An assessment of the effect of human faeces and urine on maize production and water productivity

The key challenge facing many catchment authorities in Zimbabwe and elsewhere is the challenge of feeding the growing populations within their catchment boundaries. Modern agricultural practices continue to mine valuable crop nutrients through increased food production to satisfy ever-increasing food demand. In recent diagnostic survey of smallholder agricultural sector in the Manyame catchments of Zimbabwe it was revealed that exhausted soils depleted of their natural mineral and organic constituents by many years of cropping with little fertilization or manuring were the major factors contributing to low yields and poor food security in this sector in Zimbabwe. The objective of the study was to assess the effect of using sanitized human excreta on maize production and water productivity. The study involved six volunteer farmers with four 10 in x 10 in trial plots each with the following treatments the control, commercial fertilizer treatment urine only plot, and the feacal matter and urine plot. Harvest determination was carried by weighing the yield from each of the treatment plots and comparisons done. Water productivity was computed by calculating the amount of water used to produce a tone of maize per ha. The study showed that human excreta improves maize crop production and water productivity in rain-fed agriculture. The study recommends that the ecological sanitation concept and the reuse of human excreta both humanure and (ecofert) urine can be considered as alternative excreta management options in catchment areas. (c) 2005 Elsevier Ltd. All rights reserved.