Soil water content and photosynthetic capacity of spring wheat as affected by soil application of nitrogen-enriched biochar in a semiarid environment

A field trial was conducted to determine the effect of nitrogen-enriched biochar on soil water content, plant's photosynthetic parameters, and grain yield of spring wheat at the Dingxi Experimental Station during the 2014 and 2015 cropping seasons. Results showed that biochar applied with nitrogen fertilizer at a rate of 50 kg ha(-1) of N (BN50) increased soil water content in the 0-30 cm depth range by approximately 40, 32, and 53% on average at anthesis, milking, and maturity, respectively, compared with zero-amendment (CN0). Stomatal conductance and net photosynthetic rate after the BN50 treatment increased by approximately 40 to 50% compared to CN0. Soil water content and photosynthetic traits also increased in other treatments using straw plus nitrogen fertilizer, but to lesser extent than that of BN50. Grain yields were highest (1905 and 2133 kg ha(-1) in 2014 and 2015, respectively) under BN50. From this, biochar appears to have a potential for its use with N-fertilizer as a cost-effective amendment for crop production in semiarid environments.