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31.
Variation of reactivity of particulate and sedimentary organic matter along the Zhujiang River Estuary 总被引:3,自引:0,他引:3
To investigate organic matter source and reactivity in the Zhujiang River (Pearl River)Estuary and its adjacent areas, particulate organic carbon (POC), particulate hydrolysable amino acids (PHAA), and Chl a during two cruises in July 1999 and July 2000 were measured. The highest POC and PHAA concentration was observed in the waters with maximum Chl a. The spectra distribution,relative content (dry weight in milligram per gram), PHAA-C% POC and other indicators such as the ratios of amino acids vs. amino sugars (AA/AS) and glucosamine vs. galactosamine (Glum/Gal) suggested that particulate amino acids in the water column and sediments in the Zhujiang River Estuary were mainly derived from biogenic processes rather than transported from terrestrial erosion. In inner estuary where high turbidity was often observable, organic matter was mainly contributed by re-suspension of bottom sediments with revealed zooplankton, microbial reworked characteristics, which suggest that these organic matters were relatively “old“. In the estuarine brackish region, organic matter in water column is mainly contributed by relatively fresh, easily degradable phytoplankton derived organic matter.During physical - biological processes within the eastuary, organic matter derived from phytoplankton was subjected to alteration by zooplankton grazing and bacterial reworking. 相似文献
32.
Stephen R. Wing Louis W. Botsford Lance E. Morgan Jennifer M. Diehl Carolyn J. Lundquist 《Estuarine, Coastal and Shelf Science》2003,57(5-6):859-872
We investigated sources of inter-annual variability in larval supply to crab and sea urchin populations at Bodega Head and Point Reyes in northern California. During the spring and summer upwelling seasons of the years 1992 through 1997 we monitored the weekly settlement rates of nine species of crabs and two species of sea urchins. As observed in previous studies, daily values of alongshore windstress, temperature and salinity provided evidence for the poleward flow of relatively warm, low salinity water from south of Point Reyes, an apparent retention zone, during upwelling relaxation events. In years dominated by these events (1992, 1993, 1995 and 1996) we observed that alongshore windstress, temperature and salinity were coherent and temperature was significantly correlated with cancrid crab settlement. During these years the magnitude of cancrid crab settlement and the fraction of cancrid crabs relative to other crab species settling were high. Over four years of concurrent sampling there was consistently greater cancrid crab settlement at the Point Reyes site, within the retention zone, than at Bodega Head. Settlement of non-cancrid crabs (porcellanids, grapsids, pagurids and majids) was not as closely linked to intra-annual patterns of upwelling and relaxation, possibly due to the shorter seasonal availability of larvae allowing for the influence of fewer relaxation events. Settlement of this group among years was positively correlated with environmental indicators of strong seasonal upwelling; high salinity, Bakun upwelling index and low temperature. Sea urchin settlement events were observed in June and July of 1992, 1994 and 1997 during warming periods when salinity and temperature were increasing and alongshore windstress was low. Across the six years of the study, we found that cancrid crab larvae had a more even seasonal availability than larvae of non-cancrid species, which settled in greatest numbers during the early portion of the upwelling season. Sea urchins settled in greatest numbers during the later part of the upwelling season. Together these patterns demonstrate the taxon-specific way that inter-annual variability in larval supply is forced by the coincidence of larval availability with favorable physical transport mechanisms. 相似文献
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九龙江河口区水体中的226Ra和228Ra 总被引:8,自引:0,他引:8
用MnO2-纤维富集大体积水样中的Ra同位素,并用直接射气法测定226Ra和228Ac的β计数法测定228Ra的方法,研究了九龙江河口区226Ra,228Ra的行为,结果表明:在该河口区226Ra,228Ra均呈非保守行为,226Ra,228Ra的最高值分别在盐度为19和9处测得。228Ra/226Ra)A.R.值在盐度小于19的区域约为3左右。与世界其他河口区相比,九龙江河口区的226Ra,22 相似文献
35.
One new species of free-living marine nematodes (Enoplida,Anticomidae, Cephalanticoma) from the Huanghai Sea 总被引:1,自引:0,他引:1
One new species of free-living marine nematodes Cephalanticoma filicaudata sp. nov. from the Huanghai Sea, China is described and illustrated. Cephalanticoma filicaudata sp. nov. is characterized by well developed cephalic capsule, three teeth at the anterior of oesophagus, excretory pore opens posterior to cervical setae, only two cervical setae per file, body length longer than 5 200 μm, tail long and no ventral-lateral seta between the supplement and the cloacal opening. Types are deposited in the College of Marine Life Sciences, Ocean University of China. 相似文献
36.
海洋生态环境监测的指标体系研究 总被引:1,自引:0,他引:1
本文在总结国内外各种海洋生态监测方法的基础上,构建生物分布指数、生物暴露指数和生物反应指数,并由此确定生态质量总指教。生态质量总指数可以综合反映特定海洋环境的生物群落特征,典型污染物在生物体内的蓄积特征以及生物体对环境污染的生理生化反应特征,因此可以应用于近岸海洋环境质量的生态监测。 相似文献
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39.
Species composition and distribution of marine nematode community in the North Taiwan Strait 总被引:9,自引:4,他引:9
Cai Lizhe Hong Huasheng Zou Chaozhong Fang Shaohu L Xiaomei Zhang Yueping 《海洋学报(英文版)》2001,20(2):221-229
I~IOW~ne nelnatode is a ban gIOup of benthic OrgAnsrns. Abbot 5 000 spotes Of free-livingnelnatedes have ben dedbo so far, and it has ho estimated that abbot 20 (XX) are as yetunknoWn. Chinese bothologist has Paid attention to marine nelnatodes in China seas in yare. The spatial distribution and shoes commotion of marine nelnatedes in the HUanghe EstUary, Qinhuangdao waters, QingdaO Bay and Xiamen ~ have ho reported (Zhang etal., 1990, 1991, 1993; ac and Li, 1998). ~ new shoes in the… 相似文献
40.
研究扇贝外套腔内栖生的纤毛虫一蠕状康纤虫Cohnilembusverminus(Muller,1786)的形态、核器及纤毛图式。结果显示其口器结构为;M1呈单列结构,约占体长的1/2,M2由4组毛基粒构成,PM起自M2末端,Sc约由5个毛基粒构成。此外,还列表比较了不同作者报导的C.verminus种群及其它6种已知的康纤虫的主要性状特征。 相似文献