human activity

1. agriculture urbanization industry channel alteration upstream impoundment riparian devegetation WWTP effluent other point sources industrial effluent stormwater drainage downstream impoundment groundwater withdrawals surface water withdrawals watershed devegetation tile drains forestry & silviculture mining & resource extraction human activity ↓ groundwater inputs ↓ surface water inputs ↑ overland transport efficiency ↑ discharge regulation ↑ discharge into surface waters ↓ infiltration Δ channel morphology ↓ water uptake ↓ sinuosity ↑ armoring ↑ surface runoff ↓ permeability ↑ incision additional step in causal pathway source Δ physical habitat other stressors ↑ stranding Δ discharge patterns Δ structural habitat mode of action ↑ water velocity ↓ water depth ↓magnitude, ↑ frequency of low discharges ↑ magnitude, ↑ frequency of high discharges ↓magnitude, ↓ frequency of high discharges Δ discharge pattern timing or sequencing ↑ magnitude, ↓ frequency of low discharges ↑ daily discharge variability ↓ seasonal discharge variability Δ discharge duration response ↑ water column habitat ↑ scouring & displacement ↑ channel drying ↓ scouring & displacement Δ life cycle cues ↓ floodplain inundation ↓ wetted channel area ↓ scouring & displacement ↑ scouring & displacement ↓ slow water habitat ↓ water column habitat Detailed conceptual diagram for FLOW ALTERATION Developed 7/2007 by Kate Schofield & Rick Ziegler; modified 7/2010 ↓ macrophytes ↓ EPT taxa ↑ bryophytes ↑ macrophytes ↑ lentic taxa LEGEND ↑ water depth ↓ water velocity proximate stressor interacting stressor ↑ non-native taxa ↓ floodplain-dependent taxa or life stages ↓ drought-tolerant taxa ↑ drought-tolerant taxa ↓ water column taxa ↑ water column taxa ↓ benthic taxa or life stages ↓ benthic taxa or life stages ↓ fish richness or diversity ↓ invertebrate richness or diversity ↑ other impairments ↓ plant richness or diversity