Sensitive Wetlands (1:50 000)

This data layer was created by Kevin Shaw. Kevin delineated wetland boundaries on 1:50,000 topographical maps. Wetlands are defined by DEA and T Wetlands Conservation Programme (August 1998 draft) as lands supporting predominantly hydrophytes, or where the substrate is predominantly undrained hydric soil, or where the substrate is non-soil and is saturated with water or covered by shallow water at time during the growing season. However, hydric soils cannot be distinguished without a detailed field visit (as suggested by the Wetland Fix Programme). Consequently, boundaries were defined with the help of aerial photographs and personal knowledge to include wetland habitats (open water, reedbeds, salt marshes, mud flats, floodplains) and dams (which are known to have a established floral and faunal component i.e. have some biological functioning and are not sterile). Boundaries where subsequently digitised inhouse (by Riki de Villiers) from the 1:50,000 topographical maps. During November 1999 Riki de Villiers added names and types to the wetlands based on 1:50,000 topographical maps. Please note that these names and types have still to be vetted by Kevin Shaw. Consequently these data should be viewed as in prep until these data have been vetted.

本数据图层由凯文·肖（Kevin Shaw）创建。凯文基于1:50000比例尺地形图勾绘了湿地边界。湿地的定义依据环境与水资源部（DEA）及T湿地保护计划（1998年8月草案），为以水生植物为主的土地，或基质以未排水的湿土为主的土地，或基质为非土壤且在生长季某一时间段处于水饱和状态或被浅水覆盖的土地。然而，若不开展详细的野外踏勘（如湿地修复计划所建议），则无法区分湿土。因此，研究人员借助航空影像与个人经验确定边界，涵盖的湿地生境包括开阔水域、芦苇荡、盐沼、潮滩、洪泛平原，以及水库（已知水库具备成熟的动植物群落，即具备一定生物功能，并非完全无生命的水体）。随后由里基·德维利尔斯（Riki de Villiers）在机构内部将上述边界从1:50000比例尺地形图上进行数字化处理。1999年11月，里基·德维利尔斯基于1:50000比例尺地形图为湿地补充了名称与类型信息。请注意，上述名称与类型信息仍需由凯文·肖进行审核。因此，在完成审核前，本数据集仍处于待完善（in prep）状态。