TITLE:
Short Term Leguminous Trees-Tillage Interactions and Their Effect on Soil-Water Content in a Semi-Arid Agroforestry Parkland
AUTHORS:
Chester Kalinda, David Mburu, Kamau Ngamau, Lwali A. Chisala, Donald Zulu, John Kihoro
KEYWORDS:
G. sepium, F. albida, T. candida, Leguminous Tree Species, Soil Organic Carbon, Soil Water Retention, Infiltration
JOURNAL NAME:
Open Journal of Forestry,
Vol.5 No.7,
September
22,
2015
ABSTRACT: Agricultural activities that encourage slashing, burning and ploughing
greatly affect the soil structure and soil organic matter on which soil water
retention depends. In this study, we hypothesized that inclusion of rotational leguminous tree species improves
soil water retention in a semi-arid conservation agriculture system. In a study
done in Kibwezi, semi-arid eastern Kenya, results showed that the amount of
water retained in the different soil strata from plots with different tree
species and tillage practices was highly significant (P = 0.032). Plots with planting basins and Gliricidia sepium and Faidherbia
albida tree species retained more water in both the upper and lower strata.
Plots with G. sepium tree species
under planting basins and zero tillage under F. albida had significantly higher soil organic carbon levels than
plots that were managed under ridges and ploughing (P = 0.002). On the other hand, bulk density in plots with planting basins and zero tillage
and ridges ranged between 1.35 g/cm3 and 1.53 g/cm3.
Conventional tillage plots had bulk density values of 1.65 g/cm3 and
1.72 g/cm3 in the upper and lower strata respectively. The time-dependent
nature of rotational leguminous tree species on soil organic matter and soil
water retention in the semi-arid conservation agriculture system highlights the
importance of considering these species for improving organic carbon and water
retention for improved crop production.