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1.
辽河口湿地碳、氮、磷空间分布及季节动态特征 总被引：2，自引：0，他引：2
以2008年10月和2009年5月2次对辽河口湿地野外调查获取的数据为基础,研究了辽河口湿地生源要素碳、氮和磷的时空分布特征、湿地植被对营养元素的累积及对土壤营养元素氮、磷分布的影响.结果表明:辽河口湿地表层土壤有机碳5月和10月含量分别在0.62～13.17 mg/g和11.06～40.74 mg/g之间,10月盐化草甸土和滨海沼泽盐土有机碳含量较高,5月4种类型土壤有机碳含量无明显差异;全氮5月和10月含量分别在0.80～3.43 mg/g和0.77～2.90mg/g之间,盐化草甸土和滨海沼泽盐土表层土壤氮含量相对较高,滨海潮滩盐土最低;无机氮(NH4+-N和NO3--N)含量较低,且以铵态氮为主,5月略高于10月含量;全磷含量均在0.36～0.66 mg/g之间,无显著季节差异.碳、氮和磷的垂直剖面分布特征表明,土壤表层有机碳、全氮、无机氮和全磷含量明显高于各底层,以芦苇为主要植被的盐化草甸土各剖面的营养元素含量高于以翅碱蓬为主的滨海潮滩盐土含量.5月芦苇对氮磷的积累量高于10月,且氮磷含量在芦苇地上器官的分布趋势为叶>茎>穗.植被的生长对湿地土壤中生源要素碳、氮和磷含量的季节变化有重要影响,其对营养元素氮、磷的累积降低了表层土壤中氮、磷的储量. 相似文献
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南极周边海域沉积物中的有机碳和氮元素地球化学特征对于深入研究全球碳循环和海洋生态环境演变具有重要意义。本文对取自南极罗斯海的RBA08C柱状样沉积物进行了有机碳和氮元素地球化学特征分析。结果表明:RBA08C柱样中TOC含量在顶部0～12cm呈现随柱深增加而降低的趋势,自12cm以深含量总体相对稳定;TN总体具有与TOC相同的变化趋势,两者含量变化呈现较强正相关性,说明可能具有相同来源;沉积物TOC/TN比值和δ13 C值揭示RBA08C柱样有机质主要为海洋生源沉积,其含量变化应主要受控于上层水体生产力、沉积速率和氧化还原环境等因素的共同作用;RBA08C柱样的TOC埋藏率约为50%,与位于普里兹湾埃默里冰架边缘的IS-4站柱样相同,加之较为相近的TOC和TN含量及变化趋势,表明两者可能具有相近的沉积速率,其所在的海区是南极海域较重要的碳循环和碳储区。 相似文献
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全球范围内有植被定植的海岸带栖息地(红树林、盐沼和海草床)是巨大的沉积物有机碳碳库，同时也是自然生态系统中最密集的碳汇之一，在全球碳循环中发挥着重要作用。针对江苏盐城海岸盐沼湿地沉积物有机碳的研究，区域上的稀疏性和偏向性限制了其作为区域碳汇能力的可靠估计。本研究采用47个100 cm深沉积柱样的现场调查数据，探讨了江苏盐城海岸盐沼湿地沉积物有机碳含量、密度和储量特征。结果表明，0～100 cm深度沉积物有机碳平均含量和平均密度分别为1.68%和23.07 kg/m3，不同盐沼群落沉积物有机碳含量和密度存在一定的差异，其中有机碳平均含量大小排序依次为互花米草>芦苇>盐地碱蓬，有机碳密度排序为芦苇>互花米草>盐地碱蓬。总体而言，3种盐沼群落沉积物有机碳含量的垂向变化趋势与有机碳密度变化趋势具有一致性，芦苇和互花米草表聚性明显。沉积物有机碳含量与其理化性质有关，互花米草群落沉积物有机碳含量具有明显的粒度控制效应，而其他群落不显著。3种盐沼湿地类型0～100 cm深度沉积物总碳储量约为6195.27×103Mg C。研究成果揭... 相似文献
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《海洋湖沼通报》2020,(4)
为了研究明湖湿地公园湖区内表层底泥中氮、磷营养盐和有机碳污染水平及分布现状,对明湖湿地5个区域26个采样点的表层(0～10 cm)底泥中总氮(TN)、总磷(TP)和总有机质(TOM)进行了测定、分析,结果表明:表层底泥TN含量介于285～4500 mg/kg间,均值为1779.6 mg/kg,分布趋势为西南(MS)区东南(ME)区东北湖响水河口(HK)湖中心(MC)区西北(MN)区;TOM含量介于17.13～189.30 g/kg间,均值为55.99 g/kg,空间分布与TN相似的格局;TP含量介于261～709 mg/kg间,均值为639 mg/kg,分布与TN、TOM有差异,最大值出现在HK区。TN与TOM二者间呈极显著正相关(r=0.951~*,p0.01),TP与TOM之间关联性不明显(r=0.627)。结合有机指数(OI)和综合污染指数(FF)评价结果知,研究区内表层底泥营养盐已达中度污染水平,其中TN超标率较高,是明湖湿地表层底泥富营养化的主控因子。且湿地南部底泥中氮、磷营养盐及有机质污染属严重级别,污染程度超过最低生态毒性效应级别,存在较高的生态风险。 相似文献
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造纸废水灌溉对芦苇湿地微生物的影响研究 总被引：2，自引：0，他引：2
为了解造纸废水灌溉对滨海芦苇湿地的影响,测定了几种灌溉条件下湿地基质中微生物数量、微生物量碳/总有机碳(MBC/ TOC)和土壤有效硫等指标.结果表明:造纸废水灌溉能显著提高基质中微生物数量和活性,且受季节影响较明显,一般在9月份最高;微生物数量在基质内垂直分布为上层>下层,特别是放线菌、真菌;反硝化细菌与土壤TN,纤维素分解菌与废水COD去除率,及MBC/TOC与基质呼吸强度相关性较好;硫酸盐还原细菌数量在10月份以后激增,使基质变黑,但对芦苇根系影响较小.废水灌溉能改良滨海盐碱土壤,促进退化生态系统的修复,但不同灌溉模式对微生物种群组成的影响不同,推荐采用间歇灌溉(w4)或低水深恒流灌溉(w1)模式. 相似文献
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为研究防潮堤坝对滨海湿地植物及土壤性质的影响,本研究在昌邑国家级海洋生态特别保护区内,通过样线法进行野外调查采样,进行防潮堤坝内外土壤、植被以及两者之间联系的分析,研究了堤坝内外植被及土壤性质差异。结果表明:堤坝内外土壤、植被有一定的差异;堤坝外部土壤C、N、P含量小于堤坝内部,堤坝外部土壤盐度大于堤坝内部;堤坝外部是以盐地碱蓬(Suaeda salsa)和獐毛(Aeluropus sinensis)为主滨海湿地景观,堤坝内部则是以柽柳(Tamarix chinensis)为主的灌草丛景观;保护区内物种丰富度与土壤盐度值呈负相关关系,随着盐度的升高,堤坝外部物种丰富度低于堤坝内部;芦苇(Phragmites australis)体内TC、TN、TP及C︰N︰P与土壤C、N、P含量及C︰N︰P没有明显相关性,而柽柳体内N含量与土壤P含量呈明显负相关关系,说明木本植物比草本植物更加依赖土壤中营养元素的供给。 相似文献
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潮滩作为重要的湿地类型和高效的有机碳汇备受关注,近期围垦、养殖等人类活动和互花米草入侵对潮滩生化环境和有机碳埋藏产生了重要影响。本研究选取了福建三沙湾三处不同植被类型的潮滩各取得沉积物短柱样,测定沉积物的总有机碳含量(TOC)、稳定碳同位素(δ13C),结合210Pbex测试计算的沉积速率,估算了不同区域的有机碳埋藏通量(BC)。结果表明,互花米草阶段和红树林阶段TOC含量分别为0.67%和0.95%,比对应的光滩阶段分别提高了13.6%和26.7%,表明红树林对潮滩固碳效率的提升比互花米草更加显著。在两者的共同生长区域,随时间推移TOC含量显著下降,表明互花米草入侵挤占红树林生长空间之后,降低了潮滩的固碳效率。短柱样沉积物δ13C值分布范围在-24.70~-21.87‰,主要体现海源有机质同位素特征,但也会受潮滩植被生长类型影响。对各短柱样有机碳埋藏通量进行估算,得到研究区红树林生长阶段BC平均值为149.53 g/m2/yr,远高于互花米草生长阶段的平均值57.37 g/m2/yr。 相似文献
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山东南部近海沉积物中碳、氮、磷的分布特征 总被引：4，自引：0，他引：4
对山东近海31个站位表层沉积物中的总氮、总磷和总有机碳的含量和分布特征进行了研究。结果表明,总氮、总磷和总有机碳含量均较低,高值区主要分布在胶州湾及湾口和北部海域,总氮浓度范围为0.31～0.75mg/g,平均值为0.52mg/g,总磷浓度范围为0.18～0.32mg/g,平均值为0.24mg/g,总有机碳浓度范围为0.17%～0.49%,平均值为0.33%。相关性分析表明,总氮和总有机碳的相关性较好,总有机碳和总氮比值(TOC/TN)略高于Redfield比值,表明这两种生源要素的来源可能是一致的。 相似文献
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人工参礁在中国刺参(Apostichopus japonicus (Selenka))养殖业中被广泛应用,本文调查了2008年春、秋季刺参池塘中一种塑料人工礁表面的生物群落结构.采用沉积物捕捉器的方法调查了刺参池塘人工礁表面碳、氮、磷的循环及参礁的生态特征.结果表明,春季礁体底栖动物生物量及生物多样性高于秋季,底栖动物均集中在礁体外表面的缝隙内,4月礁体表面颗粒物,底泥沉积物总有机碳(TOC)平均含量分别为41.9 mg/g 和2.45 mg/g;总氮(TN)平均含量分别为4.1 mg/g 和0.2 mg/g.10月礁体表面颗粒物,底泥沉积物 TOC 含量分别为27.5 mg/g 和3.1 mg/g; TN 平均含量分别3.1 mg/g 和0.3 mg/g.4月 TOC, TN 沉积量分别达到711.2 mg/(m2·d)和70.7 mg/(m2·d);10月 TOC, TN 沉积量分别为804.9 mg/(m2·d)和87.3 mg/(m2·d).4月人工礁表面叶绿素/脱镁叶绿素(Chl a/Pheophytin)>1,表明礁体活体藻类较多.10月人工礁表面 Chl a/Pheophytin<1表明礁体表面降解颗粒物质较多.人工礁为刺参提供遮蔽场所,其表面生物膜为刺参提供优质食物,同时可增加池塘底面积,增强养殖系统稳定性. 相似文献
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鸭绿江河口西岸潮滩沉积物有机质对流域变化的响应 总被引：1，自引：1，他引：0
河流颗粒有机质提供了陆地碳循环的重要信息以及人类活动的记录,通过河口地区沉积物有机质组成,可反映流域变化及海陆间相互作用。2010-2011年分两次于鸭绿江河口西岸潮滩采集柱样4根及表层样23个。对样品进行有机质碳氮总量(TOC、TN)、碳氮同位素(δ13C、δ15 N)及沉积物粒度测试。分析结果表明,由河口向西,有机质受改造程度加深且来源逐渐复杂化,致TOC/TN与δ13C的相关性逐渐降低,δ15 N与沉积物粒度的相关性也随之降低。文中以δ13C为主线探讨沉积物有机质的来源及运移,TOC/TN作为辅助,δ15 N则用于指示生化条件的改变。柱样的δ13 C分布与河流入海输沙密切相关,水库对入海泥沙的拦截,致河口潮滩沉积速率减缓,从而增加了沉积物中海源有机质的含量,δ13C随之增加。潮滩西侧柱样的δ15 N增加指示了生活工业污水的大量排放。此外,表层样δ13C分布的方向性,指示了西水道门口处的快速堆积及潮下带物质的向岸运移,并在西岸潮滩向岸一侧富集。 相似文献
11.
Petrishchevsky A. M. Izosov L. A. Emelyanova T. A. Vasileva M. A. Lee N. S. 《Oceanology》2021,61(1):104-118
Oceanology - The geological-structural, magmatic, seismic, and thermometric models of the Earth’s crust and upper mantle of the Sea of Japan region are considered in relation to... 相似文献
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The elements Al, Cd, Co, Cu, Ni and Zn were concentrated from seawater using tetraethylenepentamine resin and analysed by atomic absorption spectrophotometry. The spatial distribution of these elements in the northwest Atlantic Ocean is discussed with respect to possible riverine inputs to the area from Puerto Rico. 相似文献
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This paper discusses remote sensing (RS) of the major types of water bodies by means of microwave radiometry. The analysis is based on theoretical models and experimental data taken under laboratory conditions, in a pool, from a shore, and over the oceans using aircraft and satellites. The radiation is found to depend on wind speed and the geometry of ripples, gravity waves, swell, foam, and some physical and chemical parameters of water such as its temperature, salinity, and concentration of some types of polutants. The estimates of the effectiveness of the microwave radiometric method for determining the above mentioned water-surface parameters are given. Examples of the application of microwave radiometry to obtaining operational information about some of them are also presented. The types of water observed are the inland waters, fresh or with a high concentration of salts, clean or polluted, and the oceans. The paper is based on the theoretical and experimental investigations conducted by the author and his colleagues at the Institute of Radio Engineering and Electronics of the Academy of Sciences in the USSR over the last 20 years. It also draws upon well-known Soviet and foreign publications. 相似文献
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J. David Smith Lorraine Plues Mireille Heyraud Robin D. Cherry 《Marine environmental research》1984,13(1):55-68
Ag, Al, Ca, Cd, Cu, Fe, Mg, Mn, Pb and Zn concentrations and 210Po and 210Pb activities were measured in 26 specimens of the squid Nototodarus gouldi taken from the waters of Bass Strait in one jigging operation. All the elements show wide ranges in concentrations in specimens apparently subject to the same environmental conditions. Copper concentration was 27-1 200 μg/g, and 210Po activity 4·8–24·2 Bq/g. The animal wet weights, the elements Ag, Al, Cd, Fe and Zn, and the radionuclide 210Po have coefficients of variation in the range 40–60%; Ca, Mg and Mn show the smallest variability (CV = < 30%), and Cu the greatest (CV = 12%). Significant correlations (p < 0·001) were found between the following pairs of elements: Cd-Zn, Cd-Cu, Zn-Cu, Mg-Mn, Fe-Mn, Ca-Mg and Fe-210Po. 相似文献
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20 0 0年 10月～ 2 0 0 1年 12月 ,对青岛太平角养殖海区的贻贝寄生中华豆蟹的感染情况进行了调查。以肥满指数为指标 ,通过对感染和未感染贻贝的比较 ,分析了中华豆蟹对贻贝的危害程度。结果表明 ,中华豆蟹对贻贝的感染率为 2 .0 %～ 2 0 .4 %。2 0 0 0年 11月和 2 0 0 1年 11月出现 2次感染高峰 ,分别为 9.7%和 2 0 .4 % ;最低感染率出现于 2 0 0 1年 1月和 3月 (均为 2 .0 % )。感染强度为 1～ 5 ,多数为 1(占感染个体的 83.2 % )。贻贝所感染的豆蟹的性别及感染强度与宿主的大小有关。小个体贻贝仅见雄豆蟹感染 ,绝大多数雌豆蟹见于壳长大于 2 cm的贻贝。未发现同一宿主体内同时感染 2只或以上的雌豆蟹。在调查的 15个月中 ,有 11个月被感染贻贝的肥满度显著低于未感染的贻贝 ,且雌豆蟹对宿主肥满度的影响大于雄豆蟹 相似文献
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Soil-sized particulates have been collected on board ship by a mesh technique from the lower troposphere of the North, Equatorial and South Atlantic Ocean, northern and southern Indian Ocean, South and East China Sea and various coastal localities.Spectrographic analysis reveals that, on average, the particulates have concentrations of Mn, Ni, Co, Ga, Cr, V, Ba, and Sr which are of the same order of magnitude as those in average crustal material. In contrast, the average concentrations of Pb, Sn, and Zn are one order of magnitude higher than those in average crustal material.Within this “world-wide” average there are significant geographical variations in the distributions of Pb, Sn, and Zn which may be related to anthropogenic sources.On the basis of trace-element distributions lower tropospheric soil-sized marine particulates have been divided into four genetic components; local, zonal, inter-zonal, and global. The proportions of these components vary geographically, and each component may have both a natural and an anthropogenic fraction. 相似文献
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The Mediterranean margin of Libya can be divided into three physiographic provinces, the Pelagian Shelf, the Sirt Embayment, and Offshore Cyrenaica. The petroleum potential of the Pelagian Shelf has been investigated but the Sirt Embayment and Offshore Cyrenaica are almost unexplored. During 2004–2005, new 2D pre-stack time-migrated seismic data were acquired and used to examine the large-scale structural, depositional, and salt tectonic features of the Libyan shelf and slope. The data cover approximately 38,000 line kilometers in water depths ranging from under 50 to over 3000 m.Cenozoic strata along much of the Libyan margin have a demonstrable progradational character punctuated by surfaces of erosion and margin failure. Within the Sirt Embayment the most visible retrogradational surface becomes seismically coincident with the top of Messinian unconformity. This retrogradational surface extends for over 700 km along strike and cuts both sides of the Sirt Embayment. Over 5000 cubic kilometers of material are missing from above this surface. There are two ideas for how retrogradation occurred. One idea relates the retrogradation to margin erosion during the Messinian salinity crisis. The other idea suggests that a large part of the Libyan margin experienced a cataclysmic failure during the late Miocene.Some existing models for offshore Libya have interpreted a widespread layer of halite lying within the Messinian which thickens basinward. This interpretation was probably based on the fact seismic reflection continuity was lost over much of the Sirt Embayment on older data beneath the top Messinian unconformity. The loss of good reflection character adversely affected exploration efforts by obscuring deep structures. Recent seismic data and a current understanding of salt behavior do not support the interpretation of thick halite within the Messinian section. Regional observations do not indicate any mobile halite present in the Sirt Embayment. There is a relatively thin, high amplitude and high velocity layer of non-halite evaporites (mainly anhydrite) which caps the Messinian section. Where this high amplitude and high velocity layer is absent or eroded, seismic continuity within the Messinian interval is restored. Limited available well data support this interpretation.True mobile halite is interpreted to exist in offshore Libya only in the far west of the Pelagian Shelf near the Tunisian border. Beneath the Pelagian Shelf are a series of tight contractional folds that are interpreted to be salt cored. Basins adjacent to the folds display geometries characteristic of salt withdrawal. The fold crests formed bathymetric highs which served as nucleation sites for nummulitic shoal development. These shoals are the principal reservoirs of the Pelagian Shelf. 相似文献