Detection of potential arable land with remote sensing and GIS : a case study for Kjósarhreppur

Arable land is a valuable natural resource. In Iceland the total size of potential arable land has not been determined but preliminary estimates vary from 420 ha to 15000 ha. These have been based on different definitions of potential arable land and assumptions for minimum continuous land area. In...

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Bibliographic Details
Main Author: Gudmundsdottir, Brynja
Format: Other/Unknown Material
Language:English
Published: Lunds universitet/Institutionen för naturgeografi och ekosystemvetenskap 2014
Subjects:
GIS
Online Access:http://lup.lub.lu.se/student-papers/record/4522912
Description
Summary:Arable land is a valuable natural resource. In Iceland the total size of potential arable land has not been determined but preliminary estimates vary from 420 ha to 15000 ha. These have been based on different definitions of potential arable land and assumptions for minimum continuous land area. In 2010 the Farmers Association of Iceland concluded that there was a need for a standard for evaluating potential arable land, which could be used in planning and strategic planning for land use. In the Planning Act (No 123/2010) that came into force in 2011 and the Planning Regulation (from 27 October 2010) municipalities are required to define both arable and potential arable land. A definition of arable land was agreed upon and subsequently proposed to the Agricultural Assembly in February 2011. Arable land is well defined but it is not as straightforward to define potential arable land. The current definition of arable land includes areas below 200 m a.s.l, with slope less than 10º, not in protected areas nor in wetlands larger than 3ha and with minimum continuous size of 3 ha. The aim of this study was to use this definition to develop a digital method to define and locate potential arable land that would be possible to use in strategy planning and planning work for land use. The municipality of Kjósarhreppur was used as a case study. The following sources were used for the analysis: satellite image data, aerial photographs, the Icelandic Farmland Database, Icelandic Geographical Land Use Database, contour lines, elevation points, and roads, lakes and rivers from the municipality of Kjósarhreppur. Digital elevation model (DEM) was developed to delimit land below 200 m a.s.l. and slope less than 10°. Image classification was used to find arable and potential arable land, both with supervised and unsupervised classification. Supervised classification gave better results than unsupervised. Subsequently, attempts were made to identify potential arable land using vegetation indices. The normalized difference vegetation ...