Off-site Transport Of Pesticides Research Articles

Evaluation of individual and combined management practices to reduce the off-site transport of pesticides from golf course turf.

The detection of pesticides, associated with turfgrass management, in storm runoff and surface waters of urban watersheds has raised concerns regarding their source, potential environmental effects and a need for strategies to reduce their inputs. In previous research we discovered that hollow tine core cultivation (HTCC) was more effective than other management practices for reducing the off-site transport of pesticides with runoff from creeping bentgrass turf managed as a golf course fairway. This was primarily the result of enhanced infiltration and reduced runoff volumes associated with turf managed with hollow tines. In this study we evaluated the addition of verticutting (VC) to HTCC (HTCC+VC) in an attempt to further enhance infiltration and mitigate the off-site transport of pesticides with runoff from managed turf. Overall, greater or equal quantities of pesticides were transported with runoff from plots managed with HTCC+VC compared to HTCC or VC alone. For the pesticides evaluated HTCC<VC<HTCC+VC for the off-site transport of the high mobility pesticides while HTCC=VC=HTCC+VC for the low mobility pesticides. It is likely the addition of VC following HTCC further increased compaction and reduced availability of recently exposed soil sorptive sites produced from the HTCC. Results of this research provides guidance to golf course managers on selection of management practices that assure quality turf while minimizing off-site transport of pesticides, improving pesticide efficacy and the environmental stewardship of managed biological systems.

English

In this study the concentrations of the atrazine, desethylatrazine (DEA), desisopropylatrazine (DIA), azoxistrobin, carbendazim, carbofuran, chlorpyrifos, diuron, endosulfan alpha and beta endosulfan sulfate, malathion, metolachlor, methomyl, monocrotofos, permethrin, profenofos, teflubenzuron, thiacloprid, tiametoxan and triflumuron were assessed in runoff water from cotton plantations under different management systems in Central-Western Brazil. The runoff water was collected from plots delimitated by steel plates, where cotton was sown under no-tillage (direct seeding) and conventional soil management systems in one farm; and no-tillage soil management systems with and without a vegetated filter strip (buffer filter) planted with Bracchiaria grass in a second farm. In general terms, there was a 51% reduction in the total mass of off-site transport of pesticides in the no-tillage system compared to the conventional tillage. In addition, when comparing the no-tillage system with conventional tillage, the pesticides: metolachlor and alfa endosulfan as well as endosulfan sulfate, its metabolite, showed the lowest reduction in relation to the other pesticides transported by runoff. Thus, these pesticides showed broad risk of contamination of surface waters. Besides, the buffer filter reduced the off-site transport of pesticides by runoff in 92%, confirming the efficiency of a Bracchiaria filter strip in the retention of pesticides carried by runoff. Key words: Runoff water, buffer filter, direct seeding, conventional plantation system.

Off-site transport of pesticides in dissolved and particulate forms from two land uses in the Mt. Lofty Ranges, South Australia

Abstract The form in which pesticides are transported off-site can have implications for their bioavailability, ecotoxicological impact and the effectiveness of any management strategies implemented to minimise their movement. We have investigated the form in which nine pesticides (carbaryl, fenarimol, azinphos methyl, penconazole, pirimicarb, chlorpyrifos, propiconazole, procymidone and bupirimate) were transported in surface water from an apple and cherry orchard in the Mt. Lofty Ranges, South Australia, over three years. The majority of pesticides monitored were found to move off-site in the dissolved ( 1.2 μm) material. Chlorpyrifos was detected in surface drainage water for several months and the predominant phase in which it moved varied between events in a year and during an event. The effectiveness of pesticide physicochemical properties as surrogates for predicting mode of transport of pesticides, in this region was determined by regression of average proportion (%) of each pesticide in the dissolved phase for each event against the relevant physicochemical parameters. There was no relationship between average proportion in the dissolved phase (

Pesticide transport with runoff from creeping bentgrass turf: Relationship of pesticide properties to mass transport

The off-site transport of pesticides with runoff is both an agronomic and environmental concern, resulting from reduced control of target pests in the area of application and contamination of surrounding ecosystems. Experiments were designed to measure the quantity of pesticides in runoff from creeping bentgrass (Agrostis palustris) turf managed as golf course fairway to gain a better understanding of factors that influence chemical availability and mass transport. Less than 1 to 23% of applied chloropyrifos, flutolanil, mecoprop-p (MCPP), dimethylamine salt of 2,4-dichlorophenoxyacetic acid (2,4-D), or dicamba was measured in edge-of-plot runoff when commercially available pesticide formulations were applied at label rates 23 +/- 9 h prior to simulated precipitation (62 +/- 13 mm). Time differential between hollow tine core cultivation and runoff did not significantly influence runoff volumes or the percentage of applied chemicals transported in the runoff. With the exception of chlorpyrifos, all chemicals of interest were detected in the initial runoff samples and throughout the runoff events. Chemographs of the five pesticides followed trends in agreement with mobility classifications associated with their soil organic carbon partition coefficient (K(OC).) Data collected from the present study provides information on the transport of chemicals with runoff from turf, which can be used in model simulations to predict nonpoint source pollution potentials and estimate ecological risks.

Evaluation of core cultivation practices to reduce ecological risk of pesticides in runoff from Agrostis palustris

Pesticides associated with the turfgrass industry have been detected in storm runoff and surface waters of urban watersheds, invoking concern of their potential environmental effects and a desire to reduce their transport to nontarget locations. Quantities of chlorpyrifos, dicamba, dimethylamine salt of 2,4-dichlorophenoxyacetic acid (2,4-D), flutolanil, and mecoprop-p (MCPP) transported in runoff from bentgrass (Agrostis palustris) fairway turf managed with solid tine (ST) or hollow tine (HT) core cultivation were compared to determine which cultivation practice is more efficient at mitigating environmental risk. Plots receiving HT core cultivation showed a 10 and 55% reduction in runoff volume and a 15 to 57% reduction in pesticide transport with runoff at 63 d and 2 d following core cultivation. Estimated environmental concentrations of the pesticides in a surface water receiving runoff from turf managed with ST core cultivation exceeded the median lethal concentration (LC50) or median effective concentration (EC50) of nine aquatic organisms evaluated. Replacing ST core cultivation with HT core cultivation reduced surface water concentrations of the pesticides to levels below the LC50 and EC50 for most these aquatic organisms, lessening risk associated with pesticides in runoff from the fairway turf. Results of the present research provide quantitative information that will allow for informed decisions on cultural practices that can maximize pesticide retention at the site of application, improving pest control in turf while minimizing environmental contamination and adverse effects associated with the off-site transport of pesticides.

Solute Transport in Eroded and Rehabilitated Prairie Landforms. 2. Reactive Solute

The impact of varying soil, landscape, and climate conditions on the off-site transport of pesticides must be determined to develop improved pesticide management practices. This study quantified the rate of S-metolachlor dissipation after fall and spring application in eroded and rehabilitated landforms in which topsoil was moved from the lower slope to the upper slope. Fall-applied metolachlor provided no control of annual grasses because approximately 80% was removed from the root zone during the winter and early spring, presumably by leaching and runoff. S-Metolachlor dissipated in the spring with a DT(50) of 24-29 days. These results suggest that fall-applied metolachlor may not provide economic weed control and presents an increased risk of water contamination. Although landscape position and bulk soil movement within the landform had a large impact on soil properties, no significant differences in metolachlor dissipation between different landscape positions and between eroded and rehabilitated landforms were observed.

Pesticides report 35. Offsite transport of pesticides in water: Mathematical models of pesticide leaching and runoff (Technical Report)

Abstract