湖州市土壤磁化率与重金属元素分布规律及其相关性研究

通过对84个地表土样、17个剖面土样和11个基岩样的磁参数与化学分析测试,对湖州市进行了土壤磁化率与重金属元素分布规律、成因及两者的相关性研究.结果表明:表层土壤磁化率高值异常区与土壤重金属元素高值分布区吻合程度非常高,剖面土壤磁化率值与重金属元素含量总体上均呈向下递减的相同特点;表层土壤磁化率与重金属元素高值异常均系人类经济工程活动影响所致,主要与当地城镇生活垃圾随意堆放、垃圾施肥、工业粉尘、废气、废物和污水排放、农药和化肥的过量使用等有关;表层土壤磁化率值与重金属元素Cd、Hg、Pb、As和Cr含量之间在不同环境条件下相关性有着明显的差异.在旱地土壤中磁化率与重金属元素Hg、Pb高度相关,与Cd、As和Cr不相关;在水田土壤中磁化率与重金属元素Pb、As高度相关,与Cd显著相关,而与Hg、Cr不相关.     

从磁铁矿的某些特征看闽西南地区马坑式铁矿的成因

我们为进一步了解马坑式类型矿床的成因,故对该铁床的主要矿石矿物——磁铁矿的某些特征进行了一些研究。现将我们的研究成果整理成文,供参考。本文由王文斌、王润华执笔,文中不妥和错误之处,请批评指正。     

南京地区新近纪地层排序及其时代

南京地区新近纪地层发育较齐全,生物化石丰富,根据哺乳动物化石最新研究成果,并通过地层对比,将其厘定为中新世早—中期洞玄观组(N1-21d)、中新世晚期的六合组(N31l)和黄岗组(N31h)以及上新统的尖山玄武岩组(N2j)。长江坳陷中砾石层相当发育,如南京附近的雨花台砾石层,安徽境内的安庆砾石层,主要由三套岩性组成,之间均呈假整合接触。第一套归属于六合组(N31l),第二套沿用雨花台组(N2y),第三套为更新统。     

Ocean urea fertilization for carbon credits poses high ecological risks

The proposed plan for enrichment of the Sulu Sea, Philippines, a region of rich marine biodiversity, with thousands of tonnes of urea in order to stimulate algal blooms and sequester carbon is flawed for multiple reasons. Urea is preferentially used as a nitrogen source by some cyanobacteria and dinoflagellates, many of which are neutrally or positively buoyant. Biological pumps to the deep sea are classically leaky, and the inefficient burial of new biomass makes the estimation of a net loss of carbon from the atmosphere questionable at best. The potential for growth of toxic dinoflagellates is also high, as many grow well on urea and some even increase their toxicity when grown on urea. Many toxic dinoflagellates form cysts which can settle to the sediment and germinate in subsequent years, forming new blooms even without further fertilization. If large-scale blooms do occur, it is likely that they will contribute to hypoxia in the bottom waters upon decomposition. Lastly, urea production requires fossil fuel usage, further limiting the potential for net carbon sequestration. The environmental and economic impacts are potentially great and need to be rigorously assessed.     

一个关于临界地城的临界区域判别的方法

由临界地震的概念和外推Ｂｏｗｍａｎ等人关于孕育未来的地震半径的思想,发展出一个临界圆重叠方法来地寻找未来强震的临界区域位置,模拟实验的对比检验表明这种方法是有效的,使用主震前一定时间内地震目录,这个方法能找出临界区域,而未来震中位置将位于临界区域内或其边缘。使用新西兰和中国新疆南部的中强震目录检验,该方法可以在震前较准确地定位出强城的临界区域位置,使用中国１９９５年至１９９９年８月的小震目录,给出     

Possible ecological consequences from the Sethu Samudram Canal Project, India

The Sethu Samudram Canal Project (SSCP), considered as a harbinger of economic growth in India, is a mega engineering project being developed to provide a 260 km long, 300 m wide and 12 m deep shipping channel between the Arabian Sea and the Bay of Bengal. This project impacts the unique biota and biodiversity of a 10,500 km(2) Marine Biosphere Reserve. This man-made link facilitates exchange of water masses between the less saline Bay of Bengal and the more saline Arabian Sea. Initial construction, subsequent dredging for channel maintenance, and the associated ship traffic would result in irreversible changes to the already over-exploited and stressed environment. Additionally, the channel would form a deep ocean route for future tsunamis. However, to provide assurance to the public, particularly the 50,000 fishing folk, in 47 villages in this area, it would be crucial that a long-term environmental monitoring program is instituted. A thorough evaluation of the impending environmental impacts, similar to those addressed by a Before/After and Control/Impact (BACI model) is recommended.     

长江三角洲地区第四纪磁性地层学研究

根据长江三角洲地区18个新老钻孔的古地磁、磁化率、天然剩余磁化强度等磁性特征的综合研究，证明布容正向极性带、松山反向极性带与高斯正向极性带，以及哥德堡、布莱克、贾拉米洛、奥尔杜维极性亚带在本区都存在；结合岩石地层、生物地层和测年数据等资料，与微古、孢粉等分析结果都有一定的吻合性；这对第四纪地层的划分具有重要的参考价值。同时认为，第四纪时长江三角洲地区继接受碎屑沉积物以来，基本表现为一连续沉积区，并无长时间的大规模沉积间断。