论水土保持与金沙江农业综合开发：以云南省为例

金沙江流域光、热、土地等自然资源丰富，已经引起各方面的关注，正在进行农业综合开发。由于特殊的地质构造和特定的自然地理环境，其开发必须搞好水土保持。水土保持是金沙江农业综合开发的基础和环境保护的重要内容，水土保持型生态农业是金沙江农业综合开发的道路。     

引滦工程对滦河三角洲盐水入侵及土壤盐渍化的影响

引滦工程后滦河三角洲水文过程发生很大变化,滦河入海水量骤减河海动力平衡破坏,海洋作用相对增强,滦河口盐度增加,盐水入侵长度增大,三角洲地下水含盐量增高,土壤盐渍化的面积扩大。     

GENETIC ANALYSIS OF ANOMALOUS VARIATION OF WATER TABLE IN CHANGPING WELL, BEIJING

Field investigation on hydrogeological environment around Changping well reveals that the anomalous uprise of 'water table begining from Oct. 1988 was mainly caused by the leakage of water from the channel leading to Shisanling Reservoir, but not the precursor of Datong-Yanggao earthquake in Shanxi Province in 1989     

外力扰动加剧与澜沧—耿马大地震的爆发

构造运动强烈、不断发生强震的云南地壳,可能经常有部分区域处于不稳定状态,外力也正是在此基础上才得以对地震活动显示出明显的调制效应。1988年11月6日澜沧—耿马7.6级、7.2级大地震前的大量观测资料表明,云南地区,特别是澜沧—耿马附近地区又再次出现了类似1970年通海7.7级、1974年大关7.1级和1976年龙陵7.4级大地震之前,曾发生过的那种地表涝旱剧变和大气压力巨涨落现象。这种震前的外部异常扰动具有很强的重复性,在对应地震上也显示了很强的应验性,故其很有可能在云南未来7级大地震的监视预报中发挥作用。     

浅海水下地形地貌遥感信息提取与应用

本文根据笔者在我国渤海海峡、闽江口、瓯江口以及珠江口附近海域的遥感实验,讨论由卫星遥感提供的水下地形地貌信息的特征、机理,提出使用信息论和灰色系统论方法分析水深遥感信息传递的过程。以此为依据,建立水深信息提取模型,研究其实用性、精度和效果。实践表明,水深遥感的测量精度没有达到大、中比例尺常规测量的要求。但作为大面积、短周期的宏观分析,特别是遥感图像上显示的海水表层流场特征,对判别浅海水下地形走向和地貌单元,了解其冲刷、沉积作用的动力因素,动态变化等具有十分重要的意义,它成为常规方法的补充手段。对近海的规划、开发,如港湾海水养殖、航道选址、海上工程、海水排污等方面的海水环境分析与宏观评价及监测,具有一定的优势。本文着重讨论了以下三个问题: 1.水下地形地貌遥感的原理与信息特性;2.水深信息提取及灰色系统方法与模糊判别模型分析;3.遥感水下地形地貌的应用与效果分析。     

The Residual Deformation and Equivalent Source of the Lancang-Gengma Earthquake

In this paper,the equivalent force inside the source which produces a large area deformation field is calculated by using the records of residual deformation,S wave radiation of shear dislocation source and Green function of the Lancang-Gengma earthquake.Under the action of equivalent force whose intensity was 1.103×1013 N,the crust derm of northeast segment of seismic fault had finished the upraise and formed permanent irrecoverable deformation within 20.46 min after the major earthquake occurred.The authors indicate that the residual deformation would split into 2 deformation fields with different propagation velocities and different directions in the Song-distance propagation process.     

Atmospheric sulfur deposition and streamwater quality in Finland

The correlation between sulfate concentrations in Finnish headwater streams and atmospheric sulfate deposition has been studied by using data from the streamwater chemistry in August–September 1990 and computed S deposition from the anthropogenic emissions. The sulfate concentrations and acidity in water are interpolated and smoothed into a deposition model grid. These data are compared with geological and pedogeochemical (glacial till) background information. The areas where the streamwater SO₄ concentrations are mainly controlled by either anthropogenic S deposition or sulfur in till is estimated by applying the fuzzy Gustafsson-Kessel algorithm, which provides a soft clustering suitable for overlapping control factors. Residual areas can be well explained by the SO₄-rich Littorina clay deposits. The higher overall background SO₄ concentrations in streams in south Finland compared with central and northern Finland are an indisputable consequence of the heavier S deposition load in the south. However, anthropogenic sulfur deposition has a clear correlation with the sulfates in streamwaters only in northeastern Lapland impacted by the large industrial emissions in the Kola Peninsula. The secondary sulfide and sulfate minerals of marine Littorina sediments are dominating sources in the broad coastal belts, as are the primary sulfide minerals locally in the Pori-Vammala area, at the eastern end of the main sulfide ore belt between Lake Ladoga and the Gulf of Bothnia, in the Outokumpu area, and in the Peräpohja and central Lapland schist belts. Consequently, in addition to the anthropogenic deposition, there are natural sources of sulfur which cause acidity of streamwaters.     

Nonmarine Cretaceous palynology of northern Kordofan,Sudan, with notes on fossil Salviniales (water ferns)

A palynological investigation of 164 samples from 18 water wells in northern Kordofan, Sudan, enabled the recognition of five informal zones based on pollen and spore assemblages ranging in age from Albian to Maastrichtian. The youngest (late Campanian-Maastrichtian) assemblages are restricted to the Bagbag Basin, whereas Albian-Cenomanian (to Turonian) sediments are widespread to the east and west of the Bagbag area. Impressions of Salvinia floating leaves from outcrops of the upper Hamrat el Wuz Formation, western part of the study area, are among the oldest occurrences of this water fern and indicate a Campanian-Maastrichtian age for these sediments.The vertical distribution of hygrophilous (pteridophytic spores) versus xerophilous (ephedroids and possibly small, weakly sculptured tricolporates) elements in the palynofloras suggests widespread moist or even aquatic habitats in the Albian-Cenomanian and Campanian-Maastrichtian. A shift towards drier conditions occurred in the late Cenomanian-Turonian. Throughout the Cretaceous, however, there may have been extensive arid/semiarid areas of non-deposition and seasonally dry periods. Some characteristics of the local palynofloras are attributed to its inner continental position. Rare Albian-Cenomanian and Campanian-Maastrichtian dinoflagellates could be interpreted as lacustrine phytoplankton rather than as evidence for marine influence.     

裂纹端部的力学研究

本文计算并讨论了忽视旋转的传统理论所不能给出的裂纹端部场与场源的相互作用，首先利用弹性力学方法计算了共线裂纹组端部的应力场及位移场，然后应用旋转理论给出共线裂纹组端部的扭转力通解，对单裂纹和双裂纹情形做了重点讨论．