Peat Landscape Research Articles

Poetic inquiry to explore the relational values of a transforming peat landscape

Abstract Restoring degraded peatlands is a promising strategy for mitigating carbon emissions. Large‐scale landscape transformations, such as rewetting of land used for intensive agriculture, often lead to conflicts. Elicitation of the relational values acting as barriers to landscape transformation may support the resolution or taming of such conflicts. This study aimed to explore the relational values associated with a transforming peatland site in Northern Germany. We focused on the value of living and non‐living peat landscape elements; cultural heritage values and identities; educational values; spiritual values; recreational values; and sensory, affective and cognitive experiences. Additionally, we sought to understand how past landscape changes have influenced these values. We conducted interviews with land managers and local residents. Using an art‐based research method, we created six thematic participant‐voiced poems that capture the diverse peatland values. Subsequent interpretation of these poems revealed three key observations: the importance of multisensory experiences; the significance of specific living elements; and the deep cultural and historical values linked to peat landscapes. Landscape changes impact peat landscape values, potentially weakening bonds between people and the peatland. Our study indicates that considering the cultural and historical significance of landscapes may prevent conflicts and foster support for peatland restoration. Ensuring the well‐being of those living and working in these areas requires value‐inclusive landscape planning that embraces a broader focus on relational values. This also involves the potential promotion of value shifts. Such an approach may cultivate a more sustainable and inclusive transformation of the landscape. Read the free Plain Language Summary for this article on the Journal blog.

Drainage ditches are year‐round greenhouse gas hotlines in temperate peat landscapes

Abstract Greenhouse gas (GHG) emissions from drained peatlands have been studied extensively. Considerably less attention has been paid to the emissions from the ditches used to drain peatlands. High within‐ditch GHG production and lateral inflow of GHGs may lead to ditches emitting considerable amounts of GHGs on the landscape scale. We quantified annual emissions of ebullitive and diffusive methane (CH4), carbon dioxide (CO2), and nitrous oxide (N2O) in 10 drainage ditches in intensively used temperate peatlands used for dairy farming, in The Netherlands. Additionally, we assessed water and sediment quality to determine proxies for emissions via the two emission pathways. The mean annual emissions from the studied ditches varied between 3.57 and 60.1 g CO2‐eq. m−2 day−1 (based on a global warming potential over a 100‐year timeframe), where CO2 contributed on average 43% (ranging between 1.9 and 22.0 g CO2 m−2 day−1) and diffusive CH4 contributed 16% (0.1–16.5 g CO2‐eq. m−2 day−1) to the total GHG emission. Ebullition of CH4 made up nearly half of the total GHG emission (40%, 1.3–40.9 g CO2‐eq. m−2 day−1). N2O emissions were mostly low. CO2 emissions were higher in winter months, while CH4 ebullition was higher during spring and summer. Diffusive CH4 emissions did not show a seasonal pattern. The mean emission factor, the estimate of average emissions per unit area (EF), for CH4 was 2144 kg CH4 ha−1 year−1, which is two times higher than the tier 1 EF reported by the IPCC (with underrepresented ebullition data), underlining the high variability of ditch emissions. Ditch emissions were also higher than the EF used for the surrounding drained peatlands indicating that ditch emissions can be important on the landscape scale and should be considered to be included in national greenhouse gas reporting.

CH4 and N2 O emissions from smallholder agricultural systems on tropical peatlands in Southeast Asia.

There are limited data for greenhouse gas (GHG) emissions from smallholder agricultural systems in tropical peatlands, with data for non-CO2 emissions from human-influenced tropical peatlands particularly scarce. The aim of this study was to quantify soil CH4 and N2 O fluxes from smallholder agricultural systems on tropical peatlands in Southeast Asia and assess their environmental controls. The study was carried out in four regions in Malaysia and Indonesia. CH4 and N2 O fluxes and environmental parameters were measured in cropland, oil palm plantation, tree plantation and forest. Annual CH4 emissions (in kg CH4 ha-1 year-1 ) were: 70.7 ± 29.5, 2.1 ± 1.2, 2.1 ± 0.6 and 6.2 ± 1.9 at the forest, tree plantation, oil palm and cropland land-use classes, respectively. Annual N2 O emissions (in kg N2 O ha-1 year-1 ) were: 6.5 ± 2.8, 3.2 ± 1.2, 21.9 ± 11.4 and 33.6 ± 7.3 in the same order as above, respectively. Annual CH4 emissions were strongly determined by water table depth (WTD) and increased exponentially when annual WTD was above -25 cm. In contrast, annual N2 O emissions were strongly correlated with mean total dissolved nitrogen (TDN) in soil water, following a sigmoidal relationship, up to an apparent threshold of 10 mg N L-1 beyond which TDN seemingly ceased to be limiting for N2 O production. The new emissions data for CH4 and N2 O presented here should help to develop more robust country level 'emission factors' for the quantification of national GHG inventory reporting. The impact of TDN on N2 O emissions suggests that soil nutrient status strongly impacts emissions, and therefore, policies which reduce N-fertilisation inputs might contribute to emissions mitigation from agricultural peat landscapes. However, the most important policy intervention for reducing emissions is one that reduces the conversion of peat swamp forest to agriculture on peatlands in the first place.

Net greenhouse gas balance of fibre wood plantation on peat in Indonesia

Tropical peatlands cycle and store large amounts of carbon in their soil and biomass1–5. Climate and land-use change alters greenhouse gas (GHG) fluxes of tropical peatlands, but the magnitude of these changes remains highly uncertain6–19. Here we measure net ecosystem exchanges of carbon dioxide, methane and soil nitrous oxide fluxes between October 2016 and May 2022 from Acacia crassicarpa plantation, degraded forest and intact forest within the same peat landscape, representing land-cover-change trajectories in Sumatra, Indonesia. This allows us to present a full plantation rotation GHG flux balance in a fibre wood plantation on peatland. We find that the Acacia plantation has lower GHG emissions than the degraded site with a similar average groundwater level (GWL), despite more intensive land use. The GHG emissions from the Acacia plantation over a full plantation rotation (35.2 ± 4.7 tCO2-eq ha−1 year−1, average ± standard deviation) were around two times higher than those from the intact forest (20.3 ± 3.7 tCO2-eq ha−1 year−1), but only half of the current Intergovernmental Panel on Climate Change (IPCC) Tier 1 emission factor (EF)20 for this land use. Our results can help to reduce the uncertainty in GHG emissions estimates, provide an estimate of the impact of land-use change on tropical peat and develop science-based peatland management practices as nature-based climate solutions.

De wording van een uniek verveningslandschap: de Molenpolder bij Westbroek

The creation of a unique peat landscape: the Molenpolder near Westbroek (province of Utrecht) In the Middle Ages most of the peatlands in the western part of the Netherlands were turned into agricultural land. In the Early Modern period large parts of this peatland were dug up in order to provide the upcoming towns and cities with fuel. This process of extraction – even below the ground water line by dredging –was still going on in some parts at the beginning of the 19th century when the land registry (Kadaster) was rolled out. This is the case in Molenpolder, a settlement north of the city of Utrecht, which today is a nature reserve. The strips of land (‘legakkers’) on which the peat was laid to dry and the peat holes in between are well preserved. The cadastral map offers a snapshot of how these strips were formed. The lord of the manor of Westbroek wanted to prevent all of his domain being turned into water and in 1790 started researching which part was best suited for peat extraction. A map of this research shows equally sized parcels which according to the Kadaster map (1832) were divided among the farmers in the vicinity, resulting in a mosaic of ownership. After the period of peat extraction, a process of hydrosere took place. The mosaic of ownership and therefore different levels of maintenance of each parcel resulted in a mosaic of different stages of ecological succession. After World War II a process of forestation started. Today the landscape is a mosaic of ponds, small pastures, marsh woodland, quake and thatch fields and other stages of ecological succession.

Faded landscape: unravelling peat initiation and lateral expansion at one of northwest Europe's largest bog remnants

Abstract. On the mainland of northwest Europe generally only remnants of former peat landscapes subsist. Due to the poor preservation of these landscapes, alternative approaches to reconstruct peat initiation and lateral expansion are needed compared to regions with intact peat cover. Here we aim (1) to find explanatory variables within a digital soil mapping approach that allow us to reconstruct the pattern of peat initiation and lateral expansion within (and potentially beyond) peat remnants, and (2) to reconstruct peat initiation ages and lateral expansion for one of the largest bog remnants of the northwest European mainland, Fochteloërveen. Basal radiocarbon dates were obtained from the peat remnant, which formed the basis for subsequent analyses. We investigated the relationship between peat initiation age and three potential covariates: (1) total thickness of organic deposits, (2) elevation of the Pleistocene mineral surface that underlies the organic deposits, and (3) a constructed variable representing groundwater-fed wetness based on elevation of the mineral surface and current hydraulic head. Significant relationships were found with covariates (1) and (3), which were then used for subsequent modelling. Our results indicate simultaneous peat initiation at several loci in Fochteloërveen during the Early Holocene and continuous lateral expansion until 900 cal BP. Lateral expansion accelerated between 5500–3500 cal BP. Our approach is spatially explicit (i.e. results in a map of peat initiation ages), and it allows for a quantitative evaluation of the prediction using the standard deviation and comparison of predictions with validation points. The applied method based on covariate (1) is only useful where remnant peat survived, whereas covariate (3) may ultimately be applied to reconstruct peat initiation ages and lateral peatland expansion beyond the limits of peat remnants.

Water pollution risks by smoldering fires in degraded peatlands

Climate change may increase the overall susceptibility of peatlands to fire. Smoldering fires in peatlands can cause substantial emissions of greenhouse gases. It is, however, less clear how smoldering affects the soil pore water quality. In this study, soil samples were collected from agricultural fen and disturbed bog study sites in Germany and Lithuania to quantify the effect of peat burning on pore water composition. The samples were air dried and smoldered under ignition temperature (approximately 200 °C) with different durations (0, 2, 5, and 10 h). Pore water samples were extracted from the soil to determine dissolved organic carbon (DOC) concentrations, dissolved organic matter (DOM) fractions, fluoride, extractable organically bound fluorine (EOF), and sulfate concentrations. The results showed that soil smoldering changes the peat pore water chemistry and that changes differ between fens and bogs. The smoldering duration is likewise influential. For fen grasslands, 2 and 5 h of smoldering of peat caused a >10-fold increase in DOC (up to 1600 mg L−1) and EOF concentrations. The fluoride (up to 60 mg L−1) and sulfate concentrations substantially exceeded WHO drinking water guidelines. In contrast, the temperature treatment decreased the DOC concentrations of samples from raised bogs by 90 %. The fluoride concentrations decreased, but sulfate concentrations increased after smoldering of the bog samples. DOC, fluoride, and sulfate concentrations of bogs varied significantly between the smoldering duration treatments. For all peat samples, the extracted DOM was dominated by humic-like substances before smoldering, but the fraction of low molecular weight substances increased after smoldering combustion. In conclusion, smoldering alters the biogeochemical processes in both peatland types and possibly impair the water quality of adjacent water resources especially in fen peat landscapes.

Making and Unmaking Territories with Plants in the Riverine Peat Landscape of Central Kalimantan

Central Kalimantan, located on the Indonesian side of Borneo, has often been described as a state frontier area where rapid changes take place in legal and administrative regimes and in the rules that govern access and ownership to land and nature. Today, frontier development includes state and non-state actors that bring natural resource projects aimed at producing long-term effects by engaging local people in the commodification of nature. Local people adopt and abandon these projects at a rapid pace due to changing conditions, policies, and natural hazards. I will explore commodification in terms of territorial projects and the spatial and temporal reordering of human-nature relations within the landscapes of Central Kalimantan. Linked to the territorial expansion of trees and plants, commodification challenges local environmental practices and forms of sociality. The paper argues that the commodification of nature and the territorial aspects of this bring new layers of complications and thus have unexpected effects on the lives of local populations. Keywords: frontier, commodification, plants, landscape, state-making, Kalimantan

Using legacy data to reconstruct the past? Rescue, rigour and reuse in peatland geochronology

AbstractThere is a growing interest in the rescue and reuse of data from past studies (so‐called legacy data). Data loss is alarming, especially where natural archives are under threat, such as peat deposits. Here we develop a workflow for reuse of legacy radiocarbon dates in peatland studies, including a rigorous quality assessment that can be tailored to specific research questions and study regions. A penalty is assigned to each date based on criteria that consider taphonomic quality (i.e., sample provenance) and dating quality (i.e., sample material and method used). The weights of quality criteria may be adjusted based on the research focus, and resulting confidence levels may be used in further analyses to ensure robustness of conclusions. We apply the proposed approach to a case study of a (former) peat landscape in the Netherlands, aiming to reconstruct the timing of peat initiation spatially. Our search yielded 313 radiocarbon dates from the 1950s to 2019. Based on the quality assessment, the dates—of highly diverse quality—were assigned to four confidence levels. Results indicate that peat initiation for the study area first peaked in the Late Glacial (~14,000 cal years BP), dropped during the Boreal (~9,500 cal years BP) and showed a second peak in the Subboreal (~4,500 cal years BP). We tentatively conclude that the earliest peak was mostly driven by climate (Bølling–Allerød interstadial), whereas the second was probably the result of Holocene sea level rise and related groundwater level rise in combination with climatic conditions (hypsithermal). Our study highlights the potential of legacy data for palaeogeographic reconstructions, as it is cost‐efficient and provides access to information no longer available in the field. However, data retrieval may be challenging, and reuse of data requires that basic information on location, elevation, stratigraphy, sample and laboratory analysis are documented irrespective of the original research aims.

Evaluating policy coherence: A case study of peatland forests on the Kampar Peninsula landscape, Indonesia

Conflicting policies relating to the management of multi-sectoral, multi-level and multi-actor forest uses often result in ineffective policy implementation. Methods for assessing policy coherence, however, are limited and often require an extensive evidence base which is not always available. In Indonesia, this has often led to conflicts between government agencies and other forest stakeholders. Businesses, NGOs and local communities struggle to comply with all of the conflicting or overlapping regulations that relate to the use of forested landscapes. Even if they succeed, the cost of implementation can be excessive. Improved methods for assessing policy coherence could assist governments and other stakeholders to navigate policy complexity and to avoid the potentially high costs of policies that are antagonistic to one another. We propose an audit of policy coherence at the landscape scale as a way of addressing this problem. We test this idea with an experimental policy audit on the Kampar Peninsula, a peat landscape in Pelalawan district, Riau Province, Indonesia. Indonesia has participated in the UN global peat initiative since 2015 and has created a peat protection policy to control the exploitation of peat with regulation No 57/2016. This regulation and the various instruments devolved from it has been a source of confusion and conflict among stakeholders. We applied commonly accepted performance auditing standards to assess the coherence, effectiveness and efficiency of regulations from other sectors and in different jurisdictions with the new peat regulation No 57/2016 and its derivatives. To aid our audit assessment, we overlaid radar and Landsat images to depict delineations of peat protection and cultivation zones according to different legislation. Our audit revealed incoherent mapping of peat protection zones on the Kampar Peninsula, which has led to ineffective and inefficient implementation of policies. We then propose three alternative protection and cultivation scenarios to that proposed by the government. Our results show that any of these alternative scenarios would provide a policy that is not only more coherent, but that also would result in more effective and efficient policy implementation. This policy audit method should have wide potential application for auditing best practice and policy effectiveness in complex landscapes across the globe and should have immediate application in helping to resolve the current issues on the Kampar Peninsular.

Agroforests, swiddening and livelihoods between restored peat domes and river: effects of the 2015 fire ban in Central Kalimantan (Indonesia)

If 150 years of continued use counts as a sustainability indicator, the river-bank agroforests in the peat landscapes of Central Kalimantan suggest solutions for current challenges. The 2015 fire season in Indonesian peatlands triggered a fire ban and peatland restoration response, prioritizing canal blocking and rewetting. However, sustainable livelihood options remain elusive. We report local ecological knowledge of soils and vegetation applied in land use choices in swiddens and agroforests in five Dayak Ngaju villages in Jabiren Raya and Kahayan Hilir subdistrict (Pulang Pisau, C. Kalimantan, Indonesia) on the banks of the Kahayan river and discuss impacts of fire-ban policies. Plots accessible from the river with no or shallow peat were traditionally preferred for swiddening, with various indicator plants and soil characteristics underpinning the choices. Without swiddening farmers depend on off-farm jobs and agroforests for income. More policy attention for non-peat riparian-zone agroforestry as part of peat landscape livelihood systems is warranted.

People-Centric Nature-Based Land Restoration through Agroforestry: A Typology

Restoration depends on purpose and context. At the core it entails innovation to halt ongoing and reverse past degradation. It aims for increased functionality, not necessarily recovering past system states. Location-specific interventions in social-ecological systems reducing proximate pressures, need to synergize with transforming generic drivers of unsustainable land use. After reviewing pantropical international research on forests, trees, and agroforestry, we developed an options-by-context typology. Four intensities of land restoration interact: R.I. Ecological intensification within a land use system, R.II. Recovery/regeneration, within a local social-ecological system, R.III. Reparation/recuperation, requiring a national policy context, R.IV. Remediation, requiring international support and investment. Relevant interventions start from core values of human identity while addressing five potential bottlenecks: Rights, Know-how, Markets (inputs, outputs, credit), Local Ecosystem Services (including water, agrobiodiversity, micro/mesoclimate) and Teleconnections (global climate change, biodiversity). Six stages of forest transition (from closed old-growth forest to open-field agriculture and re-treed (peri)urban landscapes) can contextualize interventions, with six special places: water towers, riparian zone and wetlands, peat landscapes, small islands and mangroves, transport infrastructure, and mining scars. The typology can help to link knowledge with action in people-centric restoration in which external stakeholders coinvest, reflecting shared responsibility for historical degradation and benefits from environmental stewardship.

An Integrated Landscape Approach for Socially Inclusive Peatland Restoration

Successful restoration and fire prevention in peat landscapes require full rewetting and permanent revegetation for optimal water retention. The ecological and socio-economic heterogeneity of these landscapes calls for integrated approaches based on participatory zonation and locally appropriate business models. Primary activities in deep-peat core zones are blocking of drainage canals and revegetation; in shallow-peat buffer zones, forestry and agroforestry on fully rewetted peat, aquaculture, and duck farming; while on surrounding non-peat mineral soils, more intensive tree plantations and agriculture. Community-oriented enterprises require private investment, including microfinance. Blended public and private investment is needed for core-zone restoration. Assuming restoration costs of USD 250-1,000 per ha on moderately drained peat, with emissions of 40tCO2/ha/year, carbon finance could pay for the cost of restoration in under 10 years if emissions are fully or largely abated. To stimulate investment in multiple peatland landscapes we propose a provincial ‘enabling platform’ to support participatory zoning, project design, and monitoring based on common standards and methodologies; technical assistance and incubation for project start-up; multi-stakeholder support for enabling policies, plans and institutions; strengthened finance mechanisms and bundled investments for large and small enterprises; and robust scientific support and knowledge exchange.

Peat People. On the Function and Context of Medieval Artificial Platforms in a Coastal Wetland, Eelder- and Peizermaden, the Netherlands

ABSTRACTLarge, artificial habitation platforms are widely distributed along the southern North Sea coasts. In this article, we will focus on the less known, small medieval platforms situated further inland, on the edge of the extensive peat bogs which until medieval times covered much of the lowlands of the Netherlands. We have confronted data from the area Eelder- and Peizermaden with existing models on the dynamics of human colonization and exploitation of North Sea coastal wetlands. The evidence from ‘peat terps’ seems to reflect distinct and successive land-use types or strategies that are associated with at least two colonization phases. Changes in land use are related to environmental changes that are largely human-induced. This is typical for coastal peat landscapes. Land-use patterns display spatio-temporal similarities as well as differences. The observed succession of land-use types and the associated material culture bear a strong resemblance to developments in the Assendelver polder a millennium before.

Структурно-функциональные особенности ландшафтов с активным термокарстом в северной тайге Западной Сибири

<p>In the article, the main results of the study of dissolved greenhouse gases (CO<sub>2</sub>, CH<sub>4</sub>), dissolved organic carbon (DOC) and colloidal trace elements-metals in surface and soil waters of hollows, depressions, permafrost subsidences are considered. These waters were sampled in areas with active and stable permafrost thawing in Western Siberia. It is found that these zones of active termokarst are mainly located on the slopes and the bottoms of the upper reaches of rivers, which drain the interfluve. Active thawing of flat mound bogs leads to the appearance of numerous hollows, depressions and thermokarst subsidences, especially on the border between forest and fens. This is related to the additional heat input from the flowing water and causing the thawing deep permafrost on the edges of ridges occupied by the forest. Increase in specific conductivity (S.C.) in the smallest water bodies and supra-permafrost water is accompanied by a significant increase in concentrations of DOC, P, K, Cu, Zn, Mo and Ba. It has been found that small hollows and subsidence (< 10 – 100 м²) are characterized by much higher concentrations of DOC and CO<sub>2</sub> (p < 0.05) in comparison with large depressions and thermokarst water bodies. There is also a decrease of CH<sub>4</sub> concentration with an increase in the size of water bodies (p < 0.05), despite the fact that the data dispersion reaches 3 orders in small (<100 – 300 m²) water bodies of the where located zones active termokarst landscape, concentrations of DOC, CO2 and CH4 are significantly higher (p <0.05) than in the previously studied water bodies formed under conditions of a stable state of permafrost in areas of Nojabrsk and Khanymey. Waters of the active thawed of permafrost peat landscapes are usually rich in oxygen (saturation in the range of 30 ≤ O2 ≤ 105 %) and approximately 0.5 unit’s pH more acidic than areas with a stable state of permafrost. Many major and trace elements show a statistically significant decrease in concentration from very small water bodies (< 10 m²) to larger thermokarst waters. By the results of carried out research we can say that in the landscapes with active termokarst there will be direct mobilization of soil water in the hydrological network (rivers and lakes) with a minimal transformation of the water composition within the catchment area.</p>

Warmer spring conditions increase annual methane emissions from a boreal peat landscape with sporadic permafrost

About a fifth of the global wetland methane emissions originate from boreal peatlands, which represent an important land cover type in boreal landscapes in the sporadic permafrost zone. There, rising air temperatures could lead to warmer spring and longer growing seasons, changing landscape methane emissions. To quantify the effect of warmer spring conditions on methane emissions of a boreal peat landscape in the sporadic permafrost zone of northwestern Canada, we analyzed four years (2013–2016) of methane fluxes measured with the eddy covariance technique and long-term (1951–2016) meteorological observations from a nearby climate station. In May, after snowmelt was complete, mean air temperatures were more than 2 °C warmer in 2013, 2015, and 2016 than in 2014. Mean growing season (May–August) air temperatures, in contrast, differed by less than 1 °C over the four years. Warmer May air temperatures caused earlier wetland soil warming, with temperatures rising from ~0 °C to >12 °C 25 to 40 days earlier and leading to ~6 °C warmer mean soil temperatures between May and June. However, from July to August, soil temperatures were similar among years. Mean May to August and annual methane emissions (6.4 g CH4 m−2 and 9.4 g CH4 m−2, respectively) of years with warmer spring (i.e. May) temperatures exceeded emissions during the cooler year by 20%–30% (4.5 g CH4 m−2 and 7.2 g CH4 m−2, respectively). Among years with warmer springs, growing season methane emissions varied little (±0.5 g CH4 m−2). The observed interannual differences are most likely caused by a strong soil temperature control on methane fluxes and large soil temperature differences during the spring. Thus, in a warming climate, methane emissions from waterlogged boreal peat landscapes at the southern limit of permafrost are likely to increase in response to more frequent occurrences of warm springs.

Detecting a moorland wildfire scar in the Peak District, UK, using synthetic aperture radar from ERS-2 and Envisat ASAR

Wildfires occur annually in UK moorland environments, especially in drought years. They can be severely damaging to the ecosystem when they burn deep into the peat, killing ground-nesting birds and releasing CO2 into the atmosphere. Synthetic aperture radar (SAR) was evaluated for detecting the 18 April 2003 Bleaklow wildfire scar (7.4 km2). SAR’s ability to penetrate cloud is advantageous in this inherently overcast area. SAR can provide fire scar boundary information which is otherwise labour intensive to collect in the field using a global positioning system (GPS). This article evaluates the potential of SAR intensity and InSAR coherence to detect a large peat moorland wildfire scar in the Peak District of northern England. A time-series of pre-fire and post-fire ERS-2 and advanced synthetic aperture radar (ASAR) Single Look Complex (SLC) data were pre-processed using SARScape 4.2 to produce georeferenced greyscale images. SAR intensity and InSAR coherence values were analysed against Coordinate Information on the Environment (CORINE) land‐cover classes and precipitation data. SAR intensity detected burnt peat well after a precipitation event and for previous fire events within the CORINE peat bog class. For the 18 April 2003 fire event, intensity increased to 0.84 dB post-fire inside the fire scar for the peat bog class. InSAR coherence peaked post-fire for moors and heathland and natural grassland classes inside the fire scar, but peat bog exposed from previous fires was less responsive. Overall, SAR was found to be effective for detecting the Bleaklow moorland wildfire scar and monitoring wildfire scar persistence in a degraded peat landscape up to 71 days later. Heavy precipitation amplified the SAR fire scar signal, with precipitation after wildfires being typical in UK moorlands. Further work is required to disentangle the effects of fire size, topography, and less generalized land‐cover classes on SAR intensity and InSAR coherence for detecting fire scars in degraded peat moorlands.

Population Density of Red Langurs in Sabangau Tropical Peat‐Swamp Forest, Central Kalimantan, Indonesia

Because of the large-scale destruction of Borneo's rainforests on mineral soils, tropical peat-swamp forests (TPSFs) are increasingly essential for conserving remnant biodiversity, particularly in the lowlands where the majority of habitat conversion has occurred. Consequently, effective strategies for biodiversity conservation are required, which rely on accurate population density and distribution estimates as a baseline. We sought to establish the first population density estimates of the endemic red langur (Presbytis rubicunda) in Sabangau TPSF, the largest remaining contiguous lowland forest-block on Borneo. Using Distance sampling principles, we conducted line transect surveys in two of Sabangau's three principle habitat sub-classes and calculated group density at 2.52 groups km⁻² (95% CI 1.56-4.08) in the mixed-swamp forest sub-class. Based on an average recorded group size of 6.95 individuals, population density was 17.51 ind km⁻², the second highest density recorded in this species. The accessible area of the tall-interior forest, however, was too disturbed to yield density estimates representative of the entire sub-class, and P. rubicunda was absent from the low-pole forest, likely as a result of the low availability of the species' preferred foods. This absence in 30% of Sabangau's total area indicates the importance of in situ population surveys at the habitat-specific level for accurately informing conservation strategies. We highlight the conservation value of TPSFs for P. rubicunda given the high population density and large areas remaining, and recommend 1) quantifying the response of P. rubicunda to the logging and burning of its habitats; 2) surveying degraded TPSFs for viable populations, and 3) effectively delineating TPSF sub-class boundaries from remote imagery to facilitate population estimates across the wider peat landscape, given the stark contrast in densities found across the habitat sub-classes of Sabangau.

Niche segregation in two closely related species of stickleback along a physiological axis: explaining multidecadal changes in fish distribution from iron-induced respiratory impairment.

Acute exposure to iron can be lethal to fish, but long-term sublethal impacts of iron require further study. Here we investigated whether the spatial and temporal distribution (1967–2004) of two closely related species of stickleback matched the spatial distribution of iron concentrations in the groundwater. We used the ‘Northern Peel region’, a historically iron-rich peat landscape in The Netherlands as a case study. This allowed us to test the hypothesis that niche segregation in two closely related species of stickleback occurred along a physiological axis. Patterns in stickleback occurrence were strongly associated with spatial patterns in iron concentrations before 1979: iron-rich grid cells were avoided by three-spined stickleback (Gasterosteus aculeatus, Linnaeus 1758) and preferred by nine-spined stickleback (Pungitius pungitius, [Linnaeus, 1758]). After 1979, the separation between both sticklebacks became weaker, corresponding to a decreased influence of local groundwater on stream water quality. The way both species changed their distribution in the field provides a strong indication that they differ in their susceptibility to iron-rich conditions. These observed differences correspond with differences in their respiration physiology, tolerance of poor oxygen conditions and overall life-history strategy documented in the literature. Our results exemplify how species can partition niche along a non-structural niche axis, such as sublethal iron-rich conditions. Other fish species may similarly segregate along concentration gradients in iron, while sublethal concentrations of other metals such as copper may similarly impact fish via respiratory impairment and reduced aerobic scope.Electronic supplementary materialThe online version of this article (doi:10.1007/s10452-012-9395-y) contains supplementary material, which is available to authorized users.

Wind-splash erosion of bare peat on UK upland moorlands

Peat is a common land surface material in many countries of the world and is particularly important in upland regions of the UK. Peat landscapes represent an important land use for hill farming, water management, and shooting, and are a globally scarce resource. Wind is a fundamental characteristic of upland environments in the UK and has long been recognised as a significant factor in peat erosion. This paper presents the first results of a project that aims to determine the significance of wind action in the erosion of upland peat. Wind erosion monitoring is being undertaken at Moor House in the North Pennines on a 3-ha area of relatively flat, sparsely vegetated peat. Measurements using arrays of passive horizontal mass flux gauges (fixed orientation vertical slot gauges), together with a vertical array of mass flux samplers (directional), provide estimates of sediment flux. A micrometeorological station records local wind speed (four heights), wind direction, rainfall, soil moisture, and temperature conditions. For 1999 and 2000, the annual horizontal net erosion flux is 0.46 and 0.48 t ha −1, respectively. Results of detailed monitoring over a 10-month period demonstrate that the peat sediment flux collected in windward- and leeward-oriented sediment traps on 10 separate occasions is between 3 and 12 times greater in the windward-facing traps. The concentration of peat with height decays rapidly and the majority of the peat is transported close to the ground surface. Above 0.3 m, very little peat is found. Significant horizontal fluxes of peat occur in both wet and dry periods. This is evaluated using the local micrometeorological data to try and predict sediment yields. Correlations among time-averaged friction velocity measurements, surface conditions, and sediment flux are complex. Event-based measurements, as opposed to cumulative sediment yields, are required to resolve this. These results quantify for the first time the significance of wind action in the erosion of peat in a UK upland environment.