Human Settlements on the Northern Shores of Lake Aral and Water Level Changes

The shore of Lake Aral in Kazakhstan is a perfect area for studying the human adaptation strategy to past climate changes. New archaeological material, gathered along the northern shores during the expedition of the INTAS project CLIMAN, is briefly presented. Changes in settlement activity during the Atlantic and Subboreal are related to lake level changes of the Aral Sea. A previ-ously proposed lake level maximum needs to be revised. In particular the lake level stand at 72/73 m, with an assumed age of 5000 BP is definitely refused. Based on the presented data the maximum lake level most probably never reached beyond 57/58 mean average sea level (masl). Furthermore the regression during the 15^th–16^th centuries has been underestimated. It may have been lower than the present day level. Thus the present desiccation of the Aral Sea is historically not unique, as a similar regression, probably induced by man as well, has occurred at least once during history. A readjustment of the water level is, therefore, possible at any time.     

辽东湾近岸冰区生态环境初步调查研究

１９９６年１月２６－３１日，在辽东湾近岸冰区选设４个站位进行了一次内容较为全面的生态环境调查研究，其项目包括温度、盐度、ｐＨ、ＤＯ、ＣＯＤ、ＴＯＣ、ＰＯＣ、营养盐、微生物、叶绿素、浮游植物、浮游动物和度栖动物。结果表明，辽东湾近岸冰区营养盐含量丰富，叶绿素ａ含量较低，存在一定数量的浮游生物。海水中硝酸盐、铵盐和磷酸盐含量均为冰中含量的１．５倍左右，海水中硅酸盐含量是冰的４．１６倍，亚硝酸盐和叶绿素     

Subjective annoyance caused by indoor low-level and low frequency noise and control method

IntroductionItwasbelievedthatonlyhigh_levelnoisecouldcausenoisepollution.Theinfluenceoflow_levelnoisehasnotbeenwidelynoticed.Thisresearchdiscoveredthatundercertainconditionsthelow_levelnoise,especiallylowfrequencynoise,mayevencausehigherannoyanceresponse.…     

特殊区域和特别敏感海域

特殊区域和特别敏感海域是国际海事组织提出了两个环境概念。文中就这两个概念的定义、起源、鉴定的标准和程序以及适用的保护措施进行分析、论述，并提出自己见解。     

元江河谷热带坝区自然优势及其开发

元江河谷是我国云南省横断山脉中的干热河谷之一,属于热带半干旱河谷气候类型。具有丰富的热量资源和土地资源,但降雨量特少,生态环境脆弱,限制了多种热带作物的生长,长期以来未引起人们的重视。作者在该地区进行多年试验研究工作的基础上,从自然地理条件、生态环境,通过对比分析,论述了元江河谷热带坝区的自然优势。强调指出:该地区是我国发展优质紫胶--信德紫胶虫最理想的地方。从林业的发展方向与战略来考虑,指出今后元江河谷热带坝区的开发利用,主要是发展林业,走“生态林业”的道路。选择优质紫胶虫最好的寄主树滇刺枣作为造林树种,建立以滇刺枣人工林为主体的人工生态系统。     

海冰数值预报在海洋开发中的应用

９０年代以来，海冰数值预报的产品被应用到多种领域，如海上石油开发，海上交通运输，海洋工程及海洋环境保护等，并创造了良好的社会和经济效益。本文叙述了海冰数值预报在海洋开发中的应用，特别侧重于局部海区的冰模式，为海洋工程服务以及结冰海区溢油行为和归宿的模拟研究。     

舰船装备环境工程发展概况

论述了海洋工程所面临的严重挑战。阐述了舰船行业中舰船材料、构件的海洋环境腐蚀防护试验概况以及舰船机电设备环境试验、舰船海洋(含湖水)环境物理性能(电磁、水声、水压等)测试和海洋风、浪、流等海洋环境观测和试验发展概况。     

天津地区霾天气特征研究

基于2014~2017年天津地区PM_2.5质量浓度，能见度和相对湿度监测数据开展霾天气特征研究.结果表明：天津中度以上霾过程分为五类：高压后部型，北部弱高压型，低压槽型，均压场型和锋前低压型.在现行标准下，中度霾一般对应重度污染天气，重度霾对应重度到严重污染天气；五级重度污染天气一般有中-重度霾发生，六级严重污染天气有重度霾天气发生.2013年“大气污染防治行动计划”开展以后，天津PM_2.5质量浓度和霾日均显著减少，2017年相比2013年霾日减少了55%，中度及其以上霾日由2013年的41d下降到2017年的20d，下降幅度超过50%.基于实况监测的PM_2.5质量浓度，能见度和相对湿度，可以较好的构建区域能见度计算方程.统计数据显示，其估算的能见度和实况值相关系数为0.94，相对误差为18.6%，非霾日辨识准确率为85%，霾日辨识准确率为95.6%，轻微霾辨识准确率为83%，轻度霾辨识准确率为78%，中度霾辨识准确率为93%，重度及以上霾辨识准确率为94%，对于判断霾等级，有较强的适用性.将该方程与空气质量模式结合开展霾等级预报，2015~2017年24h预报产品检验显示：能见度预报值与实况值相关系数为0.75，预报均值13.9km，实况均值14.1km，相对误差为29.6%，FAC2（预报值在实况值两倍范围内百分比）为98.1%，霾日预报准确率81.4%，霾日漏报率18.6%，霾日空报率20.6%，如果容错1级，轻微霾日预报准确率为96%，轻度霾日预报准确率为85%，中度及以上霾日预报准确率为69%，可有效支撑天津霾等级预报的开展.     

基于洪水资源化的水库汛限水位调整及其风险管理

在论述“洪水资源化”概念和调整水库汛限水位所涉及的影响因素的基础上, 构建了汛限水位 调整后的风险和效益评价指标体系及其估算方法, 以及论述了水库汛限水位调整的风险管理对策。 以五强溪大型水库为例, 综合评价了在不同汛限水位方案下所带来的风险及效益, 并引入优选模糊 理论方法来合理调整汛限水位。通过综合分析认为, 五强溪水库在主汛期将汛限水位从现行的 98.00m 提高到100.00m 的方案是可行的, 它在防洪风险增加不多的情况下, 可将有可能被排泄的 1.85×108m3 洪水转化为有效利用的水资源, 显然, 将大型水库提高汛限水位超蓄洪水是实现洪水资 源化的重要手段, 但必须是在加强水库实时调度风险管理的提前下实施。     

Nitrogen accumulation and plant species replacement in three salt marsh systems in the Wadden Sea

Salt marsh development on the coastal barrier island of Schiermonnikoog (The Netherlands) was compared with two other salt marsh systems in the Wadden Sea. Accretion rate, nitrogen accumulation and changes in plant species composition were investigated using chronosequences. The age of the marsh was estimated from aerial photographs and old maps. In 7230 plots, the elevation of the marsh surface, the thickness of the sediment layer (clay) and the presence of plant species was recorded. In addition, the nitrogen pool was measured at each successional stage. Accretion rates were similar in the three salt marshes. Higher accretion rates were found at younger marshes. A strong linear relationship between nitrogen pool size and thickness of the clay layer was found for the three marshes. The accumulation rate of nitrogen is therefore strongly related to the accretion rate. Thus, more nitrogen is present in the sediment of later successional stages where more clay has accumulated. On the high salt marsh (55 cm+MHT),Ameria maritima disappeared andArtemisia maritima, Juncus gerardi andElymus athericus established at sites with a thicker clay layer. On the low salt marsh (25 cm+MHT),Plantago maritima, Puccinellia maritima andLimonium vulgare disappeared andAtriplex (Halimione) portulacoides established. Apparently, with the accumulation of clay and therefore of nitrogen, tall growing species take over in salt marshes not grazed by livestock.