潮间带小海湾围堤对湾外水下岸坡的影响

分析了杭州湾北岸一个潮间带小海湾－炮台湾及其前沿海域的流场、含沙量分布及水下地形的变化，指出小海湾内水流主要受湾外浅水水流控制，在独特的边界地影响下，湾内在不同时段内出现历时较短的水平环流，流场变化较快，小水深时水体含沙量较高，含沙量随水深和水流和变化而急剧变化。对湾外浅水水域水流的挟沙力了计算，并讨论了炮台湾围堤后水流挟沙力的变化，给出围堤后水下岸坡剖面变动的预测，经与实测比较，结果是令人满意的     

建筑物上侧击雷电的三维数值模拟

基于三维近地面闪电先导发展随机模式,通过改变先导初始电位和建筑物几何特性,分析各种情况下的侧击雷电发生概率,探讨侧击雷电产生原因及影响因素。结果发现:建筑物尖端电场畸变值是影响侧击雷电产生的重要参量,当下行先导靠近建筑物且传播位置低于建筑物的高度时,建筑侧面电场畸变值达到触发阈值,侧击雷电易产生;下行先导的初始电位以及建筑物几何特性（高度和宽度）是影响侧击雷电发生概率的重要因素,当下行先导初始电位在-9~-3 MV范围内,侧击雷电发生概率呈先增加后降低的趋势,当初始电位为-4.5 MV时,侧击雷电的发生概率达到峰值;当建筑物高度在50~150 m范围内,侧击雷电发生概率随着高度增加呈先增加后减少的趋势;当建筑物高度为100 m时,侧击雷电发生概率达到峰值;当建筑物宽度在30~70 m范围内,侧击雷电发生概率随建筑物宽度呈递减趋势;当建筑物宽度为30 m时,侧击雷电的发生概率达到峰值。     

基于空侧货物运输系统的中国民用机场可达性评价

基于机场连接的航线网络,把某机场到其他机场的年可用货运吨位加权之和作为测度指标,分析2001~2013年间中国民用机场空侧货运可达性在时间和空间上的变化。研究结果表明：机场空侧货运可达性逐年提高,机场间可达性绝对差异变大,相对差异减小;北京、上海、广州和深圳机场的空侧货运可达性排名稳居前四;机场空侧货运可达性从大到小按指数规律迅速下降;华北区机场空侧可达性最高,新疆区机场可达性最低,东西部机场可达性差距缩小;七大区域机场可达性总体呈上升趋势,但上升幅度各异。     

Diatom response to Asian monsoon variability during the Holocene in a deep lake at the southeastern margin of the Tibetan Plateau

Diatom analysis was applied to a 5.56‐m‐long sediment core, spanning the last 7.8 ka, from Lake Chenghai on the southeastern margin of the Tibetan Plateau. Diatom assemblages are dominated by Cyclotella rhomboideo‐elliptica, Cyclostephanos dubius and small fragilarioid and periphytic taxa. These diatom taxa are interpreted to be sensitive to changes in trophic status and/or turbulence of the water column that are probably related to variations in precipitation and temperature induced through the Asian monsoon. High abundances of C. dubius, Staurosirella pinnata and periphytic taxa suggest higher trophic status (mesotrophic) and stronger turbulence in the water column in the middle Holocene (7.8–4.5 ka BP). During the period of 4.5–2.3 ka BP, a decline in C. dubius, S. pinnata and periphytic taxa, and an increase in C. rhomboideo‐elliptica with the appearance of Cyclotella ocellata suggests a response to decreasing trophic level (more oligotrophic). After 2.3 ka BP, the persistent increases in C. rhomboideo‐elliptica and the loss of Cyclotella ocellata mirrored a further decrease in trophic level (oligotrophic). The main changes in the diatom assemblages in the Lake Chenghai sediment core reflect direct and indirect climate forcing and in particular, the strength of monsoonal precipitation, which in turn corresponds to orbitally induced variability in Northern Hemisphere summer solar insolation since 7.8 ka BP.     

东海陆架油气勘探的新领域

基于东海陆架区的物探、化探和钻井等方面资料分析了陆架的地层结构和构造特征。东海陆架盆地具有叠合复式盆地的特征。新生代含油气盆地之下叠置了中生代和古生代的盆地和含油气层,巨厚的前第三系地层为油气提供了丰富的物质基础。化探资料以及荧光、酸解烃和甲烷等指标表明,在诸如海礁凸起等高构造区有极好的油气异常显示,油气存在于前第三系之中。钻探证明,瓯江凹陷东侧（又称丽水凹陷）的侏罗系中有烃源岩,前古生界的变质岩中有油气显示。因此,海礁凸起、渔山凸起、瓯江凹陷东侧、长江凹陷与西湖凹陷之间以及浙闽隆褶带的前第三系是东海陆架区油气勘探的新领域。     

基于GIS技术的河源地区猕猴桃种植生态适宜性评价

利用河源及其周边地区共24个国家气象站1970-2018年气象资料和地理信息数据,通过分析河源猕猴桃主产区气候特征及影响猕猴桃生长的关键因素,选取气象、地形和土壤三大类共12个评价因子指标,在GIS技术的支持下,采用层次分析法和加权指数求和法,构建河源地区猕猴桃种植生态适宜性评价指标体系,将种植区域划分为不适宜、次适宜、适宜和最适宜4个等级,并绘制出猕猴桃种植综合区划图。分析结果表明:连平、和平、龙川北部的零散区域为猕猴桃种植最适宜区,约占总区划面积的3%;中部偏西和紫金南部的零散区域为不适宜区,约占总区划面积的2%,主要受土壤、降水和气温等因素的限制;其他区域则处于适宜和次适宜种植区。     

Assimilation of temperature and salinity using isotropic and anisotropic recursive filters in Tropic Pacific

A data assimilation scheme used in the updated Ocean three-dimensional Variational Assimilation System (OVALS),OVALS2,is described.Based on a recursive filter (RF) to estimate the background error covariance (BEC) over a predetermined scale,this new analysis system can be implemented with anisotropic and isotropic BECs.Similarities and differences of these two BEC schemes are briefly discussed and their impacts on the model simulation are also investigated.An idealized experiment demonstrates the ability of the updated analysis system to construct different BECs.Furthermore,a set of three years experiments is implemented by assimilating expendable bathythermograph (XBT) and ARGO data into a Tropical Pacific circulation model.The TAO and WOA01 data are used to validate the assimilation results.The results show that the model simulations are substantially improved by OVALS2.The inter-comparison of isotropic and anisotropic BEC shows that the corresponding temperature and salinity produced by the anisotropic BEC are almost as good as those obtained by the isotropic one.Moreover,the result of anisotropic RF is slightly closer to WOA01 and TAO than that of isotropic RF in some special area (e.g.the cold tongue area in the Tropic Pacific).     

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澳门沿海的底栖贝类

报道了澳门沿海底栖贝类56种,隶属40属27科3纲,并对主要可发展养殖的经济贝类作了介绍.     

某烟花爆竹仓库的雷电灾害风险评估

根据对田东县某烟花爆竹仓库的设计方案进行雷电灾害风险评估,在确保人员生命损失风险值满足国家有关规定的容许值的前提下,通过防雷装置成本效益估算,改进了原设计方案中经济不合理的设计。也通过雷电灾害风险评估对烟花爆竹仓库的防雷设计提出了一些建议和思考。