建立长江天鹅洲白鱀豚保护区的可行性研究

白豚（Ｌｉｐｏｔｅｓｖｅｘｉｌｌｉｆｅｒ）为我国特有珍稀动物，其种群数量仅２００头左右，十分濒危。为了拯救这一物种，针对白豚和长江的特点，作者选择了长江天鹅洲故道作为拟建的白豚半自然保护区，进行可行性研究。经过四年的工作，从水质理化状况、水生生物状况、鱼类资源、水体生产力以及故道周围环境等多角度，分析了天鹅洲故道的环境特征，摸清了该故道的本底，并将故道环境与长江环境进行了比较。在上述工作的基础上，又引５头江豚（Ｎｅｏｐｈｏ－ｃａｅｎａｐｈｏｃａｅｎｏｉｄｅｓ）入天鹅洲故道进行了二年的试养，并获成功。本底调查和试养江豚的结果表明，长江天鹅洲故道是建立白豚半自然保护区的理想场所。这个保护区的建立是保护白豚的一项有效、可行、必要的保护措施。

STUDIES ON THE FEASIBILITY OF ESTABLISHMENT OF A SEMI-NATURAL RESERVE AT TIAN-E-ZHOU(SWAN)OXBOW FOR BAIJI,LIPOTES VEXILLIFER

The baiji, Lipotes vexillifer is a rare and highly endangered river dolphin indi-genous to China and has a currently estimated population size of about 200 indivi-duals. On the basis of the known characteristics of baiji, and the environment of the Changjiang(Yangtze)River which is the only present-day habitat of baiji,we have proposed to establish a semi-natural reserve for the baiji at Tian-e-zhou(Swan)which is an oxbow segment of the Changiiang River near the city of Shishou in Hubei Province. This paper reports the findings from a 4-year feasibility study co-nducted by our institute on Tian-e-zhou and is mainly based on the physical and cliemical parameters of water quality monitoring,aquatic biological situation and biological productivty,fish prodution. Comparisons of our findings from the Oxbow segment and from the Changiiang River are presented.Five finless porpoises,Neophocaena phocaenoides,were introduced into the oxbow as a model testing group.After about two years'observation and monitoring,our results indicated that the oxbow is ideal as a semi-natural habitat for the fin-less porpoises.It is suggested that the oxbow may be used as a feasible semi-natural reserve for the propagation and then for the conservation of the baiji as a target species.