open access

https://doi.org/10.14943/lowtemsci.80.269

https://hdl.handle.net/2115/84987

Physico-chemical factors of peat soils in determining mire vegetation in Ozegahara mire, Japan

日本語

peat

2022-03-31

低温科学第80巻編集委員会

Low Temperature Science

80

269-284

The importance of pore water chemistry in the distribution of the mire vegetation was examined by chemical analysis of the peat interstitial water and peat soils of Ozegahara mire, Japan. Along a transect from a riverside to the center of the mire, dominant vegetation changed in an almost decreasing order of plant height from gallery forest, skunk cabbage, reed, sasa-bamboo, Moliniopsis japonica to Sphagnum mat, with sporadic appearance of cinnamon fern (Osmunda cinnamomea) with heights of around 100 cm on the transect way. These vegetations was found to have discrete (Ca2+ + Mg2+) concentration in peat interstitial waters and ash content of the peat soil，indicating a close association of the vegetation types with physico-chemical environment of the peat soils. Most of the survey sites along the transect were identified to be ombrotrophic, judging from the groundwater tables which were much higher than the river surface (up to 6.0 m). Nevertheless, elevated ash contents as high as more than 50% were detected in peat soil especially at the sites of cinnamon fern at deeper layers (15-20 cm and 20-25 cm), suggesting that soil particles had been transported onto the mire through river overflows. SiO2, Ca2+, Mg2+, and K+ concentrations in peat interstitial waters were significantly correlated with fine sand contents in the peat soils at 5-10 cm depth (p<0.05). Height of plants that grow in the ombrotrophic sites showed significant positive correlations with both K+ and Ca2+ concentrations (p<0.05). The survey results suggest that, in Ozegahara mire where is mostly ombrotrophic, soil particles derived from flooding serve as an important mineral source affecting the distribution of vegetation type on the mire.

紀要論文

Version of Record

1880-7593