地理图像信息阅读能力的培养策略

地理图像是地理学的骨架,能够提供比文字描述更为丰富的地理信息,其中蕴藏着丰富的地理现象、知识、技能以及智慧,是地理学科特有的信息综合载体和教学工具。本文主要从图像信息的阅读与观察、图像信息的发现与获取、图像信息的描述与阐释三个方面来谈谈地理图像信息阅读能力的培养策略。     

酸性矿山废水中生物成因次生高铁矿物的形成及环境工程意义

酸性矿山废水(acid mine drainage,AMD)是一类pH低并含有大量有毒金属元素的废水。AMD及受其影响的环境中次生高铁矿物类型主要包括羟基硫酸高铁矿物(如黄铁矾和施威特曼石等)和一些含水氧化铁矿物(如针铁矿和水铁矿等),而且这些矿物在不同条件下会发生相转变,如施氏矿物向针铁矿或黄铁矾矿物相转化。基于酸性环境中生物成因次生矿物的形成会"自然钝化"或"清除"废水中铁和有毒金属这一现象所获得的启示,提出利用这些矿物作为环境吸附材料去除地下水中砷,不但吸附量大(如施氏矿物对As的吸附可高达120mg/g),而且可直接吸附As(III),还几乎不受地下水中其他元素影响。利用AMD环境中羟基硫酸高铁矿物形成的原理,可将其应用于AMD石灰中和主动处理系统中,构成"强化微生物氧化诱导成矿-石灰中和"的联合主动处理系统,以提高AMD处理效果和降低石灰用量。利用微生物强化氧化与次生矿物晶体不断生长的原理构筑生物渗透性反应墙(PRB)并和石灰石渗透沟渠耦联,形成新型的AMD联合被动处理系统,这将有助于大幅度增加处理系统的寿命和处理效率。此外,文中还探讨了上述生物成因矿物形成在AMD和地下水处理方面应用的优点以及今后需要继续研究的问题。     

Advances in the Research of Impact of Decadal Solar Cycle on Modern Climate

Role of solar activity on modern climate change, particularly in the decadal scale is an important scientific issue. This paper reviews the recent observation of decadal solar signal in earth’s climate, with focus on the mechanism of solar radiation, ultraviolet radiation and cosmic rays on climate system ,and its validation. The paper points out that the assessment of uncertainty in observations, amplification process of the climate system, as well as possible future impact of solar extreme events are challenges in the present study. Finally, the keys of breakthrough are pointed, to provide a reference for future research.     

Geochronology of the volcanic rocks in the Lu-Zong basin and its significance

The Lu-Zong (Lujiang-Zongyang) basin is one of the most important volcanic basins in the middle and lower reaches of the Yangtze River area, China. It comprises four shoshonitic volcanic units, which are, in an ascending order, the Longmenyuan, Zhuanqiao, Shuangmiao and Fushan Groups. The LA-ICP MS U-Pb zircon ages of the four units are: 134.8±1.8 Ma for the Longmenyuan Group, 134.1±1.6 Ma for the Zhuanqiao Group, 130.5±0.8 Ma for the Shuangmiao Group, and 127.1±1.2 Ma for the Fushan Group. The results indicate that all volcanic rocks in the Lu-Zong basin were formed in the Early Cretaceous from about 135 Ma to 127 Ma, lasting 8-10 Ma. There were no Jurassic volcanic activities in all the volcanic basins including the Lu-Zong basin in the middle and lower reaches of the Yangtze River area. This work has provided new chronological results for the further study and understanding of the tec- tonic, magmatic and metallogenic processes of eastern China in the Mesozoic.     

寿昌—临浦火山岩带赋矿流纹岩特征及归属雏议

本文介绍的火山岩带,有层状流纹岩及穹丘状、岩颈状等非层状流纹岩,分别属溢流相、侵出相及火山管道相,三种流纹岩均受火山岩带核中断裂及晚期火山构造控制,复盖或穿发寿昌组一段地层,又被寿昌组一段之后的次火山岩及隐爆岩所穿切,局部被横山组不整合复盖。该类流纺岩同位素年龄值较小,多数在１３０Ｍａ左右,处于晚侏罗世与早白垩世过渡期。根据其层序、穿切关系及同位素年龄等,认为三种流纹岩均属火山岩带晚期不同岩相的产     

区域水资源协调分析

本文建立了区域水资源协调分析的概念模型和通用多区域-多目标数学模型(MAOM),并结合新疆昌吉州的具体情况,运用目标规划法进行求解,确定了昌吉州近期和远景的水资源合理利用结构。     

An explanation of the dimensions of penumbral filaments

Unstable pertubation modes exist in the magnetic field of penumbral electric current and I think the penumbral filaments are formed from the development of such modes. Under the short wave approximation the non-adiabatic dispersion equation is solved in the radial and transverse directions of the sunspot. From the condition of instability the length and width of the penumbral filament can be evaluated and it is found that the filament mode is static in the direction of the length and is non-moving in the direction of the width, that the penumbral filaments are a feature of the sunspot magnetic flow under gravity and that the presence of the filaments implies the existence of a twisted magnetic field.     

Behaviour of an outward inclined-vertical framed retaining wall of an excavation

Acta Geotechnica - A new excavation retaining structure, referred to as an outward inclined-vertical framed retaining wall (OIVFRW), has been developed and adopted in practice. This retaining...     

A mechanism for the origin and development of the large-scale dunefield on the right flank of the lower reach of Laoha River, Northeast China

By viewing satellite imagery, a striking large-scale dunefield can be clearly perceived, with a size of nearly 63 km long and 11 km wide, and trending NE–SW, on the right flank of the lower Laoha River, Northeast China. By means of remote sensing imagery analysis and field observation as well as a comparison with a small-scale dunefield on the right flank of the lower Xiangshui River, analogous to the case of the lower Laoha River, this paper presents a new mechanism for its origin and development. The results show that:(1) the large-scale dunefield bears a tile-style framework overwhelmingly composed of transverse barchanoid ridges perpendicular to the predominant winds, and inlaid diverse blowouts.(2) The small-scale dunefield, referred to as a primary structural unit of the large one, is typical of an incipient dunefield, following the same rules of evolution as the larger.(3) A succession of barchanoid ridge chains can steadily migrate downwind in much the same manner as surface wave propagation in air or water stimulated by an incised valley, and ultimately tend to bear roughly the same wavelength and amplitude under stable climate and hydrologic regimes.(4) The first ridge chain acquires its sand source substantially from the downwind escarpments exposing the loose Quaternary sandy sediments to the air, while the ensuing ridges derive their sands dominantly from in situ deflation of the underlain Quaternary loose sandy sediments in blowouts, partly from the upwind ridges through northern elongated horns. Theoretically, the sands from riparian escarpments can be transported by wind to the downwind distal end of a dunefield after sufficient long duration.(5) The lower Laohahe region experienced probably three significant climatic changes in the past, corresponding to the three active dune belts, suggesting that once a large-scale dunefield occurs, it is nearly impossible to be completely stabilized, at least in its central portions. At present, seasonal shrinkage and stagnation of the lower Laoha River, widespread farming and afforestation in the valley, and establishing windbreaks downwind of the valley as well as surrounding the dunefield, appear to have significantly modified local flow fields and sand sources, engendering significant degradation of the dunefield.