Evaluation of Phosphorus Fixation Capacity South Eastern Nigerian Soils.

ABSTRACT

It is generally believed that tropical soils fix most phosphorus (P) applied as fertilizer into forms not available to plants. To study the fixation capacity of soils in south eastern Nigeria, 10 samples gotten from Umudike, Akwete, Ohafia, Owerri, Bonny, Okigwe, Afikpo, Nsukka and Ogoja were used and soil which were found to vary in cropping histories, physical and chemical properties and derived form various parent materials and were evaluated for capacities to fix soluble P with time. The method used in this study involved the incubation of the soils for one day, liy 30 days, 60 days and 100 days respectively after which 5g of each soil sample was shaken using Bray P1 extracting (0.0.N NH4F + 0.025 N HCL). The P recovery, fixed P and fertilizer factor of the soils were calculated. From the P recovery chart graphs were drawn from where the fractional recovery which is the slope of the graphs was determined. The fractional recovery was noticed to decrease with time following a pattern of rapid decline during the first few days of incubation and a slower decline thereafter. Bonny soils with a value of 6% had the least fractional recovery while Afikpo soils had the highest fractional recovery with a value of 61%.The results obtained showed rapid fixation at the first day of incubation accounting for more than 40% of the applied P after which was a gradual decrease in fixation rate. The results also indicate high P fixation rate characteristics of the highly weallJ soils of the zone.

 TABLE OF CONTENTS

Page Tittle

Certification

Acknowledgment ii

Dedication

Title Page iv

Table of Content V

List of Table Vi

List of Figures Vii

Abstract Vii

1.0 Introduction 1

2.0 Literature Review 3

3.0 Materials and Methods 9

4.0 Results and Discussion 13

5.0 Summary and Conclusion 24

6.0 Reference 25