共查询到20条相似文献，搜索用时 942 毫秒
1.
M. V. Mikhailova 《Water Resources》2010,37(2):160-171
The peculiarities of the hydrological regime of the Orinoco River and the coastal zone of the Atlantic Ocean that affect the
hydrological-morphological processes in the mouth area of the Orinoco River are considered. The major features of the delta
water regime, including its inundation, runoff distribution over the delta branches, water and sediment balance, and the processes
of river and sea water mixing are described. Special attention is paid to the morphological processes at the Orinoco mouth
(delta evolution and modern processes at its coastline). 相似文献
2.
Specific features of the hydrological regime of the Rhône River and the nearshore zone of its mouth are discussed. The processes of seawater intrusion into the delta branches are described. The information on the history of the delta evolution and development is presented along with the reconstruction of the Holocene evolution of the Rhône Delta and analysis of formation peculiarities of the present-day delta. Channel processes in the Rhône Delta and the dynamics of the delta coastline are described; characteristics of the deep-water fan are discussed, and the data on sediment balance are given. 相似文献
3.
The main features of hydrological processes taking place in the mouth area of the Hong Ha River in Vietnam are considered.
The geographic and hydrological conditions in the Hong Ha River basin and in its receiving water body—the Gulf of Tonkin,
South China Sea—are briefly characterized. The main features of the mouth area of the Hong Ha River as a specific geographic
object are identified. The hydrological regime of the delta and the nearshore zone of the Hong Ha River are described in detail.
Water balance of the delta, runoff water levels and delta inundation, water and sediment runoff distributions over delta branches,
and the effect of tides, typhoons, and storm surges on delta regime are considered. Present-day problems of the use and protection
of natural resources at the Hong Ha River mouth are briefly discussed. 相似文献
4.
The basic peculiarities of the hydrological regime of one of the largest mouth areas of the world, i.e., the common mouth of the rivers of Ganges and Brahmaputra, are discussed. The main features of natural conditions (including climatic) of the mouth of these rivers and the delta drainage system are characterized. The hydrological regime of the Ganges and Brahmaputra rivers, the largest rivers of South Asia, is studied in greater detail; the quantitative assessments of the water and sediment runoff of these rivers are specified. Provision is made for revealing the basic peculiarities of river flow distribution among numerous delta branches, annual floods during southwest monsoons, tidal phenomena in the maritime zone of the delta, and disastrous storm surges and inundations in the period of tropical cyclones. Flood control measures taken in Bangladesh to protect the population and lands are described. 相似文献
5.
The geographical and hydrological features of the Mekong River basin and the nearshore zone of the South China Sea, which
influence the hydrological regime of the Mekong River mouth, are discussed. Detailed characteristics are provided for the
drainage system of the Mekong River mouth area, water flow distribution among the delta branches, processes of the delta submergence
during floods, as well as propagation of tidal, surge-induced level fluctuations and seawater intrusion into the river. Regularities
of the Holocene evolution of the Mekong River mouth area and recent processes of delta formation are also discussed. 相似文献
6.
V. N. Mikhailov 《Water Resources》2011,38(6):720-734
The major hydrological and geographic characteristics of the Godavari River and the coastal zone of the Bay of Bengal that have their effect on the hydrological regime and the morphological structure of the river delta are considered. The hydrographic, climatic, and environmental conditions in the Godavari delta are described. The specific features of hydrological processes in the delta are considered, including river and bay water mixing and the impact of tropic storms and hurricanes on the delta. The main features of morphological processes in the delta are revealed, including cyclic changes in the delta in Holocene and the dynamics of the channel network and delta coastline in the past 150 years. It is shown that the processes of erosion and retreat of the delta coastline became more active in the late XX century. 相似文献
7.
Hydrological and morphological processes in the Zhujiang River (Pearl River) mouth area of China are discussed. The hydrological regime of the Xijiang River, which is the largest river of South China and the main source of water inflow into the Zhujiang mouth area, is described. The basic features of the hydrological regime of the delta and the near-shore zone of the Zhujiang River mouth are characterized, much attention being given to the role of tides and mixing of river and sea water in the hydrological regime. Special emphasis is placed on morphodynamic processes at the mouth area and the history of the Zhujiang Delta evolution. 相似文献
8.
《Continental Shelf Research》2007,27(3-4):431-451
The sediment-transport mechanisms that contribute to and redistribute the modern sediment deposits on the western Adriatic continental shelf were evaluated utilizing data collected from two instrumented benthic tripods deployed at 12-m water depth, one in the northern Adriatic basin on the Po River subaqueous delta, and the other in the central Adriatic basin on the Pescara River shelf. Sediment-resuspension events driven by cold, northeasterly Bora winds dominate the along-shelf transport climatology at both tripod locations, but at the Po delta site, the southwesterly Scirocco wind events also play a significant role. At the Pescara shelf site, interaction between Bora wind-driven currents and the Western Adriatic Coastal Current strongly contributes to the resuspension and advection of suspended sediment. Interannual variability of the forcing mechanisms (including strength, frequency, and relative mix of Bora and Scirocco wind events) is evident in the three winters of data collected on the Po River subaqueous delta. In both types of wind events, and throughout all years of data collection, the net along-shelf sediment transport is significantly larger than the net across-shelf transport at the 12-m sites. This may be characteristic of low-energy environments, where sediment resuspension and transport occurs in such shallow water that it is not subjected to strong downwelling features characteristic of higher-energy environments. 相似文献
9.
《水文科学杂志》2013,58(6):1007-1012
Abstract The effects of human activities on flood propagation, during the period 1878–2005, in a 190-km reach of the middle—lower portion of the River Po (Northern Italy) are investigated. A series of topographical, hydrological and inundation data were collected for the 1878 River Po geometry and the June 1879 flood event, characterised by an inundated area of 432 km2. The aim of the study is two-fold: (1) to show the applicability of flood inundation models in reconstructing historical inundation events, and (2) to assess the effects of human activities during the last century on flood propagation in the middle—lower portion of the River Po. Numerical simulations were performed by coupling a two-dimensional finite element code, TELEMAC-2D, with a one-dimensional finite difference code, HEC-RAS. 相似文献
10.
《Continental Shelf Research》2007,27(3-4):359-374
In this paper, we discuss what controls the occurrences of shallow gas off the Western Adriatic coast. This region of the Western Adriatic, including the Po delta and the late-Holocene mud wedge, was sampled with the R/V Seward Johnson II within the framework of the EuroSTRATAFORM project. As a part of the program, we were evaluating the causes of anomalous sub-surface and seafloor features, and specifically, quantifying shallow gas and identifying its impact on geophysical properties. The highest gas concentration off the Po delta region yielded 4.1×104 ppm, where as offshore Tronto River, the highest methane value was 7.9×104 ppm. Headspace gas analyses match well with acoustic anomalies along the Western Adriatic coast. Shallow biogenic gas off the Po delta (NW Adriatic) is spatially correlated with organic matter deposition driven by rapid and thick flood deposition. In contrast to the Po Delta, where sub-surface gas is associated with the flood deposition of organic matter, shallow gas along the Central Adriatic occurs deeper in cores, and appears to be related to methanogenesis of organic matter present in deeper deposits. 相似文献
11.
The geographic characteristics of the Nemunas (Neman) River basin is presented with due consideration for the hydrological regime of this river and the Curonian Lagoon (Marios). The following geographic and hydrographic features of the Nemunas mouth area are described in detail: the landscape and climatic conditions, delta water balance, water flow distribution among branches, flow-induced changes in water levels, specific features of ice regime in the delta, storm surges, and floods. 相似文献
12.
Water Resources - The article describes the Ili River hydrological regime, provides an insight into multiyear and intra-annual changes in the discharge in the Ili delta head, given natural water... 相似文献
13.
The Niger River delta, one of the largest deltas of the world, is characterized in this article. The geographic features, including the delta hydrographic system, natural and territorial complexes, hydrological regime, and the dynamics of the coastline, are discussed. Special emphasis is given to the assessment of the impact of the following factors on the delta structure and regime: river flow regulation, tides, the ocean level rise, sea waves, natural and human-induced land subsidence. 相似文献
14.
The hydrological regime, morphological structure, and landscapes of the Indus River delta are considered, and the significant changes that took place in them during the second half of the XX century because of the large-scale hydraulic engineering activity in the river’s basin, runoff regulation, and water withdrawal for irrigation are analyzed. It is shown that the abrupt decrease in water and sediment runoff in the Indus have affected the hydrological processes in the river’s lower reaches and caused delta degradation. 相似文献
15.
The hydrological and morphological features of the Chao Phraya Mouth Area (Thailand) are considered. The attention is focused
on the assessment of the effect exerted on the hydrological and morphological processes in the delta and the nearshore of
the Chao Phraya River by a considerable anthropogenic drop in water and sediment runoff of the river; land subsidence near
Bangkok caused by groundwater withdrawal; sea level rise; and wave intensification. 相似文献
16.
Steven M. Nelson Eloise Kendy Karl W. Flessa J. Eliana Rodríguez-Burgueño Jorge Ramírez-Hernández Tomás E. Rivas-Salcedo 《水文研究》2020,34(22):4156-4174
The macrotidal Colorado River Delta at the northern end of the Gulf of California in Mexico is hydrologically complex. We review historical accounts, data, field notes and photographs to evaluate the hydrological processes active on the delta prior to the advent of upstream dams. We also employ satellite imagery as well as recent LIDAR data to illustrate the critical role played by headcut erosion in restoring the river's fluvial/tidewater connection during the 1979–1988 floods. Prior to human manipulation, the river's contribution of fresh water to the Gulf was periodically interrupted by natural overflowing, avulsing, and flooding into the sub-sea level Salton Sink on the north slope of the delta plain. River flow south towards the Gulf was also subject to occasional overflow into Laguna Salada, another sub-sea level basin. In the mid-20th century, the Delta was disconnected from its fluvial supply following installation of upstream dams and reservoirs. A tidal sediment obstruction developed in the estuary channel, forming a final barrier to fluvial connectivity. Release of Colorado River floodwaters into Mexico between 1979 and 1988 provided a natural experiment on the hydrological response of a long-disconnected macrotidal delta to restoration of fluvial supply. 相似文献
17.
《Continental Shelf Research》2007,27(3-4):296-308
This paper focuses on the delivery of water and sediment to the northern Adriatic to better understand the short-term evolution of continental margin sedimentation under natural and human impact. For that reason, the Po and six Apennine rivers (Metauro, Musone, Potenza, Tronto, Chienti and Pescara) are investigated. The climate-driven hydrological model HydroTrend is used to simulate discharge and sediment loads where observational data are limited. The northern Apennine hinterland has a significant impact on the sediment flux leaving the Po River, contributing 56% of the sediment it delivers to the Adriatic Sea. The Po River experienced a strong decrease in its sediment load (17.2–6.4 Mt/yr) across 1933–1987, in contrast to a small increase in its water discharge. The rivers draining the southern Apennine hinterland contribute more than 50% of the sediment load entering the Adriatic Sea, and this is in spite of human modification of their discharge through numerous small reservoirs that invariably reduce a river's sediment load. As a result, hyperpycnal flows, which historically carried 20–40% of the sediment flux from these Apennine rivers, become rare. Sediment load reduction is also reflected by retreat of the Apennine coastline. Based on the ART model (used in HydroTrend), the total sediment load to the northern Adriatic is 43 MT/yr where the northern Alpine rivers contribute 8 MT/yr, the Po River 13 MT/yr and the Apennine rivers contribute 22 MT/yr. 相似文献
18.
M. V. Mikhailova 《Water Resources》2011,38(4):438-452
General geographic features of the Thames River, its basin, and mouth area, consisting of the tidal mouth reach of the river,
a large estuary, and an open nearshore zone of the river mouth (the North Sea coastal zone) are discussed. The peculiarities
of river and sea hydrological factors responsible for the regime of the Thames River mouth area are described in detail. Characteristics
of the river water runoff were specified and supplemented by the data on the river inundations in the area of London. Particular
emphasis was placed on variations in the mean sea level in the area of the Thames River mouth as well as on specific features
of tides and storm surges in the area of the sea inlet into the estuary. Main regularities in the estuary evolution during
Holocene and present-day morphological processes in the Thames River mouth area were revealed. 相似文献
19.
L. M. Sorokovikova G. I. Popovskaya V. N. Sinyukovich I. V. Tomberg N. V. Bashenkhaeva N. A. Tashlykova 《Water Resources》2006,33(3):321-328
Results of comprehensive studies that were carried out during freezing period in the lower reaches of the Selenga River and in water bodies located within its delta revealed peculiarities of water chemistry, phytoplankton species composition, and the characteristic features of alga development. Quantitative assessment of algae is also presented. 相似文献
20.
D. V. Magritskii 《Water Resources》2011,38(6):709-719
Data of network and expedition measurements and information about water management arrangements were used to study in detail
the peculiarities of along-channel and long-term variations in the major characteristics of suspended sediment runoff in the
lower reach and the delta of the Kuban River. For characteristics periods, the annual volumes of actual and estimated sediment
runoff and the contribution of economic activity in its variations are evaluated and possible changes in sediment runoff characteristics
in the XXI century are forecasted. The specific features, values, and causes of sediment runoff transformation in Kuban delta
in the past and the present are analyzed; sediment balance in the delta is calculated. 相似文献