Lei Liang  , Ning Hu  , Da Tian Jin  , Lu Lu Zhao  , 
    Evaluating Optimum Nitrogen Management Associated with Production and Environmental Load of Farm-Systems in the Dahuofang Reservoir Region,
    Environmental Research Journal,
    Volume 2,Issue 5,
    2008,
    Pages 265-270,
    ISSN 1994-5396,
    erj.2008.265.270,
    (https://makhillpublications.co/view-article.php?doi=erj.2008.265.270)
    Abstract: N budgets analysis model offers a new set of tools for evaluating the N cycling in Agricultural systems. Cycling Index (CI) is also a useful tool for estimating optimal N flows in farms and Application Index (AI) as a good indicator for characterizing the N flows in farms. Using these parameters, we analyzed all farm-systems to estimate the optimal N Management for safety N pollution in ground water and maximizing N export in the Dahuofang Reservoir region. It was clearly shown the critical N application rate (chemical fertilizer + manure) was 208.4 kg N ha <SUP>1</SUP> y <SUP>1</SUP>. The critical inter-system input (application N, imported food and feed N and natural supplied N) was 422.5 kg N ha <SUP>1</SUP> y <SUP>1</SUP>.
    Keywords: Agricultural systems;N balance;N Cycling index;N management