平成 30 年度

環境科学院

修士論文内容の要旨

Detecting the effectiveness of Sphagnum transplantation for restoring wetland
ecosystem after peat mining in Sarobetsu Mire, northern Japan(サロベツ湿原泥炭採掘跡地における湿原生態系復元を目的としたミズゴケ移植有効性の検証)

Hokkaido University, Graduate School of Environmental Science
Division of Environmental Science Development, Course in Human and Ecological Systems
Jia Yumeng
The re-establishment of Sphagnum mosses on the post-mined peat surface is a priority for therestoration of bogs. Transplantation of Sphagnum sometimes promotes vegetation recovery. Theeffects of transplantation differ between post-mined peatlands worldwide. In addition,transplantation is often conducted with pre-and post-treatments, such as litter mulch to increase
the success of establishment. The present study was conducted in Sarobetsu mire, a post-mined
peatland in northern Japan, to clarify the possibilities of restoration through moss transplantation.
The successional sere after the peat mining is bare ground (BG) - Rhynchospora alba sedgeland(RA) - Moliniopsis japonica grassland (MJ) - peat moss carpet dominated by Sphagnum
papillosum (ST). The transplantation of S. papillosum was conducted to these four habitats withand without litter mulch, consisting of R. alba or M. japonica.
The transplantation was conducted before snow accumulation in October 2017 and soon aftersnow-melting in April 2018 to detect the suitable transplantation timing. Litter mulch wasperformed to 1/2 of plots. In total, 320 plots were established based on the block design: 4(vegetation) × 2 (timing) × 4 (mulch) × 10 (replication). Until late fall in 2018, the growth ofSphagnum was monitored by four parameters related to biomass or productivity, i.e., verticalgrowth, NDVI (normalized difference vegetation index), capitulum density and Sphagnum cover.
The biomass was measured by harvesting during the final survey. Vegetation survey wasconducted in September 2017 and July 2018. Water table, pH, light intensity and temperature werealso monitored in 2018 to inspect the relationships between Sphagnum growth and environments.
Sphagnum showed higher vertical growth, biomass productivity and capitulum density in ST,
higher vertical and horizontal growth with low capitulum density in MJ and high capitulum
density in RA. Sphagnum were lost mostly from BG. The litter mulch promoted the vertical
growth but did not change the biomass of moss, suggesting that shade induced spindly growth.
Sphagnum tended to establish on the habitats showing high species richness of vascular plants,high pH, moderate light intensity and moderate temperature, as seen in MJ. Generalized linear
regression showed that the biomass was predicted well by the four examined parameters. The
biomass growth in un-harvested plots was estimated by the regression.
Even though the transplanted Sphagnum increased the cover, the total biomass growth wasslower than in-situ Sphagnum (used as control) during the first year of transplantation. These
results suggested that damages induced by the transplantation remained for one year or more.
However, the transplanted moss survived mostly on the plots in MJ and RA and grew well on a
few plots there. This study developed a precise and non-destructive method to estimate moss
biomass and found out the techniques of moss transplantation to accelerate the succession.

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