HEVAE Vegetation Groundwater Dependent Ecosystems Value - Lachlan

NSW DoI Water has adopted the Guidelines for Identifying High Ecological Value Aquatic Ecosystems (HEVAE) framework developed by the Australian Commonwealth Government. In the current assessment for NSW, the HEVAE consists of four key criteria which include diversity, distinctiveness, naturalness and vital habitat. Therefore, the HEVAE vegetation GDE value layer is a combination of four individual criterion layers. The final or overall HEVAE score was determined for vegetation PCT polygons which has a high probability of being groundwater dependent. This was calculated by adding together the final scores for each criterion (Naturalness, Diversity, Distinctiveness and Vital Habitat). This score was then standardised by dividing by the maximum combined HEVAE score for a whole catchment’s vegetation GDE polygons to provide an even spread of score outcomes between 0 (lowest) and 1 (highest). For ease of data modelling and management, the dataset was divided into the following catchment management areas; Border Rivers-Gwydir, Central Tablelands, Central West, Hawkesbury-Nepean, Hunter-Central Rivers, Lachlan, Lower Murray Darling, Murray, Murrumbidgee, Namoi, Northern Rivers, Southern Rivers, Southern Tablelands, Sydney Metro and Western Division (MDB and far west subdivided further into the IBRA Sub regions).

新南威尔士州水务部（NSW DoI Water）采用了澳大利亚联邦政府制定的高生态价值水生生态系统（High Ecological Value Aquatic Ecosystems，HEVAE）识别指南框架。在当前针对新南威尔士州的评估工作中，高生态价值水生生态系统框架包含四项核心判定标准，分别为多样性、独特性、自然性与关键生境。因此，高生态价值水生生态系统框架下的地下水依赖型（Groundwater Dependent，GDE）植被价值图层，由四项独立的标准图层组合构成。针对地下水依赖概率较高的植被百分比（Percent，PCT）多边形，可计算得到最终的高生态价值水生生态系统综合评分：该评分通过将自然性、多样性、独特性与关键生境四项标准的最终得分相加求和得到。随后，以单个流域内全部地下水依赖型植被多边形的高生态价值水生生态系统最大综合评分为分母，对该评分进行标准化处理，使最终得分均匀分布在0（最低）至1（最高）的区间内。为便于数据建模与管理，本数据集被划分为以下流域管理分区：边境河流-格威迪尔、中部台地区、中西部地区、霍克斯伯里-尼皮恩、亨特-中部河流区、拉克兰、下墨累-达令、墨累、马兰比吉、纳莫伊、北部河流区、南部河流区、南部台地区、悉尼都会区与西部片区（其中墨累-达令盆地（Murray-Darling Basin，MDB）与远西部片区进一步细分为澳大利亚临时生物地理分区（Interim Biogeographic Regionalisation for Australia，IBRA）亚区）。