English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

Fractionation by particle size provides a rough differentiation between young active, and older intermediate and passive soil organic matter. Soil samples from three treatments of a 20 years` fertilization experiment, C2 which had been fertilized with 10 t ha -1 (wet wt.) compost per year on average, N2 with mineral N fertilizer at 32 kg N ha -1 year -1 , and the unfertilized control (O) were subjected to particle size fractionation and to density fractionation. After low-energy sonication the samples were separated into the size fractions coarse sand (200-200 µm), fine sand (200-63 µm) silt (63-2 µm) and clay (2-0,1 µm). Density fractionation using Na-polytungstate with 1.8 g cm -3 density was applied to separate particulate organic matter (POM) from the sand-sized fraction. Compost fertilization resulted in an increase in C org in all size and density fractions. In total, the C org content was 10 % higher with compost fertilization than in the unfertilized control. Approximately 40 % of the additional soil carbon was located in the POM, 56 % in the silt-sized fraction and 3 % in the clay-sized fraction. With mineral N fertilization the sum of C org contents of all fractions was about the same as without fertilization, with an increase of POM-C org and a decrease of C org in the silt and clay-sized fraction. Keywords: fractionation, particulate organic matter, POM, soil organic matter

Carbon storage in soil size-density fractions after 20 years of compost fertilization