Soil organic amendments(OAs)are used to replenish carbon(C)and nutrients in the soil to prevent its degradation and increase its fertility.While soil can be an important C sink,it can also release significant amounts ...Soil organic amendments(OAs)are used to replenish carbon(C)and nutrients in the soil to prevent its degradation and increase its fertility.While soil can be an important C sink,it can also release significant amounts of greenhouse gases(GHGs).Different OA pretreatment technologies indirectly affect soil aggregate formation and C stabilization even when the same initial substrate is used.However,little is known about the long-term effect of OA pretreatment on the soil C and nitrogen(N)associated with macroaggregates,which are known to disintegrate faster than microaggregates.In this study,we studied the effect of OA pretreatment on soil C and N in relation to aggregate formation and GHG emissions using five differently pretreated OAs from the same original OA,i.e.,composted,digested,and fermented OA,a 1:1 mix of the composted and fermented OAs,and the unpretreated original OA.We monitored the changes in a soil column experiment after 6 and 12 months of incubation.Our results indicated that OA pretreatment indirectly affected GHG emissions from soil.The composted and mixed OAs released less GHGs(i.e.,carbon dioxide,nitrous oxide,and methane)but had no positive impact on macroaggregates,while the digested OA induced long-lasting macroaggregation and occluded particulate organic matter formation,emitting intermediate levels of GHGs.The unpretreated OA exhibited the highest GHG emissions,similar to the fermented OA,albeit without benefiting macroaggregation.These demonstrated that OA pretreatment had a long-lasting indirect effect on soil C and N,influencing total GHG emissions,nitrous oxide formation mechanisms,and soil macroaggregate formation.展开更多
基金funded by the Dutch Ministry of Economic Affairs and Climate Policy,the European Union Regional Development Fund,the City of Leeuwarden,the Province of Fryslân,the Northern Netherlands Provinces and The Netherlands Organization for Scientific Research.Wetsus also coordinates the WaterSEED project,which received funding from the European Union's Horizon 2020 research and innovation program under the Marie Sklodowska-Curie grant agreement(No.665874)。
文摘Soil organic amendments(OAs)are used to replenish carbon(C)and nutrients in the soil to prevent its degradation and increase its fertility.While soil can be an important C sink,it can also release significant amounts of greenhouse gases(GHGs).Different OA pretreatment technologies indirectly affect soil aggregate formation and C stabilization even when the same initial substrate is used.However,little is known about the long-term effect of OA pretreatment on the soil C and nitrogen(N)associated with macroaggregates,which are known to disintegrate faster than microaggregates.In this study,we studied the effect of OA pretreatment on soil C and N in relation to aggregate formation and GHG emissions using five differently pretreated OAs from the same original OA,i.e.,composted,digested,and fermented OA,a 1:1 mix of the composted and fermented OAs,and the unpretreated original OA.We monitored the changes in a soil column experiment after 6 and 12 months of incubation.Our results indicated that OA pretreatment indirectly affected GHG emissions from soil.The composted and mixed OAs released less GHGs(i.e.,carbon dioxide,nitrous oxide,and methane)but had no positive impact on macroaggregates,while the digested OA induced long-lasting macroaggregation and occluded particulate organic matter formation,emitting intermediate levels of GHGs.The unpretreated OA exhibited the highest GHG emissions,similar to the fermented OA,albeit without benefiting macroaggregation.These demonstrated that OA pretreatment had a long-lasting indirect effect on soil C and N,influencing total GHG emissions,nitrous oxide formation mechanisms,and soil macroaggregate formation.
