Monitoring Peatland Degradation and Recovery Using Satellite Radar. Case Study: Irish Midlands

Overview Map (Sentinel-1)• Differential interferometric synthetic aperture radar

(DInSAR) satellite remote sensing techniques have been used for many years to measure land surface motion.

• One major restriction is that they generally do not work so well over vegetated areas.

• We have solved that problem by developing the ISBAS technique which can survey all terrains.

• Overcoming this restriction has opened up the possibility of monitoring Peatland continuously over large areas with DInSAR.

• To illustrate the potential we have surveyed all peat bogs within a large area in the Irish Midlands

• Using recent Sentinel-1 data and archive ENVISAT data we compare surface motion during the periods 2015-2016 to 2002-2009.

• Three lowland raised bogs within the area illustrate the potential of this technique.

D. Large1; D. Gee²; A. Sowter²; A. Novellino²; P. Bhatia21University of Nottingham, UK; 2Geomatic Ventures Limited, UK

Key Observations

Clara Bog – Peatland Collapse

1991-20023

• Intensifying subsidence reported3 from W Clara Bog 1991 – 2002 as a result of drainage into underlying aquifer.

2002-2009 • Slow sustained subsidence, most

notable in W Clara Bog2014-15 • Well defined area of rapid subsidence

in W Clara Bog focussed on the Western soakaway

• Stabilisation and uplift in the central Clara Bog.

• Patterns of surface motion appear to be strongly linked to drainage.

Application:• Could be used to revise restoration

potential and strategy

Abbeyleix Bog – Response to Drain Blocking

Key Observations

Late 1980s• Drainage ditches created

2009• Drainage ditches blocked

2002 – 2009 • Peat surface subsiding. maximum

rate SW of disused railway line.

2014-15 • Rapid uplift of the peat surface along

a N-S line, just W of the disused railway line.

Issues to be addressed: • Link between mechanical, response,

gas flux, cause of uplift and the integrity of the peat structure

Knockahaw Bog – Uplift of a Degraded Raised BogKey ObservationsLate 1980s• Drainage ditches created4

2002-2009• S and E subsiding. NW stable2013• Bord na Mona note “no infilling of

drains with the exception of a couple of drains that had begun to become infilled around and within the flushes and in the NW section”. 4

2014-15 • Rapid uplift of the peat surface in NW

of bog and upstream of flushes. • Minimal changes to drainage appear

to have had a major influence on water retention and uplift.

Legend

Abstract Area of Interest

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References and acknowledgements:1. Drainage for Clara acknowledges LIFE14NATIE000032.2. Drainage provide by Bord na Mona3. Heggler et al 2005, Subsidence of Clara Bog West...

Rapport 121 Wageningen University4. Knockahaw rehabilitation plan, Bord na Mona