New South Wales – Dryland Salinity Assessment 2000 – Assessmet of Dryland salinity extent 2000

\r\n\r\nThe data shows areas of dryland salinity risk in 2000 in the Murray-Darling\r\nBasin within NSW and coastal NSW catchments.Areas of risk are based on\r\ngroundwater levels and air photo interpretation. The merged data, at a nominal\r\nscale of 1:250 000, show actual areas where dryland salinity or water-tables\r\nless than 2 metres have been measured. For the extent map, every delineated\r\narea is underpinned by either air photo data or by one or more groundwater\r\nbores. Therefore, the area at risk is regarded as conservative due to\r\nlimitations in the spatial coverage of air photo and bore data. number of\r\ntechniques to spatially extrapolate these data to infer potential areas at\r\nrisk were trialed but were considered scientifically or statistically\r\ninadequate. Estimates of impacts are based on areas at risk having groundwater\r\nlevels of less than 2 m. An impact assessment based on groundwater less than 5\r\nm and rising was considered inappropriate. Total areas affected with\r\ngroundwater less than 5 m and rising have been presented, but only for\r\nimproved consistency with other States.\r\n\r\nSee [further metadata](http://data.daff.gov.au/anrdl/metadata_files/pa_dsa__r1in\r\n__00111a01.xml) for more detail.\r\n\r\n

本数据集展示了2000年新南威尔士州（New South Wales, NSW）境内墨累-达令盆地（Murray-Darling Basin）以及新南威尔士州沿海集水区的旱地盐碱化风险区域。风险区域的划定依据为地下水位数据与航空像片解译结果。该合并数据集的标称比例尺为1:250000，展示了经实测存在旱地盐碱化或地下水位埋深小于2米的实际区域。针对该范围地图，每一处划定的区域均有航空像片数据或一口及以上的地下水钻孔数据作为支撑依据。因此，受限于航空像片与钻孔数据的空间覆盖范围，该风险区域的统计结果被认为是保守的。相关研究人员曾尝试采用多种空间外推技术对这些数据进行处理，以推断潜在的风险区域，但相关方法在科学或统计层面均被认为不够充分。影响评估的估算基于地下水位埋深小于2米的风险区域。而基于地下水位埋深小于5米且呈上升趋势的影响评估则被认为并不恰当。本次仍给出了地下水位埋深小于5米且呈上升趋势的受影响区域总面积，但此举仅为与其他州的统计结果保持一致。
详细信息请查阅[补充元数据（Metadata）](http://data.daff.gov.au/anrdl/metadata_files/pa_dsa__r1in__00111a01.xml)。