Publications
NIBIOs employees contribute to several hundred scientific articles and research reports every year. You can browse or search in our collection which contains references and links to these publications as well as other research and dissemination activities. The collection is continously updated with new and historical material.
2021
Abstract
Biochar-based fertilizer products (BCF) are receiving increasing attention as potential win-win solutions for mitigating climate change and improving agricultural production. BCFs are reported to increase yields through increased N use efficiency, an effect which is often assumed to result from the slow-release of adsorbed N forms into the soil. Here, we review the magnitude of this effect, the potential for further improvement and the need to consider other mechanisms in product development. Current high-N commercial BCFs are mostly physical blends of biochar and mineral fertilizer, with little evidence of slow-release effects supported by sorption mechanisms. For such products, the main effect potentially results from root-growth promoting factors and from increases in soil pH and Eh and stimulation of beneficial micro-organisms in the rhizosphere, which all result in an increase in uptake of specific nutrients. Our reanalysis of literature data indicates that the median sorption capacity of untreated biochar for mineral N forms requires applying 200 times more biochar than N fertilizer. This ratio needs reducing by at least an order of magnitude for producing efficient sorption-based BCFs. Activation of biochar with acids and oxidizing agents, as reported in many studies, appears to only marginally increase sorption capacity in absolute values. Fixation of clay and organics within the porous structure of biochar appears a more promising technology, suggesting that macro- and mesoporosity is a key biochar property that deserves greater scrutiny and research towards making efficient sorption-based BCFs. Mechanisms of action and dose responses need to be more systematically studied in order to devise products that combine positive effects and can be used within realistic agronomic management practices. Long-term effects resulting from accumulated annual inputs of BCF also need to be better evaluated in terms of nutrient cycling and the progressive improvement of soil health.
Authors
Alexandre Tisserant Marjorie Morales Otávio Cavalett Adam O'Toole Simon Weldon Daniel Rasse Francesco CherubiniAbstract
Limiting temperature rise below 2 °C requires large deployment of Negative Emission Technologies (NET) to capture and store atmospheric CO2. Compared to other types of NETs, biochar has emerged as a mature option to store carbon in soils while providing several co-benefits and limited trade-offs. Existing life-cycle assessment studies of biochar systems mostly focus on climate impacts from greenhouse gasses (GHGs), while other forcing agents, effects on soil emissions, other impact categories, and the implications of a large-scale national deployment are rarely jointly considered. Here, we consider all these aspects and quantify the environmental impacts of application to agricultural soils of biochar from forest residues available in Norway considering different scenarios (including mixing of biochar with synthetic fertilizers and bio-oil sequestration for long-term storage). All the biochar scenarios deliver negative emissions under a life-cycle perspective, ranging from -1.72 ± 0.45 tonnes CO2-eq. ha−1 yr−1 to -7.18 ± 0.67 tonnes CO2-eq. ha−1 yr−1 (when bio-oil is sequestered). Estimated negative emissions are robust to multiple climate metrics and a large range of uncertainties tested with a Monte-Carlo analysis. Co-benefits exist with crop yields, stratospheric ozone depletion and marine eutrophication, but potential trade-offs occur with tropospheric ozone formation, fine particulate formation, terrestrial acidification and ecotoxicity. At a national level, biochar has the potential to offset between 13% and 40% of the GHG emissions from the Norwegian agricultural sector. Overall, our study shows the importance of integrating emissions from the supply chain with those from agricultural soils to estimate mitigation potentials of biochar in specific regional contexts.
Authors
Liang Wang Alba Dieguez-Alonso Maria Nicte Polanco Olsen Alice Budai Daniel Rasse Øyvind SkreibergAbstract
No abstract has been registered
Authors
Liang Wang Alba Dieguez-Alonso Maria Nicte Polanco Olsen Alice Budai Daniel Rasse Ondřej Mašek Øyvind SkreibergAbstract
No abstract has been registered
Authors
Leonor Rodrigues Julia Fohrafellner Brieuc Hardy Bruno Huyghebaert Jens Leifeld Alberto Sanz Cobeña Alice Budai Andis Lazdiņš Arezoo Taghizadeh Axel Don Bartosz Adamczyk Benjamin Gimeno Benjamin Sanchez Bo Stenberg Claudia Di Bene Corina Carranca Dalia Feiziene Daniel Rasse Daria Seitz Dario Fornara Eduardo Aguilera Elena Rodriguez Eloïse Mason Erich Inselsbacher Gabriela Barančíková Grzegorz Siebielec Heide Spiegel Imants Kukuļs Jacek Niedźwiecki Jan P. Lesschen Karin Kauer Kestutis Armolaitis Lilian OSullivan Lenka Pavlu Maarten De Boever Nils Kauer Peter Kuikman Peter Laszlo Raquel Mano Raimonds Kasparinskis Rok Mihelič Sevinc Madenoglu Sophie Cornu Sophie Zechmeister-Boltenstern Stephan Glatzel Sylvain Pellerin Teresa Gómez de la Bárcena Thalisa Slier Thomas Kätterer Martin A. Bolinder Kerstin Berglund Toth Toth GergelyAbstract
Deliverable 2.3. This synthesis identifies the available knowledge of achievable carbon sequestration in mineral soils and GHGs mitigation in organic soils in agricultural land, including pasture/grassland across Europe. The inventory of past and current studies on carbon sequestration and GHGs mitigation measures in agricultural soils and the methodology used for the assessment were considered from 25 Member states (MS) across Europe. The stocktake shows that availability of datasets concerning soil carbon sequestration (SCS) is variable among Europe. While northern Europe and central Europe is relatively well studied, there is a lack of studies comprising parts of Southern, Southeaster and Western Europe. Further, it can be concluded that at present country based knowledge and engagement is still poor; very few countries have an idea on their national-wide achievable carbon sequestration potential. The presented national SCS potentials (MS n=13) do however point towards important contributions to mitigate climate change by covering considerable shares of national greenhouse gas emissions from the agricultural sector in the range of 0.1-27 %, underpinning the importance of further investigations. In contrast to mineral soils, effective mitigation measures for organic soils while maintaining industrial agricultural production are still in its infancy. Very few mitigation options exist to mitigate GHG emissions without compromising agricultural production. Most GHG mitigation practices reported by the MS involve the restoration of organic soils, which means a complete abandonment of land from any agricultural use. Only one contribution (NL) reports possible mitigation potentials, which are based on specific water management measures (water level fixation). Nevertheless, there is an increasing awareness of the need of mitigation measures reflected by the several ongoing research projects on peatland management.
Authors
A. Astover J. Escuer-Gatius A. Don K. Armolaitis G. Barančíková M. Bolinder S. Cornu M. De Boever R. Farina C. Foldal R. Jandl M. Kasper D. Fornara A. Govednik R. Mihelič Vrščaj B. B. Huyghebaert R. Kasparinskis S.G. Keel P. Laszlo A. Lehtonen S. Madenoğlu G. Maria da Conceição Christophe Moni L. O'Sullivan D. Wall G. Lanigan B. Sánchez Gimeno A. Taghizadeh-ToosiAbstract
Deliverable 2.12. This report presents a picture of the inventory of the different models accounting and monitoring soil quality and soil carbon stocks used in 21 different countries in Europe, and especially for the reporting of greenhouse gas (GHG) emissions to the UNFCCC (UNFCCC, 2020). The report synthesizes the information collected regarding the use of these models both at national and farm scale, as well as information of other models for soil quality monitoring, by different actors (policy making, farmers, and extension services). The study identified a big variability in the models used at national level and GHG reporting, where the Yasso07 model is currently the most widely used, and with several countries planning its implementation in the future. The number of models used at the farm scale to estimate SOC change presented an even bigger variability than those reported at the national scale, including some of the models included in the national scale, but also incorporating smaller spatial models intended for use at the farm scale, at the field scale or even at smaller scales. Most of the models are intended for mineral soils, both arable or grasslands, and only a few are reported for organic soils and/or other land use. A big heterogeneity was also present in the reported soil quality models (besides those used for accounting for SOC change). Two models included in the national and farm scale are also included here (RothC and Yasso07). The most reported soil quality models focus on greenhouse gas (GHG) emissions estimation and leaching, and are mainly related to the nitrogen cycle, but also to other nutrients, and soil physical properties. Our results show that synergies derived from European collaborations are not fully used but offer the possibility to enhance the quality of model applications for national GHG reporting and at smaller scales for the support of farm management.
Authors
Palingamoorthy Gnanamoorthy Qinghai Song Junbin Zhao Yiping Zhang Yuntong Liu Wenjun Zhou Liqing Sha Zexin Fan Pramit Kumar Deb BurmanAbstract
Subtropical forests are important ecosystems globally due to their extensive role in carbon sequestration. Extreme climate events are known to introduce disturbances in the ecosystem that cause long-term changes in carbon balance and radiation reflectance. However, how these ecosystem function changes contribute to global warming in terms of radiative forcing (RF), especially in the years following a disturbance, still needs to be investigated. We studied an extreme snow event that occurred in a subtropical evergreen broadleaved forest in south-western China in 2015 and used 9 years (2011–2019) of net ecosystem CO2 exchange (NEE) and surface albedo (α) data to investigate the effect of the event on the ecosystem RF changes. In the year of the disturbance, leaf area index (LAI) declined by 40% and α by 32%. The annual NEE was −718 ± 128 g C m−2 as a sink in the pre-disturbance years (2011–2014), but after the event, the sink strength dropped significantly by 76% (2015). Both the vegetation, indicated by LAI, and α recovered to pre-disturbance levels in the fourth post-disturbance year (2018). However, the NEE recovery lagged and occurred a year later in 2019, suggesting a more severe and lasting impact on the ecosystem carbon balance. Overall, the extreme event caused a positive (warming effect) net RF which was predominantly caused by changes in α (90%–93%) rather than those in NEE. This result suggests that, compared to the climate effect caused by forest carbon sequestration changes, the climate effect of α alterations can be more sensitive to vegetation damage induced by natural disturbances. Moreover, this study demonstrates the important role of vegetation recovery in driving canopy reflectance and ecosystem carbon balance during the post-disturbance period, which determines the ecosystem feedbacks to the climate change.
Authors
Wenjun Zhou Jing Zhu Hongli Ji John Grace Liqing Sha Qinghai Song Yuntong Liu Xiaolong Bai Youxing Lin Jinbo Gao Xuehai Fei Ruiwu Zhou Jianwei Tang Xiaobao Deng Guirui Yu Junhui Zhang Xunhua Zheng Junbin Zhao Yiping ZhangAbstract
With large area of primary tropical rainforest converted into rubber (Hevea brasiliensis) plantation in Southeast Asia, it is necessary to examine the change in soil CO2 and CH4 emissions, and their underlying drivers in tropical rainforest (TRF) and rubber plantation. In TRF and RP in Xishuangbanna Southwest China, we measured the soil CO2 , CH4 , temperature, and water content once each week from 2003 to 2008, and twice weeks in 2013 and 2014. Additionally, the concentrations of soil carbon (C) and nitrogen (N) fractions from 2013 to 2014 were observed. Inputs of litter and live, dead, decomposed fine roots dynamics were also included. TRF transplanted to RP did not change significantly the annual soil CO2 emissions (TRF, 359 ± 91 and RP 352 ± 41 mg CO2 m−2 h−1) but decreased soil CH4 uptake significantly (TRF, −0.11 ± 0.18 mg CH4 m−2 h−1) RP, −0.020 ± 0.087 mg CH4 m−2 h−1). The most important influence on soil CO2 and CH4 emissions in the RP was the leaf area index and soil water content, respectively, whereas the soil water content, soil temperature, and dead fine roots were the most important factors in the TRF. Variations in the soil CO2 and CH4 caused by land-use transition were individually explained by soil temperature and fine root growth and decomposition, respectively. The results show that land-use change varied the soil CH4 and CO2 emission dynamics and drivers by the variation of soil environmental and plant's factors.
Authors
Junbin Zhao Sparkle L. Malone Christina L. Staudhammer Gregory Starr Henrik Hartmann Steven. F. OberbauerAbstract
Premise Wetland plants regularly experience physiological stresses resulting from inundation; however, plant responses to the interacting effects of water level and inundation duration are not fully understood. Methods We conducted a mesocosm experiment on two wetland species, sawgrass (Cladium jamaicense) and muhly grass (Muhlenbergia filipes), that co-dominate many freshwater wetlands in the Florida Everglades. We tracked photosynthesis, respiration, and growth at water levels of −10 (control), 10 (shallow), and 35 cm (deep) with reference to soil surface over 6 months. Results The response of photosynthesis to inundation was nonlinear. Specifically, photosynthetic capacity (Amax) declined by 25% in sawgrass and by 70% in muhly grass after 1–2 months of inundation. After 4 months, Amax of muhly grass in the deep-water treatment declined to near zero. Inundated sawgrass maintained similar leaf respiration and growth rates as the control, whereas inundated muhly grass suppressed both respiration and growth. At the end of the experiment, sawgrass had similar nonstructural carbohydrate pools in all treatments. By contrast, muhly grass in the deep-water treatment had largely depleted sugar reserves but maintained a similar starch pool as the control, which is critical for post-stress recovery. Conclusions Overall, the two species exhibited nonlinear and contrasting patterns of carbon uptake and use under inundation stress, which ultimately defines their strategies of surviving regularly flooded habitats. The results suggest that a future scenario with more intensive inundation, due to the water management and climate change, may weaken the dominance of muhly grass in many freshwater wetlands of the Everglades.
Authors
Sparkle L. Malone Junbin Zhao John S. Kominoski Gregory Starr Christina L. Staudhammer Paulo C. Olivas Justin C. Cummings Steven F. OberbauerAbstract
How aquatic primary productivity influences the carbon (C) sequestering capacity of wetlands is uncertain. We evaluated the magnitude and variability in aquatic C dynamics and compared them to net ecosystem CO2 exchange (NEE) and ecosystem respiration (Reco) rates within calcareous freshwater wetlands in Everglades National Park. We continuously recorded 30-min measurements of dissolved oxygen (DO), water level, water temperature (Twater), and photosynthetically active radiation (PAR). These measurements were coupled with ecosystem CO2 fluxes over 5 years (2012–2016) in a long-hydroperiod peat-rich, freshwater marsh and a short-hydroperiod, freshwater marl prairie. Daily net aquatic primary productivity (NAPP) rates indicated both wetlands were generally net heterotrophic. Gross aquatic primary productivity (GAPP) ranged from 0 to − 6.3 g C m−2 day−1 and aquatic respiration (RAq) from 0 to 6.13 g C m−2 day−1. Nonlinear interactions between water level, Twater, and GAPP and RAq resulted in high variability in NAPP that contributed to NEE. Net aquatic primary productivity accounted for 4–5% of the deviance explained in NEE rates. With respect to the flux magnitude, daily NAPP was a greater proportion of daily NEE at the long-hydroperiod site (mean = 95%) compared to the short-hydroperiod site (mean = 64%). Although we have confirmed the significant contribution of NAPP to NEE in both long- and short-hydroperiod freshwater wetlands, the decoupling of the aquatic and ecosystem fluxes could largely depend on emergent vegetation, the carbonate cycle, and the lateral C flux.