Observations on the rooting patterns of some agroforestry trees in an arid region of north-western India

摘要

The present study deals with root architecture of 6-year-old trees of 9 indigenous and 3 exotic species growing in arid climate of north-western India. Observations, made on excavated root systems (3 tree replicates of each species) showed large variation in horizontal and vertical spread of roots. InMorus alba, Melia azedarachandPopulus deltoides, the roots were confined to 80 cm, while inProsopis cineraria, Acacia niloticaandEucalyptus tereticornis, roots penetrated more deeply to 233 cm. The number of total roots ranged from 103 inAcacia catechuto 1932 inEucalyptus tereticornis, and 62 to 80 of the roots were less than 2 mm in diameter. The primary roots were more horizontal than the secondary roots. The total root biomass varied from 2.2 kg inAcacia catechuto 30.6 kg−1tree inPopulus deltoides, and top 30 cm soil contained 42 to 78 of the total biomass. The implications of the results are discussed in the context of the ecological niche of the species, and its usefulness in agroforestry system