Four irrigation and fertilization treatments used in production of lettuce in groundwater protection area (Ljubljansko polje) were applied and tested for their potential for nitrate leaching. 15N labelled fertilizer was used to trace the movement of N. Environmentally sustainable practices (split vs. broadcast fertilisation) were tested. Fertigation and improved irrigation scheduling efficiently minimized nitrate leaching, and should be considered for vegetable production in or close to groundwater protection zones.
COBISS.SI-ID: 6820217
We report preliminary data on δ15N values in organically and conventionally grown vegetables available on the Slovenian market to determine whether δ15N values could be used as a marker to differentiate between organically and conventionally grown vegetables. 14 different varieties of organically and conventionally grown vegetables were analysed. It was not possible to differentiate between organically and conventionally grown counterparts in eight vegetable varieties. Hence, δ15N cannot be used as the only indicator for organic production, but needs to be validated by background information.
COBISS.SI-ID: 24590887
The δ15N value in lettuce was tested as a potential marker for identifying the use of synthetic fertiliser on pot-grown lettuce treated with different combinations of synthetic and organic fertilisers in single and split applications. The δ15N values differed significantly in the case of single treatment. The δ15N value could only be used as a rough marker to reveal the history of fertilisation only in the case of single application. The detection of split and combined fertilization could only be detected if the difference in δ15N between synthetic and organic nitrogen fertilisers was )9.1‰.
COBISS.SI-ID: 23930151