Mapping peatlands, peatland carbon and tl d b d climate change - PowerPoint PPT Presentation

Mapping peatlands, peatland carbon and tl d b d climate change impacts climate change impacts S. J. Chapman

I t Introduction d ti • Context of climate change • Peatlands form a significant carbon store P l d f i ifi b • They may be an active sink (or source) y y ( ) • Role threatened by land use change, climate change atmospheric inp ts change, atmospheric inputs • Each country needs to assess its C stock

B Basin peat i t

Bl Blanket peat k t t

Calculation of total carbon stock Total carbon stock = area  depth  dry bulk density  %C But exist uncertainties in each But exist uncertainties in each

The Peatlands of Scotland England Scotland, England and Wales

Area • Error on area not easy to define Area (kha) Area (kha) 1111 ± 26 Blanket peat p 73 ± 1 Basin peat 542 ± 36 542 ± 36 Semi-confined peat Semi confined peat 1727 ± 45 Peatland total

S Survey kit kit D Depthing Rods hi R d Russian (or Macaulay) Sampler Russian (or Macaulay) Sampler

A hi Archived records d d

Areas Areas sampled for depth

Depth Depth Peat depth (m) p ( ) Peat Type Basin peat (>0.5 m) Undifferentiated blanket peat (>0.5 m) p ( ) Eroded basin peat (>0.5 m) Deep blanket peat (>1 m) Eroded deep blanket peat (>1 m) Eroded undifferentiated blanket peat (>0.5 m) Peat in other map Blanket peat units Basin peat S Semi-confined peat i fi d t

Depth Depth Peat depth (m) p ( ) means ± standard errors (number of values) Peat Type Weighted Average Depth Depth 2.87 ± 0.09 (360) Basin peat (>0.5 m) 1.34 ± 0.10 (652) Undifferentiated blanket peat (>0.5 m) p ( ) ( ) 2.72 ± 0.39 (4) Eroded basin peat (>0.5 m) 2.30 ± 0.15 (166) Deep blanket peat (>1 m) 1.70 ± 0.04 (30) Eroded deep blanket peat (>1 m) 1.32 ± 0.08 (116) Eroded undifferentiated blanket peat (>0.5 m) 1.12 ± 0.07 (48) Peat in other map Blanket peat units 2.87 ± 0.34 (8) Basin peat 1 28 ± 0 09 (71) 1.28 ± 0.09 (71) S Semi-confined peat i fi d t

Peat depth in depth in Scotland Scotland

D Dry Bulk density B lk d it • F Few values l • Not easy to measure Bulk density (g cm ‐ 3 ) means ± standard errors (number of values) Depth (m) 0–0.3 0.3–1 > 1 Basin 0.136 ± 0.022 (12) 0.114 ± 0.017 (17) 0.092 ± 0.004 (16) peat Blanket 0.134 ± 0.009 (17) 0.123 ± 0.004 (34) 0.143 ± 0.010 (8) peat

P Proportion of carbon ti f b • Fairly well defined y Carbon contents (%) means ± standard errors (number of values) Depth (m) 0–0.3 0.3–1 > 1 51.1 ± 1.0 (25) 48.6 ± 1.1 (43) 60.8 ± 3.4 (2) Basin peat 50 6 ± 1 8 (21) 50.6 ± 1.8 (21) 52 9 ± 0 7 (49) 52.9 ± 0.7 (49) 54 6 ± 3 2 (7) 54.6 ± 3.2 (7) Blanket peat Blanket peat Eroded deep 50.1 ± 3.5 (10) 57.1 ± 0.4 (8) 54.2 ± 1.2 (2) blanket peat 53.0 ± 0.9 (40) 55.2 ± 1.0 (33) 54.0 ± 3.2 (9) Eroded blanket peat

R l ti Relative uncertainties t i ti Estimation of errors Estimation of errors % Error in Parameter No. samples Location estimates Country-wide but some areas under- Depth ~6000 7.2 represented Country-wide but mainly surface C t id b t i l f % C 240 3.4 (0 – 1 m) Country-wide but weighted towards NE Bulk density Bulk density 104 104 8 3 8.3 Scotland and few deep samples Scotland and few deep samples (>2 m) Area 1455 polygons Country-wide yg y 4.5

Carbon stock Carbon stock Estimated carbon stocks (MtC) within Scotland for soils with an organic surface horizon (means ± SE) Soil type C Stock (<100 (<100 cm depth) Blanket peat Bl k t t 737 ± 19 Basin peat 44 ± 4 Semi-confined peat 323 ± 39 Total peat p 1104 ± 44 1104 ± 44

Carbon stock Carbon stock Estimated carbon stocks (MtC) within Scotland for soils with an organic surface horizon (means ± SE) Soil type C Stock C Stock (<100 (<100 cm (>100 (>100 cm depth) depth) Blanket peat Bl k t t 737 ± 19 355 ± 46 Basin peat 44 ± 4 77 ± 6 Semi-confined peat 323 ± 39 85 ± 28 Total peat p 1104 ± 44 1104 ± 44 516 ± 55 516 ± 55

Carbon stock Carbon stock Estimated carbon stocks (MtC) within Scotland for soils with an organic surface horizon (means ± SE) Soil type C Stock C Stock Total C (<100 (<100 cm (>100 (>100 cm St Stock k depth) depth) Blanket peat Bl k t t 737 ± 19 355 ± 46 1091 ± 50 Basin peat 44 ± 4 77 ± 6 120 ± 8 Semi-confined peat 323 ± 39 85 ± 28 408 ± 49 Total peat p 1104 ± 44 1104 ± 44 516 ± 55 516 ± 55 1620 ± 70 1620 ± 70

Peatland eat a d Carbon density in S Scotland tl d Chapman, S.J., Bell, J., Donnelly, D., Lilly, A., 2009. Carbon stocks in Scottish peatlands. Soil Use and Management 25, 105 ‐ 112.

NSIS points (10 km spacing)

NSIS NSIS • National Soils Inventory for Scotland (NSIS_1) • Select points where peat occurs • Total peatland C stock (to 100 cm) 1166 Mt C • Compares with 1104 Mt C using map units

C Conclusions l i • We believe we have a better estimate • Some areas of Scotland are still uncertain Some areas of Scotland are still uncertain • We still need better bulk density values • Peatland C stock is 56% of total soil C stock Peatland C stock is 56% of total soil C stock

Projected changes in bioclimatic space associated with the 1961 ‐ 90 h h baseline climate and mapped area of blanket peat using i UKCIP02 high and low emissions scenarios. i Bioclimatic envelope models used were P50, Clark, J., Gallego ‐ Sala, A., P65 PT LM H P65 ‐ PT, LM, H ‐ V, Allott, T., Chapman, S., V All tt T Ch S Farewell, T., Freeman, C., GLM, BBOG, House, J., I, Orr, H., BBOG ‐ TREE, Prentice, I., Smith, P., 2010. Assessing the BBOG ‐ GLM, vulnerability of blanket BBOG GAM BBOG ‐ GAM peat to climate change using an ensemble of statistical bioclimatic envelope models. Climate Research 45, 131 ‐ U462.

Area covered by the by the bioclimatic envelope of blanket peatlands peatlands predicted by PeatStash using the bioclimatic bioclimatic thresholds associated with the 1961 ‐ 90 baseline 90 baseline climate for the UKCIP02 high and low Gallego ‐ Sala, A.V., emissions emissions Clark, J.M., House, J.I., scenarios for Orr, H.G., Prentice, I., Smith, P., Farewell, T., three time Chapman, S.J., 2010. periods: 2020s, Bioclimatic envelope 2050s and 2050s and model of climate f change impacts on 2080s. blanket peatland distribution in Great Britain. Climate Research 45, 151 ‐ 162.

Northern temperate and tropical peats do differ! FTIR spectra 3.5 Scottish 3 Malaysian 2 5 2.5 2 1.5 1 0.5 0 0 3300 2300 1300 300