Effect of zeolite application on potassium release in sandy soils amended with municipal compost

Abstract

A B S T R A C TThe use of compost in enhancing organic carbon content and aggregation in soil has been widely studied in the last decades. Recently, compost is used in new environmental applications for the remediation of both contaminated groundwater and soil. However, compost addition increases by 10 orders of magnitude the soil electrical conductivity and the nutrient content such as potassium. Subsequently, nutrient leaching in groundwater may increase water salinity. The present study investigates the effect of zeolite application on potassium release in sandy soils amended with municipal compost. Kinetic experiments show that zeolite addition in soil-compost mixtures have no effect on potassium desorption rate while it results in an 18-fold increase in bio-available potassium. Column tests show that zeolite application results up to six times decrease in total potassium leaching. Experimental results show high potassium affinity for the mixture soil-compost-zeolite in pH > 7, which is of paramount importance, considering that soils in southern Europe (Italy, Spain, south France, Albania and Greece) exhibit slightly alkaline pH in most cases. The findings of this study may be also used to predict the potential of groundwater contamination in agricultural areas as well as during the implementation of preventive measures.

Synthesis of Zeolites from Greek Fly Ash and Assessment of Their Copper Removal Capacity

“…Zeolites may also be used to remove inorganic and organic air pollutants, including nitrogen oxides (NOx) and volatile organic compounds (VOCs) [22][23][24]. Finally, they can be used for the removal, fixation, and control of contaminants and transport of nutrients in soils and sediments [25][26][27][28].…”

Phosphorus and potassium recovery from anaerobically digested olive mill wastewater using modified zeolite, fly ash and zeolitic fly ash: a comparative study

“…3(b)). In any case, the enhanced concentration of exchangeable and plant‐available K in both adsorbents is a beneficial property, since K‐loaded zeolites can be used as slow‐release fertilizers, able to reduce the leaching of K in soils or soilless potting media compared to conventional fertilizers 84,85 …”

Sustainable Agricultural Practices-Impact on Soil Quality and Plant Health

“…The losses of K + by surface runoff and groundwater leaching can be reduced by supplementing the zeolites as slow-release fertilizer [108]. For example, the application of zeolites in municipal compost to investigate the K + release pattern resulted in six times less leaching loss from the zeolitic compost as compared to normal compost [109]. Additionally, Williams and Nelson [110] observed that in a soil-less medium K + saturated clinoptilolite recorded 23% less leaching of K + over-controlled control substrate.…”

“…Additionally, Williams and Nelson [110] observed that in a soil-less medium K + saturated clinoptilolite recorded 23% less leaching of K + over-controlled control substrate. Moraetis et al [109] reported that there was 18-fold increase in bioavailable K when zeolites were added through kinetic experiment to the soil-compost mixture, suggesting high potassium affinity in the soilcompost-zeolite mixture. Zeolite is considered as nano-enhanced green application as it adsorbs molecules at relatively low pressure [111,112].…”