|Heighton Davies, Lynne|
|Hetzer, Paul - UNIV OF MD, CBL|
|Baker, Joel - UNIV OF MD, CBL|
Submitted to: SETAC Conference
Publication Type: Abstract Only
Publication Acceptance Date: November 13, 2000
Publication Date: N/A
Technical Abstract: Runoff from vegetable production on the Chesapeake Bay Delmarva peninsula has been implicated in the failure of shellfish farms. Current vegetable production systems utilize polyethylene mulch and require multiple applications of pesticides and fertilizers. During rain events, runoff from vegetable production is enhanced because 50 to 75 percent of the field is covered with an impervious surface. Thus, the potential harmful effects on organisms in nearby streams and rivers from off-site losses of agrochemicals is substantially increased. An economically-viable sustainable management strategy for fresh-market tomato production that does not utilize polyethylene has been developed. However, resistance of growers to move away from polyethylene may slow its implementation. The objective of our research was to quantify and compare the environmental impact of conventional polyethylene mulch and hairy vetch mulch systems. To odate, our research using side-by-side instrumented field plots has shown losses of 2 to 10 times more water, and twice as much sediment occurs from plots utilizing polyethylene mulch and toxicity tests with aquatic organisms have shown greater adverse effects associated with this runoff. Our quantitative results showing reduced off-site movement of soil and agrochemicals in the hairy vetch system provide additional support for the implementation of this management strategy. Benefits to the grower include reduced soil erosion and greater concentrations of agrochemicals remaining in the applied locations where they will provide the most effective pest control. The reduced off-site movement of agrochemicals will also benefit the environment by reducing the load of harmful substances to surrounding sensitive ecosystems.