G.O. Enaruvbe & G.U. YesufRegional Centre for Training in Aerospace Surveys  (RECTAS) Obafemi Awolowo University, Ile-Ife,...
Introduction Flood disasters are among the most destructive natural disaster in history. Flooding has become more prevalen...
Introduction Contd Coastal farming communities are the most adversely affected as their farms and fishing implements are i...
Introduction Contd Maps play a vital role in the presentation and assessment of the local flood situation. They provide in...
The Study Area Delta State lies approximately between longitudes 5°00 and 6°45E and latitudes 5°00 and 6°30N              ...
Figure 1: Study Area                       6
MATERIALS AND METHODS To determine the vulnerability of the entire state to flooding, Digital Elevation Model (DEM) coveri...
MATERIALS AND METHODS The DEM was classified into three vulnerability classes, using the variation in elevation values Vis...
MATERIALS AND METHODS The Multi-Resolution Land Characterization regional and land cover classification (MRLC) system (Vog...
MATERIALS AND METHODS The risk map of the study area was generated from the ASTER image The categories are highly vulnerab...
MATERIALS AND METHODS It was observed that the flooding of the River Niger affected communities as far as 5 kilometer from...
Figure 2: Digital Elevation Model of Delta State   12
Figure 3: Flood Map of Delta State                                     13
Figure 4: Flooded Farmland                             14
Figure 5: Flooded Settlements                                15
An area of over 7,950km2 or over 49% of the coastaland riverine communities of the State was inundated.This affected about...
Conclusion and Recommendation Remote Sensing and Geographic Information Systems techniques were adopted in examining the e...
Conclusion and Recommendation The results of the study indicate that a large part of coastal and riverine communities in t...
Conclusion and Recommendation This implies that climate change has far-reaching implications on agriculture, food security...
Conclusion and Recommendation This situation is likely to result in increased threat of hunger and malnutrition in the are...
Thank You!!              21
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Spatial analysis of flooding in delta state,Nigeria

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Spatial analysis of flooding in delta state,Nigeria

  1. 1. G.O. Enaruvbe & G.U. YesufRegional Centre for Training in Aerospace Surveys (RECTAS) Obafemi Awolowo University, Ile-Ife, Nigeria 1
  2. 2. Introduction Flood disasters are among the most destructive natural disaster in history. Flooding has become more prevalent over the past decades in Nigeria. The recent incidence of flood disaster in the country has been attributed to increased rainfall and infrastructure failure. 2
  3. 3. Introduction Contd Coastal farming communities are the most adversely affected as their farms and fishing implements are inundated or washed away by the floodwater An important aspect of flood disaster management is the provision of timely information, necessary for mitigation of the impact of the disaster. 3
  4. 4. Introduction Contd Maps play a vital role in the presentation and assessment of the local flood situation. They provide information for flood management strategies Research indicates that the integration of Remote Sensing and Geographic Information Systems (GIS) provide valuable spatial information in the event of a natural disaster 4
  5. 5. The Study Area Delta State lies approximately between longitudes 5°00 and 6°45E and latitudes 5°00 and 6°30N 5
  6. 6. Figure 1: Study Area 6
  7. 7. MATERIALS AND METHODS To determine the vulnerability of the entire state to flooding, Digital Elevation Model (DEM) covering the entire state generated from ASTER image. The scenes covering Delta State were mosaicked within ArcGIs software environment, and transformed to the projected coordinate system -WGS 1984 UTM Zone 32N 7
  8. 8. MATERIALS AND METHODS The DEM was classified into three vulnerability classes, using the variation in elevation values Visual image interpretation and on-screen digitising was used in extracting the land use land cover of the state from medium resolution images derived from Google Earth Their non-spatial characteristics and spatial extent were also determined 8
  9. 9. MATERIALS AND METHODS The Multi-Resolution Land Characterization regional and land cover classification (MRLC) system (Vogelmann et al. 1998) is adopted in categorizing the land use types in the entire state On the basis of the MRLC classification systems, the state is classified into four major land use classes (Waterbody, Settlement, Bare surface and Vegetated surface). 9
  10. 10. MATERIALS AND METHODS The risk map of the study area was generated from the ASTER image The categories are highly vulnerable, vulnerable and non-vulnerable areas. A field survey of areas affected by the flood was conducted in order to assess the extend of the flood 10
  11. 11. MATERIALS AND METHODS It was observed that the flooding of the River Niger affected communities as far as 5 kilometer from the River banks A buffer of 5km was therefore created for River Niger and its major tributaries and 2km for minor distributaries 11
  12. 12. Figure 2: Digital Elevation Model of Delta State 12
  13. 13. Figure 3: Flood Map of Delta State 13
  14. 14. Figure 4: Flooded Farmland 14
  15. 15. Figure 5: Flooded Settlements 15
  16. 16. An area of over 7,950km2 or over 49% of the coastaland riverine communities of the State was inundated.This affected about 39 communities and over 137.1hectares of farmland across the State 16
  17. 17. Conclusion and Recommendation Remote Sensing and Geographic Information Systems techniques were adopted in examining the extent and impact of the recent flood disaster on agriculture and human settlement in the study area The use of ASTER images for the generation of DEM seems effective in mapping flood prone areas in the State 17
  18. 18. Conclusion and Recommendation The results of the study indicate that a large part of coastal and riverine communities in the State are affected by the flood, inundating many farmlands and washing away fishing equipment 18
  19. 19. Conclusion and Recommendation This implies that climate change has far-reaching implications on agriculture, food security and social stability in the Niger Delta as food prices are likely to skyrocket as a result of low agricultural productivity and food scarcity 19
  20. 20. Conclusion and Recommendation This situation is likely to result in increased threat of hunger and malnutrition in the area Since flooding is aggravated by obstruction to natural water channels it is important that urban and regional development plans be rigorously pursued and implemented to avoid a situation where buildings and other structures are constructed on natural drainages 20
  21. 21. Thank You!! 21

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