Cutover Peatlands Research Articles

Ecological Groups of Coleoptera (Insecta) as Indicators of Habitat Transformation on Drained and Rewetted Peatlands: A Baseline Study from a Carbon Supersite, Kaliningrad, Russia.

A total of 281 coleopteran species from 41 families were recorded from different sites of an abandoned cut-over peatland designated as the Carbon Measurement Supersite in Kaliningrad Oblast. This beetle assemblage is considered a baseline (pre-impact) faunal assemblage for further investigations during the 'before-after' (BA) or 'before-after control-impact' (BACI) study on a peatland that is planned to be rewetted. The spontaneously revegetated peatland has a less specialised beetle assemblage than at an intact raised bog. Tyrphobiontic species are completely absent from the peatland, while some tyrphophiles (5.3% of the total beetle fauna) are still found as remnants of the former raised bog communities. The predominant coenotic coleopteran group is tyrphoneutral generalists from various non-bog habitats (72.9%). The species composition is associated with the vegetation structure of the disturbed peatland (fragmentary Sphagnum cover, lack of open habitats, and widespread birch coppice or tree stand), which does not correspond to that of a typical European raised bog. The sampled coleopteran assemblage is divided into several relative ecological groups, whose composition and peculiarities are discussed separately. Possible responses to the rewetting measurements in different coleopteran groups are predicted and briefly discussed. A complex assemblage of stenotopic peatland-specialised tyrphophiles (15 spp.) and the most abundant tyrphoneutral generalists (31 spp.) were assigned as indicators for the environmental monitoring of peatland development.

After-use of cutover peatland from the perspective of landowners: Future effects on the national greenhouse gas budget in Finland

Recently, increased attention has been drawn to the greenhouse gas emissions of the Land use, Land use Change and Forestry (LULUCF) sector. In the Finnish LULUCF sector, the soil-originated emissions from the after-use of cutover peatland have become a more relevant question. This is due to the rapid increase in the number of former peat-harvesting sites, caused by the decline in the combustion of energy peat due to its high CO2 emissions. We conducted a nationally representative survey to study which after-use options of cutover peatlands are preferred by landowners. Based on the preferred after-use options, we estimated their impact on the national greenhouse gas emissions in the Finnish regions in 2035, and what factors influence the landowners’ choice of after-use options. We found that the four most popular after-use options for landowners were afforestation (71%), agriculture (24%), production of wind and solar power (22%) and rewetting (18%) when the respondent chose the three most attractive options. However, there were clear regional differences in the preferred after-use options, which might lead, if realized, to different soil-originated emissions at the regional level. The preferred after-use options could produce emissions of 0.35 million tonnes of carbon dioxide equivalent a year (Mt CO2 eq y−1) by 2035 in Finland. Most of these emissions (30.1%) would come from South Ostrobothnia in western Finland, mainly due to the indicated high interest in agricultural after-use. Most landowners prefer financially profitable after-use options, such as forestry, agriculture, as well as wind and solar energy production in cutover peatlands. However, environmentally oriented landowners favour many kinds of actions to support biodiversity, carbon sequestration, and water protection in cutover peatlands. It is crucial that economic productivity and the greenhouse gas sinks of cutover peatlands be considered simultaneously to meet the climate targets of the LULUCF sector in Finland.

Аккумуляционные способности мохообразных нарушенных торфяников (на примере карбонового полигона в Калининградской области)

The paper provides original data on accumulation capabilities of bryophytes typical of peatland ecosystems with different degree of anthropogenic transformation occurring in the Kaliningrad Region of Russia. A key study area was the Vittgirrensky Peatland, abandoned after milled peat extraction in 1990s and designated as the Rossyanka Carbon Measurement Supersite in 2021. The accumulation of micro- and macroelements: Ca, Mn, Fe, Ni, Zn, Br, Rb, and Sr – was identified by means of X-ray fluorescence spectroscopy in 13 bryophyte species (Aulacomnium palustre, Campylopus introflexus, Polytrichum commune, P. strictum, Sphagnum capillifolium, S. centrale, S. cuspidatum, S. fuscum, S. magellanicum, S. riparium, S. squarrosum, S. teres) focusing on comparison with the reference species Pleurozium schreberi. The records of average element concentrations from the Vittgirrensky Peatland are shown to be distinctly lower than the regional background level. The accumulation of Mn, Ni, Br, Rb, and Sr varies significantly among disturbed and natural sites: the concentrations are comparable for Fe and Zn, while cut-over peatlands showed the level of Mn several times less than in undisturbed peat bogs. Aulacomnium palustre can be recommended for passive biomonitoring purposes on bog ecosystems as having most similar accumulation capability to the reference species Pleurozium schreberi that is widely recognized as indicator of atmospheric air pollution.

After Wildfires and Rewetting: Results of 15+ Years’ Monitoring of Vegetation and Environmental Factors in Cutover Peatland

On examples of n × 100 m2 permanent plots laid in 2005 on peatlands disturbed by quarrying and milling peat extraction in Meshchera National Park (central European Russia), changes in vegetation cover and environmental factors during self-revegetation, the impact of wildfire, and rewetting are considered. Peat extraction pits are overgrown with floating mats, on which mire, predominantly mesotrophic, vegetation is formed. Cofferdams with retained original mire vegetation contribute to the formation of a spatially diverse mire landscape, but they can also be prone to natural fires. The environmental conditions at the abandoned milled peat extraction sites do not favour natural overgrowth. The driest areas can remain with bare peat perennially. Such peatlands are the most frequent targets of wildfires, which have a severely negative impact and interrupt revegetation processes. Alien plant species emerge and disappear over time. To prevent wildfires and create conditions favourable for the restoration of mire vegetation, rewetting is required. With an average ground water level (GWL) during the growing season of −5 to +15 cm, mire vegetation can actively re-establish. Communities with near-aquatic and aquatic plants can form on flooded areas with GWL of +30. This generally contributes to both fire prevention and wetland diversity.

Field-scale compression of Sphagnum moss to improve water retention in a restored bog

The restoration and subsequent regeneration of Sphagnum moss on harvested peatlands can result in poor hydrological connectivity between the regenerated Sphagnum moss and the remnant cutover peat due to the formation of a capillary barrier that favours retention of water in the underlying cutover peat. In a restored cutover peatland in Québec, Canada, this resulted in a lower soil water content of the regenerated Sphagnum moss compared to a natural analogue, which may limit carbon sequestration potential. Previous work has shown it may take > 40 years for the regenerated moss layer to overcome this capillary barrier effect, however mechanical compression may provide a novel restoration technique to weaken the capillary barrier in restored peatlands. This study evaluated the effectiveness of field-based mechanical compression to ameliorate the capillary barrier effect and increase the moisture content in a restored cutover peatland. A section of restored Bois-des-Bel peatland was compressed using a John Deere 6430 series tractor in January 2016, followed by hydrological monitoring May-August. The Compressed site was compared to a nearby Uncompressed site, and a natural peatland ∼ 2 km away, to determine relative success of mechanical compression. The compression reduced moss height by 48%, increasing bulk density by 37% and reducing the proportion of macropores by 15% throughout the moss layer. Consequently, compression increased soil water retention and average soil moisture content at the Compressed site was consistently higher throughout the moss profile than in the Uncompressed site. This increased the resilience of the moss to drying, though the degree of increased resilience is unknown. Despite not having the same hydrophysical properties of the Natural site, the Compressed site was wetter than the Uncompressed site due to the lessening of the capillary barrier effect and moving the surface closer to the water table, thus decreasing the water stress of the regenerated Sphagnum carpet.

Получение посадочного материала Rubus arcticus L. методом клонального микроразмножения

The article presents the results of experimental studies on various propagation methods of the Arctic bramble in the Kostroma region. Industrial cultivation of forest berry plantations is a possible effective solution to the problem of low profitability of using nontimber forest products, reduction of the wild berries resources and their productivity and quality, and reclamation of cutover peatlands. It is advisable to use high-yield varietal planting material to create such plantations. Special attention is paid to propagation and production of healthy planting material using culture of plant cells and tissues. Data on sterilization of explants when introduced in vitro are given. The highest efficiency of sterilization was observed when using a chlorine-free eco-sterilizer (the plant survival rate on the MS nutrient medium was 90–93 %). The effect analysis of the passage number of regenerated plants on the multiplication factor of the Arctic bramble varieties was carried out. The optimal concentrations of cytokinins at the stage of micropropagation are shown. The largest number of the Arctic bramble roots was observed when adding 1.0 mg/L of Indole-3-butyric acid (IBA) and 0.5 mg/L of Ecogel to the nutrient medium. The technological and agrotechnical operations performed during the cultivation of planting material of forest berry plantations are considered. Data on the coefficients of vegetative propagation of plants and their resistance to diseases, yielding capacity, and recultivation of cutover peatlands are given. The best planting material of the Arctic bramble are ball-rooted seedlings. Sawdust and sphagnum were used in the cultivation of this berry on the peatland. The economic efficiency of its cultivation with the method of clonal micropropagation was 358.2 %. For citation: Makarov S.S., Tyak G.V., Kuznetsova I.B., Chudetsky A.I., Tsaregradskaya S.Yu. Producing Planting Material of Rubus arcticus L. by Clonal Micropropagation. Lesnoy Zhurnal [Russian Forestry Journal], 2021, no. 6, pp. 89–99. DOI: 10.37482/0536-1036-2021-6-89-99

Content of heavy metals (Zn, Pb, Cu and Cd) in peat and plants of cutover peatlands

Two peatlands in the central part of the Kirov region (Zengino and Karino) were investigated. During three field seasons, soil profiles were compiled and peat samples by layers were collected. The content of total and mobile forms of zinc, copper, lead and cadmium was determined by inversion voltammetry. The content of the studied elements does not exceed the average values for various soil types of the region. Development of the peatland led to a change in the content and redistribution of chemical elements in the newly formed profiles. The botanical composition of peat is substantially related to the content of chemical elements: the accumulation of metals in layers with prevalence of wood remains was revealed. Economic use leads to active mineralization of the top part of the remained peat mass. The profiles of developed peatlands are characterized by considerable fluctuations in the content of heavy metals both in different profiles and in different horizons of the same profile. Plants growing on dried peatlands accumulate low doses of the investigated metals that do not exceed standards of maximum allowance concentrations. Rosa majalis accumulate zinc, lead and cadmium in the least degree. The highest concentration of all four elements is found in the leaves of Salix caprea.

ПОЛУЧЕНИЕ ВЫСОКОКАЧЕСТВЕННОГО ПОСАДОЧНОГО МАТЕРИАЛА ЛЕСНЫХ ЯГОДНЫХ РАСТЕНИЙ МЕТОДОМ КЛОНАЛЬНОГО МИКРОРАЗМНОЖЕНИЯ ДЛЯ РЕКУЛЬТИВАЦИИ ВЫРАБОТАННЫХ ТОРФЯНИКОВ

The results of studies on the improvement of technology for producing highquality planting material of half-high blueberry and Arctic bramble by the method of clonal micropropagation are presented in the current paper. Creation of forest berry plantations in peat extraction areas allows reducing environmental damage and significantly increasing the efficiency of the timber industry. In recent decades, there has been an increasing interest in the creation of forest berry plantations on drained and cutover peatlands in Russia and other countries. It is necessary to use varietal planting material for the successful cultivation of forest berry plants on an industrial scale. Clonal micropropagation is the most effective of the vegetative methods for obtaining planting material, which allows receiving a huge amount of healthy planting material all year round in the conditions of a small laboratory area. Chloride-free ecosterilizer and bleaching agent based on sodium hypochlorite “Belizna” with an exposure of 15 and 20 min showed high efficiency in sterilization of explants of half-high blueberry and Arctic bramble. The highest viability of explants of the studied forest berry crops was observed when sterilized with a 0.1 % mercuric chloride solution and 15 min exposure, and its sharp decrease at 20 min exposure. At the stage of micropropagation, with an increase in the concentration of cytokinin 6-BAP from 0.5 to 1.0 mg/L on the nutrient Woody Plant Medium the number of shoots in regenerated plants of half-high blueberry (Northcountry and Northblue cultivars) and Arctic bramble (Anna and Sofia cultivars) increased. The effect of the concentration of IBA-derived auxin on the number and length of roots of regenerated plants was observed at the in vitro rooting stage.

Biogas and combustion potential of fresh reed canary grass grown on cutover peatland

(1) In Finland, in recent years, the combustion of dry reed canary grass (RCG, Phalaris arundinacea) grown intensively on cutover peatlands, has decreased markedly. We therefore made experiments in two areas to assess the alternative of using freshly harvested RCG grown for biogas production on cutover peatland. We measured both biogas production and combustion energy release. (2) The experiments show that the RCG biomass yields in total solids (TS) in both areas, with two cuts a year, were surprisingly small (yields of 2.7 and 4.2 Mg ha-1 [1 Mg ha-1 = 100 g m-2 ]); having biogas and combustion potentials, on the two areas, of 277–348 dm3 kg-1 VS (volatile solids) and 14.8–16.3 MJ kg-1 TS, and 11.8–21.9 MWh ha-1 in combustion. (3) Fresh RCG may produce larger biomass yields if cut several times a year, together with lower lignin proportion, and better suitability for biogas production compared with spring harvested dry RCG. (4) For cutover peatlands there are several after-use possibilities, however, with different benefits and challenges. For example, peat soil emissions may be affected during the after-use period, and this should be considered when planning the use of cutover peatlands.

Peculiarities of the growth of virgin blueberry plants on the developed peat deposit with the application of mineral and microbial fertilizers

The results of comparative study of current increment of vegetative sphere yearling and biennial of plants of a half-highbush blueberry Northland and Denise Blue at fertilizer application NPK-compound (N16P16K16) and of some microbial specimen – a liquid product of MaKloR in concentration of 10 and 50 % in test crop on recultivated cutover peatlands in article are resulted. It is positioned that tested agricultural methods have rendered the expressed promoting effect on formation of a current increment of vegetative sphere of plants of a blueberry. In the first year of fertilization the least efficacy is positioned for a variant with N16P16K16 which conceded to a drug of MaKloR in 1.1–1.5 times. Its productivity increased with concentration augmentation in 1.2–1.4 times, depending on a varietal accessory of plants and phylum of shoots. In the absence of varietal differences in degree of positive influence of microbial fertilizing of MaKloR on development of vegetative propagules, efficacy of its action, as well as N16P16K16, on development of generative propagules, in variety Denise Blue exceeded for kind Northland in 4.2–4.8 times.Positive influence of mineral and microbial fertilizing’s on a current increment of vegetative sphere of biennial plants of both variety of a blueberry essentially conceded to that annotinous, against conservation of its progressing magnification in process of strengthening of microbial fertilising of MaKloR. Thus productivity of action N16P16K16 on development of propagules in variety Northland, depending on their phylum, exceeded that microbial fertilising of MaKloR in 1.2–1.9 times, at variety Denise Blue – in 1.3–2.6 times. It is shown that against absence of the expressed varietal distinctions in degree of stimulating influence of fertilizings on development of vegetative shoots, efficacy of their action on development of generative shoots, unlike annual plants, at kind Denise Blue conceded that for kind Northland in 1.7–2.3 times.

Effect of foliar fertilization of microelements on highbush blueberry (Vaccinium corumbosum L.) nutrient status and yield components in cutover peatlands

Effect of foliar fertilization of microelements on highbush blueberry (Vaccinium corumbosum L.) nutrient status and yield components in cutover peatlands

Short-term effects of fen peatland restoration through the moss layer transfer technique on the soil CO2 and CH4 efflux

Northern peatlands store approximately one third of the global soil carbon (C) stocks. Peat extraction for horticulture changes C fluxes turning these soils from sinks into large sources of C emitted to the atmosphere as greenhouse gases. Restoring hydrological conditions may not be enough for returning the C sink function of these ecosystems and a recovery of the original Sphagnum-dominated vegetation cover could be necessary. Here we tested the effects of the moss layer-transfer technique (MLTT) on the CO2 and CH4 fluxes three years after restoration of a minerotrophic cutover peatland in Quebec, Canada. Gas emissions were compared to nearby undisturbed plots, and plots with restored hydrology but without vegetation transfer. The main drivers for the observed emissions were inferred from the relationships with relevant environmental variables (vegetation cover, water table depth and temperature). Restoration of the extracted minerotrophic fen through the MLTT produced significant changes in the exchange of CO2, bringing these fluxes closer to undisturbed plots than plots with restored hydrology only, which remained C sources throughout the study. Methane emissions were generally low across all the restored plots and far from natural levels, with only a slight increase at the MLTT restored plots observed during the third year. Even though the MLTT failed to recover the original bryophyte-dominated vegetation, the observed changes in the emissions of CO2 and CH4 at the restored plots were strongly associated with changes in vegetation cover (i.e. increase in vascular plants), supporting the use of this restoration technique to recover the C sink function of harvested minerotrophic peatlands.

The effect of compression on Sphagnum hydrophysical properties: Implications for increasing hydrological connectivity in restored cutover peatlands

AbstractSphagnum moss, a dominant peat‐forming species in northern peatlands, relies on capillary rise to sustain metabolic activities. However, in restored peatlands, a capillary barrier resulting from distinctly different pore‐size distributions in the degraded remnant cutover peat and regenerated Sphagnum moss limits capillary rise. Space‐for‐time analogues suggest it could take >40 years for decomposition and degradation of the moss profile to overcome this capillary barrier effect. This paper explores the feasibility of mechanical compression to ameliorate the capillary barrier effect and accelerate the return of ecohydrological function in restored Sphagnum moss. Seven reference cores (10 × 20 cm) and 29 samples (10 × 5 cm) representing various depths from surface (0–5 cm, n = 9; 5–10 cm, n = 9; 10–15 cm, n = 7; 15–20 cm, n = 4) were tested in a laboratory setting to analyse pre‐compression and post‐compression water retention‐unsaturated hydraulic conductivity relationships, proportion of macropores, and other hydrophysical parameters. Post‐compression, reference core moss height (originally 20 cm) decreased by 5.5 ± 1.2 cm, and sample bulk density increased, while porosity decreased (Wilcoxon signed rank test, p < 0.01). Increased water retention and subsequent increase in unsaturated hydraulic conductivity post‐compression was a result of a decrease in macropores (diameter > 75 μm). Simulation results with Hydrus‐1D indicate that the post‐compression moss profile was better suited to maintain pressure heads above critical values for photosynthesis. These findings suggest that mechanical compression may be used to ameliorate the capillary barrier effect in restored cutover peatlands; however, field scale studies are required.

New locations of rare vascular plant species on cut-over peat lands (on the example of Kirov Region)

The paper presents the investigation data of 6 cut-over peat lands in central area of Kirov Region (on the example of Zuev, Orichev, Slobod, Kirov and Chepez areas). The authors found the new locations of 10 rare plant species enlisted in the regional Red Book and species that have limited distribution in a region or have narrow ecological range (Gymnadenia conopsea, Dactylorhiza fuchsii, Epipactis helleborine, Epipactis atrorubens, Platanthera bifolia, Trichophorum alpinum, Botrychium multifidum, Dryopteris cristata, Thelipteris palustris, Huperzia selago). They also describe the process of phytocoenoses. The study shows the development of new typical boggy plant societies as a result of secondary bogging (on the example of Trichophorum alpinum, Drosera rotundifolia, Carex nigra, Eriophorum vaginatum, Parnassia palustris). The paper estimates the state of rare species populations. The authors analyze the ability of the species to inhabit artificial landscapes and anthropogenically modified phytocoenoses. That shows an explerent component of ecological-phytocoenotic strategy. Secondary boggy landscapes can play the role of refugiums for the species which habitats were lost due to industrial impact.

Plant rhizosphere oxidation reduces methane production and emission in rewetted peatlands

The global loss of peatlands, by drainage or peat extraction, has encouraged measures to restore these ecosystems and their function as carbon sinks. However, there is a potential of high emissions of the potent greenhouse gas CH4 from restored peatlands. Vascular plants, which often dominate restored sites, play a key role in determining the amount of emitted CH4: The plants can either fuel methanogenesis by supplying labile carbon or attenuate methanogenesis by transferring oxygen into the rhizosphere. To quantify the net effect of these counteracting processes, we tested in a two-pronged approach CH4 production, emission, and the underlying processes in (1.) monoliths of three different restored cutover peatlands and in (2.) mesocosms with Eriophorum vaginatum, E. angustifolium and Juncus effusus versus controls with Sphagna and bare peat. Despite waterlogged, and thus persisting anoxic conditions, concentrations of dissolved CH4 remained close to zero in all tested monoliths. We ascribe this finding to two factors: The poor decomposability of the peat material, as determined in anoxic incubations, and the availability of alternative electron acceptors that sustained anaerobic respiration and competitively suppressed methanogenesis. While inorganic electron acceptor pools were small and rapidly diminished, dissolved organic matter provided constant electron acceptor capacity, indicating that reducible moieties in the organic matter were continuously re-oxidized in the rhizosphere of all tested vascular plant species. This continuous re-oxidation of the dissolved organic matter correlated with plant growth rates (R2 = 0.6–0.8), suggesting that supply of oxygen through the aerenchyma of plant roots regenerated electron acceptor capacity in the rhizosphere. Vascular plants may have differential effects on the net ecosystem exchange, however, our findings suggest that CH4 concentrations and emissions may remain low in restored cutover peatlands for months to years. Thus, waterlogging and vascular plant cover of degraded cutover peatlands does not necessarily create hot-spots of CH4 emissions.

The impact of a black spruce (Picea mariana) plantation on carbon exchange in a cutover peatland in Western Canada

Northern peatlands are sinks for atmospheric carbon (C), but peat extraction converts these ecosystems to C sources. Due to a dry regional climate, undisturbed bog peatlands in western Canada often have a tree cover of Picea mariana (Mill.) B.S.P. Thus, a coniferous forest plantation may be an appropriate land use for cutover peatlands. This study determined the effect of a 7-year-old P. mariana plantation on C balance of a cutover peatland. We measured C stored in P. mariana biomass and carbon dioxide (CO2) and methane (CH4) fluxes from bare peat at each of four fertilizer doses. Carbon stored in biomass of Betula papyrifera (Marsh.) that had spontaneously colonized the postfertilized site was also determined. Given that the water table remained very deep and that the sphagnum moss – ericaceous shrub peat-accumulating vegetation was not present, the site remained a source of C when only the planted P. mariana trees were considered, primarily in the form of CO2 emissions by soil respiration. However, C accumulation in trees, including B. papyrifera biomass, resulted in a net C sink in fertilized plots. Results from this study indicate that tree plantations on cutover peatland may be a suitable land-management strategy on sites difficult to effectively rewet.

Rewetting degraded peatlands for climate and biodiversity benefits: Results from two raised bogs

Globally, peatlands are under threat from a range of land use related factors that have a significant impact on the provision of ecosystem services, such as biodiversity and carbon (C) sequestration/storage. In Ireland, approximately 84% of raised bogs (a priority habitat listed in Annex I of the EU Habitats Directive) have been affected by peat extraction. While restoration implies the return of ecosystem services that were characteristic of the pre-disturbed ecosystem, achieving this goal is often a challenge in degraded peatlands as post-drainage conditions vary considerably between sites. Here, we present multi-year greenhouse gas (GHG) and vegetation dynamics data from two former raised bogs in Ireland that were drained and either industrially extracted (milled) or cut on the margins for domestic use and subsequently rewetted (with no further management). When upscaled to the ecosystem level, the rewetted nutrient poor domestic cutover peatland was a net sink of carbon dioxide (CO2) (−49 ± 66 g C m−2 yr−1) and a source of methane (CH4) (19.7 ± 5 g C m−2 yr−1), while the nutrient rich industrial cutaway was a net source of CO2 (0.66 ± 168 g C m−2 yr−1) and CH4 (5.0 ± 2.2 g C m−2 yr−1). The rewetted domestic cutover site exhibited the expected range of micro-habitats and species composition found in natural (non-degraded) counterparts. In contrast, despite successful rewetting, the industrially extracted peatland did not exhibit typical raised bog flora. This study demonstrated that environmental and management variables can influence species composition and, therefore, the regeneration of species typical of natural sites, and has highlighted the climate benefits from rewetting degraded peatlands in terms of reduced GHG emissions. However, rewetting of degraded peatlands is a major challenge and in some cases reintroduction of bryophytes typical of natural raised bogs may be more difficult than the achievement of proper GHG emission savings.

Recovery of methane turnover and the associated microbial communities in restored cutover peatlands is strongly linked with increasing Sphagnum abundance

Vegetation succession is known to affect carbon-cycling patterns of recovering cutover peatlands, displayed as shifts in emissions of the greenhouse gases CO2 and CH4. However, the related plant-microbe interactions are still poorly understood. We aimed to link the recovery of the organisms responsible for CH4 turnover, the methanogens and the methanotrophs, to the re-vegetation related compositional changes of three functional plant types (Sphagna, sedges and shrubs). In peat layers, the Sphagnum coverage was the most influential factor for the activity, abundance and community structures of both these microbial groups, demonstrating a succession pattern towards a pristine stage. Analysis of mcrA and pmoA genes revealed Methanoregulaceae and Methylocystis as the most dominant methanogens and methanotrophs, respectively. The relatively fast recovery of both CH4 production and oxidation in the peat layers supports earlier flux based results from these same fen-type peatland sites. In contrast to peat, CH4 oxidation in living Sphagnum mosses appeared to be independent of vegetation succession as CH4 oxidation potential was similar throughout the succession stages. This indicated that Sphagnum may be a valuable CH4 biofilter especially in the early re-vegetation stages when the oxidation in the peat has not yet recovered. Therefore, we recommend Sphagnum transplantation as a tool for climate friendly peatland restoration with faster recovery of the carbon sink function and altered CH4 emissions.

Fertilization stimulate root production in cloudberry rhizomes transplanted in a cutover peatland

Cloudberry has good economic potential for Canada, but crop practices must be improved before commercial production can be established. Transplants usually consist of rhizome segments collected in natural populations; however, the very low root density of these transplants might partly explain their initial slow growth and high mortality. The objective of this study was to determine the effects of mineral fertilization and auxin applications on root initiation and elongation. Three N–P–K fertilization treatments were applied at the planting of bare rhizomes in peatlands, while auxin applications were tested in both greenhouse and field experiments. Roots of fertilized plants were two to four times longer and more numerous than those of control plants after one complete growing season but fertilization did not lead to early rooting. Rhizome segments produced new shoots before investing in root production, suggesting that rhizome carbohydrate reserves are not sufficient to allow both the shoot and root to be produced at the same time. Auxin applications to the rhizomes incurred high mortality and did not stimulate root production in both the field and greenhouse experiments. We conclude that fertilizers applied at planting can improve cloudberry initial survival rate, rooting, and early shoot growth, which could eventually lead to improved plant cover and fruit yield.

Soil water dynamics and hydrophysical properties of regenerating Sphagnum layers in a cutover peatland

AbstractThe physical and hydrological conditions in extracted peatlands often act as barriers to the regeneration of the keystone peat‐forming genus Sphagnum. Although previous work has suggested that Sphagnum mosses regenerating on cutover peat surfaces quickly become vulnerable to water stress as the thickness of the regenerated layer increases, uncertainties regarding the storage and transmission properties of this layer and how these might evolve over time have made this assertion difficult to evaluate. This study investigates the hydrophysical properties and hydrological behaviour of regenerating Sphagnum layers ranging from 3 to 43 years in age using both field and laboratory methods. The >40‐year‐old regenerated layers had significantly (p < 0.001) higher bulk density and retention capacity in the 5‐cm‐thick basal layer directly overlying the cutover peat than the newer (<10 year old) regenerated layers. Capillarity was a much stronger control on surficial water content (θ) than precipitation, which was poorly retained in the Sphagnum canopy, suggesting that regulation of water table position is an effective method of controlling θ as a means of optimizing productivity. In general, the θ sustained at a given water table position decreased as regenerated layer thickness increased. Analysis of water table position relative to the former cutover peat surface in different areas of the site suggests that the soil water dynamics of the >40‐year‐old regenerated layers may be becoming increasingly similar to those of a natural bog peatland. Copyright © 2015 John Wiley & Sons, Ltd.