Sedimentary records of black carbon in the sea area of the Nansha Islands since the last glaciation

Core 17962 taken from the sea area of the Nansha Islands recorded a sedimentary history of more than 30 000 years. The black carbon data from the core, which can inform us of the history of vegetation fires, show that during the last glaciation, especially during the last glacial maximum at about 18 kaBP, the fluctuation of the concentration and accumulation rate of the black carbon was relatively great, whereas it was small during the Holocene. The isotope composition of the black carbon indicates that the precursors of black carbon were mainly grasses from the last glaciation to the Holocene. The sub-alpine and alpine vegetation zones covered mainly with grass and bush on the lands around the southern South China Sea were probably the sources of black carbon. The altitudinal vegetation changes from the last glaciation to the Holocene gave rise to the changes of the sedimentary characteristics of black carbon.     

南麂列岛海域硅藻和甲藻群落的分布特征

于2006年4月~2007年3月采集浙江南麂列岛海域水样,研究了硅藻和甲藻群落在该海域的种类组成、生态分布特征和季节动态.共鉴定浮游植物93种,其中硅藻35属68种,甲藻11属21种.南麂海域浮游植物细胞丰度较高,年平均细胞丰度达到3.19105cellsL-1.硅藻集群的高峰区主要集中在夏季和秋季,细胞在表层水体的含量高于底层水体,调查期间共记录硅藻赤潮事件1起,发生于2006年8月,优势种类是中肋骨条藻.甲藻赤潮仅在春季（5月）发生,优势种类为原甲藻种类,包括三角棘原甲藻和东海原甲藻,分别在5月中旬和5月下旬先后引发赤潮,甲藻在表层水体含量高于底层水体.     

LC4铝合金在热带海洋大气环境中的早期腐蚀行为

通过现场暴露实验,研究了LC4铝合金在西沙群岛典型热带海洋大气环境中暴露个月和3个月后的腐蚀行为和规律.采用扫描电镜观察了腐蚀产物的表面和断面微观形貌,并用能量色散谱(EDS)、红外光谱(FTIR)和X射线光电子能谱(XPS)分析了腐蚀产物元素和组成.测试了LC4铝合金腐蚀后的极化曲线和电化学阻抗谱.实验结果表明:LC4铝合金在西沙海洋气候环境中暴露1个月和3个月后发生了明显的局部腐蚀,Cl-是促进点蚀发生的主要原因.腐蚀产物中主要包含氧、钠、铝、硅、钙、氯、硅等元素,主要腐蚀产物为Al_2O_3.3H_2OAl(OH)_3、AlOOH、AlCl_3等.随大气暴露时间延长,腐蚀电流密度减小,表明腐蚀产物对基体有一定的葆护作用.     

海南海岛生态旅游资源开发与保护

海南省有2×10~7km~2海域,拥有600多座岛屿,其具有丰富的生态内涵,宜人的气候环境,奇异的红树林、珊瑚礁景观,生动的地貌景观,多姿多彩的人文景观,浓郁的美学意境等特征,为开展海岛生态旅游提供了良好的基础;可开展森林旅游、科学考察旅游、野生动植物观赏旅游、体育旅游、度假旅游等多种旅游项目。通过开展生态旅游,实现经济效益目标和生态环境目标的统一,即岛屿旅游资源的可持续利用。     

浙江常山国家地质公园芙蓉峡河段河流袭夺现象研究

芙蓉峡是常山国家地质公园内一具独特地貌景观的山区河段-狭窄的河床、陡峭的谷坡和宽广的阶地.本文从地貌、沉积、年代和构造四方面对导致该景观的地貌事件,从事件过程、事件发生时间和事件发生原因等方面进行了初步调查研究.研究结果显示：正是由于芳村溪袭夺了金源溪上游及所引发的河流强烈下切,才形成了芙蓉峡段这种地貌景观;这次河流袭夺发生的年代估计在52.38~33.6 ka B.P.期间,发生的原因可能与区域一NE向断裂在这期间的一次强烈活动有关.     

菲律宾“领海基线法”之剖析

菲律宾总统阿罗约签署的“领海基线法”,将南中国海部分岛屿划入其中,严重损害了中国的主权,不仅违背了历史事实,而且违反了国际法的基本原则。菲此举之目的是盗用国际法逞其扩张私欲、转嫁国内矛盾、借“安全”名义攫取海洋资源等。中国应采取加快经济发展、加强国防建设、保持台海稳定和展开外交攻势等策略,维护自己的海洋权益。     

Two new species of the commensal shrimp genus Periclimenaeus Borradaile, 1915, (Decapoda,Palaemonidae) from the Maldive Islands

Two new species of the commensal shrimp genus Periclimenaeus Borradaile, found in the waters of the Maldive Islands, Indian Ocean, are described and illustrated. P. tchesunovi sp. nov. is related to P. rastrifer Bruce. The former may be distinguished by its deeper rostrum, with dentition 6/1, the presence of supraorbital tubercles, and broad, spatulate fingers on the first pereiopods. P. zarenkovi sp. nov. closely resembles P. diplosomatis Bruce in the presence of minute denticulations on the dactylar cutting edge of the major second pereiopod, but differs from it by a deeper rostrum with 5 dorsal teeth, more robust chelae of the second pereiopods, and small dorsal telson spines.