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31.
大亚湾微表层和次表层海水营养盐的研究 总被引:11,自引:0,他引:11
根据1998年秋季(10、11月)、1999年春、秋季(4、5、10月)5个航次对大亚湾海区微、次表层的调查结果,分析了微表层海水对氮、磷、硅营养盐的富集概况,讨论了营养盐与环境因子的关系。结果表明:大亚湾海区微表层海水对氮、磷、硅营养盐均有富集作用,因海况及季节不同,富集因数(EF)与其他海区的有所差别;无论夏季或秋季,大亚湾海区微表层海水中无机氮都以NH4-N为主要存在形态;其余水层则以NO3-N为主要存在形态。结果还表明,微表层、次表层海水中NH4-N与BOD5、COD测值都呈高度显著正相关,与PO4-P和SiO3-Si含量均无相关,说明大亚湾海区水中含氮有机物较含磷有机物丰富。 相似文献
32.
33.
rmIoxThe averag annual dischaIge of the Zhujiang Xiver is 3. 32 x l0ll m3, which ranks theZhujiang River just end to the Changjiang River in China. The dischnye occutring duringthe fltal m between APril and ffepteTnber accounts for 80% of the yearly total. The Zhu-jiang hiver has a yeaIy sediment load of about 1 x l08 tons, which also concentrates in theM arn (Zhao, l990; Chen et al., 1998). The Zhujiang Xiver delta,which has l2 cities ofdifferent sizes and more than 40 towns with a po… 相似文献
34.
高效液相色谱法测量海洋浮游植物色素浓度 总被引:2,自引:1,他引:2
JGOFS计算和SeaWiFS计划推荐高效液相色谱(HPLC)作为海洋浮游植物色色浓度的测量方法。文章参考SeaWiFS计划制定的HPLC分析规范,叙述采用反相C18ODS色谱柱、996PDA、自动进样器(未配柱温箱)和三元梯度的色谱法测量海洋浮游植物色素浓度的具体实践。 相似文献
35.
Anna Badosa Dani Boix Sandra Brucet Rocío Lpez-Flores Xavier D. Quintana 《Estuarine, Coastal and Shelf Science》2006,66(3-4):513-522
The role of the hydrological regime in the nutrients and zooplankton composition and dynamics has been analysed in five lagoons of La Pletera salt marshes (NE Iberian Peninsula) during a complete hydrological cycle (2002–2003). Two of the lagoons have their origin in the old river mouths while the other three were recently created in the framework of a Life Restoration project. This fact has also allowed us to study the effect of the lagoon age on nutrient and zooplankton composition and dynamics. The salt marsh hydrology is determined by a prolonged period of confinement without water inputs, irregularly interrupted by sudden water inputs due to flooding events (sea storms or intense rainfalls). While the dynamics of oxidized nitrogen compounds in the lagoons depends on the water inputs variability within each hydrological cycle, the internal load of phosphorus, total nitrogen and organic matter is related more to the cumulative mechanisms during the confinement periods. Accumulation processes may be easily related to lagoon age, since old lagoons have higher content of nutrients and organic matter, suggesting that these lagoons progressively accumulate nutrients during the successive confinement events. This is the usual case for most Mediterranean salt marshes without an artificially manipulated water regime. The zooplankton community in La Pletera integrates the effects of both the hydrological regime and the lagoon age since the former determines the temporal pattern of the main zooplankton species and the latter explains differences in composition and structure between old and new lagoons. 相似文献
36.
The data of SeaWiFS (Sea-Viewing Wide Field-of-View Sensor), installed on SeaStar, has been used to generate SSC (suspended sediment concentration) of complex and turbid coastal waters in China. In view of the problems of the SeaDAS (SeaWiFS Data Analysis System) algorithm applied to China coastal waters, a new atmospheric correction algorithm is discussed, developed, and used for the SSC of East China coastal waters. The advantages of the new algorithm are described through the comparison of the restdts from different algorithms. 相似文献
37.
九龙江流域水葫芦打捞去除水体营养盐模型研究 总被引:1,自引:0,他引:1
水葫芦被收获时,水体中的营养盐也将包含在植物组织中而被去除.本研究首先通过野外实验和参考国内外有关文献,建立了九龙江流域水葫芦生长数学模型和持续生产模型,确定了模型的各有关参数:水葫芦生长容量K值为25.6 kg/m2、最大生长速率rmax为0.12d-1;水体中氮和磷的半饱和系数hN和hP值分别为0.2和0.03;水葫芦最低生长温度(mθin)为7℃,最适水温(oθpt)为30℃,最高生长温度(θmax)为40℃.随后采用所建立的模型计算了研究区水葫芦打捞的营养盐去除效果,研究区面积6 000m2的水体实施水葫芦打捞策略后,1a所能收获的水葫芦最大产量为9.18×105kg,去除的TP为214.4kg,TN为966.6kg. 相似文献
38.
Zhang Jinshan Yu Guohua
Research Engineer River Harbour Department Nanjing Hydraulic Research Institute Nanjing Research Senior Engineer River Harbour Department Nanjing Hydraulic Research Institute Nanjing 《中国海洋工程》1995,(3)
- Based on field investigations, this paper analyzes three types of harbour basinns and navigation channel excavated on seabed in Jiaozhou Bay, get a general rule of deposition for excavated trough, it found that pollution is one of crucial factors resulting in the deposition of the excavated trough in the east shore of Jiaozhou Bay. With these results, it predicted the annual deposition thickness for the excavated trough and disclosed the fact that it can't be deposited deadly during one storm. At the same time, with two-dimensional numerical model, it studied the effects of the excavated trough and the reclamation near shore on tidal cureent and said that the excavated trough can decrease the current velocity passing through the trough about 10- 15%, but only limited inside and near the trough and there are no effect on other regions; reclamation can cut off the pollution sources and no obvious effect on the currents of the Jiaozhou Bay. Connecting the deep trough and Cangkou tidal channel with a new 相似文献
39.
利用在本系列研究第一部分中所建立的耦合的生物物理模型,模拟了渤海浮游植物生物量和营养盐含量的年度循环特征.模拟结果显示:藻类的春季水华是由经过一冬积累在水体中的营养盐导致,而水华开始的时间在浅水区明显早于深水区,对此深水区水体层化结构的形成可能起着重要作用;另一方面,河载营养盐与悬起的沉积物所释放的营养盐是诱发夏季水华的共同原因.基于模型结果,我们还发现:渤海的浮游植物动力特性就整体而言依然受无机氮限制,但是在莱州湾,磷限制特性表现得非常明显,这主要是由于每年黄河都要携带大量的无机氮进入海水,从而导致莱州湾营养盐的氮磷比已远远超过16. 相似文献
40.
A comprehensive numerical study on the three-dimensional structure of a turbulent jet in crossflow is performed. The jet-to-crossflow velocity ratio (R) varies in the range of 2 - 16; both vertical jets and inclined jets without excess streamwise momentum are considered. The numerical results of the Standard two-equation k-ε model show that the turbulent structure can be broadly categorised according to the jet-to-crossflow velocity ratio. For strong to moderate jet discharges, i.e. R> 4, the jet is characterized by a longitudinal transition through a bent-over phase during which the jet becomes almost parallel with the main freestream, to a sectional vortex-pair flow with double concentration maxima; the computed flow details and scalar mixing characteristics can be described by self-similar relations beyond a dimensionless distance of around 20-60. The similarity coefficients are only weakly dependent on R. The cross-section scalar field is kidney-shaped and bifurcated, vvith distinct double concentr 相似文献