Evaluation of agro-ecological approach to soil quality assessment for sustainable land use and management systems

Abstract

Long-term cultivation of crops has been found to cause soil physico-chemical and biological quality (SQ) degradation for sustainable agricultural production practices in Akwanga, Nigeria. Understanding the dynamics of SQ change under different land use types is desired. The present study was carried out to assess soil physico-chemical indicators (based on land evaluation approach) and biological SQ (based on agro-ecological approach) for sustainability of cereal, arable and plantation land uses and management systems. Quantitative and qualitative indicators were defined based on chronosequence of soils under different land use types: 3-month cereal cropping of Rice; 7-month root cropping (yam/cassava/vegetable intercrop); 10-year plantation (orange/pineapple orchard); and >22-year oil palm plantation. Their respective management practice is Tillage + NPK fertilization; Tillage + NPK fertilizers + Organic manure; No tillage + mulch; and no tillage + Farm yard manure + Legume cover as live mulch. Each age cla s was replicated at least three times and their sensitivity to change was sought. The statistical mean values of the bio-physical and chemical properties of soil quality indicators (SQI) under the various types of land use (LUT) show that the most sensitive soil quality indicators ( P P P