Abstract
Agroforestry is viable option to alleviate the land degradation and loss of soil fertility from the agricultural fields. In Gojer Watershed Gubalafto District of Amhara region, Acacia seyal trees are deliberately left and managed, which naturally grow inside farmlands to fulfill wood requirements and generate extra income.
Since, the effects of this tree on crop productivity and carbon stock have not been scientifically quantified; this study has been carried out with the aim of investigating teff yield, assessing soil nutrients and carbon stock of Acacia seyal based agroforestry system. Three transect lines were established along the gradient with 300 meters apart and 40m×50m is the area of string plot were systematically laid at the interval of 200 meters apart for the inventory of Acacia seyal. Total forty eight composite soil sample were collected at six tree base from (2, 2-4, 4-6 and 12) meters and two soil depths (0-20 and 20-40 cm) were taken for analysis of soil fertility parameters. Grain yields was collected (1 m × 1 m sub plot) just adjacent to soil sample plot following the same procedures as soil sampling. The results shown that, Acacia seyal farmland contribute 20.848±7.115 Mg carbon ha-1. Soil organic carbon, soil pH, available phosphorous and potassium were not influenced significantly at (p>0.05) under Acacia seyal canopy than open field. Whereas total nitrogen, available and Teff yield were significantly (P<0.05) influenced. This could be due to, root uptake of nutrient from deeper soil profiles, modification of microclimate and soil temperature under tree canopy than open field. As a result, Adoption of Acacia seyal parkland agroforestry practices can be potential activity in yield improvement and climate change mitigation.
Keywords: adaptation, crop productivity, open field, soil nutrient, under canopy.
