并在10月份回到长江口。从这里,一部分群体游向外海越冬场,一部分群体继续南下回到东海中南部近海的越冬场。另外,在东海中南部近海越冬群体,部分就近游向沿岸的海湾,河口产卵,产卵后在产卵场外侧索饵,冬季回到就近的越冬场。     

东、黄海水团动态与夏季休渔效果间的关系

用聚类分析法分析了2003年6月-2005年6月东、黄海水团的分布,并讨论了水团动态变化与夏季休渔效果间的关系。结果表明,6月表层水团主要包括东海表层水团、黄海水团、黄-东海混合水团和沿岸冲淡水,底层水团主要包括东海次表层水团、黄海冷水团和黄海水团。另外,各水团的分布面积存在年间差异。夏季休渔期间,中上层鱼类资源和底层鱼类资源的恢复速度均在2005年最快,在2003年最慢。9月东、黄海中上层鱼类的主要作业渔场在28°00′-32°30′N,125°30′E以西海域,该海域表层主要受东海表层水团所控制;底层鱼类的主要作业渔场在29°30′-33°00′N,127°00′E以西海域,该海域底层主要受东海次表层水团所控制。6月较强的东海表层水团有利于中上层鱼类资源的恢复;较强的东海次表层水团有利于底层鱼类资源的恢复,而较强的黄海冷水团不利于底层鱼类资源的恢复。     

东海区沙海蜇和浮游动物的分布特征

根据2003—2005年夏、秋季在东、黄海进行的大型水母监测调查资料,分析了沙海蜇及其分布区内浮游动物的数量动态分布特点,研究了浮游动物优势种的生态类型及其种间变化。结果表明:夏季沙海蜇主要分布于29°00′—34°00′N海域,秋季主要分布于31°00′—34°00′N海域;3年间,沙海蜇生物量逐年递减、分布范围逐年变小,但并不影响东海、黄海沙海蜇从夏季至秋季具有由东海北部向黄海逐渐移动的特点;沙海蜇分布海域浮游动物的高生物量密集区一般位于沙海蜇中心区的边缘区域;沙海蜇和浮游动物的生物量在空间分布上存在着明显的负相关关系;浮游动物优势种夏季为中华哲水蚤与长尾类溞状幼体,秋季为中华哲水蚤、肥胖箭虫和小齿海樽。浮游动物与沙海蜇的生物量变化有较好的对应关系,浮游动物生物量大小与主要优势种组成可作为分析年间沙海蛰是否暴发的重要参考。     

黄海南部和东海小黄鱼(Larimichthys polyactis)产卵场分布及其环境特征

根据2003～2005年和2007年4月份在黄海南部和东海海域进行的底拖网调查数据,分析了小黄鱼产卵场分布和产卵场环境特征等.结果表明,目前小黄鱼产卵场范围较过去有扩大,范围已经扩展到外海海域,产卵场可分为黄海南部产卵场和东海产卵场;其中黄海南部产卵场主要集中在33°00′～34°00′N,122°30′～124°00′E,产卵场最适水温范围为9.65～12.17℃,最适盐度范围为32.25～34.54,最适水深范围为29.74～76.49m;东海产卵场主要集中在30°30′～31°00′N,124°00′～125°00′E海域和30°30′～32°30′N,125°00′～126°00′E海域,产卵场最适水温范围为10.13～16.64℃,最适盐度范围为32.50～34.37,最适水深范围为40.23～85.61m;黄海南部和东海产卵场水温分布差异极显著(P<0.01);小黄鱼产卵场较过去发生较大变化的主要原因可能是在过度捕捞等扰动因素的影响下,小黄鱼对环境适应性明显提高.     

金线鱼卵子和仔鱼的观察

金线鱼Nemipterus virgatus(Houttuyn)是南海产重要底层经济鱼类之一(广东省称红三、红衫,台湾省称金线鲢),属金线鱼科Nemipteridae,广泛分布于东海南部,南海北部,南沙群岛南部一带也是底拖网渔获物的重要组成部分。在04°00′—04°15′N,112°30′—114°26′E,5月中旬表层水温29.6℃时,在海上解剖肉眼观察结果,雌雄性腺都成熟。在北部湾分布也很密集,多栖息于水深40—70米处。南海北部多栖息活动在水深     

牯牛降自然保护区

牯牛降风景优美,景观独特,集“奇松、怪石、云海、佛光、飞瀑”五绝于一身。它位于安徽南部徽州地区的石台县与祁门县的交界之处,介于东经117°20′至117°37′,北纬30°00′至30°14′之间,其东能见黄山隐隐,北可望长江悠悠,是安徽大地上一颗神秘而璀灿的绿色明珠。 牯牛降,古代也曾称“黄山”或“西黄山”,     

南海北部台湾浅滩一带浮游动物数学模型的初探

南海北部台湾浅滩一带(21°30′—23°30′N,116°30′—118°30′E)不仅是上升流区也是南海暖水、黑潮及沿岸水互相交错的水域因而它是南海北部重要渔场之一。该水域每年5—9月是蓝圆鲹(Decoptera maruadsi)及金色小沙丁(Sardinella aurits)等中上层鱼类的旺汛期。浮游动物中不少的类群是上述几种鱼类直接捕食的对象,它与原始生产者互相制约也与水文状况中各种因素密切相关,因而对浮游动物与海况因子建立方程,可为渔情预报提供数学模型(亚模)。     

昆仑山北麓近30年来几种兽类的动态

昆仑山北麓,在行政区划上属新疆和田地区。据1965年钱燕文等的动物区划,隶属于蒙新区、西部荒漠亚区、塔里木盆地省的昆仑-阿尔金山北麓平原洲和皮山-民丰区(Ⅴ级区)。位于东经77°30′—85°00′,北纬34°20′—39°58′。     

Marine molluscs and fish as biomarkers of pollution stress in littoral regions of the Red Sea, Mediterranean Sea and North Sea

The intensive development of industry and urban structures along the seashores of the world, as well as the immense increase in marine transportation and other activities, has resulted in the deposition of thousands of new chemicals and organic compounds, endangering the existence of organisms and ecosystems. The conventional single biomarker methods used in ecological assessment studies cannot provide an adequate base for environmental health assessment, management and sustainability planning. The present study uses a set of novel biochemical, physiological, cytogenetic and morphological methods to characterize the state of health of selected molluscs and fish along the shores of the German North Sea, as well as the Israeli Mediterranean and Red Sea. The methods include measurement of activity of multixenobiotic resistance-mediated transporter (MXRtr) and the system of active transport of organic anions (SATOA) as indicators of antixenobiotic defence; glutathione S-transferase (GST) activity as an indicator of biotransformation of xenobiotics; DNA unwinding as a marker of genotoxicity; micronucleus test for clastogenicity; levels of phagocytosis for immunotoxicity; cholinesterase (ChE) activity and level of catecholamines as indicators of neurotoxicity; permeability of external epithelia to anionic hydrophilic probe, intralysosomal accumulation of cationic amphiphilic probe and activity of non-specific esterases as indicators of cell/tissue viability. Complete histopathological examination was used for diagnostics of environmental pathology. The obtained data show that the activity of the defensive pumps, MXRtr and SATOA in the studied organisms was significantly higher in the surface epithelia of molluscs from a polluted site than that of the same species from control, unpolluted stations, providing clear evidence of response to stress. Enhanced frequency of DNA lesions (alkaline and acidic DNA unwinding) and micronucleus-containing cells was significantly higher in samples from polluted sites in comparison to those from the clean sites that exhibited genotoxic and clastogenic activity of the pollutants. In all the studied molluscs a negative correlation was found between the MXRtr levels of activity and the frequency of micronucleus-containing hemocytes. The expression of this was in accordance with the level of pollution. The complete histopathological examination demonstrates significantly higher frequencies of pathological alterations in organs of animals from polluted sites. A strong negative correlation was found between the frequency of these alterations and MXRtr activity in the same specimens. In addition to these parameters, a decrease in the viability was noted in molluscs from the polluted sites, but ChE activities remained similar at most sites. The methods applied in our study unmasked numerous early cryptic responses and negative alterations of health in populations of marine biota sampled from the polluted sites. This demonstrates that genotoxic, clastogenic and pathogenic xenobiotics are present and act in the studied sites and this knowledge can provide a reliable base for consideration for sustainable development. Received: 2 March 1999 / Received in revised form: 2 August 1999 / Accepted: 3 August 1999     

The rotifer fauna of arctic sea ice from the Barents Sea,Laptev Sea [2pt] and Greenland Sea

Hydrobiologia - Samples from arctic sea ice were studied for their rotifer fauna. Ice core samples were collected in the northern Barents Sea and the Laptev Sea from August to October 1993 and in...     

Hydromedusae of the Mediterranean Sea

Mediterranean hydromedusae can be classified in several categories: common species, widely distributed throughout the Mediterranean and rare species reported from the Pacific, Indian or Atlantic Oceans; seasonal species comprising cold-season species with a boreal affinity and warm-season species with a hot to temperate affinity; neritic and mid-ocean species; surface species and meso-, infra-, and bathypelagic species. Holoplanktonic species are known to be associated with stable hydrological conditions (offshore waters, deep waters, summer and winter homothermy), whereas meroplanktonic species are more likely to be found in more disturbed hydrological conditions (coastal waters, surface waters, spring and autumn periods of temperature fluctuation). A general pattern of medusa distribution is established based upon comparative study throughout the Mediterranean.     

东海和黄海主要鱼类的食物竞争

以2000年和2001年在东、黄海两次大面调查所收集的、占总生物量90%的重要生物种类中的鱼类为研究对象,通过分析胃含物获得各饵料成分的重量百分比,用Pianka(1973)提出的公式计算的饵料重叠系数分析了东、黄海主要鱼类之间的食物竞争状况,以了解食物竞争与种群变动和优势种交替之间的相互关系。结果表明:黄海主要鱼类的食物竞争对象主要为太平洋磷虾、脊腹褐虾和,东海主要鱼类的食物竞争对象主要为太平洋磷虾、细条天竺鱼、发光鲷、、七星底灯鱼和带鱼。东、黄海鱼类通过摄食种类、摄食食物大小、摄食时间和栖息地的分化来减少食物竞争,从而维持群落结构的动态平衡。渔业资源群落结构的变化将导致食物竞争状况发生改变;鱼类食物竞争状况也会影响种群动态,但要确定食物竞争程度还需进一步深入研究     

黄渤海海水养殖自身污染的评估

探讨了投饵和非投饵两种养殖方式自身污染对海洋环境的影响.结果表明,海水养殖产量与营养盐类、COD和赤潮发生次数均呈正相关关系,其中无机氮含量和赤潮发生次数与虾养殖产量有显著正相关关系,说明海水养殖自身污染对邻近海域富营养化及赤潮发生有一定影响.通过黄渤海海水养殖向海洋排泄氮、磷、COD等污染物估算,分别占相应陆源污染物排海量的2.8%、5.3%、1.8%.虽然与人类其他活动向海洋排污量相比,水产养殖的排污量所占比重还不算大,对于某些局部水域,特别是海水养殖密集区,将对海洋环境的影响产生叠加作用,很可能成为刺激近海富营养化和赤潮发生的一个重要因素,应引起足够的重视.     

Seasonal variations of microphytoplankton assemblages and environmental variables in the coastal zone of Bozcaada Island in the Aegean Sea (NE Mediterranean Sea)

Seasonal changes in the microphytoplankton assemblages were examined in the coastal zone of Bozcaada Island with regard to some major physical and chemical variables. Samples were collected from May 2000 to December 2001 at four stations. A total of 108 dinoflagellates, 102 diatoms, 1 chrysophycean, 3 dictyochophycean, and 1 prasinophycean species were identified and quantified during the study period. Diatoms and dinoflagellates were the most important in terms of species number and abundance. The maximum values of total microphytoplankton were observed at 0.5 m depth (46.2 × 10³ cells l⁻¹ at st. 3) in May as this was the month when the diatom Pseudo-nitzschia pungens bloomed. Chlorophyll (chl) a concentration ranged between 0.08 (August) and 0.78 μg l⁻¹ (February). May was another important month in which chlorophyll a increased (0.41–0.47 μg l⁻¹). Species diversity values (H′_log2) ranged from 1.66 bits (June, 20 m) to 4.11 bits (November, 0.5 m). The increase was attributed to a more balanced distribution of abundance among species. The amounts of nitrate + nitrite (0.6−3.7 μg-at N l⁻¹), phosphate (0.2−0.6 μg-at P l⁻¹) and silicate (0.7−2.5 μg-at Si l⁻¹) were recorded on each sampling occasion. Nutrient concentrations and chl a values of the research area were found to be poorer than those of the many other coastal areas in the northeastern Mediterranean. The mean atomic ratio of nitrogen to phosphorus varied from 1.3 (June) to 12.9 (February). This ratio was lower than the Redfield ratio of 16 for ocean phytoplankton, and phytoplankton was potentially limited by nitrogen for most of the months. The result of this study confirms and emphasizes the oligotrophic nature of the eastern Mediterranean.     

Trace fossils as indicators of environmental change in Holocene sediments of the Archipelago Sea, northern Baltic Sea

Biogenic structures in Holocene sediments from the Archipelago Sea, northern Baltic Sea, were characterized through the analysis of X-ray images of four cores collected from water depths between 32 and 66 m. In the area, initial colonization of endobenthic invertebrates occurred at 7800 ± 80 calendar years BP. The trace assemblage at this level is low-diversity, small-diameter, shallowly tiered, and Palaeophycus-dominated; rare Arenicolites are also observed. Early colonization coincides with increasing marine influence in the post-glacial lacustrine setting just before the dramatic onset of brackish-water conditions established after 7600 BP. The post-incursion brackish-water assemblage possesses a higher diversity of traces (Planolites, Arenicolites, Lockeia, Teichichnus), which is taken to reflect the enhanced salinity and trophic state of the basin. The shift from Palaeophycus-mottling to a Planolites-dominated fabric represents changed behavioural patterns in the endobenthic community due to changed substrate properties. The ethology of the succeeding trace assemblage also represents a switch from domicile-based activities, such as predation, scavenging and interface-dominated deposit feeding to shallow-tier deposit feeding. Finally, traces are excluded from thinly laminated intervals, demonstrating that seafloor oxygen deficiency commonly reached levels that were detrimental to colonization of the sediment substrate.     

Biodiversity variability of macrobenthic in the Yellow Sea and East China Sea between 2001 and 2011

In this study, we compared the biodiversity and ecological status of macrobenthos between 2001 and 2011 in terms of species composition, dominant species, abundance, biomass, diversity, and secondary productivity of macrobenthos in the Yellow Sea and East China Sea. The results indicate that the species abundances, biomass, and diversity in spring 2011 were all lower than those in autumn 2000 and spring of 2001. Most of the dominant species have changed from 2001 to 2011, with the exception of the echinoderm Ophiura sarsii vadicola that was dominant in these years. Small-sized animal species have increased possibly due to gradual environment deterioration such as the pollution and the climate warmer.     

Fish assemblage structure in the East China Sea and southern Yellow Sea during autumn and spring

Based on bottom trawl surveys in autumn 2000 and spring 2001, the fish assemblage structure in the southern Yellow Sea and the continental shelf of the East China Sea was analysed. Four groups of fishes were identified for each season by the two-way indicator species analysis (TWIA). Although seasonal migration caused a slight difference in fish assemblages between autumn and spring, two major groups of fishes, corresponding to the Yellow Sea and East China Sea were identified. Inshore and offshore groups were subsequently separated. Changes in water depth may be most important in the separation of the groups in the offshore waters of the East China Sea. Temperature affected the groupings between north and south, particularly in the central part of the Yellow Sea. Here, the cold water mass affected the species composition which was low in diversity and different from the other areas.     

Universalizing the Law of the Sea in the South China Sea Dispute

This article argues that a resolution of the maritime disputes in the South China Sea must be based upon a universalist framework where the maritime interests of the world are upheld. The article discusses the universalist framework of the 1982 United Nations Convention on the Law of the Sea (UNCLOS) and the universalist approach taken by the Tribunal on 12 July 2016 in the South China Sea Arbitration regarding the extinguishment of a state's “exceptionalist” maritime claims and the adoption of strict criteria for the characterization of features at sea.