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To reduce flooding risks and improve urban drainage management, there is a need to increase the forecasting accuracy for rainfall models on small typical urban time and space scales. Increased rainfall forecasting accuracy will in turn improve runoff prediction and thus, prevent flooding hazards, decrease pollution discharge through combined sewers, increase waste water treatment efficiency, etc.

Heavy metal (HM)-polluted soil is a serious concern, especially as brackish water is widely used for irrigation purposes in water-scarce countries. In this study, the HYDRUS-2D model was used to simulate HM (copper (Cu), lead (Pb), and zinc (Zn)) transport through agricultural land cultivated with potato crops under surface drip irrigation to explore the potential groundwater contamination risk. T

The present study concerns disaggregation of daily rainfall time series into higher resolution. For this purpose, the scaling-based cascade model proposed by Olsson (1998) is employed. This model operates by dividing each rainy time period into halves of equal length and distributing the rainfall volume between the halves. For this distribution three possible cases are defined, and the occurrence

Soil physicochemical properties and macropore spatial structure affect saturated hydraulic conductivity (Ks). However, due to regional differences and long measurement time, Ks is tedious to quantify. Therefore, it is of great importance to find simplified but robust methods to predict Ks. One possibility is to use pedo-transfer functions (PTFs). Along this line, stratified sampling was carried ou

Spatial properties of field soils vary in a complex manner. Especially in arid and semiarid areas, this variability affects plant quality and crop production. An experimental field plot was extensively sampled regarding soil water (378 gravimetrical samples), soil chemical content (314 samples), and crop yield and chemical content (26 samples) at the Cherfech agricultural field research station in

The multifractal properties of daily rainfall were investigated in two contrasting climates: an east Asian monsoon climate (China) with an extreme rainfall variability and a temperate climate (Sweden) with a moderate rainfall variability. First, daily time series were studied. The results showed that daily rainfall in both climates can be viewed as the result of a multiplicative cascade process fo

The aim of the present study was to determine the pollution load originating from storm water on Lake Vaxjosjon. Each year about 1,050,000 m3 of storm water are discharged into the lake. Storm water represents a substantial pollution source for the lake and therefore also a main reason for the hypertrophic conditions in the lake. In order to evaluate the effects of the discharged storm water on th

Fifty-two double-ring infiltrometer tests, performed in a small, partly urbanized catchment in northern Tunisia are analyzed. Spatial variability is characterized by use of cross-correlation functions. Spatial patterns of infiltration properties are shown to be governed by geomorphology and occurring vegetation. Different geomorphological zones and zones with equal density of vegetation tend to be

A model based on the two‐dimensional stochastic advection‐diffusion equation is developed to forecast properties of individual rain cells in urban areas such as speed and spatial rainfall intensity. Two different modeling approaches are employed, and examples of the results are given. The first approach involves a Gaussian distribution as an analytic solution to the advection‐diffusion equation, w

Under arid natural conditions, soil water content governs and limits the number and size of perennial plant species. Thus, plant-available soil water is the main constraint for sustainable control of desert encroachment. To evaluate possibilities for re-vegetation of bare sand surfaces, soil water and temperature patterns for typical sand dunes in a desert climate were investigated. Bare and veget

Semiarid Tunisia is characterized by agricultural production that is delimited by water availability and degraded soil. This situation is exacerbated by human pressure and the negative effects of climate change. To improve the knowledge of long-term (1980 to 2020) drivers for Land Use and Land Cover (LULC) changes, we investigated the semiarid Rihana region in central Tunisia. A new approach invol

The spatial distribution of major ion concentration limits the predictability of solute sport processes in field soils. Therefore, it is important to analyze solute transport with chemical reactions based on results obtained from field soils and numerical simulation. A simulation model with cation-exchange reactions was developed and applied to solute-transport analysis of an undisturbed field soi

Temporal and spatial variability of soil water content on mainly two different scales is visualized by means of correlation analyses. The soil water data were collected at seven sites for a period of about ten years. The spatial variability of soil water in the unsaturated zone is illustrated and discussed from the aspects of interdepth, intersite and temporal changes respectively. The results in

Studies dealing with stormwater pollution transport on a local scale have been carried out in Sweden since the middle of the 1970s. 1-7 However, so far no investigation has aimed at determining the importance of stormwater pollution on a larger scale, involving a region or a part of the country. Such studies would provide the necessary background information for (1) developing a regional (nationwi

A study aiming at the estimation of yearly volumes of CSO and yearly quantities of pollution load from CSO had been carried out in the city of Malmo, Sweden. Storm Water Management Model was used both to simulate single CSO events and for continuous simulation. The results from these simulations were compared with actual measurements.-from Authors

There is a need to improve rainfall forecasting capabilities for small ungaged urban catchments to reduce flooding hazards and pollution release. For this purpose, information is required on small-scale and short-term convective cell behavior. We use a two-dimensional stochastic advection-diffusion model to parameterize the space-time rainfall intensity from convective rainfall. The rainfall inten

Fluvial floods are commonly studied as an occurrence at the level of a specific basin and are speculated to be closely related to the basin's morphometry. It is possible to identify and rank sub-basins based on how susceptible they are to fluvial flooding events using morphometric criteria. However, one of the key causes that triggers fluvial flooding is the increase in precipitation extremes and

Sivakumar et al. (2000a), by employing the correlation dimension method, provided preliminary evidence of the existence of chaos in the monthly rainfall-runoff process at the Göta basin in Sweden. The present study verifies and supports the earlier results and strengthens such evidence. The study analyses the monthly rainfall, runoff and runoff coefficient series using the nonlinear prediction met

Problems with increasing heavy metal contents in natural waters are becoming a global issue. At the same time, improved methods for water treatment are becoming increasingly important. In this context, natural zeolites can be used to purify polluted water. In this paper, we investigated how the adsorption capacity of natural zeolites can be improved. Natural zeolites from the Shankanay district, A