Regreening the Sahel and Farmer Managed Natural Regeneration: What the Satellite Imagery Shows

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2 Regreening the Sahel and Farmer Managed Natural Regeneration: What the Satellite Imagery Shows First Drylands Week June 10-17, 2011 Dakar, Senegal Gray Tappan, U.S. Geological Survey Earth Resources Observation and Science (EROS) Center Sioux Falls, South Dakota USA U.S. Department of the Interior U.S. Geological Survey

3 The U.S. Geological Survey s Earth Resources Observation and Science (EROS) Center s vision is to be the world s leading source of land information for exploring our changing planet.

4 Many thanks for funding and support: U.S. Agency for International Development CILSS (Permanent Interstate Committee for Drought Control in the Sahel) African Regreening Initiative Centre de Suivi Ecologique, Senegal Institut des Sciences de l Environnement (ISE/UCAD), Senegal

5 Challenges in Monitoring Agro-Environmental Transformations Farmers don t tell you when they ve made land improvements Biophysical changes occur on a vast geographic scale Distinguishing climate versus anthropogenic factors is complicated Visual evidence of benefits often not apparent in less than 3-4 years; Significant biophysical changes may take a decade or more Time-series mapping of land cover is technically challenging

6 Remote Sensing: A Definition Remote sensing is the science and art of acquiring information about the Earth s surface without being in physical contact with it. Image Courtesy of NASA: SeaWiFs

7 Remote Sensing Advantages Synoptic perspective Unique vantage point Extra-visual information Historical and permanent record Image Courtesy of NASA: SeaWiFs

8 Remote sensing systems that provide coverage of West Africa Meteosat SeaWIFS MODIS SPOT Vegetation NOAA-AVHRR Landsat Corona ASTER SPOT 5 IKONOS Quickbird Historical Aerial Photography Recent Aerial Photography Aerial Videography SeaWIFS Image

9 Approach to Mapping, Monitoring, and Modeling LULC *Levels of Data Collection Satellite level Aerial level Ground level *All data collected through time

10 Field Data Collection: Dicrostachys glomerata

11 Permanent Monitoring Sites in Senegal (Established in )

12 Field Data Collection: Determining vegetation structure for mapping Species-level inventories to monitor biodiversity Biomass and carbon measurements

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16 Revisited Ground Sites to Document Changes in Natural Resources

17 Monitoring on-farm trees in the Peanut Basin: 28-year comparison Jan 1983 Feb 2011

18 Protection of an ecosystem: (Niokolo-Koba, Senegal) Woody Species at Site 487: Bombax costatum Annona senegalensis Combretum crotonoides Combretum geitonophyllum Combretum glutinosum Combretum micranthum Combretum nigricans Crossopterix febrifuga Danielia oliveri Detarium microcarpum Gardenia erubescens Hexalobus monopetalus Hymenocardia acida Lannea acida Ostryoderris stuhlmannii Piliostigma thonningii Pterocarpus erinaceus Stychnos spinosa Terminalia avicennioides Terminalia macroptera Vitex madiensis Ximenia americana Cordyla pinnata Entada africana Sterculia setigera 2007 Bombax costatum Annona senegalensis Combretum crotonoides Combretum geitonophyllum Combretum glutinosum Combretum micranthum Combretum nigricans Crossopterix febrifuga Danielia oliveri Detarium microcarpum Gardenia erubescens Hexalobus monopetalus Hymenocardia acida Lannea acida Ostryoderris stuhlmannii Piliostigma thonningii Pterocarpus erinaceus Stychnos spinosa Terminalia avicennioides Terminalia macroptera Vitex madiensis Ximenia americana Cordyla pinnata Entada africana Sterculia setigera 2007

19 Aerial Surveys with the Centre de Suivi Ecologique (CSE)

20 A powerful combination: Airplane, GPS and a camera

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22 Landsat Image: Mangroves, Protected areas, and Cropland

23 Mapping and Monitoring: The Senegal Experience Mapped the Land Resources of Senegal ( ) Monitored land cover trends with CSE through four decades (completed in 1999) Built on results for quantifying carbon stocks in soils and vegetation (completed in 2003) Currently assessing and mapping land resources in the Kedougou and Casamance Regions

24 Published Vegetation Map of Senegal (1986)

25 Soils of Senegal

26 Seasonal Vegetation Patterns NOAA-AVHRR NDVI (vegetation index or greenness)

27 Satellite observed greening trend Trends in NDVI corrected for the effects of rainfall: Source: Herrmann et al., 2005

28 Tree Parkland Dominated by Faidherbia albida: Leaf-off Stage in the Rainy Season

29 Enlargement from a Landsat Image, October 2000: Tree parklands not visible (south of Aguié, Niger) 0 5 km

30 Niger Land Cover in 1975

31 Niger Land Cover in 2000

32 Southern Niger in the 1980s

33 Southern Niger in 1997: Early Evidence of FMNR

34 Preparing for flight at Tahoua, Niger

35 Tahoua Region, Niger in 2005: Well established FMNR

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38 Parkland Renaissance: trees are young and growing

39 Agricultural Parkland east of Matamèye

40 Impact of trees on crop growth

41 Impact of a single F. albida tree on crop growth (radius of high productivity: 5 m around a small tree)

42 Quickbird Image of Medium Density Tree Parkland East of Maradi, Oct. 2005

43 1955 Landscape Dynamics Southwest of Zinder

44 1955 Landscape Dynamics Southwest of Zinder

45 Percent Tree Cover Trend in the Study Area (Mirria-Magaria-Matameye Triangle)

46 General Extent of Farmer-Managed Natural Regeneration

47 Is It Increased Rainfall?

48 More People More Trees Population

49 Location of 12 Terroirs Used for Comparing Tree Density Across the Niger-Nigeria Border Tahoua Niger Maradi Nigeria Zinder Terroirs km

50 Terroir in Niger 19 km North of the Niger-Nigeria Border Source: Source: Google Google Earth, Earth,

51 Terroir in Niger 8.5 km North of the Niger-Nigeria Border Source: Google Earth, 2005

52 Terroir in Nigeria 1.5 km south of the Niger-Nigeria Border Source: Google Earth, 2005

53 Terroir in Nigeria 38 km south of the Niger-Nigeria Border Source: Google Earth, 2005

54 Comparative Overview of Terroirs on Opposite Sides of the Niger-Nigeria Border Source: Google Earth, 2005 Niger Nigeria

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56 What is the overall extent and density of FMNR in southern Niger? Quickbird image south of Zinder

57 Extent and Density of Tree Cover Across Southern Niger

58 Maerua crassifolia

59 Benefits of On-Farm Trees a Win-Win Strategy Firewood production Fodder for animals Increase biodiversity Habitat for millions of migrating birds Fruit production Traditional medicine Increased soil fertility Decreased soil erosion Reduced wind speed Increased crop yields Increased water infiltration Decrease in temperature Increase in rainall Inexpensive and easy to adopt Increase in biomass and carbon Contribute to mitigating climate change

60 Senegal land cover in 1975

61 Senegal land cover in 2000

62 Mature Faidherbia albida Parkland: N. of Khombole, Peanut Basin, Senegal

63 Mature Faidherbia albida Parkland: 32 T Carbon / ha Peanut Basin, Senegal

64 Tree Parkland Dominated by Faidherbia albida: Leaf-off Stage in the Rainy Season (N. of Khombole)

65 Permanent Monitoring Sites in Senegal (Established in )

66 Monitoring on-farm trees in Senegal Peanut Basin, 20-year comparison Site

67 Monitoring on-farm trees in the Peanut Basin: 28-year comparison Jan 1983 Feb 2011

68 Monitoring on-farm trees in the Peanut Basin Feb 1998 Jan 2011

69 Monitoring on-farm trees in the Peanut Basin: 15-year comparison Nov 1995 Jan 2011

70 Soil Susceptibility to Wind Erosion

71 Very low tree density in the Saloum

72 Monitoring on-farm trees in Senegal: 27-year comparison May 1983 Site 581: Dépt. de Kaffrine Mar 2010

73 Monitoring on-farm trees in the Saloum, Senegal Jan 1994 Dec 2004

74 Senegal s Agricultural Parkland Region and Potential Directions of Expansion to other Agricultural Regions Agriculture areas Represented in yellow Main parkland area Outlined in green

75 Faidherbia albida trees in rice fields, Basse Casamance, Senegal

76 Final Remarks Time-series remote sensing imagery played a key role in characterizing the extent and magnitude of agroenvironmental transformations High resolution imagery provides a practical way to monitor FMNR Time-series images helped convince people that a positive landscape changes were happening at a grand scale Remote sensing provides a baseline from which to monitor the spread, uptake and impacts of FMNR

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