ANALYSIS OF SPATIO-TEMPORAL PATTERNS OF HYDRO-GEOMORPHIC SENSITIVITY AREAS AND DESERTIFICATION STATUS IN A PART OF BORNO-YOBE SEMI-ARID ZONE OF NIGERIA
Abstract
The major goal of this study is to monitor spatio-temporal patterns of hydro-geomorphic sensitivity indicators to depict desertification status in the semi-arid zone of Nigeria over a period of 30 years (1987-2016).Four specific hydro-geomorphic indices; Topographic Wetness Index (TWI), Stream Power Index (SPI), Sediment Transport Index (STI) and Normalised Difference Water Index (NDWI), were evaluated and mapped into raster layers using appropriate algorithm on the Digital Elevation Model (DEM). These indicators represent soil moisture, surface run-off erosivity, soil erosion and surface water distribution respectively which represent the key hydro-geomorphic forms and processes of desertification. The MEDALUS (ESA) approach was applied to aggregate specific temporal indices into single component index; TWSI, SPSI, STSI NDWSI respectively and the four into the Hydro-geomorphic Sensitivity Index (HgSI). These respective indices were further segmented and mapped into five sensitivity areas and to determine their mean extents; Very High (VH), High (H), Moderate (M), Low (L) and Very Low (VL) based on natural jenks method. The five hydro-geomorphic sensitivity classes were validated based on post classification field reconnaissance to interpret the corresponding landscape as follows; Very High (upslope catchment area with sparse shrubs), High (upslope catchment area with patchy dense shrubs), Moderate (light riparian/woody savanna), Low (wetland/floodplain/dense woody savanna) and Very Low (Broad river/Water bodies/Oases) respectively. Results showed average extents of Hydro-geomorphic sensitivity classes for the 30373 km2 study area for the period as follows; VH: upslope catchment with sparse shrubs (6532 km2), H: upslope catchment with dense shrubs (11521 km2), M: Riparian/forest/woody savanna (5643 km2),
References
Aguiar M.R., and O.E. Sala. (1999). Patch structure, dynamics and implications for the functioning of arid ecosystems. Trends Ecol. (14): 273-277.
Ati, O.F. (2006). Rainfall characteristics in drought prone sudano-sahelian zone of Nigeria.Unpublished Ph.D thesis, Department of Geography Ahmadu Bello University, Zaria.
B´argossy, A. and Lehmann, W. (1998). Spatial distribution of soil moisture in a small catchment. Part 1: geostatistical analysis, Journal of Hydrology, (206): 1–15.
Beven, K. and Kirkby, M. J. (1979). A physically based, variable contributing area model of basin hydrology, Hydrological Sciences Bulletin, 24(1): 43–69.
Burt, T and Butcher, D (1986). Stimulation from simulation- a teaching model of hillslope hydrology for use as microcomputer. Journal of Geography and Higher Education, (10): 23-39.
Conacher, A.J and Sala, M. (1998). Land degradation in mediterranean environments of the world: nature and extent, causes and solutions. Wiley and Sons.
Hjerdt K N, McDonnell J J, Seibert J and Rodhe A 2004 A new topographic index to quantify downslope controls on local drainage; Water Resour. Res. 40(5):5602.
Huang B and Jiang B (2002). A full integration of TOPMODEL into GIS; Environ. Modelling & Software (17): 261–268.
Huenneke LF, Schlesinger WH. (2004). Patterns of net primary production in Chihuahuan desert ecosystems. In Structure and Function of a Chihuahuan Desert Ecosystem: The Jornada Basin Long-term Ecological Research Site, Havstad KM, Huenneke LF, Schlesinger WH (eds). Oxford University Press: Oxford; 232–246, 492.
Hooke JM (2006). Human impacts on fluvial systems in the Mediterranean region. Geomorphology 79:311–335
Imeson AC, Lavee H, (1998). Soil erosion and climate change: the transect approach and the influence of scale. Geomorphology 23: 219–227.
Jenks, G. F. (1967). The data model concept in statistical mapping, International Yearbook of Cartography (7): 186–190.
Jenks, G. F. (1977). Optimal data classification for choropleth maps, Occasional paper No. 2. Lawrence, Kansas: University of Kansas, Department of Geography
Kosmas, C., Kirby, M., Geeson, N., (1999). The MEDALUS project: Mediterranean desertification and land use. Manual on Key Indicators of Desertification and Mapping Environmentally Sensitive Areas to Desertification European Commission Project ENV4 CT 95 0119 (EUR 18882).
Latron J, Llorens P, Gallart F (2009). The hydrology of Mediterranean mountain areas. Geogr Compass 3(6):2045–2064
Lobell, D. B. and Asner, G. P. (2002). Moisture effects of soil reflectance, Soil Science Society of America Journal, (66): 722–727.
Ludwig J.A., and D.J. Tongway. (1995). Spatial organization of landscapes and its function in semi-arid woodlands, Australia. Landscape Ecol. (10): 51-63.
Ludwig, J.A., and D.J. Tongway. (1996). Rehabilitation of semiarid landscapes in Australia. II. Restoring vegetation patches. Restor. Ecol. 4: 398-406.
Maestre, F.T., James F. Reynolds, J., Huber-Sannwald, E., Herrick, J., and Stafford-Smith, M. (2006). Understanding Global Desertification: Biophysical and Socioeconomic Dimensions of Hydrology. P. D’Odorico and A. Porporato (Eds.), Dryland ecohydrology 315-332 Springer, Netherlands.
Ndabula C., Averik P. D., Jidauna G.G.,Abaje I., Oyatayo T. K., Iguisi, E. O (2013) . Analysis of the Spatio-Temporal Dynamics of Landuse/ Landcover Stuctures in the Kaduna Innercore City Region, Nigeria, American Journal of Environmental Protection, 1( ): 112-119. http://pubs.sciepub.com/env/1/4/7
Ndabula, C. (2015). Spatio-temporal patterns of biophysical indicators of desertification status in the Borno-Yobe area of Nigeria. Unpublished Ph.D thesis in the department of geography, Ahmadu Bello University, Zaria.
regimes at Muooni Dam site, Machakos District, Kenya. Masters Thesis. Nairobi, Kenya, Kenyatta University, School of Pure and Applied Sciences
Oladipo, E.O. (1994). Some aspects of the spatial characteristics of drought in northern Nigeria. Natural Hazards (8): 171-188.
Pla, I. (2005. Hydrological approach for assessing desertification processes in the Mediterranean Region. In: “Desertification in the Mediterranean Region: A Security Issue”. NATO Security Science C. Vol 3. Springer.
Heidelberg (Germany). (ISBN 1-4020-3758-9)
Porporato A, Rodriguez-Iturbe I. 2002. Ecohydrology-a challenging multidisciplinary research perspective. Hydrological Sciences Journa (47): 811–821.
Puigdefábregas J., A. Solé-Benet, L. Gutiérrez, G. Del Barrio, and M. Boer. (1999). Scales and processes of water and sediment redistribution in drylands: results from the Rambla Honda field site in Southeast Spain. Earth-Sci. Rev. (48): 39-70.
Quinn P F and Beven K (1993). Spatial and temporal predictions of soil moisture dynamics, runoff, variable source areas and evapotranspiration for Plinlimon, Mid-Wales; Hydrol. Proces. (5): 59–79.
Raaflaub L D and Collins M J (2006). The effect of error in gridded digital elevation models on the estimation of topographic parameters; Environmental Modelling & Software (21): 710–732.
Reynolds J.F., P.R. Kemp, K. Ogle, and R.J. Fernández. (2004). Modifying the “pulse-reserve” paradigm for deserts of North America: precipitation pulses, soil water, and plant responses. Oecologia 141: 194-210.
Reynolds, J.F., and D. M. Stafford Smith, editors. (2002b). Global Desertification: Do Humans Cause Deserts? Berlin: Dahlem University Press.
Reynolds, J.F., R.A. Virginia, and W.H. Schlesinger. 1997. Defining functional types for models of desertification. In: Plant Functional Types: Their Relevance to Ecosystem Properties and Global Change, T.M. Smith, H.H. Shugart, and F.I. Woodward, eds. Cambridge University Press, Cambridge, 194-214.
Rodriguez-Iturbe I. (2000). Ecohydrology: a hydrologic perspective of climate-soil-vegetation dynamics. Water Resources Research (36): 3–9.
SeghieriJ., and S. Galle. 1999. Run-on contribution to a Sahelian two-phase mosaic system: Soil water regime and vegetation life cycles. Acta.Oecol. 20: 209-217.
Sharma K.D. 1998. The hydrological indicators of desertification. J. Arid Environ. 39:121-132.
Tombul M 2007 Mapping field surface soil moisture for hydrological modeling; Water Resour. Manag. 21(11) 1865–1880.
Turnbull, L., Wainwright, J., Brazier, R.E., 2008. A conceptual framework for understanding semi-arid land degradation: ecohydrological interactions across multiple-space and time scales. Ecohydrology 1 (1), 23–34.
United Nations Environment Programme, UNEP. (Ed). 2000. Global environmental outlook: past, present and future perspectives. Available at: www.unep.org/GEO-2000/
von Hardenberg J., E. Meron, M. Shachak, and Y. Zarmi. 2001. Diversity of vegetation patterns and desertification. Phys. Rev. Lett. (87): 198101-1-198101-4.
Wang Y, (2010). Typical agricultural areas of China _Dezhou city’s structure changes based on past Decade data. Journal of geography and geology Vol. 2(1):93-97
Whitford W. G. (2002). Ecology of desert systems. London: Academic Press.
Zinko U, Seibert J, Dynesius M and Nilsson C (2005). Plant species numbers predicted by a topography-based groundwater flow index; Ecosystem ,8(4): 430–441.
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