| 要旨トップ | 目次 | 日本生態学会第60回全国大会 (2013年3月,静岡) 講演要旨
ESJ60 Abstract


一般講演(ポスター発表) P2-408 (Poster presentation)

Change of a growth situation of Viola raddeana for 5 years in Sugao-Numa, Ibaraki Prefecture

*澤田みつ子(筑波大・院・生命環境),小幡和夫(茨城県自然博物館),上條隆志(筑波大・生命環境系),中村徹(筑波大・生命環境系)

Viola raddeana is a perennial wetland species listed as endangered species (Category II: vulnerable) in the Japanese Red List. We examined yearly changes of its density at the grassland maintained by prescribed burning. We also conducted a study site of 5 year interruption of burning. Interruption of the prescribed burning resulted in rapid reductions in the density of V. raddeana, especially that of seedlings. However, the density of V. raddeana decreased under annual prescribed burning. Furthermore, increase in the rate of large sized over-wintered individuals was observed especially in the interrupted site. It is expected that a large individual has the large seed quantity of production. These results indicate that conservation of V. raddeana requires promotion of not only seedling recruitment by prescribed burning which promote improvement of environment such like light condition, but also the maintenance of populations which include large individuals capable of producing seeds. Hence, fire-free intervals may be required.


日本生態学会