Evaluating Nitrogen Transfer from Caragana Shelterbelt and Its Effects on Yield and Nutrition of Forage Crops

Evaluating Nitrogen Transfer from Caragana Shelterbelt and Its Effects on Yield and Nutrition of Forage Crops

wca2014-1580 Anthony Kimaro 1,*Gazali Issa 2John Kort 3Diane Knight 2 1ICRAF-Tanzania Country Programme, World Agroforestry Centre (ICRAF), Dar-es-Salaam, Tanzania, United Republic of, 2Soil Science, University of Saskatchewan, Saskatoon, 3 Agroforestry Development Center, Agriculture & Agri-Food Canada, Indian Head, Canada

The overuse of synthetic nitrogen (N) fertilizer to meet the requirements of food and forage crops species contributes to environmental problems such as nitrate leaching to groundwater and enhanced greenhouse effects through N2O emissions. Agricultural practices integrating legumes and food or forage crops can address this problem by reducing the reliance on industrial fertilizers through fixation and transfer of N by legumes to associated crops. Belowground N transfers in various systems have been widely researched, however, within the Prairies, there is dearth of information regarding N transfer in shelterbelt-based systems. The field experiment was conducted to determine the amount of N transferred from Caragana shelterbelt to forage crops (triticale and oats) using the 15N natural abundance technique and to assess effects of this transfer on forage biomass and quality. Plants close to the shelterbelt row received significantly higher % N and actual N transferred compared to those further away. The range of the % N transfer spanned from 8-64 % and 16-70 % for the 2011 and 2012 seasons, respectively. This amount was equivalent to the transfer of 33-329 g N m-2 ­and 67-228 g N m-2 in triticale and oats, respectively, and it was within the optimum N application rates for these crops. The belowground N transfer reached the optimum N rates even up to 20 m away from the shelterbelt. Total N and crude protein of the test crops improved significantly with the distance from the shelterbelt, signifying that the amount of N transferred enhanced forage crops nutrition. Biomass yield was, however, not affected suggesting that N may not be the main factor driving crop growth in the study site. This study suggests that the N requirements of the forage species can be met by N from the shelterbelt

Vigyan Bhavan & Kempinski Ambience

10 - 14 February 2014 Delhi, India