Factors influencing seasonal changes in the respiration of Drepanopus bispinosus (Copepoda:Calanoida) in Burton Lake, a marine derived saline lake in the Vestfold Hills, Antarctica

• Main Author: Zipan Wang
• Format: Report
• Language: English
• Published: Second Institute of Oceanography, State Oceanic Administration 1995
• Subjects: 59(26); East Antarctica; Vestfold Hills; Vestfold; Burton; Saline Lake; Burton Lake; Antarc*; Antarctica
• Online Access: https://nipr.repo.nii.ac.jp/?action=repository_uri&item_id=8889; http://id.nii.ac.jp/1291/00008889/; https://nipr.repo.nii.ac.jp/?action=repository_action_common_download&item_id=8889&item_no=1&attribute_id=18&file_no=1

東南極の塩湖に生息するかいあし類の一種Drepanopus bispinosusの雌成体の冬季および夏季の酸素消費量を測定した。測定は種々の水温, 塩分, 溶存酸素量, および餌濃度の実験条件下で行った。呼吸量は水温の上昇とともに増大するが, とくに, 生息水温(0±2℃)から致死水温(13.1℃)範囲で顕著な呼吸量の増大がみられた。8月から12月にかけての呼吸量のQ_<10>値は1.65-1.89の範囲にあったが, 1月には3.11-3.32に増大した。通常の生息塩分濃度(37.2-39.5‰)で呼吸量は最も低く, それより高塩分あるいは低塩分で増大した。溶存酸素量および植物プランクトン濃度もまたある程度呼吸量の変化に影響をあたえているらしいことが推測された。8月から1月にかけてD. bispinosusの雌成体の呼吸量は連続的に減少する傾向を示した。この呼吸量の減少は繁殖期には繁殖活動の結果によるものであり, 繁殖期以降は老衰による生理的機能の低下に起因しているものであることが示唆された。 Oxygen consumption of adult females of Drepanopus bispinosus living in a marine derived saline lake in East Antarctica was measured under different conditions of temperature, salinity, dissolved oxygen and food concentration both in winter and summer. Variations in respiration paralleled temperature changes, particularly when the animals were in temperatures higher than in the normal habitat (0±2℃) and below the upper thermal limit (13.1℃). The Q_<10> values for respiration lay between 1.65 to 1.89 from August to December, but increased to 3.11 and 3.32 in January. Respiration also increased when the animals were subjected to salinities either higher or lower than normal habitat conditions (37.2-39.5‰). Oxygen consumption appeared to be related to the dissolved oxygen content and to some extent to the concentration of phytoplankton cells in the medium. The seasonal variation in respiration of adult females D. bispinosus revealed a tendency to decrease continually from August to January. This might have resulted from their reproductive activities during the period of their reproduction. Food concentration, as well as dissolved oxygen, were possible environmental factors influencing oxygen consumption. After that, it could have been mainly related to decline of their physiological functions resulting from senescence.