The sustainability of growing agricultural energy crops in a changing climate perspective

Abstract

The climate change simulation for winter wheat productivity shows, that increasing air temperature could shorten winter wheat vegetation duration, and the productivity decrease also and this effect higher will be under conventional management grown crops. For this reason, new crop varieties with longer vegetation periods for stable productivity of crops are needed. The bioenergy share in total energy consumption plays important role in most countries, especially Northern European ones. Most Northern European countries have historical traditions in the use of forests and much research is done in this area, but nowadays greater attention is being paid to the agricultural sector and the use of agriculture-derived biomass for the generation of bioenergy. Some years ago Baltic countries and other northern climate countries were a black spot in the world for cultivation of miscanthus or other high-yielding crops, but in past few years it was noticed that for example in Lithuania it is possible to grow this crop and harvest even more than 15 t ha-1 of dry matter annually. But not only herbaceous crops are becoming much more interested - the maize or wheat cultivation for bioenergy purposes is also very important. The aim of this study was to evaluate the biomass potential, its quality and energy balance of the cultivation of the most important agricultural crops – maize, spring and winter wheats grown in different management intensity simulate their growing intensity productivity in changing climate perspective. In the present research agricultural crops were fertilised with biogas digestate – as potential organic fertiliser. The field experiments were carried out in 2017. Digestate made from pig as well as from chicken manure in mixture with crop biomass was used for the crop fertilisation; the results were compared to those fertilised with mineral fertilisers. The results of the experiment suggest that the biogas digestate could be a useful fertiliser for crops. The simulations of computer model DSSAT suggest, that increasing September air temperatures, as provided by climate changes projections will become more favorable for productivity of maize, however the risk of early autumn frost remains.