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1.
2000年夏季南极普里兹湾及邻近海域浮游植物研究   总被引:5,自引:2,他引:3  
报道了2000年夏季(1月)在62°~69°S,70°30'~75°30'E的南极普里兹湾邻近海域浮游植物种类组成、丰度分布、叶绿素a浓度及其环境调控.结果表明,调查海区共有浮游植物4门33属65种、变种和变型.浮游植物平均细胞丰度为32.67×103个/dm3.浮游植物细胞丰度和叶绿素a浓度高值均出现在水体较稳定的近岸海湾和冰间湖及毗邻陆架,在大陆坡和深海区它们的值明显减小.浮游植物细胞丰度和叶绿素a浓度在0~50m水层最大,100m以下水层随深度的增加而减小.浮游植物丰度呈昼夜变化,在13:00丰度最高.浮游植物优势种为短菱形藻(Nitzschiacurta),占总丰度的24.8%.浮游植物种类组成和细胞丰度与浮冰和水团稳定性有关.经回归分析,浮游植物细胞丰度与水温、溶解氧成显著正相关,与无机磷(PO43--P)和无机氮(NO3--N)成显著负相关.  相似文献   

2.
The plate culture method using the two formulae for non-nitrogenous media was adopted in this investigation for the purpose of counting and isolating nitrogen-fixing bacteria distributed in the open sea. Sea water samples were collected at eighteen different stations in the region of Lat. 50°N–15°S along Long. 155°W and two other stations in the Pacific Ocean. In order to compare with those samples from the open sea, water samples were also obtained at four stations in Suruga and Sagami Bays. Nitrogen-fixing bacteria appear to be widely but very unevenly distributed at all depths in sea water, in numbers approximately ranging from nil to 104 per 100 ml of sea water, and denser vertical populations have been found in the area of Lat. 40°N and 5°N along Long. 155°W, even at depths from 2,000 to 3,000m. A conparatively denser population of bacteria was found in sea water from Suruga Bay and Sagami Bay. The bacteria associated with plankton were abundantly demonstrated, in numbers ranging from 106 to 108 per 1 ml settling volume of plankton, in many plankton samples collected at four stations in the southern parts of the Pacific Ocean. Almost all the bacteria isolated from the samples of blue green algal colonies,Trichodesmium, sp., were able to grow on nonnitrogeneous media.  相似文献   

3.
本研究分别于2019年7月(夏季)和12月(冬季)对澄迈马袅湾网箱养殖区及周边海域的大型底栖生物进行调查。结果表明,两次调查共采集鉴定到55种生物,其中夏季31种,主要分布在邻近区;冬季33种,主要分布在养殖区和邻近区。夏季航次,底栖生物在养殖区、邻近区和对照区的栖息密度分别为30.55 ind/m2、40.74 ind/m2和29.63 ind/m2,生物量分别为14.36 g/m2、6.28 g/m2、6.58 g/m2;冬季航次,三个海区底栖生物栖息密度分别为55.56 ind/m2、46.67 ind/m2和27.78 ind/m2,生物量分别为7.29 g/m2、6.20 g/m2和0.22 g/m2。夏季优势种主要为绒毛细足瓷蟹和纽虫;冬季优势种主要为豆形短眼蟹、梳鳃虫、纽虫和哈氏美人虾。夏季养殖区、邻近区和对照区大型底栖生物多样性指数(H′)分别为1.40、2.06和1.46;冬季分别为2.16、1.59和0.94。综上分析,网箱养殖产生的残饵和鱼类粪便,对养殖区及邻近海域底栖生物分布产生一定影响,且其群落结构与区域和季节存在较强相关性。  相似文献   

4.
From the Indian coast only limited data are available on the benthic fauna of the seagrass communities. In this study, seasonal variation in the distribution of macrobenthos and influence of environmental parameters was explored at four seagrass beds and two mangrove stations along the Minicoy Island, Lakshadweep, India, from September 1999 to August 2001. A total of 160 macrobenthic species from eight major groups represented the macrofauna of the Minicoy Island. Of the identified taxa, molluscs 70(gastropods 41.46%, bivalves 7.5%), polychaetes 27(16.88%), crustaceans 30(18.75%), echinoderms 11(6.88%) and remaining others. Average seasonal abundance of benthic macrofauna ranged from 219 to 711 ind./m2, species diversity varied from 1.45 to 3.64 bits per individual, species richness index ranged from 4.01 to 26.17, evenness 0.69 to 1.66. In general, the higher abundance and species diversity was noticed in southern seagrass stations and northern seagrass stations, but in the mangrove stations comparatively low species diversity was observed. Three-way analysis of variance indicated that all communities resulted as being significantly different between seagrass and mangrove station, mainly when the seasonal interaction was considered. Multivariate analyses were employed to help define benthic characteristic and the relationship between environmental parameters at the six monitoring stations. Results of cluster analyses and multidimensional scale plot suggest that for mangrove region, different physiographic provinces, lower salinity, dissolved oxygen and sediment biotic structure have a higher influence on the species composition and diversity than other oceanographic conditions.  相似文献   

5.
The S/V Shoyo, of the Hydrographic Department, Japan Coast Guard, has conducted high-density expendable bathythermograph (XBT) measurements along the 32.5°N line in the North Pacific every year from 1990 to 1993 as a part of the Japanese-World Ocean Circulation Experiment (WOCE). These XBT data are analyzed here, focusing on year-to-year variations of the inventory and core layer temperature (CLT) of the North Pacific subtropical mode water (NPSTMW). Large year-to-year changes are found in the NPSTMW CLTs estimated in longitudes between 140°E and 160°E. CLT values were found of 17.4°C in 1990, 17.1°C in 1991, 17.3°C in 1992 and 17.6°C in 1993. Inspection of the wintertime westerlies over the formation area and sea surface temperature distribution revealed that this change in CLT can be qualitatively attributed to the strength of atmospheric cooling in the formation area in the previous winter. Although a large year-to-year variation of NPSTMW inventory was also found, it is hard to state any relationship between CLT and atmospheric forcing. There is a possibility that different observational seasons may affect the inventory. It has also been found that the thermocline depth in 1991 was shallower in the sea area east of 180° than in 1992 and 1993. Associated with this change, the North Pacific central mode water (NPCMW), characterized by thermostad with temperatures ranging from 14°C to 11°C, appears in the sea area east of 180° in the 1992 and 1993 cross sections. The 1993 cross section, which ranged from the Japanese coast to the west coast of North America, possessed another thermostad in the surface layer, with a temperature of about 17°C in the eastern part of the cross section, off California. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

6.
2010年秋季南海北部浮游植物群落结构研究   总被引:5,自引:0,他引:5  
2010年10月26日-11月24日在南海北部进行了浮游植物群落结构的调查,共鉴定浮游植物4门70属204种(包括未定种12种),浮游植物以硅藻为主,其物种数为146种,其细胞丰度占总浮游植物细胞丰度的93.17%;甲藻次之,其物种数为51种,占总浮游植物细胞丰度的0.63%;金藻门3属4种及蓝藻门2属3种;蓝藻门中以红海束毛藻(Trichodesmium erythraeum)为主。调查区浮游植物的细胞丰度介于0.06×103~107.50×103 cells/L之间,平均值为5.00×103 cells/L。海南岛东北部和粤东近岸表层浮游植物丰度较高。垂直分布上,表层和25 m层的浮游植物细胞丰度较高。浮游植物主要优势种类有菱形海线藻(Thalassionema nitzschioides)、舟形藻(Navicula spp.)、中肋骨条藻(Skeletonema costatum)、旋链角毛藻(Chaetoceros curvisetus)、斯氏几内亚藻(Guinardia stolterforthii)、具槽帕拉藻(Paralia sulcata)等。调查区表层和5 m层Shannon-Wiener多样性指数平均值分别为3.14和2.83,Pielou均匀度指数平均值分别为0.73和0.77;两种指数在表层和5 m层均表现出较高的一致性。环境分析表明除硅酸盐外,浮游植物细胞丰度与其他环境因子均呈极显著性的相关性,主要受到氮元素及磷酸盐的共同限制作用。  相似文献   

7.
基于2011年3至5月对南黄海及长江口附近海域的水体与沉积物样品采集及实验室萌发培养实验,分析了绿潮暴发前期该海域微观繁殖体的时空分布特征。结果表明,在调查期间,南黄海水体中微观繁殖体空间分布趋势表现为近岸高远岸低,高值区主要集中在紫菜筏架养殖区附近海域,在122°30'E以东区域未发现有微观繁殖体存在。3,4,5月份该区域海水中平均微观繁殖体数分别为144 ,164和140株/dm3,最大值分别为278,426,和537株/dm3;南黄海沉积物中微观繁殖体数量分布范围介于19~127株/层,表层微观繁殖体数高于底层。长江口以北靠近江苏近岸区域有微观繁殖体存在,数量介于1~10株/dm3,31°N以南区域和河口内未发现有繁殖体分布,由此可排除黄海浒苔等绿藻微观繁殖体由长江水携带入海或来源于长江口南部海域。在春季绿潮暴发前开展该海域微观繁殖体的研究,可为查明绿潮发源地及早期发生发展过程提供基础资料,为预测和预警绿潮发生提供科技支撑。  相似文献   

8.
基于2011年3至5月对南黄海及长江口附近海域的水体与沉积物样品采集及实验室萌发培养实验,分析了绿潮暴发前期该海域微观繁殖体的时空分布特征。结果表明,在调查期间,南黄海水体中微观繁殖体空间分布趋势表现为近岸高远岸低,高值区主要集中在紫菜筏架养殖区附近海域,在122°30'E以东区域未发现有微观繁殖体存在。3,4,5月份该区域海水中平均微观繁殖体数分别为144 ,164和140株/dm3,最大值分别为278,426,和537株/dm3;南黄海沉积物中微观繁殖体数量分布范围介于19~127株/层,表层微观繁殖体数高于底层。长江口以北靠近江苏近岸区域有微观繁殖体存在,数量介于1~10株/dm3,31°N以南区域和河口内未发现有繁殖体分布,由此可排除黄海浒苔等绿藻微观繁殖体由长江水携带入海或来源于长江口南部海域。在春季绿潮暴发前开展该海域微观繁殖体的研究,可为查明绿潮发源地及早期发生发展过程提供基础资料,为预测和预警绿潮发生提供科技支撑。  相似文献   

9.
The uranium content and activity ratio A234U/A238U were determined in open ocean water, marine plankton, marine algae and sea water in the environment in which plankton and algae live. The average uranium content of 3.34±0.28×10−6 g/l and the average activity ratio of 1.13±0.04 were obtained in open ocean water. The uranium contents in plankton and algae were respectively from 1.7 to 7.8×10−7 g/g and 0.4 to 23.5×10−7 g/g on dry basis with the respective concentration factors of 48 to 260 and 10 to 733. The activity ratio in plankton and algae ranged from 1.07 to 1.18 which coincided well with those in the environmental sea water.  相似文献   

10.
夏季南海北部微型浮游动物群落   总被引:3,自引:1,他引:2  
根据2014年8月至9月于珠江口至南海中部断面(18°00'~22°00'N,114°00'~116°00'E)的南海北部海域进行采样调查,并进行了微型浮游动物群落分析。共发现微型浮游动物142种,隶属于2门44属,其中砂壳纤毛虫28属78种,占所有发现物种数的54.93%;寡毛类纤毛虫14属59种,占所有发现物种数的41.55%。优势类群为:拟卡金斯急游虫(Strombidium paracalkinsi)、具沟急游虫(Strombidium sulcatum)、维尔伯特急游虫(Strombidium wilberti)和无节幼体(nauplii)。调查区微型浮游动物的丰度介于11.43~959.35 ind/L之间,平均值为264.99 ind/L。微型浮游动物垂直分布总体特点是密集区位于50 m水层,50 m水层之下丰度逐渐减少。表层微型浮游动物丰度高值区位于J5-I1站位之间。断面的香农-威纳指数范围在0.92~4.18之间,平均值为2.77;均匀度指数在0.63~1之间,平均值为0.87。应用典范对应分析(CCA)发现温度和盐度是影响微型浮游动物群落的重要因素。通过对连续追踪站位的调查发现,上层水体微型浮游动物群落丰度随着时间而发生一定的变化,下层水体相对较平缓。微型浮游动物昼夜的垂直丰度变化与叶绿素浓度昼夜变化大致相符。  相似文献   

11.
刘玉 《海洋与湖沼》2013,44(2):292-298
选择珠江口南沙区两处典型的以大面积人工种植红树植物无瓣海桑(Sonneratia apetala)为主的感潮河涌,进行湿地区域中的浮游动物研究。于2011年5月和11月对开放性河涌湿地14涌(A区)和封闭性河涌湿地19涌(B区)中的浮游动物进行调研,从种类数和丰度、污染指示种和优势种、营养指数E和污染指数A等方面对浮游动物进行群落结构和功能的分析,并以此对湿地水质和无瓣海桑的净化能力进行评价。结果表明,B区林内原生动物总丰度可达106ind/L数量级,7种丰度优势种均为纤毛虫类,优势种哑铃中缢虫(Mesodinium rubrum),1种赤潮原生动物种类,单种丰度在春秋两季可达1.8×105ind/L、5.1×105ind/L。桡足类、枝角类在春季B区林内丰度最高,分别可达576ind/L和46ind/L,显示春季可能为其繁殖季节。轮虫相对不耐污染生境。指数E和指数A均远高于判断阈值。提出了二项浮游动物的富营养判断标准和二条原则。据此判断,B区湿地存在极重的有机污染现象,主要可能与无瓣海桑林内凋落物量较大或根系分泌物的作用且林内水流不畅有关。  相似文献   

12.
福建漳江口红树林保护区浮游植物群落的季节变化研究   总被引:4,自引:1,他引:3  
于2001年1月~2003年1月对福建省漳江口红树林区水体浮游植物群落的季节变化进行了研究。结果表明,漳江口红树林区浮游植物以硅藻门种类为主,优势种为长菱形藻(Nitzschia longissima)和菱形藻(Nitzschia sp.1)等,同时出现多种裸藻、绿藻和甲藻。本次调查共鉴定到浮游植物31属87种(包括变种),其中硅藻门23属75种(包括变种),蓝藻门3属3种,绿藻门1属4种,金藻门1属1种,甲藻门2属2种,裸藻门1属2种。浮游植物密度变化范围为2.78×104~1.14×106个/L,平均为3.51×105个/L,季节变化为双峰型。出现大量的底栖硅藻和淡水性藻类是该水域浮游植物的一个特点。浮游植物的组成和结构表明该水域水质较好。  相似文献   

13.
1982-2016年北极开阔水域变化   总被引:1,自引:0,他引:1  
李海丽  柯长青 《海洋学报》2017,39(12):109-121
近30年来,北极海冰覆盖范围大幅缩减,开阔水域也相应地发生显著变化。本文利用美国雪冰中心的海冰密集度产品以及美国海洋和大气科学管理局的海水表面温度数据产品,分析了1982-2016年北极开阔水域面积以及开阔水域季节长度的年际变化,并进一步探讨了海水表面温度对开阔水域时空变化的影响。结果表明北极开阔水域面积平均每年增加55.89×103 km2,海冰消退时间以平均0.77 d/a的速度在提前,海冰出现时间以平均0.82 d/a的速度在延迟,导致开阔水域季节长度以平均1.59 d/a的速度在增加。2016年达到了有遥感观测资料以来开阔水域面积和开阔水域季节长度的最大值,分别为13.52×106 km2和182 d。9个海区的开阔水域变化特征有一定的差异,对开阔水域变化贡献最大的有北冰洋核心区、喀拉海和巴伦支海。海水表面温度对开阔水域的变化有着重要影响,且影响的程度与纬度相关,即高纬度地区的海水表面温度对开阔水域的影响高于低纬度地区。  相似文献   

14.
The results of an investigation carried out during June 2005 to May 2007 on physico-chemical parameters,species composition and community structure of phytoplankton including Chlorophyll a(Chl-a) at the Coleroon coastal waters(Southeast coast of India) are reported.Air and surface water temperatures(°C) varied from 25.1 to 30.1 and from 24.5 to 28.5 respectively.Salinity values varied from 6 to 28.5 and the pH ranged between 7.0 and 8.3.Variation in dissolved oxygen content was from 3.1 to 7.5 mg/dm-3 while the light extinction coefficient values(LEC) ranged between 3.1 and 10.1 cm.The ranges of inorganic nutrients(μmol/dm-3) viz.,nitrate,nitrite,phosphate and silicate were 10.1-23.4,1.2-8.9,0.2-3.1 and 55-125,respectively.The ranges of Chlorophyll a(μg/dm-3) values was 2.0-7.5.Presently,124 phytoplankton species representing different classes viz:Bacillariophyceae(77),Dinophyceae(19),Cyanophyceae(15),Chlorophyceae(10) and Chrysophyceae(3) were recorded.The phytoplankton cell abundance varied from 0.290 to 111.662 cells/cm-3,with peak diversity(3.38 bits/ind.) during summer season.The maximum abundance was found during summer season coinciding with the stable hydrographical conditions.The seasonal distribution and abundance of phytoplankton are discussed in relation to hydrographical parameters.Canonical Correspondence Analysis(CCA) was applied in this paper for discriminating environmental factors having effect on phytoplankton community at species level.Coleroon coastal water is subjected to long term fluctuations in physico-chemical parameters depending upon the seasonal tidal amplitude and freshwater influx resulting in a continuous exchange of organic,inorganic,plant and animal matters.  相似文献   

15.
秦皇岛海域浮游植物的群落结构特征   总被引:1,自引:0,他引:1  
2014年4~9月对秦皇岛海域进行了调查,共鉴定出浮游植物3门33属70种,以硅藻门为主,7、8月份浮游植物种类数最多,约40种。在整个调查期间,浮游植物丰度在不同站位和月份之间差异较大,平均值为2.42×108个/m3,浮游植物优势种有北方娄氏藻、尖刺拟菱形藻、丹麦细柱藻、微小原甲藻等,优势种种类数9月最多,6月最少。浮游植物多样性指数为1.27~3.6,均匀度为0.31~0.73,6月份群落结构较单一,其他月份群落结构较稳定。  相似文献   

16.
为了解洞头列岛及邻近海域大型底栖动物的群落结构特征,于2015年4月在该海域布设35个站位进行大型底栖动物调查采样,并获取相关环境资料,分析了该海域大型底栖动物的群落结构及其与环境因子的关系。共鉴定出大型底栖动物122种,其中多毛类57种,甲壳动物34种,软体动物19种,棘皮动物5种,其它类动物7种。各调查站位大型底栖动物物种数目在1~22种之间,瓯江口附近站位物种数较少。大型底栖动物平均生物量为3.35 g/m2,平均栖息密度为321个/m2。多毛类具有种数上的优势,软体动物具有生物量和密度上的优势。Shannon-Wiener多样性指数、Margalef丰富度指数和Pielou均匀度指数的平均值分别为1.29、2.45和0.66。通过聚类分析和多维尺度排序分析将该海域大型底栖动物划分为3个群落:异蚓虫-薄云母蛤-绒毛细足蟹-不倒翁虫群落(群落Ⅰ),薄云母蛤-异蚓虫-双鳃内卷齿蚕-不倒翁虫群落(群落Ⅱ)和其他群落(群落Ⅲ)。典范对应分析表明,影响大型底栖动物群落的主要环境因子有底层海水的温度、盐度、活性磷酸盐、活性硅酸盐、溶解性无机氮、化学需氧量以及表层沉积物中的总有机碳等。ABC曲线分析结果表明,大型底栖动物群落受到了一定程度的扰动,但基本稳定。与历史资料相比,大型底栖动物的栖息密度和生物量均无明显变化,种类组成由以多毛类和软体动物为主转变为以多毛类和甲壳动物为主,且个体较大的棒锥螺大量死亡。  相似文献   

17.
The stable isotopes of organic carbon (OC) and nitrogen, contents of OC and nitrogen for roots, bark, leaves, flowers and fruits of various mangrove species from Kisakasaka (Zanzibar) and Bagamoyo (mainland Tanzania) are used to assess (1) if some mangrove species are capable of fixing atmospheric nitrogen, (2) if there are differences between species in the same stand and in different stands and (3) if the mangrove signature is preserved in the sediments. Mean OC stable isotope results of various plant components range from −25.9‰ to −29.1‰ suggesting that mangrove trees in the two stands follow the C3 type of photosynthetic pathway. Mean nitrogen isotope values for various plant components range from −1.5‰ to 3.2‰ suggesting atmospheric nitrogen fixation by mangrove plants, but δ15N values approaching −3‰ that are more negative than typical diazotroph biomass exclude this possibility. Mangrove species thriving further inland are enriched in 13C and 15N relative to those thriving near the shoreline owing to complete utilization of available nutrients.Sediments beneath the mangrove forest are characterized by lower C/N ratio values and enrichment in 13C and 15N relative to plant material owing to mixing of nitrogenous rich material from adjacent area. High concentration of OC is found in bark and roots, while high nitrogen concentration is found in fruits and flowers only.  相似文献   

18.
《Marine Chemistry》1987,21(3):203-211
Seawater samples and airborne particulate material were collected in the subtropical North Atlantic during R.V. “Meteor” Cruise M60 (N34°47.2′W26°57.7′/N10°1.3′W32°58.3′). Hydrocarbon concentrations were estimated in the samples. For seawater the concentrations ranged from 0.2 μg to 3.5 μg dm−3. In the open ocean air the concentrations of the particulate hydrocarbon measured at 14m above sea level ranged from 2.8 ng to 133.1 ng m−3. A significant increase was observed during a Saharan dust outbreak. Comparison with aluminium concentrations in seawater and in the air suggests input of atmospheric hydrocarbons by dry deposition to be an important transportation pathway.  相似文献   

19.
研究了南麂列岛海洋自然保护区浮游植物物种组成、数量分布、多样性指数及其与营养盐、浮游动物的关系.经鉴定,共发现浮游植物86种,隶属于33属.网样浮游植物平均密度为194.00×104个/m3,水样浮游植物平均密度为4.98×104个/m3,优势类群有角毛藻(Chaetoceros sp.)、角藻(Ceratuym sp.)、中肋骨条藻(Skeletonema costatum)、红色裸甲藻(Akashiwo sanyuineum)等.网样浮游植物多样性平均指数为2.28,水样浮游植物多样性平均指数为2.17.根据浮游植物组成特点,将其分为两个生态类群:近岸性和广布性类群,外海性类群.  相似文献   

20.
2001/2002年夏季南极普里兹湾及其邻近海域的浮游植物   总被引:15,自引:4,他引:15       下载免费PDF全文
报道了 2 0 0 1 /2 0 0 2年夏季南极普里兹湾邻近海域 3 7个大面测站浮游植物的调查结果。经初步鉴定共有浮游植物 3门 3 7属 86种 ,其中硅藻在种类和细胞丰度上占绝对优势 ,其次为甲藻。主要优势种为克格伦拟脆杆藻 (Fragilariopsiskerguelensis)、细条伪菱形藻 (Pseu do nitzschialineola)、短拟脆杆藻 (Fragilariopsiscurta)和赖氏束盒藻 (Trichotoxonreinboldii)等南极特有种类和常见种类。调查区浮游植物分为两个群集 ,分布在 6 7°S以南的普里兹湾内的群集主要以克格伦拟脆杆藻、短拟脆杆藻、胡克星脐藻 (Asteromphalushookeri)和南极弯角藻 (Eu campiaantarctica)等南极特有种类和常见种类为主 ;分布在 6 7°S以北的大洋海域的群集主要以细条伪菱形藻、赖氏束盒藻、拟膨胀伪菱形藻 (Pseudo nitzschiaturgiduloides)和羽状环毛藻(Corethronpennatum)等南极常见种为主。调查区浮游植物的平均细胞丰度为 (8796± 2 92 85 )ind/L ,细胞多分布于海水的表层 ,密集区分布在 6 7°S以南的普里兹湾内 ,浮游植物的细胞丰度同硝酸盐的浓度密切相关。调查区浮游植物的多样性程度是低的。  相似文献   

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