Biomass estimation using Landsat-TM and -ETM+. Towards a regional model for Southern Africa?

Grazing and fire are major factors influencing the savanna ecosystems of Southern Africa. In both grazing and conservation areas overgrazing is an important reason for degradation of vegetation and soil. Insufficient fire management can cause a change in the species composition and may influence the soil negatively. For adequate planning purposes the knowledge of available biomass is indispensable. High-resolution satellite systems can provide such knowledge on a large scale. Three study areas in Southern Africa contributed to a first survey. Gutu District is situated in Zimbabwe. In its Communal Lands a high population density leads to severe degradation of vegetation and soil. The South African test sites are located in Kruger National Park and Madikwe Game Reserve. Therefore a wide ecological range from highly degraded to slightly disturbed savanna ecosystems is included. Satellite images of both Landsat-5 (TM) and Landsat-7 (ETM+) were applied. After cross-calibration of the two different satellite systems, indices applied to radiance and reflectance showed significant correlations with ground truth data of grass and other foliage biomass. Including new data from Hluhluwe National Park (South Africa) into the regression models improved the results, indicating that a regional model for savanna ecosystems in Southern Africa could be found.

[1]  H. C. Hanson,et al.  An Agricultural Survey of Southern Rhodesia. Part I. Agro-Ecological Survey , 1962 .

[2]  D. H. Knight,et al.  Aims and Methods of Vegetation Ecology , 1974 .

[3]  M. Rutherford,et al.  Survival, regeneration and leaf biomass changes in woody plants following spring burns in Burkea africana—Ochna pulchra Savanna* , 1981 .

[4]  B. Huntley.  Southern African Savannas , 1982 .

[5]  The potential of Landsat MSS data for wood resources monitoring : a study in arid and semi-arid environment in Kordofan, the Sudan , 1982 .

[6]  C. Tucker,et al.  Satellite remote sensing of total dry matter production in the Senegalese Sahel , 1983 .

[7]  J. Leonard,et al.  The Vegetation of Africa , 1984 .

[8]  K. Olsson.  Remote sensing of woody vegetation : a quantitative approach in the Sudanese drylands , 1984 .

[9]  Ghassem R. Asrar,et al.  Estimation of total above-ground phytomass production using remotely sensed data , 1985 .

[10]  Compton J. Tucker,et al.  Satellite remote sensing of total herbaceous biomass production in the Senegalese Sahel - 1980-1984 , 1985 .

[11]  Blaine L. Blad,et al.  Evaluation and interpretation of Thematic Mapper ratios in equations for estimating corn growth parameters , 1985 .

[12]  Ray D. Jackson,et al.  Winter wheat vegetation indices calculated from combinations of seven spectral bands , 1985 .

[13]  W. Trollope,et al.  Estimating grass fuel loads with a disc pasture meter in the Kruger National Park , 1986 .

[14]  Alan H. Strahler,et al.  Invertible canopy reflectance modeling of vegetation structure in semiarid woodland , 1988 .

[15]  Ghassem R. Asrar,et al.  Theory and applications of optical remote sensing. , 1989 .

[16]  J. Everitt,et al.  Estimating grassland phytomass production with near-infrared and mid-infrared spectral variables , 1989 .

[17]  R. Whitlow,et al.  Factors influencing erosion in Zimbabwe: a statistical analysis , 1989 .

[18]  Janet Franklin,et al.  Estimating foliage and woody biomass in Sahelian and Sudanian woodlands using a remote sensing model , 1991 .

[19]  R. Jackson,et al.  Multisite Analyses of Spectral-Biophysical Data for Wheat , 1992 .

[20]  M. Chenje,et al.  State of the Environment in Southern Africa , 1994 .

[21]  D. Ward,et al.  Fuel biomass and combustion factors associated with fires in savanna ecosystems of South Africa and Zambia , 1996 .

[22]  B. Campbell.  The miombo in transition: woodlands and welfare in Africa. , 1996 .

[23]  Use of image processing and GIS techniques to determine the extent and possible causes of land management/fenceline induced degradation problems in the Okavango area, northern Botswana , 1997 .

[24]  W. D. Plessis.  Refinements to the burning strategy in the Etosha National Park, Namibia , 1997 .

[25]  Harry Biggs,et al.  Trends in woody vegetation cover in the Kruger National Park, South Africa, between 1940 and 1998 , 2000 .

[26]  J. L. Barker,et al.  Radiometric cross-calibration of the Landsat-7 ETM+ and Landsat-5 TM sensors based on tandem data sets , 2001 .

[27]  Wolter Arnberg,et al.  Assessment of vegetation indexes useful for browse (forage) prediction in semi-arid rangelands , 2001 .

[28]  Limin Yang,et al.  Derivation of a tasselled cap transformation based on Landsat 7 at-satellite reflectance , 2002 .

[29]  Cyrus Samimi,et al.  BIOMASS ESTIMATION FOR LAND USE MANAGEMENT AND FIRE MANAGEMENT USING LANDSAT-TM AND -ETM+ , 2002 .

[30]  B. Markham,et al.  Revised Landsat-5 TM radiometric calibration procedures and postcalibration dynamic ranges , 2003, IEEE Trans. Geosci. Remote. Sens..