Effect of urban waste compost application on soil near-saturated hydraulic conductivity.
Compost application tends to increase soil fertility and is likely to modify soil hydrodynamic properties by acting on soil structural porosity. Two composts, a municipal solid waste compost (MSW) and a co-compost of green wastes and sewage sludge (SGW), have been applied every other year for 6 yr to cultivated plots located on a silt loam soil in the Parisian Basin, France. Four soil zones were defined in the topsoil after plowing: the plowpan located at the base of the plowed layer, compacted (Delta) or noncompacted (Gamma) zones located within the plowed layer, and interfurrows created by plowing and containing a large quantity of crop residues together with the recently-applied compost. To assess the effect of compost application on the near-saturated soil hydraulic conductivity, infiltration rates were measured using a tension disc infiltrometer at three water pressure potentials -0.6, -0.2, and -0.05 kPa in the various zones of the soil profile. Compost addition decreased K((sat)) in the interfurrows after plowing by almost one order of magnitude with average values of 5.6 x 10(-5) m.s(-1) in the MSW plot and 4.1 x 10(-5) m.s(-1) in the SGW plot, against 2.2 x 10(-4) m.s(-1) in the control plot. This effect had disappeared 6 mo after plowing when the average K((sat)) in the control plot had decreased to 1.9 x 10(-5) m.s(-1) while that in the compost-amended plots remained stable.
Schneider
S
S
UMR INRA/AgroParisTech Environnement et Grandes Cultures, 78850 Thiverval-Grignon, France. sebastien.schneider@sckcen.be
Coquet
Y
Y
Vachier
P
P
Labat
C
C
Roger-Estrade
J
J
Benoit
P
P
Pot
V
V
Houot
S
S
D002244:Carbon / Q000032:analysis; D009584:Nitrogen / Q000032:analysis; D009930:Organic Chemicals / Q000032:analysis; D016062:Porosity; D012639:Seeds; D012722:Sewage / Q000737:chemistry*; D012987:Soil / Q000032:analysis*; D014867:Water / Q000032:analysis*
D009930:Organic Chemicals; D012722:Sewage; D012987:Soil; D014867:Water; D002244:Carbon; D009584:Nitrogen