There are serious debates on the application of prescribed burning in grassland biodiversity conservation in Europe. Some conservationists highly welcome prescribed fire, while others are strongly against it. These contrasting attitudes are likely due to the lack of proper scientific knowledge on both short- and long-term effects of fires on grassland biodiversity in Europe. The international and national media often reports on damages in nature, human life and property caused by catastrophic wildfires and arson, which further increases the negative attitude towards even controlled and carefully designed prescribed fires.
To provide a quantitative analysis of fire effects on grassland species, prescribed burning studies offer the most proper source of information. Our recent review evaluated the results of European attempts to use prescribed burning in grassland management and assessed whether or not the targeted objectives were achieved. Prescribed burning studies from North-America were selected as a reference system to identify which elements of fine-tuned fire management can be adapted to the European grassland conservation strategy.
The effects of fire on European grasslands are rarely documented; there were only 11 publications available about prescribed fires in European grasslands. Most studies applied dormant-season burning on an annual basis and concluded that annual burning solely is not feasible for maintaining the targeted structure and composition of grasslands. Obviously, too frequent burning did not allow the vegetation to recover between burns.
In North-America prescribed burning is widely and successfully used for nature conservation purposes in grasslands. Thus, there is a need for focused case studies to test whether the well-developed North-American burning regimes can be adapted to the European grassland conservation strategy. The review paper indicates the most promising management objectives of prescribed burning experiments in European grasslands.
Both European and North-American studies found that dormant-season burning can effectively reduce accumulated biomass and litter but has only minor effects on the flora and fauna. Prescribed burning could be tested on sites where management by grazing or mowing is not feasible, like in grasslands located far from farms or settlements.
Some studies mentioned positive effects of burning on several rare or protected species by creating suitable germination microsites or warmer and drier microclimate. Focused case studies on certain target species could be integrated in future conservation actions. However, burning is not recommended on sites, where remnant populations of endangered species are present.
Based on North-American studies, patch-burning management (combination of fire and grazing) increases structural and functional diversity. In extended grassland areas, prescribed burning can also be a proper tool for preventing huge and uncontrolled wildfires and contributes to the protection of personal safety and private property. In extended open landscapes, like Central- and Eastern European steppes introduction of patch-burning management would also increase landscape-level heterogeneity.
Despite the serious conservation problems caused by invasive species, fire against them has not been studied yet in Europe. In North-America, carefully designed prescribed burning is effectively used against several invasive species. Based on these studies, timing should be fine-tuned to the most susceptible period of the given invasive species. Invasion control by prescribed burning should be first tested in highly infested areas without outstanding nature conservation values to avoid damaging populations of rare species.
Based on our review, prescribed burning of grasslands might hold a great potential for the European nature conservation practice. However, further habitat-specific prescribed burning experiments are essential to find specific application circumstances and management objectives.
For more detailed information read our open access paper entitled ‘Review: Prospects and limitations of prescribed burning as a management tool in European grasslands’ published in Basic and Applied Ecology which you can freely download (Open Access) here We hope that our review stimulates discussion and generates further research activity about prescribed burning.
Orsolya VALKÓ, Péter TÖRÖK, Balázs DEÁK, Béla TÓTHMÉRÉSZ
MTA-DE Biodiversity and Ecosystem Services Research Group