Nitrous oxide fluxes from Malagasy agricultural soils

Texture and organic carbon contents do not impact amount of carbon protected in Malagasy soils

“…extractable in ammonium oxalate (Fe OX ), respectively (e.g. Chapuis-Lardy et al, 2009). As soil Al or Fe oxides are generally associated with clay+fi ne silt fraction contents (Zinn et al, 2007), our results showed a correlation of clay+fi ne silt fraction with SOC ( Figure 1A) and with macroaggregates ( Figure 1F).…”

Soil N2O emissions in French Guiana after the conversion of tropical forest to agriculture with the chop-and-mulch method

“…For example, in the humid tropics of Costa Rica, Weitz et al (2001) measured for loam soils with high water retention capacity, average N 2 O fluxes of 2.5 AE 1.7 (non-fertilized plots) and 8.5 AE 10.3 g N ha À1 day À1 (fertilized plots). In Madagascar, under altitude tropical climate, Chapuis-Lardy et al (2009) reported low N 2 O fluxes, from 0 to 8.8 g N ha À1 day À1 , for agricultural Ferralsol. After the chop-and-mulch method was used on a 15-year-old fallow area on acidic sandy soils in eastern Amazonia, Davidson et al (2008a) estimated that the N 2 O emissions were equal to 0.4 kg N ha À1 for the pre-planting period (60 days) + 2.9 kg N ha À1 for a 480-day cropping cycle (rotation maize + cassava with 90 kg N ha À1 input the first year/leguminous trees); i.e., 6.1 g N ha À1 day À1 for these two periods.…”

Relationships between soil physico-chemical, chemical and biological properties in a soil amended with spent mushroom substrate

“…The main reasons for enhanced N 2 O emissions from cultivated soils are increased N inputs by mineral fertilisers and animal wastes (IPCC, 1996(IPCC, , 2007. N 2 O is produced during numerous nitrogen transformations in soils, but on most occasions denitrification and nitrification are the main sources (Chapuis-Lardy et al, 2009).…”