Peat Forest Research Articles

A mathematical optimisation model for analysis of minimal cropland expansion in agro value chains

Increasing population, accelerated urbanisation and rise in income generation have led to the increased concern on sustainable production and consumption of food. This has put severe stress on farmers and plantation owners to rapid expansion of crop lands and plantations to meet the demand. However, the expansion has resulted in large scale unplanned deforestation. The proposed work presents a Mixed Integer Linear Programming (MILP) model to strategies for minimal crop land and plantation expansion based on the predicted future demand of agro-products. The proposed model is based on the concept which used previously to strategies operation of utility systems. In this work, the proposed model is used to determine the minimal lands for expansion (if required) when there is an increased demand. However, if the demand of the agro-product is projected to decrease, then the model identifies the optimised excess existing crop land(s) or plantation(s) that can be removed from the value chain. Based on the optimised result, the cost involved in expansion (i.e., deforestation and planting costs, etc.) and the transport cost can be determined. The selection of truck capacity for the optimised logistics of the agro products from the cropland to the processing facility can also be determined. By minimising the total cost (expansion cost and transport cost), the area of expansion and transportation distance can be minimised to meet the increased demand requirement, thereby resulting in lesser environmental impact. Note that, the model provides strategic optimisation for expansion of croplands and tactical optimisation for the logistics between crop lands and processing facility. A palm oil value chain is solved in this work to illustrate the proposed model. Five different scenarios with increasing and decreasing palm oil demands were solved and their respective results are discussed. The scenarios analyse the expansion in different types of lands — grasslands, tropical forests and peat forests. It is noted that the model selected grasslands over the other land types due to their least expansion cost and Land Use Change (LUC) tax rates; showing that the proposed approach promotes sustainability through cost. At higher palm oil demands scenario, apart from grasslands, tropical or peat forest lands are also seletected for expansion. Sensitivity analysis of increasing palm oil demand on expansion cost and LUC tax rates on total cost is also presented.

Estimation of Indonesian Peat Forest Carbon Emissions based on Soil Moisture Active Passive (SMAP) Satellite Image

Calculation of carbon emission in tropical peatland forest still unsolved problem. In this paper, we propose a method to calculate carbon emission by using Soil Moisture Active Passive (SMAP) satellite. The SMAP images on January 2018 enhanced 1.3 radiometer Global Daily 9 km, EASE grid overlayed with peat map. The water table mapping obtained by using empirical relation between soil moisture and water table in January 2018 shows a pattern according to some observation. The carbon emission map on January 2018 shows the average is about 280 gC km-2.

Estimation of Peat Surface Carbon Stocks on The Semenanjung Kampar from Land Use Changes Using Landsat Multi-Temporal in 2009-2018

Remote sensing has advantages in terms of temporal resolution that can be used to check changes in an object at different times. The Semenanjung Kampar peatland underwent land use change after the change in PP No. 71 of 2014 became PP No. 57 of 2016 which requires companies (paper companies) to restore the ecosystem on the Semenanjung Kampar. These changes were analyzed by utilizing remote sensing technology through multi-temporal imagery.This study aims to analyze changes in peatland use on the Semenanjung Kampar in 2009, 2013 and 2018, then estimate carbon stocks from changes in peatland use. The method used is the classification of Iso Cluster unsupervised and calculation of increase and decrease in carbon stocks (Gain and Loss). Based on this research the results of the accuracy of the classification of changes in land use on the Semenanjung Kampar were 0.72 or 72%.Changes in land use on the Semenanjung Kampar occur dynamically.The dominant land change for the 2009-2013 period was shrubs which became acacia forests 89386.31 ha and bushes from 2013-2018 to oil palm plantations 57878.47 ha. Furthermore, carbon stocks in the period 2009-2013 that have increased (acces) are 8.2% acacia forest and 13% decrease in primary peat forest while the 2013-2018 period has increased, namely 8% oil palm plantation and 21% shrub decline.

The exchange of water and energy between a tropical peat forest and the atmosphere: Seasonal trends and comparison against other tropical rainforests

Tropical rainforests control the exchange of water and energy between the land surface and the atmosphere near the equator and thus play an important role in the global climate system. Measurements of latent (LE) and sensible heat exchange (H) have not been synthesized across global tropical rainforests to date, which can help place observations from individual tropical forests in a global context. We measured LE and H for four years in a tropical peat forest ecosystem in Sarawak, Malaysian Borneo using eddy covariance, and hypothesize that the study ecosystem will exhibit less seasonal variability in turbulent fluxes than other tropical ecosystems as soil water is not expected to be limiting in a tropical forested wetland. LE and H show little variability across seasons in the study ecosystem, with LE values on the order of 11 MJ m−2 day and H on the order of 3 MJ m−2 day−1. Annual evapotranspiration (ET) did not differ among years and averaged 1579 ± 47 mm year−1. LE exceeded characteristic values from other tropical rainforest ecosystems in the FLUXNET2015 database with the exception of GF-Guy near coastal French Guyana, which averaged 8–11 MJ m−2 day−1. The Bowen ratio (Bo) in tropical rainforests in the FLUXNET2015 database either exhibited little seasonal trend, one seasonal peak, or two peaks. Volumetric water content (VWC) and VPD explained a trivial amount of the variability of LE and Bo in some of the tropical rainforests including the study ecosystem, but were strong controls in others, suggesting differences in stomatal regulation and/or the partitioning between evaporation and transpiration. Results demonstrate important differences in the seasonal patterns in water and energy exchange across different tropical rainforest ecosystems that need to be understood to quantify how ongoing changes in tropical rainforest extent will impact the global climate system.

PENGARUH KONSENTRASI CUKA KAYU DAN MEDIA TANAM PADA PERTUMBUHAN SETEK PUCUK PANGAL (Baccaurea bracteata Muell)

Pangal is one of the peat forest plant species that can be used to restore degraded peat forest. The purpose of this study was to obtain the most suitable concentration of wood vinegar for the growth of pangal bud cuttings planted in cocopeat or cocopeat growing media + hust charcoal. This study uses the experimental split plot method with a complete randomized pattern (CRD). Treatment factor as the main plot of media with 2 levels of (cocopeat and cocopeat + husk charcoal 2:1) and subplot with concentration Wood vinegar 3 levels (3%, 3.5% and 4%) with 5 replications. The results showed that the percentage of live of cuttings and the highest rooted percentage was in a combination of treatment with media and 4% wood vinegar concentration with a percentage of live of the cut reaching 100%. Significant treatment increases the length of primary roots and the number of roots found in the growth of thr primary root length is (4.19 cm) in the treatment of cocopeat media and the concentration of 3% wood vinegar can increase the growth of the primary roots length, for the highest average number of primary roots which is 6.40 also in the same treatment the same is cocopeat media with a dose of 3% wood vinegar. Significant treatment increases thenumber of roots is found in the treatment of secondary root with an average value 33.6 was in the of cocopeat media treatment with 4% wood vinegar dose, while the highest number of leaves with an average 6.60 was in the treatment of cocopeat + husk charcoal with 4% wood vinegar concentration. Wood vinegar concentration and the planting média that are most suitable for shoots cuttings are the concentration of wood vinegar 3% and 4% which can be applied to cocopeat media either without or with the addition of husk charcoal.Keywords: Baccaurea bracteata Muell, growth media, shoot cutting, wood vinegar

Environmental impacts as affected by different oil palm cropping systems in tropical peatlands

Tropical peatlands are globally important for their high carbon storage and unique biodiversity, but are currently under severe threat in South East Asia from expansion of oil palm plantations. A large part of this expansion in Peninsular Malaysia arises from small-holder oil palm plantations that follow varied cropping practices, yet their impact on the environment is largely unexplored. This research aimed to study and evaluate the environmental and belowground microbial impacts of different smallholder cropping systems relative to forested peatlands in North Selangor, Peninsular Malaysia. Specifically, GHG measurements using closed chambers, and peat sampling were carried out in both wet and dry seasons. Microbial phenotypic community structure was determined using phospholipid fatty acid (PLFA) analysis. Relative to forested peatlands, the agricultural plantations had increased pH, temperature and bulk density, decreased organic content, and peat moisture, with a pineapple intercropping site as the only exception. These effects were most pronounced in 2nd generation mono-cropping systems. Soil microbial community structure, dominated by Gram-positive bacteria under all land-use types, differed significantly between agricultural sites and forest, and also showed significant seasonal variation. There was a general increase in non-specific fatty acids and a decrease in Gram-positive fatty acids in agricultural sites from forest, however microbial community structure were similar in most agricultural sites. CO2 emissions were greatest at the forest site and showed no seasonal variations, however most of the forest CO2 emissions were most likely due to high autotrophic contribution from roots. CH4 emissions were under 1 mg m−2 h−1 for all the agricultural sites, while forest peat surface absorbed similar low quantity of CH4. Overall, the changes in peat properties and loss of C was greatest in the 2nd generation mono-cropping, while the intercropping systems ameliorated these effects by maintaining most of the forest peat organic content and causing relatively smaller changes in pH, moisture and bulk density. It is clear that oil palm intercropping have an ameliorating effect on environmental impacts caused by the expansion of oil palm plantations into peatlands.

Impacts of peat-forest smoke on urban PM2.5 in the Maritime Continent during 2012–2015: Carbonaceous profiles and indicators

This study characterizes impacts of peat-forest (PF) smoke on an urban environment through carbonaceous profiles of >260 daily PM2.5 samples collected during 2012, 2013 and 2015. Organic carbon (OC) and elemental carbon (EC) comprising eight carbonaceous fractions are examined for four sample groups – non-smoke-dominant (NSD), smoke-dominant (SD), episodic PM2.5 samples at the urban receptor, and near-source samples collected close to PF burning sites. PF smoke introduced much larger amounts of OC than EC, with OC accounting for up to 94% of total carbon (TC), or increasing by up to 20 times in receptor PM2.5. SD PM2.5 at the receptor site and near-source samples have OC3 and EC1 as the dominant fractions. Both sample classes also exhibit char-EC >1.4 times of soot-EC, characterizing smoldering-dominant PF smoke, unlike episodic PM2.5 at the receptor site featuring large amounts of pyrolyzed organic carbon (POC) and soot-EC. Relative to the mean NSD PM2.5 at the receptor, increasing strength of transboundary PF smoke enriches OC3 and OC4 fractions, on average, by factors of >3 for SD samples, and >14 for episodic samples. A peat-forest smoke (PFS) indicator, representing the concentration ratio of (OC2+OC3+POC) to soot-EC, shows a temporal trend satisfactorily correlating with an organic marker (levoglucosan) of biomass burning. The PFS indicator systematically differentiates influences of PF smoke from source to urban receptor sites, with a progressive mean of 3.6, 13.4 and 20.1 for NSD, SD and episodic samples respectively at the receptor site, and 54.7 for the near-source PM2.5. A PFS indicator of ≥5.0 is proposed to determine dominant influence of transboundary PF smoke on receptor urban PM2.5 in the equatorial Asia with ∼90% confidence. Assessing >2900 hourly OCEC data in 2017–2018 supports the applicability of the PFS indicator to evaluate hourly impacts of PF smoke on receptor urban PM2.5 in the Maritime Continent.

Ecological aspects and genetic diversity of Shorea balangeran in two forest types of Muara Kendawangan Nature Reserve, West Kalimantan, Indonesia

Abstract. Indriani F, Siregar U, Matra DD, Siregar IZ. 2019. Ecological aspects and genetic diversity of Shorea balangeran in two forest types of Muara Kendawang Nature Reserve, West Kalimantan, Indonesia. Biodiversitas 20: 482-488. Shorea balangeran (balangeran) belongs to the Dipterocarpaceae family that is distributed naturally in Indonesia with a wide range of ecological conditions including peat swamp and heath forests. Good adaptability of S. balangeran remains unknown concerning molecular (genetic) responses that are important to provide scientific knowledge for supporting forest restoration, especially for peatland restoration efforts. The main objective of this research was to analyze the ecological aspects and genetic diversity of S. balangeran in two types of forests, namely: peat forests (wetland) and heath forests (dry land). Field research was conducted in Muara Kendawangan Nature Reserve, West Kalimantan following standard vegetation analysis by establishing purposively sample plots (50 m x 50 m). Genetic diversity was assessed by RAPD analysis using ten random polymorphic primers. Results showed that both in heath and peat forests, S. balangeran was dominant, but only at pole and tree stages indicating that poor regeneration capacity of S. balangeran. This finding also confirmed the critically endangered status of S. balangeran as listed in the IUCN Red List of Threatened Species. Genetic analysis using RAPD did not show a clustering of S. balangeran between peat forest and heath forest populations, indicating that S. balangeran has good adaptability to grow in both forest types.

KEANEKARAGAMAN JENIS TUMBUHAN PAKU-PAKUAN (PTERIDOPHYTA) DAN KONDISI TEMPAT TUMBUHNYA PADA HUTAN RAWA GAMBUT SEKUNDER DAN LAHAN GAMBUT TERBUKA

The activities of the community around the peat swamp forest cause disruption of the ecosystem from the sustainability of the forest area's resources. Land clearing and peatland fires also affect the presence of ferns. The new environmental conditions due to changes in land cover cause ferns to be affected by these changes. Kuala Dua Village Kubu Raya Regency has secondary peat swamp forest and open peat land due to fires 3-4 years earlier so it is overgrown with a variety of new types of flora, one of which is a type of fern. The objective of the study is to describe species diversity of ferns and their site conditions in secondary peat swamp forests and open peatlands of Kuala Dua Village, Kubu Raya District. This research was conducted with survey method using multiple plot samples. The plots determination was done by purposive sampling which was taken place on the site where there were many species of ferns land. Three plots were on each land covered condition with a plot size of 5 m x 5 m that divided into 25 of a 1 m x 1 m sub plots. The results show that 5 species of ferns found in peat swamp forest and 4 species of ferns were found on open peatlands. The species that has the highest INP value in the forest was Asplenium belangeri and the species that has the INP value in open peatland was Nephrolefis falcata. Dominant Index, Spesies Diversity Index and Spesies Abudance Index were 0,12 and 0,18; 0,30 and 0,36; 0,51 and 0,52 on the forest and open peatland respectively. The Similarity Index value (IS) of ferns in secondary peat swamp forest and open peatland is 44%. The study shows dissimility of species fern in peat swamp forests and open peatlands.Keywords: Open peatland, Pteridophyta, secondary peat swamp forest

Eradication test of Acasia crassicarpa in peat forest

Abstract. Mawazin, Octavia D. 2018. Eradication test of Acasia crassicarpa in peat forest. Pros Sem Nas Masy Biodiv Indon 5: 324-329. Acacia crassicarpa is classified as a fast-growing tree species which is the main species in building industrial plantations on peatlands which have an invasive potential. Eradication tests were carried out on A.crassicarpa plants that had grown wildly in the peat land natural forest areas which were located in Tasik Besar Serkap Forest Management Unit (FMU/ KPH) and bordered by A. crassicarpa industrial plantations. The eradication method was carried out by cutting plants, peeling bark, cutting bole followed by polishing stump with active ingredient of triclopyr 4.8 g/L, and cutting bole without polishing stump. The eradication application is carried out at the beginning of the dry season in April to minimize the growth of new branches or shoots from trees that have been cut down. The eradication technique of extracting the crassicarpa seedlings was carried out on tillers that had a diameter of less than 7 cm, and a diameter of more than 7 cm should be carried out by another technique because extraction would not be possible (unplugged). At 6 months after the eradication application was obtained the results of the effectiveness of eradication techniques in controlling A. crassicarpa were100%, 93.3%, and 73.3% respectively for eradication treatment which was cut down and immediately smeared with chemicals; eradication by skin stripping techniques; and eradication which was only done by logging. Eradication of A. crassicarpa by logging has the lowest effectiveness because some of the trees cut down will sprout again. The physical and chemical combination eradication techniques (cut down and smeared with active ingredients) produce the most effective eradication because all treatment units (trees) have died. In terms of the length of time for each treatment unit, it takes respectively around 10-15 minutes, 6-8 minutes, 4-5 minutes, and 2-3 minutes each for skin stripping treatment, felling with basting, felling, and direct removal. Based on the results of the study, it is recommended that the most effective application of A. crassicarpa eradication be carried out by a combination felling technique with basting.

An Estimate of the Financial Cost of Peatland Restoration in Indonesia

The peat forests of Indonesia have experienced extensive deforestation and degradation over recent decades. High demand for Indonesian timber and plantation development has driven large-scale draining and clearing of peat forest, resulting in extensive fires and smoke haze problems across the region. These fires caused more than 100,000 premature deaths in 2015 alone, increased the pressure on several already threatened species, and placed Indonesia among the top greenhouse gas emitting countries globally. In response, the Indonesian government has launched an initiative to restore more than 2 million ha of peatland between now and 2020. Although there is a substantial body of academic literature that deals with technical aspects of tropical peatland restoration, little is published on the costs of tropical peatland restoration activities. In this study, we examine the case of peatland restoration in the provinces of Kalimantan, Sumatra, and Papua in Indonesia, and propose a restoration activity classification scheme based on fire, drainage, and logging history of peatland areas. We use this scheme to identify the restoration activity needs of different areas and then develop a preliminary gross financial cost estimate for the restoration activities proposed under the national 2-million-ha peatland restoration initiative. We find that it is likely to cost more than US$4.6 billion to complete the national 2-million-ha restoration initiative, which is substantially more than the funds currently allocated to the challenge across Indonesian and international donor budgets.

Prediction of Peat Forest Fires Using Wavelet and Backpropagation

One of the causes of smog as well as climate damage, particularly in Palangka Raya, Center Kalimantan, are peat forest fires. There are a lot of losses inflicted by the smog including the increasing number of people who suffer respiratory infection (ARI) due to polluted air and any other related aspects. Peat fires are problematic to overcome because the locations of fires are difficult to be accessed. This paper focuses on building the system to predict the distribution of peat forest fire hotspots by utilizing satellite imagery. In designing the system for predicting the fire hotspots distribution, wavelet orthogonal was used as the initial processing of mapping the distribution of peat forest fire hotspots. Meanwhile, backpropagation method was used to identify the fire hotspot distribution patterns of peat forest fire in this system. From the result of the data tested which had been done for predicting the peat forest fire hotspots, the decomposition image obtained using Haar wavelet had the highest percentage of accuracy to recognize the fire hotspots, which is 90%. The recency of this system was its ability to predict the peat forest fire hotspots distribution which can be used as peat forest fires prevention, especially in Palangka Raya, Central Kalimantan.

Getting forest science to policy discourse: a theory-based outcome assessment of a global research programme

This paper presents an assessment of the outcomes of research carried out under the Sustainable Wetlands Adaptation and Mitigation Programme (SWAMP). SWAMP aimed to inform national and international climate policy and practice by developing tools and methods to quantify greenhouse gas (GHG) emissions, carbon stocks and flux in tropical wetlands due to land use, land-use change and forestry (LULUCF). This assessment modelled SWAMP's intended outcomes as a theory of change (ToC) and used qualitative methods to test the ToC and to evaluate whether and how the outcomes were achieved. It found that SWAMP research has helped raise academic and policy interest in wetlands, mangroves and peat forests as carbon reservoirs, and that SWAMP's recommendations informed policy discourse and supported the development of technical guidance and strategies of sustainable wetland management. However, the research had a weak effect on international and Indonesian climate change policies compared to other factors. The Paris Agreement and Indonesia's nationally determined contribution (NDC) do not include the quantification of carbon stocks from mangroves, which are not all located in the forest areas. Knowledge translation was achieved through a variety of mechanisms, with direct engagement identified as particularly important. The outcome evaluation approach proved useful as a way of conceptualising and organising the analysis of research impact on development outcomes.

Diversity and floristic differentiation of South Brazilian coastal plain Atlantic forests based on herb layer life-forms

The Brazilian coastal plains comprise very different forest types commonly distinguished by soil conditions. The study of distinct life-forms in the herb layer might contribute to the understanding of forest structure and to the circumscription of forest types. In this paper, we investigated the variation in composition and diversity of the herb layer in three coastal forest types (Dune, Peat and Rain forests) within the Brazilian Atlantic Forest complex and examined if coastal forests’ differences, usually characterized by adult trees, are matched by herb layer features. We sampled the herb layer (≤1 m in height) in 23 forest fragments, classifying species in climbers, herbs, palms, shrubs and trees. Peat forest had lower overall diversity relative to Dune and Rain forests. Higher tree species richness and abundance in Rain forest, and higher herbaceous richness and abundance in Peat forest were the major differences between these forest types. Dune forest was similar to Peat forest in relation to herbaceous species and to Rain forest in relation to tree species indicating a transition environment between both forests. Composition between forests is distinguishable for trees and shrubs, but not for climbers and herbaceous species. Thus, the distinctions among these forest types are complex when taking into account the herb layer. Our findings demonstrate the importance of including the herb layer life-forms for a better understanding of the diversity and complexity of tropical and subtropical forests, especially the Atlantic coastal forests, which should be primarily classified as flooded and non-flooded at a regional scale.

GEOGAME ON THE PEAT: DESIGNING EFFECTIVE GAMEPLAY IN GEOGAMES APP FOR HAZE MITIGATION

Abstract. The Southeast Asian Haze in 2014 and 2015 is the worst transboundary haze episodes recorded to date. The haze mainly originated from burning of biomass material in peatland area, caused major health problems and economic losses. Peat forest conversion to forest and agriculture industry by utilizing drainage canals is one of main fire drivers that need to be restored, while conflicts on land and livelihood further adding complexity on the issue. Water and peatland management are among the key activities for reducing the peat fire risk and for eliminating the transboundary haze problems. Geospatial data have been collected in peatland areas in Indonesia to support hydrological restoration plans to prevent drying of peat biomasses. Aside from satellite and UAV data, crowdsourcing could also be conducted by engaging residents in collecting spatial data on peat environment while at the same time raising awareness on peatland management and peat fire prevention. This paper elaborates our findings in developing a Geogame App for mitigating haze in peatland area. The study area is situated in Padang Island, Riau, Indonesia. The gamification was implemented as a location-based, augmented reality adventure game. The storyline revolves around peat-related theme, with game elements represent different aspects of peatland management. The game incorporates real-world data as a game element, which also serves as a platform for collecting data around the users. Game mockup and use case scenario are provided to model the spatial data collected through the game for decision makers related to peat fire management.

Spatial Analysis of The Correlation Between Hot Spot Distribution and Land Cover Type in Sumatra, Indonesia

Based on land cover data of 2015, Sumatra is dominated by shrubs, bushes, plantations with hardwoods, and plantations. It is the island with the largest peat distribution in Indonesia. Peatland forest map provided by Ministry of Environment and Forestry in 2015 represent that the total area of peatland in Sumatra is about 9.6 million hectares, mostly located in Riau, Jambi, and South Sumatra Province. Fire incidents can be indicated through hot spots distribution data. The data used is the distribution of hot spot of Sumatra in 2005–2016. The purpose of this study was to analyze the pattern of hot spot distribution and its relations with land cover changes. Overlay results indicate that 31.75% fires occur in shrubs and bushes, 20.87% in plantations with hardwoods, 16.60% in other natural cleared areas, 14.55% in forest crops, and the rest spreads in lowland crops, dry season crops, and swamp / peat forests. The highest hot spots are in 2005 and 2015 due to the El Nino effect that causes prolonged drought. Available land cover data indicates a change during 1990 through 2011. Most of peat land turn into plantation between 1990 to 2000. The result of overlay of hot spot distribution with land cover data from 2006–2015 shows that forest fires mostly occur in industrial plantation forest. This can be seen from the land cover classification where previously a plantation forest, then it is burned into a field and become an industrial plantation forest. Nevertheless, this analysis still need to be validated through ground truth to check the actual land cover and land use in field.

Termite diversity and species composition in heath forests, mixed dipterocarp forests, and pristine and selectively logged tropical peat swamp forests in Brunei

Since the 1970s Southeast Asian peat swamp forests have been increasingly threatened by anthropogenic disturbance. Peat swamps act as refuge for many endangered species, and they may turn into a net producer of CO2 and greatly contribute to climate change if cleared and drained. As one of the main invertebrate decomposers in the tropics, termites are likely to play a major role in peat forests. In this paper, we used a grid-based sampling plot protocol to sample termites in Brunei. We sampled termite communities in pristine and selectively logged peat swamp forests, that we compared with termite communities sampled in heath and dipterocarp forests. More precisely, we determined: (i) termite species diversity in peat swamp forests, and (ii) how termites respond to peat swamp logging. We found that species richness was the highest in the mixed dipterocarp forest. Selective logging had limited impact on species richness in peat swamp forest, suggesting that termite communities are resilient to limited amount of perturbations. Further data are needed to better understand the impact peat swamp clearance has on termite populations and their contribution to climate change.

Eddy Covariance Measurements of Methane Flux at a Tropical Peat Forest in Sarawak, Malaysian Borneo

AbstractTropical biogenic sources are a likely cause of the recent increase in global atmospheric methane concentration. To improve our understanding of tropical methane sources, we used the eddy covariance technique to measure CH4 flux (FCH4) between a tropical peat forest ecosystem and the atmosphere in Malaysian Borneo over a 2‐month period during the wet season. Mean daily FCH4 during the measurement period, on the order of 0.024 g C‐CH4·m−2·day−1, was similar to eddy covariance FCH4 measurements from tropical rice agroecosystems and boreal fen ecosystems. A linear modeling analysis demonstrated that air temperature (Tair) was critical for modeling FCH4 before the water table breached the surface and that water table alone explained some 20% of observed FCH4 variability once standing water emerged. Future research should measure FCH4 on an annual basis from multiple tropical ecosystems to better constrain tropical biogenic methane sources.

Estimation of carbon emission from peatland fires using Landsat-8 OLI imagery in Siak District, Riau Province

The study was conducted in three land cover conditions (secondary peat forest, shrub land, and palm plantation) that were burned in the Siak District, Riau Province, Indonesia year 2015. Measurement and calculation carbon emission from soil and vegetation of peatland should be done accurately to be implemented on climate change mitigation or greenhouse gases mitigation. The objective of the study was to estimate the carbon emission caused peatland fires in the Siak District, Riau Province, Indonesia year 2015. Estimated carbon emissions were performed using visual method and digital method. The visual method was a method that uses on-screen digitization assisted by hotspot data, the presence of smoke, and fire suppression data. The digital method was a method that uses the Normalized Burn Ratio (NBR) index. The estimated carbon emissions were calculated using the equation that was developed from IPCC 2006 in Verified Carbon Standard 2015. The results showed that the estimation of carbon emissions from fires from above the peat soil surface were higher than the carbon emissions from the peat soil. Carbon emissions above the peat soil surface of 1376.51 ton C/ha were obtained by visual method while 3984.33 ton C/ha were obtained by digital method. Peatland carbon emissions of 6.6 x 10-4 ton C/ha were obtained by visual method, whereas 2.84 x 10-3 ton C/ha was obtained by digital method. Visual method and digital method using remote sensing must be combined and developed in order to carbon emission values will be more accurate.

Land cover changes reduce net primary production in tropical coastal peatlands of West Kalimantan, Indonesia

Tropical peat swamp forests are carbon-rich ecosystems that have been threatened by high rates of land use change (LUC). Despite the ecosystem’s shifts from sequestering carbon (C) to emitting carbon, few studies have quantified the changes in ecosystem productivity associated with LUC in tropical peatlands. This study quantified net primary production (NPP) in intact peat swamp forests (PSF), logged forests (LPSF), early seral sites (ES), and smallholder oil palm plantations (OP) in a peat dome of West Kalimantan, Indonesia. All sites were dominated by peat forest prior to deforestation. The NPP of intact forests was 13.2 Mg C ha−1 year−1 making it among the world’s most productive terrestrial ecosystems, exceeding that of many tropical rainforests and similar to the most productive mangrove ecosystems (12.9 Mg C ha−1 year−1). Land cover change resulted in large shifts in NPP. Logged forest and early seral sites were < 11.1 Mg C ha−1 year−1. The NPP of oil palm plantations was 3.7 Mg C ha−1 year−1. Aboveground NPP was recorded at 10.5 Mg C ha−1 year−1 in forests, exceeding the NPP of LPSF, ES, and OP (8.9, 5.1, and 3.5 Mg C ha−1 year−1, respectively). Early seral sites (5.7 Mg C ha−1 year−1) were estimated to have the highest belowground NPP (p = 0.05). Root productivity in PSF, LPSF, and OP was 2.7, 2.1, and 0.2 Mg C ha−1 year−1, respectively. Land use change and forest degradation have reduced the productivity of tropical peatlands.