A greenhouse study was carried out to determine N, P, K, Ca and Mg leaching as well as water uptake in tomato growing on three different substrates. The assumption that various physicochemical ...properties of growing media can affect plant water uptake and nutrients absorption was confirmed. The same fertigation management significantly affected amounts of drained nutrients (327-373 g m-2) and plant water uptake (866-911 L m-2) between tested substrates.
The primary objective of this study was to determine the best irrigation and fertigation practice for tomato crop (Lycopersicon esculentum Mill.) in order to achieve highest yield with maximum water ...use efficiency (WUE). The field experiments were conducted during the period of May to September in 2002, 2003 and 2004. Five experimental treatments tested in this study included the following: the first three treatments (T1, T2, and T3) included a combination of drip irrigation and fertigation, treatment four (T4) included drip irrigation, but with conventional application of fertilizer, and the fifth treatment, (T5), included furrow irrigation practice with conventional application of fertilizer. The results of this study show that the drip fertigation treatments (T1, T2, and T3) gave significantly higher tomato yields in comparison with treatments T4 and T5, almost 24% and 39%. During three years of research treatments under drip fertigation showed almost 28% more water use efficiency in comparison with the treatment with conventional application of fertilizer and drip irrigation and 87% more than the treatment with furrow irrigation and conventional application of fertilizer. So, it is clear that the drip fertigation led to an increased yield, indicating enhanced water use efficiency.
The present study analyses the effects of high copper concentrations on its mobility in the soils from the wine-growing regions of the Northwestern Croatia. The aims of this study were to determine ...the copper distribution in vineyard soils by single extraction procedures, and to relate the total, mobile and mobilisable copper content to several chemical soil characteristics using multiple regression analysis. The total Cu concentrations were determined by an aqua regia procedure. Two other methods were used for evaluating soil available copper: DTPA extraction and calcium chloride extraction. The physical and chemical characteristics (texture, organic C, pH, CaCO3, total P, CEC) were determined as well. Both DTPA- and CaCl2-extractable copper were largely explained by the total copper contents, and they were also highly correlated to each other. It was found that the DTPA-extractable copper decreased with increasing cation exchange capacity, but concentrations of CaCl2-extractable copper mainly depend on pH.
A two-year greenhouse study was performed to determine the possibility of estimating the transpiration rate in hydroponically grown tomato on the basis of climate parameters. Transpiration rate, ...determined by the water balance method on different substrates, was compared to the transpiration rate calculated using the Penman Monteith equation. Regression analysis of the comparison of two different approaches to water consumption determination confirmed that the transpiration rate of greenhouse grown tomato for the studied area can be estimated with high accuracy (R2 > 0.95).
Up to 20% of irrigated arable land in arid and semi-arid regions worldwide is salt-affected. The problem of salt-affected soils is also present in the Croatian Mediterranean coastal region where ...seawater intrudes through porous media into calcareous aquifers, mixes with freshwater and salinizes both ground and surface waters. Climatic conditions enable continuous growing of several crops throughout a year, but increasing demand for irrigation water forces the growers to utilize water of poor quality. In 2005, the effect of rising salinity levels (control, 4, 6, and 8 dS m-1) on strawberry vegetative growth and fruit yield was studied in a greenhouse experiment. Salinity treatments had a negative effect on total fresh fruit yield (29-59%), total number of fruits (24-45%), fruit size, as well as on the number of runners (23-86%) and the length of the longest runner (1.3-2.6 times). Furthermore, NaCl salinity stress accelerated leaf senescence and reduced the strawberry growing period by 12-22 days.
Large numbers of numerical models are nowadays available for the description of physical and chemical processes affecting water flow and solute transport in soil vadose zone. This chapter explains ...basic principles of water flow and solute transport modelling in soil vadose (variably saturated) zone and some of the most important processes present in it. First part deals with water dynamics in the soil, that is, soil water content, pressure head, soil porosity, and water flow. Also, some of the measurement techniques used to estimate water dynamics in soil are explained. Water retention curve and soil hydraulic properties needed for modelling are briefly discussed with the explanation of basic (i.e. most commonly used) hydraulic relationship in soil (van Genuchten equation) and water flow (Richards equation) approaches. Second part includes solute transport description in vadose zone, including processes such as advection, diffusion, dispersion, and adsorption. Basic advection‐dispersion equation is explained and also the implementation of boundary and initial conditions in the numerical model. Preferential flow is shortly discussed with the basic principles behind its occurrence and modelling in the soil vadose zone. One real case one‐dimensional (1D) example of modelling with HYDRUS software is presented in which water flow and nitrate transport is simulated on the lysimeter study. Short overview of the most widely used numerical models for simulating vadose zone processes is also presented, whereas the final part is focused on chemical speciation modelling in relatively homogeneous soil solutions using visual MINTEQ interface.
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