青岛沿岸鸥类越冬习性的初步研究

有六种鸥类在青岛沿岸越冬，即红嘴鸥，黑尾鸥，银鸥，灰翅鸥，棕头鸥及灰背鸥。红嘴鸥和黑尾鸥是优势种，其群落多样性及均匀性指数均较低；鸥类日活动受潮汐的涨落，浮游生物的昼夜垂直迁移的影响较大。     

铰接式浮标性能研究

铰接式浮标作为一种新型助航标志越来越受到海监部门的欢迎。铰接式浮标具有良好的水动力性能，在风流中静倾角及在波浪中摇摆角都较小，而且定位准确。本文对铰接式浮标的结构及其水动力性能计算方法作了介绍，并在国家重点实验室──海洋工程实验室作了系列试验，得出一些有益的结果，为优化设计提供了依据。     

间断地形下的亚惯性频率地形波

在纯间断化地形的条件下,从理论分析和数值计算二方面探讨了亚惯性频率地形波的频散关系。指出正压亚惯性频率地形波的波模直接取决于间断点的个数和间断度。连续地形可以看成是纯间断地形的极限情况,因此,连续地形的起伏程度有类似间断度的作用。在对连续地形的频散关系进行数值计算时,水平步长的选取对计算结果有很大的影响。     

浅谈计算机机房布线与防雷

文章主要讲述机房在设计和施工中需要考虑与布线的关系以及应当注意的一些事项,是作者在工程实践防雷中对机房布线和防雷工作的一些认识,仅供参考。     

土壤中镉、铜伤害对水稻光谱特性的影响

本文讨论了水稻受重金属镉和铜污染伤害后的光谱反射特性的变化,为遥感监测污染提供基本依据。使用高分辨率光谱辐射计在自然状态下实地测量了受污染的水稻光谱特性,比采集叶片在室内测量更接近于实际情况,便于结合遥感图像进行定性和定量分析研究。 结果表明,镉和铜拌土生长的水稻在分蘖期受到的影响最明显,无论是在生理上还是在反射光谱方面变化都比较显著。因此,对水稻受重金属污染的遥感监测最佳时间为分蘖期,有效波段为0.54—0.58,0.64—0.69,0.74—0.80微米。综合对水稻光谱的各种分析方法,如波形分析,微分光谱,绿度指数和主成分变换等技术,水稻在分蘖期,对高浓度的监测效果较好,而对低浓度效果不甚明显。     

青藏高原盐湖卤水中溴的分布特征及来源初探

溴是完备工业体系的关键必备元素。盐湖卤水是溴的重要来源。青藏高原盐湖众多,富含钾、锂、硼等资源元素,开发潜力巨大。然而,目前针对青藏高原盐湖溴浓度、分布特征及其物源的研究仍然薄弱。本次研究采集了26个青藏高原盐湖表卤水样品并分析其溴浓度,进一步总结其他64个已报道盐湖数据,系统分析了青藏高原盐湖溴浓度分布特征,并进一步探讨了溴的可能物源。结果表明:青藏高原盐湖表卤水溴分布在0.5～246.8 mg/L之间,平均为41.1 mg/L,其中,碳酸盐型盐湖卤水平均溴浓度最高(47.0 mg/L),且集中分布在高原南部,而氯化物型盐湖平均溴浓度最低(30.1mg/L),盐湖溴浓度呈现自南向北降低的趋势;青藏高原盐湖中溴有多种来源,高原南部富溴盐湖溴的来源可能主要与热泉补给有关,而柴达木盆地盐湖高溴来源可能主要与深部地层水(如油田水、背斜构造裂隙孔隙水、砂砾孔隙卤水、气田水等)补给有关。     

Prevalence and risk assessment of antibiotics in riverine estuarine waters of Larut and Sangga Besar River,Perak

Antibiotics released into the environment through anthropogenic activities exert selective pressure,driving bacteria towards increasing antimicrobial resistance.The prevalence of antibiotics and the ecological risks posed in the riverine estuarine of Larut River and Sangga Besar River,which included wastewater effl uents from hospital,zoo,and poultry slaughterhouse sources were investigated.Solid phase extraction(SPE)followed by high-performance liquid chromatography tandem mass chromatography(HPLC-MS/MS)were used to extract and quantify the antibiotic residues from 22 antibiotics belonging to six major antibiotic classes(sulfonamide,macrolide,fl uoroquinolone,phenicol,trimethoprim,and tetracycline).Sixteen antibiotic residues were detected with concentrations ranging from limit of detection(LOD)to 1262.3 ng/L.Fluoroquinolones and macrolides were the most frequently detected compounds.Erythromycin,clarithromycin,and ofl oxacin detected in hospital and zoo effl uents posed a high risk to algae while tetracycline had low to medium ecological risks toward all the relevant organisms from aquatic environments(algae,invertebrate Daphnia magna,and fi sh).     

Progress and prospects of applied research on physical geography and the living environment in China over the past 70 years (1949–2019)

Physical geography is a basic research subject of natural sciences.Its research object is the natural environment which is closely related to human living and development,and China's natural environment is complex and diverse.According to national needs and regional development,physical geographers have achieved remarkable achievements in applied basis and applied research,which also has substantially contributed to the planning of national economic growth and social development,the protection of macro ecosystems and resources,and sustainable regional development.This study summarized the practice and application of physical geography in China over the past 70 years in the following fields:regional differences in natural environments and physical regionalization;land use and land cover changes;natural hazards and risk reduction;process and prevention of desertification;upgrading of medium-and low-yield fields in the Huang-Huai-Hai region;engineering construction in permafrost areas; geochemical element anomalies and the prevention and control of endemic diseases;positioning and observation of hysical geographical elements;and identification of geospatial differentiation and geographical detectors. Furthermore, we have proposed the future direction of applied research in the field of physical geography.     

Diatom Response to Global Warming in Douhu Lake,Southeast China

A large number of lacustrine sedimentary records indicate that global warming is the main factor leading to significant changes in diatom communities in lakes of the northern hemisphere.However,due to the intensification of human activities since 1850,some scholars have emphasized that the increasing lake trophic level may be the main reason for the changes in diatom communities.The debate is ongoing.In order to avoid falling into the complex relationship between diatom changes and the seasonal cycle that characterizes lakes in mid and high latitudes,we chose a lake located at a low latitude,where the relationship between diatoms and temperature is not indirect but direct.The diatom record spans the past ca.100 years and reveals that the abundance of Aulacoseira granulata increased from 1900 until 1985, replacing the previously dominant Aulacoseira ambigua.These changes are in agreement with the increasing trend in global temperature.Since 1985,the percentages of the small-celled Discostella stelligera and the benthic diatom Navicula heimansioides have increased,while Aulacoseira granulata has decreased.This latest shift is caused by further global warming.We conclude that warming is the main factor leading to changing diatom communities in Douhu Lake.     

基于半分析模型的波段最优化组合反演混浊太湖水体叶绿素a

内陆水体叶绿素a浓度定量反演是水质遥感的热点与难点.本文基于对内陆水体叶绿素a、悬浮物、溶解有机物与水分子的光谱特征分析,从半分析生物光学模型出发,利用太湖实测的水面 ASD 高光谱遥感数据三波段组合,进行迭代优化,得到与叶绿素浓度密切相关而受悬浮物与黄色物质影响小的最优波段组合模型,反演精度较高,其决定系数和均方根误差分别为 0.8358、3.816mg/m3,该方法可以有效地反演高浓度悬浮物主导光学特性的水体叶绿素a浓度.