Elaheh Naeeminia

The role of present NFTs Species in Agroforestry Systems  – A case study in Arvankenar, Abadan

Abstract:

In Arid and semiarid regions trees have noticeable effects on soil resources distribution and its biochemical processes. Organic materials are naturally much more in the understory than out of it. Acacia nilotica and Prosopis juliflora are two nitrogen fixing trees (NFTs) which mainly grew in arid and semiarid tropics and   tropics. In Arid and semiarid regions trees have noticeable effects on soil resources distribution and its biochemical processes. Organic materials are naturally much more in the understory than out of it. Acacia nilotica and Prosopis juliflora are two nitrogen fixing trees which mainly grew in arid and semiarid tropics and tropics. These Nitrogen fixing trees are multipurpose by their ability in producing fodder, timber and fuel and since they are resistant to aridity, they are suitable for rehabilitation of degraded lands in arid and semiarid tropics. This study was done to reveal and compare the effects of Acacia and Prosopis trees on the physical and chemical properties of the soil and their results on the growth of understory plants. The studied trees located in Armandkenar suburb of Abadan County and not expose to any fertilizer. To achieve the goals, the understory soil of Acacia, Prosopis and control (situated in an open area at about one kilometer distance of the trees) at three depths 0-20, 20-40 and 40-60 cm with three replications were analyzed based on completely randomized factorial experiment. The studied parameters include: mineral nitrogen, Dissolved organic nitrogen, nitrogen mineralization potential, total nitrogen, organic carbon percentage, lime, EC, pH, soil texture and criterion plant analysis. These variables show the potential of the trees in nitrogen absorption and production of the criterion plant. Approximately in all the studied parameters the two trees had a significantly different effect on the soil and both respect to the control. This shows the high potential and positive effect of NFTs on soil quality compare to the uncovered areas. In other studies, carbon and other nutrients increase in the understory of these trees during biological rehabilitations projects were reported. Most of mineral nitrogen, Dissolved organic nitrogen, nitrogen mineralization potential, total nitrogen was observed in 0-20 cm depth of soil and they will reduce in deeper soils. In fact litter decomposition plays a great roll in nutrient and physical quality improving of the soil. The effect of Prosopis on nitrogen mineralization potential and finally mineral nitrogen shows the improving effect of this tree on soil microorganisms' condition