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101.
基于GF-1卫星数据对2013年11月22日青岛黄潍输油管道爆炸造成的海面溢油进行定量监测。研究首先采用2013年11月26日GF-1卫星数据对海面溢油进行提取,其统计面积为0.67 km2;其次,结合肖剑伟提出的油膜厚度单波段反演模型估算油膜厚度,最终计算得到溢油量为0.28 t;最后,对Band 1反射率与油膜厚度结果进行灰度分割,将溢油污染程度分为6级,对比发现两者分级结果较为一致。由此得出,通过反射率直接进行灰度分割可以对溢油污染进行有效的等级评定。 相似文献
102.
测定了2株球形棕囊藻Phaeocystis globosa P1、P2的psbA基因序列。发现得到的2个序列完全相同。以P2序列对比分析了P.globosa和P.antarctica的psbA基因在DNA序列、氮基酸序列和RNA二级结构上的差异性,发现2种棕囊藻psbA基因DNA序列和氨基酸序列非常保守,无插入/缺失,其核苷酸和氨基酸变异率分别为1.88%和1.13%。与核基因核苷酸的碱基替换不同,psbA基因核苷酸的碱基替换主要发生在密码子的第1位上。且不引起氨基酸的变化,引起氨基酸变化的碱基替换都发生在密码子的第2位和第3位上。在RNA二级结构上两序列的1~4茎环结构完全相同,表现出明显的棕囊藻属的特异性,其它结构区域差异较大。种间差异表现明显。由于psbA基因DNA序列和氨基酸序列非常保守,可能不适宜棕囊藻属的系统发育分析。但其RNA二级结构可能对于棕囊藻的分子分类有一定的参考价值。 相似文献
103.
Diel patterns in the chlorophyll a specific absorption coefficient of surface picoplankton, a*pico (γ) (m2·[mg chlorophyll a]−1), were studied at 7 stations under daily cycle of in situ light condition in the western subarctic Pacific and Japan Sea. All the data were normalized by dividing the anomaly with daily averaged a*pico (γ). Opposite diel patterns were observed for the normalized a*pico (443) and a*pico (675) with maximum toward dawn or dusk and minimum toward midday at 4 stations under low-irradiance (LI) conditions and vice versa at 3 stations under high-irradiance (HI) conditions. The absorption efficiency factors at red absorption peak, Q
a (675), were determined by reconstruction with intracellular chlorophyll a concentration and cell diameter. The normalized Q
a (675) also showed diel pattern with maximum toward midday and minimum toward dawn or dusk under LI. The diel pattern in a*pico (675) and Q
a (675) were primarily caused by changes in intracellular chlorophyll a concentration due to photoadaptation under LI. The diel pattern in a*pico (443) was influenced by pigmentation, as recognized by blue to red ratio [a*pico (443)/a*pico (675)] under HI. This study proposed that the opposite diel pattern in a*pico (γ) might occur for a wide range of algal species. The results presented here have important consequences for the interpretation of diel variations in optical properties observed in the open ocean. 相似文献
104.
It has for many years been controversial whether there was a Pleistocene high sea level on the Shandong Peninsula. Our investigations in recent years suggest that the red sandy sediments distributed around the Yuanyaodun village, Weihai County, the "Liukuang Red Bed" and the loess-like deposits near Penglai County should be terrestrial deposits, and there is will not a convincing evidence to confirm that abrasion landforms found above the 10m elevation oa the coast are of marine origin. From these, it is still not safe to say that a high sea level had occurred in the Shandong Peninsula during the Pleistocene. 相似文献
105.
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107.
研究了2003年10月采于珠江口5个站位的沉积物剖面酸挥发性硫化物(AVS)和同时提取的重金属(SEM:Pb,Zn,Cu,Cd,Ni)。其中,站位1、2位于中滩,其沉积物的AVS含量变化范围较小,为0.25—4.06μmol.g-1;站位3、4位于西滩,其沉积物的AVS含量变化范围较大,为0—26.09μmol.g-1。中滩和西滩沉积物的AVS含量均随深度增加。西滩表层沉积物的AVS含量接近于零,这可能与该水域较强的底层流和沉积物的再悬浮作用有关。站位5位于珠江口外侧,其表层沉积物的AVS含量相对较高,且垂向变化较小,可能是还原性沉积物间歇性再悬浮后重新沉积的结果。站位1、2和5沉积物中同时提取的重金属含量大体在0.95±0.2μmol.g-1范围内,随深度增加略呈下降趋势;而西滩沉积物重金属含量相对较高,为1.43—2.42μmol.g-1,且在一定深度范围内随深度增加呈明显下降的趋势,表明珠江口西滩沉积物中的重金属污染有加重的趋势。对AVS/SEM摩尔比值和单个金属的毒性效应研究显示,珠江口内尤其是西滩的表层沉积物存在重金属污染,对其中生活的底栖生物具有潜在的毒性效应。 相似文献
108.
不同浓度的营养盐(NO3-N,PO4-P)条件下Pb(Ⅱ)对2种海洋赤潮藻生长影响的研究 总被引:6,自引:2,他引:6
探讨海区环境容量的估算,为海水水质标准的制订提供理论依据,采用1次培养实验方法,研究了3种不同浓度的营养盐(NO3-N,PO4-P)条件下Pb(Ⅱ)对旋链角毛藻(Chaetoceroscurvisetus)、中肋骨条藻(Skeletonemacostatum(Greville)Cleve)的生长影响.采用抑制率-重金属离子浓度的对数方程拟合求算出3种浓度营养盐(NO3-N、PO4-P)条件下Pb(Ⅱ)对2种赤潮藻的96hEC50值,分别为8373,2563,2307;18523,10445,3494μg·dm-3,并根据方程应用origin7.0拟合3种不同浓度的营养盐(NO3-N,PO4-P)条件下旋链角毛藻和中肋骨条藻在不同浓度Pb(Ⅱ)条件下的生长曲线.实验结果表明,较低浓度Pb(Ⅱ)对旋链角毛藻和中肋骨条藻生长都有一定的促进作用,最佳促进藻类生长浓度分别为454,258,51;351,194,35μg·dm-3;高浓度Pb(Ⅱ)对它们的生长则表现为抑制作用,并且随着营养盐(NO3-N,PO4-P)浓度的增加,Pb(Ⅱ)对两种赤潮藻生长的抑制作用是逐渐降低的,营养盐(NO3-N,PO4-P)与Pb(Ⅱ)之间可能存在着拮抗作用. 相似文献
109.
Toru?Iwata Keiko?Yoshikawa Katsutoshi?Nishimura Yoshihisa?Higuchi Takao?Yamashita Shigeru?Kato Eiji?OhtakiEmail author 《Journal of Oceanography》2004,60(6):995-1000
The measurements of the vertical transport of CO2 were carried out over the Sea of Japan using the specially designed pier of Kyoto University on September 20 to 22, 2000. CO2 fluxes were measured by the eddy correlation and aerodynamic techniques. Both techniques showed comparable CO2 fluxes during sea breeze conditions: −0.001 to −0.08 mg m−2s−1 with the mean of −0.05 mg m−2s−1. This means that the measuring site satisfies the fetch requirement for meteorological observations under sea breeze conditions. Moreover, the eddy diffusivity coefficient used in the aerodynamic technique is found to be consistent with the coefficient used in the eddy correlation technique. The present result leads us to conclude that the aerodynamic technique may be applicable to underway CO2 flux measurements over the ocean and may be used in place of the bulk technique. The important point is the need to maintain a measuring accuracy of CO2 concentration difference of the order of 0.1 ppmv on the research vessels or the buoys. 相似文献
110.
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
Masahiko?FujiiEmail author Motoyoshi?Ikeda Yasuhiro?Yamanaka 《Journal of Oceanography》2005,61(5):803-815
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