140 likes | 302 Views
Urban Reforestation as a stormwater management tool. GEOG591 Final Project By: Sophie Wilderotter , Tyler Tran, Casey Stern, Sarah Rhodes and Kaitlin Finan. introduction. Negative Impacts of Urbanization and Impervious C over:
E N D
Urban Reforestation as a stormwater management tool GEOG591 Final Project By: Sophie Wilderotter, Tyler Tran, Casey Stern, Sarah Rhodes and Kaitlin Finan
introduction • Negative Impacts of Urbanization and Impervious Cover: • Physical impacts: Increased velocity /volume of runoff, Flooding, Erosion of Stream Banks, Decline in Infiltration and Groundwater Recharge, Degradation of Riparian Zones • Ecological Impacts: Contamination of water bodies by non-point source pollution can cause stress for aquatic organisms such as: hypoxia by nutrients (N &P), pathogen contamination of shellfish beds, physiological effects by toxic chemicals • (Arnold and Gibbons, 1996)
A storm-water Management tool: Reforestation • Increased evapotranspiration • Reduced runoff • Potential tool for Carbon sequestration
Study objectives • Quantify and characterize the tree cover, including the life form, extent of trees and LAI, in Chapel Hill and Carrboro, NC • Determine suitable regions for reforestation in Chapel Hill and Carrboro alongside roadways and sidewalks and areas of low LAI • Estimate the water balance change that would result from increasing tree cover in this region.
Study site • Municipalities of Chapel Hill and Carrboro combined • 77.2 square kilometers • Created a shape file of the outline of our study area
Methods: LAI AND Tree Extent • LAI from EVI and Dr. Song, Forests from NLCD • Raster Calculator • BL_LAI = (NLCD==41)*LAI • CN_LAI = (NLCD==42)*LAI • MX_LAI = (NLCD==43)*LAI
Continued • Weighted Average LAI by tree type in Excel • Reclassification to find extent of Trees
Tree Cover Extent by LAI • Average LAI Results: • Conifer: 6.06 • Deciduous: 8.32 • Mixed: 6.64
Results: Tree cover extent by tree type • Conifer= • 6.3 km2, 8.2% • Deciduous= • 11.9 km2, 15.4% • Mixed= • 1.3 km2, 1.7%
Impervious, Grass and Barren in Chapel Hill/Carrboro • Potential for Tree Cover Expansion (Tyler and Sarah) • Grass/barren land, parking lots, alongside streams, sidewalks not surrounded by impervious • Using CH/Carrboro mask of South Orange Classification, we determined areas of barren land, impervious surface, and grass. Calculate proportion of these areas that would be appropriate for reforestation
Potential for Reforestation alongside roads/sidewalks • Buffer Information: We created a 2m buffer surrounding impervious surfaces in CH/Carrboro, here is the area of the buffer covered by grass and barren: • Grass: 2,120,780m2 • Barren: 28,914m2 • Area of impervious covered if broadleaved were to be planted in suitable areas around roads/sidewalks= • (4.09m)*(1,074,847m)= 4,396,124.23m2 interference area • 2. Area of impervious covered if loblolly pines were to be planted in suitable areas around roads/sidewalks= • (3.175)*( 1,074,847m)=3,412,639.23m2 interference area
References • http://26.media.tumblr.com/tumblr_l7lcjyuJiX1qdstgoo1_500.jpg: Algal blooms • http://media.treehugger.com/assets/images/2011/10/peru-national-reforestation-campaign.jpg: planting woman