Identification of drainage basin borders at local spatial scale

Abstract

The basin concept to nature management is used in various studies on ecological monitoring of terrestrial ecosystems. The objective of this study is to identify the borders of drainage basins on the territory of Pechora-Ilych Nature Reserve and its surroundings – Kuryinsky and Yakshinsky local forestries. Digital elevation models (DEMs) ASTER GDEM Version 2, GMTED2010, and open access data of the drainage network at a scale of 1 : 1,000,000 were the inputs for the identification of drainage basin borders of the area of interest. These data were processed and analyzed with two geographic information systems, i. e. SAGA GIS and ArcGIS Desktop software. The present study involved pre-processing of the DEM data and identification of the drainage basin borders of the area of interest. Pre-processing of DEMs data included rasters’ cell size unification, filling sinks, and determining flow direction. Identification of drainage basin borders was performed in two ways using the Basin and Watershed tools of the Spatial Analyst module of the ArcGIS Desktop geographic information system. Analysis of the findings showed that the Basin tool was only able to identify basin borders of large rivers such as Pechora and Ilych. The Watershed tool using raster data on pour points is suitable to form basin borders of both large and small rivers.