The observation of a flock of 1000 Asian Dowitchers (Limnodromus semipalmatus) on the north coast... more The observation of a flock of 1000 Asian Dowitchers (Limnodromus semipalmatus) on the north coast of Java in April 1988 made a significant change to the wintering range of this species.
The observation of a flock of 1000 Asian Dowitchers (Limnodromus semipalmatus) on the north coast... more The observation of a flock of 1000 Asian Dowitchers (Limnodromus semipalmatus) on the north coast of Java in April 1988 made a significant change to the wintering range of this species.
Peat is an important growing medium constituent for Dutch horticulture, but peat excavation may c... more Peat is an important growing medium constituent for Dutch horticulture, but peat excavation may conflict with demands of society such as halting the loss of biodiversity and prevention of carbon emission. Responding to these potential conflicts The Dutch ministry of Agriculture, Nature and Food Quality (currently the Ministry of Economic Affairs, Agriculture and Innovation) commissioned this study to provide insights in "options to enhance the sustainability of the peat supply chain for the Dutch horticulture". Via a combination of literature review and stakeholder interaction the options to enhance the sustainability of the use of peat in horticulture in the Netherlands have been studied and discussed. The main outcomes of the study are that to enhance the sustainability one should focus on already degraded peat areas for extraction and transparency in the supply chain should be increased to be able to have a clear and open communication with the public so enhancing the credibility of the sector. In addition research to new extraction methods to upgrade degraded peat and the development of high quality sustainable alternatives for growing media should be continued. More attention to the after use and rehabilitation of mined areas is needed.
The peat deposits of Southeast Asia are mainly of recent origin (max. 10000 years old) and are om... more The peat deposits of Southeast Asia are mainly of recent origin (max. 10000 years old) and are ombrogenous. They are characterized by a markedly convex surface, rain-fed water supply, with an elevated water table. The peat domes in SE Asia have different shapes, depending on the size between the rivers, the location (e.g. coastal), peat thickness, bulk density, hydraulic conductivity, rain fall per year and the water saturation. Peat domes need surface structures that transform the varying atmospheric water supply into a steady supply to the peat by a combination of limited hydraulic conductivity and large storage capacity. SE-Asian coastal peat domes are controlled by strong self-regulative forces. The lowland peatlands of SE-Asia represent an immense reservoir of fossil carbon and are now responsible for 30% of the global carbon dioxide (CO 2 ) emissions from Land Use, Land Use Change and Forestry. from G. Sieffermann et al., J.O. Rieley and S.E. Page, M.A. Brady, V. Boehm, H. Joosten et al., R. Dommain et al., and J. Couwenberg et al.
The results of a survey of Odonata (dragonflies and damselflies) in the peatlands of Central Kali... more The results of a survey of Odonata (dragonflies and damselflies) in the peatlands of Central Kalimantan, Indonesia, in 2012 are presented. Fifty four species of Odonata found in the area in June-July 2012 are listed, along with brief notes and the locations in which they were found. Of the species found, twelve had not been recorded in Central Kalimantan previously, and of these at least four are completely new to science. Six species, originally described from Central Kalimantan and not recorded any-where since 1953, were rediscovered. At least sixteen of the species found during the survey are considered to be of conservation concern. The discovery of at least four new species to science in a relatively short survey indicates a high probability of occurrence of many more species that are awaiting discovery, and that many undiscovered species may be lost or highly threatened because of the rapid demise of peat swamp forest habitats. A checklist of the Odonata known from Central Kal...
This report provides a review of available scientific information and published literature on imp... more This report provides a review of available scientific information and published literature on impacts of using tropical peat for oil palm cultivation in Southeast Asia. It describes carbon flows and greenhouse gas (GHG) emissions from native and degraded forest and oil palm plantations on peat, as well as other environmental impacts and social and economic aspects of the cultivation of oil palm on peat. Based on the available literature, the report presents conclusions on the gaps in knowledge, uncertainties and confusion in existing datasets.
Forested tropical peatlands in Southeast Asia store at least 42,000 Million tonnes of carbon. Thi... more Forested tropical peatlands in Southeast Asia store at least 42,000 Million tonnes of carbon. This globally significant pool is threatened by peatland drainage, causing peat oxidation and fires. In the PEAT-CO2 project present and future CO 2 emissions were quantified using data on peat extent and depth, present and projected land use, water management practices and decomposition rates. Of the 27.1 million hectares of peatland in Southeast Asia, 12.9 million hectares are currently deforested and mostly drained; this area is increasing rapidly. Current carbon dioxide (CO 2 ) emissions caused by decomposition of drained peatlands alone, not including the effect of peatland fires or forest loss, are calculated at 632 Mt y -1 (range: 355-855 Mt y -1 ), which is equivalent to 2.4% of global emission from fossil fuels. This emission can be reduced if the impact of drainage on peatlands is recognized by peatland managers and policy makers, and improved water management is implemented to ensure conservation of peat carbon stocks and, where possible, of remaining peatland forests. Water management strategies aiming to maintain or restore the high water tables required for peatland conservation are now being developed and piloted in several projects in Indonesia; some preliminary findings of one of these pilots are presented. While uncertainties in the quantification of CO 2 emissions should be reduced, enough is known to justify large-scale implementation of mitigative water management methods in peatlands as a matter of urgency.
Forested tropical peatlands in Southeast Asia store at least 42 000 Million metric tonnes (Mt) of... more Forested tropical peatlands in Southeast Asia store at least 42 000 Million metric tonnes (Mt) of soil carbon. Human activity and climate change threatens the stability of this large pool, which has been decreasing rapidly over the last few decades owing to deforestation, drainage and fire. In this paper we estimate the carbon dioxide (CO 2 ) emissions resulting from drainage of lowland tropical peatland for agricultural and forestry development which dominates the perturbation of the carbon balance in the region. Present and future emissions from drained peatlands are quantified using data on peatland extent and peat thickness, present and projected land use, water management practices and decomposition rates. Of the 27.1 Million hectares (Mha) of peatland in Southeast Asia, 12.9 Mha had been deforested and mostly drained by 2006. This latter area is increasing rapidly because of increasing land development pressures. Carbon dioxide (CO 2 ) emission caused by decomposition of drained peatlands was between 355 Mt y −1 and 855 Mt y −1 in 2006 of which 82% came from Indonesia, largely Sumatra and Kalimantan. At a global scale, CO 2 emission from peatland drainage in Southeast Asia is contributing the equivalent of 1.3% to 3.1% of current global CO 2 emissions from the combustion of fossil fuel. If current peatland development and management practices continue, these emissions are predicted to continue for decades. This warrants inclusion of Correspondence to: A. Hooijer ([email protected]) tropical peatland CO 2 emissions in global greenhouse gas emission calculations and climate mitigation policies. Uncertainties in emission calculations are discussed and research needs for improved estimates are identified.
Erftemeijer, PLA 1988. A survey of coastal wetlands and waterbirds in the Brantas and Solo delta.... more Erftemeijer, PLA 1988. A survey of coastal wetlands and waterbirds in the Brantas and Solo delta. East Java. Asian Wetland Bureau -INTERWADER/PHPA report no.6 Bogor. ... Hoogerwerf, A. 1948. Contribution to the knowledge of the distribution of birds on the ...
Physics and Chemistry of the Earth, Part B: Hydrology, Oceans and Atmosphere, 2000
... of production systems (via eg increased irrigation efficiency, fertiliser use, combating pest... more ... of production systems (via eg increased irrigation efficiency, fertiliser use, combating pests and diseases ... the existing self sufficiency in basic needs or the losses of cultural integrity especially ... the arrival of the French in 1893 established a common property management system ...
... allow payments to such groups and focus some of the pilot initiatives towards community PES a... more ... allow payments to such groups and focus some of the pilot initiatives towards community PES and Bio-rights mechanisms (T. Herman, pers ... WH, Joosten, H., Mantel, S. Murdiyarso, D., Noordwijk, M. van, Rieley, JO, Veldsink, JW, Verhagen, A., Wakker, E., Wind, J., Setiadi, B. and ...
Studies of restoration ecology are well established for northern peatlands, but at an early stage... more Studies of restoration ecology are well established for northern peatlands, but at an early stage for tropical peatlands. Extensive peatland areas in Southeast Asia have been degraded through deforestation, drainage and fire, leading to on-and off-site environmental and socio-economic impacts of local to global significance. To address these problems, landscape-scale restoration measures are urgently required. This paper reviews and illustrates, using information from on-going trials in Kalimantan, Indonesia, the current state of knowledge pertaining to (i) land-cover dynamics of degraded peatlands, (ii) vegetation rehabilitation, (iii) restoration of hydrology, (iv) rehabilitation of carbon sequestration and storage, and (v) promotion of sustainable livelihoods for local communities. For a 4500 km 2 study site in Central Kalimantan, Indonesia, we show a 78% reduction in forest cover between 1973 and 2003 and demonstrate that fire, exacerbated by drainage, is the principal driver of land-use change. Progressive vegetation succession follows infrequent, lowintensity fires, but repeated and high-intensity fires result in retrogressive succession towards non-forest communities. Re-wetting the peat is an important key to vegetation restoration and protection of remaining peat carbon stocks. The effectiveness of hydrological restoration is discussed and likely impacts on greenhouse gas emissions evaluated. Initial results indicate that raised water levels have limited short-term impact on reducing CO 2 emissions, but could be critical in reducing fire risk. We conclude that successful restoration of degraded peatlands must be grounded in scientific knowledge, relevant to socio-economic circumstances, and should not proceed without the consent and co-operation of local communities.
The observation of a flock of 1000 Asian Dowitchers (Limnodromus semipalmatus) on the north coast... more The observation of a flock of 1000 Asian Dowitchers (Limnodromus semipalmatus) on the north coast of Java in April 1988 made a significant change to the wintering range of this species.
The observation of a flock of 1000 Asian Dowitchers (Limnodromus semipalmatus) on the north coast... more The observation of a flock of 1000 Asian Dowitchers (Limnodromus semipalmatus) on the north coast of Java in April 1988 made a significant change to the wintering range of this species.
Peat is an important growing medium constituent for Dutch horticulture, but peat excavation may c... more Peat is an important growing medium constituent for Dutch horticulture, but peat excavation may conflict with demands of society such as halting the loss of biodiversity and prevention of carbon emission. Responding to these potential conflicts The Dutch ministry of Agriculture, Nature and Food Quality (currently the Ministry of Economic Affairs, Agriculture and Innovation) commissioned this study to provide insights in "options to enhance the sustainability of the peat supply chain for the Dutch horticulture". Via a combination of literature review and stakeholder interaction the options to enhance the sustainability of the use of peat in horticulture in the Netherlands have been studied and discussed. The main outcomes of the study are that to enhance the sustainability one should focus on already degraded peat areas for extraction and transparency in the supply chain should be increased to be able to have a clear and open communication with the public so enhancing the credibility of the sector. In addition research to new extraction methods to upgrade degraded peat and the development of high quality sustainable alternatives for growing media should be continued. More attention to the after use and rehabilitation of mined areas is needed.
The peat deposits of Southeast Asia are mainly of recent origin (max. 10000 years old) and are om... more The peat deposits of Southeast Asia are mainly of recent origin (max. 10000 years old) and are ombrogenous. They are characterized by a markedly convex surface, rain-fed water supply, with an elevated water table. The peat domes in SE Asia have different shapes, depending on the size between the rivers, the location (e.g. coastal), peat thickness, bulk density, hydraulic conductivity, rain fall per year and the water saturation. Peat domes need surface structures that transform the varying atmospheric water supply into a steady supply to the peat by a combination of limited hydraulic conductivity and large storage capacity. SE-Asian coastal peat domes are controlled by strong self-regulative forces. The lowland peatlands of SE-Asia represent an immense reservoir of fossil carbon and are now responsible for 30% of the global carbon dioxide (CO 2 ) emissions from Land Use, Land Use Change and Forestry. from G. Sieffermann et al., J.O. Rieley and S.E. Page, M.A. Brady, V. Boehm, H. Joosten et al., R. Dommain et al., and J. Couwenberg et al.
The results of a survey of Odonata (dragonflies and damselflies) in the peatlands of Central Kali... more The results of a survey of Odonata (dragonflies and damselflies) in the peatlands of Central Kalimantan, Indonesia, in 2012 are presented. Fifty four species of Odonata found in the area in June-July 2012 are listed, along with brief notes and the locations in which they were found. Of the species found, twelve had not been recorded in Central Kalimantan previously, and of these at least four are completely new to science. Six species, originally described from Central Kalimantan and not recorded any-where since 1953, were rediscovered. At least sixteen of the species found during the survey are considered to be of conservation concern. The discovery of at least four new species to science in a relatively short survey indicates a high probability of occurrence of many more species that are awaiting discovery, and that many undiscovered species may be lost or highly threatened because of the rapid demise of peat swamp forest habitats. A checklist of the Odonata known from Central Kal...
This report provides a review of available scientific information and published literature on imp... more This report provides a review of available scientific information and published literature on impacts of using tropical peat for oil palm cultivation in Southeast Asia. It describes carbon flows and greenhouse gas (GHG) emissions from native and degraded forest and oil palm plantations on peat, as well as other environmental impacts and social and economic aspects of the cultivation of oil palm on peat. Based on the available literature, the report presents conclusions on the gaps in knowledge, uncertainties and confusion in existing datasets.
Forested tropical peatlands in Southeast Asia store at least 42,000 Million tonnes of carbon. Thi... more Forested tropical peatlands in Southeast Asia store at least 42,000 Million tonnes of carbon. This globally significant pool is threatened by peatland drainage, causing peat oxidation and fires. In the PEAT-CO2 project present and future CO 2 emissions were quantified using data on peat extent and depth, present and projected land use, water management practices and decomposition rates. Of the 27.1 million hectares of peatland in Southeast Asia, 12.9 million hectares are currently deforested and mostly drained; this area is increasing rapidly. Current carbon dioxide (CO 2 ) emissions caused by decomposition of drained peatlands alone, not including the effect of peatland fires or forest loss, are calculated at 632 Mt y -1 (range: 355-855 Mt y -1 ), which is equivalent to 2.4% of global emission from fossil fuels. This emission can be reduced if the impact of drainage on peatlands is recognized by peatland managers and policy makers, and improved water management is implemented to ensure conservation of peat carbon stocks and, where possible, of remaining peatland forests. Water management strategies aiming to maintain or restore the high water tables required for peatland conservation are now being developed and piloted in several projects in Indonesia; some preliminary findings of one of these pilots are presented. While uncertainties in the quantification of CO 2 emissions should be reduced, enough is known to justify large-scale implementation of mitigative water management methods in peatlands as a matter of urgency.
Forested tropical peatlands in Southeast Asia store at least 42 000 Million metric tonnes (Mt) of... more Forested tropical peatlands in Southeast Asia store at least 42 000 Million metric tonnes (Mt) of soil carbon. Human activity and climate change threatens the stability of this large pool, which has been decreasing rapidly over the last few decades owing to deforestation, drainage and fire. In this paper we estimate the carbon dioxide (CO 2 ) emissions resulting from drainage of lowland tropical peatland for agricultural and forestry development which dominates the perturbation of the carbon balance in the region. Present and future emissions from drained peatlands are quantified using data on peatland extent and peat thickness, present and projected land use, water management practices and decomposition rates. Of the 27.1 Million hectares (Mha) of peatland in Southeast Asia, 12.9 Mha had been deforested and mostly drained by 2006. This latter area is increasing rapidly because of increasing land development pressures. Carbon dioxide (CO 2 ) emission caused by decomposition of drained peatlands was between 355 Mt y −1 and 855 Mt y −1 in 2006 of which 82% came from Indonesia, largely Sumatra and Kalimantan. At a global scale, CO 2 emission from peatland drainage in Southeast Asia is contributing the equivalent of 1.3% to 3.1% of current global CO 2 emissions from the combustion of fossil fuel. If current peatland development and management practices continue, these emissions are predicted to continue for decades. This warrants inclusion of Correspondence to: A. Hooijer ([email protected]) tropical peatland CO 2 emissions in global greenhouse gas emission calculations and climate mitigation policies. Uncertainties in emission calculations are discussed and research needs for improved estimates are identified.
Erftemeijer, PLA 1988. A survey of coastal wetlands and waterbirds in the Brantas and Solo delta.... more Erftemeijer, PLA 1988. A survey of coastal wetlands and waterbirds in the Brantas and Solo delta. East Java. Asian Wetland Bureau -INTERWADER/PHPA report no.6 Bogor. ... Hoogerwerf, A. 1948. Contribution to the knowledge of the distribution of birds on the ...
Physics and Chemistry of the Earth, Part B: Hydrology, Oceans and Atmosphere, 2000
... of production systems (via eg increased irrigation efficiency, fertiliser use, combating pest... more ... of production systems (via eg increased irrigation efficiency, fertiliser use, combating pests and diseases ... the existing self sufficiency in basic needs or the losses of cultural integrity especially ... the arrival of the French in 1893 established a common property management system ...
... allow payments to such groups and focus some of the pilot initiatives towards community PES a... more ... allow payments to such groups and focus some of the pilot initiatives towards community PES and Bio-rights mechanisms (T. Herman, pers ... WH, Joosten, H., Mantel, S. Murdiyarso, D., Noordwijk, M. van, Rieley, JO, Veldsink, JW, Verhagen, A., Wakker, E., Wind, J., Setiadi, B. and ...
Studies of restoration ecology are well established for northern peatlands, but at an early stage... more Studies of restoration ecology are well established for northern peatlands, but at an early stage for tropical peatlands. Extensive peatland areas in Southeast Asia have been degraded through deforestation, drainage and fire, leading to on-and off-site environmental and socio-economic impacts of local to global significance. To address these problems, landscape-scale restoration measures are urgently required. This paper reviews and illustrates, using information from on-going trials in Kalimantan, Indonesia, the current state of knowledge pertaining to (i) land-cover dynamics of degraded peatlands, (ii) vegetation rehabilitation, (iii) restoration of hydrology, (iv) rehabilitation of carbon sequestration and storage, and (v) promotion of sustainable livelihoods for local communities. For a 4500 km 2 study site in Central Kalimantan, Indonesia, we show a 78% reduction in forest cover between 1973 and 2003 and demonstrate that fire, exacerbated by drainage, is the principal driver of land-use change. Progressive vegetation succession follows infrequent, lowintensity fires, but repeated and high-intensity fires result in retrogressive succession towards non-forest communities. Re-wetting the peat is an important key to vegetation restoration and protection of remaining peat carbon stocks. The effectiveness of hydrological restoration is discussed and likely impacts on greenhouse gas emissions evaluated. Initial results indicate that raised water levels have limited short-term impact on reducing CO 2 emissions, but could be critical in reducing fire risk. We conclude that successful restoration of degraded peatlands must be grounded in scientific knowledge, relevant to socio-economic circumstances, and should not proceed without the consent and co-operation of local communities.
Uploads
Papers by Marcel Silvius