Increasing crop productivity using a porousα amendment in sandy soil

Author: B. A. Ould Ahmed ^* and M. Inoue

Received 16 January 2009, accepted 28 March 2009.

Abstract

The objective of this study was to determine the effects of a porousα amendment (recycled from used glass bottles) on water holding capacity, crop growth and nutrient availability in a sandy soil assessed by growing Swiss chard (Beta vulgaris L.). Treatments consisted of two porousα layers of 2 and 5 cm thickness placed in the soil. The control soil received no treatment. The experiment was conducted and replicated five times in a sandy field under a greenhouse. A leaching experiment was conducted in a laboratory. The results show the placement of a porousα material substantially increased the yield as compared to the yield of the control soil. The yields were recorded as 12.09, 11.05 and 4.15 Mg ha^-1 for the 2 cm, 5 cm and control treatments respectively. Soil moisture was maintained at more than field capacity under the porousα treatment (i.e. 0.08 to 0.09 cm³ cm^-3), whereas under the control it was < 0.04 cm³ cm^-3. Extracted soil solution analysis detected greater levels of ammonium and potassium in porousα layered soil as compared to those of the control. However, nitrate content was observed to be higher under the control (1.56 mg L^-1) than under the porousα at 2 cm (0.96 mg L^-1) and 5 cm layer (0.80 mg L^-1) treatments. Comparing both porousα layers, the 2 cm thickness proved to be more efficient in terms of crop productivity. This experiment demonstrated that porousα material can be used in the cultivation of sandy soils practically in dryland. Not only does it save water but it also improves nutrient management and improves crop production.

Key words: Dryland, porousα amendment, sustainability, water saving.