Difficulties Encountered in Estimating Soil Emissions due to LUCF Gary W. Theseira Forest Research Institute Malaysia Kuala Lumpur, Malaysia

Tropical Soils: Tropical climates –High year-round temperatures –High rainfall –High biomass production –High decomposition rates Tropical soils are: –Highly weathered –Low in organic matter –Not normally considered a significant sink for carbon There are, however notable exceptions …

Soils with significant Organic Carbon content: Peat swamps (Histosols) –Accumulation of organic matter under fresh-water swamps or soils with a water table close to the soil surface Bris Soils (Spodosols) –Accumulation of organic matter due to the presence of a fluctuating water table within a deep, sandy soil Highland organic soils (Histosols) –Accumulation of organic matter above the soil surface due to low night temperatures that reduce decomposition rates.

Extent of Peat Swamps in Malaysia Peninsular Malaysia 793,000 ha Sarawak1,466,000 ha Sabah 86,000 ha Total of ca. 2.5 million ha Comprise 7% of the total land area

Properties of Peat Swamps in Malaysia Developed during comparatively recent times –Carbon dated ca y.b.p. Formed under poorly drained terrestrial conditions rather than a permanent water body Profile –Upper layer20 to 30cm thicksapric o.m. –Middle layer30 to 40cm thickhemic o.m. –Bottom layervariable thicknessfabric o.m. Overall depth of the peat may reach 17m (Anderson, 1983)

Utilization Status of Peat Swamps in Malaysia Primary use still peat swamp forest Little more than 10% converted for agriculture, however … Some located within regional agricultural development schemes –Johor Barat –Endau-Rompin > 50% of project area located on peat soils Located primarily in Peninsular Malaysia

Sources of Uncertainty in Utilization Status of Peat Swamps in Malaysia How do we estimate land area under different and changing use: Steady-state single-use –Non-utilized negligible emissions or net sink –Low-impact uselow emissions –Intensive usehigh emissions Land in transition/multiple-use –Gradual change & small land parcels –Catastrophic change INTENSIVE/EXTENSIVE DRAINAGE PEAT FIRES Illegal or unreported land use change

Sources of Uncertainty of Emissions from Peat Swamps How do we estimate emissions from peat soils associated with: Logging –Selective logging –Clearcut logging Agriculture –Subsistence –Commercial vegetable and fruit production –Oil palm production Other –Fishing –Fish farming –Fuelwood collection

Drainage and Subsidence Measured subsidence data for Sarawak SourceSubsidence (cm/year) Initial year 1 and 2 (consolidation) After year 2 (oxidation & shrinkage) Tie and Kueh (1979)506 Yogeswaran (1990)16 Agric. Research Station Sibu 4.4a Salmah (1998)5 Chin and Poo (1991)6 – 35b a. Average subsidence rate over the period 1983 – 2000 b. Higher values in the vicinity of the drains (Source: PS Konsultant and LAWOO, 2001)

Complementary Verification Technologies Modelling techniques for estimating oxidization rates given different rates of water-table recession Ground-penetrating radar to estimate water table depth and overall peat thickness Use GIS/thermal imaging to characterize peat swamps –Hotpeat fires –Warmdry edge –Ambientpeat swamp –Coolsurface water

Solving Administrative and Communication Issues between Government Ministries Consolidating Natural Resource and Environmental agencies under a common ministry Mandate from the Prime Minister to Improve Communication and Strengthen Cooperative Ties between Environmental, Industrial, Technological and Economic Planning ministries

International Cooperation Easier said than done Always torn between ‘bottom-up’ and ‘top-down’ Subject to Bureaucratic Inertia Optimistic ‘Small steps & Slow gains’ approach Persistent