海洋鱼类卵壳亚微结构的研究

在现代生物科学中,应用生物卵壳亚微结构的物种特异性进行分类研究已成为可行性现实。在海洋生物学研究中,曾发现海胆类未受精的卵壳层颗粒中即存在着眀显的物种特异性差别( L?nning,1967)。很多学者通过对鱼类卵细胞发生期间的亚微结构及卵壳形成的研究,证实在鱼类卵壳结构中亦存在特异性的种间差异,并认为这些差异与分类学、生物学及其区系分布有密切关系( Müller& Sterba,1963; Yamamoto,1963;G?tting,1966; Anderson,1967; Flügel,1967)。目前我国对鱼类卵壳( Egg chorin)结构的研究还鲜为人知,本文亦是首次通过对12种海洋经济鱼类受精卵的卵壳结构差别的探讨,为进行鱼类系统分类和系统发育研究提供科学依据。     

Identification of Pb sources in Yellow Sea sediments using stable Pb isotope ratios

Rapid economic developments in East Asian countries have inevitably resulted in environmental degradation in the surrounding seas, and concern for both the environment and protection from pollutants is increasing. Identification of sources of contaminants is essential to environmental pollution management. In this study, the provenance of anthropogenic lead (Pb), a major pollutant of Yellow Sea sediments, was determined for river mouth sediments, including those of the Changjiang, Huanghe, Han, and Geum Rivers, and for age-determined shelf core sediments through the measurement of Pb isotope ratios in the HCl-leached fraction using multi-collector inductively coupled plasma-mass spectrometry (MC ICP/MS). Anthropogenic Pb has accumulated in shelf core sediments since 1910, and its isotope ratios were estimated as 0.863–0.866 and 2.119–2.125 for ²⁰⁷Pb/²⁰⁶Pb and ²⁰⁸Pb/²⁰⁶Pb, respectively, from the mixing relationships of the two endmembers. River mouth sediments exhibited enough distinction in anthropogenic Pb isotope ratios to be discriminated: 0.874 (2.144) in the Huanghe, 0.856 (2.129) in the Han, 0.857 (2.122) in the Geum, and 0.854 (2.101) in the Changjiang for ²⁰⁷Pb/²⁰⁶Pb (²⁰⁸Pb/²⁰⁶Pb), respectively. Although isotope ratios of geogenic Pb in sediments dating before 1910 showed narrow ranges (0.842–0.845 and 2.088–2.100 for ²⁰⁷Pb/²⁰⁶Pb and ²⁰⁸Pb/²⁰⁶Pb, respectively), distinct isotope ratios in each core permitted source identification of sediments in the Yellow Sea based on geographic locations and the geogenic Pb of each river. By comparing the isotope ratios of the estimated anthropogenic Pb to source-related materials, the provenances of anthropogenic Pb in Chinese river sediments were presumed to be Chinese coal or ore, which is also a major source of atmospheric particulate Pb. The anthropogenic Pb in the shelf core sediments in the northern Yellow Sea originated from northern Chinese cities such as Beijing and Tianjin through atmospheric pathways. Pb isotope ratios indicated that Pb in Korean river sediments was characteristic of local Korean ores.     

Geochemistry and environmental effect of cadmium in the super-large Jinding Pb-Zn deposit,Yunnan Province,China

The Jinding Pb-Zn deposit in Yunnan Province is the representative of a Cd-enriched area and mining activities lead to the release of Cd into the hypergenic ecosystem, resulting in Cd pollution. The concentrations of Cd vary greatly from one type to another type of rocks in the mining district. In the host rock, Cd concentrations range from 50×10^-6 to 650×10^-6 with an average of 310×10^-6. In primary ores, Cd concentrations range from 14×10^-6 to 2800×10^-6 with an average of 767×10^-6. However, in oxidized ores, Cd concentrations are highest, varying within the range of 110×10^-6 to 8200×10^-6 , averaging 1661×10^-6. It is shown that the oxidized ores are the main carder and environmental source of Cd. Leaching test showed that Pb/Zn ores are easy to oxidize and thereafter release Cd and other harmful elements. These leached elements in the leachate may be precipitated rapidly in the order of Zn〉Pb〉Cd. As for the concentration distribution of Cd in the Bijiang River, it is estimated to be 15.7 μg/L Cd in water, 49.3 mg/L in suspended substances, and 203.7 mg/L in sediments. The average value of Cd in soil from the polluted area is 83.0 mg/kg. Natural weathering of Cd-rich rocks and minerals imposes a potential environmental risk on the aquatic ecosystem of the Bijiang catchment.     

RELATIONSHIP OF ECO-ENVIONMENTAL CHANGE WITH NATURAL EROSION AND ARTIFICIALLY ACCELERATED EROSION

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Sea surface temperature anomalies in the South China Sea during mature phase of ENSO

Based on the 18-year(1993–2010) National Centers for Environmental Prediction optimum interpolation sea surface temperature(SST) and simple ocean data assimilation datasets,this study investigated the patterns of the SST anomalies(SSTAs) that occurred in the South China Sea(SCS) during the mature phase of the El Ni?o/Southern Oscillation.The most dominant characteristic was that of the outof-phase variation between southwestern and northeastern parts of the SCS,which was influenced primarily by the net surface heat flux and by horizontal thermal advection.The negative SSTA in the northeastern SCS was caused mainly by the loss of heat to the atmosphere and because of the cold-water advection from the western Pacific through the Luzon Strait during El Ni?o episodes.Conversely,it was found that the anomalous large-scale atmospheric circulation and weakened western boundary current during El Ni?o episodes led to the development of the positive SSTA in the southwestern SCS.     

潜源划分进展及我国海域和邻近海域区划潜源划分问题研究

对于陆域地区,我国已进行5次全国范围大面积地震区划研究工作,获得了丰富研究成果.但对于海域地区地震区划的研究较薄弱,较少涉及海域潜源划分模型.随着经济发展,涉及海域地区的经济活动日益频繁,对海域地区潜源划分研究及进一步地震区划研究工作的需求越来越强烈.为此,详细介绍代表性国家在潜源划分方面采取的原则和方法,总结我国海域...     

Long-term Changes of Disinfection Byproducts in Treatment of Simulated Ballast Water

This study investigated the changes in concentrations of haloacetic acids (HAAs) and haloacetonitriles (HANs) as disinfection byproducts (DBPs) for differe     

1932年昌马地震构造力学特征探讨

１９３２年昌马地震构造力学特征探讨郭万武，张范民，邢成起，温增平（国家地震局兰州地震研究所，兰州）ＤＩＳＣＵＳＳＩＯＮＯＮＴＨＥＴＥＣＴＯＮＯＭＥＣＨＡＮＩＣＦＥＡＴＵＲＥＳＯＦ１９３２ＣＨＡＮＧＭＡＥＡＲＴＨＱＵＡＫＥＭｓ７．６￥ＧｕｏＷａｎｗｕ；...     

短路线岩石地球化学测量在地质工作中的应用

短路线岩石地球化学测量在地质找矿工作中是一种简便、快速、经济的方法之一,应用范围广,对解决某些地质问题能发挥较好的作用。此方法在构造地球化学与地质找矿中被实际应用,具有简便、快速经济等特点。