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1.
Foreword Asoneofthethreegreatdiscoveriesin 1 970s ,thefractaltheoryhasbeenwidelyappliedinmanyfieldsconcerningthesciencesofnatureandthehumanities .Atpresent ,thefractaltheoryhasbeenappliedintherelatedanalysisofwatersystemordisaster .However ,thestud iesonnatureofrelationshipbetweenthewholewatersysteminChinaanddisasterfractalanaly sisarestillintheirinitialperiod .Thepaperpresentsafractaldimensionof 7drainagebasinsandthefloodinChinaaswellastheirpossiblerelations .Itishopedthatthepaperwouldbehe…  相似文献   
2.
Moore, R.D. (Dan), J.W. Trubilowicz, and J.M. Buttle, 2011. Prediction of Streamflow Regime and Annual Runoff for Ungauged Basins Using a Distributed Monthly Water Balance Model. Journal of the American Water Resources Association (JAWRA) 48(1): 32‐42. DOI: 10.1111/j.1752‐1688.2011.00595.x Abstract: Prediction of streamflow in ungauged basins is a global challenge, but is particularly an issue in physiographically complex regions like British Columbia (BC), Canada. The objective of this study was to assess the accuracy of a simple water balance model that can be run using existing spatial datasets. The model was developed by modifying an existing monthly water balance model to account for interception loss from forest canopy, glacier melt, and evaporation from lakes. The model was run using monthly climate normals from the ClimateBC application, which have a horizontal resolution of 400 m. Each ClimateBC grid cell was classified as forest, open land, glacier or water surface based on provincial scale digital maps of biogeoclimatic zones, glaciers, and water. The output was monthly mean runoff from each grid cell. These values were integrated within the catchment boundaries for streams gauged by the Water Survey of Canada. Annual runoff was predicted with modest accuracy: after updating the predicted runoff by interpolating errors from neighboring gauged streams, the mean absolute error was 25.4% of the gauged value, and 52% of the streams had errors less than 20%. However, the model appears to be quite robust in distinguishing between pluvial, hybrid, and melt‐dominated hydroclimatic regimes, and therefore has promise as a tool for catchment classification.  相似文献   
3.
Jin, Xin and Venkataramana Sridhar, 2012. Impacts of Climate Change on Hydrology and Water Resources in the Boise and Spokane River Basins. Journal of the American Water Resources Association (JAWRA) 48(2): 197‐220. DOI: 10.1111/j.1752‐1688.2011.00605.x Abstract: In the Pacific Northwest, warming climate has resulted in a lengthened growing season, declining snowpack, and earlier timing of spring runoff. This study characterizes the impact of climate change in two basins in Idaho, the Spokane River and the Boise River basins. We simulated the basin‐scale hydrology by coupling the downscaled precipitation and temperature outputs from a suite of global climate models and the Soil and Water Assessment Tool (SWAT), between 2010 and 2060 and assess the impacts of climate change on water resources in the region. For the Boise River basin, changes in precipitation ranged from ?3.8 to 36%. Changes in temperature were expected to be between 0.02 and 3.9°C. In the Spokane River region, changes in precipitation were expected to be between ?6.7 and 17.9%. Changes in temperature appeared between 0.1 and 3.5°C over a period of the next five decades between 2010 and 2060. Without bias‐correcting the simulated streamflow, in the Boise River basin, change in peak flows (March through June) was projected to range from ?58 to +106 m3/s and, for the Spokane River basin, the range was expected to be from ?198 to +88 m3/s. Both the basins exhibited substantial variability in precipitation, evapotranspiration, and recharge estimates, and this knowledge of possible hydrologic impacts at the watershed scale can help the stakeholders with possible options in their decision‐making process.  相似文献   
4.
The aim of the present work was to establish the kinetics for the degradation of doxycycline in the aquatic environment with a view to arriving at a kinetic model that can be used to predict the persistence of antibiotic with confidence. The degradation of doxycycline in both water and sediment phases of aquatic microcosm experiments, as well as in distilled water control experiments, was studied over a period of 90 days. An initial 21% loss due to adsorption by the sediment was observed in the microcosm experiment soon after charging. Biphasic zero-order linear rates of degradation, attributed to microbial degradation of the free and sediment or colloidal particle-adsorbed antibiotic, were observed for both water phase (2.3 × 10?2 and 4.5 × 10?3 μgg?1 day?1) and sediment phase (7.9 × 10?3 and 1.5 × 10?3 μgg?1 day?1) of the microcosm experiment. The covered distilled water control experiment exhibited a monophasic zero-order linear rate (1.9 × 10?3 μgg?1 day?1) attributed to hydrolysis, while the distilled water experiment exposed to natural light exhibited biphasic liner rates attributed to a combination of hydrolysis and photolysis (2.9 × 10?3 μgg?1 day?1) and to microbial degradation (9.8 × 10?3 μgg?1 day?1). A kinetic model that takes into account hydrolysis, photolysis, microbial degradation as well as sorption/desorption by colloidal and sediment particles is presented to account for the observed zero-order kinetics. The implications of the observed kinetics on the persistence of doxycycline in the aquatic environment are discussed.  相似文献   
5.
ABSTRACT: Wastewater from a municipal treatment plant was applied in rapid infiltration basins for four years to determine a poorly drained soils effectiveness in removing influent N and P and the soil changes that might limit their removal. About half the total PO4-P lost from the influent was sorbed in the upper 91 cm of the soil and the other half was sorbed by the soil below the perforated pipe, which was used to drain the basins and collect the effluent for analysis. Drying of the basin soils converted more sorbed PO4-P to Ca phosphates but the total sorbed was about the same. The in. fluent N decreased, probably by volatilization, because the two basins with surface soil lost soil N rather than gained soil N. The soil total Ca, Mg, and K contents did not change significantly but Na increased slightly. Changes in the physical characteristics of the soils were slight and would have little effect on the longevity of a rapid infiltration basin.  相似文献   
6.
ABSTRACT: Three urban runoff models, namely, the Road Research Laboratory Model (RRLM), the Storm Water Management Model (SWMM) and the University of Cincinnati Urban Runoff Model (UCURM), were examined by comparing the model simulated hydrographs with the hydrographs measured on several instrumented urban watersheds. This comparison was done for the hydrograph peak points as well as for the entire hydrographs using such statistical measures as the correlation coefficient, the special correlation coefficient and the integral square error. The results of the study indicated that, when applying the three selected non-calibrated models on small urban catchments, the SWM model performed marginally better than the RRL model and both these models were more accurate than the UCUR model. On larger watersheds, the comparisons between the SWM model and the other two models would be likely even more favourable for the SWM model, because it has the most advanced flow routing scheme among the studied models.  相似文献   
7.
In the Heihe River Basin in the arid inland area of northwest China, the distribution of water resources in vegetation landscape zones controls the ecosystems. The carbon sequestration capacity of vegetation is analyzed in relation to water resources and vegetation growing conditions. During the last 20 years, the vegetation ecosystems have degenerated in the Heihe River Basin. Simulation using the C-FIX model indicates that, at present, the total amount of NPP of vegetation accounts for about 18.16 TgC, and the average value is 106 gC/m(2)/yr over the whole basin. NPP has generally the highest value in the upperstream mountain area, middlestream artificial oases area, downstream river bank area, alluvial fan and the terminal lake depression where vegetation grows relatively well. The lowest value is found in the vast downstream desert and Gobi area. Protection of vegetation ecosystems and enhancement of carbon sequestration require such inland river basins as the Heihe River Basin to be brought under management in a comprehensive way, taking water as a key, to carry out a rational and efficient allocation and utilization of water resources.  相似文献   
8.
An 11-year period of water quality data, collected by the Directorate of Sate Water Works of Turkey are thoroughly analyzed for the purpose of implementing water quality classes to water resources in the Meric Basin, located on the European land mass of Turkey. Water quality parameters are divided into four groups as physical, organic, inorganic, and bacteriological. The quality class of each group is evaluated by taking into account the poorest quality of any parameter in the group, after which a quality rank is assigned to the sampling station and the waterbody in question. This method of water quality classification imposed by the Turkish Water Quality Act, is then criticized with respect to a statistical approach.  相似文献   
9.
In this study, we look at the evolution of a cooperative water regime in the delta of the Rhine catchment. In a Dutch–German case study, we focus on cross-border cooperation on the local and regional scale, describing and analyzing how a remarkably resilient and robust transboundary water regime has evolved over the course of 50 years. Context-, interest- and knowledge-based explanations contribute important insights into the evolution of the Deltarhine regime, and it is shown that the legal, institutional and socio-economic context shapes and constrains regional cross-border cooperation. Surprisingly in this regard, we find that European water directives have not yet played a decisive, catalyzing role for policy harmonization across borders. Finally, we show that key individuals play a crucial role in regime formation and development. We suggest that the presence of entrepreneurs and leaders adds explanatory power to current conceptual frameworks in international river basin management, thus meriting further research.  相似文献   
10.
Disappearance rate constants are reported for the reductive transformation of 17 halogenated aliphatic hydrocarbons in anaerobic sediment-water samples. Statistical experimental design in combination with multivariate chemical characterization of their chemical properties was used to select the compounds. Degradation followed pseudo first-order kinetics through at least two half-lives for 15 of the 17 compounds. Of all the compounds investigated, 1,2,3-trichloropropane and dichloromethane were unique in that they were dehalogenated according to zero-order kinetics. Reductive dehalogenation was the sole transformation reaction taking place.  相似文献   
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