5.3
Significant Flora
A number of range extensions were recorded. Most of these were additions to the known extent of a
distribution and not a new disjunct population. Two prominent examples include - Eremaea ebracteata
var. ebracteata and Olearia revoluta. Eremaea ebracteata var. ebracteata is usually found in the
northern part of the Irwin district (Hnatuik 1993), so this recording is a 100 km range extension south,
although possible as the southern extent of this species was not defined. Previously, Olearia revoluta (a
daisy) had been recorded by the Western Australian Herbarium as occurring to the east of Geraldton.
This collection represents a range extension of approximately 60 km to the south west. However, this
species is expected to occur in these parts (Blackall and Grieve 1982).
5.4
Vegetation
A total of 24 plant communities were recorded in the Aviva survey area and in the mapped areas of
Lake Logue Nature Reserve (Figures 1 and 2, Mattiske Consulting Pty Ltd 2006, Mattiske Consulting
Pty Ltd 2009). The remaining areas consist mainly of cleared paddocks, with localised remnant trees.
Listing of species in each community is in Appendix E.
C1 -
Low open Forest of Casuarina obesa over Tecticornia indica subsp. bidens and mixed
invasive herbs on flats on white/grey sand.
E1 -
Low Woodland of Eucalyptus todtiana and Nuytsia floribunda over Adenanthos cygnorum
subsp. cygnorum, Eremaea beaufortioides var. lachnosanthe, Melaleuca leuropoma, Banksia
sphaerocarpa var. sphaerocarpa and Hibbertia hypericoides on sand.
14.
URS0808/195/08
M
ATTISKE
C
ONSULTING
P
TY
L
TD
E2 -
Low Woodland of Eucalyptus accedens and Eucalyptus eudesmioides over Hibbertia spicata
subsp. spicata, Allocasuarina campestris and Melaleuca leuropoma on sandy gravel.
E3 -
Woodland and Open Woodland of Eucalyptus camaldulensis var. obtusa over Melaleuca
viminea subsp. viminea, Acacia saligna, Melaleuca lateriflora subsp. acutifolia and
Macrozamia fraseri on sandy loam.
E4 –
Open Low Woodland of Eucalyptus todtiana and Nuytsia floribunda over Banksia menziesii
and Stirlingia latifolia on sandy drainage lines.
E5 -
Open Low Woodland of Eucalyptus todtiana, Nuytsia floribunda over Banksia menziesii and
Conospermum triplinervium on sandy uplands.
E6 -
Open Low Woodland of Eucalyptus todtiana and Nuytsia floribunda over mixed low shrubs
and herbs on sandy lowlands.
E7-
Low Woodland of Eucalyptus camaldulensis var. obtusa over Melaleuca rhaphiophylla and
mixed herbs with occasional Casuarina obesa on flats on white/grey sand.
E8-
Low Woodland of Eucalyptus camaldulensis var. obtusa and Banksia prionotes over mixed
shrubs over *Bromus sp. and *Ehrharta sp. on lower and mid-slopes on white/grey sand.
F1-
Tall Shrubland of Melaleuca rhaphiophylla over Tecticornia indica subsp. bidens and other
shrubs and sedges on minor flowlines on grey/white sand.
F2-
Low Open Shrubland of Tecticornia indica subsp. bidens with mixed herbs and grasses on
flats on grey/white sand.
H1 -
Mixed Heath of Melaleuca leuropoma with emergent Banksia species with occasional
Eucalyptus todtiana and Actinostrobus arenarius on sand with exposed lateritic rises.
H2 -
Heath or Low Shrubland of Conospermum triplinervium, Verticordia nitens, Adenanthos
cygnorum subsp. cygnorum, Stirlingia latifolia and Jacksonia floribunda on sand.
H3 -
Heath or Scrub of Melaleuca leuropoma, Banksia sphaerocarpa var. sphaerocarpa,
Dryandra nivea subsp. nivea, Eremaea beaufortioides var. lachnosanthe and Hibbertia
subvaginata on lateritic rises.
H4 -
Mixed Heath of Proteaceae and Myrtaceae spp. with occasional Eucalyptus todtiana on sand.
H5 -
Mixed Heath or Shrubland of Xanthorrhoea drummondii, Allocasuarina humilis and
Hibbertia spp. and Proteaceae spp. on lateritic uplands.
S1 -
Open Scrub of Acacia blakelyi and Hakea psilorrhyncha over Gahnia trifida, Melaleuca
leuropoma, Conostylis aculeata subsp. breviflora, *Ursinia anthemoides, *Trifolium
campestre and *Vulpia bromoides on rehabilitated land.
S2 -
Open Scrub of Acacia blakelyi with occasional Eucalyptus todtiana over annual grasses and
herbs.
S3-
Tall Open Shrubland of Banksia prionotes over mixed shrubs and herbs; Acacia blakeyi in
high numbers within fire disturbed areas on crests of dunes, mid- slopes and swales on
white/grey sand.
T1 -
Scrub or Thicket of Banksia attenuata, Banksia menziesii over Banksia sphaerocarpa var.
sphaerocarpa, Adenanthos cygnorum, Banksia hookeriana and Conospermum triplinervium
on sand.
15.
URS0808/195/08
M
ATTISKE
C
ONSULTING
P
TY
L
TD
T1(d)-
Significantly Disturbed T1 community
T2 -
Thicket or Scrub of Acacia blakelyi over Melaleuca leuropoma, Banksia sphaerocarpa var.
sphaerocarpa, Verticordia densiflora var. densiflora on sand.
T3 -
Thicket or Scrub of Melaleuca hamulosa, Melaleuca concreta, Viminaria juncea and Kunzea
recurva on sand or loam flats.
T4 -
Thicket or Scrub of Melaleuca rhaphiophylla and Melaleuca lanceolata over sedges and
rushes on low-lying sandy loams.
T4(d) -
Significantly Disturbed T4 community
T5 -
Scrub or Thicket of Banksia attenuata and Banksia menziesii over Eremaea beaufortioides,
Hibbertia hypericoides, Melaleuca systena, Stirlingia latifolia and herbs with occasional
Xylomelum angustifolium on slopes and swales and flats on white/grey sand.
All of these communities extend outside the project area; however the extent of these communities in
the region have been modified by agricultural activities and mining activities. The condition of the
vegetation (based on the Bush Forever condition ratings) ranges from completely degraded in the
pastures to excellent in the bushland areas.
5.5
Conservation Status of Vegetation
5.5.1
Threatened Ecological Community
The database query of DEC revealed one Threatened Ecological Community as occurring in the region.
This TEC is the Ferricrete Floristic Community - Rocky Springs type. Community 72 Ferricrete
Floristic Community is listed as Vulnerable by the Department of Environment and Conservation
(2006), however is not listed under the EPBC Act 1999. Five examples of this TEC were listed and all
occurring approximately 1.5 km from the CWC along Rocky Springs Road. Neither of the proposed
Aviva projects directly impact of these TEC’s however, there is debate as to whether groundwater
drawdown will affect these communities.
The H1 heath community included pockets of lateritic rises, and therefore has some species in common
with the only known Threatened Ecological Community in the Eneabba area, the Ferricrete Floristic
Community - Rocky Springs type. Community 72 Ferricrete Floristic Community is listed as
Vulnerable by the Department of Environment and Conservation (2006). This Threatened Ecological
Community is not currently listed under the Commonwealth EPBC Act 1999. On the basis of database
search and a comparison with regional datasets (Department of Environment and Conservation 2009a),
the majority of the flora recorded on the Rocky Springs Ferricrete communities are represented either
on the northern Swan Coastal Plain or in the adjacent regions.
Twenty-nine of the sixty taxa recorded within the local TEC Ferricrete Community (Hamilton-Brown et
al. 2004) were recorded within the survey area (Appendix F). The majority of these species occur more
widely, and therefore the significance of the latter is difficult to assess in view of the lack of regional
studies on the Rocky Springs TEC. The project as proposed does not impact directly on the Rocky
Springs TEC (Figure 1).
Table 3:
Threatened Ecological Communities found in the Eneabba area
General Description
DEC (2006) Category
Status (EPBC Act
1999 Category)
72. Ferricrete Floristic Community
Vulnerable
-
16.
URS0808/195/08
M
ATTISKE
C
ONSULTING
P
TY
L
TD
As indicated by Blandford (pers. comm.), the ferricrete layer extends well beyond the designated Rocky
Springs TEC location. The latter raises two critical issues, firstly it raises questions on how the TEC
was defined and secondly what is the actual extent of the TEC as interpreted by the Department of
Environment and Conservation (2009b). Currently the data available on the TEC is relatively restricted
(Hamilton-Brown et al. 2004) and as there are four communities between the located TEC and the
exposed ferricrete (located east of the designated TEC site there is confusion over the significance of
the TEC).
5.5.2
Communities of Regional and Local Significance
Half of the communities described as occurring in the Coolimba Power Station Project and Central
West Coal Project have either regional or local significance as they are known habitats for Rare and
Priority Species (EPA 2004) or may reduce the local extent of these communities below 30 %. The
direct impact on these communities and each community’s significance is summarized below (Table 4).
Both the Coal West Project and Coolimba Power Station Project will reduce communities E5, E6, H1,
H5, S1, and T2 to 30 % or less of their immediate distribution.
Table 4: Summary of Vegetation types to be directly impacted within the survey area by the
proposals (CWC- Central West Coal, CPP – Coolimba Power Project)
Type
Significance
Total area
surveyed (ha)
Percent cleared
Percent outside of
Direct Impact
CPP
CWC
C1
5.848
0
0
100
CL/D
1713.986
25.28
48.892
25.828
E1
Local
38.943
0
20.504
79.496
E2
Local
18.13
0
0
100
E3
5.414
0
0
100
E4
Local
89.328
9.883
32.907
57.21
E5
Local
18.426
0
77.24
22.76
E6
Local
47.868
0
72.691
27.309
E7
9.059
0
0
100
E8
9.209
0
0
100
F1
17.662
0
0
100
F2
5.769
0
0
100
H1
Local
52.855
0
93.278
6.722
H2
Local
163.261
0
41.431
58.569
H3
Local
625.22
0.963
67.872
31.165
H4
121.861
0
0.353
99.647
H5
Local
17.898
0
88.694
11.306
S1
Local
6.24
0
100
0
S2
18.928
0
52.007
47.993
S3
62.85
0
0
100
T1
Regional
720.431
4.384
23.555
72.061
T1(d)
9.318
0
0
100
T2
Local
32.538
0
79.635
20.365
T3
35.552
0
9.002
90.998
T4
70.915
0
6.675
93.325
T4(d)
23.534
0
0
100
T5
151.272
0
0
100
Total
2118.443
-
-
-
17.
URS0808/195/08
M
ATTISKE
C
ONSULTING
P
TY
L
TD
5.6
Groundwater Dependent Ecosystems
An assessment was undertaken on the potential Groundwater Dependent Ecosystems (GDE) in and near
the project area. The heath and scrub communities (H2, H3 and T1) that dominate the vegetation of the
survey area are largely characterised by shallow-rooted species or shrubs that are primarily reliant on
the soil moisture levels being maintained by rainfall events. The two communities that may be
susceptible to groundwater drawdown are summarized below:
T4 -
Thicket or Scrub of Melaleuca rhaphiophylla and Melaleuca lanceolata over sedges and
rushes on low-lying sandy loams. This vegetation type was recorded in the northern part of
the survey area (within the northern part of Project Area and within Lake Logue Nature
Reserve). This community is dominated by Melaleuca spp. , which have both deep roots
and shallower lateral roots, and so should be able to access soil moisture from the
unsaturated above the groundwater table. This suggests that this community should display
facultative dependence on groundwater.
E3 -
Woodland and Open Woodland of Eucalyptus camaldulensis var. obtusa over Melaleuca
viminea subsp. viminea, Acacia saligna, Melaleuca lateriflora subsp. acutifolia and
Macrozamia fraseri on sandy loam. This plant community was recorded in the southern
part of the survey area and outside of the Project Area. It is considered that paperbark
swamps (Melaleuca spp.) and River Red Gums (Eucalyptus camaldulensis) probably
exhibit an facultative dependence on groundwater (Murray et al. 2003), which means that
the presence or absence of groundwater is not critical to the presence of species within an
ecosystem but that factors such as landscape position more strongly influence the sources
of water used by the species.
The community types H4, T1 and T5 (Mattiske Consulting Pty Ltd 2009) dominate the south-eastern
corner of the Lake Logue Nature Reserve. The Eucalyptus camaldulensis var. obtusa woodlands
around Lake Indoon have already been subjected to various periods of varying drought.
The other key area appears to be the nearby Rocky Springs Ferricrete TEC. This TEC occurs outside
the Project Area. On the basis of the high proportion of plant root systems in the upper 30 to 40cm of
the surface and the absence of deep tap rooted species, it appears that the vast majority of the plant
species within the different communities are reliant on soil moisture from rainfall events. This
proposition was discussed with Doug Blandford and after reviewing the soil profiles in nearby areas it
was decided that the plants would be largely reliant on the soil moisture in the sandy and sandy-clay
environments and that therefore the risk to the flora and vegetation within the Rocky Springs Ferricrete
TEC was very low.
To extend this interpretation to the flora and vegetation on the other sections of the survey area, the
lifeforms of the respective plant species was extracted from Paczkowska and Chapman (2000) and the
West Australian Herbarium (2009). This lifeform data is presented in Appendix B and as such reflects
the high proportion of annual and perennial herbs and shrub species that are unlikely to be dependent on
soil moisture from deeper sources and ground water.
6.
DISCUSSION
The survey effort was undertaken in the spring months of 2005, 2006, 2007 and 2008 by experienced
botanists familiar with the Kwongan flora near Eneabba. The specific work undertaken by Mattiske
Consulting Pty Ltd in the spring months of 2005, 2006, 2007 and 2008 included a search for rare and
priority flora, defining and mapping the plant communities present, assessing the condition of the plant
communities and reviewing the local and regional conservation value of the flora and vegetation.
Detailed recordings were undertaken at representative plant communities. The survey effort over
multiple seasons and with average rainfall (Table 1) meets the standards for the EPA Guidance
Statement 51.
18.
URS0808/195/08
M
ATTISKE
C
ONSULTING
P
TY
L
TD
Flora
A total of 512 taxa (including subspecies and varieties) from 182 genera and 64 families were recorded
within the Aviva Project area. An additional 48 families, 123 genera and 261 taxa were found in the
southern section of the Lake Logue Nature Reserve and near Lake Indoon. The dominant families in the
Aviva Project area were Myrtaceae (106 taxa), Proteaceae (96 taxa), Papilionaceae (51 taxa) and
Haemodoraceae (31 taxa). The range of taxa recorded reflects the diversity of flora species in the
Eneabba area.
None of the introduced taxa are listed by the Department of Agriculture and Food as Declared Pests
pursuant to Section 37 of the Agriculture and Related Resources Protection Act 1976 [WA].
Previous records from Department of Environment and Conservation databases indicate that there are
potentially twelve Rare, four Priority 1, sixteen Priority 2, thirty eight Priority 3 taxa and seventeen
Priority 4 contained in the local area. Of these database records, seven are listed as Endangered and,
four Vulnerable under the EPBC Act 1999. Mattiske Consulting Pty Ltd fieldwork recorded, two
Declared Rare, one Priority 1, ten Priority 2, 13 Priority 3 and seven Priority 4 of these taxa. Seven
taxa, consisting of one Priority 1, five Priority 2 and one Priority 3 taxa were not previously recorded in
the. In addition to these records, one Priority 1, two Priority 2, three Priority 3 and two Priority 4 taxa
were found in Lake Logue reserve.
A total of one Declared Rare, seven Priority 2, ten Priority 3, and seven Priority 4 taxa will be directly
impacted.
If proposed infrastructure corridor was to go ahead as is, Tetratheca nephelioides, will be significantly
affected at a taxon level. It has been proposed that the corridor is moved to farmland south of the
population, and from a species-conservation point of view, this should be the preferred option. The next
option would be to locate the proposed infrastructure facilities south of the track and north of the
fenceline to minimize the impact on the conservation areas. State Ministerial approval will be required
to take this species if the current route is used.
The status and position of some of the Declared Rare Eucalypt species will have to be confirmed, and if
necessary Federal Approval sought, and relevant protection from indirect impacts given. Many of the
records summarized on the Figures rely on older records and therefore are less reliable in terms of
location accuracy.
All Priority taxa have uncertain status in terms of plant numbers and therefore should be avoided if
possible. However, the known locations and distribution of some taxa may be more affected than others
may by both the proposed projects. These taxa fall into three categories; taxa that are at their northern
extent, taxa that are at their southern extent, or taxa that are locally uncommon.
The taxa Schoenus griffinianus (P3), Lepidobolus quadratus ms (P3), Banksia chamaephyton (P4),
Grevillea rudis (P4) are all at their northern extent in the Coolimba Power Station Project and the
Central West Coal Project. Removal of these populations without some mitigation can reduce the
genetic diversity and therefore the ability of the taxa as a whole to withstand disturbances. If these
species can not be avoided, measures to protect the species genetic diversity will be required (either
ensure seed/specimens of local provenance can be incorporated successfully into rehabilitation, or
establishment of the status or these taxa, including conservation estate offset of found populations).
The taxa at their southern extent include Calytrix purpurea (P2), also a range extension of 70 km south,
Hemiandra sp. Eneabba (H. Demarz 3687) (P3), and , Stylidium aeonioides (P4). The recording of
Calytrix purpurea (P3), represents a population outlier of 70 km. These locations will have to be
avoided until the status of the taxon in the local area can be confirmed. The other taxa at their southern
extent will be exposed to the same risks as taxa at their northern extents and so will require mitigating
measures of some kind.
19.
URS0808/195/08
M
ATTISKE
C
ONSULTING
P
TY
L
TD
The taxa that are locally uncommon include Acacia flabellifolia (P3), Calytrix eneabbensis (P4), and
Verticordia aurea (P4). Some taxa are at more risk than others from the direct impact. Taxa such as
Comesperma rhadinocarpum (P2) has a distribution stretching from Geraldton to Perth, therefore the
effect of the population removal will not be as great as Calytrix eneabbensis (P4), and Verticordia
aurea (P4). These taxa are only found in the local area and should be avoided or have appropriate
mitigating measures put in place. The taxon Acacia flabellifolia (P3) has not been found in the Eneabba
area before, although it has been found from Arrino, north of Three Springs to Watheroo. Therefore this
taxon’s location should be avoided.
The differences between the range of Priority flora on the nearby Eneabba Plains and the proposed
mining operational area indicate that there is significant variation in these communities. This variation
may in part reflect also the differences in sampling regimes between the different areas. The latter is not
surprising in view of the different fire regimes and the high diversity of species in the Eneabba area.
Some range extensions did occur. These extensions again reflect the significant variation in flora in the
Eneabba area. Other Rare and Priority flora species also occur outside the direct impact area. These
species maybe exposed to impacts such as Phytophthora Dieback, weeds, inappropriate fire regimes,
emissions and groundwater. For example, Banksia elegans (P4) are highly susceptible to Phytophthora
Dieback and requires some time in between fires to resprout, as to not diminish the lignotuber (Patrick
and Brown 2001). As long as areas outside of the footprint are given protection from indirect impacts
such as Phytophthora Dieback, weeds, inappropriate fire regimes, emissions and groundwater
drawdown, these species should be protected.
Dostları ilə paylaş: |