塔里木盆地鱼类生物地理学初步解析

Analysis of Biogeography of Fishes in Tarim Basin

塔里木盆地与青藏高原地理位置邻近,但地形地貌、气候水文差别显著,而两地的鱼类区系组成却均以裂腹鱼和高原鳅为主。本文依据现代生物地理学研究方法,以裂腹鱼和高原鳅的起源与演化为线索,结合塔里木盆地的地质、气候变迁,探究塔里木盆地鱼类空间分布格局形成原因及过程,研究塔里木盆地与青藏高原两地间鱼类的关系。结果显示:中新世晚期至上新世末塔里木盆地出现的从外围山地向沙漠腹地流向的水文网雏形,使不同进化水平的裂腹鱼和高原鳅在以后不同的地质时期陆续随地表径流从青藏高原(昆仑山)、天山等塔里木盆地周边山地进入该盆地成为可能。扁吻鱼Aspiorhynchus laticeps(Day)、塔里木裂腹鱼Schizothorax(Racoma)biddulphi Günrher、叶尔羌高原鳅Triplophysa(Hedinichthys)yarkandensis yarkandensis(Day)、隆额高原鳅T.(T.)bombifrons(Herzenstein)和长身高原鳅T(Triplophysa)tenuis(Day)5种鱼类可能是裂腹鱼类和高原鳅类某些较为原始的类群在晚中新世-早更新世进入塔里木盆地,在地理隔离下,趋异进化适应辐射形成的物种。宽口裂腹鱼S.(Schizothorax)eurystomus(Kessler)、扁嘴裂腹鱼S.(R.)esocinus Heckel、厚唇裂腹鱼S.(R.)irregularis Day、重唇裂腹鱼S.(R.)barbatus Mcclelland、斑重唇鱼Diptychus maculatus steindachner、新疆裸重唇鱼Gymnodiptychus dybowskii(Kessler)、斯氏高原鳅T.(T.)stoliczkae(Steindachuner)7种鱼类可能发生在塔里木盆地周边的山地及青藏高原,第四纪陆续进入塔里木盆地。进入塔里木盆地的鱼类在环境的选择压力下、种间和种内的竞争中,受多重因子的共同作用,逐步形成近现代的区系及空间分布格局。塔里木盆地和青藏高原两地主要的鱼类起源的种类和时间基本一致,演化发生的地区地形、气候显著不同,形成了区系结构相似、种类组成各具地域性的特点。近50年来,受灌溉引水、筑坝发电等人为影响,塔里木盆地鱼类资源量迅速衰减,分布范围大幅缩小。

This paper describes a detailed study of the origin and distribution of fishes in Tarim Basin to explain why and how the abo- riginal fish distribute in Tarim Basin based on the evolution of Tarim Basin＇ s climate and geology as well as the origin and evolution of Schizothoracinae and Triplophysa fish. This study indicate that the prototype of the hydrological network appeared in Tarim Basin about late Miocene to late Pliocene makes it possible which different evolutionary levels of Schizothoracinae and Triplophysa fish entered into Tarim Basin from the surrounding mountains in different geological periods. Speciation of the 5 species, Aspiorhynchus laticeps （Day）, Schizothorax （Racoma） biddulphi Gtinrher, Triplophysa （Hedinichthys ） yarkandensis yarkandensis （Day）, T. （T.） bombifrons （Herzenstein）, and T. （T.） tenuis （Kessler）, are in internal Tarim Basin, and speciation of the other 7 species, Schiorhorax （Schlzothorax） eurystomus （Kessler）, S. （R. ） esocinus Heckel, S. （R. ） irregularis Day, S. （R. ） barbatus Mcclelland, Diptychus maculatus steindachner. Gymnodiptychus dybowskii （Kessler）, and T. （ T. ） stoliczkae （ Steindachuner）are in edge of Tarim Basin. T arim Basin and the Qinghai-Xizang Plateau has the basic same types and time of fish origin and evolution, and significantly different terrain, climate. Thus, there are same fish species community structure and different fish composition in the Tarim Basin. In the past 50 years, fish resources are attenuated rapidly and the distribution area is significantly reduced due to irrigation diversion, and power generation.