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1.
《海洋地质与第四纪地质》2015,(2)
类脂生物标志物已被广泛用于重建海洋浮游植物生产力及群落结构变化,但是,在北黄海和渤海的应用还不多。在210Pb定年的基础上,对北黄海西南部箱式柱状样B25进行了生物标志物分析,利用其含量及相对比例变化重建了北黄海过去130年来浮游植物生产力及群落结构变化,并探讨了其变化规律对气候变化和人类活动的指示作用。结果表明:过去130年来,浮游植物生产力总体呈上升趋势,在1975年后显著增加。揭示了一种在我国边缘海群落结构变化的新特征,在1965—1990年间呈现硅藻比例下降和甲藻比例增加,而1990年之后则表现为硅藻比例增加和甲藻比例下降。北黄海近百年来浮游植物生产力的提高主要与东亚冬季风的增强和陆源输入增加有密切关系,而群落结构的改变可能是人类活动和气候变化共同作用的结果。 相似文献
2.
东海和黄海表层沉积物生物标志物的分布特征及古生态重建潜力 总被引：6，自引：0，他引：6
多参数生物标志物法已被广泛用于重建浮游植物生产力和种群结构.但目前还缺乏这一应用的现代证据,尤其是西太平洋边缘海地区.文中作者对东/黄海的表层沉积物中的浮游植物生物标志物的分布进行研究,发现东海表层沉积物中菜子甾醇、甲藻甾醇、长链烯酮的总含量变化范围为357～3 115 ng/g,黄海的总含量变化范围为2 898 ～6 714 ng/g,硅藻、甲藻和颗石藻生物标志物总量基本具有近岸高、离岸低的趋势,与现场调查资料所得到的趋势基本一致.生物标志物比例结果显示在东海的长江口方向离岸越远硅藻相对比例下降,而在长江口以南则是离岸越远硅藻比例升高.在东海和黄海颗石藻所占比例都很低,但是有离岸越远比例升高的趋势.用生物标志物所重建的种群结构的变化趋势与现场调查资料相符,但其绝对值却与现场资料存在差异.本研究为生物标志物重建种群结构提供了现代数据,但是此方法的定量应用还需做进一步的研究. 相似文献
3.
类脂生物标志物重建近150年来东海陆架区DH5-1站位浮游植物生态结构及陆源输入的变化 总被引：2，自引：0，他引：2
类脂生物标志物法已被广泛应用于古海洋环境研究,但是在东海利用类脂生物标志物法重建浮游植物生产力、群落结构以及陆源输入的研究还很缺乏。本文选取东海陆架区的DH5-1岩芯进行类脂生物标志物分析,利用各种类脂生物标志物的沉积通量及相对比例重建了东海陆架区近150a来浮游植物生产力和群落结构以及陆源输入的变化。结果表明:(1)DH5-1站位的浮游植物生产力在过去80年呈上升趋势,群落结构在过去近百年有甲藻比例升高,硅藻比例降低的趋势,而颗石藻比例在低值范围波动;(2)用于指示生活污水污染的两种指标(粪醇含量,粪醇/(粪醇+二氢胆固醇)比值)的值都很低,表明近150a来此站位基本未受人类生活污水污染;(3)陆源高等植物输入在1970年前是增加的,1970年后输入减少,陆源有机质指标TMBR指示近150a来陆源输入相对海源是减少的。DH5-1站位生产力的提高可能与长江冲淡水营养盐的增加和东亚冬季风的增强有关,群落结构的改变可能与近年来冲淡水的Si/N降低有关,研究区域40年来陆源有机质相对比例的减少主要与人类建坝活动增强有关。 相似文献
4.
随着人类活动的增加和全球气候变化的加剧,东海生态环境受到了人类活动和自然环境变化的双重影响。本文选择位于东海长江口泥质区的柱状样DH3-1进行生物标志物分析,利用多种生物标志物含量及相对比例重建了东海近30年(1983-2010年)浮游植物生产力、群落结构和陆源输入相对贡献的变化,并探究人类活动与自然因素产生的综合影响。结果表明:近30年来,浮游植物生产力呈现上升趋势;约1992-2001年,硅藻比例下降、甲藻比例上升,约2001年后硅藻比例上升、甲藻比例下降。陆源有机质含量在约1992-2004年呈现增加趋势,约2004年后相对降低;海源有机质含量则呈现持续增加趋势。东海近30年来浮游植物生产力的升高主要是因为人类活动剧增与上升流引发东海营养盐输入量增加。群落结构与陆源有机质含量交替变化可能是由不同年份人类活动与自然因素的作用强度不同导致的。 相似文献
5.
北黄海-渤海表层沉积物中浮游植物生物标志物的分布特征及指示意义 总被引：1，自引：0，他引：1
作为一种新的地球化学指标方法,多参数生物标志物法已被广泛应用于重建浮游植物生产力及群落结构。本文对北黄海-渤海表层沉积物中浮游植物生物标志物的分布进行了研究。通过对北黄海-渤海60个站位的调查研究发现,硅藻、甲藻和颗石藻这3种浮游植物的生物标志物含量高值区主要分布在泥质区,同TOC的分布模式类似。为了消除粒度和沉积速率对含量的影响,将这3种生物标志物含量分别与TOC做比值,结果发现相对含量高值区与高生产力区相对应。以这3种生物标志物的相对比例来分别指示浮游植物在北黄海-渤海的相对贡献变化,结果表明近岸区硅藻相对贡献高,这主要与硅藻在高浓度硅的情况下具有竞争优势有关;而由于对营养盐的竞争关系,甲藻相对贡献高值区处于远岸区。在北黄海中部发现高的颗石藻相对贡献,与黄海暖流入侵路径相对应。 相似文献
6.
浙江近岸泥质区百年来浮游植物生产力的变化及对环境的响应 总被引：2，自引：0，他引：2
在210Pb定年的基础上, 对取自浙江沿岸泥质缺氧区的柱样沉积物开展了菜子甾醇、甲藻甾醇、长链烯酮等生物标志化合物分析, 根据生物标志化合物含量及比例的分布特征, 重建了泥质区110年来浮游植物生产力及群落结构变化。结果表明浙江近岸浮游植物生产力百年来呈上升趋势, 自20世纪60年代开始上升, 80年代以来有显著增加, 浮游植物群落结构则均有甲藻比例上升、硅藻比例下降的趋势。研究认为, 浙江沿岸泥质区百年来浮游植物生产力的提高与我国化肥施用量和长江氮的入海通量呈正相关, 营养盐N∶P和N∶Si比值的增加导致浮游植物优势种由硅藻向甲藻的转变, 说明自20世纪60年代, 尤其是自20世纪80年代以来工农业快速发展、大型水利工程建设等人类活动是导致浙江沿岸泥质区海域浮游植物生产力提高及群落结构变化的主要因素。 相似文献
7.
多参数生物标记物法已被广泛用于重建浮游植物生产力和种群结构,研究了2003年夏季我国二次北极考察时采集的楚科奇海表层沉积物样品中浮游植物生物标志物的比例变化及其作为浮游植物种群结构替代指标的潜力。观测海区表层沉积物中菜子甾醇、甲藻甾醇、长链烯酮的总含量为20~3149 ng/g,平均值为1 010 ng/g,生物标志物总量分布表明南部的楚科奇陆架海域生产力明显高于北部海台区,不同站位的菜子甾醇和甲藻甾醇相对比例有明显变化,但都显示菜子甾醇占优势,楚科奇海陆架的站位中都是硅藻为主,菜子甾醇占生物标志物总量的比例为42%~74%,甲藻甾醇占生物标志物总量的比例为17%~37%,在海台区仍然是硅藻占优势,但是甲藻和颗石藻的比例有了很大的提高,加拿大海盆的4个站位中以甲藻和颗石藻为主,硅藻并非加拿大海盆的优势种群。这与用显微镜下鉴定得到的硅藻和甲藻分布趋势相似。研究结果为生物标志物作为浮游植物种群结果替代指标并为利用柱状样中的生物标志物研究古生态提供现代依据。 相似文献
8.
末次冰盛期以来日本海浮游植物生产力和群落结构变化 总被引：2，自引：0，他引：2
生物标志物法已经被广泛应用于重建海洋浮游植物生产力和群落结构变化。本文利用这种方法重建了日本海末次冰盛期以来浮游植物生产力和群落结构变化。结果显示,生物标志物含量在末次冰期最盛期21～19 ka和14～4 ka时有高值,而在19～14 ka、4～0 ka有低值。末次冰期最盛期时生物标志物的高含量是由于分层导致的底层水缺氧,生物标志物得到较好保存的结果,而此时日本海盐度很低,使颗石藻相对含量很低;19～14 ka陆源输入减少,日本海生产力水平较低,不断增加的盐度使浮游植物群落结构由硅藻、甲藻占优转变为颗石藻占优;14～4 ka对马暖流流量的加大提高了日本海的初级生产力,同时高营养盐利于硅藻、甲藻的生长,使颗石藻的相对比例减小;4 ka以后随冬季风的增强和黑潮减弱,对马暖流减弱,供应的营养盐减少,日本海生产力水平降低,使颗石藻的相对比例增大,硅藻、甲藻的相对比例减小。 相似文献
9.
生物标志物已被广泛应用于重建浮游植物生产力和群落结构变化.该方法假设之一是生标的含量可以反映表层海水的浮游植物生物量,但这个假设还缺乏现场观测的充分验证.对2009年冬季南海北部表层海水颗粒物中主要生标做了分析,利用其含量及比值研究浮游植物的生物量及群落结构的分布.生标含量表明硅藻、甲藻、颗石藻的高值区位于珠江口南部及广东沿岸,在陆坡区也有高值.生标比值显示硅藻在3个类群中的相对比例最高.其中,甲藻/硅藻比值高值区位于陆坡区,这与大洋水(黑潮)的入侵,带来大量暖水性甲藻有很大关系;颗石藻/硅藻比值总体趋势与生物量的分布相反,在近岸少数站位有高值,向外海逐渐增加,主要是因为颗石藻更适于寡营养盐的环境.生标结果所指示的生物量及群落结构的空间分布与前人的调查结果类似,为利用生标重建此区域的浮游植物生产力和群落结构变化提供了依据. 相似文献
10.
对渤海辽东湾海域表层沉积物中浮游植物生物标志物的分布进行了研究。通过对辽东湾51个站位的调查研究发现,硅藻、甲藻和颗石藻这3种浮游植物的生物标志物含量分布规律不明显,为了消除粒度和沉积速率的影响,将这3种生物标志物总量与总有机碳(TOC)含量做比值,得到的相对含量从湾内到湾口随着离岸距离增加而增加,生物标志物指示的初级生产力与现场调查的结果一致,表明生物标志物法基本可以用来重建初级生产力。辽东湾海域初级生产力在湾口高于湾内,表明其主要控制因素是水体浊度而不是陆源营养盐的输入。辽东湾西侧菊花岛附近初级生产力的高值主要与人类养殖、陆源排污等导致的水体富营养化相关。生物标志物的相对比例结果显示,辽东湾两侧近岸区硅藻和甲藻相对贡献高,尤其是硅藻占据绝对优势,这主要与硅藻在高营养盐的情况下具有竞争优势有关,而在辽东湾中部发现高的颗石藻相对贡献与黄海暖流入侵路径相对应。 相似文献
11.
Biomarkers had been widely used to reconstruct phytoplankton productivity,and this method was applied in the East China Sea and the Huanghai Sea (Yellow Sea).In this study,Biologic Silicon (BSi) was used as productivity proxy to reconstruct productivity change of phytoplankton during last 200 years.The results show that the BSi contents of surficial sediments were in the range of 0.018%-2.516%,averaging 0.726%,and had a similar variation trend with phytoplankton biomass.The vertical distribution profiles revealed that BSi contents were relatively stable,in accordance with the variations of the contemporary phytoplankton standing crop index.According to the stability analysis of BSi in sediments,BSi was not degradaded for the past two hundred years and remained in sediments steadily.Thus,BSi in sediments had the potential to invert paleoproductivity.To conduct further survey,the linear regression equation between BSi contents and phytoplankton biomass index could be used to calculate the phytoplankton productivity by BSi,so that paleoproductivity may be reconstructed during last 200 years. 相似文献
12.
Phytoplankton productivity and community structure in marginal seas have been altered significantly during the past three decades, but it is still a challenge to distinguish the forcing mechanisms between climate change and anthropogenic activities. High time-resolution biomarker records of two 210Pb-dated sediment cores(#34: 28.5°N, 122.272°E; CJ12-1269: 28.861 9°N, 122.515 3°E) from the Min-Zhe coastal mud area were compared to reveal changes of phytoplankton productivity and community structure over the past 100 years. Phytoplankton productivity started to increase gradually from the 1970 s and increased rapidly after the late 1990 s at Site #34; and it started to increase gradually from the middle 1960 s and increased rapidly after the late 1980 s at Site CJ12-1269. Productivity of Core CJ12-1269 was higher than that of Core #34. Phytoplankton community structure variations displayed opposite patterns in the two cores. The decreasing D/B(dinosterol/brassicasterol) ratio of Core #34 since the 1960 s revealed increased diatom contribution to total productivity. In contrast, the increasing D/B ratio of Core CJ12-1269 since the 1950 s indicated increased dinoflagellate contribution to total productivity. Both the productivity increase and the increased dinoflagellate contribution in Core CJ12-1269 since the 1950–1960s were mainly caused by anthropogenic activities, as the location was closer to the Changjiang River Estuary with higher nutrient concentration and decreasing Si/N ratios. However, increased diatom contribution in Core #34 is proposed to be caused by increased coastal upwelling, with higher nutrient concentration and higher Si/N ratios. 相似文献
13.
Biomass and primary productivity of picophytoplankton (PP; phytoplankton <3 μm) and larger phytoplankton (>3 μm) were determined during an annual cycle along the salinity gradient in North Carolina’s Neuse River Estuary (NRE), a eutrophic, microtidal estuary. The PP were a major component of total phytoplankton biomass and productivity, contributing ∼35–44% of the total chlorophyll a (Chl a) and 42–55% of the total primary productivity. Chl a and productivity of PP decreased from the upper to lower estuary, although the PP contribution relative to larger phytoplankton remained nearly constant. Significant PP growth occurred in the spring, but PP productivity and biomass were maximal in summer. PP productivity and biomass were positively correlated with temperature and dissolved inorganic phosphorus concentrations, which were maximal in summer due to release from sediments. Biomass and productivity of PP and >3 μm phytoplankton were also positively correlated, suggesting that growth conditions favoring the onset of blooms of larger phytoplankton species will similarly affect PP. High PP productivity and biomass in the NRE support the notion that PP play an important role in the production and eutrophication potentials of this estuary. High PP productivity and biomass have been noted in several other temperate estuaries, all sharing a common feature with the NRE—long residence time. These findings challenge the assumption that PP relative importance should be minimal in eutrophic systems. 相似文献
14.
Howard Freeland Ken Denman C.S. Wong Frank Whitney Renée Jacques 《Deep Sea Research Part I: Oceanographic Research Papers》1997,44(12):2117-2129
Sea-surface temperatures in the Northeast Pacific Ocean show a warming trend, and salinities show a declining trend, in data collected over the last 60 years. These changes combine to reduce the density of the surface layer over a large area of the Northeast Pacific. The declining surface density changes the energetic requirements for the formation of a surface mixed layer, and observations at Ocean Station Papa indicate that mid-winter mixed layer depths are showing a marked decline. The reduction in the depth of penetration of the winter-time mixed layer should reduce the nutrients entrained into the upper ocean each winter. Observations suggest that near surface nutrient levels are declining at Papa but remain well above levels that might inhibit productivity. However, at present the productivity of large phytoplankton appears to be limited by iron supply which is thought to be mainly from the atmosphere. A shallower mixed layer depth could increase the concentration of iron in this layer. The increase in iron would increase the utilization of nitrate, mainly by diatoms, and new production and the f ratio would increase. 相似文献
15.
淀山湖的浮游植物及其能量生产 总被引：19，自引：0，他引：19
浮游植物是水生生态系统中的初级生产者，系统地研究浮游植物的演变以及能量生产，对深入了解水生生态系统的结构和功能，保护和改善水质，都有理论和实际意义。因而引起国内外学者的普遍重视。关于湖泊浮游植物种类组成、密度、多样性指数、初级生产力及其与生态因素的关系的研究很多，但在淀山湖，尚缺乏这些方面，尤其是与环境变化的关系的系统研究。因此，作者在前人工作的基础上，较全面地报道了淀山湖浮游植物与水体环境变化的 相似文献
16.
Standing stock of phytoplankton and primary productivity in Penaeus orientalis larval multiplication releasing area of the Xiangshan Bay 总被引：1，自引：1，他引：0
INTRODUCTIONTheXiangshanBayisoneoftheimportantmarineaquaculturebasesinZhejiang.Since1982,themultiplicationreleasingexperimentsofPenaeusorzentalisKishinouyelarvalhavebeencarriedoutinthebay.Thestudyonthephytoplankton,chlaconcentrationandproductivityandthelifepatternofreleasedlarvaeprawnintheXiangshanBayisoneoftheimportanttasksoftheNationalKeyProject--AquaticExploitationTechniqueResearchinLakesandHarbors.TherearemanylargebaysandharborsalongChina'scoast,butonlyafewobservationshavebeend… 相似文献
17.
To clarify the beneficial roles of naturally occurring organic ligands on the growth of phytoplankton in newly upwelled water,
phytoplankton culture experiments using disphotic zone water were conducted to discriminate between the effects of EDTA in
the detoxification of certain toxic metal ions and increasing the availability of essential metals. Culture media were prepared
by adding EDTA and Chelex-100, separately or in combination, to disphotic zone water samples. Our proposed working hypothesis
is that phytoplankton growth can be enhanced by removing toxic metal ions from culture media by Chelex-100 and by detoxification
of toxic metal ions or increasing the availability of essential metals by EDTA. A shortening of the lag period and an increase
of the specific population growth rate were clearly observed after the addition of Chelex-100; nd EDTA. The effects of EDTA
were more considerable than those of Chelex-100; a 17 to 44% in shortening the lag period and a 35 to 56% increase in the
growth rate, when comparing the effects of Chelex-100 with those of EDTA. The similar effects of removing toxic metal ion
by Chelex-100 as those of detoxification by EDTA suggested that EDTA has a role not only of detoxification but also of increasing
the availability of essential metals. The present study suggests that the low productivity in newly upwelled water observed
by Barber and Ryther (1969) can be ascribed to both toxic metal ions and a lack of available forms of essential metals because
of their low contents of free natural organic ligands. 相似文献
18.
INTRODUCTIONComparedwithotheroceansintheworld ,thereisrelativelyhigherlevelofnutrients (ni trate ,phosphate ,silicate)intheSouthernOcean .Butprimaryproductivitiesarelow ,andnewproductionisalsoonlyinthemiddlelevelthere .Itiscommonlyconsideredthatthelowerpro ductivitiesintheSouthernOceaniscausedbylowtemperature ,lowlight,lowstabilityofwa ter,scarcityoftraceelementsuchasironandgrazingbyzooplankton (Burkilletal.,1 995) ,etc.ThemostexistedstudiesconcentratedontheAtlanticSectoroftheSouthernO… 相似文献