Abstract
Abstract
Background
Nitrogen (N) as a key input for crop production has adverse effects on the environment through emissions of reactive nitrogen. Less than 20% of the fertiliser nitrogen applied to agricultural land is actually consumed by humans in meat. Given this situation, nitrogen budgets have been introduced to quantify potential losses into the environment, to raise awareness in nutrient management, and to enforce and monitor nutrient mitigation measures. The surplus of the N soil surface budget has been used for many years for the assessment of potentially water pollution with nitrate from agriculture.
Results
For the 402 districts in Germany, nitrogen soil surface budgets were calculated for the time series 1995 to 2017. For the first time, biogas production in agriculture and the transfer of manure between districts were included in the budget. Averaged for all districts, the recent N supply to the utilised agricultural area (UAA) totals 227 kg N ha−1 UAA (mean 2015–2017), among them 104 kg N ha−1 UAA mineral fertiliser, 59 kg N ha−1 UAA manure, 33 kg N ha−1 UAA digestate, 14 kg N ha−1 UAA from gross atmospheric deposition, 13 kg N ha−1 UAA biological N fixation, and 1 kg N ha−1 UAA from seed and planting material. The withdrawal with harvested products accounts for 149 kg N ha−1 UAA, resulting in an N soil surface budget surplus of 77 kg N ha−1 UAA. The N surpluses per district (mean 2015–2017) vary considerably between 26 and 162 kg N ha−1 UAA and the nitrogen use efficiency of crop production ranges from 0.53 to 0.79 in the districts. The N surplus in Germany as a whole has remained nearly constant since 1995, but the regional distribution has changed significantly. The N surplus has decreased in the arable farming regions, but increased in the districts with high livestock density. Some of this surplus, however, is relocated to other districts through the transfer of manure.
Conclusions
The 23-year time series forms a reliable basis for further interpretation of N soil surface surplus in Germany. Agri-environmental programmes such as the limitation of the N surplus through the Fertiliser Ordinance and the promotion of biogas production have a clear effect on the N surplus in Germany as a whole and its regional distribution.
Publisher
Springer Science and Business Media LLC
Reference46 articles.
1. Galloway J, Aber JD, Erisman JW et al (2003) The nitrogen cascade. Bioscience 53:341–356
2. Erisman JW, Sutton MA, Galloway J et al (2008) How a century of ammonia synthesis changed the world. Nature Geosci 1:636–639. https://doi.org/10.1038/ngeo325
3. Fowler D, Coyle M, Skiba U et al (2013) The global nitrogen cycle in the twenty-first century. Philos Trans R Soc Lond B Biol Sci 368:20130164. https://doi.org/10.1098/rstb.2013.0164
4. United Nations Environment Programme (2007) Division of Technology, Industry, and Economics (UNEP), The Woods Hole Research Center Reactive nitrogen in the environment. Too much or too little of a good thing, UNEP/Earthprint, Paris, Falmouth
5. Oenema O, Kros H, de Vries W (2003) Approaches and uncertainties in nutrient budgets: implications for nutrient management and environmental policies. Eur J Agron 20:3–16. https://doi.org/10.1016/S1161-0301(03)00067-4
Cited by
22 articles.
订阅此论文施引文献
订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献