agriculture historical sources applied pesticides other nonpoint sources

agriculture historical sources applied pesticides other nonpoint sources mining wastes applied fertilizers urbanization septic systems landfills industry mining & resource extraction power plant releases applied road sand, salt & deicers heating emissions other combustion by-products ↑ toxics in subsurface watershed & riparian devegetation vehicle emissions detention basins industrial wastes industrial effluent WWTP effluent ↑ toxics in discharged waters ↑ toxics in surface runoff ↓ permeability precipitation ↑ surface runoff ↑ delivery of toxics to stream ↑ channel incision ↑ erosion altered flow ↓ dilution ↑ toxic chemicals ↑ temperature ↑ ionic strength ↑ bioavailability, uptake or toxicity ↑ sediment ↓ dissolved oxygen ↑ episodic exposures dissolved organic carbon ∆ behavior ↑ sustained exposures ↑ susceptibility to other stressors ↓ growth ↓ condition LEGEND human activity ↓ immigration source ↑ drift ∆ other stressors behaviors ↑ parasitism & disease ↑ DELTs ↓ other condition measures additional step in causal pathway proximate stressor ↑ mortality ↓ reproductive success modifying factor interacting stressor mode of action ∆ population & Detailed conceptual diagram for TOXIC CHEMICALS ∆ ecosystem processes community structure response ↓ sensitive taxa ↓ sensitive life stages ↑ tolerant life stages Developed 7/2007 by Kate Schofield, Suzanne Marcy & Glenn Suter; modified 6/2010 ∆ population age structure ↑ tolerant taxa ∆ other characteristics other point sources stormwater drainage ↑ toxics in wet or dry deposition ↑ toxics in soil channel alteration industrial emissions