Using the optical and radar satellite images for the analysis of ecological conditions in the marine environment

Considered are the possibilities for detecting the zones of ecological problems of marine environment using the ocean color sensors data and the radar images. Presented are the peculiarities of satellite data interpretation and the experimental results indicating the spatial and temporal distribution of biogenic slicks and chlorophyll-a concentration as the indicators of ecological conditions in the marine environment. Proposed is the multiparameter correlation graph displaying the relationship between the ecological factors significant for studying the anthropogenic eutrophication.     

Environmental impact assessment on water quality deterioration caused by the decreased Ganges outflow and saline water intrusion in south-western Bangladesh

 This paper deals with an environmental impact assessment of low water flow in the river Ganges during a dry period at the Khulna and Mongla port areas in south-western Bangladesh. Large-scale surface water withdrawal in India after commissioning the Farakka Barrage causes a drastic fall in the Ganges low-flow condition within the Bangladesh territory during every dry period. The average lowest discharge in the Ganges is 552 m³/s, which is about 73% less than that in the pre-Farakka time. This has caused the deterioration of both surface and groundwater quality of the study area. Salinity is the principal cause of water quality degradation in the area. Present observation shows that the surface water of the area is sulphate-chloride dominated, which signifies high salinity whereas the groundwater is categorized as of medium to high salinity. To maintain the Rupsa River's maximum salinity below 1000 μS/cm the discharge in the Ganges should be ∼1500 m³/s, whereas that at Garai basin is ∼10 m³/s. If this present situation continues it will be a crippling blow to the environment of the area in the long term. An integrated multidisciplinary approach to hydrogeological research is urgently required to salvage the area from further deterioration. Received: 9 August 1999 · Accepted: 8 March 2000     

Three-dimensional tomographic inversion of the seismic velocity structure of the crust and upper mantle of northwestern Nicaragua

Journal of Seismology - A three-dimensional tomographic image of the seismic velocity structure in the crust and upper mantle of northwestern Nicaragua was performed using the back-projection...     

福建上杭铜矿沟—萝卜岭斑岩型铜矿床地质特征及远景评价

上杭县铜矿沟和萝卜岭矿段组成一个斑岩型铜矿床．萝卜岭矿段位于花岗闪长斑岩北东端的前峰部位，铜矿沟则是其往南西深部的延伸，通过对铜矿沟—箩卜岭斑岩型铜矿床地质特征的研究，认为铜矿沟斑岩型铜矿埋藏总体较浅、品位较低、厚度稳定且较厚，对于指导该区寻找浅部斑岩型铜矿具有重要的意义。     

Prediction of surface horizontal displacements, and gravity and tilt changes caused by filling the Three Gorges Reservoir

 Horizontal displacements, and gravity and tilt changes induced by filling the Three Gorges Reservoir are modeled using elastic loading Green functions. When the water surface reaches its highest level, the effects become maximum on the reservoir banks. The longitudinal and latitudinal components of the horizontal displacements reach −8.2 and 7.7 mm respectively, gravity is increased by up to 3.4 mGal, and the prime vertical and meridian components of the tilt changes are −7.8 and −17.5 arcseconds respectively. Accordingly, the filling of the reservoir will influence values observed from global positioning system (GPS), gravimetry and tilt measurements in the area. The results given can be used to provide important corrections for extracting earthquake-related signals from observed data. Received: 19 January 2001 / Accepted: 3 September 2001     

黄河流域水循环研究的进展和展望

总结了黄河流域水循环研究的进展,指出缺乏立足于水循环整体的机理过程的探讨及缺乏较成熟的流域水文模型是已有研究的不足。为能更好地模拟水文过程对各种作用力的响应,今后研究的方向将是建立既考虑垂向水分和能量传输(如降水,蒸发,感热),又考虑水平向的地表水分运动(汇流)和地下水基流过程的黄河流域的分布式水文模型。模型将结合遥感信息与地面资料,建立与区域大气环流模式(GCM)的接口,辅之以野外生态试验小区、径流试验场和室内试验的资料,以深入探索黄河流域水循环动力学机制     

中更新世以来西菲律宾海上层水体结构演化特征——来自钙质超微化石Florisphaeraprofunda的证据

MD06-3050岩芯位于西菲律宾海吕宋岛以东本哈姆高原,利用钙质超微化石下透光带种属Florisphaera profunda占总颗石的相对丰度,恢复了中更新世以来该海区的上层水体结构演化特征。结果显示,西菲律宾海区自1040ka以来,温跃层/营养跃层经历了由浅—深—浅—深的长周期变动,可能是由于全球碳库的长周期变化对气候系统的大规模调整所致; 同时温跃层/营养跃层也具有明显的冰期-间冰期旋回性特征。温跃层变动的另一个重要特征是在中布容事件前后呈现出相反的冰期-间冰期变化趋势,认为可能是由东亚冬、夏季风强度变化引起。     

Present-day Horizontal Mobility in the Serbian Part of the Pannonian Basin; Inferences from the Geometric Analysis of Deformations

In tectonically complex environments, such as the Pannonian Basin surrounded by the Alps–Dinarides and Carpathians orogens, monitoring of recent deformations represents very challenging matter. Efficient quantification of active continental deformations demands the use of a multidisciplinary approach, including neotectonic, seismotectonic and geodetic methods. The present-day tectonic mobility in the Pannonian Basin is predominantly controlled by the northward movement of the Adria micro-plate, which has produced compressional stresses that were party accommodated by the Alps-Dinarides thrust belt and partly transferred towards its hinterland. Influence of thus induced stresses on the recent strain field, deformations and tectonic mobility in the southern segment of the Pannonian Basin has been investigated using GPS measurements of the horizontal mobility in the Vojvodina area (northern Serbia).     

Electromagnetic inertio-gravity waves in the Earth's ionosphere

Propagation of electromagnetic inertio-gravity (IG) waves in the partially ionized ionospheric E- and F-layers is considered in the shallow water approximation. Accounting of the field-aligned current is the main novelty of the investigation. Existence of two new eigen-frequencies for fast and slow electromagnetic waves is revealed in the ionospheric E-layer. It is shown that in F-layer slowly damping new type of inertial-fast magnetosonic waves can propagate. Slowly damping low-frequency oscillations connected with the field-aligned conductivity are found. Broad spectrum of oscillations is investigated.