GRADIENT DISTRIBUTION OF ACID RAIN IN THE SCENIC RESORT OF THE BAIYUN MOUNTAIN IN GUANGZHOU

1 INTRODUCTION Sitting in the central part of the Pearl River Delta, Guangzhou is one of the cities in China that are most polluted by acid rain. Broad attention has been brought to the problem. Since the early 1980s, a series of observation and studies h…     

新疆及边邻地区7级以上地震前后北天山地下流体动态的异常变化

重点分析了新疆及边邻地区1980年以来6次7级以上地震前后北天山地下流体动态异常资料，其中3次地震前地下水有短期前兆异常变化，震时同震地震波效应普遍存在，震后异常十分突出且幅度大；以水位为主的水动力学效应反映了大区域应力调整过程具有不可逆特征。水文地球化学参数的变化不敏感。讨论了地下水远程效应与井震距离的关系以及阶跃异常的幅度等问题。     

金沙江下游白鹤滩水电站岩体结构的建造特征

拟建的白鹤滩水电站的坝基为峨眉山玄武岩。峨眉山玄武岩由火山熔岩类、火山碎屑熔岩类、火山碎屑岩类和沉积火山碎屑岩类所组成。火山熔岩又可划分为斜斑玄武岩、块状玄武岩和杏仁状玄武岩;火山碎屑岩包括集块岩、火山角砾岩以及凝灰岩;而沉积火山碎屑岩类则由沉火山角砾岩和沉凝灰岩所组成。不同类型岩石的结构构造、矿物成分和形成环境不同,导致它们的岩石力学性质和工程性能也不相同。块状玄武岩、斜斑玄武岩和沉积火山碎屑熔岩的抗压强度和抗风化能力都比较大,因而具有很好的工程地质稳定性;杏仁状玄武岩、火山碎屑熔岩的抗压强度稍低,但抗风化能力很好,因此也具有较好的工程地质稳定性;而火山碎屑岩包括火山角砾岩、凝灰岩的抗压强度和抗风化能力都很低,往往形成岩体中的软弱夹层,工程地质稳定性较差。     

大坂山隧道地下水动态分析及对隧道作用评估

Base on the groundwater yield, water temperature and hydrochemistry change of the groundwater, we can analyze that the summer water content is obviously greater than winter water content where the in and-out wall rock of the Daban Mountain tunnel. The groundwater supply has the extensity and the seasonality. The groundwater content of the middle tunnel wall rock changes relatively steady, mainly supply through horizontal direction. And the total groundwater content is relatively little and steady in winter. The water pressure of the wall rock cranny is little. It has the fluent drainage system to dredge groundwater, which cannot constitute a threat to the tunnel lining. And the cold-proof sluice hole can normally work to drain water.     

内蒙古"宝音图隆起"的归属讨论

对比研究表明，内蒙古“宝音图隆起”和狼山地区的古元古代宝音图岩群与新太古代色尔腾山岩群都是由中低级变质的各种片岩、大理岩组成，一致的岩石组合和变质相暗示二者可能是等同物而不是两个岩群。以物探资料为据的构造研究也证实，“宝音图隆起”与狼山地区之间并无槽一台级的大型断裂构造分开，二者实为统一的构造整体而不是分属槽台，只因两侧被两条近于平行的NE向断裂围限，使其总构造线方向呈NE或NNE向而与色尔腾山的构造线不同。结论认为，“宝音图隆起”仍是华北陆块的一部分，不属于内蒙古一大兴安蛉地槽褶皱系。     

Channel geometry of mountain streams in New Zealand

A dataset of 21 study reaches in the Porter and Kowai rivers (eastern side of the South Island), and 13 study reaches in Camp Creek and adjacent catchments (western side of the South Island) was used to examine downstream hydraulic geometry of mountain streams in New Zealand. Streams in the eastern and western regions both exhibit well-developed downstream hydraulic geometry, as indicated by strong correlations between channel top width, bankfull depth, mean velocity, and bankfull discharge. Exponents for the hydraulic geometry relations are similar to average values for rivers worldwide. Factors such as colluvial sediment input to the channels, colluvial processes along the channels, tectonic uplift, and discontinuous bedrock exposure along the channels might be expected to complicate adjustment of channel geometry to downstream increases in discharge. The presence of well-developed downstream hydraulic geometry relations despite these complicating factors is interpreted to indicate that the ratio of hydraulic driving forces to substrate resisting forces is sufficiently large to permit channel adjustment to relatively frequent discharges.     

Analysis of village accessibility and its impact on land use dynamics in a mountainous province of northern Vietnam

Surveys carried out in mountainous areas of northern Vietnam at research sites selected across a gradient of market integration, revealed strong relationships between the location of the village with respect to the national road network and the nature of its land-use systems, its poverty level and more generally its potential for development. We developed and tested in Bac Kan province a method to give an objective and quantitative definition of accessibility over a large geographic area. Accessibility maps integrated in a provincial GIS showed that despite recent improvements to the road network, some remote areas do not benefit from recent development.     

贵州喀斯特山区墓地利用管理与耕地保护

通过对贵州亮岩峰丛山地的墓地进行随机抽样调查和统计分析,显示出墓地在一定坡度上的特定地段有集中趋势;在对墓地选址与土层厚度进行显著性检验后表明:喀斯特地区土层厚度著性影响墓地分布。以至于绝大多数墓地集中分布在日照较好、排水畅通、土层较厚的阳坡山麓地带,以占用土层较厚的优质耕地为主。在现实的墓地利用管理实践中,实施统一规划、集中管理,建立有偿使用制度、严格用地指标,加强墓地绿化,实行墓地园林化建设等措施,以期综合性多元化开发利用墓地,有效保护耕地资源。     

Spatial and temporal variability of stable isotopes (δ18O and δ2H) in surface waters of arid,mountainous Central Asia

Characterization of spatial and temporal variability of stable isotopes (δ¹⁸O and δ²H) of surface waters is essential to interpret hydrological processes and establish modern isotope–elevation gradients across mountainous terrains. Here, we present stable isotope data for river waters across Kyrgyzstan. River water isotopes exhibit substantial spatial heterogeneity among different watersheds in Kyrgyzstan. Higher river water isotope values were found mainly in the Issyk‐Kul Lake watershed, whereas waters in the Son‐Kul Lake watershed display lower values. Results show a close δ¹⁸O–δ²H relation between river water and the local meteoric water line, implying that river water experiences little evaporative enrichment. River water from the high‐elevation regions (e.g., Naryn and Son‐Kul Lake watershed) had the most negative isotope values, implying that river water is dominated by snowmelt. Higher deuterium excess (average d = 13.9‰) in river water probably represents the isotopic signature of combined contributions from direct precipitation and glacier melt in stream discharge across Kyrgyzstan. A significant relationship between river water δ¹⁸O and elevation was observed with a vertical lapse rate of 0.13‰/100 m. These findings provide crucial information about hydrological processes across Kyrgyzstan and contribute to a better understanding of the paleoclimate/elevation reconstruction of this region.