校庭の雑草群落の生態学的研究 : 空間構造の季節的推移と遷移

During the period from March to September in 1961, for the purpose of making clear the succession and the status of seasonal changes in the occupational space of the components, the weed vegetation on the campus of Tottori Universityb was investigated. The following commu-nities were adopted as the samples : 1.Pure communities a. Coreopsis tinctoria (annual) community b. C. tinctoria (perennial) community c. Juncus tenuis community d. Medicago hispida community e. Kummerovia striata community 2. Mixed communities a. J. tenuis-M. hispida community b. C. tinctoria-J. tenuis-M. hispida-K. striata community In the pure cummunities, C. tinctoria seems to be mightier in competition strength in the case of clusters than in the case of being solitaty. But the reverse is as to M. hispida and K. striata. Of the mixed communities, the latter community has appeared to be fairly stable for several years. This seems to be due to that this community is composed of the plants which grow uo to the maximum growth-stage in different seasons, respectively: K. striata grows up in late summer or early autumn, while the other three in early to middle summer.