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中国对虾对日本刺沙蚕的摄食率研究 总被引：3，自引：0，他引：3
于１９９６年６月在山东莱阳市养殖场采集中国对虾（体长４．５－６．０ｃｍ体重１．２－３．７ｇ）和日本刺沙蚕（体长１．０－５．０ｃｍ）通过持续２０的室内实验，研究中国对虾对日本刺沙蚕的摄食率，实验条件为：水温２１－２３℃，海水盐度３０－３１，ｐＨ＝８．２－８．６，室内自然光照，实验结果表明，中国对虾对日本刺沙蚕的摄食率Ｃ（ｇ．ｇ＾－１．ｄ＾－１）与体重Ｗ（ｇ）的关系为Ｃ＝０．１５３Ｗ＾０．７０７２，在 相似文献
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珠江口红拟石首鱼的池养生长与饲养 总被引：1，自引：0，他引：1
对新引进的红拟石首鱼Ｓｃｉａｅｎｏｐｓ ｏｃｅｌｌａｔｕｓ进行咸水池养生长特性与饲养技术研究,结果表明,其生长旺盛期在２龄。应用ｖｏｎ Ｂｅｒｔａｌａｎｆｆｙ方程求得人工饲养条件下其体长、体重生长方程分别为Ｌ１＝６５６．２７２２〗１－ｅ＾－０．５９９８ｔ＋０．０８２３）【和Ｗｔ＝４１９３．９０２１〖１－ｅ＾－０．５９９８（ｔ＋０．０８２３）〗＾２．８８３４。体重生长拐点于１．７龄处。面积为６．５ｈ 相似文献
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湛江港污损生物挂板试验 总被引：11，自引：0，他引：11
１９９１年４月至１９９２年３月在湛江港内的试验浮筏上进行了污损生物周年挂板调查。共记录５９种生物。优势种是浒苔Ｅｎｔｅｒｍｏｒｐｈａ ｓｐ．和网纹藤壶Ｂａｌａｎｕｓ ｒｅｌｉｃｕｌａｔｕｓ。表层月板附着量变化幅度１０．０－２５０．０ｇ．ｍ＾－２，底层月板附着量变化幅度为３．０－５６８０．５ｇ．ｍ＾－２，年板全年附着量炒２２３４７．１ｇ．ｍ＾－２。 相似文献
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九孔鲍人工配合饵料的初步研究 总被引：3，自引：0，他引：3
在实验室条件下，对鲍人工的饵料保形率和腐败度进行了测试，测定结果该人工饵料在水温３０℃内，１２ｈ的保形率达８８％；在水温２１℃内７２ｈ的保形率仍达到８３％；水温２１℃以下人工饵料在水中浸泡１２ｈ后的水体溶氧为６．０８ｍｇ／ｄｍ＾３以上，化学耗氧量则不论水温高低，水体里都达到１１ｍｇ／ｄｍ＾３；水体ｐＨ值在水温１５￣２１℃间，１２ｈ后其值变化不大，而在水温２４￣３０℃间，其值由８．２下降至７．０。通 相似文献
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南海东北部沉积物间隙水氮和硅的研究 总被引：9，自引：0，他引：9
测定了南海东北部沉积物间隙水中ＮＯ３－Ｎ，ＮＯ２－Ｎ和ＳｉＯ３－Ｓｉ的含量。６个站位的５－１０ｃｍ层的ＮＯ３－Ｎ，ＮＯ２－Ｎ和ＳｉＯ３－Ｓｉ的含量分别为０．４７－１．７０，０．８４－２．６０和１０．１７－１１．６９μｍｏｌ／Ｌ。研究了上术物质含量在５０号站的深度分布。估算了ＮＯ３－Ｎ和ＳｉＯ３－Ｓｉ从间隙水向覆水扩散的通量分别为通量分别为０．０３３和０．０１９ｍ ｍｏｌ／ｍ＾２．ｄ。 相似文献
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根据１９９０年３－５月在大鹏湾盐田海域观测的资料分析结果，春季大鹏湾盐田海域叶绿素含量的日变化呈多峰曲线型，其测值范围为０．０８－５．１８ｍｇ／ｍ＾３，平均为１．２１ｍｇ／ｍ＾３，其中４月份叶绿素ａ含量变化较小，只有个别测值小于１．００ｍｇ／ｍ＾３，５月份波动相对较大，变动范围在０．０８－２．５１ｍｇ／ｍ＾３之间。 相似文献
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中国北方盐田和盐湖高盐水域藻类的初步研究 总被引：3，自引：0，他引：3
于１９８６年３月－１９９０年９月，对中国北方一些盐田和盐湖的高盐水域（盐度６１．０－３２０．０）中的藻类（主要是浮游藻）进行调查。在青岛东风盐场和天津汉沽盐场每月２次定点采集藻类标本水样７２份以及随机在山西解地、青海尕海，新疆达板城盐湖和巴里坤湖采集水样５份。鉴定出蓝藻５种，绿藻８种，硅藻８种。结果表明，均是典型的耐盐或喜盐种类，但其种的多样与水体的盐度呈负相关，藻类种群生物量以春季和秋季最为丰富 相似文献
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太湖水中可溶性有机质,悬浮质和浮游藻类色素的光学特性的测定 总被引：1，自引：0，他引：1
本文着重分析了分光光度计测定的太湖水体中悬浮质、可溶性有机质和浮游藻类色素在可见光波段(400nm—700nm)的吸收;讨论了对池塘及两种高等植物色素吸收的对比测定;并利用迭代回归方法对测试样品的散射效应进行了订正。结果表明:(1)可溶性有机质吸收在短波部分较强;并且随着入射波长的增大,吸收几乎呈指数律减小,减小速率比国外海洋中的测量结果小。(2)水中悬浮质对光具有较强的散射作用,散射系数约按入射波长呈倒数变化。(3)不同植物中的色素的吸收光谱有明显差异。此外,利用所测数据,本文还对冬季太湖水体的反射光谱和向下光照衰减系数进行了数值计算,表明该水体对入射光照的反射和衰减与纯净水情况有很大差别,目此,太湖水光学特性研究中必须考虑水中物质的影响。 相似文献
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R. H. S. McColl 《新西兰海洋与淡水研究杂志》2013,47(3):509-523
Abstract Chemical parameters (pH, Eh, carbon, Kjeldahl nitrogen, total phosphorus, 0.5M H2SO4‐extractable phosphorus, organic phosphorus, and water‐soluble phosphorus) were measured in the surface layers of sediments collected from various depths in Lakes Rotowhero, Okaro, Ngapouri, Rotokakahi, Okareka, Tikitapu, Okataina, and. Rotoma during October 1972. The sediments of the productive geothermal lake, Rotowhero, were markedly different from those of the cold‐water lakes: they had relatively low pH values, high carbon (mean 8.5%) and organic phosphorus (mean 4160 μg.g?1) concentrations, and very high total phosphorus concentrations (mean 4770 μg.g?1), probably as a result of enrichment by hot springs. The mean concentrations in the sediments of the cold‐water lakes were carbon 3.2–7.9%, Kjeldahl nitrogen 3380–8310 μg.g?1 and phosphorus 690–1780 μg.g?1. These concentrations are within the ranges for New Zealand terrestrial topsoils, but the lake sediments appear enriched in phosphorus relative to local topsoils. Total carbon, nitrogen, and phosphorus concentrations of sediments tended to be highest in the eutrophic lakes (Okaro, Ngapouri) although the deep oligotrophic lakes (Okataina, Rotoma) had relatively high total phosphorus concentrations (means 1400, 1510 μg.g?1). Overall, the carbon, nitrogen, and phosphorus concentrations of the sediments showed little relationship to the trophic state of the lake. Organic phosphorus concentrations of the surface layers of sediments were similar in all the cold‐water lakes (mean 319 μg.g?1). The proportion of the total phosphorus apparently ‘fixed’ in mineral material was minimal (0–1%) in sediments from the eutrophic and mesotrophic lakes, but in the oligotrophic lakes was similar to that in New Zealand topsoils (9–14%). Reducing conditions may cause solution of a high proportion of the ‘fixed’ phosphorus in the eutrophic lakes. The water‐soluble phosphorus concentrations in the sediments of the five shallow cold‐water lakes (Okaro, Ngapouri, Rotokakahi, Okareka, Tikitapu) correlated positively with trophic state and with concentrations of dissolved phosphorus in the lake waters. Carbon, nitrogen, and phosphorus concentrations in the sediments tended to vary with overlying water depth. This should be considered when comparisons are made between lakes. 相似文献
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R. H. S. McColl 《新西兰海洋与淡水研究杂志》2013,47(2):169-182
Chlorophyll production by Chlorella vulgaris Beij. var. vulgaris was used to estimate alga‐available phosphorus in clays, soils, and lake sediments suspended in water at concentrations appropriate to lake inflows during floods (100–500 g/m3). Chlorella apparently used 24–81% of 0.5M H2SO4 extractable phosphorus in clays from topsoils, about 25% from lake sediments, and 0.3–1.0% from, subsoils low in phosphorus and with high phosphorus retention. The presence of suspended soil material did not reduce the availability to Chlorella of inorganic phosphorus added to the cultures. Increasing the Chlorella population by adding inorganic phosphorus resulted in an apparent increase in availability of phosphorus from the soil, possibly as a result of enzymic mineralisation of organic soil phosphorus. The amount of available phosphorus in lake sediments was not a reliable guide to the trophic condition, of the lake. Suspended material from sediments, soils, and especially clay eroded from fertilised topsoils may provide phosphorus for algal growth in lakes. If allophanic clays are applied to lakes to sorb phosphorus and hence control eutrophication, the particles must settle out before planktonic algae in the photic zone can use the adsorbed phosphorus. 相似文献
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On the basis of the analysis of the many-year data on the vertical distributions of particulate organic carbon and nitrogen, we compute their annual average amounts for three typical layers of water in the deep part of the Black Sea: for a layer located above the oxycline and characterized by the formation of new portions of particulate organic matter in the course of photosynthesis, inside the oxycline, where the major part of oxygen is consumed and the major part of the flux of particulate organic matter is oxidized, and for the upper part of the anoxic zone characterized by the most active microbiological processes of oxidation of the organic substances and production of sulfides. The available literature data on sedimentation traps are used to study the downward annual average fluxes of particulate organic matter from the euphotic zone into the oxycline and into the anaerobic zone. The seasonal variability of the amounts and fluxes of particulate carbon and nitrogen is revealed. 相似文献
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Michiro Matsuyama 《Journal of Oceanography》1973,29(2):53-60
Vertical distribution of organic substances of settling matter and sediments was measured in a typically meromictic lake, Lake Suigetsu. Proteinous materials were rapidly eliminated in the early stage of settling in the lake water. No major difference was found in amino acid composition of the hydrolysates of all samples, indicating that there had occurred no selective decomposition of amino acids. In contrast, the decomposition of carbohydrates was sluggish. Water-extractable carbohydrates were abundant in the sediments. Dissolved carbohydrates and amino acids, formed in the sediments, were partly metabolized by photosynthetic sulfur bacteria,Chromatum sp. populated in the chemocline. 相似文献
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Roles of Biogeochemical Processes in the Oceanic Carbon Cycle Described with a Simple Coupled Physical-Biogeochemical Model 总被引：1，自引：0，他引：1
To evaluate the contribution of biogeochemical processes to the oceanic carbon cycle and to calculate the ratio of calcium
carbonate to organic carbon downward export, we have incorporated biological and alkalinity pumps in the yoked high-latitude
exchange/interior diffusion-advection (YOLDA) model. The biogeochemical processes are represented by four parameters. The
values of the parameters are tuned so that the model can reproduce the observed phosphate and alkalinity distributions in
each oceanic region. The sensitivity of the model to the biogeochemical parameters shows that biological production rates
in the euphotic zone and decomposition depths of particulate matters significantly influence horizontal and vertical distributions
of biogeochemical substances. The modeled vertical fluxes of particulate organic phosphorus and calcium carbonate are converted
to vertical carbon fluxes by the biological pump and the alkalinity pump, respectively. The downward carbon flux from the
surface layer to the deep layer in the entire region is estimated to be 3.36 PgC/yr, which consists of 2.93 PgC/yr from the
biological pump and 0.43 PgC/yr from the alkalinity pump, which is consistent with previous studies. The modeled rain ratio
is higher with depth and higher in the Pacific and Indian Oceans than in the Atlantic Ocean. The global rain ratio at the
surface layer is calculated to be 0.14 to 0.15. This value lies between the lower and higher ends of the previous estimates,
which range widely from 0.05 to 0.25. This study indicates that the rain ratio is unlikely to be higher than 0.15, at least
in the surface waters. 相似文献
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Annual Variation of Benthic Nutrient Fluxes in Shallow Coastal Waters (Gulf of Trieste, Northern Adriatic Sea) 总被引：5，自引：0，他引：5
Abstract. Benthic fluxes of dissolved N. Si and P nutrients, alkalinity, dissolved inorganic C (DIC), and O2 from sediments in the Gulf of Trieste (northern Adriatic, Italy) were measured monthly for 16 months, using laboratory incubated flux chambers at in siru temperatures in the dark. The annual average fluxes were: 02 = -19.3 ± 8.2, DIC = 13.7 ± 9.6, NO3 = -0.04 ± 0.16, NH4 = 0.3 ± 0.4. PO4= 4.001 ± 0.01, Si = 0.9 ± 0.1 mmol m-2 d-1, with strong temporal fluctuations. The highest effluxes of all nutrients and DIC were observed in the summer. Small effluxes of DIC and NH4 and influxes of Si and PO4 were observed in late winter. Only NH4 (ca. 50%) and Si (ca. 70%) fluxes were significantly correlated with temperature. This correlation suggests that the rate of downward input and the quality of sedimented organic matter (autochthonous and allochthonous) were superimposed on the temperature fluctuations. High DIC, NH4 and Si effluxes observed in May 1993 during low temperature were due to the degradation of sedimentary organic matter produced by an early spring bloom of benthic microalgae which occurred about 6 weeks earlies while the autumn phytoplankton bloom was simultaneously reflected in enhanced benthic fluxes due to higher temperature. The role of benthic biological advection in this transport across the sediment-water interface, evaluated by comparison between measured benthic and calculated diffusive fluxes from nutrient pore water concentrations, was of minor importance. This is probably due to low infaunal activity throughout the year it was localized mostly in the narrow surficial layer. The annual average diffusive fluxes of NH4 and PO4 were higher than those measured, probably due to the presence of nitrificationdenitrifi-cation processes and redox-dependent chemical reactions at the oxic sediment-water interface, respectively. Only during bottom-water hypoxia in September 1993 did strong PO4 effluxes prevail. Calculations based on the Redfield stoichiometry of oxic decomposition of organic N to NH4 and NO3, and differences between diffusive and measured NH4 fluxes showed that denitrifkation averaged 0.8 mmol m-2 d-1. Significant correlations between NH4 and PO4 DIC and Si, and NH4 and Si fluxes suggested their parallel regeneration and utilization at the sediment-water interface. The nutrient fluxes observed were not significantly linked to O2 consumption, suggesting also that anaerobic oxidation processes were important at the sediment-water interface in the gulf. The N, P and Si nutriqnts released from sediment pore waters are probably utilized in benthic microalgal and bottorn-hater primary production. This indicates that pelagic and benthic communities in the central part of the Gulf of Trieste function relatively independently of each other. 相似文献