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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
This paper presents a method to use pattern recognition in the analysis of soil water dynamics in time and space simultaneously. Space‐time correlation structures are generated by use of a numerical model for the one‐dimensional unsaturated flow equation. By applying the method to various soil parameter combinations (unsaturated hydraulic conductivity and dispersion coefficient) and length of infi
Sewage sludge amendment of soils leads to an increase in soil fertility, but may induce heterogeneities not initially present in the soil. Spatial variation of soil organic carbon (C) and nitrogen (N) was studied in a heavy clay soil after a sewage sludge application and NPK-treatment (nitrogen, phosphorus, and potassium) using geostatistical approaches. In total, 314 soil samples were taken on tw
Two-year series of 1-min rainfall intensities observed by rain gages at six differrent points are analyzed to obtain information about the fractal behavior of the rainfall distribution in time. First, the rainfall time series are investigated using a monodimensional fractal approach (simple scaling) by calculating the box and correlation dimensions, respectively. The results indicate scaling but w
This study aims at investigating the occurrence and characteristics of drought patterns by analyzing a 238-year long monthly precipitation time sequence observed at Lund in Sweden using an ordinary Kalman filter (OKF) and an adaptive Kalman filter (AKF). The OKF identifies the periods (in the time sequence) with anomalous precipitation by comparing the observed and average precipitation patterns.
Direkta saneringskostnader efter en kärnteknisk olycka för ett typiskt svenskt bostadsområde med enfamiljshus uppskattades genom att skicka ett underlag liknande en offertförfrågan till en entreprenör med verksamhet riktad mot bl.a. konventionell sanering av fastigheter. Det fiktiva uppdraget omfattade en rad saneringsmetoder som tidigare beskrivits i olika handböcker för sanering av radioaktiv be
Presents a two-dimensional stochastic convection-diffusion model for use in real-time prediction of the space-time rainfall structure in urban areas. The model is used to parameterize the rainfall intensity from individual rain cells. Especially, we are interested to quantify the rainfall intensity resulting from different separable components of the rain cell. This is done by a Lagrangian approac
