Permalink : http://hdl.handle.net/2115/84984

JaLCDOI : 10.14943/lowtemsci.80.309

KEYWORDS : 大型水生植物;尾瀬ヶ原湿原;環境変化;池溏;aquatic vascular plants;bog pools;environmental change;Ozegahara mire

本州最大の泥炭地・山岳湿原である尾瀬ヶ原における池溏1,639箇所で詳細に地形と大型水生植物の有無の把握を2017～2019年に行った. 現地調査の結果，1998年の池溏リストと比べて池溏が80箇所（4.9%）消失し，浅い池溏において渇水のため水が減って乾いたことが主な要因と考えられた．前回1998年の調査と比較して大型水生植物の割合は，上田代ではヒツジグサは増加，オゼコウホネは減少し，中田代ではヒツジグサは増加し，オゼコウホネはやや増加した．上田代はヒツジグサ，背中アブリ田代はミツガシワとオゼコウホネ，西中田代と中田代や泉水田代はヒツジグサとミツガシワが特徴的に多く分布していた．田代によってヒツジグサとオゼコウホネは増減が異なりその原因の一つは気候変動による洪水の多少が関係していると考えられた．
Ozegahara mire is the largest peatland (7.6 km2) and located on the amphitheater-shaped basin surrounded by high mountains of 2,000 m in Japan. We conclude that vegetation surveys using UAV are possible and are capable of a highly precise community division in places where field reconnaissance is difficult. The eighty (4.9%) of 1,639 of the bog pools in Ozegahara mire from 2017-2019 were disappear compared with the pool list of surveys in 1998. The reason of degreased phenomenon was expected because of the drought at dry year and the shallow depth of bog pools. Nymphaea tetragona was increased at Kamitashiro area, Nuphar pumila var. ozeensis was decreased at Kamitashiro area compared with the vegetation in 1998. Nymphaea tetragona was small increased at Nakatashiro area, Nuphar pumila var. ozeensis was increased at Nakatashiro area at the same time. Kamitashiro area was characteristic of dominant species of Nymphaea tetragona. Senakaaburitashiro area was characteristic of dominant species of Menyanthes trifoliata and Nuphar pumila var. ozeensis. Nishinakatashiro, Nakatashiro and Sensuitashiro area was characteristic of dominant species of Menyanthes trifoliata and Nymphaea tetragona.