成矿作用中金银的共生与分离及Au/Ag比值的校正

在内生作用中金与银既有共生的一面 ,又有分离的一面。其共生与分离受地球演化历史制约 ,受控于元素化学性质和地球化学亲和性 ,与岩浆起源、演化有关 ,受控于不同的基底建造和构造单元。成矿作用中金与银的共生与分离可用Au/Ag比值大小来衡量 ,本文提出了根据Au、Ag的地壳克拉克值和工业品位对传统的Au/Ag比值进行校正的方法 ,校正后的Au/Ag比值可有助于矿床研究、找矿预测和资源评价等工作     

遥感与GIS支持下的城市绿地信息提取方法研究--以深圳市为例

城市绿地作为城市结构中的自然生产力主体，在城市系统中起着重要作用。传统的城市绿地调查多采用人工普查并结合统计学方法进行城市绿地调查，需要投入大量的人力和资金，但得到的数据精度和现时性都较差，而采用高分辨率遥感卫星数据与地理信息系统相结合的方法，可以达到对城市绿地遥感数据的快速特征提取和准确的空间统计分析。文章采用基于遥感和GIS相结合的方法，并以深圳市为例，进行了城市绿地特征提取方法的研究和应用分析。     

山一村山地生态系统结构功能和系统调控

本文对山－村山地生态系统的结构和功能、能量产投比、生物量等进行实地调查和研究。结果表明，通过多年生态建设，山地生态系统已显示较好的经济、环境和社会效益。     

荔枝花雄蕊和雌蕊发育过程中碳氮化合物的动态变化

比较分析了荔枝花性决定中碳氮化合物的动态变化。结果发现：C/N较大有利于雄蕊分化,反之则有利于雌蕊分化;氨基酸含量较高有利于雌蕊分化,雄蕊的氨基酸含量仅为雌蕊的一半。脯氨酸与花粉育性存在着密切相关关系。另外,探讨了雌蕊或雄蕊败育的生理意义,在长期的进化中,败育的雌蕊或雄蕊“废物”重新被利用,为同一花中迅速发育的雌蕊或雄蕊提供能量和物质的需求,表5参13。     

西太平洋海域海水和雨水的化学特征

本工作测定了西太平洋海域中海水、海水悬浮物和海面上雨水的元素组成和浓度。通过富集因子的计算,探讨海面上雨水中微量元素的富集程度及其来源,讨论了海面上气溶胶粒子大小与洗出因子的关系,结果表明不同质量粒径大小的微量元素在公海上具有相似的洗出因子。     

Tests for a biased sex ratio when the data are clustered

In behavioral ecology the overall sex ratio in a population of birds is often tested to see if it differs from a 50/50 ratio. In recent publications the binomial test or the ² test are carried out although the sexes of chicks within the same nest may not be independent. The lack of independence occurs since female birds can adjust the sex ratio in an adaptive way as demonstrated in recent studies. In order to take dependence into consideration the Wilcoxon signed rank test based on the within-brood differences between the proportions of sons and daughters was performed in a study investigating great tit hatchling sex ratios. We compare this test with a test based on an optimally weighted estimator recently proposed for medical studies with clustered binary data. According to our simulation results, this novel test is more powerful than the Wilcoxon signed rank test and should be used for the analysis of avian sex ratios. The methods are illustrated with real data from the great reed warbler.     

Colony level sex allocation in a polygynous and polydomous ant

The colony-level sex allocation pattern of eusocial Hymenoptera has attracted much attention in recent studies of evolutionary biology. We conducted a theoretical and empirical study on this subject using the dolichoderine ant Technomyrmex albipes. This ant is unusual in having a dispersal polymorphism in both males and females. New colonies are founded by an alate female after mating with one or more alate males in the nuptial flight. In mature colonies, the reproductive role of the foundress queen is taken over by wingless offspring (supplementary reproductives). Mature colonies are extremely polygynous, with many wingless queens reproducing through intea-colonial mating with wingless males (inbreeding), and producing both alate and wingless sexuals. The population sex ratio of wingless sexuals was found to be extremely female-biased, while the population allocation ratio of alates was almost 1:1. This result suggests that there is local mate competition among wingless sexuals. A specific model for this extraordinary life cycle predicted that the asymmetry of regression relatedness (b _f/b _m) will disappear during the first few generations of wingless reproductives after the foundress dies. If colonies begin to produce alates after several wingless generations, this undermines the hypotheses for intercolonial sex ratio variation based on the relatedness asymmetry. We compared the magnitude of variation in sex ratios and other characteristics between two levels (within-colony-inter-nest and between-colony). Although there was considerable within-colony variation in all the examined characteristics, between-colony variances were always larger. This means that allocation is important at the whole-colony level, not that of the nest. There was no apparent correlation between the sex ratio of alates and colony size. Furthermore, partial correlation analysis indicated that neither the number of workers nor investment in alates explained the variation in the sex ratio of alates. The only factor which was significantly correlated with the sex ratio of alates was the sex ratio of wingless sexuals (a positive correlation). We conclude that both the alate and wingless sex ratios may be influenced by a common primary sex ratio at the egg stage, the variance of which may have genetic components. In the wingless sexuals, partial correlation analysis indicated that colony size and the number of workers explained the sex allocation ratio. The number of wingless females was strongly (positively) correlated with the total investment in wingless sexuals, while the number of males showed no such correlation. There is, however, no convincing explanation for the variation in sex allocation ratio of wingless sexuals, because the estimates of investment in wingless males may have a large sampling error. Correspondence to: K. Tsuji     

沙打旺与柳枝稷单、混播种苗期水分利用和根冠生长的比较

在室内生长箱内盆栽沙打旺和柳枝稷的苗期生长阶段进行高土壤水分 (黄绵土土壤田间持水量FC的 80 % )和低土壤水分 (5 0 ?)处理 ,比较二者单、混播种植下水分利用与根冠生长差异 ,以探讨黄土高原半干旱丘陵区牧草植物的合理种植方式 .结果表明 :在水分利用方面 ,低水处理下混播使沙打旺和柳枝稷叶片瞬时水分利用效率均较单播提高 ,低水处理后混播群体水分利用效率也显著比单播柳枝稷增大 .在根冠生长方面 ,混播促进了柳枝稷地上部分植株高度生长 ,并使地下部分分配比重增大 ,根系绝对长度缩短 ;混播后沙打旺的植株高度降低 ,根系绝对长度增加 ,但干物质分配比重减小 .低水处理后 ,沙打旺和柳枝稷混播下的根冠生长趋向于资源的充分合理利用 ,表现在混播群体的根系生长有利于充分利用土壤深层水和表层来水 ,混播后地上部分高度的生长特征变化利于对光的利用 .因此 ,在水分和养分条件相对较差坡地占较大比例的半干旱黄土丘陵地区 ,采用沙打旺和柳枝稷混播种植相比各自单播利于促进苗期生长与提高土壤水分利用率 .图 2表 2参 10     

射流曝气的气液两相流的数值模拟

射流曝气在活性污泥处理方法中起着重要的作用。采用数值模拟的方法研究自吸式单级单喷射流器中的气液两相流动状况，通过对不同长径比和喷嘴面积比的射流曝气器模型的气液两相流的计算，定量分析长径比和喷嘴面积比对射流曝气器流场和空气与工作介质流量比的影响，为进一步设计开发新型高效的射流曝气器提供参考。