On the calculation of the topographic wetness index: evaluation of different methods based on field observations
International audience The topographic wetness index (TWI, ln( a /tan ? )), which combines local upslope contributing area and slope, is commonly used to quantify topographic control on hydrological processes. Methods of computing this index differ primarily in the way the upslope contributing area...
Main Authors: | , , |
---|---|
Other Authors: | , , , , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
HAL CCSD
2006
|
Subjects: | |
Online Access: | https://hal.science/hal-00304825 https://hal.science/hal-00304825/document https://hal.science/hal-00304825/file/hess-10-101-2006.pdf |
id |
ftinsu:oai:HAL:hal-00304825v1 |
---|---|
record_format |
openpolar |
spelling |
ftinsu:oai:HAL:hal-00304825v1 2023-11-12T04:23:23+01:00 On the calculation of the topographic wetness index: evaluation of different methods based on field observations Sørensen, R. Zinko, U. Seibert, J. Department of Environmental Assessment Swedish University of Agricultural Sciences (SLU) Department of Ecology and Environmental Science Umeå Umeå University Department of Physical Geography and Quaternary Geology 2006-02-15 https://hal.science/hal-00304825 https://hal.science/hal-00304825/document https://hal.science/hal-00304825/file/hess-10-101-2006.pdf en eng HAL CCSD European Geosciences Union hal-00304825 https://hal.science/hal-00304825 https://hal.science/hal-00304825/document https://hal.science/hal-00304825/file/hess-10-101-2006.pdf info:eu-repo/semantics/OpenAccess ISSN: 1812-2108 EISSN: 1812-2116 Hydrology and Earth System Sciences Discussions https://hal.science/hal-00304825 Hydrology and Earth System Sciences Discussions, 2006, 10 (1), pp.101-112 [SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces environment [SDU.OCEAN]Sciences of the Universe [physics]/Ocean Atmosphere [SDU.STU]Sciences of the Universe [physics]/Earth Sciences info:eu-repo/semantics/article Journal articles 2006 ftinsu 2023-10-25T16:26:01Z International audience The topographic wetness index (TWI, ln( a /tan ? )), which combines local upslope contributing area and slope, is commonly used to quantify topographic control on hydrological processes. Methods of computing this index differ primarily in the way the upslope contributing area is calculated. In this study we compared a number of calculation methods for TWI and evaluated them in terms of their correlation with the following measured variables: vascular plant species richness, soil pH, groundwater level, soil moisture, and a constructed wetness degree. The TWI was calculated by varying six parameters affecting the distribution of accumulated area among downslope cells and by varying the way the slope was calculated. All possible combinations of these parameters were calculated for two separate boreal forest sites in northern Sweden. We did not find a calculation method that performed best for all measured variables; rather the best methods seemed to be variable and site specific. However, we were able to identify some general characteristics of the best methods for different groups of measured variables. The results provide guiding principles for choosing the best method for estimating species richness, soil pH, groundwater level, and soil moisture by the TWI derived from digital elevation models. Article in Journal/Newspaper Northern Sweden Institut national des sciences de l'Univers: HAL-INSU |
institution |
Open Polar |
collection |
Institut national des sciences de l'Univers: HAL-INSU |
op_collection_id |
ftinsu |
language |
English |
topic |
[SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces environment [SDU.OCEAN]Sciences of the Universe [physics]/Ocean Atmosphere [SDU.STU]Sciences of the Universe [physics]/Earth Sciences |
spellingShingle |
[SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces environment [SDU.OCEAN]Sciences of the Universe [physics]/Ocean Atmosphere [SDU.STU]Sciences of the Universe [physics]/Earth Sciences Sørensen, R. Zinko, U. Seibert, J. On the calculation of the topographic wetness index: evaluation of different methods based on field observations |
topic_facet |
[SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces environment [SDU.OCEAN]Sciences of the Universe [physics]/Ocean Atmosphere [SDU.STU]Sciences of the Universe [physics]/Earth Sciences |
description |
International audience The topographic wetness index (TWI, ln( a /tan ? )), which combines local upslope contributing area and slope, is commonly used to quantify topographic control on hydrological processes. Methods of computing this index differ primarily in the way the upslope contributing area is calculated. In this study we compared a number of calculation methods for TWI and evaluated them in terms of their correlation with the following measured variables: vascular plant species richness, soil pH, groundwater level, soil moisture, and a constructed wetness degree. The TWI was calculated by varying six parameters affecting the distribution of accumulated area among downslope cells and by varying the way the slope was calculated. All possible combinations of these parameters were calculated for two separate boreal forest sites in northern Sweden. We did not find a calculation method that performed best for all measured variables; rather the best methods seemed to be variable and site specific. However, we were able to identify some general characteristics of the best methods for different groups of measured variables. The results provide guiding principles for choosing the best method for estimating species richness, soil pH, groundwater level, and soil moisture by the TWI derived from digital elevation models. |
author2 |
Department of Environmental Assessment Swedish University of Agricultural Sciences (SLU) Department of Ecology and Environmental Science Umeå Umeå University Department of Physical Geography and Quaternary Geology |
format |
Article in Journal/Newspaper |
author |
Sørensen, R. Zinko, U. Seibert, J. |
author_facet |
Sørensen, R. Zinko, U. Seibert, J. |
author_sort |
Sørensen, R. |
title |
On the calculation of the topographic wetness index: evaluation of different methods based on field observations |
title_short |
On the calculation of the topographic wetness index: evaluation of different methods based on field observations |
title_full |
On the calculation of the topographic wetness index: evaluation of different methods based on field observations |
title_fullStr |
On the calculation of the topographic wetness index: evaluation of different methods based on field observations |
title_full_unstemmed |
On the calculation of the topographic wetness index: evaluation of different methods based on field observations |
title_sort |
on the calculation of the topographic wetness index: evaluation of different methods based on field observations |
publisher |
HAL CCSD |
publishDate |
2006 |
url |
https://hal.science/hal-00304825 https://hal.science/hal-00304825/document https://hal.science/hal-00304825/file/hess-10-101-2006.pdf |
genre |
Northern Sweden |
genre_facet |
Northern Sweden |
op_source |
ISSN: 1812-2108 EISSN: 1812-2116 Hydrology and Earth System Sciences Discussions https://hal.science/hal-00304825 Hydrology and Earth System Sciences Discussions, 2006, 10 (1), pp.101-112 |
op_relation |
hal-00304825 https://hal.science/hal-00304825 https://hal.science/hal-00304825/document https://hal.science/hal-00304825/file/hess-10-101-2006.pdf |
op_rights |
info:eu-repo/semantics/OpenAccess |
_version_ |
1782338174505189376 |