Using Pedotransfer Functions (PTFs) to Estimate Soil Water Retention Characteristics (SWRCs) in the Tropics for Sustainable Soil Water Management: Tanzania Case Study

摘要

Direct measurement of SWRCs, important for sustainable soil water management are expensive, time consuming, and labour intensive. To overcome these, PTFs have been developed mainly in the developed temperate countries. The PTFs developed using data from soils found in the temperate countries are directly inapplicable to soils found in the tropics. In this paper PTFs developed in Brazil are tested and new ones developed and tested using data collected from soils found in the study area. The Brazilian PTFs showed to be un-satisfactory for estimating SWRCs in the study area.The developed regression equations (PTFs) show to be good predictors of volumetric water contents at different matric potentials. The estimation of available water capacity using the PTFs was poor for both the Brazilian PTFs and the PTFs developed using data from the study area. This paper shows that when SWRCs are estimated accurately, crop consumptive water use and yield response can be reasonably estimated. This is useful in assessing the sustainability of soil water management and productivity.