The impact of a shelterbelt on soil properties an microbial activity in an adjacent corp field

Studies were carried out in a 8 years old shelterbelt planted across croplands (D. Chłapowski Landscape Park, region of Wielkopolska, western Poland) and in the easterly adjacent field. The effect of the shelterbelt on: soil organic matter content, soil respiration, microbial biomass, dehydrogenase activity, mineralization potential of N and total number of bacteria and fungi in the upper soil layer was analysed. Samples were collected along parallel sites situated in the central part of the strip (S), in the wood edge (Es), field edge (Ef) and in the field 10 m (F10) and 50 m (F50) away from the strip. All studied microbial parameters, except for plate counted total numbers of bacteria and fungi, showed a high and significant correlation with soil respiration and microbial biomass. The highest values were found in the wood soil, lowest in the field soil and intermediate in the field edge. Marked vertical differences between layers 0-3 and 3-10 cm were noticed on sites S, Es and Ef while stratification in the field was visible not earlier than 11 months after ploughing. Some parameters: soil organic matter contents, dehydrogenase activity, microbial biomass estimated by fumigation-extraction method and mineralization potential of N, showed a regular pattern along the gradient from the shelterbelt to the middle of the field. The study suggests a favourable effect of a shelterbelt on organic matter content in the adjacent field. This effect may increase with age of the wood strip.