Indicators of Catchment Condition in the Intensive Land Use Zone of Australia – Pesticide hazard

\n\nIt should be noted that this data is now somwhat dated!\n\nPesticide (incl. herbicides, insecticides, fungicides and fumigants) use is a\ndirect measure of the input of toxins into the natural environment and is\nrelevant at property, catchment and regional scales. Pesticide use can be\nmanaged at the catchment scale through policies and/or regulations controlling\napplications, availability, etc.\n\nWaterway health is sensitive to the magnitude, frequency and toxicity of\napplications. The NLWR National Land-Use map (2001) is currently the best\navailable national coverage (1:1M). national pesticide use data set is not\navailable.\n\nEvery land-use class in the NLWR land-use map was given a pesticide rating,\nbased on the toxicity of pesticides used, frequency of application and $\nspent. Rating is based on expert opinion (J. Walcott, BRS, pers. comm.), and\nassumes that each land-use can be equated to particular pesticide usage\npatterns. standard methodology has not been used.\n\nData reliability is poor, due to the subjectivity of the rating system, the\nlack of actual pesticide data and spatial integrity of the land-use map. The\nrating of pesticide use is unequivocal a a high rating, reflecting substantial\nand frequent application and/or high toxicity, implies a high waterway\ncontamination hazard. However, the pesticide type, the method of application\nand usage has been assumed based on land-use practice, and is not an absolute\nmeasure of pesticide use. The indicator has not been validated, however it is\nwidely understood by users.\n\nNature conservation and grazing on native pastures indicate a low hazard from\npesticide. In contrast the areas of extensive cropping and the irrigation\ndistricts areas show a high application rate, with a consequent high hazard to\nland and waterway condition. The high hazard areas are concentrated in the\n800-1000mm rainfall belt west of the dividing range in SE Victoria and NSW,\nand also parts in SW Western Australia, and in Central Queensland. The\ndetailed analysis also suggests that many AWRC basins contain a wide range of\nhazard values.\n\nThe environmental linkage of pesticide hazard between sub-catchments is likely\nto be complex so area-based averaging of a hazard rating in AWRC basins may be\nmisleading. River basins with relatively high hazard ratings include:\nGreenough, Avon and Blackwood Rivers in WA; Broughton, Wakefield, Gawler and\nTorrens Rivers in SA; Wimmera a Avon, Avoca, Yarra, Maribyrnong, and Latrobe\nRivers, Tambo Rivers in Vic; in Tasmania, the Arthur and Rubicon Rivers; in\nNSW, the Sydney-Georges, Macquarie-Tuggerah Lakes, and Gwydir Rivers; and in\nQueensland, the Tully, Boyne, Calliope, Ross, Curtis Island, Maroochy,\nJohnston, South Coast and Mulgrave-Russell Rivers.\n\nData are available as:\n\n * continental maps at 5km (0.05 deg) cell resolution for the ILZ;\n * spatial averages over CRES defined catchments (CRES, 2000) in the ILZ;\n * spatial averages over the AWRC river basins in the ILZ.\n\nSee [further metadata](http://data.daff.gov.au/anrdl/metadata_files/pa_iccilr9ab\n__06221axx.xml) for more detail.\n\n