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Ranking of Lakes for the purpose of enabling the prioritisation of resources to manage the current ecological values. This featureclass should be used in conjunction with other Northland Biodiversity Ranking data and in consultation with the Spatial data notes for Northland Biodiversity Ranking August 2018 (Obj Ref A1105191), Soil Types lris data dictionary (Obj Ref A1105672) and associated report "A classification of New Zealands terrestrial ecosystems by N J Singers and G M Rogers (Obj Ref A1105681).Rankings for lakes are described in a polygon shapefile (NorthlandLakeRanks.shp) that wascreated by overlaying a polygon layer delineating lakes greater than 1 ha in extent onto thelake ranking raster layer (NorthlandLakeRanks.tif) and calculating summary statistics for gridcells falling within each lake. Fields within the associated data table are as follows:a. ObjectID – a unique numeric identifier;b. LID – the lake identifier derived from the FENZ lake dataset;c. Name – the lake name where available;d. LakeAreaHa – the lake extent in ha;e. Geomorphic – the FENZ geomorphic classification group to which the lake isassigned;f. Condition – the estimated lake condition (from FENZ) with values ranging between 0(very poor condition) and 1 (very high condition);g. EcolRegion – the Ecological Region within which the lake is predominantly located –note that a small area near Mangawhai, located within the Auckland ER, wasamalgamated with the Eastern Northland ER for this analysis;h. RankMean – the average ranking, calculated by overlaying the polygons onto thecontinuous lake ranking layer;i. RankMin – the minimum (or highest) ranking occurring within the polygon,calculated as for RankMean;j. RankMax – the maximum (or lowest) ranking occurring within the polygon,calculated as for RankMean;k. RankOrder – the integer numerical rank of lakes, with values ranking from 1 (highestrank) to 295 (lowest rank);l. CumArea – the cumulative area of lakes (ha) when sorted into rank order;m. CumAreaPC – cumulative area of lakes when sorted into rank order, expressed as apercentage of all lakes. |