Nutrient interactions and salinity effects on plant uptake of phosphorus from waste-based fertilisers

Many organically managed farms in Europe have low levels of soil phosphorus (P). Arable farms that rely strongly on biological nitrogen fixation (BNF) have been shown to have rather low outputs and a tendency to deplete soil P and potassium (K) compared with arable farms that have a lower reliance on BNF and higher external inputs. Therefore, research focusing on providing a balanced input of nitrogen (N), P, K and sulphur (S) from alternative sources is of interest to organically managed farms in Europe.

Livelli di fosforo, potassio e calcio nei prodotti alimentari biologici e convenzionali: una ricerca tedesca

Uno studio tedesco,  BfR MEAL , ha analizzato 356 prodotti alimentari e ha trovato livelli simili di fosforo (P), potassio (K) e calcio (Ca) tra prodotti biologici e non biologici (convenzionali). Differenze significative sono emerse per le olive: Ca più basso, forse dovuto all'additivo cloruro di calcio usato nel sistema convenzionale, K più alto, forse nel sale marino usato per le olive biologiche e P più alto, attribuito dagli autori (sorprendentemente) ad un uso più elevato  di fertilizzanti per le olive biologiche.

Results of the BfR MEAL Study: The food type has a stronger impact on calcium, potassium and phosphorus levels than factors such as seasonality, regionality and type of production

Published in “Food Chemistry”. The BfR MEAL Study aims to provide representative levels of chemical substances in foods consumed by the population in Germany for dietary exposure assessment. Calcium, potassium and phosphorus (Ca, K, P) are essential to obtain physiological functions in humans. Levels were investigated in 356 foods. Foods were purchased representatively, prepared as typically consumed and pooled before analysis.