河北蕨类植物区系与其他区系关系的比较

利用丰富度指数,通过与河南、浙江等其他省区的比较分析,认为河北省蕨类植物物种贫乏．运用聚类分析和主成分分析的方法对河北省与其他7个地区蕨类植物区系所构成的区系谱进行定量比较研究,得出河北与山东的蕨类植物区系关系最为密切,与河南、安徽、江苏、浙江关系渐远,而与广西、山西的关系最远的结论．     

Seasonal abundance and life cycle of Archaeomysis articulata (Crustacea: Mysidacea) on a sandy beach of western Hokkaido,Japan

Abundance and life cycle of the sandy beach mysid Archaeomysis articulata Hanamura were investigated based on seasonal collections over 2 years in the surf-swept intertidal zone of an open sandy beach in Ishikari Bay, western Hokkaido, Japan. The number of mysids in the intertidal zone increased from winter to spring, reaching its maximum in summer to autumn (average >2500 ind. m^-2), and decreased considerably towards the end of the year. The abundance was maintained at a minimal level (<200 ind. m^-2) throughout the winter. The breeding season was March to November, during which the liberation of young was most intensive from late April to mid-October. Three alternate generations, including overwintering, spring and summer generations, were suggested from field observations. Archaeomysis articulata is primarily iteroparous; only a restricted number of breeding females could produce more than two broods. The life span was estimated to be 7–9 months for the overwintering generation and 2.5–3.5 months for the spring–summer generations. The sex ratio fluctuated at samplings, with a tendency toward female dominance (overall mean=54%). The number of embryos carried by a single female ranged from 16 to 94, tending to increase with increasing size of females. The size of egg-like embryos varied seasonally from 0.45 to 0.54mm, being largest in spring and smallest in summer, with no correlation to the length of females; water temperature is considered an important factor in regulating the size of eggs. The embryonic development time was estimated to be 1.5 months for the spring generation (water temperature 5–10°C), and much shorter than this for the summer and overwintering generations. The mortality rate during embryonic development was estimated to be 7–18%.     

Lakes’ state and abundance across the Tibetan Plateau

Understanding the changes in number and areal extent of lakes,as well as their abundance and size distribution is important for assessments of regional and global water resources,biogeochemical cycles,and changes in climate.In this study,changes in lake area greater than 1 km2are mapped using Landsat datasets,spanning the 1970s,1990,2000,and 2010.In addition,high-resolution images(GeoCover Landsat mosaic 2000,with a pixel size of 14.25 m)are used for the first time to map lakes as small as 0.001 km2across the entire Tibetan Plateau(TP).Results show that the numbers and areal extent of individual lakes[1 km2in size show a slight decrease between the 1970s and 1990,followed by a clear increase from 1990 to 2010.Ninety-nine new lakes are identified between the 1970s and 2010,71 of which are found between 1990 and 2010.This indicates the accelerated glacier melt and/or increased difference of precipitation minus evaporation since the 1990s.More than 80%of the lakes show an increase in their area between the 1970s and2010.The lake census,using 2000 imagery,shows that there are 32,843 lakes with a total area of 43,151.08±411.49 km2,which makes up 1.4%of the total area of the TP.Around 96%of all lakes are small,with an area\1 km2,while the 1,204 large lakes([1 km2)account for96%of the total lake area.The TP is subdivided into 12greater drainage basins,and of these the inner TP dominates in terms of the number of lakes(55.03%),the total area of lakes(66%),and lake density(0.026/km2compared to the mean,0.011/km2).A plot of lake abundance against size shows that the size distribution of lakes departs from a typical power-law distribution,but displays such a distribution at the mean elevation(4,715 m),with an r2value of 0.97 and a slope of-0.66.The slopes of the abundance-size equations from each of the 12 greater basins,and from all basins together,are larger than-1,supporting the inference that larger lakes,rather than the small lakes,contribute more to the total lake surface area across the TP.The lake inventory provided in this study,along with the assessment of lake size distribution,have important implications for estimates of water balance,for water resource management,and for lake area estimations in the TP.     

贫金属星的重核素丰度

利用太阳系的重核素丰度以及ｓ－过程、ｒ－过程的相对贡献,结合贫金属星重元素的观测值及星系化学演化的计算结果,计算了不同金属度贫金属星重核素丰度分布。     

莘县凹陷下第三系生油条件的探讨

根据莘县凹陷下第三系生油岩的发育特征和地球化学特征。对凹陷内下第三系生油问题进行了探讨.指出沙三中下段是本区主力生油层,其有机质的丰度和类型.可与好生油凹陷相媲美.但由于生油层埋藏较浅,地温梯度偏低,致使各生油层有机质的成熟度明显比好生油凹陷低,主要生油层目前仍处于低成熟—成熟演化阶段.主要油源区集中在禹城、梁水镇等深洼陷区,它们控制着下第三系油气最有远景地区的分布.     

石灰土元素垂向分布地化特征研究

针对高原残坡积石灰土元素的垂向变化的地化特征研究不足,缺乏垂向对比分析的问题,为研究石灰土元素垂向的地化特征、迁移聚失及丰度变化,了解土壤元素的空间分布及补偿状态,以云贵高原南部广南县南屏、珠街等地母岩为T1、P1、D2、∈3的石灰土为研究样本,实地调查、采样、检测。分析及计算出:土壤元素Si、Al、K含量为38.18%~1.54%,Ti、Mg、Ca、Mn含量为0.83%~0.042%,其他元素为0.111%~0.000 01%,ⅢⅡⅠ类型占62.5%;Qij占85.3%,Qi为86.6%,土壤Pi占68.5%。结果为:母岩风化至成土过程中元素以迁移流失为主,土壤元素相对母岩以迁移聚集为主,丰富级元素多,底层土元素淋淀较表层土高。