Carbon, nitrogen and heavy metal dynamics in long-term wastewater irrigated Mexican soils.
In column experiments of Mexican wastewater irrigated soils the effects of changing water quality (untreated = UT, primary = PT and tertiary treated = TT wastewater) on carbon, nitrogen and heavy metal dynamics were investigated. In the column effluents the nitrate concentrations varied between 141-683 mg l-1. The total amount of leached TOC decreased in the order UT > PT > TT. Outflow concentrations of Pb ranged from 31.6-166.5 micrograms l-1 and of Cu from 31.2-146.8 micrograms l-1. Irrigation water quality influenced the Pb but not the Cu efflux. Cu seemed to be co-transported with TOC by preferential flow whereas there was no correlation of Pb and TOC concentrations in the effluents. The possibility of Pb transport through preferential flow paths is discussed.
Herre
A
A
Institute of Soil Science and Land Evaluation, Hohenheim University, Stuttgart, Germany.
Siebe
C
C
Kaupenjohann
M
M
D000383:Agriculture; D002244:Carbon / Q000032:analysis*; D003247:Conservation of Natural Resources; D006801:Humans; D019216:Metals, Heavy / Q000032:analysis*; D008800:Mexico; D009584:Nitrogen / Q000032:analysis*; D012722:Sewage / Q000032:analysis*; D012989:Soil Pollutants / Q000032:analysis*; D018508:Water Purification
D019216:Metals, Heavy; D012722:Sewage; D012989:Soil Pollutants; D002244:Carbon; D009584:Nitrogen