Sammanfattning

Organic inputs [e.g. animal manure (AM) and plant residues] contribute directly to the soil organic N pool, whereas mineral N fertilizer contributes indirectly by increasing the return of the crop residues and by microbial immobilization. To evaluate the residual effect of N treatments established in four long-term (> 35 yr) field experiments, we measured the response of barley (grain yield and N offtake at crop maturity) to six rates (0, 30, 60, 90, 120 and 150 kg N/ha) of mineral fertilizer N (N(new)) applied in subplots replacing the customary long-term plot treatments of fertilizer inputs (N(prev)). Rates of N(prev) above 50-100 kg N/ha had no consistent effect on the soil N content, but this was up to 20% greater than that in unfertilized treatments. Long-term unfertilized plots should not be used as control to test the residual value of N in modern agriculture with large production potentials. Although the effect of mineral N(prev) on grain yield and N offtake could be substituted by N(new) within a range of previous inputs, the value of N(prev) was not eliminated irrespective of N(new) rate. Provided a sufficient supply of plant nutrients other than N, the use-efficiency of N(new) did not change significantly with previous mineral N fertilizer rate. The residual effect of mineral N fertilizer was negligible compared with the residual effect of N from AM and catch crop residues.

Nyckelord

Residual effect; soil nitrogen; N use-efficiency; spring barley; animal manure; catch crops

Publicerad i

Soil Use and Management
2010, Volym: 26, nummer: 4, sidor: 455-464
Utgivare: WILEY-BLACKWELL PUBLISHING, INC

SLU författare

• Mattsson, Lennart

  • Institutionen för skoglig marklära, Sveriges lantbruksuniversitet
    

Globala målen

SDG12 Säkerställa hållbara konsumtions- och produktionsmönster


UKÄ forskningsämne

Jordbruksvetenskap


Publikationens identifierare

DOI: https://doi.org/10.1111/j.1475-2743.2010.00297.x

Permanent länk till denna sida (URI)

https://res.slu.se/id/publ/60463