engleski

Invasive Brachypodium rupestre on Ćićarija (Croatia) grasslands: threat to plant diversity or good feed for animals?

During this research (2008-2010) the occurrence of the invasive species Brachypodium rupestre on the Ćićarija grasslands has been recorded. This grass is quite abundant in mowed meadows and grazed pastures (cover up to 25%), with even greater spread in abandoned meadows and pastures (cover more than 25%). This phenomenon could be explained because of the low intensity use of grassland: in hay meadows, competition for light after abandonment and the higher water and soil nitrogen content, allow the invasion of B. rupestre which quickly spreads by means of rhizomes and tends to form extensive patches. Our results indicate that B. rupestre, in comparison with the abandoned meadow, had a greater neutral detergent fibre fraction (NDF, 733.0 vs. 616.5 g/kg DM) and better energy value (NEL, 5.82 vs. 5.35 MJ/kg DM) due to lesser content of acid detergent fibre (ADF, 328 vs. 365 g/kg DM). Spring amount of crude protein was 132 g/kg DM. Indicator species analysis (ISA) detected the B. rupestre as indicator species related to unmowed meadows and dry pastures. The analyses performed in this study indicate that undergrazing and non-periodic mowing make the grasslands quite homogeneous. As a matter of fact, meadows are more subjected to the invasion of B. rupestre and they are more vulnerable than pastures to the loss of floristic diversity because of management abandonment. For this reason, regular mowing should be maintained and incentivized. Because of its clonal growth organs (rhizomes) B. rupestre spreads very quickly after fire. Consequently, the use of controlled burning must be a very limited application. As regards pastures, since the threat of loss of species diversity is lower, a low grazing pressure should be maintained by grazing rotation. B. rupestre is nutritious but less palatable species by qualitatively classification and the grazing with less selective herbivores (cattle, donkeys and horses) could be a successful solution to control this invasive species.

Brachypodium rupestre; grassland; feed; Ćićarija; Croatia

nije evidentirano