Manifestation of Land Use/Land Cover Change Analysis and Its Impacts on Soil Properties in Gadarif Region, Sudan Faculty of Forest, Geo and Hydro Sciences, Department of Geosciences, Institute for Cartography Khalid Guma Biro, PhD student Supervisor: Prof. Manfred Buchroithner Fortaleza, Ceará, Brazil, 01 – 12 November 2010
2 Main topics Use of multi-temporal satellite data for land use/land cover change analysis Impacts of land use/land cover changes on soil properties Soil compaction and infiltration rate characteristics under three different land use types in dryland vertisols Land use analyses in drylands: an object-oriented classification approach using TerraSAR-X data Synthesis: Discussion of interconnections and implications for soil conservation, soil management and sustainable land use Fortaleza,
3 Study area African Sahel (Source: NASA Earth Observatory, 2007) Gadarif Region East Sudan Study site: Area: 40 x 30 km² Average altitude: 600 m
4 Analysis of LULC change using optical data Fortaleza, Unclassified (raw) images from Landsat and ASTER data Acquisition date SensorGeometric resolution Spectral resolution MSS57 m4 bands TM30 m6 bands ETM+30 m7 bands ASTER15 m3 bands
Fortaleza, Maximum likelihood classification showing LULC through the period 1979 – 2009
Fortaleza, Areas of LULC classes in the study area
Fortaleza, Change detection (%) for the period (Diagonal represents unchanged fraction of each class) Change from Cultivated land WoodlandFallow landBarelandSettlementWater Cultivated land Woodland Fallow land Bareland Settlement
Fortaleza, LULC changes in the period 1979 – 2009
Fortaleza, LULC changes in the period 1979 – 2009
10 Land use analysis using TerraSAR-X data Study area Descending Ascending Fortaleza, Acquisition date Sensor mode Geometric resolution Incidence Angle Strip map4 m33.32º Strip map4 m32.25º Data acquisition
Image filtering 11 Fortaleza, σ ºdB = βº dB + 10 * Log10 (sin (θloc) (1) (Infoterra, 2008) βºdB = 10 * Log10 (Ks * DN²) (2) Where: σ ºdB = backscattering coefficient in dB θloc = local incidence angle from GIM βºdB = radar brightness in dB Ks = TerraSAR-X calibration factor DN = digital number of TerraSAR-X EEC input image pixel. Normalize image backscattering coefficient
12 Gamma speckle filtering (7x7) HVHHHH/HV Raw Filtered Fortaleza,
13 Image segmentation Fortaleza, Segmentation levelScale parameterColour/Shape ٭ Image weight Level /0.11 : 1 Level /0.21 : 1 Level /0.11 : 1 Level /0.21 : 1 Segmentation parameters (using multiresolution algorithm of eCognition) ٭ Smoothness/compactness were constant at 0.5/0.5 HV HH HH/HV
14 Feature space optimization Classification was based on nearest neighbour classifier using feature space optimisation GLCM = Gray level co-occurrence matrix StdDev = Standard deviation Invert expression also used for select class feature Fortaleza,
15 TerraSAR-X land use/cover map
16 Fortaleza, TerraSAR-X land use/cover map
17 Fortaleza, TerraSAR-X land use/cover map
18 Summary of classification accuracies Fortaleza, Class Accuracy (%) Conditional kappaArea (%) Producer’sUser’s Cultivated land Harvested land Fallow land Woodland Bareland Rock Settlement Settlement Water Overall accuracy (%)94 Kappa coefficient0.93
19 Impacts of land use change on soil properties Fortaleza, Soil physical properties
20 Fortaleza, Soil chemical properties
21 Fortaleza, Soil penetration resistance
22 Fortaleza, Soil infiltration (Kostiakov model)
23 Fortaleza, Maps of soil penetration resistance
24 Fortaleza, Maps of soil organic carbon
25 Fortaleza, Maps of soil moisture content
26 Use of multi-temporal satellite data for land use/land cover change analyses and its impacts on soil properties in the northern part of Gadarif region, Sudan; 30th EARSeL Symposium Paris, France. (submitted to Land Degradation and Development, Revised). Land use analyses in the African Sahel: an object-oriented classification approach using TerraSAR-X data; 38th COSPAR Scientific Assembly, July 2010,Bremen, Germany. (Submitted to Advances in Space Research, Revised). The effects of different land use types on soil compaction and infiltration rate in the drylands vertisol of Gadarif region, Sudan; Tropentag 2010, ETH Zurich September , (Under work). Fortaleza,
26 Thank You! Fortaleza,