Tasmania - CRA/RFA - Forests - National Estate - Flora Centres of Endemism

Endemic plants provide an important insight into the process of evolution of flora and are of direct relevance to National Estate criterion A1: Importance in the evolution of Australian flora, fauna, landscapes or climate.\n\nIn some cases, where concentrations of endemic taxa occur, the role of climatic refugia in speciation during periods of climate change becomes apparent. In other cases, endemism is high without any apparent link to refugia: biogeographic determinants such as terrestrial and oceanic climatic influences, soils and localised topographic variation may be the main controlling factors in these cases. \n\nThe degree of endemism of flora is pronounced in Tasmania, a consequence of a variety of factors, such as Pleistocene glaciations and deglaciations and periodic isolation when sea-level fluctuations caused the closing of the land bridge across Bass Strait. More than 300 higher plant taxa are endemic in the region. Endemism is moderate at the generic level; for example, there are 10 endemic, mostly monotypic, angiosperm genera. Lower levels of endemism are seen in lichens, mosses and ferns. \n\nThis database describes the centres of endemism of flora, i.e. areas where concentrations of exclusively Tasmanian flora species are found. \n\nCentres of endemic flora are coded with a unique number and the relevant National Estate value and criterion. The data are mapped at 1:500,000 scale.\n\nThis is an archived dataset jointly owned by the Commonwealth and the Tasmanian Governments under the Tasmania-Commonwealth Regional Forest Agreement (RFA) data agreement of 8th November 1997.This data is available to the public under licence from the Department as part of the Commonwealth Spatial Data Access and Pricing Policy.\n\nAny reproduction of this dataset must carry the following statement:\nCopyright Commonwealth of Australia and Tasmanian Government 1998.\nDepartmental Deed

特有植物（endemic plants）为植物区系演化进程提供了重要视角，且与澳大利亚国家遗产（National Estate）准则A1直接相关——该准则聚焦澳大利亚动植物、景观或气候演化中的重要意义。

在部分区域，特有分类群集中分布，气候变化时期气候避难所（climatic refugia）在物种形成中的作用便会显现；而在另一些情形中，植物区系特有性程度较高却与避难所无明显关联，此时陆地与海洋气候影响、土壤特性及局地地形变化等生物地理决定因素或为主要调控因子。

塔斯马尼亚的植物区系特有性程度显著，这源于多种因素，比如更新世冰期、冰消作用，以及海平面波动导致巴斯海峡陆桥闭合时出现的周期性隔离。该区域现有300余种高等植物分类群为特有种。属级水平的特有性程度中等，例如存在10个特有被子植物属，其中多为单型属。地衣、苔藓与蕨类的特有性程度则相对较低。

本数据库旨在记录植物区系特有中心——即仅分布有塔斯马尼亚本土植物物种的集中区域。

植物区系特有中心均以唯一编号及对应的澳大利亚国家遗产价值与准则进行编码标注。本数据集按1:500000比例尺进行制图。

本数据集为存档数据集，由澳大利亚联邦政府与塔斯马尼亚州政府依据1997年11月8日签署的《塔斯马尼亚-联邦区域森林协定（RFA）》数据协议共同拥有。根据联邦政府空间数据获取与定价政策，公众可通过相关部门许可获取本数据。

任何对本数据集的复制行为均需附带以下声明："版权所有：澳大利亚联邦政府与塔斯马尼亚州政府，1998年。部门契约（Departmental Deed）"