@article{oai:meio-u.repo.nii.ac.jp:00001505,
 author = {新垣, 裕治 and Arakaki, Yuji},
 issue = {26},
 journal = {名桜大学紀要, THE MEIO UNIVERSITY BULLETIN},
 month = {Mar},
 note = {マングローブ類は，散布体（胎生種子，半胎生種子）が海流等に運搬され分布域を拡大する。羽地内海には，国内移入種であるヒルギダマシが分布している。ヒルギダマシの散布体（果実）は半胎生種子で，防水性の高い果皮の浮力により浮遊し分布域を広げる。本研究では，ヒルギダマシの果実を自然光周期及び連続暗黒の条件下で各処理水（海水，汽水，DW）に浸水し，果皮剥離による果実の沈降及び再浮上について調べ，同種の分散について考察をした。全ての果実の沈降までの平均時間は，自然光周期条件では6.5日，連続暗黒条件では5.4日であった。自然光周期条件では，DWへ浸水した果実が海水と汽水に比べ沈降しやすく，また，再浮上の実験では再浮上しやすかった。この違いはいずれも有意（分散分析，p<0.01）であった。海水及び汽水の処理では，自然光周期及び連続暗黒条件の両方で沈降及び再浮上の違いが無かった。再浮上果実を人工培地へ移し発根と発芽，茎の伸長があったことより，再浮上果実にも本種の分散の可能性があることが示された。, Mangroves expand their distribution by drifting floaters, viviparous and semi-viviparous seeds, and by being carried by waters such as currents. Avicennia marina, a domestic introduced species, is distributed in the Haneji inland sea. The floater, or propagule, of A. marina is a semi-viviparous seed, covered by a high waterproof pericarp that keeps its buoyancy, which enables the seed to drift for expansion of distribution. In this research, in order to consider A. marina dispersion, the sinking and re-surfacing of A. marina propagules after the shedding of the pericarp were observed, under the conditions of natural light and consecutive darkness, and with immersion treatments of the propagules in seawater, brackish water, and distilled water （DW）. The average time of all propagules under the natural light and consecutive darkness condition was 6.5 days and 5.4 days, respectively. Propagules immersed in DW under the natural light condition sank more easily than those immersed in seawater and brackish water, and more easily re-surfaced in the re-surfacing experiment. These differences were significant （ANOVA, p<0.01）. No significant differences were found between the immersion in seawater and brackish water under the conditions of natural light and consecutive darkness. Findings of re-surfacing propagules showed rooting and germination as well as stem elongation after being transferred into an artificial medium, which was an indication that resurfacing propagules have the ability to disperse the distribution of this species.},
 pages = {71--76},
 title = {沖縄島の羽地内海干潟に産するヒルギダマシ（Avicennia marina）の果皮剥離に及ぼす要因について},
 year = {2021},
 yomi = {アラカキ, ユウジ}
}