Irrigated zones

It also gives a good description of important hydrodynamic features such as the existence of non irrigated zones and the liquid velocity distribution in the irrigated ones. The few examples analyzed above indicate also that the postulated model can describe many transport processes. In fact, the list of reported applications is not limitative. 

This lattice representation provides a powerfull tool for numerical simulations using e.g. Monte Carlo methods. While somewhat out of the scope of this paper, these numerical simulations are interesting to interpret because they evidence the type of liquid flow properties it is possible to account for by means of the percolation concept. Figure 10 illustrates a typical result of these simulations. It represents for different cases, the distribution of irrigated zones in a cross section of the packing. The black squares show the intersections of the liquid flow paths with the cross section. 

Contaminated groundwater (leachate) should be kept below the root growth zone. Only rainwater or clean irrigation water should meet the needs of plants. 

Except for zones below the level of permanent ground water where the environment is water-saturated, and for zones of dry surface sand, continual variation may be expected to occur in the water content of soils. This is usually dependent on rainfall, snow, flooding and such climatic influences, though irrigation practices in many agricultural areas influence water content and hence the corrosion rates. 

Shalhevet J (1973) Irrigation with saline water. Chapter VI.I, Arid zone irrigation. Springer, Berlin, 433p... 

The so-called splash zone , the head space in a mixing vessel above the bulk phase of product, may be irrigated with condensation water, washing less persistent biocides away and allowing microbial growth to occur in this area. 

Condensation > irrigates splash zone - biocide washed away... 

A schematic of a bioventing installation, including a system for the addition of water and nutrients, is depicted in Figure 14.4. When the contaminated zone is near the surface and the soil is sufficiently permeable, the addition of water, together with dissolved nutrients, can be carried out using a simple surface irrigation system. When the contamination is located at lower horizons, an underground infiltration system or a network of wells may be more appropriate. 

Banin A., Navrot J., Noi Y., Yoles D. Accumulation of heavy metals in arid-zone soils irrigated with treated sewage effluents and their uptake by rhodes grass. J Environ Qual 1981 10 536-540. 

However, as far as we know, the distribution of LAS biodegradation intermediates according to depth in the sediment column has been determined only in marine sediments [58]. This study was performed in a saltmarsh channel (Sancti Petri Channel, Cadiz Bay, Spain), receiving untreated urban wastewater effluents. In this zone the benthic organisms are very scarce [59], and the capacity for irrigation of... 

Diffusion and dispersion occur in both the liquid and vapor phases. In the vadose zone, liquid-phase dispersion is a major factor following a rainfall (or irrigation) event. Dispersion of vapor phase can also occur. Driving forces for vapor and dispersion are gravity and variations of atmospheric pressure (or SVE/air sparge operations). 

Skaggs, T.H., Poss, J.A., Shouse, P.J., Grieve, C.M. Irrigating Forage Crops with Saline Waters 1. Volumetric Lysimeter Studies. Vadose Zone J. 5(3), 815-823 (2006a)... 

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