Papers by Karim Abbaspour
Statistical Modelling of global geogenic arsenic contamination in groundwaters
Modeling blue and green water availability in Africa
Water Resources Research, 2008
... Surface runoff was simulated using a modification of the SCS Curve Number (CN) method. Despit... more ... Surface runoff was simulated using a modification of the SCS Curve Number (CN) method. Despite the empirical nature, this approach has been proven to be successful for many applications and a wide variety of hydrologic conditions [Gassman et al., 2007]. ...
Mapping risk of cadmium and lead contamination to human health in soils of Central Iran
The Science of the total environment, Jan 15, 2005
In order to map Cd and Pb contamination in the soils of the region of Isfahan, Central Iran, we p... more In order to map Cd and Pb contamination in the soils of the region of Isfahan, Central Iran, we performed indicator kriging on a set of 255 topsoil samples (0-20 cm) gathered irregularly from an area of 6800 km(2). The measured Cd concentrations exceeded the Swiss guide value in more than 80% of the samples whereas Pb concentrations exceeded the respective guide value only in 2% of the samples. Based on the simulated conditional distribution functions, the probability of exceeding the concentration of Cd and Pb from the specific threshold was computed. The results indicated that in most parts of the region the probability of contamination by Cd is very large (>0.95) whereas it is small (<0.5) for Pb. Based on a misclassification analysis, we chose the probability of 0.45 as optimum probability threshold to delineate the polluted from unpolluted areas for Cd. In addition, we performed a loss analysis to separate risks to human health from potential losses due to remediation cos...
Assessing the impact of climate change on water resources in Iran
Water Resources Research, 2009
... Iran is a country of large climatic variability from north to south. ... We specifically look... more ... Iran is a country of large climatic variability from north to south. ... We specifically looked at the changes in various components of the water balance including precipi-tation andevapotranspiration distribution, river discharge, soil moisture, and aquifer recharge. ...
Environmental Earth Sciences, 2010
One of the major causes of groundwater pollution in Hamadan-Bahar aquifer in western Iran is a no... more One of the major causes of groundwater pollution in Hamadan-Bahar aquifer in western Iran is a nonpoint source pollution resulting from agricultural activities. Withdrawal of over 88% of drinking water from groundwater resources, adds urgency to the studies leading to a better management of water supplies in this region. In this study, the DRASTIC model was used to construct groundwater vulnerability maps based on the ''intrinsic'' (natural conditions) and ''specific'' (including management) concepts. As DRASTIC has drawbacks to simulate specific contaminants, we conditioned the rates on measured nitrate data and optimized the weights of the specific model to obtain a nitrate vulnerability map for the region. The performance of the conditioned DRASTIC model improved significantly (R 2 = 0.52) over the intrinsic (R 2 = 0.12) and specific (R 2 = 0.19) models in predicting the groundwater nitrate concentration. Our study suggests that a locally conditioned DRASTIC model is an effective tool for predicting the region's vulnerability to nitrate pollution. In addition, comparison of groundwater tables between two periods 30 years apart indicated a drawdown of around 50 m in the central plain of the Hamadan-Bahar region. Our interpretation of the vulnerability maps for the two periods showed a polluted zone developing in the central valley requiring careful evaluation and monitoring.
Journal of Geographic Information System, 2012
Validity of CA-Markov in land use and cover change simulation was investigated at the Langat Basi... more Validity of CA-Markov in land use and cover change simulation was investigated at the Langat Basin, Selangor, Malaysia. CA-Markov validation was performed using validation metrics, allocation disagreement, quantity disagreement, and figure of merit in a three-dimensional space. The figure of merit, quantity error, and allocation error for total landscape simulation using the 1990-1997 calibration data were 5.62%, 3.53%, and 6.13%, respectively. CA-Markov showed a poor performance for land use and cover change simulation due to uncertainties in the source data, the model, and future land use and cover change processes in the study area.
Water, Air, & Soil Pollution, 2005
Due to potential problems associated with their toxicities, concentration of heavy metals in soil... more Due to potential problems associated with their toxicities, concentration of heavy metals in soils is of great environmental concern. To evaluate Cd content, its spatial pattern, and availability in the surface soils of agricultural, industrial and urban regions of Isfahan, central Iran, we collected 255 topsoil samples (0–20 cm) from the nodes of an irregular grid in a study area
Water Resources Research, 1997
A parameter estimation procedure, sequential uncertainty domain parameter fitting (SUFI), is pres... more A parameter estimation procedure, sequential uncertainty domain parameter fitting (SUFI), is presented and has the following characteristics. The procedure is sequential in nature, meaning that one more iteration can always be made before choosing the final estimates. The procedure has a Bayesian framework, indicating that the method operates within uncertainty domains (prior, posterior) associated with each parameter. The procedure is
Water Research, 2010
The water transfer China a b s t r a c t This study applied game theory based models to analyze a... more The water transfer China a b s t r a c t This study applied game theory based models to analyze and solve water conflicts concerning water allocation and nitrogen reduction in the Middle Route of the South-to-North Water Transfer Project in China. The game simulation comprised two levels, including one main game with five players and four sub-games with each containing three sub-players. We used statistical and econometric regression methods to formulate payoff functions of the players, economic valuation methods (EVMs) to transform non-monetary value into economic one, cost-benefit Analysis (CBA) to compare the game outcomes, and scenario analysis to investigate the future uncertainties. The validity of game simulation was evaluated by comparing predictions with observations. The main results proved that cooperation would make the players collectively better off, though some player would face losses.
Evaluation of spatial and temporal variability of snow cover in a large mountainous basin in Iran
Nordic Hydrology, 2007
ABSTRACT
Vadose Zone Journal, 2004
, and seawater intrusion .
Soil Science Society of America Journal, 2000
model tries to describe the processes involved, the more complex it gets and, hence, the more dif... more model tries to describe the processes involved, the more complex it gets and, hence, the more difficult it becomes An important step in numerical modeling is the determination of to use. Greater model complexity also means introducmodel parameters. Because of practical limitations, as well as time and financial constraints, inverse algorithms have in recent years pre-tion of more parameters. Model parameters are genersented an attractive alternative to direct methods of parameter estima-ally unknown and difficult to measure, especially for tion. In this study we linked the inverse algorithm of SUFI with the field problems. simulation program LEACHM to study N turnover of an agricultural To estimate model parameters of a field study, inverse field. Addressing the inherent modeling uncertainties, we introduce modeling offers sometimes the only viable choice bethe concept of conditioned parameter distributions as being a more cause of time, expenses, practical limitations and inadeappropriate alternative to best-fit parameters. Conditioned parameter quacy of laboratory methods. Since N turnover is distributions are quantified within uncertainty domains, and the task strongly affected by microenvironmental conditions, adof an inverse model then is to reduce or condition this domain through ditional difficulties arise from the heterogeneity of soil minimization of an appropriate objective function. Propagating the properties, even on very small geographical scales uncertainty in the conditioned parameter distributions will result in simulations where most of the measurements are respected or fall (Becket and Webster, 1971). Neglecting spatial variabilwithin the 95% confidence interval of the Bayesian distribution ity can lead to unsatisfactory and often erroneous pre-(95PCIBD). In this study we used measured pressure heads and NO 3 diction results (Addiscott et al., 1991; Finke, 1993; Huwe concentrations to estimate 12 hydraulic parameters and up to 14 N and Totsche, 1995; Abbaspour et al., 1998).
Uncertainty in Estimation of Soil Hydraulic Parameters by Inverse Modeling: Example Lysimeter Experiments
Soil Science Society of America Journal, 1999
Effects of Cadmium, Copper, Lead, and Zinc Contamination on Metal Accumulation by Safflower and Wheat
Soil and Sediment Contamination, 2009
... GHOLAMABBAS SAYYAD,1 MAJID AFYUNI,2 SAYED-FARHAD MOUSAVI,3 KARIM C. ABBASPOUR,4 MOHAMMAD A. H... more ... GHOLAMABBAS SAYYAD,1 MAJID AFYUNI,2 SAYED-FARHAD MOUSAVI,3 KARIM C. ABBASPOUR,4 MOHAMMAD A. HAJABBASI,2 BRIAN K. RICHARDS,5 AND RAINER ... with Cd (Smolders and McLaughlin, 1996; Khoshgoftar et al., 2004) that may increase its solubility. ...
Plant and Soil, 2005
In a three-year factorial lysimeter study in Open Top Chambers (OTCs), we investigated the effect... more In a three-year factorial lysimeter study in Open Top Chambers (OTCs), we investigated the effect of topsoil pollution by the heavy metals Zn, Cu, and Cd on the water regime of newly established forest ecosystems. Furthermore, we studied the influence of two types of uncontaminated subsoils (acidic vs. calcareous) and two types of irrigation water acidity (ambient rainfall chemistry vs. acidified chemistry) on the response of the vegetation. Each of the eight treatment combinations was replicated four times. The contamination (2700 mg kg )1 Zn, 385 mg kg )1 Cu and 10 mg kg )1 Cd) was applied by mixing filter dust from a non-ferrous metal smelter into the upper 15 cm of the soil profile, consisting of silty loam (pH 6.5). The same vegetation was established in all 32 lysimeters. The model forest ecosystem consisted of seedlings of Norway spruce (Picea abies), willow (Salix viminalis), poplar (Populus tremula) and birch (Betula pendula) trees and a variety of herbaceous understorey plants. Systematic and significant effects showed up in the second and third growing season after canopies had closed. Evapotranspiration was reduced in metal contaminated treatments, independent of the subsoil type and acidity of the irrigation water. This effect corresponded to an even stronger reduction in root growth in the metal treatments. In the first two growing seasons, evapotranspiration was higher on the calcareous than on the acidic subsoil. In the third year the difference disappeared. Acidification of the irrigation water had no significant effect on water consumption, although a tendency to enhance evapotranspiration became increasingly manifest in the second and third year. Soil water potentials indicated that the increasing water consumption over the years was fed primarily by intensified extraction of water from the topsoil in the lysimeters with acidic subsoil, whereas also lower depths became strongly exploited in the lysimeters with calcareous subsoil. These patterns agreed well with the vertical profiles of fine root density related with the two types of subsoil. Leaf transpiration measurements and biomass samples showed that different plant species in part responded quite differently and occasionally even in opposite ways to the metal treatments and subsoil conditions. They suggest that the yearto-year changes in treatment effects on water consumption and extraction patterns were related to differences in growth dynamics, as well as to shifts in competitiveness of the various species. Results showed that the uncontaminated subsoil offered a possibility to compensate the reduction in root water extraction in the topsoil under drought, as well as metal stress.
Virtual water highway: water use efficiency in global food trade
Amid an increasing water scarcity in many parts of the world, virtual water trade as both a polic... more Amid an increasing water scarcity in many parts of the world, virtual water trade as both a policy instrument and practical means to balance the regional, national and global water budget has received much attention in recent years. Built upon the knowledge of virtual water accounting in the literature, this study examines the efficiency of the resource use embodied in the global virtual water trade from the perspectives of exporting and importing countries. Different characteristics between "green" and "blue" virtual water corresponding to rainfed and irrigated agriculture are elaborated. The investigation reveals that the virtual water flows primarily from countries of high water productivity to countries of low water productivity, generating a global saving of water resources. Meanwhile, the domination of green virtual water in the total virtual water trade constitutes low opportunity costs and environmental impacts as opposed to blue virtual water. The result...
Functional Relationship to Describe Drains with Entrance Resistance
Journal of Irrigation and Drainage Engineering, 2001
Model comparison of flow through a municipal solid waste incinerator ash landfill
Journal of Hydrology, 2001
The drainage discharge of a municipal solid waste incinerator (MSWI) bottom ash landfill was simu... more The drainage discharge of a municipal solid waste incinerator (MSWI) bottom ash landfill was simulated using various modelling approaches. Two functional models including a neural networks approach and a hydrological linear storage model, and two mechanistic models requiring physical/hydrodynamic properties of the waste material, HYDRUS5 and MACRO (Version 4.0) were used. The models were calibrated using an 8-month data set
Comparing uncertainty analysis techniques for a SWAT application to the Chaohe Basin in China
Journal of Hydrology, 2008
Distributed watershed models are increasingly being used to support decisions about alternative m... more Distributed watershed models are increasingly being used to support decisions about alternative management strategies in the areas of land use change, climate change, water allocation, and pollution control. For this reason it is important that these models pass ...
Journal of Hydrology, 2007
In a national effort, since 1972, the Swiss Government started the ''National Long-term Monitorin... more In a national effort, since 1972, the Swiss Government started the ''National Long-term Monitoring of Swiss Rivers'' (NADUF) program aimed at evaluating the chemical and physical states of major rivers leaving Swiss political boundaries. The established monitoring network of 19 sampling stations included locations on all major rivers of Switzerland. This study complements the monitoring program and aims to model one of the program's catchments -Thur River basin (area 1700 km 2 ), which is located in the north-east of Switzerland and is a direct tributary to the Rhine. The program SWAT (Soil and Water Assessment Tool) was used to simulate all related processes affecting water quantity, sediment, and nutrient loads in the catchment. The main objectives were to test the performance of SWAT and the feasibility of using this model as a simulator of flow and transport processes at a watershed scale. Model calibration and uncertainty analysis were performed with SUFI-2 (Sequential Uncertainty FItting Ver. 2), which was interfaced with SWAT using the generic iSWAT program. Two measures were used to assess the goodness of calibration: (1) the percentage of data bracketed by the 95% prediction uncertainty calculated at the 2.5 and 97.5 percentiles of the cumulative distribution of the simulated variables, and (2) the d-factor, which is the ratio of the average distance between the above percentiles and the standard deviation of the corresponding measured variable. These statistics showed excellent results for discharge and nitrate and quite good results for sediment and total phosphorous. We concluded that: in watersheds similar to Thurwith good data quality and availability and relatively small model uncertainty -it is 0022-1694/$ -see front matter ª a v a i l a b l e a t w w w . s c i e n c e d i r e c t . c o m j o u r n a l h o m e p a g e : w w w . e l s e v i e r . c o m / l o c a t e / j h y d r o l feasible to use SWAT as a flow and transport simulator. This is a precursor for watershed management studies. ª
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Papers by Karim Abbaspour