畠島海岸生物相の長期的変化とその要因
LONG-TERM CHANGE IN THE COASTAL BIOTA OF HATAKEJIMA ISLAND

Shunichi OHGAKI
1989 Nihon Seitai Gakkaishi  
Synops童 s Literature on the rc nt changes in thc ◎oastal biota of Hatakejima Island ( 33°41 σ N , 135022 「 E) was reviewed and possible causes of the changes were explored . S童 x hundred and twenty one spccies of animals and plants have been recerded on this island ' s seashore . Three quartcrs of them are invertebrates . The coastal biota has prominently changed in the last three decades ; 〔 舛 sp 弖 es ( > 10 % of all ) increased or decreased conspicuonsly . The number of decreasing species was
more » ... reasing species was 5 times greater than that of the increasing oncs , The decline in number of spccies was more obvious in molluscs and hinoderms than crustaceans . Water po11ution seems to be an important cause of the obscrved changes ,01igotrophic sp ics decreased and eutrophic spedes increased. Scveral species have disappeared only from the bay − head side of the island where po1lution has been serious . Some circumsta 丑tial evidenoe suggests that tho changes are also due to low temperatures in winter and harvest置 ng of edible spec 三 es by bcaI people . Key Wo 餌 ls:Hatakejima lsl {
doi:10.18960/seitai.39.1_27 fatcat:53lezsw4djaoze4qoxnqnnhc4i