Cloudberry cultivation in cutover peatland : improved growth on less decomposed peat.

La culture de la chicouté est sérieusement évaluée comme une option de réhabilitation des tourbières après récolte de la tourbe à des fins horticoles. Outre le gain en termes de valeur écologique et économique de ces sites, la culture de la chicouté pourrait augmenter le rendement en fruits et faciliter la récolte des fruits par rapport à la récolte en tourbières naturelles. Des études antérieures ont montré une croissance initiale lente qui a été provisoirement attribuée aux caractéristiques du substrat. Des expériences sur le terrain et en serres ont donc été mises en place pour mieux caractériser l'effet de différents substrats combinée aux techniques de restauration, sur la croissance des clones mâles et femelles. La chicouté a présenté une meilleure croissance en tourbe fibrique moins décomposée (H1–H3) qu'en tourbe mésique plus décomposée. La restauration devrait donc précéder la mise en culture de la chicouté de quelques années, afin de planter les rhizomes dans la couche de tourbe fibrique nouvellement accumulée. Les clones mâles produisent des feuilles plus grandes et plus de ramets par rhizome que les clones femelles en conditions communes de croissance. Les différences observées entre les sexes sont donc d'ordre génétique plutôt qu'environnemental. De plus, nous avons observé que les clones semblent particulièrement sensibles à la présence d'aluminium. En conclusion, le niveau de décomposition de la tourbe apparaît comme un des facteurs déterminant le succès de plantations de chicouté.Cloudberry cultivation is being seriously considered as a rehabilitation option for industrial peatlands after horticultural peat extraction has ceased. Besides increasing the ecological and economic values of these sites, cloudberry cultivation could improve fruit yield and facilitate fruit harvesting compared to picking in natural peatlands. Previous studies reported slow establishment that was tentatively associated with substrate characteristics. Field and greenhouse experiments were thus conducted to better characterize the impact of different peat substrates in combination with restoration techniques on the growth of male and female clones. Cloudberry grew much better in less-decomposed fibric peat (H1-H3) than in more-decomposed mesic peat. Restoring the moss layer of the former peat field would thus need to precede cloudberry planting by a few years, in order to plant the rhizomes in a newly formed fibric peat layer. Male clones produced larger leaves and more ramets per rhizome than female clones under common greenhouse conditions, which indicated that differences between sexes are most likely genetic rather than environmental. Furthermore, we found cloudberry clones may be very sensitive to aluminium toxicity. In conclusion, the degree of peat decomposition appears to be one of the key factors determining the success of cloudberry plantations

Above-Ground Net Primary Production from Vascular Plants Shifts the Balance Towards Organic Matter Accumulation in Restored Sphagnum Bogs

Abstract The organic matter accumulation potential of a restored bog was estimated over 2 years as a balance between losses to decomposition and inputs through aboveground net primary productivity (AGNPP) in five microhabitats of increasing complexity (relating to the moss carpet thickness and the number of vegetation functional groups). Decomposition and accumulation rates variations were hypothesized to lead to higher organic matter accumulation potential in the more complex micro-habitats. In general, for a given litter type, the mass losses and decomposition rates were rather homogeneous between microhabitats, but, they were correlated to the cover of particular species: Eriophorum vaginatum with slower decomposition rates, and Ledum groendlandicum or Kalmia angustifolia with higher rates. Therefore, the abundance of some peatland species, rather than the habitat complexity itself, was a driver of decomposition rates. While the Sphagnum AGNPP did not compensate for decomposition losses, the organic matter accumulation potential was tipped towards a sink (positive) by the contribution of vascular species to the AGNPP. The organic matter accumulation potentials are much improved by the presence of Sphagnum, but from a restoration perspective, promoting the growth of vascular peatland species might also be a key to achieving a positive balance of organic matter accumulation

Editorial : Observing, Modeling and Understanding Processes in Natural and Managed Peatlands

Non peer reviewe

Response of vegetation and net ecosystem carbon dioxide exchange at different peatland microforms following water table drawdown

This is the peer reviewed version of the following article: Strack, M., Waller, M.F. and Waddington, J.M. 2006. Sedge succession and peatland methane dynamics: A potential feedback to climate change. Ecosystems, 9, 278-287., which has been published in final form at https://doi.org/10.1029/2005JG000145. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Use of Self-Archived Versions. This article may not be enhanced, enriched or otherwise transformed into a derivative work, without express permission from Wiley or by statutory rights under applicable legislation. Copyright notices must not be removed, obscured or modified. The article must be linked to Wiley’s version of record on Wiley Online Library and any embedding, framing or otherwise making available the article or pages thereof by third parties from platforms, services and websites other than Wiley Online Library must be prohibited.Northern peatlands are significant stocks of terrestrial soil carbon, and it has been predicted that warmer temperatures and lower water tables resulting from climate change will convert these ecosystems into sources for atmospheric carbon dioxide (CO2). However, these predictions do not consider the potential for hydrologically induced ecological succession or the spatial variability of carbon accumulation rates between different microforms in peatlands. To address these issues, the vegetation community was described, and the rates of gross ecosystem photosynthesis (GEP), ecosystem respiration (Rtot) and net ecosystem CO2 exchange were determined along poor fen microtopographic gradients at a control site and at a site which experienced a water table drawdown of 20 cm 8 years prior to the study (drained). Sampling plots within these sites were classified as microforms of hummocks, lawns, or hollows. The coverage of Sphagnum moss declined on drained hummocks, drained lawns were invaded by sedges, and hollows shifted from open water plots at the control site to Sphagnum-dominated plots with sparse vascular plant cover at the drained site. As a result, Rtot was significantly greater at the drained site at all microforms while maximum rates of GEP declined at drained hummocks and were enhanced at drained lawns and hollows compared to similar control microforms. These results suggest that predictions about the response of northern peatland carbon exchange to climate change must consider the interaction between ecology and hydrology and the differential responses of microforms related to their initial ecohydrological conditions.This research was funded by NSERC (Canada) and Canadian Foundation for Climate and Atmospheric Science (CFCAS) grants to J.M.W., NSERC Julie Payette and CGS scholarships to M.S., and a postdoctoral grant from the Academy of Finland (project 12328) and from the Faculty des Sciences de l'Agriculture et de l'Alimentation, Université Laval, to E.T

Effect of Plant Functional Type on Methane Dynamics in a Restored Minerotrophic Peatland

This is a post-peer-review, pre-copyedit version of an article published in [insert journal title]. The final authenticated version is available online at: https://doi.org/10.1007/s11104-016-2999-6Background and Aims: Peatland methane (CH4) fluxes may vary between plant types; however, in mixed communities, the specific role of each species is difficult to distinguish. The goal of this study was to determine the individual and interacting effect of moss, graminoid and shrub plant functional types on CH4 dynamics of experimentally planted plots in a rewetted minerotrophic peatland. Methods We measured CH4 flux, pore water CH4 concentration and CH4 production and oxidation potential in pure stands of reintroduced Tomenthypnum nitens (Hedw.) Loeske, Carex aquatilis Wahlenb, or Myrica gale L., as well as mixtures of T. nitens + C. aquatilis and T. nitens + M. gale. Methane flux was also measured on bare peat plots. ResultsThe presence of both the graminoid C. aquatilis and the shrub M. gale resulted in the highest CH4 production potential in near surface peat (10 cm). The presence of moss (T. nitens) and C. aquatilis significantly increased CH4 oxidation potential. Water table position was a significant control on CH4 flux, but the presence of C. aquatilis maintained higher flux even at dry plots. Plots including C. aquatilis had significantly lower pore water CH4 concentration at 30 cm depth, likely reflecting CH4 oxidation and transport. Conclusions Management of restored sites aiming to reduce CH4 flux should focus on hydrology, i.e. water table position. The presence of graminoids enhances CH4 flux, while moss presence may result in lower CH4 emission

Ecological restoration of rich fens in Europe and North America: from trial and error to an evidence-based approach

Fens represent a large array of ecosystem services, including the highest biodiversity found among wetlands, hydrological services, water purification and carbon sequestration. Land use change and strong drainage has severely damaged or annihilated these services in many parts of North America and Europe, which urges the need of restoration plans at the landscape level. We review the major constraints for the restoration of rich fens and fen water bodies in agricultural areas in Europe and disturbed landscapes in North America: 1) habitat quality problems: drought, eutrophication, acidification, and toxicity, 2) recolonization problems: species pools, ecosystem fragmentation and connectivity, genetic variability, invasive species, and provide possible solutions. We discuss both positive and negative consequences of restoration measures, and their causes. The restoration of wetland ecosystem functioning and services has, for a long time, been based on a trial and error approach. By presenting research and practice on the restoration of rich fen ecosystems within agricultural areas, we demonstrate the importance of biogeochemical and ecological knowledge at different spatial scales for the management and restoration of biodiversity, water quality, carbon sequestration and other ecosystem services, especially in a changing climate. We define target processes that enable scientists, nature managers, water managers and policy makers to choose between different measures and to predict restoration prospects for different types of deteriorated fens and their starting conditions