Phylogeny of subclass Scuticociliatia (Protozoa, Ciliophora) using combined data inferred from genetic, morphological, and morphogenetic evidence

Gene sequence-based genealogies of scuticociliates are different from those produced by morphological analyses. For this reason, 11 representative scuticociliates and two ambiguously related genera were chosen to test the ability of combined phylogenetic analyses using both gene sequences and morphological/morphogenetic characteristics. Analyses of both the SSrRNA gene sequences and the combined datasets revealed a consistent branching pattern. While the terminal branches and the order level relationships were generally well resolved, the family level relationships remain unresolved. However, two other trees based on ITS1-5.8S-ITS2 region sequences and morphological/morphogenetic characters showed limited information, due to a lack of informative sites in these two datasets. Our data suggest, however, that the combined analysis of morphological/morphogenetic characters and gene sequences did produce some changes to the phylogenetic estimates of this group.     

湘江沟头地表和深部地质约束的水系侵蚀能力差异及袭夺预测分析

基于地表基础地质调研、GIS流域分析与深部地球物理相结合的综合方法, 选取长江支流湘江沟头的两条具有共同溯源侵蚀点(矮塘村)的水系作为研究对象, 对比两条水系程江和注江相同河长流经区的地形地貌、水位高程、地层、构造背景以及深部电阻率数据, 综合分析两者的侵蚀能力的差异性。其中, 注江流域的基岩易于被侵蚀, 节理较为发育, 使得其下蚀作用和溯源侵蚀能力较强。预测两条水系的演化趋势会在矮塘村周边发生河流袭夺现象, 从而影响到程江下游的鲤鱼塘镇的城市居民生活用水和工农业生产。此外, 注江的持续下蚀作用会加强对基岩白垩系红层的侵蚀作用, 推测其流域未来可呈现更为壮观的丹霞地貌。      

降水时风廓线雷达风场反演效果评估

风廓线雷达（wind profile radar,WPR）因具有高时空分辨率特点,成为当前短时临近预报的重要参考工具。降水时WPR同时接收大气湍流回波和降水粒子散射回波,现有技术不能有效分离叠加在一起的湍流信号和降水信号,导致降水期间风廓线雷达反演的风场数据严重缺失或失真。根据风廓线雷达探测技术原理及降水天气的功率谱特点,提出了降水天气时风廓线雷达湍流信号提取方法（WPR-HW）,并选取2015—2018年天津10次降水过程对WPR-HW方法进行模式检验及个例效果评估。结果表明:WPR-HW方法对改善降水期间风廓线雷达风场数据缺失问题效果明显,在选取的10次降水过程中,目前通用的风廓线雷达风场反演方法（WIND）风场数据平均缺失率为25.4%,WPR-HW方法未出现风场数据缺失现象;WPR-HW方法较WIND方法反演风场数据可信度有显著提高,反演数据与再分析数据的风速均方根误差由WIND方法的2.3 m·s-1降至WPR-HW方法的1.6 m·s-1,风向均方根误差由WIND方法的45°降至WPR-HW方法的22°,从而验证WPR-HW方法在降水期间适用。