Details

Autor(en) / Beteiligte

• Tresch, Simon
• Frey, David
• Le Bayon, Renée-Claire
• Zanetta, Andrea
• Rasche, Frank
• Fliessbach, Andreas
• Moretti, Marco

Titel

Litter decomposition driven by soil fauna, plant diversity and soil management in urban gardens

Ist Teil von

• The Science of the total environment, 2019-03, Vol.658, p.1614-1629

Ort / Verlag

Netherlands: Elsevier B.V

Erscheinungsjahr

2019

Link zum Volltext

Quelle

Elsevier ScienceDirect Journals Complete

Beschreibungen/Notizen

• In the face of growing urban densification, green spaces in cities, such as gardens, are increasingly important for biodiversity and ecosystem services. However, the influences of urban green space management on biodiversity and ecosystem functioning (BEF) relationships is poorly understood. We investigated the relationship between soil fauna and litter decomposition in 170 urban garden sites along a gradient of urbanisation intensity in the city of Zurich, CH. We used litter bags of 1 and 4 mm mesh size to evaluate the contribution of soil meso- and macrofauna on litter decomposition. By using multilevel structural equation models (SEM), we investigated direct and indirect environmental effects and management practices on litter decomposition and litter residue quality. We evaluated the role of taxonomic, functional and phylogenetic diversity of soil fauna species on litter decomposition, based on a sample of 120 species (81,007 individuals; 39 collembola, 18 earthworm, 16 isopod, 47 gastropod species). We found highest litter decomposition rates using 4 mm mesh size litter bags, highlighting the importance of soil macrofauna. Urban warming, a proxy for urbanisation intensity, covaried positively, whereas soil disturbances, such as intensive soil and crop management, were negatively correlated with decomposition rates. Interestingly, soil fauna species richness decreased, with the exception of gastropods, and soil fauna abundance increased with urban warming. Our data also show that plant species richness positively affected litter decomposition by increasing soil fauna species richness and microbial activity. A multivariate analysis of organic compounds in litter residues confirmed the importance of soil fauna species richness and garden management on litter decomposition processes. Overall, we showed, that also in intensively managed urban green spaces, such as gardens, biodiversity of plants and soil fauna drives key ecosystem processes. Urban planning strategies that integrate soil protecting management practices may help to maintain important ecosystem services in this heavily used urban environment. A priori conceptual structural equation model depicting direct pathways of soil fauna as well as direct and indirect pathways of soil characteristics, land-use features, garden management, garden features and urbanisation intensity on litter decomposition. [Display omitted] •Garden management affected both fauna diversity and litter decomposition•Garden land-use types had the biggest effect on litter decomposition•Soil fauna species richness covaried positively with decomposition rates•Plant diversity increased fauna diversity and microbial activity•Urbanisation density was positively associated with litter decomposition•MidDRIFTS analysis revealed variance in litter residue quality after decomposition