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991.
A detailed hydrogeological zoning of the central part of the Minusinsk artesian basin is performed. Local basins confined to smaller plicated structures, as well as hydrogeological massifs of local scale, are recognized within large block structures. Direction of subsurface streams and their role in the formation of groundwater resources and composition are discussed. Forecast resources of fresh groundwater are estimated for every recognized structure.  相似文献   
992.
Shchur  L. A.  Bazhina  L. V.  Volkova  N. I.  Trofimova  M. A. 《Water Resources》2003,30(1):72-80
Environmental and sanitary estimation of small-river water quality is made in the zone of influence of gold-mining facilities in Krasnoyarsk Region. The estimates are based on data on the hydrochemical regime and the characteristics of phytoplankton, microphyto-periphyton, macrozoobenthos, and ichthyofauna collected during the vegetation period of 2000.  相似文献   
993.
A mathematical model of the seashore dynamics is considered. The model describes the seashore protection against destruction by alongshore through structures, underwater trenches, and artificial islands. The results of model calculations are presented and correlated with the data of measurements made on hydraulic models.  相似文献   
994.
Synthesis of regime observations of groundwater quality at deposits under operation and thermodynamic modeling of the geochemical interaction processes that govern the groundwater chemistry were used to recognize the geochemical causes and processes that bring about an increase in the groundwater fluorine content during water withdrawal accompanied by groundwater level drop and partial drying of the aquifer. The causes of the invalidity of previous forecasts are established.  相似文献   
995.
Zemlyanaya  N. V.  Lyakhov  V. N. 《Water Resources》2003,30(4):445-452
Random walk approach is used to develop a model for long-term prediction of water quality in shallow marine waters. The model allows one to simulate variations in hydrological situations, reactive solutes, interaction between solutes and liquid and solid boundaries. The model application is illustrated by calculations for Amur Bay. Calculations using the long-term prediction model has not found a stationary state in the pollution level. The velocities of seaward motion of pollution front and the rates of increase in the concentration of a nonreactive solute are given.  相似文献   
996.
--The mechanical and statistical characteristics of acoustic emission (AE) events during stable sliding are investigated through a laboratory experiment using a granite specimen with a pre-cut fault. Numerous AE events are found to be generated on the pre-cut fault, indicating that microscopically unstable fracture occurs during macroscopically stable sliding. The composite focal mechanism solution of AE events is determined from the first motion directions of P-waves. The determined mechanism is consistent with the double-couple one expected for the slip on the pre-cut fault. The source radii of large AE events are estimated to be about 10 mm from the widths of the first P-wave pulses. These indicate that the AE events are generated by shear fracture whose faulting area is a part of the pre-cut fault plane. The occurrence of AE events as a stochastic process approximately obeys the Poisson process, if the effect of mutually dependent events consti tuting clusters is corrected. The observed amplitude-frequency relation of AE events approximately follows a power law for a limited amplitude range. As the macroscopic sliding rate increases, the number of AE events per unit sliding distance decreases. This rate dependence of the AE activity is qualitatively consistent with the observation that the real area of contact between sliding surfaces decreases with an increase in the sliding rate as reported in the literature.  相似文献   
997.
Bezverbnaya  I. P.  Dimitrieva  G. Yu.  Tazaki  K.  Vatanabe  H. 《Water Resources》2003,30(2):199-208
The response of marine microorganism community to variations in the concentrations of heavy metals in the environment is investigated for the coastal waters of Peter the Great Bay and the northern part of Primor'e. The fact of the existence and sensitivity of the individual response of plankton community microorganisms to variations in the concentrations of metals in the water under the conditions of water contamination with a complex of metals are confirmed on the basis of microbiological data and the results of their comparison to the data of chemical analysis. Microbial indication is shown to serve as an operative method of monitoring and short-term forecasting of changes in the environmental conditions of sea coastal waters. This method allows obtaining preliminary information at the stage of selecting environmental quality observation stations.  相似文献   
998.
Dzyuban  A. N. 《Water Resources》2003,30(4):413-421
The rates of microbiological processes in CH4 cycling and organic matter destruction in the bottom sediment and water of different types of lakes in the Upper Volga basin and Baltic countries are determined. The rates of CH4 removal from silts and the peculiarities of its distribution in water mass as a function of the lake productivity and the character of water mixing in it are studied. The role of processes in CH4 cycling in destruction is shown to increase with increasing lake productivity.  相似文献   
999.
1000.
A zoobenthos submodel is included in an ecosystem model. The new model is used to assess the role of zoobenthos in the phosphorus exchange at the water–bed interface, in particular, the phosphorus cycle in the water body ecosystem is described more accurately. The calculated zoobenthos distribution over the bed of a lake can be used in modeling the lake ichthyocenoses.  相似文献   
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