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Marta Ferran - One of the best experts on this subject based on the ideXlab platform.
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risk of serious adverse events associated with biologic and nonbiologic psoriasis systemic therapy patients ineligible vs eligible for randomized controlled trials
Archives of Dermatology, 2012Co-Authors: I Garciadoval, G Carretero, J L Sanchezcarazo, F J Gomezgarcia, Montserrat Alsina, Cristina Ferrándiz, Esteban Daudén, Enrique Herreraceballos, F. Vanaclocha, Marta FerranAbstract:Objective To describe the use of systemic therapy for psoriasis (biologic and nonbiologic [classic] drugs) in patients not adequately represented in randomized controlled trials (RCTs) and the risk of serious adverse events (SAEs) in these patients. Design A registry inception cohort was used. Setting Thirteen dermatology departments in Spain participated. Patients A consecutive Sample of patients treated with biologics and a Systematic Sample of patients treated with classic systemic therapy were evaluated. A total of 1042 patients (2179 person-years) were included. Exposure Inadequate representation in trials was defined as the presence of any of the following factors: elderly age (>70 years); type of psoriasis other than chronic plaque psoriasis; history of infection caused by hepatitis B, hepatitis C, or human immunodeficiency virus; history of cancer (excluding nonmelanoma skin cancer); and chronic renal or hepatic disease. Main Outcome Measures Serious adverse events as defined by the International Conference on Harmonization were evaluated. Results In all, 29.8% of patients receiving systemic therapy for psoriasis would not have been eligible for RCTs. These individuals had an increased risk of SAEs (incidence rate ratio, 2.7; 95% CI, 1.5-4.7). Patients exposed to biologics had an adjusted increased risk of SAEs (incidence rate ratio, 2.3; 95% CI, 1.1-4.8) that was similar in patients eligible and ineligible for RCTs. Conclusions Patients ineligible for RCTs are an important proportion (30%) of those receiving systemic therapy for psoriasis. These patients have a higher risk of SAEs and should be closely monitored. Patients exposed to biologics (whether these patients are eligible for RCTs or ineligible) are susceptible to the same increase in risk of SAEs, but biologics add to a higher baseline risk in patients who are ineligible for RCTs. The risk-benefit ratio in ineligible patients receiving biologics might be different from the ratio in eligible patients.
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risk of serious adverse events associated with biologic and nonbiologic psoriasis systemic therapy patients ineligible vs eligible for randomized controlled trials
Archives of Dermatology, 2012Co-Authors: I Garciadoval, G Carretero, J L Sanchezcarazo, F J Gomezgarcia, Montserrat Alsina, Cristina Ferrándiz, Esteban Daudén, Enrique Herreraceballos, F. Vanaclocha, Marta FerranAbstract:Objective To describe the use of systemic therapy for psoriasis (biologic and nonbiologic [classic] drugs) in patients not adequately represented in randomized controlled trials (RCTs) and the risk of serious adverse events (SAEs) in these patients. Design A registry inception cohort was used. Setting Thirteen dermatology departments in Spain participated. Patients A consecutive Sample of patients treated with biologics and a Systematic Sample of patients treated with classic systemic therapy were evaluated. A total of 1042 patients (2179 person-years) were included. Exposure Inadequate representation in trials was defined as the presence of any of the following factors: elderly age (>70 years); type of psoriasis other than chronic plaque psoriasis; history of infection caused by hepatitis B, hepatitis C, or human immunodeficiency virus; history of cancer (excluding nonmelanoma skin cancer); and chronic renal or hepatic disease. Main Outcome Measures Serious adverse events as defined by the International Conference on Harmonization were evaluated. Results In all, 29.8% of patients receiving systemic therapy for psoriasis would not have been eligible for RCTs. These individuals had an increased risk of SAEs (incidence rate ratio, 2.7; 95% CI, 1.5-4.7). Patients exposed to biologics had an adjusted increased risk of SAEs (incidence rate ratio, 2.3; 95% CI, 1.1-4.8) that was similar in patients eligible and ineligible for RCTs. Conclusions Patients ineligible for RCTs are an important proportion (30%) of those receiving systemic therapy for psoriasis. These patients have a higher risk of SAEs and should be closely monitored. Patients exposed to biologics (whether these patients are eligible for RCTs or ineligible) are susceptible to the same increase in risk of SAEs, but biologics add to a higher baseline risk in patients who are ineligible for RCTs. The risk-benefit ratio in ineligible patients receiving biologics might be different from the ratio in eligible patients.
Frederic Achard - One of the best experts on this subject based on the ideXlab platform.
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estimating burned area in mato grosso brazil using an object based classification method on a Systematic Sample of medium resolution satellite images
IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing, 2015Co-Authors: Yosio Edemir Shimabukuro, Dario Simonetti, Jukka Miettinen, Rene Beuchle, Rosana Cristina Grecchi, Frederic AchardAbstract:This paper presents a new approach for estimating burned areas at a regional scale, using a Systematic Sample of medium spatial resolution satellite images. This approach is based on a pan-tropical deforestation survey developed by the Joint Research Centre. We developed and tested our approach over Mato Grosso State, located in the Brazilian Legal Amazon region, with a total area of $903\,366\;\text {km}^2$ . We analyze Landsat-5 TM imagery over 77 Sample sites ( $20\;\text {km} \times 20\;\text {km}$ in size) located at each full degree confluence of latitude and longitude. Our new approach leads to an estimate of burned area for year 2010 at $66\,368\;\text {km}^2$ , representing approximately 7.3% of the Mato Grosso area. This estimate is compared to estimates from two different approaches: 1) from a method developed by the Brazilian Institute for Space Research, applied to a wall-to-wall coverage of Landsat-5 TM imagery and 2) from a method using MODIS MCD64A1 products of the University of Maryland, resulting in $70\;232$ and $55\,157\;\text {km}^2$ of burned area, respectively (representing 7.8% or 6.1% of Mato Grosso area). Our method produces statistically valid estimates of burned areas for the Brazilian State of Mato Grosso in a more efficient manner than previous methods and enables the inclusion of small burn scars typically missed by coarse resolution satellites. This approach can be applied for regional and global assessments as well as for refining and evaluating burned area products based on coarse spatial resolution imagery like MODIS or SPOT-VEGETATION.
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Change in tropical forest cover of Southeast Asia from 1990 to 2010
Biogeosciences, 2014Co-Authors: Hans-jürgen Stibig, Rastislav Raši, Frederic Achard, SALVATORE CARBONI, Jari MiettinenAbstract:Abstract. The study assesses the extent and trends of forest cover in Southeast Asia for the periods 1990–2000 and 2000–2010 and provides an overview on the main causes of forest cover change. A Systematic Sample of 418 sites (10 km × 10 km size) located at the one-degree geographical confluence points and covered with satellite imagery of 30 m resolution is used for the assessment. Techniques of image segmentation and automated classification are combined with visual satellite image interpretation and quality control, involving forestry experts from Southeast Asian countries. The accuracy of our results is assessed through an independent consistency assessment, performed from a subSample of 1572 mapping units and resulting in an overall agreement of >85% for the general differentiation of forest cover versus non-forest cover. The total forest cover of Southeast Asia is estimated at 268 Mha in 1990, dropping to 236 Mha in 2010, with annual change rates of 1.75 Mha (∼0.67%) and 1.45 Mha (∼0.59%) for the periods 1990–2000 and 2000–2010, respectively. The vast majority of forest cover loss (∼2 / 3 for 2000–2010) occurred in insular Southeast Asia. Complementing our quantitative results by indicative information on patterns and on processes of forest change, obtained from the screening of satellite imagery and through expert consultation, respectively, confirms the conversion of forest to cash crops plantations (including oil palm) as the main cause of forest loss in Southeast Asia. Logging and the replacement of natural forests by forest plantations are two further important change processes in the region.
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continental estimates of forest cover and forest cover changes in the dry ecosystems of africa between 1990 and 2000
Journal of Biogeography, 2013Co-Authors: Catherine Bodart, Andreas Brink, Francois Donnay, Andrea Lupi, Philippe Mayaux, Frederic AchardAbstract:AIM This study provides regional estimates of forest cover in dry African ecoregions and the changes in forest cover that occurred there between 1990 and 2000, using a Systematic Sample of medium-resolution satellite imagery which was processed consistently across the continent. LOCATION The study area corresponds to the dry forests and woodlands of Africa between the humid forests and the semi-arid regions. This area covers the Sudanian and Zambezian ecoregions. METHODS A Systematic Sample of 1600 Landsat satellite imagery subsets, each 20 km × 20 km in size, were analysed for two reference years: 1990 and 2000. At each Sample site and for both years, dense tree cover, open tree cover, other wooded land and other vegetation cover were identified from the analysis of satellite imagery, which comprised multidate segmentation and automatic classification steps followed by visual control by national forestry experts. RESULTS Land cover and land-cover changes were estimated at continental and ecoregion scales and compared with existing pan-continental, regional and local studies. The overall accuracy of our land-cover maps was estimated at 87%. Between 1990 and 2000, 3.3 million hectares (Mha) of dense tree cover, 5.8 Mha of open tree cover and 8.9 Mha of other wooded land were lost, with a further 3.9 Mha degraded from dense to open tree cover. These results are substantially lower than the 34 Mha of forest loss reported in the FAO's 2010 Global Forest Resources Assessment for the same period and area. MAIN CONCLUSIONS Our method generates the first consistent and robust estimates of forest cover and change in dry Africa with known statistical precision at continental and ecoregion scales. These results reduce the uncertainty regarding vegetation cover and its dynamics in these previously poorly studied ecosystems and provide crucial information for both science and environmental policies.
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forest cover changes in tropical south and central america from 1990 to 2005 and related carbon emissions and removals
Remote Sensing, 2012Co-Authors: H Eva, Frederic Achard, Rene Beuchle, Evaristo Eduardo De Miranda, Silvia Carboni, Roman Seliger, Michael Vollmar, W A Holler, O T Oshiro, Victor Barrena ArroyoAbstract:This paper outlines the methods and results for monitoring forest change and resulting carbon emissions for the 1990–2000 and 200–2005 periods carried out over tropical Central and South America. To produce our forest change estimates we used a Systematic Sample of medium resolution satellite data processed to forest change maps covering 1230 sites of 20 km by 20 km, each located at the degree confluence. Biomass data were spatially associated to each individual Sample site so that annual carbon emissions could be estimated. For our study area we estimate that forest cover in the study area had fallen from 763 Mha (s.e. 10 Mha) in 1990 to 715 Mha (s.e. 10 Mha) in 2005. During the same period other wooded land (i.e., non-forest woody vegetation) had fallen from 191 Mha (s.e. 5.5 Mha) to 184 Mha (s.e. 5.5 Mha). This equates to an annual gross loss of 3.74 Mha∙y−1 of forests (0.50% annually) between 1990 and 2000, rising to 4.40 Mha∙y−1 in the early 2000s (0.61% annually), with Brazil accounting for 69% of the total losses. The annual carbon emissions from the combined loss of forests and other wooded land were calculated to be 482 MtC∙y−1 (s.e. 29 MtC∙y−1) for the 1990s, and 583 MtC∙y−1 (s.e. 48 MtC∙y−1) for the 2000 to 2005 period. Our maximum estimate of sinks from forest regrowth in tropical South America is 92 MtC∙y−1. These estimates of gross emissions correspond well with the national estimates reported by Brazil, however, they are less than half of those reported in a recent study based on the FAO country statistics, highlighting the need for continued research in this area.
I Garciadoval - One of the best experts on this subject based on the ideXlab platform.
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risk of serious adverse events associated with biologic and nonbiologic psoriasis systemic therapy patients ineligible vs eligible for randomized controlled trials
Archives of Dermatology, 2012Co-Authors: I Garciadoval, G Carretero, J L Sanchezcarazo, F J Gomezgarcia, Montserrat Alsina, Cristina Ferrándiz, Esteban Daudén, Enrique Herreraceballos, F. Vanaclocha, Marta FerranAbstract:Objective To describe the use of systemic therapy for psoriasis (biologic and nonbiologic [classic] drugs) in patients not adequately represented in randomized controlled trials (RCTs) and the risk of serious adverse events (SAEs) in these patients. Design A registry inception cohort was used. Setting Thirteen dermatology departments in Spain participated. Patients A consecutive Sample of patients treated with biologics and a Systematic Sample of patients treated with classic systemic therapy were evaluated. A total of 1042 patients (2179 person-years) were included. Exposure Inadequate representation in trials was defined as the presence of any of the following factors: elderly age (>70 years); type of psoriasis other than chronic plaque psoriasis; history of infection caused by hepatitis B, hepatitis C, or human immunodeficiency virus; history of cancer (excluding nonmelanoma skin cancer); and chronic renal or hepatic disease. Main Outcome Measures Serious adverse events as defined by the International Conference on Harmonization were evaluated. Results In all, 29.8% of patients receiving systemic therapy for psoriasis would not have been eligible for RCTs. These individuals had an increased risk of SAEs (incidence rate ratio, 2.7; 95% CI, 1.5-4.7). Patients exposed to biologics had an adjusted increased risk of SAEs (incidence rate ratio, 2.3; 95% CI, 1.1-4.8) that was similar in patients eligible and ineligible for RCTs. Conclusions Patients ineligible for RCTs are an important proportion (30%) of those receiving systemic therapy for psoriasis. These patients have a higher risk of SAEs and should be closely monitored. Patients exposed to biologics (whether these patients are eligible for RCTs or ineligible) are susceptible to the same increase in risk of SAEs, but biologics add to a higher baseline risk in patients who are ineligible for RCTs. The risk-benefit ratio in ineligible patients receiving biologics might be different from the ratio in eligible patients.
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risk of serious adverse events associated with biologic and nonbiologic psoriasis systemic therapy patients ineligible vs eligible for randomized controlled trials
Archives of Dermatology, 2012Co-Authors: I Garciadoval, G Carretero, J L Sanchezcarazo, F J Gomezgarcia, Montserrat Alsina, Cristina Ferrándiz, Esteban Daudén, Enrique Herreraceballos, F. Vanaclocha, Marta FerranAbstract:Objective To describe the use of systemic therapy for psoriasis (biologic and nonbiologic [classic] drugs) in patients not adequately represented in randomized controlled trials (RCTs) and the risk of serious adverse events (SAEs) in these patients. Design A registry inception cohort was used. Setting Thirteen dermatology departments in Spain participated. Patients A consecutive Sample of patients treated with biologics and a Systematic Sample of patients treated with classic systemic therapy were evaluated. A total of 1042 patients (2179 person-years) were included. Exposure Inadequate representation in trials was defined as the presence of any of the following factors: elderly age (>70 years); type of psoriasis other than chronic plaque psoriasis; history of infection caused by hepatitis B, hepatitis C, or human immunodeficiency virus; history of cancer (excluding nonmelanoma skin cancer); and chronic renal or hepatic disease. Main Outcome Measures Serious adverse events as defined by the International Conference on Harmonization were evaluated. Results In all, 29.8% of patients receiving systemic therapy for psoriasis would not have been eligible for RCTs. These individuals had an increased risk of SAEs (incidence rate ratio, 2.7; 95% CI, 1.5-4.7). Patients exposed to biologics had an adjusted increased risk of SAEs (incidence rate ratio, 2.3; 95% CI, 1.1-4.8) that was similar in patients eligible and ineligible for RCTs. Conclusions Patients ineligible for RCTs are an important proportion (30%) of those receiving systemic therapy for psoriasis. These patients have a higher risk of SAEs and should be closely monitored. Patients exposed to biologics (whether these patients are eligible for RCTs or ineligible) are susceptible to the same increase in risk of SAEs, but biologics add to a higher baseline risk in patients who are ineligible for RCTs. The risk-benefit ratio in ineligible patients receiving biologics might be different from the ratio in eligible patients.
Baudouin Desclee - One of the best experts on this subject based on the ideXlab platform.
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land cover change monitoring using landsat mss tm satellite image data over west africa between 1975 and 1990
Remote Sensing, 2014Co-Authors: Marian Vittek, Andreas Brink, Francois Donnay, Dario Simonetti, Baudouin DescleeAbstract:Monitoring land cover changes from the 1970s in West Africa is important for assessing the dynamics between land cover types and understanding the anthropogenic impact during this period. Given the lack of historical land cover maps over such a large area, Landsat data is a reliable and consistent source of information on land cover dynamics from the 1970s. This study examines land cover changes occurring between 1975 and 1990 in West Africa using a Systematic Sample of satellite imagery. The primary data sources for the land cover classification were Landsat Multispectral Scanner (MSS) for 1975 and Landsat Thematic Mapper (TM) for the 1990 period. Dedicated selection of the appropriate image data for land cover change monitoring was performed for the year 1975. Based on this selected dataset, the land cover analysis is based on a Systematic Sample of 220 suitable Landsat image extracts (out of 246) of 20 km × 20 km at each one degree latitude/longitude intersection. Object-based classification, originally dedicated for Landsat TM land cover change monitoring and adapted for MSS, was used to produce land cover change information for four different land cover classes: dense tree cover, tree cover mosaic, other wooded land and other vegetation cover. Our results reveal that in 1975 about 6% of West Africa was covered by dense tree cover complemented with 12% of tree cover mosaic. Almost half of the area was covered by other wooded land and the remaining 32% was represented by other vegetation cover. Over the 1975–1990 period, the net annual change rate of dense tree cover was estimated at −0.95%, at −0.37% for the other wooded land and very low for tree cover mosaic (−0.05%). On the other side, other vegetation cover increased annually by 0.70%, most probably due to the expansion of agricultural areas. This study demonstrates the potential of Landsat MSS and TM data for large scale land cover change assessment in West Africa and highlights the importance of consistent and Systematic data processing methods with targeted image acquisition procedures for long-term monitoring.
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Land Cover Change Monitoring Using Landsat MSS/TM Satellite Image Data over West Africa between 1975 and 1990
MDPI AG, 2014Co-Authors: Marian Vittek, Andreas Brink, Francois Donnay, Dario Simonetti, Baudouin DescleeAbstract:Monitoring land cover changes from the 1970s in West Africa is important for assessing the dynamics between land cover types and understanding the anthropogenic impact during this period. Given the lack of historical land cover maps over such a large area, Landsat data is a reliable and consistent source of information on land cover dynamics from the 1970s. This study examines land cover changes occurring between 1975 and 1990 in West Africa using a Systematic Sample of satellite imagery. The primary data sources for the land cover classification were Landsat Multispectral Scanner (MSS) for 1975 and Landsat Thematic Mapper (TM) for the 1990 period. Dedicated selection of the appropriate image data for land cover change monitoring was performed for the year 1975. Based on this selected dataset, the land cover analysis is based on a Systematic Sample of 220 suitable Landsat image extracts (out of 246) of 20 km × 20 km at each one degree latitude/longitude intersection. Object-based classification, originally dedicated for Landsat TM land cover change monitoring and adapted for MSS, was used to produce land cover change information for four different land cover classes: dense tree cover, tree cover mosaic, other wooded land and other vegetation cover. Our results reveal that in 1975 about 6% of West Africa was covered by dense tree cover complemented with 12% of tree cover mosaic. Almost half of the area was covered by other wooded land and the remaining 32% was represented by other vegetation cover. Over the 1975–1990 period, the net annual change rate of dense tree cover was estimated at −0.95%, at −0.37% for the other wooded land and very low for tree cover mosaic (−0.05%). On the other side, other vegetation cover increased annually by 0.70%, most probably due to the expansion of agricultural areas. This study demonstrates the potential of Landsat MSS and TM data for large scale land cover change assessment in West Africa and highlights the importance of consistent and Systematic data processing methods with targeted image acquisition procedures for long-term monitoring
Dario Simonetti - One of the best experts on this subject based on the ideXlab platform.
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estimating burned area in mato grosso brazil using an object based classification method on a Systematic Sample of medium resolution satellite images
IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing, 2015Co-Authors: Yosio Edemir Shimabukuro, Dario Simonetti, Jukka Miettinen, Rene Beuchle, Rosana Cristina Grecchi, Frederic AchardAbstract:This paper presents a new approach for estimating burned areas at a regional scale, using a Systematic Sample of medium spatial resolution satellite images. This approach is based on a pan-tropical deforestation survey developed by the Joint Research Centre. We developed and tested our approach over Mato Grosso State, located in the Brazilian Legal Amazon region, with a total area of $903\,366\;\text {km}^2$ . We analyze Landsat-5 TM imagery over 77 Sample sites ( $20\;\text {km} \times 20\;\text {km}$ in size) located at each full degree confluence of latitude and longitude. Our new approach leads to an estimate of burned area for year 2010 at $66\,368\;\text {km}^2$ , representing approximately 7.3% of the Mato Grosso area. This estimate is compared to estimates from two different approaches: 1) from a method developed by the Brazilian Institute for Space Research, applied to a wall-to-wall coverage of Landsat-5 TM imagery and 2) from a method using MODIS MCD64A1 products of the University of Maryland, resulting in $70\;232$ and $55\,157\;\text {km}^2$ of burned area, respectively (representing 7.8% or 6.1% of Mato Grosso area). Our method produces statistically valid estimates of burned areas for the Brazilian State of Mato Grosso in a more efficient manner than previous methods and enables the inclusion of small burn scars typically missed by coarse resolution satellites. This approach can be applied for regional and global assessments as well as for refining and evaluating burned area products based on coarse spatial resolution imagery like MODIS or SPOT-VEGETATION.
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land cover change monitoring using landsat mss tm satellite image data over west africa between 1975 and 1990
Remote Sensing, 2014Co-Authors: Marian Vittek, Andreas Brink, Francois Donnay, Dario Simonetti, Baudouin DescleeAbstract:Monitoring land cover changes from the 1970s in West Africa is important for assessing the dynamics between land cover types and understanding the anthropogenic impact during this period. Given the lack of historical land cover maps over such a large area, Landsat data is a reliable and consistent source of information on land cover dynamics from the 1970s. This study examines land cover changes occurring between 1975 and 1990 in West Africa using a Systematic Sample of satellite imagery. The primary data sources for the land cover classification were Landsat Multispectral Scanner (MSS) for 1975 and Landsat Thematic Mapper (TM) for the 1990 period. Dedicated selection of the appropriate image data for land cover change monitoring was performed for the year 1975. Based on this selected dataset, the land cover analysis is based on a Systematic Sample of 220 suitable Landsat image extracts (out of 246) of 20 km × 20 km at each one degree latitude/longitude intersection. Object-based classification, originally dedicated for Landsat TM land cover change monitoring and adapted for MSS, was used to produce land cover change information for four different land cover classes: dense tree cover, tree cover mosaic, other wooded land and other vegetation cover. Our results reveal that in 1975 about 6% of West Africa was covered by dense tree cover complemented with 12% of tree cover mosaic. Almost half of the area was covered by other wooded land and the remaining 32% was represented by other vegetation cover. Over the 1975–1990 period, the net annual change rate of dense tree cover was estimated at −0.95%, at −0.37% for the other wooded land and very low for tree cover mosaic (−0.05%). On the other side, other vegetation cover increased annually by 0.70%, most probably due to the expansion of agricultural areas. This study demonstrates the potential of Landsat MSS and TM data for large scale land cover change assessment in West Africa and highlights the importance of consistent and Systematic data processing methods with targeted image acquisition procedures for long-term monitoring.
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Land Cover Change Monitoring Using Landsat MSS/TM Satellite Image Data over West Africa between 1975 and 1990
MDPI AG, 2014Co-Authors: Marian Vittek, Andreas Brink, Francois Donnay, Dario Simonetti, Baudouin DescleeAbstract:Monitoring land cover changes from the 1970s in West Africa is important for assessing the dynamics between land cover types and understanding the anthropogenic impact during this period. Given the lack of historical land cover maps over such a large area, Landsat data is a reliable and consistent source of information on land cover dynamics from the 1970s. This study examines land cover changes occurring between 1975 and 1990 in West Africa using a Systematic Sample of satellite imagery. The primary data sources for the land cover classification were Landsat Multispectral Scanner (MSS) for 1975 and Landsat Thematic Mapper (TM) for the 1990 period. Dedicated selection of the appropriate image data for land cover change monitoring was performed for the year 1975. Based on this selected dataset, the land cover analysis is based on a Systematic Sample of 220 suitable Landsat image extracts (out of 246) of 20 km × 20 km at each one degree latitude/longitude intersection. Object-based classification, originally dedicated for Landsat TM land cover change monitoring and adapted for MSS, was used to produce land cover change information for four different land cover classes: dense tree cover, tree cover mosaic, other wooded land and other vegetation cover. Our results reveal that in 1975 about 6% of West Africa was covered by dense tree cover complemented with 12% of tree cover mosaic. Almost half of the area was covered by other wooded land and the remaining 32% was represented by other vegetation cover. Over the 1975–1990 period, the net annual change rate of dense tree cover was estimated at −0.95%, at −0.37% for the other wooded land and very low for tree cover mosaic (−0.05%). On the other side, other vegetation cover increased annually by 0.70%, most probably due to the expansion of agricultural areas. This study demonstrates the potential of Landsat MSS and TM data for large scale land cover change assessment in West Africa and highlights the importance of consistent and Systematic data processing methods with targeted image acquisition procedures for long-term monitoring
