9月のビオトープ活動では、いつもの調査と併せて陸域部の草刈りを行いました。観察対象の植物に注意を払いながら作業を行い、眺めの良いビオトープ景観を回復させました。(O)
D池一面にミズオオバコの花が咲いていました。まさに「らんまん(爛漫)」です。花は大小合わせて約120個。C池4個、F池12個、合計 約136個咲いていました。観察史上最大です。(図1) 花の大きさは水深によって変わります。(表1)
イボクサ(ツユクサ科、在来種)がA区、D区、F区で増えていた。アカバナ(在来種)が減っていた。A区で3~4株だけ開花を確認した。ツリガネニンジン(在来種)はたくさん咲いていたが、8月の雨不足で枯れている花が多かった。ヒシ、ヒメガマ、カンガレイ、ヤブツルアズキなどが増えすぎている。適正な生態系を保持するためにも半分くらいに駆除の必要がある。(T)
![ミズオオバコ](https://image.jimcdn.com/app/cms/image/transf/none/path/se584097edd0197d0/image/i5f88bed7fc21db7b/version/1695041242/image.jpg)
![ツリガネニンジン](https://image.jimcdn.com/app/cms/image/transf/none/path/se584097edd0197d0/image/i050559d726ec4862/version/1695041273/image.jpg)
![アキノノゲシ](https://image.jimcdn.com/app/cms/image/transf/dimension=159x10000:format=jpg/path/se584097edd0197d0/image/if06d8bb7f8e871eb/version/1695041286/image.jpg)
![ヒヨドリバナ](https://image.jimcdn.com/app/cms/image/transf/none/path/se584097edd0197d0/image/i1b7ddd94b788ad8d/version/1695041301/image.jpg)
![ヤブツルアズキ](https://image.jimcdn.com/app/cms/image/transf/none/path/se584097edd0197d0/image/ib80ff714082d6714/version/1695041322/image.jpg)
![イボクサ](https://image.jimcdn.com/app/cms/image/transf/none/path/se584097edd0197d0/image/i3e28fd7e8212e6a7/version/1695041335/image.jpg)
![コケオトギリ](https://image.jimcdn.com/app/cms/image/transf/dimension=159x10000:format=jpg/path/se584097edd0197d0/image/id05b44bc4c537591/version/1695041356/image.jpg)
![アカバナ](https://image.jimcdn.com/app/cms/image/transf/none/path/se584097edd0197d0/image/ie65eca511df38b40/version/1695041373/image.jpg)
![タカサブロウ](https://image.jimcdn.com/app/cms/image/transf/dimension=159x10000:format=jpg/path/se584097edd0197d0/image/i105fd6b3ac31a97b/version/1695041398/image.jpg)
![オトギリソウ](https://image.jimcdn.com/app/cms/image/transf/none/path/se584097edd0197d0/image/i814fab094ac08def/version/1695041414/image.jpg)
![ネコハギ](https://image.jimcdn.com/app/cms/image/transf/none/path/se584097edd0197d0/image/id59cfd74290bfd62/version/1695041486/image.jpg)
![コマツナギ](https://image.jimcdn.com/app/cms/image/transf/none/path/se584097edd0197d0/image/i41eebb0185f8fdca/version/1695041512/image.jpg)
![サワヒヨドリ](https://image.jimcdn.com/app/cms/image/transf/none/path/se584097edd0197d0/image/i2d3eb3cdc90db9ef/version/1695041527/image.jpg)
![ハシカグサ](https://image.jimcdn.com/app/cms/image/transf/none/path/se584097edd0197d0/image/i30ed7939a47e1a2f/version/1695041543/image.jpg)
![ゲンノショウコ](https://image.jimcdn.com/app/cms/image/transf/dimension=159x10000:format=jpg/path/se584097edd0197d0/image/i6ab7b78d2e903fea/version/1695041559/image.jpg)
![ボントクタデ](https://image.jimcdn.com/app/cms/image/transf/none/path/se584097edd0197d0/image/ib5def74a69ca3492/version/1695041576/image.jpg)
![](https://image.jimcdn.com/app/cms/image/transf/dimension=225x10000:format=png/path/se584097edd0197d0/image/i38dbd055503c09c0/version/1695040965/image.png)
![](https://image.jimcdn.com/app/cms/image/transf/dimension=480x10000:format=jpg/path/se584097edd0197d0/image/i1fbd3fb2f6f8531b/version/1695041023/image.jpg)
(図1) ミズオオバコ