Effects of Wooden Field Margins on Soil Ecosystem Functions and Crop Productivity in Southern Saxony-Anhalt (Germany)

Agroecosystems in southern Saxony-Anhalt are under increasing ecological stress due to climate change. The widespread absence of field margins exacerbates this challenge; large-scale land consolidation over recent decades, combined with inadequate management, has led to a substantial reduction in these critical landscape features. However, wooden field margins - hedgerows and tree rows with shrub components - are increasingly recognized as important elements for enhancing soil functions and supporting climate-resilient agroecosystems.

This study quantified the effects of structurally distinct wooded field margins on soil properties and crop productivity. Soil indicators included inorganic parameters (pH and bulk density) and organic indicators (soil organic matter content and Tea Bag Index), complemented by agronomic traits (crop yield and plant height).

Field investigations were conducted at two sites in southern Saxony-Anhalt representing four distinct field margin structures, adjacent to conventionally and organically managed fields. At site one, there were two variants of closed hedgerows with individual trees of differing structural characteristics, and at site two, there were two types of tree rows with differentiated shrub components. Each plot comprised a length of 100 m. Soil and crop parameters were assessed along transects extending from the field margin into the adjacent cropland to capture distance-dependent effects (25 m, 50 m and 100 m). Soil indicators were sampled at five points per transect at 20-m intervals. Yield and plant height measurements were recorded at the proximity of the field margin (approximately 1 m) and at transect positions (25 m, 50 m and 100 m) with replicated sampling.

Preliminary results show significant differences in pH and microbial activity, as measured by the Tea Bag Index, between field margins and open field areas. Measurable margin effects extend up to 25 m into the field. Differences between conventional and organic management were comparatively small. Conversely, crop yield and plant height increased within the 25 m zone adjacent to field margin and declined with increasing distance from the margin. Further analysis will incorporate site management practices and field margin vegetation structure in order to elucidate their interactions with agronomic performance parameters.

These findings demonstrate measurable positive spillover effects of wooded field margins for soil ecosystem functions and crop performance. They provide a basis for evidence-based design and spatial planning of climate-resilient agricultural landscapes under variable conditions.