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Precision hos ett digitalt gallringshjälpmedel
Get PDFAtt göra en bra planering är väsentligt för dagens skogsbruk. Genom att förbereda så mycket som möjligt med datorn blir fältarbetet effektivt. Gallringsapp som SLU har utvecklat är ett hjälpmedel för att bestämma ett uttag på provytenivå (20×20 meter) i kvadratmeter med hjälp av laserdata. Hjälpmedlet är framtaget för både maskinförare och planering. Södra skogsägarna utför varje år ett antal uppföljningar av gallrade bestånd för att utvärdera kvaliteten på sitt arbete. Med detta material har en jämförelse gjorts mellan gallringsappdatan och gallringsuppföljningsdata. Fyra bestånd har följts upp av rapportskrivaren med 7,98 meter provytor jämfört med 5,64 meter som Södra använder sig av. Genom en jämförelse av grundytan för gallringsappen och gallringsuppföljningen på provytenivå är differensen för hög för att fastställa ett samband på provytenivå. På beståndsnivå är sambandet tydligare och det går att fastställa en korrelation mellan uppföljningen och gallringsappen. Fem bestånd utskiljer sig genom en underskattning av gallringsappen med okänd anledning, eventuellt på grund av för små provytor i gallringsuppföljningens 100 m2 och 200m2 jämfört med gallringsappens 1 600 m2. Med för små provytor är risken stor att lokala variationer som en lucka påverkar resultatet avsevärt. För framtida studier rekommenderas en uppföljning med 20×20 meter stora provytor synkade med gallringsappen.A good planning is a key factor for modern forestry. By preparing as much as possible from the computer, the field work will be effective. Thinning application that is developed by SLU is an aid to decide the thinning withdrawal in small sample plots, 20×20 meters by using laser data.
The aid purpose is to help both forestry machine operators and planning. Södra Forestry owners is every year doing an evaluation on the thinned forests to guarantee the quality of the work. With the data from the evaluation a comparison has been made between the thinning app and the follow up. Four stands with a circle radius of 7,98 meter were used and the remaining 13 stands, 5,64 meter circle radius were used. By comparing the basal area of both samples on sample area level, a conclusion has been drawn that the difference is too high to determine a connection. On stand level the results are that a connection between the thinning follow up and the thinning app can be established. Five stands differentiate by an underestimation of the basal area in the thinning app with unknown reasons why. Possibly a reason is the smaller sample area of the thinning follow up, 100 square meters compared to the thinning apps 1 600 square meters. By using too small sample plots a local variation as a gap affects the results greatly. For future studies a recommendation is to use bigger sample plots, 20×20 meters synced with the thinning application
Deliberation and sustainability
Get PDFAs the effects of climate change intensifies, the tension between slow democratic processes and the need for urgent change towards sustainability is becoming more evident. This thesis aims to investigate how policymakers understand the relationship between deliberation and sustainability through a frame analysis and to identify tensions between the frames. The data consists of two policy documents, two interviews with politicians, and one interview with an official. The results are three frames; the system change frame, the participation frame, and the conflict frame. In the system change frame, deliberation is perceived to induce democratic engagement among citizens, which in turn will lead to structural change. This structural change is believed to have positive outcomes on ecological and social sustainability. The participation frame understands deliberation as a tool to increase social sustainability by emphasising the potential to increase diverse citizen democratic engagement, without necessarily resulting in system change. In the conflict frame, the controversy around issues related to sustainability is highlighted, and deliberation is seen as a tool to deal with conflicts constructively. A tension between the system change and participation frames arises in how radical a system change can be when deliberation, according to the participation frame, cannot guarantee sustainable outcomes. Another tension is highlighted between the system change and conflict frames, where the purpose of deliberation is understood differently. Further research could investigate how the tensions can be managed in practice and to study how practitioners and citizens understand the relationship between deliberation and sustainability to deepen the theoretical knowledge
Lärkens framtid i svensk förädlingsindustri
Get PDFVal av trädslag vid skogsföryngring kan ha en stor inverkan på skogsägandets lönsamhet då olika trädslag har olika egenskaper och preferenser gällande exempelvis jordmån och klimat. Felaktiga val av trädarter kan också leda till skador på grund av storm, brand och biotiska skadegörare. Det är således av nytta för intressenterna inom skogsbruket att undersöka alternativa brukningssätt för att minska sina kostnader relaterade till dessa faktorer.
Lärken är ett trädslag som är relativt nytt och mycket begränsat i sin utbredning inom det svenska skogsbruket. I Sverige är det främst två varianter av lärk som odlas, den sibiriska lärken (Larix sibirica) och hybridlärken (Larix X marchlinsii). Båda har en omloppstid som är avsevärt mycket kortare än tall (Pinus sylvestris) och gran (Picea Abies) vilket innebär att samma virkesmängd kan skördas oftare. Virket innehar egenskaper som liknar tallen (Pinus sylvestris), framför allt gällande beständighet mot röta.
Syftet med denna studie är att genom kvalitativa intervjuer med representanter för svenska skogsindustrier och vetenskaplig litteratur skapa en tydligare bild av de framtidsprognoser som svenska skogsindustrier har gällande lärken som produktionsträdslag. Studien avgränsar sig till att undersöka den sibiriska lärken och hybridlärken samt att endast undersöka dessa inom Sverige. Framtiden avgränsas till att motsvara en omloppstid för en lärk, det vill säga 40 år.
Resultatet visade att majoriteten av de tillfrågade företagen inte såg någon stadigt ökande trend för lärkens roll inom skogsindustrin, bortsett från enstaka tillökningsfaser. Däremot ställde sig majoriteten av dessa företag försiktigt positiva till trädslaget och avfärdade det inte som ett framtida växande alternativ.
De slutsatser som gick framgick av studien var att det inte fanns någon brist på skogsindustrier som var villiga att köpa och förädla det befintliga svenska lärkvirket. En gemensamt begränsande faktor ur en förädlingssynpunkt var dock att det ännu bedömdes finnas så lite lärk planterat i Sverige att endast ett fåtal mindre industrier kunde bygga en hållbar produktion som helt riktade in sig mot lärk. Detta gav lärken något av en biroll inom svensk skogsförädling. Generellt bedömdes lärken dock ha en blygsamt ökande roll inom svensk skogsindustri och ett intresse för ökad forskning inom ämnet var framträdande.The choice of species that a felled forest is reafforested with can have a great impact on the profitability of the forest ownership as different species have different qualities and preferences regarding the type of soil and climate. Improper choices of tree species can also lead to higher damages due to storm, fire, and biotic pests. It is therefore of interest for the parties within the forestry to examine alternative ways of working to minimize their costs related to these factors.
The larch is a tree species that is relatively new and very limited in its usage within the Swedish forest sector. In Sweden, it is prominently two subspecies of larch that are being grown, the Siberian larch (Larix sibirica), and the hybrid larch (Larix X marchlinsii). Both have a regrowth period that is significantly shorter than that of Scots pine (Pinus sylvestris) and Norway spruce (Picea abies) meaning that the same amount of wood can be harvested more often. Its wood has qualities that resemble the Scots pine, primarily regarding the durability to rot.
This study aims to create a clearer overview of the future prognoses that the Swedish forestry industries have regarding the larch as a production tree. The method is composed of qualitative interviews with representatives from different Swedish forestry industries along with scientific litterature. The study delimits to research only the Siberian larch and the hybrid larch and to only research these within Sweden. The future is defined to equal a regrowth period for a larch, meaning 40 years.
The result showed that most of the consulted companies did not see any clearly rising trend for the larch’s role within the forestry industry, apart from a few separate growth phases. However, most of them still felt cautiously positive to the tree species and did not dismiss it as a growing alternative for the future.
The conclusions that could be drawn from the study was that there was no shortage of forestry industries that were willing to buy and refine the existing Swedish larch wood. A common limiting factor from a refining point of view was that the amount of larch planted in Sweden still was so small that only a few minor industries could build a sustainable production that fully concentrated on lrefining larch. This gave the larch a kind of a subordinate part within Swedish forestry refining. However, overall, the larch was estimated to have a modestly growing part within the Swedish forestry industry and an interest for increased research within the subject was prominent
The Station in the Urban Space : the Landscape Surrounding the Stockholm Underground Station
Get PDFStockholms Stad beskriver i sin översiktsplan att
stadens attraktivitet är viktig, inte bara för Stockholm
utan också för dess funktion som motor för hela Sverige.
Man ser utmaningar kring framtida transportinfrastruktur
- gång, cykel och kollektivtrafik, och
också att stadsbyggandet ska utvecklas ur ett socialt,
hållbart perspektiv, med god kvalitet och god arkitektur.
Man ser också hur det omfattande stadsbyggande
som staden har framför sig blir en möjlighet för
utveckling och förbättring och man ser framför sig en
tät och sammanhållen stad där bebyggelse och grönt
samspelar (Stockholms stad 2018).
Jag ser framför mig hur en uppdaterad bild av hur
det kan vara att spendera tid i stationsområdet kan
bidra till ökat kollektivt resande och leda till en
stadsplanering fokuserad på att minska bilåkandet.
Tunnelbanestationen har ofta en central placering i
stadsmiljön och jag ser en outnyttjad potential, ur ett
socialt och ur ett stadsplaneringsmässigt perspektiv,
för hur stationsomgivningen bättre kan användas.
Jag ville med examensarbetet undersöka och
identifiera tillkortakommanden i miljön runt
Stockholms tunnelbanestationer angående funktion,
sociala aspekter, planering och rumslighet – från
gångtrafikanters och pendlares perspektiv. Jag ville
också generellt diskutera och presentera förslag på
principer som visar hur miljön runt stationer kan gestaltas
på ett mer medvetet sätt för att göras attraktiva
och fungera som sociala mötesplatser integrerade i
stadsmiljön. Slutligen ville jag omsätta principerna i
ett förslag på omvandling av miljön runt tunnelbanestationen
S:t Eriksplan.
Omvandlingen gjorde platsen till en man faktiskt
vill besöka och inte bara en plats som övervägande
används som passage. Platsen interagerar efter omvandlingen
med sin omgivning på ett helt annat sätt
än tidigare. Med nya sittplatser, tillgång till mat och
dryck, skydd från väder och med grönska som både
skapar nya rumsligheter och avskärmar besökare
från omgivande trafik, är platsen nu anpassad för den
gående. De många människor som redan använder
platsen för resande med tunnelbanan skapar goda
förutsättningar för att göra platsen välbesökt. Funktion,
form och färg har justerats så att den mentala
bilden av platsen nu påminner om den av ett torg.
Jag hoppas att examensarbetet kan bidra med kunskap
och idéer om hur stationsomgivningar i stadsmiljö
kan integreras i stadslandskapet och upplevas
som attraktiva platser.Stockholm Stad describes in their overview plan that
the attractiveness of the city is important, not only
to Stockholm, but for the whole country. They see
challenges in future development of transport-infrastructure
– pedestrian, bicycle and public transport,
and also the urban construction to develop with a
social perspective, with quality and good architecture.
They also see how the extensive city planning that
the city has before themselves becomes an opportunity
to improvement and they see a close and cohesive
city where buildings and green interacts (Stockholms
stad 2018).
I believe that an updated image of how it can be
to spend time in the area around stations could
contribute to increased public travelling and to city
planning focused on decreased motoring. Thanks to
the often central strategic location the metro station
has in the city I see an untapped potential for how
the station and its surrounding better could be used,
from a social as well as city planning perspective.
I wanted to examine and identify shortages in settings
around the Stockholm metro stations regarding
function, social aspects, planning and spatiality
– from the pedestrian and travellers point of view.
I also wanted to generally discuss and present suggestions
of principals showing how the environment
around the stations could be designed in a more
consciously way to be made more attractive and
function as social venues integrated in the city. Finally,
I wanted to convert my principals in a proposal for
reshaping of the location around the metro station S:t
Eriksplan.
The reshaping of the location made it a place you
actually want to visit and not only use as a passage.
The place now integrates with its surrounding in a
totally different way than it did before. With new
seating, access to food and drink, protection from
weather and greenery that creates new spatiality’s as
well as protects from surrounding traffic, the place
is now customized for pedestrians. The many people
that already uses the location to travel with the metro
gives a good prerequisite to make the place well
attended. Function, form and color has been adjusted
so that the mental image of the place now resembles
a public square.
I hope that the master thesis can contribute with
knowledge and ideas of how urban station settings
can be integrated in the city landscape and be experienced
as attractive places
Creating, delivering, and capturing value through sustainability
Get PDFAquaculture is one of the fastest-growing food sectors in the world, and the increasing world population is said to only increase the need for more seafood. However, the sustainability of the aquaculture has been questioned recently and measures have been taken to overcome and internalize the negative externalities. These externalities include eutrophication of water bodies, the various impact of wildlife, disease transfer, and water source pollution. With the rising concerns of the open cage aquacultural systems, there has been rising interest in the Recirculating aquaculture systems (RAS) which use a closely controlled environment to grow fish.
One example of this is aquaponics which is defined as an integrated system where two elements of recirculating aquaculture and hydroponics are combined. This system of integration allows some of the shortcomings of aquaculture and hydroponics to be addressed promising to be a sustainable food production method. However, research within the area of aquaponics is mostly focusing on technical perspectives such as the engineering aspect as well as the microbiology. There are few existing commercial aquaponics businesses known in Sweden and very little knowledge about how the aquaponic business model is developed in practice.
The aim of this research is therefore to explore the early development business model of aquaponics in Sweden and how it can be conceptualized as a sustainable business model. A qualitative method was chosen to collect the data where the unit of analysis is individual units. The people that are used as the unit of analysis are individuals with expertise in the field either from research or practice as well as policies that govern this area.
This explorative study of aquaponics found aquaponics to be a promising innovation for sustainable food production and a learning curve in the process of sustainability. However, its growth in Sweden is underdeveloped and a paradox. Understanding this weakness in the growth of aquaponics can help inform policymakers and contributes to the uptake of aquaponics in Sweden. Understanding the BMI of aquaponics has revealed economic viability as a central pillar in the development of innovations for sustainability and the foundation to the development of environmental and social sustainability. These finding questions the balance in importance shown in the literature of the three pillars of sustainability
Porträtt av svenska naturlandskap
Get PDFSvaret på hur vi utforskar, läser, uppfattar och upplever landskap är mångfacetterat och bygger på vår
perceptuella uppfattning och kognitiva förmåga. Genom att ha ett öppet sinne kan man upptäcka de
många olika lager som ett landskap kan innehålla, en mångfald av värden och kvalitéer som initialt kanske
inte är uppenbara. Detta arbete fokuserar på estetiska kvalitéer som vi kan finna i landskap, främst de rumsliga
och visuella.
I arbetet har ett ramverk innehållande ett flertal dokumenterande metoder utvecklats och använts på
ett explorativt sätt för att identifiera och representera rumsliga och visuella kvalitéer i landskapsrum i
naturlandskap. Syftet har varit att använda metoder som skiljer sig åt i sitt utförande, för att dessa ska komplettera
varandra och ge en mer nyanserad bild av landskap. Metoderna baseras på konstnärliga och visuella arbetssätt.
Exkursioner till sex stycken av Sveriges nationalparker; Söderåsen, Store Mosse, Kosterhavet, Abisko, Muddus
och Färnebofjärden genomfördes under arbetets gång. Dessa agerade arenor för våra undersökningar och
valdes ut baserat på geografiskt läge och naturtyp för att ge arbetet en diversitet och spegla de olika uttryck
som kan tänkas finnas i vårt avlånga land.
En ökad förståelse för hur vi upplever landskap, och vilka metoder som kan användas för att dokumentera och
representera landskap på ett adekvat sätt i en mänsklig skala, kan i förlängningen leda till bättre analyser och
slutsatser kring vilka dessa värden och kvalitéer är. Vissa menar att skönheten ligger i betraktarens öga, andra
att skönheten finns inbäddat i objektet eller fenomenet i sig – oberoende av betraktaren. I naturlandskap
verkar det dock finnas en universalitet i svaret gällande vilka de estetiska värdena är. Vår perceptuella förmåga
och estetiska respons underbyggs ofta, både medvetet och omedvetet, av kunskap, vetenskap, känslor och
föreställningar. Evolutionen och vårt gemensamma arv visar sig också spela in. Genom att väga in och ta
hänsyn till allt detta bildar vi oss en uppfattning om vår omgivning. Arbetet visar att svaret på vilka de estetiska
kvalitéerna är beror på alla dessa faktorer, men också på vem du är och vad du har i din ryggsäck.The answer to how we explore, read, perceive and, experience landscapes is multifaceted and are based
on our perceptual understanding and cognitive ability. By having an open mind, one can discover the
many different layers that a landscape can contain, and a diversity of values and qualities that may not
be obvious at first. This work focuses on aesthetic qualities that we can find in landscapes, mainly the spatial
and visual ones.
The work is based on a framework that consists of several methods for natural landscape documentation. These
been further developed and used in an exploratory way to identify and represent spatial and visual qualities
in landscape spaces. The purpose has been to use methods that differ in their design so that these complement
each other and give a more nuanced expression of the landscape. The methods are mainly based on artistic and
visual representation methods. Excursions to six Swedish National Parks were conducted between 14/5-11/9,
2020; Söderåsen, Store Mosse, Kosterhavet, Abisko, Muddus and, Färnebofjärden. These acted as arenas for our
surveys and were selected based on geographical location and landscape type to give the work diversity and
reflecting the different expressions that may exist in our elongated country.
An increased understanding of how we experience landscapes, and what methods can be used to document
and represent landscapes in an adequate way on a human scale, can in the long run lead to better analyzes
and conclusions about what these values and qualities are. Some believe that beauty lies in the eye of the
beholder, others believe that beauty is embedded in the object or phenomenon itself – independent of the
beholder. In natural landscapes, however, there seems to be a universality in the answer regarding what the
aesthetic values are. Our perceptual ability and aesthetic response are often supported, both consciously and
unconsciously, by knowledge, science, emotions, and imagination. Evolution and our common heritage also
prove to play a role. By weighing in and taking into account all this, we form an idea of our surroundings. The
work shows that the answer to what the aesthetic qualities are depends on all these factors, but also on who
you are and what you have in your backpack
Screening of early root growth characteristics in seedlings of Nordic spring barley
Get PDFIn the Nordic countries, the cultivation of barley (Hordeum vulgare L.) has a long history, and as one of the major cereals in the world, barley is of global importance for food security. The world population is growing, which naturally will increase demands for agricultural outputs. Simultaneously, there is a need for limiting agricultural caused environmental footprints, including excessive fertilizer usage. It is as well projected that climate change will create challenges for global food security, with higher frequencies of extreme climate events with negative impacts on the agricultural sector. In this light, plant breeding for adapted crop varieties is recognized to be important for maintaining stable yields.
Traditionally, breeding efforts have mostly been focusing on improving above-ground plant traits. Although, in later years the advantages of including root architecture traits in breeding programs have been highlighted, e.g. for enhancing resource efficiency, stress tolerance, and plant adaptation to unstable climates. Previous studies have shown that early root growth can correlate with enhanced nutrient uptake and yield formation. In this thesis, a low-tech hydroponic method was used for screening for root dry weight (RootW) and seminal root length (RootL) in seedlings of spring barley. The plant material comprised 259 genotypes of spring barley, from a Nordic PPP–project, including modern lines as well as historic cultivars and landraces, pre-dominantly from the Nordic countries. Moreover, a Genome-Wide Association Study (GWAS) was performed to examine the underlying genetics of the comprised traits.
The root traits were successfully phenotyped using the hydroponic screening method, and in total 23 significant QTLs (quantitative trait loci) associated with the two traits were identified with GWAS. When comparing the result with other association-studies comprising root-traits in spring barley, several of the QTLs in this thesis were located close to QTLs located in those studies. Besides, some candidate genes mentioned in related studies, associated with RootW and RootL, were found in the vicinity of obtained QTLs in this thesis. The statistical analyses, considering correlations between the replicates and the Analysis of Variance (ANOVA), gave support for the results regarding RootL, but the correlations were lower for RootW and a significant effect of the replicates was shown. While comparing differences in early root growth between historic cultivars/landraces and modern breeding lines, a trend was observed where the modern lines generally had higher values for RootW and RootL. Possible reasons for this are discussed.
Overall, the low-tech hydroponic screening method proved to be useful for screening RootL of many genotypes in a short time, which is a trait that previously has been shown to correlate with nitrogen uptake and yield. This by itself could motivate its usefulness. Moreover, the simplicity of the method compared to other more high-tech solutions might make it useful in situations with a restricted budget, when the screening comprises many genotypes, and/or where modern screening systems are out of reach. Although, regarding RootW, the source of the more variable results must be located for the method to be useful. Other traits of early root growth that could have been interesting to assess are discussed
Går det att öka graden av självförsörjning?
Get PDFEtt omtalat uttryck är LRF:s (Lantbrukarnas riksförbund) påstående om att ”varannan tugga i Sverige är importerad”. Det innebär att Sveriges totala självförsörjningsgrad uppgår till 50 procent och landet är därmed beroende av importhandel. Svensk nötköttsproduktion har en stor betydelse för jordbrukets uthållighet. Nötkreatur beskrivs som ”motorn för matproduktion” i Sverige och är därmed en viktig förutsättning för att kunna säkra en bättre självförsörjning av mat i händelse av krig eller annan händelse. Självförsörjningsgraden av nötkött i Sverige har förändrats över tid. Enligt Jordbruksverket har nötkreaturen i Sverige inte varit så få till antalet sedan 1981, då husdjursstatistiken grundades. Sverige har sedan början på 1800-talet varit nettoexportör av spannmål. Självförsörjningsgraden är över 100 procent och landet producerar mer än vad som konsumeras. Under ett år då spannmålsskörden har gett normalstora skördar exporteras hälften till andra länder, vilket gör Sverige till en stor exportör inom spannmål.
Den här uppsatsen syftar till att bidra med förståelse för hur Sveriges självförsörjningsgrad kan ökas med avseende på nötköttsproduktion. För att förstå vilka faktorer som påverkar självförsörjningsgraden behöver läsaren även förstå vilka marknadsvillkor som finns och hur attityder påverkar producenternas beslutsfattande. Producenterna påverkas av marknadsvillkoren, utifrån dessa tar producenterna beslut som sedan påverkar självförsörjningsgraden. De produktioner som jämförs är nötkött och spannmål.
De teoretiska ramverk som uppsatsen grundas på är beslutsteori, teorier om attityder samt SWOT-analys. Uppsatsen är utförd genom kvalitativ forskningsmetod, med en narrativ litteratur-genomgång. Fem respondenter intervjuades och fick besvara de frågor som redogörs i bilaga 1. Deras svar återges i kapitel 4.
Uppsatsens resultat visar att olika marknadsmässiga villkor för produktionerna har skapat de attityder som finns bland människor i samhället. Eftersom det är människor som bestämmer vilka marknadsvillkor som ska finnas, kan det konstateras att producenternas beslutsfattande tydligt kan kopplas ihop med individers attityder. Producenternas beslut angående sina verksamheter är ett resultat av de marknadsvillkor som finns. Producenternas beslut resulterar i sin tur i den självförsörjningsgrad som Sverige har.A famous expression made by LRF (Lantbrukarnas riksförbund) is that “every other bite in Sweden is imported”, alluding to Sweden's self-sufficiency rate amounting to 50 percent. It is because of this that Sweden’s economy and welfare is therefore dependent on import-trading. Swedish beef production is of great importance for the continuance of local agriculture in Sweden. Cattle are described as the "coal of food production" in Sweden and are therefore an important asset for improving self-sufficiency of food. In the event of war or other devastating events, being able to be self-sufficient in terms of food production will be critical for our country. The self-sufficiency rate of beef production in Sweden has changed over time. According to the Swedish Board of Agriculture, the cattle population in Sweden has not been as low as it is right now since 1981, when the livestock statistics were founded. Since the beginning of the 19th century, Sweden has been a net exporter of grain and the self-sufficiency rate for local grain production is over 100 percent. Sweden produces more grain than needed, even when the grain harvest has been meager, half of the total grain production is exported to other countries.
This paper aims to contribute with an understanding of how Sweden’s degree of self-sufficiency can be increased with regard to beef production. To understand the factors that affect the degree of self-sufficiency, the reader also needs to understand what market conditions that do exist and how attitudes affect producers’ decision-making. The producers are affected by the market conditions, based on these the producers make decisions which then affect the degree of self-sufficiency. The productions that are compared are beef and grain.
The theoretical framework on which this thesis is based on is decision theory, theories of attitudes and SWOT analysis. This paper is carried out through a qualitative research method, with a narrative literature review. Five respondents participated in the interview and were asked to answer the questions described in Annex 1. Their answers are reproduced in Chapter 4.
The results of this paper show that different market conditions for the productions have created the attitudes that exist among people in society. Since it is people who decide what market conditions should exist, it can be stated that producers’ decision-making can be clearly linked to individuals’ attitudes. The producers’ decisions regarding their operations are a result of the market conditions that exist. The producers’ decisions in turn result in the degree of self-sufficiency that Sweden has
Evaluation of factors that might affect the grading of heart murmurs in dogs with myxomatous mitral valve disease
Get PDFMyxomatous mitral valve disease (MMVD) is the most common heart disease in dogs. The first
sign of MMVD is usually a heart murmur, which most commonly is detected before clinical signs
of the disease potentially develop. The preclinical period of MMVD is usually long and can be
prolonged with medical treatment. Murmur grading and, primarily, diagnostic imaging techniques
are used to determine if medical treatment is indicated. Many veterinarians use a 6-level scale to
grade heart murmurs. The grades of the 6-level scale are, however, defined differently in various
literature. Several studies have shown a relatively good agreement between murmur grade and
disease severity based on echocardiographic assessment in dogs with MMVD. However, the agreement is not complete.
The aim of this study was to evaluate potential factors, such as dog and mitral regurgitation (MR)
characteristics, that might impact murmur assessment, as well as to evaluate the utility of various
murmur grading scales in a group of dogs with MMVD. Evaluation of the utility of various murmur
grading scales could potentially help optimize existing murmur grading scales. Moreover, knowledge about factors impacting murmur grading could potentially lead to a better understanding of
the association between murmur grades and disease severity (based on echocardiographic assessment).
Client-owned dogs presenting with a heart murmur at the Cardiology Clinic at the University Animal
Hospital at the Swedish University of Agricultural Sciences (SLU) in Uppsala, Sweden, were
prospectively recruited to the study if they, based on echocardiographic findings, had a diagnosis of
MMVD. Information about dog characteristics, data from clinical examination (including murmur
characteristics), and echocardiographic findings were collected. The MMVD severity staging
system (including stages A, B1, B2, C, and D) developed by the American College of Veterinary
Internal Medicine (ACVIM) Specialty of Cardiology Consensus panel was used.
A total of 53 dogs were recruited to the study. A systolic heart murmur could be heard when listening
with the ear close to the chest wall (without a stethoscope) in 44%, 86%, and 100% of dogs in stages
B1, B2, and C-D, respectively. The murmurs remained audible when the stethoscope was lifted
slightly off the chest wall in 11%, 18%, and 63% of dogs in stages B1, B2, and C-D, respectively.
None of the dogs in stage B1 had a precordial thrill, whereas 43% and 78% of dogs in stage B2 and
stages C-D, respectively, had precordial thrills. The murmur grade increased with ACVIM stage.
Most dogs (65% and 83%, respectively) in stages B1 and B2 had an MR jet with a lateral direction,
while most dogs (60%) in stages C-D had an MR jet with a central direction.
In conclusion, whether the murmur can be heard without a stethoscope and specific intensity
descriptions for each grade might be redundant criteria in murmur grading scales. Both the 4-level
and 6-level scales might be useful in dogs with MMVD, but more research is needed to further
evaluate the utility of these and other scales. Furthermore, no firm conclusions about if the factors
investigated impact the agreement between murmur grading and disease severity can be drawn from
the results in this study. Factors such as body condition score, murmur characteristics, and the
direction of the MR jet are still considered potential factors that could impact murmur grading, but
further research with a larger study population is needed
Microbial Carbonisation and its potential for on-farm composting
Get PDFThe search for agronomic solutions to the decline of soil health, open-ended
nutrient cycles and greenhouse gas (GHG) emissions from agriculture, against
the background of impending climate change, were motivations for this thesis.
A composting trial on a Swedish farm was designed to find answers to the
overarching research question of how feasible and climate-friendly on-farm
composting using Microbial Carbonisation (MC) is, compared to conventional
windrow composting (CC). MC can be understood as the biological
transformation of biomass under mesophilic and anoxic conditions, in contrast
to CC, which is an aerobic and partly thermophilic decomposition process.
The investigation of the MC method was approached using natural and
social science methodologies. Field trials were carried out, accompanied by
substrate, soil, emission and pore-gas measurements, as well as records of
machinery use. In addition, interviews were conducted with farmers already
using MC in Germany, to gain a better insight into its practical application and
farmers’ needs.
The results suggest that MC substrates can be richer in nitrogen (N) and
carbon (C) after composting than CC. The machinery requirement of MC was
only one tenth of the more labour-intensive CC process, which is associated
with lower fossil emissions. A novelty of the present research was that nitrous
oxide (N2O) emissions were measured for the first time on a MC compost.
Overall, on a weight basis, MC showed 30 – 40 % lower GHG emissions
during composting, compared to CC. This advantage, however, was offset by
28 – 40 % higher emissions in the field on an area basis. In addition, GHG
balances are highly dependent on the appropriateness of the measurementmethodology,
the period under consideration and the reference unit in which
the emissions are expressed. As CC showed higher N-losses during the
composting process, MC overall emitted 5 – 29 % less GHG per kg N applied
to the field. It was therefore not entirely clear whether MC or CC performed
better in terms of GHG emissions.
As MC can provide N- and C-rich substrates in a cost-efficient way, it
appears promising for the use in regenerative agriculture. The farmers’
interviews supported the results of MC being cost-efficient and practicable for
on-farm composting. Nevertheless, the field application of compost can
substantially increase the GHG balance of what at first sight appears to be a
climate friendly composting process. Future studies need to further address
this issue, as well as the impact of MC substrates on soil health.Die Suche nach ackerbaulichen Lösungen für die Abnahme der
Bodengesundheit, offene Nährstoffkreisläufe sowie Treibhausgasemissionen
(THG) der Landwirtschaft, vor dem Hintergrund des drohenden Klimawandels,
waren Motivation für diese Studie. Ein Kompostierungsversuch auf einem
schwedischen Landwirtschaftsbetrieb sollte Antworten auf die übergeordnete
Forschungsfrage liefern, wie praktikabel und klimafreundlich
landwirtschaftliche Kompostierung mittels Mikrobieller Carbonisierung (MC) im
Vergleich zur konventionellen Kompostierung (CC) ist. MC kann als
biologische Umwandlung von Biomasse unter mesophilen und anoxischen
Bedingungen verstanden werden, im Gegensatz zu CC, welchem ein aerober
und teilweise thermophiler Abbauprozess zugrunde liegt.
Die MC-Methode wurde mithilfe natur- und sozialwissenschaftlicher
Methoden untersucht. Es wurden Feldversuche durchgeführt, begleitet von
Substrat-, Boden-, Emissions- und Porengas-Messungen, sowie
Aufzeichnungen des Maschineneinsatzes. Darüber hinaus wurden Interviews
mit Landwirten geführt, welche MC in Deutschland bereits anwenden, um
einen besseren Einblick in die praktische Anwendung und die Bedürfnisse der
Landwirte zu erhalten.
Die Ergebnisse deuten darauf hin, dass MC-Substrate nach der
Kompostierung reicher an Stickstoff (N) und Kohlenstoff (C) als CC-Substrate
sein können. Der Maschinenbedarf für MC betrug nur ein Zehntel von CC, was
mit geringeren fossilen Emissionen einhergeht. Ein Novum war, dass zum
ersten Mal Lachgas-Emissionen (N2O) von MC gemessen wurden. Insgesamt
waren die THG-Emissionen bei MC während der Kompostierung pro Tonne
Kompost um 30 — 40 % niedriger als bei CC. Dieser Vorteil wurde jedoch
durch 28 – 40 % höhere Emissionen (pro Hektar) auf dem Feld wieder
ausgeglichen. THG-Bilanzen sind in hohem Maße von der Messmethodik,
dem betrachteten Zeitraum und der Bezugseinheit abhängig, in der die
Emissionen ausgedrückt werden. Da CC während der Kompostierung höhere
N-Verluste aufwies, emittierte MC insgesamt 5 – 29 % weniger THG pro auf
dem Feld ausgebrachtem kg N. Es war daher nicht eindeutig, ob MC oder CC
in Bezug auf die THG-Emissionen besser abschnitt.
Wie auch durch die Interviews bestätigt wurde, liefert MC auf
kosteneffiziente Weise N- und C-reiche Substrate und erscheint damit
vielversprechend für den Einsatz in der regenerativen Landwirtschaft. Da die
Ausbringung des Komposts jedoch die THG-Bilanz eines auf den ersten Blick
klimafreundlichen Prozesses deutlich erhöhen kann, sollten künftige Studien
sich mit dieser Problematik sowie mit den Auswirkungen von MC-Substraten
auf die Bodengesundheit näher befassen