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1.
Vassilis Z. Antonopoulos Soultana K. Gianniou Athanasios V. Antonopoulos 《水文科学杂志》2013,58(14):2590-2599
ABSTRACTEvaporation is one of the most important components in the energy and water budgets of lakes and is a primary process of water loss from their surfaces. An artificial neural network (ANN) technique is used in this study to estimate daily evaporation from Lake Vegoritis in northern Greece and is compared with the classical empirical methods of Penman, Priestley-Taylor and the mass transfer method. Estimation of the evaporation over the lake is based on the energy budget method in combination with a mathematical model of water temperature distribution in the lake. Daily datasets of air temperature, relative humidity, wind velocity, sunshine hours and evaporation are used for training and testing of ANN models. Several input combinations and different ANN architectures are tested to detect the most suitable model for predicting lake evaporation. The best structure obtained for the ANN evaporation model is 4-4-1, with root mean square error (RMSE) from 0.69 to 1.35 mm d?1 and correlation coefficient from 0.79 to 0.92.
EDITOR M.C. AcremanASSOCIATE EDITOR not assigned 相似文献
2.
Abstract Long term research has been conducted into the hydrological effects of different land usage of a wetland mire in southern Germany. Drainage for agriculture lowered the water table and reduced evaporation from about 110% of open water losses to just under the Penman short grass potential rate. The runoff regime was altered and peak flows increased. Afforestation of agricultural land increased evaporation losses to much higher levels than open water evaporation, and annual runoff was nearly halved. Forest growth reduced soil water and baseflows. Peak flows became smaller; the rate of reduction was particularly rapid in the early years of tree growth. 相似文献
3.
《水文科学杂志》2013,58(6)
Abstract Abstract Evaporation is one of the fundamental elements in the hydrological cycle, which affects the yield of river basins, the capacity of reservoirs, the consumptive use of water by crops and the yield of underground supplies. In general, there are two approaches in the evaporation estimation, namely, direct and indirect. The indirect methods such as the Penman and Priestley-Taylor methods are based on meteorological variables, whereas the direct methods include the class A pan evaporation measurement as well as others such as class GGI-3000 pan and class U pan. The major difficulty in using a class A pan for the direct measurements arises because of the subsequent application of coefficients based on the measurements from a small tank to large bodies of open water. Such difficulties can be accommodated by fuzzy logic reasoning and models as alternative approaches to classical evaporation estimation formulations were applied to Lake Egirdir in the western part of Turkey. This study has three objectives: to develop fuzzy models for daily pan evaporation estimation from measured meteorological data, to compare the fuzzy models with the widely-used Penman method, and finally to evaluate the potential of fuzzy models in such applications. Among the measured meteorological variables used to implement the models of daily pan evaporation prediction are the daily observations of air and water temperatures, sunshine hours, solar radiation, air pressure, relative humidity and wind speed. Comparison of the classical and fuzzy logic models shows a better agreement between the fuzzy model estimations and measurements of daily pan evaporation than the Penman method. 相似文献
4.
BORIS SEVRUK 《水文科学杂志》2013,58(2):231-236
ABSTRACT The evaporation losses from the container of an old galvanized Hellmann gauge, 7·1 cm2 aperture area, were five times greater than the losses from the container of a new gauge, 1·8 cm2 aperture area, of almost the same grey colour. The maximum evaporation from the old gauge amounted to 0·75 mm per day. The same evaporation losses in the Baye of Montreux basin over a period of 10 years from April to September amounted to 0·09 mm per measurement or to 0·7 per cent of the precipitation catch. There is a relationship between the monthly percentage evaporation losses and the ratio of evaporation time and rainfall duration (r = 0·803). 相似文献
5.
During 1998/1999, surface and subsurface sediment samples were collected along the entire length of the Spokane River from its outlet at the northern end of Lake Coeur d'Alene (CDA), Idaho, to Lake Roosevelt on the Columbia River, Washington. The study was conducted to determine if the trace element enrichments observed in Lake CDA and on the floodplain and in the CDA River extend through the Spokane River Basin (SRB). As in Lake CDA, surface sediments in the SRB are enriched in Pb, Zn, As, Cd, Sb and Hg relative to local background levels. Pb, Cd and Zn are the most elevated, with maximum enrichment occurring in the upper Spokane River in close proximity to Lake CDA. On average, enrichment decreases downstream, apparently reflecting both increased distance from the inferred source (the CDA River Basin), as well as increased dilution by locally derived but unenriched materials. Only Cd and Zn display marked enrichment throughout the SRB. Pb, Zn and Cd seem to be associated mainly with an operationally defined iron oxide phase, whereas the majority of the As and Sb seem to be matrix‐held. Subsurface sediments also are enriched in Pb, Zn, As, Cd, Sb and Hg relative to background levels. Based on 137Cs and excess 210Pb dating, trace element enrichment began in the middle part of the SRB (Long Lake) between 1900 and 1920. This is contemporaneous with similar enrichments observed in Lake CDA, as well as the completion of Long Lake Dam (1913). In the most downstream part of the basin (Spokane River Arm of Lake Roosevelt), enrichment began substantially later, between 1930 and 1940. The temporal difference in enrichment between Long Lake and the River Arm may reflect the latter's greater distance from the presumed source of the enrichment (the CDA River Basin); however, the difference is more likely the result of the completion of Grand Coulee Dam (1934–1941), which formed Lake Roosevelt, backed up the Spokane River, and increased water levels in the River Arm by about 30 m. 相似文献
6.
Dr. R. O. van EVERDINGEN 《水文科学杂志》2013,58(3):33-39
Abstract A synthetic diurnal energy budget averaged for each month of the year shows that Lake Ontario loses very little heat at night during April, May, and June. The nightly losses during July, August, and September are conjectured to contribute significantly to the deepening of the thermocline through vertical convection. 相似文献
7.
John v. G. GSCHWENDTNER 《水文科学杂志》2013,58(3):64-70
Abstract Valencia Lake, in northern Venezuela, and its tributary area (the catchment is approximately seven times larger than the lake which has an area of about 350 km2) are completely isolated from any river system or sea. The lake is about 400 m above sea level, and the adjacent ranges are up to 2,000 m higher. Observations of the fluctuations of the lake level since 1901 exist (with sporadic data since 1700), along with data on rainfall in the watershed and near the lake for the same period of time. Since 1939, 21 mostly small, tributary rivers have been hydrologically controlled. Evaporation (class A pan) has been observed also during this time. Since the tributary Rivers dry out for severall months each year, the lake descends as a function of its evaporation and serves as a large evaporation pan. The mean annual value is about 2,000 mm. By balancing losses (evaporation) against gains (runoff plus direct rain on the lake) a “hydrological pattern” was developed for the 61 years of fluctuation record; it was rechecked the last 22 years using the additional data. Yearly percentages as a function of the average were calculated. 相似文献
8.
《水文科学杂志》2013,58(6)
Abstract Abstract The water balance of Lake Nainital in the Kumaun Himalaya, India was previously computed using water budgeting and other indirect methods. An important data set of stable oxygen and hydrogen isotopic composition of water sources of the lake region was also presented and used to verify the annual estimates of subsurface flow/water balance. In the present study, the same data set has been used to investigate the dynamics of this lake in terms of the seasonal processes operative during the annual hydrological cycle: increased inflow during the monsoon, delayed groundwater inflow, and stratification and mixing of water. Based on the available data, a simple two-box model was used to constrain the values of exchange coefficients between the hypolimnion and epilimnion layers and to estimate evaporation and outflow components from the isotopic data. 相似文献
9.
B. HENDERSON-SELLERS 《水文科学杂志》2013,58(4):363-367
ABSTRACT It is shown that a numerical model for predicting the depth time variation of water temperature in a fresh water lake or reservoir can be used also for prediction of water losses due to evaporation. The seasonal change in peak evaporation from summer (in small lakes) to winter (in large lakes) is satisfactorily simulated. 相似文献
10.
I. KORKIGIAN 《水文科学杂志》2013,58(1):35-51
ABSTRACT This report describes an analytical approach to the problem of defining changes in the water levels of two lakes or reservoirs connected by a channel subjected to flow blockages or retardations due to ice. Routing equations for this purpose were derived for Lakes Michigan-Huron and Erie which form a portion of the Great Lakes system. Procedures were developed for computing the monthly winter flow retardation due to ice in the St. Clair River, the outlet channel for Lake Michigan-Huron. An examination of these flow retardations, 1899–1969, indicated that the degree of retardation has progressively diminished since 1920. Utilizing the routing equations derived, the effects of these reductions in the retardations were computed to have lowered the levels of Lake Michigan-Huron by 0·50 ft. Investigation of factors responsible for the reduction in the winter flow retardations lead to the conclusion that the major factor was man-made channel enlargements in the St. Clair River. 相似文献
11.
Reservoirs have to be released when repairing of the dams is necessary. In 1995, two reservoirs in Baden-Württemberg (Germany) of similar age and volume (Lake Herrenbach near Göppingen, 1.0 Mio. m3 and Lake Breitenau near Heilbronn, 2.3 Mio. m3) were emptied. This allowed the singular possibility to investigate the effects of drainage and refilling on the limnochemistry and the phytoplankton biocoenosis of such artificial lakes.Before the drainage of the reservoirs, both lakes showed phosphorus release from the sediment during summer stagnation. Phosphorus values of Lake Herrenbach were regularly higher than those of Lake Breitenau (Lake Herrenbach 88 μg/l, Lake Breitenau 33 μg/l). During release, both lakes indicated higher phosphorus and chlorophyll concentrations as well as rising biomasses. Remarkable differences were observed during refilling of the reservoirs: while Lake Herrenbach showed higher transparency and lower phosphorus concentrations, Lake Breitenau progressed towards eutrophication (total phosphorus during summer 1996: Lake Herrenbach 30 μg/l, Lake Breitenau 55 μg/l). One reason for the reaction of Lake Breitenau was the reduced ground drainage during the refilling, which caused an accumulation of nutrients in the hypolimnion. Another reason was the mineralisation of vegetation which covered great parts of the dry lake sediment. The limnological change of Lake Herrenbach was not as clear but could be caused by the restauration of the pre-reservoir which was drainaged and dredged before the emptying of the main reservoir started as well as many other facts which differed Lake Herrenbach from Lake Breitenau. 相似文献
12.
Abstract Poyang Lake is the largest freshwater lake in China, and plays a major role in flood mitigation, restoration and conservation of the ecological environment in the middle Yangtze River basin. Sediment load and streamflow variations in Poyang Lake basin are important for the scouring and deposition changes of this lake. However, these hydrological processes are heavily influenced by human activities, such as construction of water reservoirs, and land-use/land cover changes. By thorough analysis of long series of sediment and streamflow obtained from five major hydrological stations, we systematically investigated the spatial and temporal patterns of these hydrological processes and the hydrological responses to human activities using the Mann-Kendall trend test, the double cumulative mass curve and the linear regression method. The results show: (1) no significant change in streamflow followed by an increasing tendency after the 1990s that turns to be decreasing about 2000; and (2) a sharp increase of sediment load during the late 1960s and 1970s triggered by extensive deforestation (during the “Cultural Revolution” in China) followed by a tendency to decrease after the early 1980s. Construction of water reservoirs has greatly reduced the sediment load of the Poyang Lake basin, and this is particularly the case in the Ganjiang River, where the sediment load changes may be attributed to the trapping effects of the Wan'an Reservoir, the largest water reservoir within the Poyang Lake basin. There is no evidence to corroborate the influence of water reservoirs on the streamflow variations. It seems that the streamflow variations are subject mainly to precipitation changes, but this requires further analysis. The current study may be of scientific and practical benefit in the conservation and restoration of Poyang Lake, as a kind of wetland, and also in flood mitigation in the middle Yangtze River basin that is under the influence of human activities. Citation Zhang, Q., Sun, P., Jiang, T. & Chen, X.-H. (2011) Spatio-temporal patterns of hydrological processes and their hydrological responses to human activities in the Poyang Lake basin, China. Hydrol. Sci. J. 56(2), 305–318. 相似文献
13.
Boyd A. HUTCHISON 《水文科学杂志》2013,58(1):34-42
ABSTRACT During the spring of 1961, evaporation from snow and soil surfaces was measured in the central Rocky Mountains near Fraser, Colorado. Measurements were made in natural forest openings at 9,000 feet elevation. Evaporation from wet soil surfaces greatly exceeded evaporation from nearby snow. There was little evidence of transfer of vapor from soil to nearby patches of snow, but as areas of bare, wet soil increased and evaporation amounts from such surfaces increased, evaporation from snow decreased. It was concluded that, as greater amounts of water evaporated from soils, the vapor pressure of the air was raised sufficiently to reduce evaporation from snow. Since transfer of vapor from soil to snow appeared small at best, evaporation losses from snow and soil surfaces essentially constituted a total moisture loss from the area. 相似文献
14.
《水文科学杂志》2013,58(4)
Abstract Abstract An annual water balance model of Lake Victoria is derived for the period 1925–2000. Regression techniques are used to derive annual inputs to the water balance, based on lake rainfall data, measured and derived inflows and estimated evaporation during the historical period. This approach acknowledges that runoff is a nonlinear function of lake rainfall. A longer inflow series is produced here which is representative of the whole inflow to the lake, rather than just from individual tributaries. The results show a good simulation of annual lake levels and outflows and capture the high lake level in 1997–1998. Climate change scenarios, from a recent global climate model experiment, are applied to the lake rainfall inflow series and evaporation data to estimate future water balances of the lake. The scenarios produce a potential fall in lake levels by the 2030s horizon, and a rise by the 2080s horizon. A discussion of the application of climate change data to this complex hydrological system is presented. 相似文献
15.
Evolution of the Upper Rhone River discharge and suspended sediment load during the last 80 years and some implications for Lake Geneva 总被引：1，自引：0，他引：1
16.
Josip Rubinić 《水文科学杂志》2013,58(10):1908-1924
AbstractVrana Lake in Dalmatia is a karstic kryptodepression connected to the nearby sea through the karstic subsoil and a canal. Due to interactions with the sea, lake water salinity increases greatly during severe dry periods, seriously endangering the ecosystem. Trend analysis (1961–2010) reveals a decrease in precipitation and surface inflow, but an increase in air temperature, and in sea and lake water levels. Lake inflow and water losses are only partially monitored. Average annual inflow from the monitored part of the catchment is 1722 m3 s-1, but total inflow is significantly greater; the average difference between total inflow and cumulative water losses is 3072 m3 s-1. The paper uses modelling to evaluate total inflow into the lake system, taking into consideration projected climate changes/variations till 2100 from the RegCM3 and ALADIN climate models. The analysis indicates marked decrease in discharge values by the end of this century, by as much as 60%.
Editor Z.W. Kundzewicz 相似文献
17.
Analyses of the response by a weighing lysimeter in Kioloa State Forest during and after rainfall provided values of interception loss rate. The derived rates for time scales between 0.1 and 1.0mm h?1 were generally similar throughout storm events to losses determined from throughfall and stemflow observations. During post-rainfall periods of canopy drying, enhanced rates of lysimeter evaporation were consistent with micrometeorological determinations of the partitioning of available radiant energy, based on atmospheric gradients of humidity and temperature. Interception losses from the eucalypt forest, deduced from the lysimeter response, varied between 10 and 15 per cent of gross rainfall in three consecutive 12 month periods whereas the corresponding rainfall ranged between 590 and 1530 mm yr?1. Daytime losses accounted for about two-thirds of total interception loss with a similar fraction occurring during rain periods. Storage capacity of the evergreen forest canopy was inferred to be 0.35 mm. Hourly loss rates during rainfall ranged up to 0.8 mm h?1 but with decreasing mean values and variability with increasing time scale resulting in a monthly mean value computed for the total number of hours of rain of approximately 0.1 mm h?1. A preliminary analysis of loss rate in terms of storm windspeed and rainfall intensity explained about half of its variation in statistically derived relationships. Improved time resolution of the order of seconds was considered a prerequisite to the physical understanding of turbulent transport from saturated canopies. The small value of interception storage capacity was considered in relation to that for pine forest as a basis for explaining observed differences in interception behaviour between eucalypt forest and coniferous plantations in the same area. Large differences in interception losses between the Kioloa site and evergreen forest in the South Island of New Zealand and also eucalypt forest in Western Australia were attributed to dissimilar meteorological conditions at the various sites. 相似文献
18.
Turgay Partal 《水文科学杂志》2013,58(13):2455-2464
ABSTRACTThis study focuses on the variability of lake evaporation and also the periodic relationships among hydro-meteorological variables. The monthly hydro-meteorological data of Lake Keban were investigated by wavelet transforms. The results show that the main periodicity is on an annual scale. This periodicity is weaker for precipitation and wind speed but higher for evaporation, temperature, runoff and relative humidity. In addition to this, the continuous wavelet figures show some weak periodicities on the almost 10-year scale level but they are not continuous over time. Also, strong events on a short-term monthly scale are seen for evaporation, precipitation and runoff in 1988. This event in 1988 may be explained by the 1988 La Niña event, which was one of the strongest on record. Also, the periodicities on the 2–8-month scales in the precipitation data can be interpreted as being connected with the strong El Niño events of 1982 and 1992.
Editor D. Koutsoyiannis; Associate editor A. Carsteanu 相似文献
19.
A. Hassani 《Water Resources》2013,40(6):621-630
Knowing the rate of evaporation from surface water resources such as channels and reservoirs is essential for precise management of the water balance. Few detailed evaporation studies exist for small lakes or reservoirs in arid regions of the world. In this study, monthly evaporation was determined by Bowen Ratio Energy Budget technique (BREB) for Alghadir reservoir (Saveh, Iran) from 1995–2007 and compared with class-A pan. Daily data were obtained from IMO (Iran Meteorological Organization) weather station, located near the reservoir, for all of these years. Some variations have been observed on the estimated evaporation of the energy budget at different years, ranging from 151 cm for 1997 to 174 cm for 2006. There is no specific evaporation pattern for all the years, but evaporation rates were low in winter (January and February) and highest during the summer (July and August). However, the times and month of highest evaporation rates varied during the study period. Surveying of reservoir thermal structure showed that, inflow and outflow energy fluxes to this water volume have large variations. In addition, incoming solar shortwave radiation, incoming atmospheric longwave radiation, and longwave atmospheric radiation emitted from the water surface are largest energy fluxes for this small and deep reservoir. Results of this study could explain the importance and sensible contribution of the evaporation rates as a fundamental parameter in the hydrological cycle of reservoirs ecosystem in the arid regions of Iran. 相似文献
20.
《水文科学杂志》2013,58(3)
Abstract Abstract Accurate estimates of water losses from mature Sitka spruce (Picea sitchensis) plantations in the UK uplands are required to assess the sustainability of water supply in the event of land-use change. Many investigations have demonstrated that afforestation increases water losses from temperate upland catchments, to up to 40% of annual site rainfall. In a 0.86 km2 upland water supply catchment in southwest Scotland, interception loss in a Sitka spruce-dominated 37-year old plantation, was 52% of annual precipitation (2912 mm), considerably higher than reported in previous studies of similar catchments. From direct measurements of rainfall, cloudwater, discharge and soil evaporation, the catchment water balance was 96–117% complete, within the limits of measurement error. The most probable explanation for the higher forest interception loss reported here is the inclusion of cloudwater measurements. 相似文献