667800 669600 671400 673200 ApEcTp ApEcTp ApEcTp ApEcTp ApEcTp ApTb ApTb EgKvPm ApEcTp ApTb ApEcTp 48 EgKvPm ! ApEcTp AaSlTp 92 SggGrTp ! SggGrTp K AaSlTp 0 0.25 0.5 AbPrIa AbPrIa Kilometres 1:15,000 LegendAbsolute Scale - 33 ! AaEm 7434000 Study Area ! 30 ApSgg EllEllTp Quadrat locations ! ApSgg Vegetation Units AaAc AaEffTp AaEm AaPoTp EgKvPmAaPoTt ApSgg ApSgg EllEllTp AaSaoTp AaTssp AaTp EllEllTp Tp ApSgg EllEllTp EllSggTw ElAmTssp AmGtTssp AmTw ApEcTp AaPoEpApTssp ExPnnTt EllEllTp AaTb EllEllTp EllEllTpSggTp AaSaoTp EllEllTp EgSggTb AaEm EllEllTp ApSgg EllEllTp EllSggTp EllEllTp ApSgg EllEllTp AaTt 7432200 AlAp PsTp SggAbTp SggIrTw Figure: 5.17 Drawn: CP Project ID: 1457 Date: 23/11/2012 Vegetation Units within the West Angelas Study Area Coordinate System Unique Map ID: CP153 Name: GDA 1994 MGA Zone 50 Map D2 Projection: Transverse Mercator Datum: GDA 1994 A3 673200 675000 676800 678600 ApEcTp ApEcTp 48 ! ApEcTp SggGrTp AaSlTpSggGrTp 102 ! SggGrTp AbPrIa Legend Study Area ! Quadrat locations 7434000 Vegetation Units AaAc AaEffTp 22 ! AaPoTp AbPrIa AaPoTt AaSaoTp 23 ! AaTssp 34 ! AaTp EllEllTp Tp EllSggTw ApSgg ElAmTssp AmTw AaEm 4 EllEllTp AaEm ! ApEcTp ApTssp EllEllTp ApSgg AaTb AbPrIa AaEm SggTp EgSggTb K EllSggTp EllEllTp 0 0.25 0.5 AaTt AaPoEp AlAp 7432200 Kilometres PsTp Absolute Scale - 1:15,000 SggAbTp SggIrTw Figure: 5.18 Drawn: CP Project ID: 1457 Date: 23/11/2012 Vegetation Units within the West Angelas Study Area Coordinate System Unique Map ID: CP153 Name: GDA 1994 MGA Zone 50 Map D3 Projection: Transverse Mercator Datum: GDA 1994 A3 685800 687600 689400 691200 !120 ChDllTt ApTb ApTb EgKvPm EgKvPm ApSgg EgKvPm EgKvPm ExPnnTt ApTb ApTb AmGtTssp EgKvPm EgKvPmChDllTt EgKvPm ApTb ApTb EgKvPm EgKvPm EgKvPm ! ChDllTt ApTb ChDllTt EgKvPm ApTb EgKvPm ChDllTt ChDllTt ChDllTt 124 ChDllTt ! ApTb ChDllTt ChDllTt AmGtTssp AbPrIa SggGrTp 111 AbPrIa ChDllTt! AbPrIa AbPrIa 113 ChDllTt 106 ! ExPnnTt AbPrIa ! AbPrIa AbPrIa AbPrIa SggGrTp AbPrIa ChDllTt SggGrTp AbPrIa AbPrIa ChDllTt AbPrIa 98 ! AaSlTp Legend SggGrTp 105 Study Area AaSlTp 110 ! ! 7434000 ! Quadrat locations 112 ! Vegetation Units ChDllTt AaAc 114 ! AaEffTp 46 AaAoAc 45 ! AaPoTp ! AaPoTt ApTb AaSaoTp AaTssp AaTp Tp EllSggTw PsAjs 108 ! AaSlTp ElAmTssp AmTw ApEcTp 51 52 ApTssp ! ! 119 AaTb ! EgKvPm SggTp EgSggTb EgKvPm EllSggTp 116 K ! EgKvPm AaTt 0 0.25 0.5 AaSlTp AlAp 7432200 PsTp Kilometres SggAbTp SggIrTw Absolute Scale - 1:15,000 Figure: 5.19 Drawn: CP Project ID: 1457 Date: 23/11/2012 Vegetation Units within the West Angelas Study Area Coordinate System Unique Map ID: CP153 Name: GDA 1994 MGA Zone 50 Map D5 Projection: Transverse Mercator Datum: GDA 1994 A3 689400 691200 693000 694800 ApSgg EgKvPm ApTb ApTb ApTb ApTb ApTb ApTb 123 EgKvPm ! 127 EgKvPmApTb EgKvPm ApTb ! 126 ApTb AmGtTssp ! ChDllTt ChDllTt EgKvPm ChDllTt 124 ! ApTb ChDllTt ApTb ApTb AbPrIa AmGtTssp 111 AbPrIa ChDllTt! 99 ApTb AbPrIa ! ChDllTt 106 ExPnnTt AbPrIa ! ApTb 107 ! 98 AaSlTp SggGrTp ! ApTb 109 ApTb AmGtTssp ! 105 Legend ! Study Area 7434000 112 ! 115 ! ! Quadrat locations ChDllTt Vegetation Units 114 ! AaAc AaEffTp ApTb AaPoTp AaPoTt PsAjs AaSaoTp AaTssp AaTp Tp EllSggTw ElAmTssp AmTw AaSlTp ApEcTp EgKvPm ApTssp AaTb SggTp 116 EgSggTb ! EgKvPm 117 118 ! EllSggTp ! EgKvPm K AaTt 7432200 0 0.25 0.5 AlAp Kilometres PsTp SggAbTp Absolute Scale - 1:15,000 SggIrTw Figure: 5.20 Drawn: CP Project ID: 1457 Date: 23/11/2012 Vegetation Units within the West Angelas Study Area Coordinate System Unique Map ID: CP153 Name: GDA 1994 MGA Zone 50 Map D6 Projection: Transverse Mercator Datum: GDA 1994 A3 Q_037 AmTw Q_038 Q_153 Q_136 Q_133 Q_002 Q_035 EllSggTw Q_156 Q_005 Q_057 Q_144 Q_132 SggIrTw Q_134 Q_143 Q_120 Q_146 Q_111 SggTp Q_112 Q_124 Q_126 Q_106 Q_142 Q_127 Q_140 Q_110 Q_149 ElAmTssp Q_040 Q_147 Q_105 Q_113 Q_056 Q_020 Q_058 Q_030 ApTssp Q_128 Q_125 Q_015 Q_036 Q_022 Tp Q_004 Q_160 Q_008 Q_092 Q_098 SggAbTp Q_100 Q_102 Q_006 Q_034 Q_023 Q_026 Q_027 Q_003 Q_103 Q_151 Q_011 EllSggTp Q_024 Q_152 Q_139 Q_017 Q_093 EgSggTb Q_122 Q_117 Q_119 Q_116 Q_108 Q_052 PsTp Q_051 Q_012 Q_047 Q_046 Q_045 Q_078 Q_009 Q_067 AaAc Q_064 Q_069 Q_089 Q_053 Q_063 Q_081 Q_049 Q_050 AaEcTp Q_200 Q_070 Q_029 Q_071 Q_044 Q_019 Q_041 Q_154 AaSaoTp Q_054 Q_080 Q_086 Q_010 Q_091 Q_077 Q_048 Q_018 AaTp Q_118 Q_115 Q_085 AaEffTp Q_065 Q_090 Q_082 Q_079 Q_060 AaTssp Q_059 Q_131 Q_042 Q_155 Q_121 Q_014 Q_016 Q_075 AaTb Q_028 Q_109 Q_107 Q_114 Q_074 Q_072 Q_025 Q_148 AaPoTp Q_033 Q_129 Q_141 Q_130 Q_087 Q_201 Q_097 Q_104 AaPoTt Q_043 Q_084 Q_096 Q_076 Q_007 Q_031 Q_099 Q_055 Q_123 Q_145 Q_138 AaTt Q_137 Q_135 Q_094 Q_062 Q_066 AlAp Q_095 Q_068 Q_061 Q_021 0.0 0.2 0.4 0.6 0.8 1.0 1.2 Figure 5.21 ‐ Dendrogram of similarities between quadrats (SYSTAT) Rio Tinto Greater West Angelas Vegetation and Flora Assessment This page has been left blank intentionally. April 2013 102 Rio Tinto Greater West Angelas Vegetation and Flora Assessment 6 DISCUSSION The significance of the vegetation and flora of the Study Area has been assessed at four scales: national, state, regional and local. National significance refers to those features of the environment which are recognised under legislation as being of importance to the Australian community. Flora species and Threatened Ecological Communities (TECs) listed under the EPBC Act are regarded as nationally significant. State significance refers to those features of the environment that are recognised under state legislation as being of importance to the Western Australian community. It includes species that are listed as Threatened under the WC Act and TECs and PECs listed by the DEC, or vegetation which supports fauna of scheduled status. Regional significance addresses the representation of species and habitats at a biogeographical level. That is, species or habitat types that are endemic to the Hamersley sub‐region or whose distributions are limited or unknown are considered regionally significant. Vegetation and flora species are of local significance when their presence is confined to a very locallised area or a specialised habitat type that is not common in the local or regional contaxt and whose disturbance or removal may lead to local extinction. 6.1 FLORISTIC RICHNESS Species richness is a fundamental measurement of community and regional diversity (Gotelli and Colwell 2001). It is the simplest representation of species diversity (Magurran 1988, Fowler and Cohen 1990) and is the basic indicator of diversity used for this survey. April 2013 103 Rio Tinto Greater West Angelas Vegetation and Flora Assessment Table 6.1 compares the floristic inventory recorded during the current survey to that recorded in other quadrat‐based surveys conducted in the Pilbara. The most directly comparable survey was in 1998 of the Turee Study Area by ME Trudgen & Associates (1998) which was also a large scale survey. In ME Trudgen & Associates a larger area was survyed, encapusulating a greater range of habitats/landsystems which also resulted in a greater number of taxa recorded. A comparison of survey intensity with that of the remaining previous projects is difficult due to the differing scales of survey sizes. The survey intensity of the current study (0.85 quadrats/km2) is considered adequate to the area surveyed; which is reflected in the high number of taxa recorded for its scale. April 2013 104 Rio Tinto Greater West Angelas Vegetation and Flora Assessment Table 6.1 – A Comparison of Floristic Richness of Study Area with Nearby Studies Number Number Number Area Quadrats Study Site Date Surveyed Quadrats Taxa of Taxa/ (km2) /km2 Surveyed Recorded km2 Current study June‐August 2012 149 175 0.85 431 2.46 ME Trudgen & Associates May‐Aug 2011 ‐ 353 1998 ‐ 635 1.80 Biota 2010 May‐12 37 10 3.70 262 26.20 Rio Tinto 2010 April‐10 17 5 3.40 184 36.80 Biota 2006 May‐04 41 19 2.16 429 22.58 6.1.1 Flora of National Significance Lepidium catapycnon is the most significant taxon with regards to conservation status recorded within the current survey and is listed as vulnerable under the EPBC Act. Descriptions of the EPBC Act vulnerability codes can be found in Appendix D. Fourteen other collection points are lodged at the West Australian Herbarium, located within Western Australia and in close proximity each other. Based on collections from the current survey, this taxon is not abundant within the West Angelas Study Area, with 29 individuals from four locations recorded, however further targeted surveys have the potential to expand the known population. There is one known location from within the conservation estate. Lepidium catapycnon appears to favour the outer edge of creek vegetation and rocky scree slopes that consist of orange‐brown (terracotta) coloured clay‐loam soil; and it is also favourable to areas where disturbance has exposed sub‐soils, particularly of the calcareous type. Thirteen other locations of Lepidium catapycnon occur regionally within 40 km of the Study Area, suggesting that the taxon is likely to occur elsewhere within the Study Area (Figure 5.9 and Table 2.8). The main threat to L. catapycnon is mining and exploration activities as its preferred habitat and the majority of recorded populations occur within mining and exploration tenements (Threatened Species Scientific Committee 2008). Processes which have been identified as potential threats to this species include roadworks, as it tends to prefer recently disturbed areas and colonises graded mining and exploration tracks (Threatened Species Scientific Committee 2008). The spread of the introduced species Ruby Dock (Acetosa vesicaria, which was also recorded within the Study Area) has been suggested to prevent establishment of this species in some areas (Threatened Species Scientific Committee 2008). 6.1.2 Flora of State Significance Lepidium catapycnon, as above, is listed as Threatened (formerly Declared Rare Flora) under the WC Act. 6.1.3 Flora of Regional Significance Thirteen Threatened and Priority Flora taxa were recorded by ecologia during the current survey: one Threatened (Lepidium catapycnon), three Priority 1 species (Aristida jerichoensis var.