生物地理学的新进展

近３０年来，生物地理学的发展极为迅速。由于遗传学和生态学的介入，生物区系的研究由描述走向解释、分析。历史生物地理学中离散观点的兴起，不仅能对生物地理分布格局的形成过程作出客观的解释，也可对地球的演化提出生物学家的看法。     

替代学派生物地理学几种研究方法简介

历史生物地理学就其基本原理、概念和研究方法可大致分为以过程为导向的传播学派和以式样为导向的替代学派。本文简要介绍替代学派的一些基本原理和概念,对最近半个世纪以来发展的几种替代学派生物地理学方法：泛生物地理学、更新世森林避难所理论、分支生物地理学以及特有性的简约性分析法的原理、方法作了简要的介绍和评论。     

历史生物地理学的进展

近年来历史生物地理学的进展主要是隔离分化学派的进展。对隔离分化学派的几个分支学派,特别是分支生物地理学和泛生物地理学在理论和方法方面的进展作了简要回顾和介绍。最近十年来分子手段广泛应用于历史生物地理学研究的各个方面,尤其是谱系生物地理学的快速崛起是历史生物地理学的一个明显特征。对本学科的发展做了初步的展望。     

历史生物地理学进展

生物地理学研究动植物的地理分布。历史生物地理学重建生物区系历史。分替理论的复兴动摇了散布理论的上百年统治。最近10年主要是分替理论推动了历史生物地理学,出现了多个途径——种系发生物地理学、分支分替生物地理学、特有性的俭吝分析和泛生物地理学。岛屿生物地理学理论有了改进和严格的实验检验;庇所学说产生了新的模型。最后就我国如何发展生物地理学提出了对策措施。     

生物地理学（一）

一、引言 生物地理学研究生物的地理分布。探险家冯·洪堡(Von Humboldt, A, 1769—1859)是最早使用生物地理学(biogeography)一词的学者之一。他根据环境的温度、海拔和纬度等物理因子解释动、植物的分布。生物地理学以前只是描述和解释自然界和生物界之间的关系,在地理学和生物学之间占据一个不明确的领域。对生物地理学感兴趣的主要是生物学家,生物学家有时用地球物理学的理论来解释动植物为什么生活在某个地方。     

外生菌根真菌生物地理学研究进展

外生菌根真菌对植物矿质营养、生态系统物质循环、物种演化进程等具有十分重要的作用,但其生物地理学研究长期滞后于动植物。扩散和隔离是解释外生菌根真菌生物地理分布格局的重要理论。古地质、古气候和宿主植物是外生菌根真菌地理分布格局形成的重要推动因子。基因组学、生物信息学技术与生物地理学方法相互结合和补充,可以用来研究一些复杂的真菌生物地理学问题。文中详细阐述了外生菌根真菌生物地理学研究的重要过程和现状,如真菌物种界定、常用数据分析方法、起源和演化规律及其在生物多样性保护方面的应用等,并初步探讨了其未来的发展方向。     

生物地理学（二）

三、生物地理学的数种研究方法 分支图解(cladogram) 要分析生物地理学的模式必需先确定:有哪几类生物,以及这几类生物之间的亲缘关系。这可以用一个分支图解(图4)来表示。假设有     

生物地理学理论的发展

生物地理学是一门占老而又年轻的学科,近几十年来又获得了新的发展。本文较详尽地介绍了该学科的基本思想和基本研究方法,并对生物地理学理论发展的历史和各种理论的基本论点及理论假说进行了重点讨论。此外,作者对该学科的发展提出了自己的思考。     

根瘤菌生物地理学的研究进展

根瘤菌是一类革兰氏阴性菌,能与特定的宿主植物共生形成根瘤,将空气中的分子态氮转变为植物可以利用的氨态氮。研究根瘤菌的生物地理分布格局及形成机制,不仅具有理论上的意义,还对根瘤菌接种剂的选择具有指导意义。目前,随着分子生物学技术的发展,以及根瘤菌多样性研究数据的积累,根瘤菌生物地理学取得了较大的进展。本文综述了根瘤菌生物地理学的研究方法及现状,并对今后的重点研究方向作了展望。     

Biogeography of rotifers

The biogeography of rotifers is discussed in light of general biogeographical concepts. It is argued that, in spite of considerable abilities for passive dispersal, vicariance can develop well in this group. Examples selected from the Branchionidae illustrate the high levels of endemicity found in Australia and South America, while the Indian subcontinent and Africa have a predominantly cosmopolitan fauna. An explanation for these patterns is found in drifting continents and Pleistocene climatic changes.     

Protist Biogeography1

Autecology (cellular organelles and secretions, encystment and dispersal abilities), environmental conditions (physiological tolerances and interaction with other organisms), and evolutionary history contribute to protist biogeography, which manifests ecological and historical aspects. Ecological biogeography is seen in the influence of geochemistry on the distribution of fresh-water phytoflagellates and algae, and of moisture and vegetation type on soil-litter protists. A temporal feature is often present because many protists encyst and respond only to certain ranges of temperature and organic content. Historical biogeography has occurred by radiative host evolution on symbiotic protozoa (e.g., termite flagellates and rumen ciliates), and by the isolating effects of water currents, temperature, and density gradients on oceanic protists (coccoliths, dinoflagellates, foraminifera, radiolaria, and tintinnines). These two aspects combine in protists living on animal surfaces. Humans affect protist biogeography by increasing parasite ranges through human migrations and by water pollution. They can diminish these situations by disease control and exploiting appropriate ciliates in sewage disposal. Many free-living protozoa appear to be cosmopolitan, but mating types and isoenzyme studies suggest that speciation with its geographic connotations may be more widespread than presently appreciated.     

Biogeography of Alaskan seaweeds

A recent survey of seaweed specimens collected in Alaska over the past two centuries, together with the application of molecular techniques to recent collections, has revealed a surprisingly diverse flora given the history of glaciation, large areas of unsuitable habitat, and otherwise harsh environmental conditions. The number of recognized species has increased from 376 in 1977 to about 550 today. Species show a variety of biogeographic patterns: species that occur primarily to the south and have their northern limit in Alaska, species that occur primarily to the west and have their eastern limit in Alaska, species that are primarily Atlantic but extend through the Arctic to Alaska, and a number of endemics. Within these broad distribution patterns are more localized patterns often involving disjunctions. These disjunctions, the occurrence of endemic species, patterns of genotype distributions, and the overall richness of the seaweed flora support the idea that marine refugia must have existed in Alaska during Pleistocene glaciations.     

Biogeography of Indonesian snakes

The islands of eastern Indonesia occupy the major zone of contact and overlap between the reptile faunas of the Asian and Australo–Papuan regions. A survey of reptiles on twenty-eight islands in eastern Indonesia between 1988 and 1993 has documented several major range extensions and many new records of species on islands. The zoogeographic affinities of the snakes of Indonesian islands are re-examined in the light of both recent surveys and taxonomic research and coupled with that published previously. The major boundary in the snake fauna of Indonesia occurs between Sulawesi and the Lesser Sunda islands to the west and the northern and southern Maluku group of islands to the east; it corresponds to the major biogeographic boundary known as Weber's Line. The biogeographic affinities of the snakes of the Tanimbar islands are equivocal. The snake fauna of islands within the Lesser Sunda group indicate that separation between islands during the Pleistocene played a role in determining current assemblages and variation within species The islands of eastern Indonesia form biogeographic subregions that have relatively high levels of endemism and evidence of incipient speciation as a consequence of changes in sea-levels and climate during the Pleistocene.