| Title | FATE OF DIURON AND LINURON IN A FIELD LYSIMETER EXPERIMENT |
| Abstract | The environmental fate of herbicides can be studied at different levels: in the lab with disturbed or undisturbed soil columns or in the field with suction cup lysimeters or soil enclosure lysimeters. A field lysimeter experiment with 10 soil enclosures was performed to evaluate the mass balance in different environmental compartments of the phenylurea herbicides diuron [3-(3,4-diclorophenyl)-1,1-dimethylurea] and linuron [3-(3,4-dichlorophenyl)-1-methoxy-1-methylurea]. After application on the agricultural soil, the herbicides were searched for in soil, pore water, and air samples. Soil and water samples were collected at different depths of the soil profile and analyzed to determine residual concentrations of both the parent compounds and of their main transformation products, to verify their persistence and their leaching capacity. Air volatilization was calculated using the theoretical profile shape method. The herbicides were detected only in the surface layer (0-10 cm) of soil. In this layer, diuron was reduced to 50% of its initial concentration at the end or the experiment, while linuron was still 70% present after 245 it. The main metabolites detected were DCPMU [3-(3,4-dichlorophenyl)-1-methylurea] and DCA (3,4-dichloroaniline). In soil pore water, diuron and linuron were detected at depths of 20 and 40 cm, although in very low concentrations. Therefore the leaching of these herbicides was quite low in this experiment. Moreover, volatilization losses were inconsequential. The calculated total mass balance showed a high persistence of linuron and diuron in the soil, a low mobility in soil pore water (less than 0.5% in leachate water), and a negligible volatilization effect. The application of the Pesticide Leaching Model (PELMO) showed similar low mobility of the chemicals in soil and water, but overestimated their volatilization and their degradation to the metabolite DCPMU. In conclusion, the use of soil enclosure lysimeters proved to be a good experimental design for studying mobility and transport processes of herbicides in field conditions. |
| Source | Journal of environmental quality 35 (1), pp. 312–323 |
| Journal | Journal of environmental quality |
| Editor | Published cooperatively by American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America], [Madison, Wis.,, Stati Uniti d'America |
| Year | 2006 |
| Type | Articolo in rivista |
| DOI | 10.2134/jeq2004.0025 |
| Authors | GUZZELLA L.; CAPRI E.; DI CORCIA A.; BARRA CARACCIOLO A.; GIULIANO G. |
| Text | 42115 2006 10.2134/jeq2004.0025 ISI Web of Science WOS 000235085000034 FATE OF DIURON AND LINURON IN A FIELD LYSIMETER EXPERIMENT GUZZELLA L.; CAPRI E.; DI CORCIA A.; BARRA CARACCIOLO A.; GIULIANO G. GUZZELLA L., CNR IRSA, Brugherio MB ; CAPRI E., Universita del Sacro Cuore, Piacenza; DI CORCIA A., Dipartimento di Chimica, Universita la Sapienza di Roma; BARRA CARACCIOLO A., GIULIANO G., CNR IRSA, Roma The environmental fate of herbicides can be studied at different levels in the lab with disturbed or undisturbed soil columns or in the field with suction cup lysimeters or soil enclosure lysimeters. A field lysimeter experiment with 10 soil enclosures was performed to evaluate the mass balance in different environmental compartments of the phenylurea herbicides diuron 3 3,4 diclorophenyl 1,1 dimethylurea and linuron 3 3,4 dichlorophenyl 1 methoxy 1 methylurea . After application on the agricultural soil, the herbicides were searched for in soil, pore water, and air samples. Soil and water samples were collected at different depths of the soil profile and analyzed to determine residual concentrations of both the parent compounds and of their main transformation products, to verify their persistence and their leaching capacity. Air volatilization was calculated using the theoretical profile shape method. The herbicides were detected only in the surface layer 0 10 cm of soil. In this layer, diuron was reduced to 50% of its initial concentration at the end or the experiment, while linuron was still 70% present after 245 it. The main metabolites detected were DCPMU 3 3,4 dichlorophenyl 1 methylurea and DCA 3,4 dichloroaniline . In soil pore water, diuron and linuron were detected at depths of 20 and 40 cm, although in very low concentrations. Therefore the leaching of these herbicides was quite low in this experiment. Moreover, volatilization losses were inconsequential. The calculated total mass balance showed a high persistence of linuron and diuron in the soil, a low mobility in soil pore water less than 0.5% in leachate water , and a negligible volatilization effect. The application of the Pesticide Leaching Model PELMO showed similar low mobility of the chemicals in soil and water, but overestimated their volatilization and their degradation to the metabolite DCPMU. In conclusion, the use of soil enclosure lysimeters proved to be a good experimental design for studying mobility and transport processes of herbicides in field conditions. 35 articolo JEQGuzzellaetal.pdf Articolo in rivista Published cooperatively by American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America 0047 2425 Journal of environmental quality Journal of environmental quality J. environ. qual. Journal of environmental quality. JEQ Environmental quality GIULIANO GIUSEPPE GENNARO liciamaria.guzzella GUZZELLA LICIA MARIA anna.barracaracciolo BARRA CARACCIOLO ANNA TA.P04.021.005 Tendenze evolutive della qualita dei corpi idrici superficiali e sotterranei correlazione causa effetto e caratterizzazione. |
