Effects of Prosopis juliflora (DC.) Tree on Under Canopy Resources, Diversity, and Productivity of Herbaceous Vegetation in Indian Desert

Effects of Prosopis juliflora (P. juliflora) (Swartz) DC on vegetation composition and productivity were investigated for an effective management and restoration of Indian desert pasturelands. The strategies of canopy removal and trenching around trees were used to reduce competition between the tree and herbaceous vegetation. Treatments were: intact tree without trench (TC+TR-), intact tree and trench (TC+TR+), lopped tree without trench (TC-TR-), lopped tree and trench (TC-TR+), and a control without tree. Photosynthetically active radiation decreased by greater than 85% under the canopy of P. juliflora. Out of 20 herbage species, 17 were under P. juliflora. Species diversity, population size, herbage dry biomass, soil organic matter, and nutrients concentrations were highest in treatments with intact tree and trench. Soil water content was 17% less under the intact tree than in the lopped tree. P. juliflora utilized deeper soil water during drought in 2002. The highest dry mass was in September 2003 and it decreased by >35% starting December onward. Drought induced mineralization and increased soil nutrients and enhanced dry mass in 2003 over that in 2001. Peristrophe paniculata contributed 64% of the total biomass. Conclusively, canopy retention of P. juliflora trees and trenching around the trees improved soil resources, diversity, and herbage production, which may be beneficial for sustained productivity of rangelands.