Browsing by Subject "PEATLANDS"

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  • Ngau, Laura, D.; Fong, Sim, S.; Khoon, Kho L.; Rumpang, Elisa; Vasander, Harri; Jauhiainen, Jyrki; Yrjälä, Kim; Silvennoinen, Hanna (2022)
    Water table conditions in drained peatlands affect peat decomposition, fluvial carbon and greenhouse gas emissions, and plant growth in oil palm plantations. This study illustrates the spatial heterogeneity of soil moisture profiles in cultivated tropical peat under oil palm plantation and uncultivated secondary forest, using maps. At a study plot under each land use the geographical coordinates of sampling points, tree locations and other features were recorded. Peat soil samples were taken at depths of 0–50 cm, 50–100 cm, 100–150 cm and 150–200 cm, and their moisture contents were determined. Overall, soil moisture content was higher in secondary forest than in oil palm plantation due to land management activities such as drainage and peat compaction in the latter. Significant differences were observed between the topsoil (0–50 cm) and deeper soil layers under both land uses. Soil moisture maps of the study plots interpolated using geographical information system (GIS) software were used to visualise the spatial distributions of moisture content in soil layers at different depths (0–50 cm, 50–100 cm, 100–150 cm, 150–200 cm). Moisture content in the 0–50 cm soil layer appeared to be inversely related to elevation, but the correlation was not statistically significant. On the other hand, there was a significant positive correlation between soil moisture content and the diameters of oil palm trunks. Palm trees with negative growth of trunk diameter were mostly located in subplots which were relatively dry and/or located near drains. The results of this study indicate that soil moisture mapping using GIS could be a useful tool in improving the management of peatland to promote oil palm growth.
  • Tsuruta, Aki; Aalto, Tuula; Backman, Leif; Krol, Maarten C.; Peters, Wouter; Lienert, Sebastian; Joos, Fortunat; Miller, Paul A.; Zhang, Wenxin; Laurila, Tuomas; Hatakka, Juha; Leskinen, Ari; Lehtinen, Kari E. J.; Peltola, Olli; Vesala, Timo; Levula, Janne; Dlugokencky, Ed; Heimann, Martin; Kozlova, Elena; Aurela, Mika; Lohila, Annalea; Kauhaniemi, Mari; Gomez-Pelaez, Angel J. (2019)
    We estimated the CH4 budget in Finland for 2004?2014 using the CTE-CH4 data assimilation system with an extended atmospheric CH4 observation network of seven sites from Finland to surrounding regions (Hyytiälä, Kj?lnes, Kumpula, Pallas, Puijo, Sodankylä, and Utö). The estimated average annual total emission for Finland is 0.6?±?0.5 Tg CH4 yr?1. Sensitivity experiments show that the posterior biospheric emission estimates for Finland are between 0.3 and 0.9 Tg CH4 yr?1, which lies between the LPX-Bern-DYPTOP (0.2 Tg CH4 yr?1) and LPJG-WHyMe (2.2 Tg CH4 yr?1) process-based model estimates. For anthropogenic emissions, we found that the EDGAR v4.2 FT2010 inventory (0.4 Tg CH4 yr?1) is likely to overestimate emissions in southernmost Finland, but the extent of overestimation and possible relocation of emissions are difficult to derive from the current observation network. The posterior emission estimates were especially reliant on prior information in central Finland. However, based on analysis of posterior atmospheric CH4, we found that the anthropogenic emission distribution based on a national inventory is more reliable than the one based on EDGAR v4.2 FT2010. The contribution of total emissions in Finland to global total emissions is only about 0.13%, and the derived total emissions in Finland showed no trend during 2004?2014. The model using optimized emissions was able to reproduce observed atmospheric CH4 at the sites in Finland and surrounding regions fairly well (correlation > 0.75, bias
  • Jauhiainen, J.; Silvennoinen, H.; Hamalainen, R.; Kusin, K.; Limin, S.; Raison, R. J.; Vasander, H. (2012)
  • Paoli, Gary D.; Carlson, Kimberly M.; Hooijer, Aljosja; Page, Susan E.; Curran, Lisa M.; Wells, Philip L.; Morrison, Ross; Jauhiainen, Jyrki; Pittman, Alice M.; Gilbert, David; Lawrence, Deborah (2011)
  • Pang, Yuwen; Huang, Yuxin; He, Li; Zhou, Yinying; Sui, Jun; Xu, Junfeng (2021)
    Boreal peatlands, of which Sphagnum bogs are one of the main types, play essential roles in the terrestrial soil carbon pool. Vegetation phenology is a sensitive indicator that reveals the underlying processes as well as responses to climate change, while currently there remain knowledge gaps in exploring and monitoring the longterm bog vegetation phenology due to insufficient remote sensing application experiences. In this study, we investigated three remotely sensed vegetation phenological parameters, the start of growing season (SOS), the end of growing season (EOS), and the length of growing season (LOS) in two bogs located in norther China by using double-logistic reconstructed MOD13Q1-EVI from 2001 to 2018, which were evaluated by the flux phenology. Also combing with meteorological data to detect interactions between vegetation phenology and climate change. The results showed that remotely sensed EOS had 8-day time lags with flux phenological date, while that outperformed SOS. Bog vegetation generally with a life pattern of SOS at the 108th day of year (doy) and EOS at the 328th doy, though the life cycle of individual vegetation groups varies among different vegetation communities. There was no significant delayed (or extended) trend in each phenological features in bogs. Precipitation and minimum temperature (monthly and annual) were the driving forces for bog vegetation growth (R2 0.9, P < 0.01), and other features presented weaker correlations. Overall, this study determined the remote sensing phenology and climate drivers in two Chinese bogs, we suggested that vegetation phenology alternation should be concerned when carry on ecological processes and carbon dynamics researches in peatlands.
  • Gaudig, G.; Krebs, M.; Prager, A.; Wichmann, S.; Barney, M.; Caporn, S. J. M.; Emmel, M.; Fritz, C.; Graf, M.; Grobe, A.; Pacheco, S. Gutierrez; Hogue-Hugron, S.; Holztraeger, S.; Irrgang, S.; Kämäräinen, A.; Karofeld, E.; Koch, G.; Koebbing, J. F.; Kumar, S.; Matchutadze, I.; Oberpaur, C.; Oestmann, J.; Raabe, P.; Rammes, D.; Rochefort, L.; Schmilewksi, G.; Sendzikaite, J.; Smolders, A.; St-Hilaire, B.; van de Riet, B.; Wright, B.; Wright, N.; Zoch, L.; Joosten, H. (2017)
    Sphagnum farming - the production of Sphagnum biomass on rewetted bogs - helps towards achieving global climate goals by halting greenhouse gas emissions from drained peat and by replacing peat with a renewable biomass alternative. Large-scale implementation of Sphagnum farming requires a wide range of know-how, from initial species selection up to the final production and use of Sphagnum biomass based growing media in horticulture. This article provides an overview of relevant knowledge accumulated over the last 15 years and identifies open questions.
  • Juutinen, Artti; Saarimaa, Miia; Ojanen, Paavo; Sarkkola, Sakari; Haara, Arto; Karhu, Jouni; Nieminen, Mika; Minkkinen, Kari; Penttila, Timo; Laatikainen, Matti; Tolvanen, Anne (2019)
    Economic development creates challenges for land-use planners in balancing between increasing the use of natural resources and safeguarding biodiversity and ecosystem services. We developed and utilized multi-objective numeric optimization models to analyze the trade-offs between biodiversity and ecosystem services (BES). The approach was used in the land-use planning process in northern Finland when selecting potential peat production sites as a part of the development of the regional master plan. We first quantified Net Present Value (NPV) of peat production, biodiversity, greenhouse gas (GHG) emissions, and water emissions of peatlands. Then we applied multi-objective optimization to examine the trade-offs between the variables as well as to determine a cost-efficient selection of potential peat production sites, that is, a selection which would simultaneously generate the greatest possible economic returns and environmental benefits. Our results showed that with a relatively small decrease in NPV, a substantial decrease in biodiversity loss and a reduction in water emissions compared to the benchmark level could be attained. However, a significant decrease in GHG emissions resulted in a substantial decrease in NPV. We conclude that it is possible to significantly improve land-use management by applying multi-objective optimization in land-use planning.
  • Smith, Stuart W.; Rahman, Nur Estya Binte; Harrison, Mark E.; Shiodera, Satomi; Giesen, Wim; Lampela, Maija; Wardle, David A.; Chong, Kwek Yan; Randi, Agusti; Wijedasa, Lahiru S.; Teo, Pei Yun; Fatimah, Yuti A.; Teng, Nam Thian; Yeo, Joanne K. Q.; Alam, Md Jahangir; Sintes, Pau Brugues; Darusman, Taryono; Graham, Laura L. B.; Katoppo, Daniel Refly; Kojima, Katsumi; Kusin, Kitso; Lestari, Dwi Puji; Metali, Faizah; Morrogh-Bernard, Helen C.; Nahor, Marlide B.; Napitupulu, Richard R. P.; Nasir, Darmae; Nath, Tapan Kumar; Nilus, Reuben; Norisada, Mariko; Rachmanadi, Dony; Rachmat, Henti H.; Capilla, Bernat Ripoll; Salahuddin, NAWAL; Santosa, Purwanto B.; Sukri, Rahayu S.; Tay, Benjamin; Tuah, Wardah; Wedeux, Beatrice M. M.; Yamanoshita, Takashi; Yokoyama, Elisa Yukie; Yuwati, Tri Wira; Lee, Janice S. H. (2022)
    Degraded tropical peatlands lack tree cover and are often subject to seasonal flooding and repeated burning. These harsh environments for tree seedlings to survive and grow are therefore challenging to revegetate. Knowledge on species performance from previous plantings represents an important evidence base to help guide future tropical peat swamp forest (TPSF) restoration efforts. We conducted a systematic review of the survival and growth of tree species planted in degraded peatlands across Southeast Asia to examine (1) species differences, (2) the impact of seedling and site treatments on survival and growth and (3) the potential use of plant functional traits to predict seedling survival and growth rates. Planted seedling monitoring data were compiled through a systematic review of journal articles, conference proceedings, reports, theses and unpublished datasets. In total, 94 study-sites were included, spanning three decades from 1988 to 2019, and including 141 indigenous peatland tree and palm species. Accounting for variable planting numbers and monitoring durations, we analysed three measures of survival and growth: (1) final survival weighted by the number of seedlings planted, (2) half-life, that is, duration until 50% mortality and (3) relative growth rates (RGR) corrected for initial planting height of seedlings. Average final survival was 62% and half-life was 33 months across all species, sites and treatments. Species differed significantly in survival and half-life. Seedling and site treatments had small effects with the strongest being higher survival of mycorrhizal fungi inoculated seedlings; lower survival, half-life and RGR when shading seedlings; and lower RGR and higher survival when fertilising seedlings. Leaf nutrient and wood density traits predicted TPSF species survival, but not half-life and RGR. RGR and half-life were negatively correlated, meaning that slower growing species survived for longer. Synthesis and applications. To advance tropical peat swamp reforestation requires expanding the number and replication of species planted and testing treatments by adopting control vs. treatment experimental designs. Species selection should involve slower growing species (e.g. Lophopetalum rigidum, Alstonia spatulata, Madhuca motleyana) that survive for longer and explore screening species based on functional traits associated with nutrient acquisition, flooding tolerance and recovery from fire.
  • Laine, A.M.; Mäkiranta, P.; Laiho, R.; Mehtätalo, L.; Penttilä, T.; Korrensalo, A.; Minkkinen, K.; Fritze, H.; Tuittila, E-S (2019)
    Abstract Northern peatlands form a major soil carbon (C) stock. With climate change, peatland C mineralization is expected to increase, which in turn would accelerate climate change. A particularity of peatlands is the importance of soil aeration, which regulates peatland functioning and likely modulates the responses to warming climate. Our aim is to assess the impacts of warming on a southern boreal and a sub-arctic sedge fen carbon dioxide (CO2) exchange under two plausible water table regimes: wet and moderately dry. We focused this study on minerotrophic treeless sedge fens, as they are common peatland types at boreal and (sub)arctic areas, which are expected to face the highest rates of climate warming. In addition, fens are expected to respond to environmental changes faster than the nutrient poor bogs. Our study confirmed that CO2 exchange is more strongly affected by drying than warming. Experimental water level draw-down (WLD) significantly increased gross photosynthesis and ecosystem respiration. Warming alone had insignificant impacts on the CO2 exchange components, but when combined with WLD it further increased ecosystem respiration. In the southern fen, CO2 uptake decreased due to WLD, which was amplified by warming, while at northern fen it remained stable. As a conclusion, our results suggest that a very small difference in the WLD may be decisive, whether the C sink of a fen decreases, or whether the system is able to adapt within its regime and maintain its functions. Moreover, the water table has a role in determining how much the increased temperature impacts the CO2 exchange. This article is protected by copyright. All rights reserved.
  • Zhang, Hui; Tuittila, Eeva-Stiina; Korrensalo, Aino; Rasänen, Aleksi; Virtanen, Tarmo; Aurela, Mika; Penttilä, Timo; Laurila, Tuomas; Gerin, Stephanie; Lindholm, Viivi; Lohila, Annalea (2020)
    Northern peatlands are projected to be crucial in future atmospheric methane (CH4) budgets and have a positive feedback on global warming. Fens receive nutrients from catchments via inflowing water and are more sensitive than bogs to variations in their ecohydrology. Yet, due to a lack of data detailing the impacts of moving water on microhabitats and CH4 fluxes in fens, large uncertainties remain with respect to predicting CH4 emissions from these sites under climate changes. We measured CH4 fluxes with manual chambers over three growing seasons (2017-2019) at a northern boreal fen. To address the spatial variation at the site where a stream flows through the long and narrow valley fen, we established sample plots at varying distances from the stream. To link the variations in CH4 emissions to environmental controls, we quantified water levels, peat temperature, dissolved oxygen concentration, vegetation composition, and leaf area index in combination with flux measurements during the growing season in 2019. We found that due to the flowing water, there was a higher water level, cooler peat temperatures, and more oxygen in the peat close to the stream, which also had the highest total leaf area and gross primary production (GPP) values but the lowest CH4 emissions. CH4 emissions were highest at an intermediate distance from the stream where the oxygen concentration in the surface peat was low but GPP was still high. Further from the stream, the conditions were drier and produced low CH4 emissions. Our results emphasize the key role of ecohydrology in CH4 dynamics in fens and, for the first time, show how a stream controls CH4 emissions in a flow-through fen. As valley fens are common peatland ecosystems from the Arctic to the temperate zones, future projections of global CH4 budgets need to take flowing water features into account.