Kamalu O. J1. and Orji O. A.2
1Crop and Soil Science Department, University of Port Harcourt, Port Harcourt P.M.B.5323 Port Harcourt
2Crop/Soil Science Department, Rivers State University Nkpolu-Oruworukwo, Port Harcourt
IOSR Journal of Agriculture and Veterinary Science (IOSR-JAVS) e-ISSN: 2319-2380, p-ISSN: 2319-2372. Volume 11, Issue 3 Ver. II (March 2018), PP 01-11
Abstract:
This paper evaluates the potentials and vulnerability of the Sombreiro Warri Deltaic Plain soils using physical properties. A total of 52 genetic horizon soil samples were studied in twelve soil profiles located in Akabuka, Obite, Obagi, Omoku, Okwuzi, Aggah and Umuoru-Ndoni areas. The soils have predominantly Loamy sand and sandy loam textures on the surface (about 80% of all the studied locations). Sand content had a range of 220 – 850g/kg with a mean of 515g/kg. Clay content in the area varied from 140 – 580g/kg, with a very gradual increase with depth in few pedons. The highest clay content was observed in the Umuoru / Ndoni 2 profile where clay had a range of 470 – 580g/kg followed by Umuoru/Ndoni 1 profile with a range of 210 – 270g/kg and a mean of 245g/kg. The range in particle density for the soils was 2.10 – 2.66gcm-3. The highest profile mean particle densities were 2.53, 2.50 and 2.43gcm-3 for Umuoru/Ndoni 2, Aggah 2 and Umuoru 1 respectively while the lowest mean values were Obite 1 (2.33), Akabuka 2 (2.33) and Obagi 1 (2.30gcm-3). About 50% of the soils had their particle density between 2.35 and 2.46gcm-3. The lowest mean values for different pedons were obtained in Umuoro/Ndoni, Obiafu and Aggah pedons with 1.38, 1.42, 1.43 and 1.44gcm-3 respectively while the highest relatively higher values of 1.61, 1.62 and 1.64gcm-3 were obtained in Obite 1, Obagi 1 and Obagi pedons respectively. Surface horizons generally had lower bulk density values in most of the pedons. Aggregation in macro aggregate fraction was high in Obagi II, Omoku 1 and Okwuzi. Aggregate stability was low with Mean Weight Diameter (MWD) of water stable aggregates of 1.64, 1.36, and 1.23mm for Obagi II, Omoku 1 and Okwuzi respectively. Topsoil and subsoil permeability were very slow ranging from 4.92cmhr-1 to 14.18cmhr-1. Mean soil permeability in the profiles were 4.81, 1.28, 8.66, 1.29 and 0.65cmhr-1 for Obite 1, Obrikom, Obagi 2 and Obuburu, respectively.
Keywords: Soil permeability, macro-porosity, Water stable aggregates, Water holding capacity, Soil Vulnerability