Long-term accumulation and material balance of organic matter in the soil of an effluent infiltration basin

Soil cultivation for enhanced wastewater infiltration in soil aquifer treatment (SAT)

“…Long-term reduction in infiltration rate has been previously observed (Lin et al, 2008;Nadav et al, 2010;Gilboa et al, 2011). The long-term application of TWW in the infiltration basins of the Shafdan WWTP exhibited OM accumulation in the top soil layer.…”

“…They ascribed this decrease to the easily decomposed substances increasing microbial activity, a process which has been defined as priming effect. In the long run, equilibrium occurs between accumulation and decomposition of OM in the top soil layer and OM content remains relatively constant (Lin et al, 2008). However, increased OM accumulation during the winter and reduced values during the summer in the top soil layer have been reported by Chen et al (2009) andNadav et al (2010) in commercial TWWinfiltration basins.…”

“…During TWW infiltration through the soil layers, the dissolved organic carbon concentration is reduced by 70-90% (Lin et al, 2008). Polysaccharides, proteins and humic substances (HSs) are removed to a great extent during the TWW percolation through the soil under anoxic conditions (Amy and Drewes, 2007).…”

“…Polysaccharides, proteins and humic substances (HSs) are removed to a great extent during the TWW percolation through the soil under anoxic conditions (Amy and Drewes, 2007). The top soil layer (0-15 cm) of the infiltration basin retains most of the particulate organic matter (OM) originating from the TWW, resulting in a soil OM increase of about 800% (Lin et al, 2008). Even in less extensive TWW loadings, accumulation of OM in the top soil layer as a consequence of TWW irrigation in comparison to freshwater (FW) irrigation has been reported by several investigators (Tarchitzky et al, 2007;Jueschke et al, 2008).…”

Impact of long-term reclaimed wastewater irrigation on agricultural soils: A preliminary assessment

“…For instance, contents of organic matter and available nutrients (e.g. phosphorus, potassium, nitrogen) were elevated, thereby enhanced the fertility and productivity of effluent-irrigated soils [8][9][10]. However, as a result of long-term irrigation with reclaimed wastewater, many questions have been raised with regards to long-term gradual changes in soil physical and chemical properties, and accumulation of environmental contaminants in soils of the irrigated area, which may consequently degrade the soil quality and elevate the contaminants levels in plants.…”