L. Beyer et al., SOIL ORGANIC-MATTER COMPOSITION AND PESTICIDE BONDING IN SANDY SOILS IN RELATION TO GROUNDWATER PROTECTION IN THE NORTHWEST GERMAN LOWER PLAIN, Biology and fertility of soils, 23(3), 1996, pp. 266-272
In sandy gleyic soils with a low groundwater table under arboriculture
in Northwest Germany, a wide variation of groundwater pollution by pe
sticides has been observed. We therefore examined data on microbial ac
tivity and soil organic matter composition by wet chemistry, cross-pol
arization magic-angle spinning and C-13 nuclear magnetic resonance, an
d pyrolysis-field ionization mass spectromy. However, neither microbia
l activity nor the soil organic matter composition of cultivated tapso
ils explained the differences in xenobiotic leaching into the groundwa
ter Data from Anthrosols suggested that these soils oc have a higher c
apacity for pesticide bonding because of high amounts of aromatic and
carboxylic C moieties in the soil organic matter. However, despite the
same pesticide inputs and lime of application, the leached output fro
m these soils was higher than that from the Podzols. Initial data from
subsoil investigations suggest that the presence of a spodic horizon
most likely reduces groundwater pollution by pesticides. Studies to as
sess fixation capacity and desorption kinetics in Bh horison seem warr
anted.