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<DIV STYLE="text-align:Left;"><P><SPAN>This spatial rivers dataset is part of the South African Inventory of Inland Aquatic Ecosystems (SAIIAE) which was released with the National Biodiversity Assessment (NBA) 2018. In the NBA 2018 the National Freshwater Ecosystem Priority Area (NFEPA) rivers GIS layer was used to represent the diversity of rivers nationally. It used the 1:500 000 river network coverage available from the Department of Water and Sanitation (DWS) and can be downloaded from the following website: http://www.dwaf.gov.za/iwqs/gis_data/river/rivs500k.aspx. This GIS layer summarizes the river ecosystem types, river condition, Ecosystem Threat Status (ETS) and Ecosystem Protection Level (EPL) as well as the free-flowing (62 identified by the NFEPA project) and flagship river information.</SPAN></P><P><SPAN /></P><P><SPAN>Publication Date: 2018</SPAN></P><P><SPAN /></P><P><SPAN STYLE="font-weight:bold;">Attribute Definitions</SPAN></P><P><SPAN>OBJECTID - System generated field, object number.</SPAN></P><P><SPAN>LENGTH - River Length (m).</SPAN></P><P><SPAN>REACHCODE - Code for reach. Corresponding to the 2007 version of the DWA 1 500 000 rivers layer generated by Mike Silberbauer.</SPAN></P><P><SPAN>UNIT_ID - Planning unit identifier. All sub-quaternaries have a unique identifier. This identifier also serves as a look-up identifier for each the biodiversity features contained in each river and wetland FEPA and fish support area. This look-up table is an Excel spreadsheet that is available on BGIS or the NFEPA data DVD that accompanies the NFEPA Atlas.</SPAN></P><P><SPAN>REACHNUM - Number for reach. This distinguishes connected river reaches within a primary river drainage system.</SPAN></P><P><SPAN>ORDER - River order.</SPAN></P><P><SPAN>MAINSTEM - Mainstem = 1 is a quaternary mainstem; the rest of the 1:500 000 rivers are tributaries that are nested within quaternary catchments.</SPAN></P><P><SPAN>NAME - Name of river as per the 2007 version of the DWA 1 500 000 rivers layer generated by Mike Silberbauer.</SPAN></P><P><SPAN>L1_ECOREGN - Dominant Level 1 Ecoregion within the sub-quaternary catchment.</SPAN></P><P><SPAN>L2_ECOREGN - Dominant Level 2 Ecoregion within the sub-quaternary catchment.</SPAN></P><P><SPAN>FLOW - Flow variability where "P" = permanent or seasonal; "E" = ephemeral.</SPAN></P><P><SPAN>GEOZONE - Geomorphic zone as calculated per slope category of Rowntree and Wadeson (1999).</SPAN></P><P><SPAN> • A = Mountain Headwater Stream</SPAN></P><P><SPAN> • B = Mountain Stream</SPAN></P><P><SPAN> • C = Transitional Zone</SPAN></P><P><SPAN> • D = Upper Foothills</SPAN></P><P><SPAN> • E = Lower Foothills</SPAN></P><P><SPAN> • F = Lowland River</SPAN></P><P><SPAN> • Z = Unclassified (Subsequently Classified In Gzlump)</SPAN></P><P><SPAN>GZLUMP - Lumped geomorphic zone used by NFEPA</SPAN></P><P><SPAN> • U (Upper Foothills) = Lumping of Classes C and D</SPAN></P><P><SPAN> • L (Lower Foothills) = Class E</SPAN></P><P><SPAN> • F (Lowland River) = Class F</SPAN></P><P><SPAN>RIVTYPE - River type used by NFEPA which comprises the level 1 ecoregion number followed by the flow (N= NOT Permanent/Flashy; P = Permanent or Seasonal), followed by the geomorphological zone (M = Mountain Stream; U = Upper Foothills; L= Lower Foothills; F = Lowland River).</SPAN></P><P><SPAN>PES1999 - DWA's present ecological state 1999 with desktop modification.</SPAN></P><P><SPAN> A = Unmodified, Natural</SPAN></P><P><SPAN> B = Largely Natural with few Modifications</SPAN></P><P><SPAN> C = Moderately Modified</SPAN></P><P><SPAN> D = Largely Modified</SPAN></P><P><SPAN> E = Seriously Modified</SPAN></P><P><SPAN> F = Critically/Extremely Modified</SPAN></P><P><SPAN>RIVCON - River condition used by NFEPA A or B is considered intact and able to contribute towards river ecosystem biodiversity targets.</SPAN></P><P><SPAN> A = Unmodified, Natural</SPAN></P><P><SPAN> B = Largely Natural with few Modifications</SPAN></P><P><SPAN> AB = A or B Above</SPAN></P><P><SPAN> C = Moderately Modified</SPAN></P><P><SPAN> D = Largely Modified</SPAN></P><P><SPAN> E = Seriously Modified</SPAN></P><P><SPAN> F = Critically/Extremely Modified</SPAN></P><P><SPAN> EF = E or F Above</SPAN></P><P><SPAN> Z = Tributary condition modelled as not intact, according to natural land cover</SPAN></P><P><SPAN>FFRID - Free flowing river identification. Each system and its tributaries has the same identifier.</SPAN></P><P><SPAN>FFRREGION - The lumped ecoregion into which free-flowing rivers fall, used to achieve representation of free-flowing rivers across the country.</SPAN></P><P><SPAN>FFRFLAGSHP - Flagship free-flowing rivers as identified through an expert review process</SPAN></P><P><SPAN> 1 = Flagship River</SPAN></P><P><SPAN> 0 = Not a Flagship River</SPAN></P><P><SPAN>PES_2018 - NBA 2018 Ecological condition category. The process involved using the Department of Water and Sanitation (DWS, 2014) Present Ecological State/Ecological Importance/Ecological Sensitivity (PES/EI/ES), also referred to as PES/EIS data, which included mainstems and tributaries at a sub-quaternary level. These desktop data were updated with data that became available between 2011 and 2017 from Reserve or Ecological Water Requirement (EWR) and Water Resource Classification System (WRCS) studies.</SPAN></P><P><SPAN>NBA2018ETS - Ecosystem threat status (ETS) of river ecosystem types: this was based on the extent to which each river ecosystem type had been altered from its</SPAN></P><P><SPAN>natural condition. Ecosystem types are categorised as critically endangered (CR), endangered (EN), vulnerable (VU) or least concern (LC), with CR, EN and VU ecosystem types collectively referred to as ‘threatened’ (Van Deventer, et al., 2019; Skowno et al., 2019).</SPAN></P><P><SPAN>NBA2018EPL - Ecosystem protection level (EPL) of river ecosystem types: river ecosystem types in protected areas needed to be in good condition rivers (A or B ecological category) to be considered as protected. Well protected, moderately protected, poorly protected river ecosystem types have at least 100%, 50%, 5% of their biodiversity target in protected areas and in natural or near-natural ecological condition; not protected river ecosystem types have < 5% (Van Deventer, et al., 2019; Skowno et al., 2019).</SPAN></P><P><SPAN>FFRID_2018 - Free-flowing river ID. Each system and its tributaries has the same identifier. Where ID = 0 not a free-flowing river; all other numerics are free-flowing rivers.</SPAN></P><P><SPAN>FRFAG_2018 - In NBA 2018 where no river condition changes were recorded the free-flowing/flagship rivers remained unchanged. 1 = flagship river 0 = not a flagship river.</SPAN></P><P><SPAN /></P><P><SPAN /></P><P><SPAN /></P><P><SPAN /></P></DIV> |