Editorial: Sustainable and Climate-Smart Agriculture in the Boreal and Arctic Regions

Peer Reviewe

Key factors determining biochar sorption capacity for metal contaminants: a literature synthesis

The sorption capacity and affinity of biochar for metals are both important attributes that determine biochar’s suitability as a soil amendment for contaminant mitigation, yet few analyses have considered both characteristics simultaneously. We present a systematic review of literature published between 2010 and 2018 to test the hypothesis that sorption capacity and affinity are affected by biochar properties, attributes of the metal contaminant, and experimental conditions, in that order. We used random forest (RF) and multi-objective optimization to analyze data of 559 individual Langmuir adsorption isotherms extracted from 133 studies covering the sorption capacity (Cmax) and affinity (KL) of biochar for 17 different metals, elaborated from six different feedstock classes, three different types of feedstock pretreatment, and five types of post-pyrolysis treatment. Highest sorption values were obtained for Pb(II), Cr(IV), and Cd(II). The feedstock used was the key determinant influencing biochar’s capacity and affinity to sorb metal contaminants (first and fourth most important variable in RF models for Cmax and KL, respectively) with best results obtained for biochar elaborated from nutrient-dense feedstocks (animal biowaste, sludge, and manure). Biochars that had both high sorption capacity and affinity were the result of a longer duration of pyrolysis; they had lower C and higher N and O content, as well as lower C/N and higher O/C and H/C ratios, higher pore volumes and higher pH. Applying some form of pretreatment was better than none, whereas chemical modification was the best of the post-treatment methods analyzed. This review demonstrates clearly that multiple parameters during the preparation process influence the effectiveness of biochar to immobilize metal contaminants. Future research that focuses on mechanisms and the underlying factors for the correlations observed should allow the development of biochar formulations that are even more effective at immobilizing metal contaminants in soils and sediments

Will CO2 Emissions from Drained Tropical Peatlands Decline Over Time? Links Between Soil Organic Matter Quality, Nutrients, and C Mineralization Rates

Peer Revie

New Tropical Peatland Gas and Particulate Emissions Factors Indicate 2015 Indonesian Fires Released Far More Particulate Matter (but Less Methane) than Current Inventories Imply

Deforestation and draining of the peatlands in equatorial SE Asia has greatly increased their flammability, and in September-October 2015 a strong El Niño-related drought led to further drying and to widespread burning across parts of Indonesia, primarily on Kalimantan and Sumatra. These fires resulted in some of the worst sustained outdoor air pollution ever recorded, with atmospheric particulate matter (PM) concentrations exceeding those considered "extremely hazardous to health" by up to an order of magnitude. Here we report unique in situ air quality data and tropical peatland fire emissions factors (EFs) for key carbonaceous trace gases (CO2, CH4 and CO) and PM2.5 and black carbon (BC) particulates, based on measurements conducted on Kalimantan at the height of the 2015 fires, both at locations of "pure" sub-surface peat burning and spreading vegetation fires atop burning peat. PM2.5 are the most significant smoke constituent in terms of human health impacts, and we find in situ PM2.5 emissions factors for pure peat burning to be 17.8 to 22.3 g·kg-1, and for spreading vegetation fires atop burning peat 44 to 61 g·kg-1, both far higher than past laboratory burning of tropical peat has suggested. The latter are some of the highest PM2.5 emissions factors measured worldwide. Using our peatland CO2, CH4 and CO emissions factors (1779 ± 55 g·kg-1, 238 ± 36 g·kg-1, and 7.8 ± 2.3 g·kg-1 respectively) alongside in situ measured peat carbon content (610 ± 47 g-C·kg-1) we provide a new 358 Tg (± 30%) fuel consumption estimate for the 2015 Indonesian fires, which is less than that provided by the GFEDv4.1s and GFASv1.2 global fire emissions inventories by 23% and 34% respectively, and which due to our lower EFCH4 produces far less (~3×) methane. However, our mean in situ derived EFPM2.5 for these extreme tropical peatland fires (28 ± 6 g·kg-1) is far higher than current emissions inventories assume, resulting in our total PM2.5 emissions estimate (9.1 ± 3.5 Tg) being many times higher than GFEDv4.1s, GFASv1.2 and FINNv2, despite our lower fuel consumption. We find that two thirds of the emitted PM2.5 come from Kalimantan, one third from Sumatra, and 95% from burning peatlands. Using new geostationary fire radiative power (FRP) data we map the fire emissions' spatio-temporal variations in far greater detail than ever before (hourly, 0.05°), identifying a tropical peatland fire diurnal cycle twice as wide as in neighboring non-peat areas and peaking much later in the day. Our data show that a combination of greatly elevated PM2.5 emissions factors, large areas of simultaneous, long-duration burning, and very high peat fuel consumption per unit area made these Sept to Oct tropical peatland fires the greatest wildfire source of particulate matter globally in 2015, furthering evidence for a regional atmospheric pollution impact whose particulate matter component in particular led to millions of citizens being exposed to extremely poor levels of air quality for substantial periods. © 2018 by the authors

Biochar as a tool to reduce the agricultural greenhouse-gas burden–knowns, unknowns and future research needs

Agriculture and land use change has significantly increased atmospheric emissions of the non-CO2 green-house gases (GHG) nitrous oxide (N2O) and methane (CH4). Since human nutritional and bioenergy needs continue to increase, at a shrinking global land area for production, novel land management strategies are required that reduce the GHG footprint per unit of yield. Here we review the potential of biochar to reduce N2O and CH4 emissions from agricultural practices including potential mechanisms behind observed effects. Furthermore, we investigate alternative uses of biochar in agricultural land management that may significantly reduce the GHG-emissions-per-unit-of-product footprint, such as (i) pyrolysis of manures as hygienic alternative to direct soil application, (ii) using biochar as fertilizer carrier matrix for underfoot fertilization, biochar use (iii) as composting additive or (iv) as feed additive in animal husbandry or for manure treatment. We conclude that the largest future research needs lay in conducting life-cycle GHG assessments when using biochar as an on-farm management tool for nutrient-rich biomass waste streams. © 2017 The Author(s) Published by VGTU Press and Informa UK Limited, [trading as Taylor & Francis Group]

Biochar research activities and their relation to development and environmental quality. A meta-analysis

Biochar is the solid product that results from pyrolysis of organic materials. Its addition to highly weathered soils changes physico-chemical soil properties, improves soil functions and enhances crop yields. Highly weathered soils are typical of humid tropics where agricultural productivity is low and needs to be raised to reduce human hunger and poverty. However, impact of biochar research on scientists, politicians and end-users in poor tropical countries remains unknown; assessing needs and interests on biochar is essential to develop reliable knowledge transfer/translation mechanisms. The aim of this publication is to present results of a meta-analysis conducted to (1) survey global biochar research published between 2010 and 2014 to assess its relation to human development and environmental quality, and (2) deduce, based on the results of this analysis, priorities required to assess and promote the role of biochar in the development of adapted and sustainable agronomic methods. Our main findings reveal for the very first time that: (1) biochar research associated with less developed countries focused on biochar production technologies (26.5 ± 0.7%), then on biochars’ impact on chemical soil properties (18.7 ± 1.2%), and on plant productivity (17.1 ± 2.6%); (2) China dominated biochar research activities among the medium developed countries focusing on biochar production technologies (26.8 ± 0.5%) and on use of biochar as sorbent for organic and inorganic compounds (29.1 ± 0.4%); and (3) the majority of biochar research (69.0±2.9%) was associated with highly developed countries that are able to address a higher diversity of questions. Evidently, less developed countries are eager to improve soil fertility and agricultural productivity, which requires transfer and/or translation of biochar knowledge acquired in highly developed countries. Yet, improving local research capacities and encouraging synergies across scientific disciplines and countries are crucial to foster development of sustainable agronomy in less developed countries. © 2017, The Author(s)

Roadmap for the European Joint Program SOIL: Towards Climate-Smart Sustainable Management of Agricultural Soils

peer-reviewedhis article belongs to the Proceedings of TERRAenVISION 2019Our planet suffers from humankind’s impact on natural resources, biogeochemical cycles and ecosystems. Intensive modern agriculture with inappropriate inputs of fertilisers, pesticides and fossil fuel –based energy has increasingly added to human pressure on the environment. As a key element of our natural capital, soils are also under threat, despite being essential to provide food, feed, fibre and fuel for an increasing global population. Moreover, soils play a key role in carbon, water and energy cycles, highlighting their importance for biomass provision and the circular bioeconomy. Evidently, these new and complex challenges cannot be resolved effectively with existing knowledge and experience alone. These challenges require scientific research, interdisciplinary collaboration and networking to find context-specific and tailored solutions addressing societal issues of our time and facilitating the adoption of these solutions. The most effective approaches are based on the involvement of multiple actors from science, policy, economy, civil society and farming that have the same goal, work on the same societal issue, but have complementing backgrounds, expertise and perceptions. The European Joint Programme (EJP) SOIL is a European network of research institutes in the field of soil science and agricultural soil management that will provide science-based advice to practitioners and policymakers, at local, national and European level. The EJP SOIL aims to align and boost research, training and capacity building through joint programming activities co-funded by the European Commission and national research programs. This will reduce current fragmentation and help to find synergies in order to make a leapfrog in research on good agricultural soil management in three main areas: climate change mitigation and adaptation, production capacity in healthy food systems, and environmental sustainability. By joint programming, training and capacity building, EJP SOIL will also take into account the need for effective policy solutions, as well as the socio-economic conditions of all stakeholders in the agricultural value chain. Thus, a key focus of the EJP SOIL is to build and strengthen a framework for an integrated community of research groups working on related aspects of agricultural soil management. As part of this effort, EJP SOIL will co-construct with stakeholders a roadmap for agricultural soil research. To develop a structured roadmap, EJP SOIL works with a version of the knowledge management framework of Dalkir (2005). The EJP version uses four compartments: (i) Knowledge development, (ii) knowledge harmonisation, organisation and storage (iii) knowledge sharing and transfer, and (iv) knowledge application. The four segments are part of a cyclic process to enhance the development and use of knowledge on agricultural soils. Knowledge development comprises assessing new knowledge needs to achieve the expected impacts of EJP SOIL. Therefore, by involving multiple stakeholders, knowledge gaps across Europe will be identified to work towards the adoption of Climate-Smart Sustainable Agricultural Soil Management (CSSASM). Within the knowledge sharing and transfer compartment, the capacity of scientists, advisors, policy makers, farmers and other stakeholders will be strengthened. EJP SOIL will work to support networks and co-creation of new knowledge with stakeholder groups, stimulating innovation in CSSASM. The knowledge harmonization, organization and storage compartment of the knowledge framework ensures linkages with all stakeholders to guarantee data harmonization and standardization. The last compartment, application of knowledge, will be facilitated by creating better guidelines, awareness and capacity for Climate-Smart Sustainable Agricultural Soil Management adoption and by strengthening science-to-policy processes at EU and Member State level

Roadmap for the European Joint Program SOIL: Towards Climate-Smart Sustainable Management of Agricultural Soils

Our planet suffers from humankind’s impact on natural resources, biogeochemical cycles and ecosystems. Intensive modern agriculture with inappropriate inputs of fertilisers, pesticides and fossil fuel –based energy has increasingly added to human pressure on the environment. As a key element of our natural capital, soils are also under threat, despite being essential to provide food, feed, fibre and fuel for an increasing global population. Moreover, soils play a key role in carbon, water and energy cycles, highlighting their importance for biomass provision and the circular bioeconomy. Evidently, these new and complex challenges cannot be resolved effectively with existing knowledge and experience alone. These challenges require scientific research, interdisciplinary collaboration and networking to find context-specific and tailored solutions addressing societal issues of our time and facilitating the adoption of these solutions. The most effective approaches are based on the involvement of multiple actors from science, policy, economy, civil society and farming that have the same goal, work on the same societal issue, but have complementing backgrounds, expertise and perceptions. The European Joint Programme (EJP) SOIL is a European network of research institutes in the field of soil science and agricultural soil management that will provide science-based advice to practitioners and policymakers, at local, national and European level. The EJP SOIL aims to align and boost research, training and capacity building through joint programming activities co-funded by the European Commission and national research programs. This will reduce current fragmentation and help to find synergies in order to make a leapfrog in research on good agricultural soil management in three main areas: climate change mitigation and adaptation, production capacity in healthy food systems, and environmental sustainability. By joint programming, training and capacity building, EJP SOIL will also take into account the need for effective policy solutions, as well as the socio-economic conditions of all stakeholders in the agricultural value chain. Thus, a key focus of the EJP SOIL is to build and strengthen a framework for an integrated community of research groups working on related aspects of agricultural soil management. As part of this effort, EJP SOIL will co-construct with stakeholders a roadmap for agricultural soil research. To develop a structured roadmap, EJP SOIL works with a version of the knowledge management framework of Dalkir (2005). The EJP version uses four compartments: (i) Knowledge development, (ii) knowledge harmonisation, organisation and storage (iii) knowledge sharing and transfer, and (iv) knowledge application. The four segments are part of a cyclic process to enhance the development and use of knowledge on agricultural soils. Knowledge development comprises assessing new knowledge needs to achieve the expected impacts of EJP SOIL. Therefore, by involving multiple stakeholders, knowledge gaps across Europe will be identified to work towards the adoption of Climate-Smart Sustainable Agricultural Soil Management (CSSASM). Within the knowledge sharing and transfer compartment, the capacity of scientists, advisors, policy makers, farmers and other stakeholders will be strengthened. EJP SOIL will work to support networks and co-creation of new knowledge with stakeholder groups, stimulating innovation in CSSASM. The knowledge harmonization, organization and storage compartment of the knowledge framework ensures linkages with all stakeholders to guarantee data harmonization and standardization. The last compartment, application of knowledge, will be facilitated by creating better guidelines, awareness and capacity for Climate-Smart Sustainable Agricultural Soil Management adoption and by strengthening science-to-policy processes at EU and Member State level202

The Permafrost-Agroecosystem Action Group: first results and future goals

Permafrost-agroecosystems encompass northern social-ecological systems which include both cultivation of arable permafrost-affected soils, and animal husbandry practices. These heterogeneous food and cultural systems are being affected by a warming climate. Examples include increasing opportunities for growing crops through longer growing seasons, as well as impacts on animals’ local and long-distance migratory movements and their food sources. Furthermore, climate change driven permafrost thaw and thaw accelerated by land clearance is rapidly changing the biophysical and socioeconomic aspects of these systems. Therefore, an international collaboration encompassing experts from North America, Europe and Asia is working on increasing our understanding of permafrost-agroecosystems and contributing to the adaptation, resilience, and sustainability strategy of these rapidly evolving systems. The International Permafrost Association Permafrost-Agroecosystem Action Group is composed of ~30 members from 7 countries. The objectives of our action group are to share knowledge and build networking capacities through meetings and webinar presentation as well as to collaborate on publications and produce the first geospatial dataset of permafrost-agroecosystems. Our poster presentation provides an overview of the group’s activities including providing case studies from a range of high-latitude and high-altitude areas as part of a group manuscript in preparation and an update on our mapping activities

Socioecological dynamics of diverse global permafrost-agroecosystems under environmental change

Permafrost-agroecosystems include all cultivation and pastoral activities in areas underlain by permafrost. These systems support local livelihoods and food production and are rarely considered in global agricultural studies but may become more relevant as climate change is increasing opportunities for food production in high latitude and mountainous areas. The exact locations and amount of agricultural production in areas containing permafrost are currently unknown, therefore we provide an overview of countries where both permafrost and agricultural activities are present. We highlight the socioecological diversity and complexities of permafrostagroecosystems through seven case studies: (1) crop cultivation in Alaska, USA; (2) Indigenous food systems and crop cultivation in the Northwest Territories, Canada; (3) horse and cattle husbandry and Indigenous hay production in the Sakha Republic, Russia; (4) mobile pastoralism and husbandry in Mongolia; (5) yak pastoralism in the Central Himalaya, Nepal; (6) berry picking and reindeer herding in northern Fennoscandia; and (7) reindeer herding in northwest Russia. We discuss regional knowledge gaps associated with permafrost and make recommendations to policy makers and land users for adapting to changing permafrost environments. A better understanding of permafrost-agroecosystems is needed to help sustainably manage and develop these systems considering rapidly changing climate, environments, economies, and industries