Detection of potential arable land with remote sensing and GIS : a case study for Kjósarhreppur
(2014) In LUMA-GIS Thesis GISM01 20122Dept of Physical Geography and Ecosystem Science
- Abstract
- 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... (More) - 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 index was selected because it is the most commonly used index. Here ancillary data, elevation, slope, water bodies and roads were used to extract data before the classification. This method was found to be easier to use and gave even better results than the image classification method. For all methods the protected areas were found and marked as such.
According to the current analysis, assuming a minimum continuous size of 3 ha, potential arable land in Kjósarhreppur municipality is 2,483 ha including 220 ha of wetlands. If the requirement of the continuous size is reduced to 2 ha or 1 ha the potential arable land would increase to 2,530 ha and 2,575 ha respectively. (Less) - Popular Abstract
- 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... (More) - 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.
A digital elevation model was developed from the elevation points and the contour lines to delimit land below 200 m a.s.l. and with slope less than 10º. Image analysis was carried out using the satellite image data and known areas from other datasets and the aerial photographs. In addition special analyses were done to find wetlands. The classification from the image analysis was verified on-site and corrected if necessary. In the field work soil depth and stoniness were closely checked but to estimate this closer look at different geo-environmental factors and research is needed. Finally, protected areas around lakes, rivers and roads were subtracted from the total area.
According to the current analysis, assuming a minimum continuous size of 3 ha, potential arable land in Kjósarhreppur municipality is 2,483 ha including 220 ha of wetlands. If the requirement of the continuous size is reduced to 2 ha or 1 ha the potential arable land would increase to 2,530 ha and 2,575 ha respectively. (Less)
Please use this url to cite or link to this publication:
http://lup.lub.lu.se/student-papers/record/4522912
- author
- Gudmundsdottir, Brynja LU
- supervisor
- organization
- course
- GISM01 20122
- year
- 2014
- type
- H2 - Master's Degree (Two Years)
- subject
- keywords
- Physical Geography and Ecosystem analysis, GIS, remote sensing, potential arable land, general plan, Kjósarhreppur
- publication/series
- LUMA-GIS Thesis
- report number
- 29
- funder
- The Icelandic National Planning Agency
- language
- English
- additional info
- External supervisor Dr Áslaug Helgadóttir, Agricultural University of Iceland
- id
- 4522912
- date added to LUP
- 2014-07-01 10:01:42
- date last changed
- 2014-07-09 11:32:48
@misc{4522912,
abstract = {{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 index was selected because it is the most commonly used index. Here ancillary data, elevation, slope, water bodies and roads were used to extract data before the classification. This method was found to be easier to use and gave even better results than the image classification method. For all methods the protected areas were found and marked as such.
According to the current analysis, assuming a minimum continuous size of 3 ha, potential arable land in Kjósarhreppur municipality is 2,483 ha including 220 ha of wetlands. If the requirement of the continuous size is reduced to 2 ha or 1 ha the potential arable land would increase to 2,530 ha and 2,575 ha respectively.}},
author = {{Gudmundsdottir, Brynja}},
language = {{eng}},
note = {{Student Paper}},
series = {{LUMA-GIS Thesis}},
title = {{Detection of potential arable land with remote sensing and GIS : a case study for Kjósarhreppur}},
year = {{2014}},
}