Numerical study of the seasonal salinity budget of the upper ocean in the Bay of Bengal in 2014

Impact factors on the salinity budget,especially the eddy salt fluxes and smaller-scale diffusive salt fluxes for the upper 50 m of the Bay of Bengal(BoB) in 2014 are investigated using a box model based on the Regional Ocean Modeling System(ROMS) daily outputs.The model results reproduce that the precipitation and river runoffs are the dominant factors modulating the sharp salinity decrease during the summer monsoon season.The analysis shows that the salinity increase after the summer monsoon is mostly due to the meridional advective and diffusive salt fluxes.The vertical advective salt flux,which is sensitive to the different signals of the wind stress curl,plays an important role in balancing the salinity change induced by the meridional advective salt flux during both the summer and winter monsoon seasons.Distinctive spatial mesosc ale structures are presented in the eddy salt flux throughout the year,and their contributions are sizeable(over 30% in the meridional direction and about 10%-30% in the vertical direction).The meridional eddy salt flux is larger in the monsoon seasons than that in the inter-monsoon seasons,and in a positive pattern near the western boundary during the winter monsoon and autumn inter-monsoon.The vertical eddy salt flux makes an important contribution to the salinity budget,especially along the coastal area and around the Andaman and Nicobar Islands.The vertical eddy salt flux becomes large when a tropical cyclone passes the area.     

瞬变电磁法在煤矿断层导水性勘查中的应用

煤矿断层导水是引起煤矿水害问题的主要因素之一,对煤矿断层的导水性勘查与评价是煤田水文地质研究中的重要课题,也是煤矿采区布置与安全开采必须解决的问题。在煤矿开采初期查明矿区内断层构造的空间分布及其含导水性,对指导煤矿安全生产具有重要的意义。在充分收集新安煤矿矿区地质、水文及物探资料的基础上,利用瞬变电磁技术,对区内断层等构造的含导水性进行了勘查,取得了良好的效果,为煤矿的开采设计和施工提供了参考依据,有效地预防了煤矿开采过程中安全事故的发生。     

20世纪90年代中国东西部土地利用变化时空特征分析

在覆盖全国的1km栅格土地利用本底与动态成分数据时空信息平台支持下,应用土地利用动态度模型,分别计算了全国及东西部地区土地利用一级类型的单一和综合动态度,并分析了土地利用动态度的空间格局。通过分析东西部土地利用类型变化特征和土地利用类型转换特征,对20世纪90年代中国东西部土地利用变化过程的时空特征进行了全面分析,揭示了东西部地区土地利用变化的时空规律。并对主要土地利用类型变化的原因进行了分析。     

Assessment of Habitat Suitability in the Upper Reaches of the Min River in China

Habitat richness influences and even determines biological diversity. Plant habitat suitability assessment can provide technical guidance and information support for ecological restoration. Thirteen factors in three categories of terrain, meteorology and soil were chosen to build a habitat suitability assessment index framework in the Upper Reaches of the Min River, based on the local natural environment and the actual influencing factors of vegetative growth. Combined with the Analytic Hierarchy Process(AHP) and entropy method, which were used to calculate weights of indexes, habitat suitability was studied by using a multi-objective linear weighting model and geographic information systems(GIS) spatial analysis techniques. The assessment results are as follows: Altitude, soil stability, aspect and slope have more important effects on plant habitat suitability in the Upper Reaches of the Min River, and their weights are 0.311, 0.260, 0.198 and 0.125, respectively. Suitable and sub-suitable habitats cover 4431.80 km2 and 6171.12 km2, respectively; most of which are distributed along both sides of rivers and have higher suitability. Unsuitable habitats cover the largest area(6679.76 km2), accounting for 29.83% of the whole area; and the worst unsuitable habitats are 5107.23 km2(22.81%); they account for more than half of the studyarea. These results indicate that the plant habitat in the Upper Reaches of the Min River is poor and ecological restoration is both urgent and difficult. Therefore, based on the principle of taking measures suitable to the habitat in ecological restoration projects, ecological and engineering measures should be combined to have better effects, while increasing the strength of ecological protection.     

Changes in the network of tourist trails in the border zones of the Czech Republic after entering the Schengen area

Among the factors influencing tourist trail network development are political issues, including the presence of state borders, the possibility of crossing them and the accessibility of border zones. In the article, it was decided to look at changes in the offer of tourist trails(hiking and cycling) along the entire border of the Czech Republic after the extension of the Schengen area(within this area, crossing the border is possible anywhere, and not only at official border crossings). It should be emphasized here that the borders of the Czech Republic over most of their length run through mountainous areas and, apart from political factors, natural features should have a major impact on the development of tourist routes. In order to determine the coherence of the current network of trails on both sides of the Czech Republic state border, modern tourist maps have been analyzed, determining the number of places where it is possible to cross the state border with the help of a marked tourist trail. Based on that, two indicators were introduced to determine the degree of openness with all neighboring countries as regards the opportunity to cross on a tourist trail. Changes in the historical situation, a comparison of the accessibility of the border area before entering the Schengen area and 2019, were analyzed for two study areas using archival maps. Over a decade after the extension of the Schengen area, the number of places where tourist trails of neighboring countries approach the border has clearly increased. Crossing is more often made possible using hiking trails than cycling routes(trails of the first type cross the border every 7.91 km, while the latter every 13.3 km), but considering the speed of movement, it can be assessed that the openness for cyclists is higher than for hikers. Moreover, in many places there is still significant potential for further integration of tourist trail networks as trails created in one country often do not have a continuation on the other side of the border.     

Characteristics of the transition Layer in the South China Sea in 1998

CTD data on standard levels coolected during July and December in 1998 and the cubic spline interpolating method were used to study the characteristics of the transition layer temperature and salinity.The thermocline undergoes remarkable seasonal variation in the South China Sea (SCS),and especially in the region of the north shelf where the thermocline disappears in december.The thermocline is stronger and thicker in July than in December,There is no obvious seasonal variation in the halocline.Due to the upper Ekman transport caused by monsoon over the SCS,the thermocline slopes upward in July and downward in december from east to west in the northern SCS.The characteristics of the thermocline and halocline are influenced by local eddies in the SCS.The Zhujiang diluted flow influences significantly the SCS shelf‘s halocline.     

The influence of the sea-air heat exchange over the Kuroshio in the East China Sea in winter on the precipitation in the middle and lower reaches of Changjiang River in flood season

In this paper, the sea-air heat exchange over the Kuroshio in the East China Sea during the winters of 1954–1972 is computed and analysed. The results indicate that the year to year anomalies of sea-air heat exchange are obvious and the values are mainly controlled by the intensity of the cold air at the same time. The authors have found a close relationship between sea-air heat exchange and precipitation in the region of the Changjiang River during the early summer. Finally, the predicting indication for forecasting this precipitation around the middle and lower reaches of Changjiang River in June is given. Contribution No. 839 from the Institute of Oceanology, Academia Sinica. This paper was published in Chinese inOceanologia et Limnologia Sinica 14 (3): 256–262, 1983.     

Contrast between the climatic states of the warm pool in the Indian Ocean and in the Pacific Ocean

Based on the analysis of Levitus data, the climatic states of the warm pool in the Indian Ocean (WPIO) and in the Pacific Ocean (WPPO) are studied. it is found that WPIO has a relatively smaller area, a shallower bottom and a slightly lower seawater temperature than those of WPPO. The horizontal area at different depths, volumes, central positions, and bottom depths of both WPIO and WPPO show quite apparent signals of seasonal variation. The maximum amplitude of WPIO surface area’s seasonal variation is 58% larger over the annual mean value. WPIO’s maximum volume variation amplitude is 66% larger over the annual mean value. The maximum variation amplitudes of the surface area and volume of WPPO are 20.9% and 20.6% larger over the annual mean value respectively. WPIO and WPPO show different temporal and spatial characteristics mainly due to the different wind fields and restriction of ocean basin geometry. For instance, seasonal northern displacement of WPIO is, to some extent, constrained by the basin of the Indian Ocean, while WPPO moves relatively freely in the longitudinal direction. The influence of WPIO and WPPO over the atmospheric motion must be quite different.     

DTM在高黎贡山羚牛潜在生境研究中的应用

本文建立了高黎贡山自然保护区北段范围的数字地形模型,并将其应用在濒危珍稀动物——羚牛潜在生境评价研究中。通过叠加羚牛活动区的海拔高度、坡度及植被类型,获得了羚牛的潜在生境区,结合羚牛的生态习性与实地调查资料,选择海拔高度、坡度、植被因子3个指标对其潜在生境的适宜性进行了划分和评价。结果表明:在没有人类活动的影响下,羚牛可在研究区内大部分地区生存。从1974￣2004年,适宜羚牛生存的各等级生境面积逐年减少,而不适宜生境的面积逐年增加。     

近30年西北太平洋热带气旋时空特征分析

 本文利用近30年热带气旋年鉴建立了西北太平洋热带气旋灾害数据库,以.NET和ArcGIS Engine搭建了二次开发平台(其包括登录界面、图查属性、 属性查图、数据库分析处理等功能),分析了西北太平洋热带气旋的时间特征、空间特征,以及时空变化特征。结果表明,30年来西北太平洋共生成905次热带气旋,年均30.2次/年。其中,7-10月最容易发生热带气旋,占所有热带气旋的35.7%,8月份达到峰值,达21.5%,2月最不容易发生热带气旋,发生频率仅为0.6%,而8-10月是强台风和超强台风发生的月份。热带气旋源地集中区位于(10°~22°N,112°~120°E)、(8°~20°N,126°~134°E)和(6°~20°N,136°~150°E),具有纬度带和经度带的分布特性。源地的空间分布存在明显的季节变化和月变化特征,在季节尺度上,夏季主要集中在偏北偏西位置,并向南向东偏移,冬季向北向西偏移;在月尺度上,1-4月源地相对分散;5-6月相对于1-4月的源地位置发生向西向北方向转移;7月向东向北扩散,8-9月向西扩散,9月源地相对集中,10月热带气旋源地南移, 11-12月热带气旋源地范围明显减小。     

Observation of currents in the southern Yellow Sea in the summers of 2001 and 2003

Long term current observations in the southern Yellow Sea are very scarce because of the intense fishing and trawling activities. Most of the previous studies on tides and circulation were not rigorously validated with direct current measurements. In this study, tidal and sub-tidal currents were examined using current profiles from three bottom-moored Sontek Acoustic Doppler Profilers （ADPs） deployed in the southern Yellow Sea in the summers of 2001 and 2003. The measured current time series were dominated by tidal currents. The maximum velocities were between 40-80 cm s^-1 at the mooring stations. The M2 current was the dominant primary tidal constituent, while the MS4 and M4 components produced the most significant shallow water tidal currents with much weaker amplitudes. The measured mean sub-tidal velocities were less than 5 cmsl. The mean flows in the lower layer implied that an anti-cyclonic circulation pattern might exist in the deeper central Yellow Sea. However, the previously expected cyclonic circulation pattern in the upper layer was not clearly shown by the observations.     

长江中下游持续性异常降水的天气学特征分析

针对长江中下游持续性降水的研究多为个例诊断,很少从合成的角度考虑,利用长江中下游地区89站的1961~2011年的逐日降水资料和NCEP/NCAR逐日再分析资料,采用数理统计和合成分析的方法,统计长江中下游地区夏季持续性降水事件,并合成分析了其环流特征。结果表明:1961~2011年,长江中下游地区夏季持续性异常降水事件发生了50次,主要集中在6月和7月,长江中下游地区持续性异常降水事件平均每2~3年发生一次。厄尔尼诺次年多有持续性异常降水发生;长江中下游地区持续性异常事件发生时,总伴有环流场的异常调整,低纬西太平洋副热带高压西伸,南北经向风在长江流域交汇,高层上,南亚高压东移,长江中下游地区出现强的辐散中心,为异常降水提供了重要条件。水汽来源主要是索马里越赤道气流途径暖湿的阿拉伯海,孟加拉湾和我国南海北部,进入长江中下游地区。     

新时期中国电影娱乐化趋势的原因探析

近期中国电影艺术娱乐化趋势的原因,可以从电影生产链条中的市场、生产者和消费者三个方面进行探究。一是社会转型期电影的产业化发展、市场的激烈竞争和票房的功利追求的必然结果,二是源于电影生产者对电影市场化的探索和艺术创作意识的模糊,三是大众文化氛围下观众娱乐消遣的需求。正确认识电影娱乐化这一现象,理解电影的娱乐性和商业性、艺术性的关系,有助于电影艺术的发展。     

华南沿海陆域石油资源远景分析

本文首先论述了华南与周边的地质构造分野,着重阐述了大别-舟山造山带的依据。文章分析了基底构造的基本特点及沿海陆域的地壳典型结构;重点阐述了该区中生代以来的印支运动、兰江运动、闽浙运动、丽水运动和狭义的燕山运动等地质事件的主要特点及表现形式;文章依据有利的7个含油（气）层位,以及构造变格所造成的盆地模跨规律等,提出了三个含油（气）远景区。     

THE PROTECTION OF THE ECOLOGIC ENVIRONMENT OF THE GREEN CORRIDOR IN THE LOWER REACHES OF THE TARIM RIVER

The Green Corridor in the lower reaches of the Tarim River is not only a unique natural landscape in desert but also an important passageway. Nowadays, the ecologic environment of the corridor is getting worse and worse due to man's economic activities and the lack of knowledge of the importance of the environment, which is one of is the three environment problems in Xinjiang. The corridor is in great need of planning and managing.     

The role of railroad in the development of the american west

This paper explores the role of geographical expansion of railroads, one of the most important Fransportation vehicles, in the history of American west development, analyses its implication on the unprecedented migration movement and the resulted urbanization in the west and concludes with the fact that the appropriate interference by the government, especially in the early period, is vital to regional development practice, because of market failure at the initial stage, infrastructure construction conducted by the government always plays as the first impetus to any regional development process. Only through this bridge, can some physical factors, such as population, be attracted to feed the backward area. As a result, cities grow fast and the region develops well. The experience can be shared by all countries. Besides reviewing the history of west development in America, focusing on the relationship between railroads expansion and urban growth, which was realized through population migration. A comparison on the particular pattern of regional development between U. S and China is made as well at the end. It is noted that despite of the common first impetus, government subsidies and the common final result, urbanization, the path for the America is bottom-up, whereas that for China is top down, that is to say, development should originate from big cities, then to towns, and finally radiate into rural areas.     

地缘政治经济背景下中老-中越边境地区橡胶林时空扩展特征研究

国家间地缘政治经济关系正在驱动区域土地利用变化,边境地区首当其冲。20世纪90年代以来,全球橡胶市场的强劲需求以及中南半岛与域外国家40多个地缘经济合作机制的实施,引起了包括中国与老挝(以下称“中老”)-中国与越南(以下称“中越”)边境地区橡胶林扩展种植在内的显著土地利用变化。基于此,利用Landsat影像构建的橡胶林落叶-新叶萌生期内植被-水分指数(Renormalized Vegetation Index, RNVI)组合算法,获取中老-中越边境地区1990年代以来中老、中越地缘政治经济关键节点的橡胶林种植信息,进而揭示中老、中越地缘政治经济关系对其边境地区橡胶林扩展的影响及其国别差异。结果表明:(1)在“替代种植”与边境农林合作等地缘政治经济影响下,中老-中越边境地区橡胶林种植面积由1992年的995.5 km²增加至2018年的5537.7 km²,增长近4.6倍,且呈明显的沿边性和跨境性;(2)随着中老磨憨-磨丁口岸开通、中老北部九省合作机制构建等,1992—2018年,中老边境沿线30 km缓冲区内橡胶林种植面积从244.7 km...     

湖南常德-安仁断裂印支期构造运动分段性: 来自花岗岩的约束

常德-安仁断裂是湖南东部一条NW向大断裂。以大量的基础地质资料为基础,对该断裂的分段性特征进行了总结;基于断裂带印支期花岗岩成因及分布规律,提出其在中三叠世晚期印支运动主幕中的活动具有分段性。根据断裂带及其两侧地区构造特征以及出露地层和岩浆岩等方面的差异,将常德-安仁断裂分为安仁-衡山段（Ⅰ）、湘乡段（Ⅱ）、桃江段（Ⅲ）、常德-石门段（Ⅳ）4段,各段间以穿切深部地壳乃至地幔的NE向深大断裂为界。NE向深大断裂主要形成于加里东运动并具左行走滑,其将常德-安仁断裂切错为互不连通的多段,导致后者在中生代的构造运动具分段性。区域上晚三叠世花岗岩主要为后碰撞环境下深部地壳熔融形成的S型花岗岩。常德-安仁断裂带上晚三叠世花岗岩的分布特征指示该断裂在印支运动主幕中的活动具有明显的分段性:中三叠世印支运动主幕中断裂湘乡段深部发生剪切活动,在端部受限的条件下其运动幅度、剪切强度及相应的增温效应自该段中部向端部减小,导致晚三叠世的深部地壳减压熔融仅发生于湘乡段中段,相应的花岗岩体则出露于湘乡段中段和北段。这一构造-岩浆机制在安仁-衡山段和桃江段得到同样反映。常德-安仁断裂在印支期的分段运动,是先期贯通断裂被NE向深大断裂切错为多段后产生的"被动性"分段运动,有别于-般的多条小断裂发生、扩展并最终连接为一条大断裂的"主动性"断裂分段运动或分段生长。      

南堡凹陷东北部东二段重力流砂岩储层发育规律

随着勘探程度的提高,深水重力流成因的浊积岩储层已成为我国东部断陷湖盆油气勘探开发的重要目标之一。因为沉积分异不足和成岩破坏,重力流砂岩的储层质量通常整体较差,优质储层的预测成为制约其有效油气勘探的关键地质因素。利用岩心、测井资料及储层物性、岩石薄片分析结果,研究了南堡凹陷东北部东营组二段重力流砂岩的岩相特征、成因类型、储层特征,以探索优质储层的控制因素和发育规律。研究表明,区内重力流沉积可细分为8种岩相,解释为滑动滑塌、砂质碎屑流、泥质碎屑流、浊流4类成因。储层物性参数统计分析证实,本区重力流砂岩储层非均质性强,储层质量受控于砂岩成因、砂-泥结构及其影响的溶蚀强度。从成因看,砂质碎屑流和浊流对重力流砂岩优质储层的发育贡献最大。砂质碎屑流成因的块状砂岩厚度较大、泥岩夹层较少、钙质胶结物的溶蚀程度高,储层质量最好;而浊流成因的砂岩厚度较薄,与泥岩呈互层或夹层产出,成岩环境封闭、钙质胶结物溶蚀程度低,储层质量较差。本研究为湖盆深水重力流砂岩油气的高效勘探开发提供了一种基于成因和结构的储层预测思路。     

Microbial diversity in the sediments of the southern Mariana Trench

Microbial diversity in the abyssal sediments beneath the seafloor of 30, 94, and 151 cm near the southern end of the Mariana Trench was analyzed in the Illumina HiSeq 2500 platform. Results show that the microbial populations were dominated by bacteria but merely no archaea were identified at the three depths. In the bacterial community,Proteobacteria and Firmicutes dominated the total taxon tags, followed by Bacteroidetes, Actinobacteria, Planctomycetes, Cyanobacteria, and Chloroflexi, which together account for over 99% of the total population. Similar to that in the seawater in the trench, the operational taxonomic units(OTUs) belonging to Gammaproteobacteria from the sediment samples showed high abundance.However, common bacterial OTUs in the water of the trench including Nitrospirae and Marinimicrobia were hardly found in the sediments from the southern Mariana Trench or the hadal region. Therefore, this study documented for the first time the compositions of microbial diversity in the trench sediments, revealed the difference in microbial diversity in water and sediment of the trench and will enrich the knowledge on the microbial diversity in the abyssal areas.