Abstract
Coastal agroecosystems are usually characterized by saline sandy soils with low fertility and crop productivity. An integrated approach with the inclusion of silviculture with crop cultivation is important to maintaining the soil fertility and crop productivity. Agrisilvicultural System is one of the alternative land use systems by which both woody perennials and agricultural crops are grown simultaneously in degraded lands. Hence an agrisilvicultural study was initiated to determine the effect of tree species on the yield of inter crops at Portnova region of Tamil Nadu. Four woody perennials were established during October 2003 and five field crops were raised in the interspaces of trees during 2003 to 2005 in split plot design. Grain yield of all crop components were affected by trees. Among the woody perennials, the maximum tree growth was observed in Eucalyptus tereticornis. followed by Casuarina equisetifolia Anacardium occidentale and Moringa oleifera. Grain production was found to be the best from the interspaces of Moringa oleifera and Anacardium occidentale. The cause might be due to less light interception of canopies due to wider spacing of trees and able to extract less amount of moisture from the rhizosphere zone of crop components. The lowest yields of field crops were obtained in association with Eucalyptus tereticornis due to more moisture absorption by this tree.
Keywords
Coastal agro-ecosystems, Saline sandy soils, Fertility, Crop productivity, Cultivation, Agrisilvicultural system, Rhizosphere zone