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111.
The finfish and shellfish resources were assessed quantitatively and qualitatively in regard to their abundance in creek waters
at three sites within a period of two years, from January 1999 to December 2000, in the western mangrove areas of Kachchh.
The catch rate varied from 0.69 to 6.99 kg h−1. It was low during monsoon (July to October), which could be due to the freshwater-flow-induced salinity reduction in all
the sites. Among 38 species recorded, 5 were shellfish and 33 were finfish. The spawning period of fishes was found to be
during summer and early monsoon period (May to August). Surface water temperatures varied from 17 °C to 37 °C. Salinity values
varied from 34 to 44 and the pH ranged between 7 and 8.9. Variation in dissolved oxygen content was from 3.42 to 5.85 mL L−1. The high fishery densities in these semi arid mangrove creek areas were recorded during monsoon and early winter season. 相似文献
112.
2007年6月对厦门东海域5个站位和晋江安海湾4个站位进行了小型底栖动物调查,分析了小型底栖动物的类群组成、密度和生物量.结果表明,从这两个海域样品中共鉴定出12个小型底栖动物类群,厦门东海域和安海湾自由生活海洋线虫分别占总数量的84.56%和98.19%.生物量组成和密度组成不同,厦门东海域多毛类(37.80%)、海洋线虫(33.32%)和底栖桡足类(18.64%)共同组成了小型底栖动物的生物量优势类群;安海湾生物量优势类群是由海洋线虫(67.64%)和多毛类(30.46%)组成.厦门东海域小型底栖动物的平均密度为72.67±10.21ind/cm^2,平均生物量为23.01±10.41μg/cm^2;安海湾的平均密度为31.48±45.58ind/cm^2,平均生物量为18.28±25.69μg/cm^2. 相似文献
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115.
岬间海湾平面平衡形态规律的研究是砂质海岸稳定与演变研究的重要内容.简要回顾了岬间海湾平面形态规律的研究进展,着重介绍了研究海湾平衡形态的五个模型.通过评述平衡形态模型的优缺点,指出机理分析和经验拟合相结合应该为以后海湾平面平衡形态规律的研究发展方向,并论述了我国岬间砂质海湾平面平衡形态研究的重要意义. 相似文献
116.
Air-sea carbon fluxes and their controlling factors in the Prydz Bay in the Antarctic 总被引:3,自引:1,他引:2
The Prydz Bay in the Antarctic is an important area in the Southern Ocean due to its unique geographic feature. It plays an important role in the carbon cycle in the Southern Ocean. To investigate the distributions of carbon dioxide in the atmosphere and surface seawater and its air-sea exchange rates in this region, the Chinese National Antarctic Research Expedition (CHINARE) had set up several sections in the Prydz Bay. Here we present the results from the CHINARE-XVI cruises were presented onboard R/V Xue/ong from November 1999 to April 2000 and the main driving forces were discussed controlling the distributions of partial pressure of carbon dioxide. According to the partial pressure of carbon dioxide distributions, the Prydz Bay can be divided into the inside and outside regions. The partial pressure of carbon dioxide was low in the inside region but higher in the outside region during the measurement period. This distribution had a good negative correlation with the concentrations of ehlorophyll-a in general, suggesting that the partial pressure of carbon dioxide was substantially affected by biological production. The results also indicate that the biological produetion is most likely the main driving force in the marginal ice zone in the Southern Ocean in summer. However, in the Antarctic divergence sector of the Prydz Bay (about 64°S), the hydrological processes become the controlling factor as the sea surface partial pressure of carbon dioxide is much higher than the atmospheric one due to the upwelling of the high DIC CDW, and this made the outside of Prydz Bay a source of carbon dioxide. On the basis of the calculations, the CO2 flux in January (austral summer) was -3.23 mmol/(m^2 · d) in the inner part of Prydz Bay, i.e. , a sink of atmospheric CO2, and was 0.62 mmol/(m^2 · d) in the outside part of the bay, a weak source of atmospheric CO2. The average air-sea flux of CO2 in the Prydz Bay was 2.50 mmol/(m^2 · d). 相似文献
117.
118.
海湾扇贝和栉孔扇贝的组织病理学观察 总被引:3,自引:0,他引:3
海湾扇贝和栉孔扇贝的外观症状主要是外套膜收缩、变色及鳃发黑。取外套膜、鳃、消化盲囊、直肠、性腺和闭壳肌等组织,切片,观察发现:在外套膜、鳃、消化盲囊、直肠和性腺的上皮细胞的胞质中有大量的黄褐色圆形小颗粒,病发严重的甚至发生组织糜烂,细胞变形、脱落。 相似文献
119.
Lee M. Ock Park S. Jin Kang T. Soon 《中国海洋大学学报(英文版)》2006,5(3):219-227
1Introduction GamakBay,anegg shapedseasurfaceareaofap proximately112km2,isasemi enclosedshallowwaterareawithameandepthof9mandhasbotheastandsouthchannelstoreceiveseawaterfromoutside(seeFig.1).Similarscalesoftidalwavesalmostsimultane ouslyenterorexitthrough… 相似文献
120.
1 IntroductionForthepast 1 5years,muchattentionofoceanographershasbeenfocusedontheroleofironinlimiting phytoplankton productivityinthehigh nutrient ,low chlorophyll(HNLC)regions.OnboardshipironenrichmentincubationshavebeencarriedoutinthethreewellknownHNLCregions :notablyequatorialPacificOcean ,subarcticPacificO ceanandSouthernOcean (seereferencesinTable 1 ) .Theinsituironenrichmentexper imentshavebeenaccomplishedintheequatorialPacific (IronEx1in 1 993 (Wells 1 994)andIronEx2in 1 996(… 相似文献