Premium
Erodibility in relation to water‐dispersible clay for some soils of eastern Nigeria
Author(s) -
Igwe C. A.
Publication year - 2005
Publication title -
land degradation and development
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.403
H-Index - 81
eISSN - 1099-145X
pISSN - 1085-3278
DOI - 10.1002/ldr.647
Subject(s) - soil water , dispersion (optics) , soil science , organic matter , cation exchange capacity , saturation (graph theory) , clay minerals , environmental science , soil test , sodium adsorption ratio , environmental chemistry , chemistry , mineralogy , agronomy , mathematics , physics , organic chemistry , drip irrigation , combinatorics , biology , irrigation , optics
Water dispersible clay (WDC) can influence soil erosion by water. Therefore, in highly erodible soils such as the ones in eastern Nigeria, there is a need to monitor the clay dispersion characteristics to direct and modify soil conservation strategies. Twenty‐five soil samples (0–20 cm in depth) varying in texture, chemical properties and mineralogy were collected from various locations in central eastern Nigeria. The objective was to determine the WDC of the soils and relate this to selected soil physical and chemical attributes. The soils were analysed for their total clay (TC), water‐dispersible clay (WDC), clay dispersion ratio (CDR), dispersion ratio (DR), dithionite extractable iron (Fed), soil organic matter (SOM), exchangeable cations, exhangeable sodium percentage (ESP) and sodium adsorption ratio (SAR). Total clay contents of the soil varied from 80–560 g kg −1 . The USLE erodibility K ranges from 0·02 to 0·1 Mg h MJ −1 mm and WEPP K fall between 1·2 × 10 −6 –1·7 × 10 −6 kg s m −4 . The RUSLE erodibility K correlated significantly with CDR and DR ( r = 0·44; 0·39). Also, a positive significant correlation ( r = 0·71) existed between WEPP K and RUSLE K. Soils with high clay dispersion ratio (CDR) are highly erodibile and positively correlates ( p < 0·51) with Fed, CEC and SOM. Also, DR positively correlates with Mg 2+ and SOM and negatively correlate with ESP and SAR. Principal component analysis showed that SAR, Na + and percent base saturation play significant role in the clay dispersion of these soils. The implication of this result is that these elements may pose potential problem to these soils if not properly managed. Copyright © 2005 John Wiley & Sons, Ltd.