Wambo Coal AEMR 2011-2012 - Peabody Energy

2011-2012 AEMR
representative pasture rehabilitation locations.
During 2010 six new transects were established,
comprising:
Two pasture analogue transects;
Two woodland analogue transects; and
Two pasture rehabilitation transects.
The total number of EFA transects investigated
during 2011 was 20 and comprised:
Three analogue woodland transects;
Four rehabilitation woodland transects;
Three analogue pasture transects; and
Ten rehabilitation pasture transects.
With the exception of one transect (9R) all other
pasture rehabilitation transects recorded LFA scores
similar to the analogue transects in 2011. This
suggests that at least during 2011 that many of the
rehabilitation transects had a similar landscape
function to the target analogue transects. Continued
sampling will be required to determine whether the
rehabilitation analogue sites will continue to exhibit
such high scores during future years particularly
those of harsher conditions. Only when
rehabilitation sites recorded similar or better LFA
scores than analogues sites over a range of years
and seasonal conditions, can the rehabilitation
works be considered a success from an EFA
assessment.
Woodland rehabilitation transects appear to be
trending towards the analogue values.
Landscape Organisational Index (LOI) and Stability
Index (SI) scores at the analogue transects were
approximately consistent with the rehabilitation
transect scores, however, some rehabilitation sites
had lower infiltration index (INFI) and nutrient index
(NI) scores than analogue transects. Overall EFA
analysis indicates that the woodland rehabilitation
transects within the open cut area of Wambo Coal
are approaching but have not yet demonstrated LFA
values characteristic of target woodland
communities. However the general pattern of
increase in EFA parameters suggests that the
rehabilitation woodland transects are improving
towards the analogue goal.
NWCD Stage 2 EFA
RPS was engaged by Wambo Coal Pty Ltd (Wambo
Coal) to undertake the November 2011 Ecosystem
Function Analysis (EFA) monitoring of 14 previously
established riparian EFA transects. This is the fourth
year of monitoring of rehabilitation works along the
North Wambo Creek Diversion (NWCD). The EFA
monitoring of 10 rehabilitation transects began in
the October 2008. Two further transects (one
analogue and one rehab) were previously
established in 2006 as part of previous EFA
monitoring of open cut rehabilitation transects. In
2010, two new analogue sites were established
along North Wambo Creek to bring the total number
of analogue sites to three (as recommended in the
2009 report). Also in 2010, rehabilitation transect
14R was moved to a more suitable location, as
recommended in the 2009 report.
LFA scores were relatively constant in 2011 in
comparison to previous years. Similarity in scores
was likely due to the continued presence of the tall
grassland along NWCD that was also present in
2009 and 2010. The reasons for declines in some
LFA scores were not known, however the data
indicates that it is related to a decline in the ability of
water to infiltrate the soil and a reduced level of
nutrient cycling via litter decomposition.
Along the approximate 2.5 km length (straight line)
of the NWCD there was a general pattern of
declining LFA scores from upstream to downstream.
As the good season for grass growth was common
to all NWCD transects, the reason for the
geographic variation in scores was unknown.
Vegetation dynamics and habitat complexity scores
were approximately similar between 2009, 2010 and
2011.
Open Cut EFA Transect Locations
NWCD Stage 2 EFA Transect Locations
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