?url_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Adc&rft.title=Soil+quality+aspects+of+humid+sandy+loams+as+influenced+by+organic+and+conventional+long-term+management&rft.creator=Schj%C3%83%C2%B8nning%2C+Per&rft.creator=Elmholt%2C+Susanne&rft.creator=Munkholm%2C+Lars+J.&rft.creator=Debosz%2C+Kasia&rft.subject=+Composting+and+manuring&rft.subject=+Soil+quality&rft.subject=+Crop+combinations+and+interactions&rft.subject=+Soil+tillage&rft.subject=+Farming+Systems&rft.subject=+Soil+biology&rft.description=The+development+of+low-input+farming+systems+requires+knowledge+of+the+extent+to+which+management+characteristics+influence+the+soil+as+a+habitat+for+micro-organisms+and+a+medium+for+plant+growth.+This+paper+presents+a+study+of+long-term+effects+of+organically+and+conventionally+cultivated+systems+on+a+range+of+soil+physical%2C+chemical+and+biological+characteristics+in+Denmark.+Seven+soils+were+included%2C+falling+into+three+groups+(I%C3%82%C2%AFIII).+Each+group+consists+of+an+organically+managed+soil+(Org)+referenced+by+one+or+two+conventionally+managed+soils+(Conv)+with+the+same+soil+type+(sandy+loam)+and+pedological+history.+All+organically+managed+soils+were+dairy+farm+soils+(H)%2C+which+had+been+organically+managed+for+46%2C+47+and+40+years%2C+respectively.+They+had+forage+crop+rotations+and+received+animal+manure.+The+conventional+soils+were+either+dairy+farm+soils+or+soils+grown+to+annual+cash+crops+(P).+Undisturbed+core+samples+were+used+for+assessing+dry+bulk+density+and+water+retention.+Undisturbed+cubic+samples+were+used+for+assessing+wet+stability+of+macro-aggregates%2C+clay+dispersibility%2C+microbial+biomass+C%2C+-glucosidase+activity%2C+ergosterol%2C+and+the+abundance+of+different+groups+of+fungi.+Penetration+resistance+and+ease+of+soil+fragmentation+were+measured+in+the+field.+The+quantifying+methods+were+supplemented+by+a+visual+inspection+of+soil+structure+of+the+top+30+cm+soil+in+the+field.+Irrespective+of+agricultural+system%2C+the+use+of+tractors+and+heavy+machinery+had+caused+compaction+of+the+subsoil+in+the+form+of+a+dense+pan+below+ploughing+depth.+In+group+I%2C+the+H-soils+were+heavily+trafficked+and+this+overshadowed+the+long-term+effects+of+the+diversified+crop+rotations+and+animal+manure+applications+on+the+physical+parameters.+Generally%2C+the+results+highlight+the+paramount+influence+of+soil+tillage+and+traffic+in+agriculture.+Further%2C+the+results+confirm+the+positive+effects+of+organic+manures+and+diversified+crop+rotations+on+soil+quality+aspects.+Microbial+biomass+C+was+found+to+be+higher+in+organically+than+in+conventionally+managed+dairy+farm+soils%2C+and+appeared+to+correlate+linearly+to+the+volume+of+0.2%C3%82%C2%AF3.0+m+pores+(%60protective'+pore+space).+The+simple+model+did%2C+however%2C+not+explain+a+lower+microbial+biomass+for+two+soils+dressed+only+with+synthetic+fertilisers.+The+results+further+indicated+that+the+contribution+of+the+different+biotic+mechanisms+responsible+for+macro-aggregation+varied+from+soil+to+soil.+The+results+revealed+promising+correlations+between+quantitative+scientific+laboratory+methods+and+descriptive+methods+in+the+field.&rft.date=2002-03&rft.type=Journal+paper&rft.type=NonPeerReviewed&rft.format=application%2Fpdf&rft.identifier=http%3A%2F%2Forgprints.org%2F40%2F1%2Fmanus1.pdf&rft.identifier=Schj%C3%83%C2%B8nning%2C+Per%3B+Elmholt%2C+Susanne%3B+Munkholm%2C+Lars+J.+and+Debosz%2C+Kasia+(2002)+Soil+quality+aspects+of+humid+sandy+loams+as+influenced+by+organic+and+conventional+long-term+management.+Agriculture%2C+Ecosystems+%26+Environment%2C+88+(3)%2C+pp.+195-214.+**&rft.relation=http%3A%2F%2Forgprints.org%2F40%2F