Initial changes in soil properties and carbon sequestration potential under monocultures and short-rotation alley coppices with poplar and willow after three years of plantation

Azeem Tariq; Anna Gunina; Norbert Lamersdorf

doi:10.1016/j.scitotenv.2018.03.391

Initial changes in soil properties and carbon sequestration potential under monocultures and short-rotation alley coppices with poplar and willow after three years of plantation

Sci Total Environ. 2018 Sep 1:634:963-973. doi: 10.1016/j.scitotenv.2018.03.391. Epub 2018 Apr 11.

Authors

Azeem Tariq¹, Anna Gunina², Norbert Lamersdorf³

Affiliations

¹ Department of Plant and Environmental Sciences, University of Copenhagen, Thorvaldsensvej 40, DK-1871 Frederiksberg C, Denmark; Büsgen-Institute, Soil Science of Temperate Ecosystems, Georg August University of Göttingen, Büsgenweg 2, 37077 Göttingen, Germany. Electronic address: azeem@plen.ku.dk.
² Department of Agricultural Soil Science, Georg August University of Göttingen, Büsgenweg 2, 37077 Göttingen, Germany.
³ Büsgen-Institute, Soil Science of Temperate Ecosystems, Georg August University of Göttingen, Büsgenweg 2, 37077 Göttingen, Germany.

PMID: 29660890
DOI: 10.1016/j.scitotenv.2018.03.391

Abstract

Initial changes in soil structure and C stocks were studied under short-rotation coppices (SRC) planted on former cropland near Göttingen, Central Germany. Plantations were established either as monocultures with willow (Willow-SRC) or poplar (Poplar-SRC), or as an agroforestry system with willow strips and grassland alleys in between (Willow-AF). A neighbouring cropland served as a control. Three sampling campaigns were applied in this study. The first sampling was conducted at a fine scale to reveal the differences in soil C with depth (i.e. 0-3, 3-6, 6-9, 9-12, 12-15, 15-20, 20-30cm). Here, results indicated the main differences between plantations in 0-3, 3-20 and 20-30cm layers. These soil depths were therefore chosen for the second sampling campaign to reveal differences in aggregate composition, C accumulation in aggregates and density fraction, and microbial biomass carbon (MBC) between plantations. Furthermore, quality of soil organic matter and amount of C mineralised by microorganisms were estimated by an incubation experiment. Results here indicated two times higher CO₂ emissions from the top layer than from the lower layers under SRCs, as well as higher MBC in SRCs (490-788.7μgCg^-1) than in cropland (266.4μgCg^-1). The results of the third sampling on the texture of respective soil horizons indicated a significant correlation (R²=78%) of soil clay to C at 0-3cm depth. It was concluded that aggregation and C in microbial biomass and free light fractions were the first indicators of soil quality improvement after conversion of arable land to SRC plantations.

Keywords: Aggregate stability; Carbon sequestration; Land use change; Microbial biomass; Particulate organic matter; Short-rotation coppice.