CREACIÓN DE VENTANAS

This thesis is structured in seven sections (CHAPTER I-VII). In Chapter I a short introduction to Indonesian peatlands, the environmental problems surrounding these ecosystems, possible mechanisms in protecting their ecosystems services, an overview of the used remote sensing sensors, the main goal, the specific objectives, and the structure of the thesis are given. CHAPTER II-VI are the main sections and relate to the specific objectives outlined above. In CHAPTER II, using an airborne LIDAR data set acquired in Central Kalimantan, in 2007, one year after the severe peatland fires of 2006, the average peat burn scar depth was determined. Based on this result and the burned area determined from Landsat imagery the emitted carbon, within a 2.79 million hectare study area, was estimated. Further the approximate carbon emissions through peatland fires for Indonesia in 2006 based on active fire recording of the MODIS, a correction factor for the MODIS burned area determined from a correlation with Landsat-derived burned areas, peatland maps of Indonesia, and the derived peat burn depth were calculated. In CHAPTER III, based on the same airborne LiDAR set analyzed in CHAPTER II, peat loss not only after single but also multiple fire events were calculated through 3D modelling of a pre-fire peat surface. These peat loss calculations were then set in relation to water table measurements, burn frequency, the year of the fire occurrence, and the duration of the dry season to assess the influence of these factors. Additionally based on object oriented fire scar classifications (derived from Landsat data) between the years 1990- 2009 and the calculated peat loss the carbon emitted within the Kapuas district (1,489,325ha; Central Kalimantan) was estimated. In CHAPTER IV the applicability of quality filtered ICESat/GLAS data to measure peatland topography as a proxy for peat volume and to estimate peat swamp forest AGB in a thoroughly investigated study site in Central Kalimantan was assessed. Mean SRTM elevation and three 3D peatland elevation models derived from SRTM data were correlated to the corresponding ICESat/GLAS elevation. Based on the correlation of in-situ peat swamp forest AGB and airborne LiDAR data an ICESat/GLAS AGB prediction model was developed. In CHAPTER V the applicability of airborne LiDAR data, based on the same airborne LiDAR set analyzed in CHAPTER II, to estimate AGB of two different tropical rainforest types (lowland dipterocarp and peat swamp forest) in Central Kalimantan was tested by developing multiple regression models at plot

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level. In order to sample a high number of field plots the angle count method was applied which allows fast sampling and more laborious fixed-area plots (three nests of circular shape) were used as a control. AGB-prediction models were established for each forest type using statistical values of the LiDAR point clouds and the forest inventory plots. These regression models were then applied to six LiDAR tracks (altogether with a size of 5,241ha) covering unlogged, logged and burned lowland dipterocarp and peat swamp forest. In CHAPTER VI AGB was estimated for different tropical forests (lowland dipterocarp and peat swamp forest) in Central Kalimantan through correlating airborne LiDAR data (the same airborne LiDAR set analyzed in CHAPTER II) to forest inventory data. Two metrics, the Quadratic Mean Canopy profile Height (QMCH) and the Centroid Height (CH), derived from the LiDAR height histograms were correlated to AGB values from a forest inventory. A possible improvement of the regression models through the use of the LiDAR point densities as weight was tested. A rigorous covariance propagation analysis was carried out to find the LiDAR point density with the best cost-benefit relation. Further a Landsat based classification approach, in which each land cover class was linked to a single biomass value determined from a regional biomass database, was compared to LiDAR derived AGB estimates. Finally, CHAPTER VII synthesizes the six preceding sections and provides directions for future research.

CHAPTERS II-VI were written as stand-alone manuscripts to be published in international peer-reviewed journals. Each chapter is therefore structured into subsections introduction, materials and methods, results, discussion and conclusions, thereby resulting in a limited amount of recurring material:

CHAPTER II: Ballhorn U, Siegert F, Mason M, Limin S (2009) Derivation of burn scar depths and estimation of carbon emissions with LiDAR in Indonesian peatlands. Proceedings of the National Academy of Sciences of the United States of America, 106, 21213-21218. CHAPTER III: Ballhorn U, Jubanski J, Siegert F Pre-fire surface 3D modeling of

tropical peatland burn scars based on airborne LiDAR in Central Kalimantan, Indonesia. Manuscript in preparation for Global Change Biology.

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CHAPTER IV: Ballhorn U, Jubanski J, Siegert F (2011) ICESat/GLAS Data as a Measurement Tool for Peatland Topography and Peat Swamp Forest Biomass in Kalimantan, Indonesia. Remote Sensing, 3, 1957-1982.

CHAPTER V: Kronseder K, Ballhorn U, Böhm V, Siegert F Above ground biomass estimation across forest types at different degradation levels in Central Kalimantan using LiDAR data. International Journal of Applied Earth Observations and Geoinformation, in print.

CHAPTER VI: Jubanski J, Ballhorn U, Kronseder K, Siegert F Deriving forest above ground biomass in Central Kalimantan (Indonesia) using airborne LiDAR data. Manuscript in preparation for Nature Climate Change.

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CHAPTER II: