?url_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Adc&rft.title=Bewirtschaftung+von+organochlorbelasteten+B%C3%83%C2%B6den&rft.subject=+Soil&rft.description=State+of+the+Art%3A%0D%0AResidues+of+organochlorine+pesticides+(OCP)+in+soils%2C+such+as+Dieldrin+and+DDT+contaminate+crops%2C+even+though+their+use+was+banned+by+the+European+Union+30+years+ago.+The+aim+of+this+project+is+to+develop+methods+reducing+the+concentration+of+OCP+in+the+edible+parts+of+crops+grown+on+contaminated+soils.+This+will+be+achieved+by+a+two+step+procedure%3A+First+we+will+add+different+organic+carbon+sources+to+the+soil%2C+which+can+lead+to+binding+and+immobilising+of+OCP%2C+resulting+in+reduced+bioavailability+of+OCP.+Second+we+will+select+root+stocks+of+grafted+plants+(i.e.+cucumbers)+with+a+high+capacity+to+exclude+OCP+from+plant+uptake.+Combinations+of+these+two+methods+will+be+evaluated.%0D%0ADefinition+of+the+problem%3A%0D%0ABackground%3A+Organochlorine+pesticides+(OCP)+such+as+Dieldrin+and+DDT+were+applied+world+wide+against+pests+in+horticulture%2C+fruit+and+arable+crops.+Although+OCP+are+forbidden+since+more+than+twenty+years+in+the+European+Union+(EU)%2C+the+highly+persistent+compounds+are+still+detectable+in+soil.+Several+crops+are+known+to+accumulate+OCP+in+edible+parts+up+to+critical+levels.+For+instance+Dieldrin+is+detected+in+high+economic+value+crops+such+as+cucumbers+(Cucurbitaceae)+and+tomatoes+(Solanaceae).+Besides+plant+type+and+climatic+conditions%2C+soil+properties%2C+e.g.+pH+and+soil+organic+carbon+content+influence+the+plant%C3%A2%C2%80%C2%99s+OCP+uptake.+In+particular+in+premium+food+and+feed+stuff+production%2C+such+as+organic+farming+according+to+EU+Regulation+(EEC)+No.+2092%2F91%2C+consumer+expectations+in+safe%2C+high+quality+food+are+extremely+high.+Since+organic+farming+is+prospering+%C3%A2%C2%80%C2%93+more+than+10%25+of+vegetable+production+is+certified+organic+in+Switzerland+%C3%A2%C2%80%C2%93+the+OCP+residues+in+organic+food+stuff+have+become+a+major+issue+for+food+control+authorities.+Enquiries+showed+that+some+of+the+imported+food+from+EU+countries+such+as+pumpkin+seed+and+oil+was+highly+contaminated+with+OCP.+Hence%2C+the+OCP+problem+in+food+stuff+is+expected+to+occur+EU+wide+or+even+world+wide.%0D%0APreliminary+study%3A+Facing+this+problem+we+performed+a+case+study+and+analysed+the+OCP+content+of+15+fields+and+their+grown+fruits+from+the+most+important+Swiss+organic+cucumber+growers.+Two+out+of+these+15+field+soils+revealed+Dieldrin+leading+to+surpassing+of+the+tolerance+level.+It+also+occurred+that+the+whole+crop+yield+from+an+OCP+contaminated+field+was+rejected+by+food+retailers+and+the+crop+had+to+be+ploughed+down.+The+Swiss+organic+label+organisation+has+the+option+in+their+standard+now+to+exclude+polluted+soils+for+production+of+highly+OCP+accumulating+vegetables%2C+but+this+may+severely+affect+the+grower%C3%A2%C2%80%C2%99s+economy.%0D%0AProject+aims+including+target+group%3A%0D%0AObjectives%3A+In+this+project+we+aim+at+developing+sustainable+safe+food+production+on+OCP+contaminated+soils%2C+which+is+economically+and+ecologically+sound.%0D%0A%0D%0AFirst+we+will+perform+an+in-depth+field+survey+on+50+sites+to+assess+the+extent+of+OCP+contamination+on+Swiss+farms.+Soils+and+Cucurbitacea+crops+will+be+analysed+for+OCP.+Cucurbitacea+are+chosen+because+crops+of+this+family+accumulate+strongly+OCP+and+thus+are+suitable+as+indicator+plant.%0D%0A%0D%0ASecond%2C+we+will+develop+strategies+in+bioassays+in+the+glasshouse+to+lower+OCP+uptake+from+the+contaminated+field+soils+through+immobilisation+of+OCP+by+organic+carbon+addition+to+the+soil+and+by+selection+of+OCP+excluder+plant+varieties.%0D%0A%0D%0AThese+experiments+are+organised+as+follows%3A%0D%0Ai)+Test+system+optimization%3A+We+will+optimize+a+previously+used+test+system+for+the+immobilisation+and+exclusion+experiments+(see+below).+We+will+grow+cucumbers+in+OCP+contaminated+field+soils+(little%2C+medium%2C+high)+and+measure+OCP+in+the+growing+cucumbers+in+a+time+course.+As+an+alternative+we+will+use+cress+as+a+test+plant+to+shorten+the+duration+of+the+experiment.+14C-labelled+Dieldrin+will+be+used+to+calculate+fluxes+in+the+soil-plant+system.+Based+on+the+results+of+these+experiments+we+will+decide+which+soil+and+crop+we+will+use+in+the+following+tests+and+when+the+test+plant+will+be+harvested+for+OCP+analyses.%0D%0A%0D%0Aii)+Immobilisation+of+OCP+by+organic+carbon%3A+The+aim+of+these+experiments+is+to+immobilise+OCP+in+the+soil+by+the+addition+of+organic+carbon+to+the+soil.+The+hypothesis+is+that+the+OCP+will+be+bound+by+the+organic+carbon+and+consequently+the+bioavailability+is+expected+to+be+decreased.+Organic+carbon+will+be+added+to+the+soil+in+form+of+compost+or+as+brown+coal+product+(charcoal)+at+three+levels+each.+The+bioavailability+of+OCP+will+be+assessed+by+measuring+these+molecules+in+the+plant+shoot.%0D%0A%0D%0Aiii)+Exclusion+of+OCP+by+crops%3A+The+aim+of+these+experiments+is+to+identify+plant+varieties+with+a+low+OCP+uptake.+Since+cucumbers+are+normally+cultivated+by+grafted+plants+nowadays%2C+where+a+robust+and+vital+root+stock+is+inoculated+by+a+desired+variety%2C+we+will+select+for+OCP+excluder+root+stocks.+For+cucumbers%2C+root+stocks+from+the+groups+of+Cucurbita+moschata+x+C.+maxima%2C+Sicyos+angulatus+and+Cucurbit+ficifolia+are+currently+in+use%2C+but+we+will+test+further+ones+from+the+same+family.+The+root+stocks+and+the+grafted+plants+will+also+be+cultivated+in+contaminated+field+soils+and+OCP+will+be+measured+in+the+plant%C3%A2%C2%80%C2%99s+tissue.+The+most+promising+treatments+from+the+immobilisation+and+the+exclusion+experiments+will+be+applied+in+combination.%0D%0A%0D%0AFinally+we+synthesize+the+results+from+the+field+survey+and+the+glasshouse+experiments+and%2C+including+literature+findings%2C+we+suggest+field+evaluations+of+the+elaborated+strategies+for+safe+food+production+on+OCP+contaminated+soils.+We+already+expect+after+three+project+years+a+high+degree+of+applicability+of+the+strategies%2C+since+this+project+bridges+basic+and+applied+research+and+combines+different+strategies+to+prevent+plant+uptake+of+the+harmful+OCP.%0D%0AMethodology%3A%0D%0AField+survey+of+OCP%2C+OCP+analyses+by+GC-MS+(to+be+adapted)%2C+Bio-assay%2C+plant+grafting%0D%0A%0D%0A&rft.type=Project+description&rft.type=NonPeerReviewed&rft.identifier=%7BProject%7D+Organochlorbelastete+B%C3%83%C2%B6den%3A+Bewirtschaftung+von+organochlorbelasteten+B%C3%83%C2%B6den.+[Safe+food+production+on+soils+contaminated+with+organochlorine+pesticides.]+Runs+2005+-+2008.+Project+Leader(s)%3A+Wyss%2C+Gabriela+and+M%C3%83%C2%A4der%2C+Paul%2C+Research+Institute+of+Organic+Agriculture+(FiBL)%2C+CH-5070+Frick.&rft.relation=http%3A%2F%2Forgprints.org%2F6276%2F