Rapporten innehåller en analys av utsläppen av de sex klimatgaserna i Halland mellan 1990 och 2011, en skattning vad som kommer att genomföras till 2020 och förslag till åtgärder för att kunna leverera utsläppsreduktioner efter 2020. Resultaten visar att de halländska utsläppen har minskat med 20 procent sedan 1990, målet om 27 procent lägre utsläpp till 2020 kommer troligen att uppnås, transporter och jordbruk måste kunna leverera utsläppsreduktioner efter 2020, regionala plan- och styrdokument måste i större utsträckning kunna kvantifiera framtida utsläppsreduktioner samt att det behövs ett regionalt kompetenscenter i Halland för att länet ska kunna leverera utsläppsreduktioner i framtiden.

An increasing amount of CO2 emitted from human activities globally does not add to the increase in the atmosphere. Taking the ocean sink into acount, the fate of about 3 Gt C annually remains to be explained. This huge amount is calculated as the residual from known fluxes1 We present an `on the spot´ study that is based on systematic soil sampling in different regions and over the years since 2004. The difference between gross heterotrophic respiration (GHR) in the soil, and net heterotrophic respiration (NHR) that is the part of the carbon dioxide leaving the ground surface, was analyzed. The accumulated data indicate a within-soil CO2 sink of the same magnitude as the sink derived from different fluxes1 . Both approaches describe the same sink but our results show that the sink is CO2 uptake from the soil atmosphere, not emitted CO2 that is returned to some unknown area on land. The energy yield needed from nitrification to explain the observed reduction of CO2 to organic material is large, and NH4 + is recycled several times. It was unexpectedly observed that O2 was released in this gross nitrification cycle and this was confirmed with H2 18O incubations in soils2 . The large CO2 sink changes between seasons, between sites and even from a sink to an additional source, which may explain why it has so long been ”missing”.

1 Le Quéré et al. 2015. Global Carbon Budgets 2015. Earth Syst. Sci. Data 7, 349–396

2 Fleischer S. et al. 2013. Dark oxidation of water in soils. Tellus B 65, 20490

Bioenergicentrum i Halland (BEH) är ett projekt som ligger inom ramen för EU:s strukturfondsprogram. Projektet genomförs i Region Hallands regi som är regionens välfärds- och utvecklingsorganisation. Arbetet som bedrivs inom BEH syftar speciellt till att driva utvecklingen mot en ökad produktion och användning av bioenergi till biogas och i förlängningen fordonsgas. Genom att satsa på att skapa förutsättningar för innovation, kunskapsutveckling och samverkan främjas tillväxt och hållbar utveckling.

Vid naturbruksgymnasiet i Plönninge utanför Halmstad finns idag en biogasanläggning som beskickas med bl.a. nötgödsel och matavfall. Dessutom finns en mindre pilotanläggning som är tänkt att fungera som en del av test- och verifieringsanläggning som BEH vill bygga upp i Plönninge. Som ett led i att utveckla dessa anläggningar och kunna erbjuda möjligheten till kunskapsinsamling genomfördes projektet som beskrivs i denna rapport. Uppdraget var att genomföra försöksrötningar på labb, använda resultaten för att skapa en modell som sedan kan nyttjas som ett verktyg i det inledande arbetet med att investera i en biogasanläggning som beskickas med lantbruksbaserade substrat. Högskolan i Halmstad (HH) genomförde försöksrötningarna och Grontmij (GM) använde sedan resultaten för att skapa en modell där bl.a. substrat, förbehandlingsteknik och driftkostnader finns med.

Sammanfattningsvis kan sägas att majs som substrat fungerar bäst med de valda förbehandlingsmetoderna; kemisk behandling, termisk behandling och ultraljudsbehandling. Alla förbehandlingsmetoder med majs som substrat visade på ett positivt resultat, d.v.s. det ökade gasutbytet och dess värde (kr/kWh) översteg kostnaderna för de olika förbehandlingarna. Vad som måste beaktas är att produktionskostnaderna överlag är höga, med och utan förbehandling.

Modellen har konstruerats på ett sådant sätt att den ska vara användarvänlig och med möjlighet att enkelt lägga till ytterligare substrat och förbehandlingsmetoder. Upprepningar av de försöksrötningar som genomförts kommer att öka tillförlitligheten hos modellen. Den fungerar som ett verktyg i att beräkna investeringsmarginalen för förbehandlingsutrustningen baserat på det valda substratet. På detta vis kan intressenter få en första indikation på om det är ekonomiskt rimligt att gå vidare med det tänkta substratet, den valda förbehandlingsmetoden, de planerade mängderna substrat etc.

En investeringskalkyl har tagits fram för en gårdsanläggning som hanterar 5 000 ton substrat eller gödsel årligen. Det motsvarar 2-3 stycken medelstora mjölkgårdar. Kalkylen är översiktlig och syftar till att ge en första indikation på kostnader för de stora komponenterna såsom substratlager, rötkammare och rötrestlager. Kringarbeten såsom utredningar, markarbeten och geoundersökningar är inte med i kalkylen då dessa omkostnader till stor del avgörs av lokalisering och de förutsättningar som finns på platsen redan från start. Generellt kan dock sägas att den absolut billigaste och enklaste gårdsbaserade biogasanläggningen innebär en investering på 2,7-4 MSEK för flytgödsel från 100-300 mjölkkor.

För BEH är det viktigt att skapa en plattform där intressenter kan komma för att genomföra försöksrötningar, byta erfarenheter och samla kunskap. För att uppnå detta är det nödvändigt att kunna erbjuda kunden kompletta och kompetenta lösningar på en och samma plats. Detta innebär ett erbjudande som innefattar försöksrötningar på labb-, pilot och fullskala. Ett förslag på konstruktion av pilotanläggning med övergripande principskiss ingår i denna rapport och fungerar som ett inledande arbete i projekteringen av en större pilotanläggning. Nödvändiga driftanalyser av rötrest ska kunna göras på plats i Plönninge på laboratoriet; analyser såsom enskilda organiska syror ska kunna skickas till lämpligt laboratorium. Personal ska kunna tillhandahållas för att driva och optimera rötningen enligt kundens syften och önskemål. På detta vis fungerar Region Halland som en länk mellan teori ochpraktik, mellan liten och stor skala och mellan aktörer från olika discipliner och geografiska områden.

Ammonia exchange fluxes between grassland and the atmosphere were modelled on the basis of stomatal compensation points and leaf surface chemistry, and compared with measured fluxes during the GRAMINAE intensive measurement campaign in spring 2000 near Braunschweig, Germany. Leaf wetness and dew chemistry in grassland were measured together with ammonia fluxes and apoplastic NH4+ and H+ concentration, and the data were used to apply, validate and further develop an existing model of leaf surface chemistry and ammonia exchange. Foliar leaf wetness which is known to affect ammonia fluxes may be persistent after the end of rainfall, or sustained by recondensation of water vapour originating from the ground or leaf transpiration, so measured leaf wetness values were included in the model. pH and ammonium concentrations of dew samples collected from grass were compared to modelled values.

The measurement period was divided into three phases: a relatively wet phase followed by a dry phase in the first week before the grass was cut, and a second drier week after the cut. While the first two phases were mainly characterised by ammonia deposition and occasional short emission events, regular events of strong ammonia emissions were observed during the post-cut period. A single-layer resistance model including dynamic cuticular and stomatal exchange could describe the fluxes well before the cut, but after the cut the stomatal compensation points needed to numerically match measured fluxes were much higher than the ones measured by bioassays, suggesting another source of ammonia fluxes. Considerably better agreement both in the direction and the size range of fluxes were obtained when a second layer was introduced into the model, to account for the large additional ammonia source inherent in the leaf litter at the bottom of the grass canopy. Therefore, this was found to be a useful extension of the mechanistic dynamic chemistry model by keeping the advantage of requiring relatively little site-specific information.

This study evaluates the impacts of three different pretreatment methods on the biogas production from sugar beet, when it is anaerobically digested with a variety of inoculum mixing ratios. In this context, this research focuses on the influences of different pretreatment methods and inoculum on the digestibility on the digestibility. Sugar beet was anaerobically digested at 37°C. Actively digested cow manure slurry, vegetable and fruit residues mix was used as inoculum. The series of laboratory experiments using 32 digesters (each 1 L) were performed in batch operation mode. The results prove that inoculum and pretreatments could either enhance the biogas potential or totally inhibit the digestion. Key words: sugar beet, inoculum, pretreatment methods, biogas production.

Perception and awareness can affect behaviour and decision-making, for example, how companies implement Circular Economy (CE) practices. However, there is limited empirical research about this topic. Thus, we investigated the perception and awareness of representatives from water-intensive and bio-based sectors regarding the CE concept based on interviews and a survey with 10 companies in Sweden. Our results indicate that CE is understood mainly as zero waste and its key principles are resource efficiency and ecodesign. Missing (or partially addressed) important elements of CE are consumption, social aspects, regenerative role of CE, collaboration, and Industrial Symbiosis. The main benefit from implementing circular strategies is economic, and the main barrier is the lack of financial resources. The bio-based companies have a broader understanding of CE and its benefits than the water-intensive companies. Overall, more clarification and standardisation of the CE concept is necessary to avoid misunderstanding with other concepts such as sustainability. © 2024 The Authors

The measurement of progress towards Circular Economy (CE) within a company is crucial for identifying opportunities and designing circular practices. However, most of the existing tools do not consider the systemic view and principles of CE. The aim of this paper is to assess the contributions and limitations of CE assessment tools regarding the key elements: social dimension, stakeholder engagement, R-imperatives and industrial symbiosis. Also, the aim is to offer guidance for improvements towards a CE transition. The methodology was an integrative literature review; then based on the critical assessment of tools a guide was created. Thirty-eight tools were thoroughly analysed and our results show that there is a limited number of multidisciplinary tools (only 10), that is including all CE key elements, and in some cases partly. Social dimension is not fully explored; only 6 tools have indicators related to society, local community, customers, and workers. Recommendations for future tools development include to offer training for possible users of the tools and to develop tools for the service sector. Finally, we conclude that all the key elements of CE are interconnected. The proposed guide-ACTION (Assessing Circular Transition In Organisations Now)- includes the key elements, databases, tools, and indicators, and is aligned with the CE principles to help the assessment. © 2022 The Author(s)

Grasslands represent canopies with a complex structure where sources and sinks of ammonia (NH3) may coexist at the plant level. Moreover, management practices such as mowing, hay production and grazing may change the composition of the sward and hence the source-sink relationship at the canopy level as well as the interaction with the atmosphere. There is therefore a need to understand the exchange of ammonia between grasslands and the atmosphere better, especially regarding the location and magnitude of sources and sinks. Fluxes of atmospheric NH3 within a grassland canopy were assessed in the field and under controlled conditions using a dynamic chamber technique (cuvette). These cuvette measurements were combined with extraction techniques to estimate the ammonium (NH+4 ) concentration and the pH of a given part of the plant or soil, leading to an estimated ammo- nia compensation point (Cp ). The combination of the cuvette and the extraction techniques was used to identify the poten- tial sources and sinks of NH3 within the different compart- ments of the grassland: the soil, the litter or senescent “litter leaves”, and the functioning “green leaves”. A set of six field experiments and six laboratory experiments were performed in which the different compartments were either added or removed from the cuvettes.The results show that the cuvette measurements agree with the extraction technique in ranking the strength of compartment sources. It suggests that in the studied grassland the green leaves were mostly a sink for NH3 with a compensation point around 0.1–0.4 μg m−3 and   an NH3 flux of 6 to 7 ng m−2 s−1. Cutting of the grass did not increase the NH3 fluxes of the green leaves. The litter was found to be the largest source of NH3 in the canopy, with a Cp of up to 1000μgm−3 NH3 andanNH3 fluxupto90ngm−2 s−1. The litter was found to be a much smaller NH3 source when dried (Cp =160 μg m−3 and FNH3 =35 ng m−2 s−1 NH3 ). Moreover emissions from the litter were found to vary with the relative humidity of the air. The soil was a strong source of NH3 in the period immediately after cutting (Cp =320 μg m−3 and FNH3 =60 ng m−2 s−1 ), which was nevertheless always smaller than the litter source. The soil NH3 emissions lasted, however, for less than one day, and were not observed with sieved soil. They could not be solely explained by xylem sap flow extruding NH+4 . These results indicate that future research on grassland-ammonia relationships should focus on the post-mowing period and the role of litter in interaction with meteorological conditions.

Improving sustainability performance and adapting to circular economy principles in operational business strategies are becoming increasingly prioritized. In this pursuit, the concept of industrial symbiosis (IS) has become increasingly relevant. IS represents a collaborative approach where the interplay of material, residual waste, energy, and infrastructure exchanges aims to yield not only economic and environmental advantages for the participating companies but also substantial societal benefits by using resources more efficiently. Biogas production is such an example, it can reduce greenhouse gas emissions since it can produce heat and electricity, replace renewable fuel for vehicles, or be used as input material for industrial use. The digestate from biogas production can also be used as an effective agricultural fertilizer to replace chemical fertilizers which are produced using fossil energy.

Digital tools and platforms in IS can be used to different extent depending on businesses levels of digital maturity (the extent to which businesses adapt to ongoing digital change and integrate digitalization). Digital tools and platforms hold a central role for developing various advantages in biogas-based IS, but since the digital maturity for IS focusing on biogas production is uncertain, the current efficiency obtained by tools and platforms is unknown. Therefore, through semi-structured interviews and study visits, this study assesses stakeholder collaboration and use of digital tools at five IS sites with biogas production in Sweden. It explores (i) current digital maturity and collaboration characteristics amongst established biogas-based IS, and (ii) needs amongst stakeholders for development of digital tools and platforms to promote digital maturity, monitoring, collaboration, and knowledge exchange in current and future IS structures.

Preliminary results of the on-going study show that the use of digital tools varies depending on the character and size of resource flows that are included in the collaboration, and due to the internal digital maturity of the involved companies. In general, the use of digital tools for stakeholder interaction is on low or medium level, in which manual handling is required and little is automated. This complies with the sites being relatively small, and the number of stakeholders involved are relatively few. Moreover, the preliminary results show that the interest of future development of digital tools is found to be related to business development and expanded market opportunities through diversified raw material use, increased production, and new distribution channels. In addition, a demand of digital platforms for exchange of experience and competence supply has been identified.

Stomatal ammonia compensation points (χs) of grass species on a mixed fertilized grassland were determined by measurements of apoplastic [NH4+] and [H>+] in the field. Calculated χs values were compared with in-canopy atmospheric NH3 concentration (χa) measurements.

Leaf apoplastic [NH4+] increased by a factor of two from the lowest level in the canopy to the top level. Bulk leaf [NH4+] and especially [NO3−] slightly increased at the bottom of the canopy and these concentrations were very high in senescent plant litter. Calculated χs values were below atmospheric χs at all canopy levels measured, indicating that the grassland was characterized by NH3 deposition before cutting. This was confirmed by the χa profile, showing the lowest χa close to the ground (15 cm above soil surface) and an increase in χa with canopy height. Neither χs nor χa could be measured close to the soil surface, however, the [NH4+] in the litter material indicated a high potential for NH3 emission.

A diurnal course in apoplastic [NH4+] was seen in the regrowing grass growing after cutting, with highest concentration around noon. Both apoplastic and tissue [NH4+] increased in young grass compared to tall grass. Following cutting, in-canopy gradients of atmospheric χa showed NH3 emission but since calculated χs values of the cut grass were still lower than atmospheric NH3 concentrations, the emissions could not entirely be explained by stomatal NH3 loss. High tissue [NH4+] in the senescent plant material indicated that this fraction constituted an NH3 source. After fertilization, [NH4+] increased both in apoplast and leaf tissue with the most pronounced increase in the former compared to the latter. The diurnal pattern in apoplastic [NH4+] was even more pronounced after fertilization and calculated χs values were generally higher, but remained below atmospheric [NH3].

As companies and other organizations increasingly recognize society’s demand for greater social and environmental sustainability, university and college business schools have responded with new pedagogic approaches. Business schools have begun to offer courses in business models and business model innovation that focus not only on profit-normative goals but also on social and environmental goals. This paper describes an Experiential Workshop for university undergraduates in which the Service-Learning pedagogic approach is taken and Flourishing Business Canvas is applied as a tool for collaborative visual business modelling. In the Workshop, the students work with business model innovation for a biogas production cooperative of farmer-members in southern Sweden. The students take the role of problem-owners and problem-solvers as they co-create new business models ideas for the cooperative. The paper presents the students’ achievement of three Learning Objectives as they engage in meaningful, “real-world” simulations with a high degree of autonomy that allows them to combine their theoretical knowledge with practice. Implications for educators who wish to test the Experiential Workshop in their classrooms are proposed. The paper concludes with the suggestion that Education for Flourishing is a useful expansion of Education for Sustainable Development. © 2017 Elsevier Ltd. All rights reserved.

Exposure of oilseed rape (Brassica napus) plants to increasing leaf temperatures between 15°C and 25°C increased photorespiratory NH4+ production from 0.7 to 3.5 µmol m-2 s-1. Despite the 5-fold increase in the rate of NH4+ production, the NH4+ concentration in root and leaf tissue water and xylem sap dropped significantly, whereas that in the leaf apoplastic fluid remained constant. The in vitro activity of glutamine synthetase (GS) in both leaves and roots also increased with temperature and in all cases substantially exceeded the observed rates of photorespiratory NH4+ production. The surplus of GS in oilseed rape plants was confirmed using GS2 antisense plants with 50% to 75% lower in vitro leaf GS activity than in the wild type. Despite the substantial reduction in GS activity, there was no tendency for antisense plants to have higher tissue NH4+ concentrations than wild-type plants and no overall correlation between GS activity and tissue NH4+ concentration was observed. Antisense plants exposed to leaf temperatures increasing from 14°C to 27°C or to a trifold increase in the O2 to CO2 ratio did not show any change in steady-state leaf tissue NH4+ concentration or in NH3 emission to the atmosphere. The antisense plants also had similar leaf tissue concentrations of glutamine, glycine, and serine as the wild type, whereas glutamate increased by 38%. It is concluded that photorespiration does not control tissue or apoplastic levels of NH4+ in oilseed rape leaves and, as a consequence, that photorespiration does not exert a direct control on leaf atmosphere NH3 fluxes.

The influence of various nitrogen (N) and sulphur (S) forms on the uptake of manganese (Mn) in young spring barley (Hordeum vulgare L cv Golf) plants was examined in both a hydroponic system and in a soil-based system. The soil was a typical Danish Mn-deficient soil viz. a sandy loam soil developed on old marine sediments. Plants growing in solution culture with NO3– as the only N source had a higher Mn uptake than plants receiving mixtures of NO3– and NH4+. These findings were opposite to the results obtained in the soil-based experiments, where plants fertilized with NO3– as the only N source accumulated much less Mn than plants fertilized with NH4+. Combining the results of these experiments confirmed that NH4+ acted as a powerful antagonist to Mn2+ during uptake but that this antagonistic effect was more than compensated for by the influence of NH4+ in reducing plant-unavailable Mn(IV) to plant-available Mn(II) in the soil. Furthermore the soil experiments showed that fertilizers containing sulphur in the form of reduced S (thiosulphate) had a strong mobilizing effect on Mn, and enabled the plants to accumulate large amounts of Mn in the biomass compared with oxidized S (sulphate). Thus, fertilization with thiosulphate may be very effective in alleviating Mn-deficiency in soils developed on old marine sediments where Mn availability is limiting plant growth.

Denna rapport är en del av utvärderingen av landsbygdsprogrammet 2007–2013. Fyra grupper med forskare från universitet och högskolor har gjort slututvärderingen. Den publiceras i fyra delrapporter varav detta är en. Frågor som handlar om hela programmet besvaras huvudsakligen i delrapport IV. Frågor om enskilda åtgärder besvaras i de tre andra delrapporterna. En översikt av vilka frågor som besvaras i vilken rapport finns på följande sidor.

Slututvärderingen görs för att besvara EU-gemensamma och specifika svenska utvärderingsfrågor om vilka effekter programmet har haft, i vilken utsträckning det har bidragit till att uppfylla målen och hur effektivt detta har gjorts.

Utvärderingssekretariatet vid Jordbruksverket ansvarar för att de svenska EU-programmen där Jordbruksverket är förvaltande myndighet blir utvärderade. Det innebär att utvärderingssekretariatet beställer och genomför utvärderingar av landsbygdsprogrammet, havs- och fiskeriprogrammet samt programmet för lokalt ledd utveckling inom regionalfonden och socialfonden. Programmen utvärderas dels var för sig men också tillsammans. Utvärderingarna görs i relation till målen i programmen och de övergripande EU 2020-målen.

De flesta utvärderingarna genomförs av externa aktörer. Vi tar hjälp av forskare för att kvalitetsgranska rapporterna innan de publiceras. I slutet av rapporterna finns ett utlåtande från granskarna. Rapporterna publiceras i en särskild rapportserie och rapportförfattarna är ansvariga för slutsatserna. Slutsatserna utgör inte Jordbruksverkets officiella ståndpunkt.

/Utvärderingssekretariatet vid Jordbruksverket

As government officials, policymakers, and the general public increasingly express their concern about global warming caused by greenhouse gas emissions, scientists search for alternative sources of vehicle fuel and electric power. One sustainable energy source that shows considerable promise is biogas produced from organic waste. For various reasons, biogas plants in Sweden struggle with profitability. This is especially true for agricultural biogas plants. Suggestions on how to deal with this problem include the use of business model innovation (BMI) to develop agricultural networks and to implement new strategies for arranging, producing, and marketing farm-produced biogas. This qualitative study, influenced by grounded theory, identifies and examines the success factors in an agricultural network in which biogas is produced at four farms in Sweden with distribution by pipeline to a refinery for purification and conversion to vehicle fuel. Fourteen interviews were conducted with various individuals in this network: farmers, a local politician, municipal employees, and external consultants. Of the six success factors identified in the network for farm-produced biogas, the long-term perspective on profitability was found most important. The six factors were used to create a conceptual business model framework for such networks that adds new value propositions while retaining the original value propositions. We propose that long-term government subsidies and other incentives can make farm-produced biogas profitable, not only in social and environmental terms but also in economic terms. Our main conclusion is that BMI can be used to create public-private networks that invest in farm-based biogas production. Such investments can stimulate rural development and provide new business possibilities for SMEs in the agricultural sector. This study also shows that BMI that takes a long-term perspective can result in high-value environmental and social benefits as well as financial profitability.

Farm-based biogas production is a promising renewable energy technology with the potential for creating sustainable economic, environmental, and social value. However, Swedish farmers engaged in this activity struggle to turn a profit because of high-investment costs and severe price competition with fossil fuels. One way to address this situation is to re-organize the activity by innovating the business model (BM) towards sustainability. In this study, a team of researchers took an action research approach that proposed solutions for the financial difficulties at a farm cooperative that intended to develop its farm-based biogas production. Two participatory workshops (including researchers, producers, students, and consultants) were conducted using the sustainable business-modelling tool called the Flourishing Business Canvas (FBC). Based on the 215 ideas developed in the workshops, five sustainable BM prototypes were created. These five prototypes form the basis of an approach for initiating the development of a network-level BM for sustainability that highlights its superiority over a single-firm BM. The network-level BM’s main advantage in the farm-based biogas context is its strong focus on stakeholder collaboration that supports the development of a stakeholder business case for sustainability. Overall, this study highlights the usefulness of the network concept in the practice of sustainable BM development. Collaborative business modelling for developing network-level BMs that address environmental and social problems for and with stakeholders can be an effective way to increase long-term financial profit and promote the growth of a firm, a network, or an industry. © 2018 The Author(s)

In recent years in Sweden, interest has grown concerning the possibilities of biogas production from organic waste. This interest reflects a general concern over environmental sustainability in society. However, given the lack of financial backing and the competition of other energy producers, few Swedish biogas plants have been profitable. This is particularly the situation with farm-based biogas producers. One response to this problem in the farm-based biogas industry is to engage in business model innovation that can lead to new ways of organizing business structures and activities. This qualitative study, which takes an action research approach, explores the early phases (initiation and ideation) of the business model innovation process for sustainability at a biogas-producing farm cooperative in southern Sweden. The main activities and the actors who are central to the execution of these activities are identified in six sub-phases. The paper describes two Flourishing Business Canvas workshops in which the participants were the researchers, members of the farm cooperative, external consultants, and university students. This study contributes theoretically to the literature with its detailed examination of the early phases of the business model innovation process for sustainability. It also contributes to practice with its conceptual model that demonstrates how biogas producers and farm managers can innovate and transform their current business models towards sustainability in order to improve competitiveness and long-term profitability. (C) 2017 Elsevier Ltd. All rights reserved.

The herbicide glufosinate, which is also called phosphinothricin (PPT), is known to inhibit glutamine synthetase and thus causes a blockage of ammonium (re)assimilation in plants. The objective of the present study was to test whether application of this herbicide results in an ammonia volatilization from the plants and to quantify nitrogen loss via ammonia emission. Four different weed species (Chenopodium album, Echinocloa crus-galli, Solanum nigrum, Tripleurospermum inodorum) were grown as monocultures in the greenhouse and treated with PPT when their canopies covered the soil. In the first experiment, whole shoot samples were taken during the following days and analysed for ammonium, pH and total nitrogen content. In the second experiment, apoplastic pH and ammonium concentration of the leaves were measured after herbicide application and used for the calculation of Γ-values (ratio between NH4+ and H+ concentration), the stomatal NH3 compensation point and the canopy net NH3 flux with a soil vegetation atmosphere transport (SVAT) model.

Herbicide treatment caused a rapid increase in shoot ammonium concentration and the ammonium portion of the plant total nitrogen ranged from 0.6 to 0.9% and from 17 to 44% before and after PPT application, respectively. S. nigrum showed a strong increase in ammonium portion (35%) followed by a decrease (20%), which may have resulted from ammonia volatilization. The difference in total shoot nitrogen content per ground area at the start and 2 weeks after PPT application averaged for the three C3 weed species to a nitrogen loss of ca. 0.4 g N m−2 or approximately 13% of the total nitrogen in the weed canopy. Analysis of the apoplastic fluid yielded an increase in ammonium concentration and a pH decrease after an initial increase on day 1 after the PPT treatment. In order to evaluate the potential for ammonia loss, the Γ-value was calculated for both apoplastic and tissue water. S. nigrum showed the most dramatic increases in both apoplastic and tissue–water Γ-values 4 days after PPT treatment. The calculated stomatal NH3 compensation point was strongly elevated after PPT treatment. However, temporal changes of apoplastic pH and ammonium concentration varied between the species and the modelled ammonia emission ranged from 0.03 to 0.09 g N m−2. It is concluded that PPT application results in an ammonia emission of ca.

Efforts to mitigate greenhouse gas (GHG) emissions are receiving increased attention among governmental and commercial actors. In recent years, the interest in paludiculture, i.e. the use of rewetted peatlands, has grown because of its potential to reduce GHG emissions by stopping soil decomposition. Moreover, cultivating wetland plants on rewetted peatlands for  bioenergy production that replaces fossil fuels in the transport sector, can contribute to additional GHG emission reductions. In this study, an analysis of literature data was conducted to obtain data on GHG emissions (CO2 and CH4) and biomass production from rewetted peatlands cultivated with two different wetland plant species: Phragmites australis (Pa) and Typha latifolia (Tl). In  addition, a  biogas experiment was carried out to investigate the biomethane yield of Pa and Tl biomass, and the reduction of global warming potential (GWP) by using biomethane as vehicle fuel. The results show that peatland rewetting can be an important measure to mitigate the GWP as it reduces GHG emissions from the soil, particularly on a 100-year timescale but also to some extent on a 20-year timescale. More specifically, rewetting of 1 km2 of peatland can result in  a  GWP reduction corresponding to  the  emissions from ±2600 average sized petrol cars annually. Growing Pa on rewetted peatlands reduces soil GHG emissions more than growing Tl, but Pa and Tl produced similar amounts of biomass and biomethane per land area. Our study concludes that Pa, because of a more pronounced GWP reduction, is the most suitable wetland plant to cultivate after peatland rewetting. © 2020 The Author(s). Published by Elsevier Ltd.

The exchange of ammonia between crop canopies and the atmosphere depends on a range of plant parameters and climatic conditions. However, little is known about effects of management factors. We have here investigated the stomatal ammonia compensation point in response to cutting and fertilization of a grass sward dominated by Lolium perenne. Tall grass had a very low NH3 compensation point (around 1 nmol mol−1), reflecting the fact that leaf nitrogen (N) concentration was very low. During re-growth after cutting, leaf tissue concentrations of NO3−, NH4+, soluble N and total N increased along with apoplastic NH4+ concentrations. In contrast, apoplastic pH decreased resulting in largely unaltered NH3 compensation points. Nitrogen fertilization one week after cutting caused the apoplastic NH4+ concentration of the newly emerging leaves to increase dramatically. The NH3 compensation point peaked between 15 and 25 nmol mol−1 the day after the fertiliser was applied and thereafter decreased over the following 10 days until reaching the same level as before fertilisation. Ammonium concentrations in leaf apoplast, bulk tissue and litter were positively correlated (P=0.001) throughout the experimental period. Bulk tissue NH4+ concentrations, total plant N and soil NH4+ concentrations also showed a positive correlation. A very high potential for NH3 emission was shown by the plant litter.

Species diversity in grasslands usually declines with increasing input of nitrogen from fertilizers or atmospheric deposition. Conversely, species diversity may also impact the build-up of soil and plant nitrogen pools. One important pool is NH3/NH4+ which also can be exchanged between plant leaves and the atmosphere. Limited information is available on how plant-atmosphere ammonia exchange is related to species diversity in grasslands. We have here investigated grass species abundance and different foliar nitrogen pools in 4-year-old intensively managed grassland. Apoplastic pH and NH4+ concentrations of the 8 most abundant species (Lolium perenne, Phleum pratense, Festuca pratensis, Lolium multiflorum, Poa pratensis, Dactylis glomerata, Holcus lanatus, Bromus mollis) were used to calculate stomatal NH3 compensation points. Apoplastic NH4+ concentrations differed considerably among the species, ranging from 13 to 117 μM, with highest values in Festuca pratensis. Also apoplastic pH values varied, from pH 6.0 in Phleum pratense to 6.9 in Dactylis glomerata. The observed differences in apoplastic NH4+ and pH resulted in a large span of predicted values for the stomatal NH3 compensation point which ranged between 0.20 and 6.57 nmol mol−1. Three species (Lolium perenne, Festuca pratensis and Dactylis glomerata) had sufficiently high NH3 compensation point and abundance to contribute to the bi-directional NH3 fluxes recorded over the whole field. The other 5 grass species had NH3 compensation points considerably below the atmospheric NH3 concentration and were thus not likely to contribute to NH3 emission but only to NH3 uptake from the atmosphere. Evaluated across species, leaf bulk-tissue NH4+ concentrations correlated well (r2=0.902) with stomatal NH3 compensation points calculated on the basis of the apoplastic bioassay. This suggests that leaf tissue NH4+ concentrations combined with data for the frequency distribution of the corresponding species can be used for predicting the NH3 exchange potential of a mixed grass sward.

Hästgödsel som substrat för biogasproduktion undersöktes i tre rötningsförsök. Resultaten från dessa tillsammans med olika strömedels för- och nackdelar, transportlogistik för gödseln och ekonomiska överväganden har bedömts med syfte att kunna presentera en helhetslösning för hästägare och hästföretag.

Rötningsförsöken visade att hästgödsel kan samrötas med nöt-, svin-och hönsgödsel med godtagbar metanproduktion. Svingödsel har ett högt näringsinnehåll (framförallt kväve) som kompletterar den näringsfattiga hästgödseln på ett bra sätt samtidigt som den är mer flytande och därmed gör hästgödseln mer pumpbar. Både torv och halmpellets kan användas som strömedel med godtagbar metanproduktion. Kväveinnehållet blir lägre och kol-kvävekvoten högre med torv jämfört med halmpellets men halmpellets har praktiska och ekonomiska fördelar framför torv. Färsk hästgödsel producerade mer metan med torv än med halmpellets, men efter lagring i en månad producerade hästgödseln med halmpellets mer metan än torvgödseln. Lagring i två månader var däremot negativt för metanproduktionen från båda hästgödsel/strömedel kombinationerna.

Sammantaget leder resultaten till en möjlig modell för hästgödselns utnyttjande för biogasproduktion innefattande samrötningssubstrat, strömedel, lagring, transport och ekonomi som kan rekommenderas för hästnäringen.

Flera miljömässiga fördelar med en ökad biogasrötning av hästgödsel kan lyftas fram. Produktion av ett förnybart bränsle, minskade klimatgasutsläpp och näringsförluster samt ett bättre kretsloppstänkande är några uppenbara sådana.

Rapporten ser stora möjligheter för utnyttjande av denna potential men pekar också på behovet av mer forskning och utveckling inom området.

CO₂ emissions to the atmosphere were studied in a fertilized sandy agricultural soil with and without a catch crop sown into the main crop. The catch crop was grown primarily with the purpose to decrease N-leaching but this study also wanted to find out if the catch crop could have an effect in a climate change perspective. Plots with catch crop showed decreased CO₂ emissions from the soil. Since previous results have shown that catch crops effectively decrease N-leaching we recommend growing catch crops as an effective measure for helping both the climate and the eutrophication issue. Seasonal variations in CO₂ emissions were pronounced with maximum emissions from the fertilized agricultural soil in June and from an adjacent unmanaged grassland in August. From the plot with catch crop emissions decreased in July and August but somewhat increased later in the autumn. Fertilized agricultural soil showed a within-soil CO₂ sink after harvest, i.e. within-soil CO₂ uptake. Availability of NH₄⁺ or NO₃^- in the soil seems to influence the within-soil CO₂ sink, with NH₄⁺ enforcing the sink while the same amount of NO₃^- instead increased CO₂ emissions. © 2015 BioOne All rights reserved

Apoplastic and bulk tissue concentrations of NH4+ and H+ were measured during senescence of intact (attached) and excised ryegrass (Lolium perenne) leaves differing in nitrogen and carbon status. The potential for NH3 emission from the senescing leaves was estimated on the basis of the ratio between [NH4+] and [H+], designated the Γ-value, in apoplastic solution and bulk tissue.

Attached leaves with visual symptoms of senescence showed two to three times higher [NH4+] and 0.5–1 unit lower pH in both apoplastic solution and bulk tissue extracts compared with green leaves. The Γ-values were, in all cases, low in attached leaves, ranging from 20 to 300 in the apoplastic solution and 500–900 in the bulk tissue.

In excised leaves with high nitrogen status and low C : N ratio (≈ 10), apoplastic [NH4+] increased from around 40 µm to 2 mm after senescence in darkness for 4–9 d. Bulk tissue water [NH4+] increased in the same period to > 30 mm. Apoplastic Γ-values were in all cases < 1000, while bulk tissue Γ-values increased dramatically and reached more than 60 000 in high-nitrogen leaves.

Ammonia compensation points predicted on the basis of apoplastic [NH4+] and pH in senescing leaves with high-nitrogen status reached 6–8 nmol mol-1 air. Consequently, senescing leaves may constitute a significant source of atmospheric NH3.

Short- and long-term responses of inorganic N pools and plant-atmosphere NH3 exchange to changes in external N supply were investigated in 11-week-old plants of two grass species, Lolium perenne and Bromus erectus, characteristic of N-rich and N-poor grassland ecosystems, respectively. A switch of root N source from NO3- to NH4+ caused within 3 h a 3- to 6-fold increase in leaf apoplastic NH4+ concentration and a simultaneous decrease in apoplastic pH of about 0.4 pH units in both species. The concentration of total extractable leaf tissue NH4+ also increased two to three times within 3 h after the switch. Removal of exogenous NH4+ caused the apoplastic NH4+ concentration to decline back to the original level within 24 h, whereas the leaf tissue NH4+concentration decreased more slowly and did not reach the original level in 48 h. After growing for 5 weeks with a steady-state supply of NO3- or NH4+, L. perenne were in all cases larger, contained more N, and utilized the absorbed N more efficiently for growth than B. erectus, whereas the two species behaved oppositely with respect to tissue concentrations of NO3-, NH4+, and total N. Ammonia compensation points were higher for B. erectus than for L. perenne and were in both species higher for NH4+- than for NO3--grown plants. Steady-state levels of apoplastic NH4+, tissue NH4+, and NH3 emission were significantly correlated. It is concluded that leaf apoplastic NH4+ is a highly dynamic pool, closely reflecting changes in the external N supply. This rapid response may constitute a signaling system coordinating leaf N metabolism with the actual N uptake by the roots and the external N availability.

A new biophysical model SURFATM-NH3, simulating the ammonia (NH₃) exchange between terrestrial ecosystems and the atmosphere is presented. SURFATM-NH3 consists of two coupled models: (i) an energy budget model and (ii) a pollutant exchange model, which distinguish the soil and plant exchange processes. The model describes the exchanges in terms of adsorption to leaf cuticles and bi-directional transport through leaf stomata and soil. The results of the model are compared with the flux measurements over grassland during the GRAMINAE Integrated Experiment at Braunschweig, Germany. The dataset of GRAMINAE allows the model to be tested in various meteorological and agronomic conditions: prior to cutting, after cutting and then after the application of mineral fertilizer. The whole comparison shows close agreement between model and measurements for energy budget and ammonia fluxes. The major controls on the ground and plant emission potential are the physicochemical parameters for liquid-gas exchanges which are integrated in the compensation points for live leaves, litter and the soil surface. Modelled fluxes are highly sensitive to soil and plant surface temperatures, highlighting the importance of accurate estimates of these terms. The model suggests that the net flux depends not only on the foliar (stomatal) compensation point but also that of leaf litter. SURFATM-NH3 represents a comprehensive approach to studying pollutant exchanges and its link with plant and soil functioning. It also provides a simplified generalised approach (SVAT model) applicable for atmospheric transport models.

During 2013, an evaluation of all the research conducted at Halmstad University was carried out. The purpose was to assess the quality of the research, coproduction, and collaboration in research, as well as the impact of the research. The evaluation was dubbed the Assessment of Research and Coproduction 2013, or ARC13. (Extract from Executive Summary)

Much controversy exists about whether or not NH+4 is translocated in the xylem from roots to shoots. In this paper it is shown that such translocation can indeed take place, but that interference from other metabolites such as amino acids and amines may give rise to large uncertainties about the magnitude of xylem NH+4 concentrations. Elimination of interference requires sample stabilization by, for instance, formic acid or methanol. Subsequent quantification of NH+4 should be done by the OPA-fluorometric method at neutral pH with 2-mercaptoethanol as the reducing agent since this method is sensitive and reliable. Colorimetric methods based on the Berthelot reaction should never be used, as they are prone to give erroneous results. Significant concentrations of NH+4, exceeding 1 mM, were measured in both xylem sap and leaf apoplastic solution of oilseed rape and tomato plants growing with NO-3 as the sole N source. When NO-3 was replaced by NH+4, xylem sap NH+4 concentrations increased with increasing external concentrations and with time of exposure to NH+4. Up to 11% of the translocated N was constituted by NH+4. Glutamine synthetase (GS) incorporates NH+4 into glutamine, but root GS activity and expression were repressed when high levels of NH+4 were supplied. Ammonium concentrations measured in xylem sap sampled just above the stem base were highly correlated with NH+4 concentrations in apoplastic solution from the leaves. Young leaves tended to have higher apoplastic NH+4 concentrations than older non-senescing leaves. The flux of NH+4 (concentration multiplied by transpirational water flow) increased with temperature despite a decline in xylem NH+4 concentration. Retrieval of leaf apoplastic NH+4 involves both high and low affinity transporters in the plasma membrane of mesophyll cells. Current knowledge about these transporters and their regulation is discussed.

A major international experiment on ammonia (NH3) biosphere-atmosphere exchange was conducted over intensively managed grassland at Braunschweig, Germany. The experimental strategy was developed to allow an integrated analysis of different features of NH3 exchange including: a) quantification of nearby emissions and advection effects, b) estimation of net NH3 fluxes with the canopy by a range of micrometeorological measurements, c) analysis of the sources and sinks of NH3 within the plant canopy, including soils and bioassay measurements, d) comparison of the effects of grassland management options on NH3 fluxes and e) assessment of the interactions of NH3 fluxes with aerosol exchange processes. Additional technical objectives included the inter-comparison of different estimates of sensible and latent heat fluxes, as well as continuous-gradient and Relaxed Eddy Accumulation (REA) systems for NH3 fluxes. The prior analysis established the spatial and temporal design of the experiment, allowing significant synergy between these objectives. The measurements were made at 7 measurement locations, thereby quantifying horizontal and vertical profiles, and covered three phases: a) tall grass canopy prior to cutting (7 days), b) short grass after cutting (7 days) and c) re-growing sward following fertilization with ammonium nitrate (10 days). The sequential management treatments allowed comparison of sources-sinks, advection and aerosol interactions under a wide range of NH3 fluxes. This paper describes the experimental strategy and reports the grassland management history, soils, environmental conditions and air chemistry during the experiment, finally summarizing how the results are coordinated in the accompanying series of papers.

Improved data on biosphere-atmosphere exchange are fundamental to understanding the production and fate of ammonia (NH₃) in the atmosphere. The GRAMINAE Integrated Experiment combined novel measurement and modelling approaches to provide the most comprehensive analysis of the interactions to date. Major intercomparisons of micrometeorological parameters and NH₃ flux measurements using the aerodynamic gradient method and relaxed eddy accumulation (REA) were conducted. These showed close agreement, though the REA systems proved insufficiently precise to investigate vertical flux divergence. Grassland management had a large effect on fluxes: emissions increased after grass cutting (−50 to 700 ng m^-2 s^-1 NH₃) and after N-fertilization (0 to 3800 ng m^-2 s ^-1) compared with before the cut (−60 to 40 ng m^-2 s ^-1). © Author(s) 2009.

Global warming along with energy demand and rising prices of natural energy resources have motivated studies to find some renewable and clean energy. The use of algae as the third-generation biofuel can avoid the competition for farmland, and algae can be considered as a potential future source of renewable energy. Algae can be used for biogas production through anaerobic digestion (AD). Fucus vesiculosus and Fucus serratus are the two dominating species of brown seaweed growing in the Baltic Sea in the southwest of Sweden. Pretreatment can significantly affect the biogas production because hydrolysis of the algae cell wall structure is a rate-limiting step in the AD process. In this study, four different pretreatments: mechanical, microwave (600 W, 2 min), ultrasonic (110 V, 15 min), and microwave combined with ultrasonic (600 W, 2 min; 110 V, 15 min) were applied to the seaweed and then codigested with a biogas plant leachate. The aim of this study was to investigate methane yields from AD after these pretreatments. The results showed that when compared with only mechanical pretreatment, the ultrasonic, ultrasonic combined with microwave, and microwave pretreatments could obtain increased cumulative methane yields of 167, 185, and 156%, respectively. The combined pretreatment showed a maximum methane yield of 260 mL/g·of volatile solids after 20 days of digestion. The ultrasonic combined with microwave pretreatment showed a significant improvement in methane yield when compared with the mechanical pretreatment. Copyright © 2019 American Chemical Society