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1.
2010年5月,在湛江湾海域设立10个站点对大型底栖生物进行调查,分析湛江湾大型底栖生物的种类组成、生物量、栖息密度和生物多样性特征,并通过聚类(CLUSTER)和MDS排序对大型底栖生物群落进行划分。结果表明,调查海域共有底栖生物共7门112种,环节动物门、软体动物门和节肢动物门为湛江湾大型底栖生物的主要类群。生物量分布范围为0.93~98.20 g.m-2,其中软体动物门的平均生物量最高值。栖息密度分布范围为6.11~24.80 ind.m-2,其中以环节动物门(24.08 ind.m-2)和星虫动物门(22.22 ind.m-2)最高。该海域大型底栖生物群落物种较为丰富,但多样性差。根据Bray-Curtis相似性系数聚类分析和多维尺度排序分析结果,可将湛江湾大型底栖动物划分为4个群落。丰度生物量曲线(ABC)分析结果,湛江湾大型底栖生物受到严重的环境污染或者扰动,群落结构不稳定。与其他海域大型底栖生物种类数、生物量和丰度的比较分析结果,湛江湾的生物量和丰度偏低。  相似文献   

2.
北部湾海域浮游植物的种类组成与数量分布   总被引:1,自引:0,他引:1  
1998年2月至1999年5月在北部湾进行了5个航次的调查.结果共检出浮游植物382种(包括变种),主要优势种为细弱海链藻(Thalassiosirasubtilis)和小舟形藻(Naviculasubminusula).调查期间浮游植物细胞数量为43.5×104~283.6×104m-3,平均101.8×104m-3.北部海域的数量远高于南部海域,数量密集区均分布在北部近岸水域,南部和中部海域的数量分布则随季节的变化而变化.浮游植物细胞数量的季节变化较明显,以春季数量最大,多样性指数和均匀度则均以春季最低,秋季最高.  相似文献   

3.
In 2012, an artificial reef system was deployed in Xiangshan Bay, China, to enhance its fishery resources. To determine the effect of the artificial reef system on the demersal nekton assemblages, a beforeafter- control-impact study design was applied. Comparisons of assemblages from impact and control habitats revealed that the assemblage in the impact area had a gradual response to reef deployment. The assemblages in the impact and control areas changed in different ways after reef deployment. During the study period, total biomass, species richness and average body weight in the control area remained relatively stable, whereas there were significant increases in these indicators in the impact area. Responses to the reefs differed among nekton species, inducing assemblage succession in the reefs post-deployment. Sparus macrocephalus and Cynoglossus abbreviatus benefited most from reef deployment. Conversely, smallsized shrimp Palaemon gravieri showed a progressive decrease in biomass following reef deployment. Overall, the artificial reef system diversified the demersal nekton assemblage, enhanced the total biomass, and increased the proportion of large-sized species.  相似文献   

4.
根据 2 0 0 1年 11至 2 0 0 2年 1月间北部湾海域秋、冬季 2个航次的底拖网渔业资源调查资料 ,对北部湾海域甲壳类的种类组成及分布进行研究。本次调查共渔获虾类 2 4种 ,隶属于 6科 11属 ;蟹类 30种 ,隶属 9科 19属 ;虾蛄 9种 ,隶属 2科 6属。各种类沿水深和地理分布有明显变化 ,主要集中分布于湾中部水深 2 1~ 80m海域。  相似文献   

5.
The ecological province based on phytoplankton species composition is important to understanding the interplay between environmental parameters and phytoplankton species composition. The aim of this study was to establish phytoplankton species composition ecological pattern thus elucidate the relationship between environmental factors and the phytoplankton species composition in the ecological provinces. Phytoplankton samples were collected from 31 stations in Yellow Sea(121.00?–125.00?E, 32.00?–39.22?N) in November 2014. The samples were enumerated and identified with the Uterm?hl method under an optical inverted microscope-AE2000 with magnifications of 200 × or 400 ×. In the present study, a total of 141 taxa belonging to 60 genera of 4 phyla of phytoplankton were identified, among them 101 species of 45 genera were Bacillariophyta, 36 species of 11 genera were Dinophyta, 3 species of 3 genera were Chrysophyta and 1 species of 1 genera was Chlorophyta. The study area was divided into 4 ecological provinces according to an unsupervised cluster algorithm applied to the phytoplankton biomass. A T-S(Temperature-Salinity) scatter diagram depicted with data of water temperature and salinity defined by environmental provinces matched well with the ecological provinces. The results of Canonical Correspondence Analysis(CCA) indicated that the phytoplankton species composition was mainly correlated with temperature, salinity and silicate concentration in the studied area. A method of establishing ecological provinces is useful to further understanding the environmental effects on the marine phytoplankton species composition and the consequent marine biogeochemistry.  相似文献   

6.
In-situ measurements in Xiangshan Bay, the East China Sea, show that the duration of the rising tide is shorter than that of the falling tide around the bay mouth, while it becomes much longer in the inner bay. A finite volume coastal ocean model (FVCOM) with an unstructured mesh was applied to simulate the asymmetric tidal field of Xiangshan Bay. The model reproduced the observed tidal elevations and currents successfully. Several numerical experiments were conducted to clarify the roles of primary mechanisms underlying the asymmetric tidal field. According to the model results, the time-varying channel depth and nonlinear advection prefer shorter duration of the rising tide in Xiangshan Bay, while the time-varying bay width favors longer duration of the rising tide. The overtides generated by these two opposite types of nonlinear mechanisms are out of phase, resulting in smaller M4 amplitude than the sumfold of each individual contribution. Although the bottom friction as a nonlinear mechanism contributes little to the generation of overtide M4, it is regarded as a mechanism that could cause a shorter duration of the rising tide, for it can slow down the M2 phase speed much more than it slows down the M4 phase speed. The time-varying depth, nonlinear advection and bottom friction are dominating factors around the bay mouth, while the time-varying width dominates in the inner bay, causing the tidal elevation asymmetry to be inverted along the bay.  相似文献   

7.
Chen  Tiantian  Zhang  Yingxin  Song  Shuqun  Liu  Yun  Sun  Xiaoxia  Li  Caiwen 《中国海洋湖沼学报》2022,40(2):577-591
Journal of Oceanology and Limnology - Phytoplankton are central components of marine environments, and are major players in the production and respiration budgeting. However, their diversity and...  相似文献   

8.
红海湾水产养殖示范区水质综合评价   总被引:3,自引:0,他引:3  
红海湾是广东省非常重要的海水养殖示范区。为了维系和保护红海湾规模化水产养殖示范区的优良生态环境 ,1 997年 4月至 1 998年 1 2月对红海湾水域水质的时空变化趋势和质量状况进行了研究与评价。结果表明 ,红海湾海水综合质量总体上处于相对清洁水平 ,但浅海养殖区和长沙湾养殖区有机污染明显 ,分别达富营养化和高富营养化程度。DIN和IP是水质富营养化的主要因素 ,而石油类、Cu、COD是重点控制的优先污染物。  相似文献   

9.
【目的】研究大型海藻固碳及氮磷吸收潜能。【方法】分析硇洲岛岩礁带19种生物量大于50 g·m~(-2)自然生长的大型海藻固碳量、生产力和TOC,对比分析岩礁带和距岩礁带4 km处海域海水中无机氮和无机磷含量。【结果】褐藻门有3种,生物量、固碳量和生产力最大,分别为20 498 g·m~(-2),550 762 g·a~(-1),2 466 g·m~(-2)·a~(-1);其次是红藻门有11种,生物量、固碳量和生产力分别为17 547 g·m~(-2),138 194 g·a~(-1),1 872 g·m~(-2)·a~(-1);绿藻门有5种,生物量、固碳量和生产力分别为3 064 g·m~(-2),4 827 g·a~(-1),158 g·m~(-2)·a~(-1)。受人类活动影响最小的博贺兰岛礁区域海藻生物量、固碳量和生产力均为最大。19种海藻中12种海藻TOC超过30%,分别为衫叶蕨藻Caulerpa taxifolia (M.Vahl) C. Agardh、囊状法囊藻Valonia utricularis(Roth)C. Ag.[Conterva utricularis]、网球藻Dictyosphaeria cavernosa(Forssk.) Boerg、珊瑚藻Corallina sp.、拟鸡毛菜Pterocladiella capillacea (Gmelin)Santelices et Hommersand、紫杉状海门冬Asparagopsis taxiformis (Delile)、茎刺藻Caulacanthus ustulatus (Mertens) Kütz、新角石藻Neogoniolithon sp.、叉节藻Amphiroa sp.、半叶马尾藻Sargassum hemiphyllum (Turn.) var. chinensis C. Ag.、囊藻Colpomenia sinuosa(Mert.exRoth)、羊栖菜Hizikiafusiforme(Harv.)Setch。岩礁带海水中的无机氮和无机磷含量分别在0.17~0.20mg·L~(-1)和0. 007~0. 018 mg·L~(-1)之间,距岩礁带断面4 km左右海域的4个相应站位IN和IP含量分别在0.18~0.22mg·L~(-1)和0.016~0.022mg·L~(-1)间,均略高于岩礁区相应站位。大型海藻的生物量与岩礁带无机氮和无机磷间Pearson相关系数分别为-0.248和-0.155。【结论】19种大型海藻在硇洲岛岩礁带海区生态环境下具有良好的生长适应性,固碳能力强,对氮磷具有吸收作用。  相似文献   

10.
Mangroves are unique in their biodiversity,but studies on their meiobenthic biodiversity in China are scarce.Despite the importance of mangroves,little work has been done on the classification of nematodes in mangrove wetlands.Fujian Province is the most northern point of China’s natural mangrove distribution,and it is also one of the provinces with the earliest constructed mangrove forest.In this paper,two new free-living marine nematode species of Desmodoridae from the Xiamen mangrove wetlands in China are described.Metachromadora xiamenensis sp.nov.is characterized by a cylindrical body,and smooth head capsule set off from the rest of the body.The cuticle is finely annulated and thickened at the midbody.Lateral ridges run from the posterior end of the pharynx to the middle of the tail.The amphid foveae is loop shaped and opens at the top with a double contour amphidial,pharynx with bipartite cuticularized internal cavity.There are 18 tubular precloacal supplements and tail with three small protuberances.Molgolaimus euryformis sp.nov.is characterized by a relatively short and plump body with finely annulated cuticle,which is particularly obvious in the tail.The head is small and wide with intensive striates.The inner and outer labial sensilla are indistinct with short spicules and ventral apophysis,a gubernaculum with a block-shaped hook,a swollen conical-cylindrical tail and an absence of precloacal supplements.  相似文献   

11.
Understanding the factors that drive variation in species distribution is a central theme of ecological research. Although several studies focused on alpine vegetation, few efforts have been made to identify the environmental factors that are responsible for the variations in species composition and richness of alpine shrublands using numericalmethods. In the present study, we investigated vegetation and associated environmental variables from 45 sample plots in the middle Qilian Mountains of the northwestern China to classify different community types and to elucidate the speciesenvironment relationships. We also estimated the relative contributions of topography and site conditions to spatial distribution patterns of the shrub communities using the variation partitioning. The results showed that four shrub community types were identified and striking differences in floristic composition were found among them. Species composition greatly depended on elevation, slope,shrub cover, soil p H and organic carbon. The important determinants of species richness were soil bulk density and slope. No significant differences in species richness were detected among the community types. Topography and site conditions had almost equal effects on compositional variation. Nonetheless,a large amount of the variation in species composition remained unexplained.  相似文献   

12.
Set-nets are common alongshore fishing gear used in Haizhou Bay, which rely on flow to catch fish. The catch per unit effort(CPUE) of set-net is affected by spatial-temporal and environmental factors but no research has been conducted on this subject. In this study, we used generalized additive models(GAMs) to explore the influence of spatial-temporal and environmental factors on CPUEs of species aggregated, small yellow croaker(Larimichthys polyactis), and octopus(Octopus variabilis) based on logbooks investigations conducted at 4 stations in an alongshore area of Haizhou Bay from 2011 to 2012. The results showed that all CPUEs exhibited significant spatial-temporal differences at various scales. Aggregated CPUE was high when the sea surface temperature(SST) was 15-18℃ and 20-23℃, which was mainly determined by life history traits of the octopus and small yellow croaker(optimal SSTs 14-17℃ and 19-24℃, respectively). Chlorophyll-a concentration had significant influences on the aggregated, small yellow croaker and octopus CPUEs at optimal ranges of 3.8-6.2 mg m~(-3), 4.2-4.8 mg m~(-3) and 4.5-5.5 mg m~(-3), respectively. Flow through the net had positive relationships with CPUEs. The approximate logarithmic trends in regression curves had a critical point of 2.5 Mm~3 d~(-1), which was the dividing point that differentiated whether the major factor affecting CPUEs was the flow velocity or the fishery resource. Our results from this study will help guide fishery production and improve catch rate of set-net fishing in Haizhou Bay.  相似文献   

13.
【目的】评价北京北运河水系河流生态系统状态,分析底栖动物群落与环境因子之间的相关性。【方法】2015年6月对北京地区夏季北运河水系33个样点的大型底栖动物群落结构和水环境理化因子特征进行野外调查,基于香浓维纳指数、均匀度指数、底栖动物功能摄食类群的划分以及典范对应分析等方法,分析底栖动物群落组成和空间结构特征。【结果】共鉴定出底栖动物3门23种,各采样点位平均密度为1037.35 ind/L,香浓维纳指数平均值为0.88,均匀度平均值为0.41。全区大型底栖动物共划分成5类功能摄食类群,其中刮食者物种数占绝对优势,滤食者密度占绝对优势。典范对应分析表明,夏季影响北运河底栖动物功能摄食类群的主要环境因子是水温和p H。【结论】北运河水系底栖动物群落香浓维纳指数较低,水体污染较为严重。  相似文献   

14.
Attracting released hatchery-reared fish to designated areas during the growth process is vital to realize the objectives of sea ranching. Based on the bottom artificial reefs and surface kelp culture facilities in the Xiangshan Bay sea ranch, we proposed systematic techniques related to acoustic conditioning of the black seabream(Sparus macrocephalus). Experiments conducted in 12 m × 10 m × 1.6 m ponds on Xixuan Island showed that black seabream was positively sensitive to 500–600 Hz periodic signals. Conditioned responses were apparent after 8 d. Two to three days were required for recovery of the memory of a conditioned response after a 20-day interval. According to the practical application requirements in the open sea, unattended acoustic conditioning equipment was developed. The ranching equipment was used in 12 m × 12 m × 2.5 m cages, and the behavior of black seabream juveniles was successfully guided after 7 days. Of the 16000 released fish, 82.5% of them were conditioned with a flexible grading net. To avoid inducing a stress response, the juveniles were released into the sea ranch in situ from the net cage. The acoustic conditioning equipments were moved into the open sea and the aggregation phenomenon of the released fish was observed when the sound was played. After 6 months of investigation and based on Sr+ marking, only one acoustically conditioned fish was found outside the 3.5-km~2 sea ranch area, thereby reached the goal of guiding activity. The practical effect in the Xiangshan Bay sea ranch showed the validity of the acoustic conditioning system, which may contribute to improve the operation of the sea ranches in the East China Sea.  相似文献   

15.
【目的】分析湛江湾沉积物中氨氧化古菌(AOA)和氨氧化细菌(AOB)的丰度与多样性。【方法】采用分子生态学方法。【结果】AOA amoA基因丰度范围为3.23×10~5~5.27×10~6 copies·g~(-1)(以干土计),AOB amoA基因丰度范围为2.99×10~4~1.06×10~7 copies·g~(-1)(以干土计),两者平均丰度差别不大;但对于潮下带,大部分站位AOA amoA基因丰度高于AOB,且与氨氮和有机碳含量显著正相关。在工厂排污口和养殖区AOA多样性高于其他站位,而AOB则相反,说明AOA对环境污染物有更强的适应能力。系统发育分析显示,88%的AOA amoA序列属于海洋簇Group I.1a,优势类群是一类喜热带气候的AOA新分支;潮下带亚硝化螺菌属AOB为优势种群,而潮间带亚硝化单胞菌属AOB为优势种群。CCA分析表明,盐度和pH显著影响湛江湾AOA与AOB的群落结构。【结论】湛江湾沉积物中氨氧化微生物的分布与氨氮、总有机碳、盐度、pH等多种环境因子密切相关。  相似文献   

16.
To explore the spatial-temporal distribution of the phytoplankton community and evaluate the combined effects of marine resource exploitation, net-collected phytoplankton and physical-chemical parameters were investigated in the Xiangshan Bay during the four seasons of 2010. A total of eight phyla, 97 genera, and 310 species were found, including 232 diatom species, 45 dinoflagellate species and 33 other taxa. The phytoplankton abundances presented a significant (P<0.001) seasonal difference with the average of 60.66×104 cells/m3. Diatoms (mainly consisting of Coscinodiscus jonesianus, Cerataulina pelagica, Skeleto n ema costatum, and genus Chaetoceros) dominated the phytoplankton assemblage in all seasons. We found great spatio-temporal variation in community composition based on the multidimensional scaling and similarity analysis. Canonical correspondence analysis show that temperature, nutrition, illumination, and salinity were the main variables associated with microalgal assemblage. Compared with the previous studies, an increase in phytoplankton abundance and change in the dominant species coincided with increased exploitation activities in this bay (e.g. operation of coastal power plants, intensive mariculture, tidal flat reclamation, and industrial and agricultural development). The present findings suggest that the government should exercise caution when deciding upon developmental patterns in the sea-related economy.  相似文献   

17.
根据2010~2011年中街山列岛水域4个季节的渔业资源调查资料,分析了该水域虾类资源密度和群落多样性,并探讨了底层温度、底层盐度和水深对虾类数量分布和多样性的影响.结果表明:共有虾类20种,隶属于9科18属;广温广盐种无论在种类数还是尾数密度与生物量均占主导地位;虾类生物量和尾数密度在季节分布上,以冬季最高,冬季均与春、夏和秋三季呈显著差异(p值<0.05);平面分布上,生物量与密度指数总体上呈南北高、中间低,东部高西部低的特征;生物量与平均底温显著相关(P<0.05),与平均底盐和水深相关性较差(p值>0.05);葛氏长臂虾、细巧仿对虾、中国毛虾、日本鼓虾和中华管鞭虾为四季的优势种,且均属广温广盐种;虾类群落Margalef丰富度指数为0.61~1.09,Shannon-Wiener多样性指数为0.76~1.31,Pielou均匀度指数为0.50~0.70,其中丰富度指数和多样性指数春季与冬季均存在显著差异(P<0.05),均匀度指数秋季与冬季存在显著差异(p值<0.05).  相似文献   

18.
虾池浮游微藻的种类组成、数量和多样性变动   总被引:5,自引:1,他引:5  
报道了在集约化养虾中应用有益微生物制剂对虾池浮游微藻的影响,分析了整个养虾周期浮游微藻的种类组成、生物量、优势种及多样性指数的周期变化情况。结果表明,早期虾池浮游微藻细胞数量维持在1×103~3×103mL-1的水平,养殖中期开始呈指数增长状态,后期达到顶峰,并维持在70×103~160×103mL-1的水平,生物量比自然海区高。优势种类明显,前期为中肋骨条藻和伏氏海毛藻等硅藻类,后期则为绿球藻和栅列藻等绿藻类,水色及藻相呈良好状态,而不施加芽孢杆菌制剂的对照池则在后期出现较大比例的有害的蓝藻。虾池藻类多样性指数、均匀度指数和种类丰度均呈现前期高后期低的趋势,而优势度指数则相反,呈现前期低后期高的趋势。浮游植物的多样性指数为0.60~3.80,平均为1.88,均匀度指数为0.14~0.83,平均为0.45;种类丰度为0.80~2.46,平均为1.38;优势度指数在0.17~0.85,平均为0.41。多样性指数和均匀度均比粤东海域低,但优势度则甚高。  相似文献   

19.
调查北仑河口北岸竹山岛沿岸3条潮间带断面大型底栖动物的生态特征,共采集到大型底栖动物63种,其中软体动物29种,甲壳动物18种,多毛类12种,其他类4种。优势种为珠带拟蟹守螺(Cerithidea cingulata)、长腕和尚蟹(Mictyris longicarpus)、智利巢沙蚕(Diopatra chilienis)和艾氏活额寄居蟹(Diogenes penicillatus)。平均生物量为155.06 g/m2,平均栖息密度为343.8 ind/m2。香农-维纳多样性指数平均值为2.27,种类均匀度指数平均值为0.48,丰富度指数平均值为3.53。ABC曲线分析结果表明,3条断面的潮间带大型底栖动物均受到了中等程度的扰动。Ⅰ~Ⅲ断面的大型底栖动物污染指数(MPI值)分别为2.61、0.16和-17.08。该海域的潮间带环境受到了一定程度的人为活动干扰。  相似文献   

20.
The species composition and abundance of microzooplankton at 10 marine and five coastal stations(Hongdao,Daguhe,Haibohe,Huangdao and Hangxiao) in the Jiaozhou Bay(Qingdao,China) were studied in 2001.The microzooplankton community was found to be dominated by Tintinnopsis beroidea,Tintinnopsis urnula,Tintinnopsis brevicollis and Codonellopsis sp.The average abundance of microzooplankton was highly variable among stations.Specifically,the abundance of microzooplankton was higher at inshore stations and lower ...  相似文献   

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