| Autor: |
Balla, M. K.1 iofballa@fewanet.com.np, Awasthi, K. D.1, Singh, B. R.2, Sitaula, B. K.3, Pradhan, B. M.1 |
| Předmět: |
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| Zdroj: |
International Journal of Ecology & Environmental Sciences. Sep2007, Vol. 33 Issue 2/3, p171-182. 12p. 6 Diagrams, 2 Charts. |
| Abstrakt: |
Land use changes over the period I 978 to 1992 and 1992 to 2004 and geomorphometric characteristics (hypsometric curve, hypsometric integral, drainage density and length of overland flow) were investigated to analyse the susceptibility of Galaundu and Pokhare Khola watersheds, Dhading district, mid-mountain region of Nepal to surface erosion and soil degradation. The study used air photo interpretation of 1978 and 1992 and remote sensing imagery (Landsat TM of 2002) interpretation and hypsometric analyses using geographic information system (GIS) techniques. Land use change analyses show a decrease mainly in rainfed upland (Ban) and forest but an increase in irrigated paddy land (Khet) and shrub during the period 1978 and 1992. Increase in Khet and shrub land and continued decrease in Ban, mainly due to conversion to Khet have been observed during 1992 to 2004. Hypsometric curves and integrals were found to be concave in shape and of low values (0.48 and 0.50 for Galaundu and Pokhare respectively) indicating that both watersheds are at the deteriorating stage. Drainage densities of 5. I and 5.14 for Galaundu and Pokhare respectively are low with corresponding values of long lengths of overland flow (98 and 97 m) which make both watersheds vulnerable to soil erosion and land degradation. [ABSTRACT FROM AUTHOR] |
| Databáze: |
GreenFILE |
| Externí odkaz: |
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