In the context of reducing emissions from deforestation and forest degradation (REDD) and the international effort to reduce anthropogenic greenhouse gas emissions, a reliable assessment of ...aboveground forest biomass is a major requirement. Especially in tropical forests which store huge amounts of carbon, a precise quantification of aboveground biomass is of high relevance for REDD activities. This study investigates the potential of X- and L-band SAR data to estimate aboveground biomass (AGB) in intact and degraded tropical forests in Central Kalimantan, Borneo, Indonesia. Based on forest inventory data, aboveground biomass was first estimated using LiDAR data. These results were then used to calibrate SAR backscatter images and to upscale the biomass estimates across large areas and ecosystems. This upscaling approach not only provided aboveground biomass estimates over the whole biomass range from woody regrowth to mature pristine forest but also revealed a spatial variation due to varying growth condition within specific forest types. Single and combined frequencies, as well as mono- and multi-temporal TerraSAR-X and ALOS PALSAR biomass estimation models were analyzed for the development of accurate biomass estimations. Regarding the single frequency analysis overall ALOS PALSAR backscatter is more sensitive to AGB than TerraSAR-X, especially in the higher biomass range (>
100
t/ha). However, ALOS PALSAR results were less accurate in low biomass ranges due to a higher variance. The multi-temporal L- and X-band combined model achieved the best result and was therefore tested for its temporal and spatial transferability. The achieved accuracy for this model using nearly 400 independent validation points was
r²
=
0.53 with an
RMSE of 79
t/ha. The model is valid up to 307
t/ha with an accuracy requirement of 50
t/ha and up to 614
t/ha with an accuracy requirement of 100
t/ha in flat terrain. The results demonstrate that direct biomass measurements based on the synergistic use of L- and X-band SAR can provide large-scale AGB estimations for tropical forests. In the context of REDD monitoring the results can be used for the assessment of the spatial distribution of the biomass, also indicating trends in high biomass ranges and the characterization of the spatial patterns in different forest types.
► We analyzed X- and L-band SAR data to estimate tropical forest aboveground biomass. ► Field biomass reference data were upscaled using LiDAR measurements. ► The multi-temporal L- and X-band combined model achieved the best result. ►The model is valid up to 307
t/ha. ►Spatial distribution of AGB is indicated over the whole biomass range up to 614
t/ha.
Large-scale fires occur frequently across Indonesia, particularly in the southern region of Kalimantan and eastern Sumatra. They have considerable impacts on carbon emissions, haze production, ...biodiversity, health, and economic activities. In this study, we demonstrate that severe fire and haze events in Indonesia can generally be predicted months in advance using predictions of seasonal rainfall from the ECMWF System 4 coupled ocean-atmosphere model. Based on analyses of long, up-to-date series observations on burnt area, rainfall, and tree cover, we demonstrate that fire activity is negatively correlated with rainfall and is positively associated with deforestation in Indonesia. There is a contrast between the southern region of Kalimantan (high fire activity, high tree cover loss, and strong non-linear correlation between observed rainfall and fire) and the central region of Kalimantan (low fire activity, low tree cover loss, and weak, non-linear correlation between observed rainfall and fire). The ECMWF seasonal forecast provides skilled forecasts of burnt and fire-affected area with several months lead time explaining at least 70% of the variance between rainfall and burnt and fire-affected area. Results are strongly influenced by El Niño years which show a consistent positive bias. Overall, our findings point to a high potential for using a more physical-based method for predicting fires with several months lead time in the tropics rather than one based on indexes only. We argue that seasonal precipitation forecasts should be central to Indonesia's evolving fire management policy.
In the context of the ongoing climate change discussions the importance of peatlands as carbon stores is increasingly recognised in the public. Drainage, deforestation and peat fires are the main ...reasons for the release of huge amounts of carbon from peatlands. Successful restoration of degraded tropical peatlands is of high interest due to their huge carbon store and sequestration potential. The blocking of drainage canals by dam building has become one of the most important measures to restore the hydrology and the ecological function of the peat domes. This study investigates the capability of using multitemporal radar remote sensing imagery for monitoring the hydrological effects of these measures. The study area is the former Mega Rice Project area in Central Kalimantan, Indonesia, where peat drainage and forest degradation is especially intense. Restoration measures started in July 2004 by building 30 large dams until June 2008. We applied change detection analysis with more than 80 ENVISAT ASAR and ALOS PALSAR images, acquired between 2004 and 2009. Radar signal increases of up to 1.36 dB show that high frequency multitemporal radar satellite imagery can be used to detect an increase in peat soil moisture after dam construction, especially in deforested areas with a high density of dams. Furthermore, a strong correlation between cross-polarised radar backscatter coefficients and groundwater levels above −50 cm was found. Monitoring peatland rewetting and quantifying groundwater level variations is important information for vegetation re-establishment, fire hazard warning and making carbon emission mitigation tradable under the voluntary carbon market or REDD (Reducing Emissions from Deforestation and Degradation) mechanism.
Climate change mitigation mechanisms, such as REDD+, which aim at avoiding deforestation and forest degradation, require an accurate aboveground biomass (AGB) monitoring. In the present study, ...multi-temporal X-(TerraSAR-X) and L-band (ALOS PALSAR) SAR data and a multispectral RapidEye image were analyzed for their ability to estimate AGB in a tropical forested peatland area in Central Kalimantan on Borneo, Indonesia. Field inventory AGB data was used to calibrate regression models based on SAR backscatter values and spectral unmixed fractions of the RapidEye image. The independent validation indicated that the estimated AGB using optical data is more accurate (RMSE=44%) than the SAR estimated AGB (RMSE=82%). AGB derived from RapidEye data overestimates AGB on burned areas, but these estimations depict degradation through low impact selective logging. The SAR model estimated AGB accurately in lower biomass ranges and on burned scars.
Why, in April 1969, did ADORNO, the philosopher of the student revolt, the advocate of the avant-garde from Schoenberg to Beckett, flee when he was faced with the performative actions of protesting ...students with naked breasts? The article discusses connections between ADORNO’S Dialectics of Enlightenment, Negative Dialectics and Aesthetic Theory and the aesthetics of today’s performative and post-dramatic theatre. For ADORNO, theatre remained a place of art, and the revolution did not come to fruition in the per-formative denial of meaning, in the cruel reality of “sirens”, and in deconstruction, but in the work of art itself, that is supposed to represent the irreconcilable and thus to lead to reconciliation.
Vast and disastrous fires occurred on Borneo during the 2015 dry season, pushing Indonesia into the top five carbon emitting countries. The region was affected by a very strong El Niño-Southern ...Oscillation (ENSO) climate phenomenon, on par with the last severe event in 1997/98. Fire dynamics in Central Kalimantan were investigated using an innovative sensor offering higher sensitivity to a wider range of fire intensities at a finer spatial resolution (160 m) than heretofore available. The sensor is onboard the TET-1 satellite, part of the German Aerospace Center (DLR) FireBird mission. TET-1 images (acquired every 2-3 days) from the middle infrared were used to detect fires continuously burning for almost three weeks in the protected peatlands of Sebangau National Park as well as surrounding areas with active logging and oil palm concessions. TET-1 detection capabilities were compared with MODIS active fire detection and Landsat burned area algorithms. Fire dynamics, including fire front propagation speed and area burned, were investigated. We show that TET-1 has improved detection capabilities over MODIS in monitoring low-intensity peatland fire fronts through thick smoke and haze. Analysis of fire dynamics revealed that the largest burned areas resulted from fire front lines started from multiple locations, and the highest propagation speeds were in excess of 500 m/day (all over peat > 2m deep). Fires were found to occur most often in concessions that contained drainage infrastructure but were not cleared prior to the fire season. Benefits of implementing this sensor system to improve current fire management techniques are discussed. Near real-time fire detection together with enhanced fire behavior monitoring capabilities would not only improve firefighting efforts, but also benefit analysis of fire impact on tropical peatlands, greenhouse gas emission estimations as well as mitigation measures to reduce severe fire events in the future.
Das Drama ist eine der relevantesten Strukturen in einer sich globalisierenden und transmedial erweiternden Kultur. In seiner historischen Konstanz wie Wandlungsfahigkeit - vom Dionysostheater bis ...zur aktuellen Qualitatsserie - bleibt es, trotz performativer Asthetiken, hochst aktuell.Die Publikation bietet eine umfassende historische wie systematische Darstellung aus literatur- und theaterwissenschaftlicher Perspektive. Ein besonderes Augenmerk wird auf die Verbindung zwischen informierendem Uberblick und Ausdifferenzierungen wie Transformationen des Dramas gelegt. Berucksichtigt wird die Integration des Dramas in theatrale Institutionen und deren Produktionsprozesse, ebenso asthetische Distanzierungen bzw. mediale Reflexionen oder Dekonstruktionen. Neben verschiedenen Dramaturgien und Kontexten wie Politik, Wirtschaft, Zensur, Didaktik oder Psychologie werden postdramatische und auereuropaische Formen behandelt, zudem transdisziplinare Bezuge zu neueren Medien wie Film, TV-Serie, Computerspiel, Musiktheater und Tanz hergestellt.Dem Band gelingt ein kompakter Uberblick, der dem Drama in seiner systematischen wie historischen Komplexitat gerecht wird.
Pollen tubes are among the fastest tip-growing plant cells and represent an excellent experimental system for studying the dynamics and spatiotemporal control of polarized cell growth. However, ...investigating pollen tube tip growth in the model plant Arabidopsis remains difficult because in vitro pollen germination and pollen tube growth rates are highly variable and largely different from those observed in pistils, most likely due to growth-promoting properties of the female reproductive tract. We found that in vitro grown Arabidopsis pollen respond to brassinosteroid (BR) in a dose-dependent manner. Pollen germination and pollen tube growth increased nine- and fivefold, respectively, when media were supplemented with 10 µM epibrassinolide (epiBL), resulting in growth kinetics more similar to growth in vivo. Expression analyses show that the promoter of one of the key enzymes in BR biosynthesis,
CYP90A1/CPD,
is highly active in the cells of the reproductive tract that form the pathway for pollen tubes from the stigma to the ovules. Pollen tubes grew significantly shorter through the reproductive tract of a
cyp90a1
mutant compared to the wild type, or to a BR perception mutant. Our results show that epiBL promotes pollen germination and tube growth in vitro and suggest that the cells of the reproductive tract provide BR compounds to stimulate pollen tube growth.
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