Beschreibung:
<jats:title>ABSTRACT</jats:title>
<jats:p>
The wood protection industry has refined their products from chrome-, copper-, and arsenate-based wood preservatives toward solely copper-based preservatives in combination with organic biocides. One of these is Cu-HDO, containing the chelation product of copper and
<jats:italic>N</jats:italic>
-cyclohexyldiazenium dioxide (HDO). In this study, the fate of isotope-labeled (
<jats:sup>13</jats:sup>
C) and nonlabeled (
<jats:sup>12</jats:sup>
C) Cu-HDO incorporated in wood sawdust mixed with soil was investigated. HDO concentration was monitored by high-pressure liquid chromatography. The total carbon and the δ
<jats:sup>13</jats:sup>
C content of respired CO
<jats:sub>2</jats:sub>
, as well as of the soil-wood-sawdust mixture, were determined with an elemental analyzer-isotopic ratio mass spectrometer. The concentration of HDO decreased significantly after 105 days of incubation, and after 24 days the
<jats:sup>13</jats:sup>
CO
<jats:sub>2</jats:sub>
concentration respired from soil increased steadily to a maximum after 64 days of incubation. Phospholipid fatty acid-stable isotope probing (PFA-SIP) analysis revealed that the dominant PFAs C
<jats:sub>19:0</jats:sub>
d8,9, C
<jats:sub>18:0</jats:sub>
, C
<jats:sub>18:1</jats:sub>
ω7, C
<jats:sub>18:2</jats:sub>
ω6,9, C
<jats:sub>17:1</jats:sub>
d7,8, C
<jats:sub>16:0</jats:sub>
, and C
<jats:sub>16:1</jats:sub>
ω7 were highly enriched in their δ
<jats:sup>13</jats:sup>
C content. Moreover, RNA-SIP identified members of the phylum
<jats:italic>Acidobacteria</jats:italic>
and the genera
<jats:italic>Phenylobacterium</jats:italic>
and
<jats:italic>Comamonas</jats:italic>
that were assimilating carbon from HDO exclusively. Cu-HDO as part of a wood preservative effectively decreased fungal wood decay and overall microbial respiration from soil. In turn, a defined bacterial community was stimulated that was able to metabolize HDO completely.
</jats:p>