Benefits of conservation-driven mowing for the EU policy species Gladiolus palustris Gaudin in mountain fen meadows:a case-study in the European Alps

The sword lily Gladiolus palustris Gaudin is protected on European level and listed in Annexes II and IV of the EC Habitat Directive 92/43/EEC.It grows in nutrient-poor,calcareous meadows in central and eastern Europe.Tree encroachment in montane meadows of the European Alps as a result of recent land use changes and the abandonment of traditional farming practices threaten the survival of this species.Conservation-driven mowing is considered a feasible conservation measure for maintaining high species diversity in abandoned semi-natural grasslands.To assess the effects of tenyears of biennial mowing on a grassland community in the Dolomiti Bellunesi National Park,Italy(Site of Community Importance,Natura 2000 network),ten25 m2 plots were established whereby four plots were placed in the mowed area,four in the non-mowed area and two in a small non-mowed patch of grassland inside the mowed area.In each plot the following variables were recorded,total percentage of plant cover,percentage cover of woody species,percentage cover of herbaceous species,percentage cover and number of flowering ramets of G.palustris and a complete list of species and their percentage abundance.Mowed plots showed a higher species richness than non-mowed plots.The number of G.palustris flowering ramets and percentage cover increased manifold in mowed plots compared to nonmowed plots.The resumption of mowing forconservation purposes undertaken by the managing authority halted the process of tree encroachment and avoided a drastic change in plant composition.Periodic mowing(every second or third year)was demonstrated to be a cost-effective conservation measure in non-productive grasslands to keep grasses at bay in favour of forbs of high conversation value.

Soil organic carbon stocks and belowground biomass in patches in heterogeneous grassland

Background:Selective grazing creates stable patches of contrasting sward height,thereby providing different growth conditions for the grass sward above and below ground and potentially affecting soil organic carbon(SOC)stocks.We hypothesized that the presence of patches leads to greater spatial variability in belowground biomass(BGB)and SOC stocks than occurs between pastures managed under different stocking intensities.Methods:A long-term grazing experiment consisting of three stocking intensities was used for this study.We studied BGB,SOC,and soil total nitrogen(Ntot)stocks in the 0-15 cm soil depth.Shannon diversity of plant species,soil bulk density,soil phosphorus,potassium,and magnesium contents were considered.Results:There were no significant effects of patch or stocking intensity on BGB,SOC,and Ntot stocks.Short patches had a greater Shannon diversity than tall patches(p<0.05)and plant-available nutrients in soil correlated positively with sward height(p<0.05).Conclusions:We conclude from the current results and previous studies that higher plant species diversity with lower soil nutrient contents in short-patch areas and higher nutrient contents together with light competition in tall-patch areas might balance each other out with respect to BGB and SOC stocks.