Effects of management practices on ecosystem processes in European beech forests

Abstract

Nutrient cycling in forest gaps has received little attention until now, although gap regeneration is important for natural dynamics and forest management practices in temperate forests. Gaps of 30 m diameter were cut in a mature European beech forest (Fagus sylvatica L.) in the Soiling Hills in Northwest Germany. The forest has been destablished through prolonged atmospheric pollutants. Deposition, plant uptake, nitrogen mineralization, seepage water chemistry and element losses were compared between limed and untreated gaps and the mature beech stand. The most obvious changes in the element cycle in gaps occurred in the output fluxes of nitrate, cations, heavy metals and laughing gas. The seepage water concentrations of nitrate and cadmium in the unlimed gaps exceeded drinking water thresholds. The major difference in seepage water concentrations of nutrients between gaps was caused by the development of the herbaceous vegetation in the limed gaps. Gap creation did not increase N mineralization as repeatedly reported for large-scale clear cuts.