Riparian Buffer Removal and Associated Land Use in the Sackville River Watershed, Nova Scotia, Canada

Abstract

“To what extent has riparian area been removed in the Sackville River watershed and what land uses are associated with this riparian area removal?” I investigate this question by assessing the extent of riparian area removal in the Sackville River watershed north of Halifax and characterizing each riparian impact zone with the neighbouring land use. Stream, lake and road data and air photographs are used in Geographic Information Systems (GIS) to document the degree of riparian area removal and the land uses associated with the riparian area (agriculture, industry, forestry, residential etc). I consider the riparian area to be a 20m zone extending from the water body’s edge. Over 143km of streams are assessed and all streams are broken down into reaches of discrete lengths based on riparian impact and land use category. Four qualitative indicators of riparian removal are used: Severe, Moderate, Low and Intact. The length of every reach as well as the degree of impact and associated land use are calculated using the summary statistics function in GIS. I found that one third of the total riparian area length is missing up to 50% of its vegetation and that residential, transportation and energy infrastructure were the leading drivers of this riparian buffer removal. I present a map of impacted riparian “hot spots” that will highlight the areas in which riparian area removal is the most severe as well as summaries of the land uses most associated with the greatest degree of riparian vegetation removal. Identification of the land use drivers of riparian area removal in this watershed will help the design of effective regulations for future development in riparian buffer zones.