Nutrient leaching from soil amended with apple waste

Abstract

-Among the possibilities for disposing of overproduction of apple, land application is flexible and inexpensive. Six soil columns receiving 0, 200 or 500 Mg of apple waste⋅ha -1 were studied in laboratory experiments with various irrigation depths and timing, and alternate irrigated and drying periods. Leaching solutions were collected at different times for chemical analyses. Organic matter input stimulated microbial activity that used O 2 and released CO 2 , then reduction occurred. Major cations like Ca 2+ , Mg 2+ , and K + involved in mineral dissolution or soil solution exchange were released. High N immobilization and possibly denitrification occurred, organic C was leached, while decreasing redox potential led to Mn dissolution and sulfate reduction. The reoxidation of the soil during drying helped to restore the soil to a condition which pollutes less. Quantities of apple waste deposition less than 200 Mg⋅ha -1 are recommended to minimize environmental damage.

Impact of pig slurry and green waste compost application on heavy metal exchangeable fractions in tropical soils

“…Organic waste amendments can, for instance, increase the quantity of soil soluble OM that is able to complex HM (Stevenson, 1994) and the mobility of these complexes in the aqueous phase, thus facilitating their transport to the deep unsaturated zone and water table (Xue et al, 2003). Moreover, massive organic waste inputs can create reducing conditions (de Cockborne et al, 1999;de Cockborne et al, 2001;Doelsch et al, 2009), which could markedly alter HM speciation, especially the exchangeable fractions (Quantin et al, 2002). Several studies have thus focused on the impact of the mineralization of various organic wastes (compost, slurry, dung, manure) on HM speciation patterns during incubation experiments.…”

Assessing denitrification and N leaching in a field with organic amendments

“…Several researchers [8][9][10][11][12][13][14][15][16][17][18][19][20][21][22][23] ( Table 1) have tested N immobilization of organic materials, aiming at (1) maximum N mineralization especially of mulches and cover crops in N-deficient tropical soils, (2) minimum N immobilization in potting materials in horticulture, and (3) maximum/optimum N immobilization reducing N losses to groundwater and air, especially in high-input agriculture. For our study we chose to use paper pulp, because together with straw it is abundantly available, whereas the range of immobilization capacity of woody materials seems to be much higher than of straw.…”