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Field variability of element concentrations in wheat and soil
Field variability of element concentrations in crops is important to consider for nutrient application as well as for evaluation of environmental hazards. The paper gives an analysis of spatially sampled wheat plant tissue in the field to determine spatial properties of 20 elements for a partly sludge-applied agricultural soil in northern Tunisia. A comparison is made with the spatial variability
Lateral bromide distribution in a vertic clay soil
In order to control the transport of toxic elements, dissolved salts, and nutrients in agricultural areas, information on the spatial variability of field-scale transport properties is needed. To evaluate this for an unsaturated layered clayey soil, tracer tests were conducted at the Cherfech experimental field research station in Tunisia. Bromide-tagged water was infiltrated under ponding conditi
Some Eulerian and Lagrangian statistical properties of rainfall at small space-time scales
Management of urban hydrological systems requires a knowledge of short-term and small-scale rainfall properties. Small catchment areas, dense building structures, a high degree of impermeable areas, and resulting rapid runoff, mean that the properties of individual rain cells are important considerations. Accordingly, this paper characterizes mainly spatial rainfall properties on a scale suitable
Alternate Partial Root-Zone Surface Drip Irrigation for Tomato : Hydrus-2D
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The infiltration equations according to Horton and Philip are applied to 52 double-ring infiltrometer tests performed in a small semiarid catchment in northern Tunisia. Spatial variability in infiltration properties is analysed as regards the coefficients of the two equations. Different geomorphological zones display different infiltration characteristics even if there is large variability within
Transport and sedimentation of pollutants in a river reach : A chemical mass balance approach
The River Höje in the south of Sweden is a typical receiving water for urban and rural runoff. Mass balance calculations over a 17‐month period indicate that pollutants are retained in the sediments of the investigated 5‐km‐long reach of the stream (90 tons of biochemical oxygen demand (BOD7), 850 tons of chloride, 2.1 tons of copper, 3.2 tons of zinc, and 1.0 ton of lead). Other pollutants such a
Rainfall estimation in the Chikugo River Basin by Atmospheric downscaling using artificial networks
For the proper water resources management of the Chikugo River basin, the prediction of both drought and heavy rainfall needs to be carried out by the conventional and engineering method which can be useful to for the practitioners who work on the water resources management and flood control. A relatively simple and efficient way to estimate local and regional rainfall, as well as other hydrometeo
Plot-scale solute transport in a semiarid agricultural soil
Parameterization of rain cell properties using an advection-diffusion model and rain gage data
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 Transport in Different Drip-Irrigated Soil Types with Potato Crop
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
Temporal rainfall disaggregration based on scaling properties
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
Predicting Soil Saturated Water Conductivity Using Pedo-Transfer Functions for Rocky Mountain Forests in Northern China
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
Soil water, soil chemical and crop variations in a clay soil
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
Multifractal properties of daily rainfall in two different climates
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 effects of storm water on Lake Vaxjosjon
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
Spatial variability of infiltration in a semi-arid environment
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
Real‐time rainfall prediction at small space‐time scales using a two‐dimensional stochastic advection‐diffusion model
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
Soil water and temperature patterns in an arid desert dune sand
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
Analysis of Four Decades of Land Use and Land Cover Change in Semiarid Tunisia Using Google Earth Engine
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