Assessment of Forest Above-Ground Biomass Estimation from PolInSAR in the Presence of Temporal Decorrelation
In forestry studies, remote sensing has been widely used to monitor deforestation and estimate biomass, and it has contributed to forest carbon stock management. A major problem when estimating biomass from optical and SAR remote sensing images is the saturation effect. As a solution, PolInSAR offer...
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| Format: | Article |
| Language: | English |
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MDPI AG
2018-05-01
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| Series: | Remote Sensing |
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| Online Access: | http://www.mdpi.com/2072-4292/10/6/815 |
| _version_ | 1818959770073169920 |
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| author | Nafiseh Ghasemi Valentyn Tolpekin Alfred Stein |
| author_facet | Nafiseh Ghasemi Valentyn Tolpekin Alfred Stein |
| author_sort | Nafiseh Ghasemi |
| collection | DOAJ |
| description | In forestry studies, remote sensing has been widely used to monitor deforestation and estimate biomass, and it has contributed to forest carbon stock management. A major problem when estimating biomass from optical and SAR remote sensing images is the saturation effect. As a solution, PolInSAR offers a high coverage height map that can be transformed into a biomass map. Temporal decorrelation may affect the accuracy of PolInSAR and may also have an effect on the accuracy of the biomass estimates. In this study, we compared three different height estimation models: the Random-Volume-over-Ground (RVoG), Random-Motion-over-Ground (RMoG), and Random-Motion-over-Ground-Legendre (RMoG L ) models. The RVoG model does not take into account the temporal decorrelation, while the other two compensate for temporal decorrelation but differ in structure function. The comparison was done on 214 field plots of the 10 m radius of the BioSAR2010 campaign. Different models relating PolInSAR height and biomass were developed by using polynomial, exponential, power series, and piece-wise linear regression. Different strategies for training and test subset selection were followed to obtain the best possible regression models. The study showed that the RMoG L model provided the most accurate biomass predictions. The relation between RMoG L height and biomass is well expressed by the exponential model with an average RMSE equal to 48 ton ha − 1 and R 2 value equal to 0.62. The relative errors for estimated biomass were equal to 46% for the RVoG model, to 37% for the RMoG, and to 30% for the RMoG L model. We concluded that taking the temporal decorrelation into account for estimating tree height has a significant effect on providing accurate biomass estimates. |
| first_indexed | 2024-12-20T11:46:55Z |
| format | Article |
| id | doaj.art-d39bc99175ca4e72878223f78ee80926 |
| institution | Directory Open Access Journal |
| issn | 2072-4292 |
| language | English |
| last_indexed | 2024-12-20T11:46:55Z |
| publishDate | 2018-05-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Remote Sensing |
| spelling | doaj.art-d39bc99175ca4e72878223f78ee809262022-12-21T19:41:51ZengMDPI AGRemote Sensing2072-42922018-05-0110681510.3390/rs10060815rs10060815Assessment of Forest Above-Ground Biomass Estimation from PolInSAR in the Presence of Temporal DecorrelationNafiseh Ghasemi0Valentyn Tolpekin1Alfred Stein2Faculty of Geo-Information Science and Earth Observation, University of Twente, 7500 AE Enschede, The NetherlandsFaculty of Geo-Information Science and Earth Observation, University of Twente, 7500 AE Enschede, The NetherlandsFaculty of Geo-Information Science and Earth Observation, University of Twente, 7500 AE Enschede, The NetherlandsIn forestry studies, remote sensing has been widely used to monitor deforestation and estimate biomass, and it has contributed to forest carbon stock management. A major problem when estimating biomass from optical and SAR remote sensing images is the saturation effect. As a solution, PolInSAR offers a high coverage height map that can be transformed into a biomass map. Temporal decorrelation may affect the accuracy of PolInSAR and may also have an effect on the accuracy of the biomass estimates. In this study, we compared three different height estimation models: the Random-Volume-over-Ground (RVoG), Random-Motion-over-Ground (RMoG), and Random-Motion-over-Ground-Legendre (RMoG L ) models. The RVoG model does not take into account the temporal decorrelation, while the other two compensate for temporal decorrelation but differ in structure function. The comparison was done on 214 field plots of the 10 m radius of the BioSAR2010 campaign. Different models relating PolInSAR height and biomass were developed by using polynomial, exponential, power series, and piece-wise linear regression. Different strategies for training and test subset selection were followed to obtain the best possible regression models. The study showed that the RMoG L model provided the most accurate biomass predictions. The relation between RMoG L height and biomass is well expressed by the exponential model with an average RMSE equal to 48 ton ha − 1 and R 2 value equal to 0.62. The relative errors for estimated biomass were equal to 46% for the RVoG model, to 37% for the RMoG, and to 30% for the RMoG L model. We concluded that taking the temporal decorrelation into account for estimating tree height has a significant effect on providing accurate biomass estimates.http://www.mdpi.com/2072-4292/10/6/815biomasstemporal decorrelationPolInSAR heightaccuracyRVoG modelRMoG modelRMoGL model |
| spellingShingle | Nafiseh Ghasemi Valentyn Tolpekin Alfred Stein Assessment of Forest Above-Ground Biomass Estimation from PolInSAR in the Presence of Temporal Decorrelation Remote Sensing biomass temporal decorrelation PolInSAR height accuracy RVoG model RMoG model RMoGL model |
| title | Assessment of Forest Above-Ground Biomass Estimation from PolInSAR in the Presence of Temporal Decorrelation |
| title_full | Assessment of Forest Above-Ground Biomass Estimation from PolInSAR in the Presence of Temporal Decorrelation |
| title_fullStr | Assessment of Forest Above-Ground Biomass Estimation from PolInSAR in the Presence of Temporal Decorrelation |
| title_full_unstemmed | Assessment of Forest Above-Ground Biomass Estimation from PolInSAR in the Presence of Temporal Decorrelation |
| title_short | Assessment of Forest Above-Ground Biomass Estimation from PolInSAR in the Presence of Temporal Decorrelation |
| title_sort | assessment of forest above ground biomass estimation from polinsar in the presence of temporal decorrelation |
| topic | biomass temporal decorrelation PolInSAR height accuracy RVoG model RMoG model RMoGL model |
| url | http://www.mdpi.com/2072-4292/10/6/815 |
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