Characterization and Classification of Soils of Rigachikun- Kaduna, Northern Guinea Savanna, Nigeria

This research was carried out at Rigachikun, a Northern Guinea Savanna region of Nigeria and aimed at characterizing and classifying the soils of the region to generate soil information resources that will provide guide in the utilization of the soils of the region. With the aid of a location map, soils were delineated into three locations A, B and C and three profile pits were dug in each location giving a total of nine (9) profile pits. The morphological properties of the studied soils show that the grade of structure ranged from weak at the surface to strong down the horizon in all studied locations A, B and C. Soil colours at location A ranged from 2.5 YR 6/3 (light reddish brown) to 2.5 YR 5/6 (red) in pedon 1, 2.5YR 4/4 (reddish brown) to 2.5YR4/8 (red) in pedon 2 and 2.5YR 4/2 (weak red) to 2.5YR 4/6 (red). Location B colour matrixes ranged thus, pedon 1; from 2.5YR ¾ (dark reddish brown) to 2.5YR 3/6 (dark red), pedon 2; 2.5YR 5/2 (weak red) - 2.5YR 3/6 (dark red) while Pedon 3; 2.5YR 3/2 (dusky red) to 2.5YR 3/6 (dark red). Textural properties show that in location A, clay increased in all pedons and silt decreased while sand showed no clear pattern although it ultimately decreased down the profile. In location B; clay also increased down the profile in all pedons investigated, silt decreased in pedons 1 and 3 while it has no clear distribution in pedon 2. Sand however decreased in all pedons of location B. In Location C; clay and silt increased while sand decreased in pedons 1 and 2. In pedon 3, clay increased, sand decreased while silt has no particular pattern of distribution. The coefficient of variation showed that clay and silt ranged mostly from moderate (CV>15≤ 35) to high variation (CV > 35) except in location A pedon 3, location B pedons 1 and 2; Location C pedons 1, 2 and 3 where silt had low variability (CV≤ 15). Location A pedons 1 and 2 were classified as Typic Durustepts while pedon 3 is Aridic Lithic Haplustepts. Location B pedons 1, 2 and 3 were classified as Arenic Aridic Kandiustults while location C pedons 1,2 and 3 were classified as Aridic Kandiustults.