Wambo Coal AEMR 2010-2011 - Peabody Energy

2010-2011 AEMRtransects had a similar landscape function to thetarget analogue transects. Continued sampling willbe required to determine whether the rehabilitationanalogue sites will continue to exhibit such highscores during future years, particularly those ofharsher climatic conditions. Only when rehabilitationsites record similar or better LFA scores thananalogues sites, over a range of years and seasonalconditions, can the rehabilitation works beconsidered a success.or other soil characteristics that may vary along thelength of the NWCD.Vegetation dynamics and habitat complexity scoreswere approximately similar between 2009 and 2010.Recommendations have been made to improve theinterpretability of data collected on disturbancefactors present during sampling.Woodland rehabilitation transects appear to betrending towards the analogue values. Scores at theanalogue transects were approximately consistentwith the rehabilitation transect scores however, allother LFA components were lower at rehabilitationthan analogue transects. Overall LFA analysisindicates that the woodland rehabilitation transectsare approaching, but have not yet demonstrated,LFA values characteristic of target woodlandcommunities. However, the general pattern ofincrease in LFA parameters suggests that therehabilitation woodland transects are improvingtowards the analogue goal.Riparian EFARPS was engaged by WCPL to undertake the 2010EFA monitoring of 12 previously established riparianEFA transects. This report presents the results ofthe third year of monitoring of rehabilitation worksalong the North Wambo Creek Diversion (NWCD).The NWCD was completed in August 2008 and EFAmonitoring of 10 rehabilitation transects began inthe October 2008 (ENSR, 2009). Two furthertransects (one analogue and one rehab) werepreviously established in 2006 as part of previousEFA monitoring of open cut rehabilitation transects(HLA, 2006).In 2010, two new analogue sites were establishedalong North Wambo Creek to bring the total numberof analogue sites to three (as recommended in the2009 report). Also in 2010, rehabilitation transect14R was moved to a more suitable location, asrecommended in the 2009 report.LFA scores were either relatively constant ordeclined slightly in 2010. Similarity in scores waslikely due to the continued presence of the tallgrassland along NWCD. The reasons for declines insome LFA scores were unknown but were related toa declining ability of water to infiltrate the soil and areduced level of nutrient cycling via litterdecomposition. These scores will be continued tobe monitored closely to identify possible causes infutures years.Along the approximate 2.5 km length (straight line)of the NWCD there was a general pattern ofdeclining LFA scores from upstream to downstream.As the good season for grass growth was commonto all NWCD transects, the reason for thegeographic variation in scores was unknown butmay be related to differences in soil type, soil depthPage 87