Browsing by Subject "carbon sequestration"

The objective of the thesis is to review and characterize (i) typical agroforestry systems in the temperate zone, (ii) levels of soil organic carbon (SOC) in agroforestry and control plots, and (iii) identify the conditions under which agroforestry farming is most likely to enhance SOC. A meta-analysis was conducted to investigate the impact of agroforestry farming systems on SOC stocks at soil depths of 0 – 20, 0 – 40 and 0 – 100 cm. Data was collected from 15 published studies and all sites are located in temperate climates. Studies had to report at least measurements on SOC concentration or stock for an agroforestry plot and a control plot (arable land, grassland, forest). Investigated treatment variables were soil depth, agroforestry system type, soil type, tree species and age. The results have shown significantly higher SOC stocks under agroforestry in comparison to controls in all three soil depth datasets. The largest amount of SOC in agroforestry was found in the first 20 cm of topsoil and at a soil depth of 60 – 100 cm. There were no significant differences found between alley cropping, silvopasture and shelterbelt systems. The most popular tree species in temperate agroforestry were Populus spp., M.domestica, Juglans regia and Picea. But no significant differences in C sequestration could be observed between tree species across all datasets. The assumption that systems with older trees have higher stocks of SOC could not be confirmed. Most common soil types of temperate agroforestry systems were Luvisol, Fluvisol and Chernozem. The meta-analysis did not verify results of other studies, which have shown that clay contents in the soil promote C sequestration. The wide variability and diversity of agroforestry systems has shown to be problematic in conducting a meta-analysis, indicated by a high heterogeneity. Furthermore, different types of study designs, lack of standardized sampling procedures and explanatory variables may have influenced the results. However, the study showed that agroforestry can be a promising carbon dioxide (CO2) mitigation option, also for the temperate climate zone.

Since the term blue carbon was first coined in 2009, the interest in the carbon stocks and annual carbon sequestration of mangrove forests, salt marshes and seagrass meadows has increased noticeably. However, in the past couple of years, the carbon capabilities of kelp forests have also started to garner more attention, leading to multiple published studies arguing for their inclusion as a blue carbon ecosystem. However, so far, few studies have actually compared the amount of carbon stored and sequestered by kelp forests to the three traditional blue carbon ecosystems. Thus, the aim of this thesis was to estimate and compare the amount of carbon currently stored and annually sequestered by the different blue carbon ecosystems. Furthermore, the effects and costs of blue carbon ecosystem degradation were also estimated. Based on the results of a thorough literature review regarding the global distribution and degradation rates of the ecosystems as well as the amount of carbon sequestered and stored per unit area, the total amount of carbon stored in blue carbon ecosystems is estimated to be between 5 and 25 Pg, with mangrove forests storing roughly half of that. Yet, whilst kelp forests are estimated to have a far larger global distribution than all of the other blue carbon ecosystems combined, they only store around 0.1–1.4 Pg of carbon, since all of the carbon is stored in their biomass, unlike the other blue carbon ecosystems, in which the vast majority of carbon is located in the soils. However, the total amount of carbon sequestered annually by all blue carbon ecosystems is estimated to be between 40 and 331 Tg, out of which 8–231 Tg is sequestered by kelp forests. Yet, due to the degradation of the ecosystems during 2022, a combined 30–294 Tg of the previously stored carbon is estimated to be released into the atmosphere, whilst the amount sequestered during the year is reduced by roughly 0.4–6 Tg. Out of the carbon released, the majority is from the carbon stocks of seagrass meadows, whilst the carbon sequestration of kelp forests is reduced the most. The total combined cost of the degradation equals €9–174 billion, when the costs of the previously stored carbon released is combined with the NPV of the reduced carbon sequestration. Out of this, the total cost for kelp forests is estimated at €1–59 billion. However, whilst the number of studies published on blue carbon has increased, the data available regarding the ecosystems is still limited. As such, there are considerable uncertainties regarding the values presented and the results of the thesis should thus be considered rough estimates. That being said, the results still underline the importance of blue carbon ecosystems as carbon sinks as well as the considerable costs caused by environmental degradation. Furthermore, the thesis provides further support for the notion that kelp forests should indeed be considered a blue carbon ecosystem.

Climate change and the biodiversity loss have created a need to change forest management in commercial forests. Carbon sequestration, climate change adaptation, and biodiversity conservation can be promoted in commercial forests through various measures, and this thesis examines what factors affect non-industrial private forest (NIPF) owners’ willingness to adopt such forest management practices. Additionally, the aim was to examine whether these factors vary among different measures. A systematic literature review was conducted to summarize previous research on the subject and to serve as reference for an empirical analysis. In the empirical part of the study, survey data of 405 Finnish NIPF owners was utilized to establish binary logistic regression models for forest owners’ willingness to adopt 13 distinct forest management practices. In the empirical analysis statistically significant factors varied among assessed forest management practices, although some patterns were recognized. The most striking consistencies were found concerning older forest owners reluctance towards deadwood in general, and positive effect of environmental motivation in willingness to adopt variety of measures, as long as they do not conflict with biodiversity. Overall, the results imply that the diversity of NIPF owners concerns also their stances on various forest management practices, and they are not indifferent in terms of what forest management practices they are willing to adopt. Thus, when designing and implementing policies and advisory services aiming to promote carbon sequestration, climate change adaptation, or biodiversity protection in commercial forests, policy makers should take into account forest owners’ heterogenous preferences regarding different forest management practices.

The Atlantic forest on the Eastern coast of Brazil is one of the world’s most endangered biotopes. Less than 12 % of the original forest remains due to agricultural and pasture expansion. In addition, many Atlantic forest restoration projects in the past have failed, largely because of inadequate silvicultural practices. Meanwhile, the growth rates of Eucalyptus and pine plantations have been increased 3 to 4 fold in Brazil over the last four decades by utilizing intensive silvicultural methods such as site preparation, fertilization, and weed control which in turn increases resource supply (nutrient, water and light). This study determines the effects of these same intensive silvicultural methods on Atlantic forest restoration regarding initial growth and carbon sequestering. Two parallel research sites were established in 2004 on latitudes 11°S and 23°S on the Eastern coast of Brazil to determine the effects of intensive silviculture, planting density and species composition on the development of 20 native tree species. This research focused on the Northern site (200 km North of Salvador, Bahia State) which has a typical tropical climate and soil type. The project has a 23 factorial design totalling 8 treatments, with the following factors: i) intensive and traditional treatments; ii) initial planting densities (3333 trees ha-1 and 1667 trees ha-1); and iii) species composition proportion (50:50 and 67:33 ratio of pioneer vs. late successional species). After 8 years from planting, survival and development of each species, aboveground biomass and leaf area index (LAI) were determined for all the treatments to compare the effects of the different factors. In summary, the main findings of this study are: 1) The more intensive management methods improved survival and the initial growth of tree species 2) Lower stand density (1667 trees ha-1) had the best response to the intensive management for LAI, stemwood production, and above ground carbon sequestration 3) Out of 20 species, 19 had significantly higher growth with intensive management, indicating that both pioneer and late successional species are constrained by the original site conditions. 4) Intensive management was essential, especially for non-pioneer species. 5) Under low intensity silviculture, the 67:33 ratio pioneers vs. non-pioneers with higher planting density (3333 trees ha-1) was the best option to obtain the highest stemwood volumes 8 years from planting, while the 50:50 ratio pioneers vs. non-pioneers with lower planting density (1667 tree ha-1) could be recommended under intensive silviculture. Conclusion: Intensive management methods have the potential to increase early restoration success by increasing biodiversity through enchancing survival and growth of non-pioneer species and accelerating the canopy closure. Intensive management methods increased the above ground carbon sequestered in 8 years, remarkably, up to 3-fold compared to traditional management, making it an attractive management option for carbon offsets.

Maaperästä vapautuu hiiltä ilmakehään maatalouden vaikutuksista. Nautojen laiduntaminen voi sitoa hiiltä takaisin maaperään. Laidunnuksen hiilensidonnan määrä riippuu pitkälti laidunnusstrategiasta, eli siitä kuinka kauan ja kuinka iso lauma kerrallaan laiduntaa tiettyä aluetta ja kuinka kauan laidun saa levätä ennen eläinten palaamista takaisin. Suomessa tavanomaisin laidunnusstrategia on intensiivinen, kiertävä lohkosyöttö, jossa laidunlohkolle tulee tyypillisesti viisi syöttökertaa kesän aikana ja syöttökertojen välinen lepoaika on kahdesta viikosta kuukauteen. Tutkimuksen kohteena olevassa, uudessa laidunnusstrategiassa MOB-laidunnuksessa nurmen massa on suuri ja lepoaika on pitkä, tästä syystä syöttökertoja tulee kesän aikana vain kolme. Tämän maisterintutkielman tarkoituksena oli selvittää, sopiiko MOB-laidunnus suomalaisiin olosuhteisiin ja miten se vaikuttaa laidunalan tarpeeseen ja hiilisyötteeseen nuorkarjalla. Hypoteesina oli, että vaikka MOB-laidunnus lisää laidunalan tarvetta, sekä heikentää laidunnurmen ruokinnallista laatua intensiiviseen lohkosyöttöön verrattuna, se toimii silti hyvin nuorkarjan laidunnuksessa. Lisäksi MOB-laidunnuksen odotettiin parantavan hiilisyötettä peltoon jäävän suuremman kasvustomassan ansiosta. Koe suoritettiin Luonnonvarakeskuksen tutkimusasemalla Maaningalla 29.05.2021-25.08.2021. Koe sisälsi kolme laidunkiertoa tavanomaisilla laidunnusruuduilla (4 ruutua, n. 570 m^2/ruutu) ja kaksi laidunkiertoa MOB-laidunnusruuduilla (4 ruutua, n. 320 m^2/ruutu). 16 hiehoa oli jaettu neljään ryhmään ja ne laidunsivat ruutuja kahdesta neljään päivään, jonka jälkeen hiehot siirrettiin pois ja laidunruudut saivat levätä. Tässä kokeessa keskimääräinen lepoaika tavanomaisessa laidunnuksessa oli intensiiviselle laidunkierrolle ominainen 25 vrk ja MOB-laidunnuksessa matalan intensiteetin laidunkierron mukainen 37 vrk. Lepoajalla hiehot laidunsivat yhtenä ryhmänä ja silloin niillä oli tarjolla kivennäistä, jota ruutusyöttöjen aikaan ei tarjottu. Koealan nurmi oli perustettu seoksella, jossa siemensuhteet olivat 60 % timotei (Phleum pratense L.), 20 % nurminata (Festuca pratensis Huds.) ja 20 % puna-apila (Trifolium pratense L.). Laidunruuduilta otettiin kasvustonäytteet ennen ja jälkeen jokaista laidunkiertoa. Näytteiden perusteella analysoitiin laidunnurmen rehuarvo sekä arvioitiin hiehojen syömän laidunrehun määrä. Ruuduilta mitattiin laidunkauden päättyessä myös multakorjattu sänkimassa, josta pystyttiin arvioimaan maan pintaan hiilisyötteeksi jäänyt nurmimassa. Ensimmäisen syöttökerran alkaessa tavanomaisten ruutujen alkumassa oli 2755 ja MOB-ruutujen 5344 kg ka/ha. Laidunnusstrategia vaikutti laidunnurmen koostumukseen, tarvittavan laidunalan ja hiilisyötteenä toimivan sänkimassan määrään. MOB-laitumien nurmen sulavuus oli heikompaa kuin tavanomaisilla laitumilla, mutta laidunrehun sulavuus ja kemiallinen koostumus riitti täyttämään nuorkarjan energian ja ohutsuolesta imeytyvän valkuaisen (OIV) tarpeet. Kuiva-aineena mitattuna MOB-laidunnuksen nurmen hehtaarikohtainen sato oli 11 % pienempi verrattuna tavanomaiseen laidunnukseen. Syönnissä (kg ka/pv/eläin) ei ollut ensimmäisellä syöttökerralla eroa laidunnusstrategioiden välillä (P = 0.67). Toisella syöttökerralla MOB-laidunnuksessa syönti oli numeroarvoisesti suurempi kuin tavanomaisessa laidunnuksessa (5.3 vs. 7.8, P = 0.12). MOB-laidunnuksen jälkeen peltoon jäi nurmimassaa noin 2000 kg ka/ha enemmän kuin tavanomaisen laidunnuksen jälkeen. MOB-laidunnuksessa kasvu ei kärsinyt kuumuudesta ja kuivuudesta tavanomaisen laidunnuksen tapaan. Negatiivisena puolena verratessa tavanomaiseen laidunnukseen MOB-laidunnus lisäsi laskennallisesti 38 % laidunalan tarvetta, joka voi muodostua ongelmaksi laidunalan riittävyyden kannalta ja myös taloudellisesti. Hiilensidonnan näkökulmasta MOB-laidunnus on parempi vaihtoehto tavanomaiseen laidunnukseen verrattaessa, sillä MOB-laidunnuksessa ylilaidunnusta ei päässyt tapahtumaan ja pilalle tallattua nurmea oli selvästi tavanomaista laidunnusta vähemmän. Myös sänkimassaa jäi maahan huomattavasti enemmän hiilisyötteen lähteeksi kuin tavanomaisen laidunnuksen päätteeksi. Tässä tutkimuksessa MOB-laidunnus todettiin toimivaksi vaihtoehdoksi nuorkarjan laitumena.

This thesis studies market demand and supply in the voluntary forest carbon markets. The first section focuses on demand and provides an overview about the market mechanisms, buyer’s reasons to buy credits, and current demand in the markets. Supply will be studied with supply-chain approach. Supply-chain is a system moving a product or service from supplier to customer. The supply-chain section is divided into three parts. The first part finds out whether or not forests have the ability to sequester carbon and what kind of forest projects there has been. It also introduces the processes in which forest carbon credits are issued. The second part focuses on certification and verification schemes. Third part presents market places and the actors involved in carbon credit trading. Carbon markets will be evaluated on foreign and domestic basis. The aim of this thesis is to find out how well the voluntary carbon markets meet the conditions of perfect competition. The theory is based on the theory of competitive market structure and the price mechanism, where demand equals supply at the equilibrium price and quantity. The equilibrium should be found automatically within a perfectly competitive market when buyers and sellers interact. The empirical part of the study examines carbon credit issuance, project processes, certification and markets. The research questions are: 1. Do markets have infinite buyers and sellers? 2. Are products homogenous? 3. Do consumers and producers have perfect knowledge of price, utility, quality and production methods? 4. Is it easy to enter or exit the markets? The thesis is based on literature. Standards, marketplaces, and projects that were selected to the study were chosen according to the popularity based on market volume or forest-related characters. The research approach is qualitative. The collected data was analysed using content analysis. Economics and market theory form the theoretical basis of the analysis. Classification of the data is based on the theoretical framework. According to the theories a loose framework was formed to allow data reduction. Framework divides demand and supply-chain into separate parts. Research question number one is examined using a demand section. Research questions numbers 2-4 are examined using supply-chain sections. The study resulted in a conclusion that voluntary forest markets do not meet the conditions of perfect competition. Voluntary forest carbon markets are not perfectly competitive. Instead markets are uncompetitive where commodities are heterogeneous. There is only limited amount of forest projects and forestry based credits. Unit price is set to match the cost, in which case it is not determined by the market. Price-setting is possible because it is possible to differentiate projects. Imperfect competition in the market remains for mobility obstacles between markets have been set. Credit certified under certain standard, are not generally acceptable to another standard. The study results support the findings of studies conducted in the past.

Forests have acted as a substantial Carbon sink during the last decades. In Finland, forests currently sequester about half of the total anthropogenic CO2 emissions. In order to mitigate climate change, most recent policies, both on the European and the Finnish level, are focussing on increasing forest utilisation, and use forest biomass to substitute fossil resources for material or energy production purposes. However, as increasing harvests commonly reduce the growth potential of forests, their function as a carbon sink could be reduced. This reduction of the forest carbon sink might offset the reduction in emissions gained by substitution. The aim of this study is to analyse how different levels of forest utilisation, i.e. harvest levels, and climate change affect the carbon sink function of Finnish forests at a national level during the period of 2015–2100. In order to quantify these effects in detail, the semi-empirical, climate- and management-sensitive forest growth simulator FORMIT-M is employed to estimate carbon stocks and fluxes in living biomass. The carbon stocks and balances of soils are calculated by applying the Yasso15 soil model to litter input as modelled by FORMIT-M. The carbon balance of harvested wood products is estimated by applying species- and assortment-specific decay functions to harvested timber assortments derived from dimensions. Four harvest scenarios were applied, covering total annual harvest levels between 40 and 87 million m3 a-1, i.e. both reduced and increased levels compared to current levels. The simulations were run for three climate scenarios: current climate (1981-2010 means), and RCP2.6 and RCP8.5 scenarios, the latter two based on predictions of the general circulation model CanESM2. The general findings of the simulations largely confirm earlier research, indicating that higher harvest levels decrease the total C sink. This was true across all climate scenarios examined; in general, the total C sink function of forests was predicted to increase under climate change conditions, with higher C sinks under RCP8.5 than RCP2.6. Under climate change, the relative effect of increasing harvests is reduced, but management in the form of harvest levels remains a more influential factor than climate change. In addition, the reduction in C sink function per unit of additionally harvested C is larger at higher harvest levels, especially under current climate. In the highest harvest scenario, managed forests acted as C sources in the beginning of the modelling period, and the total Finnish forest areas remain net C sinks only due to net C sequestration in preservation areas during this period. The simulations of this study therefore suggest that, from a climate change mitigation perspective, a reduction of harvests is more beneficial than increasing harvests. This is true even when avoided greenhouse gas emissions by replacing fossil resources with forest biomass are considered in the form of a rough estimation of substitution effects. In general, both the absolute magnitude of the C sink and the differences between harvest scenarios are likely to be overestimated in this study, as neither the reduction in growth potential nor the potential reduction of C stocks due to natural disturbances were considered; in addition, potential limiting factors such as nutrient deficiency did not restrict the fertilisation effect of elevated atmospheric CO2 levels. The results include large uncertainties, both regarding the effect and extend of climate change and the potential accumulation of misrepresentations within the growth modelling; hence, the reliability can be expected to decrease during the modelling period. Future applications of the FORMIT-M simulator in Finland should consider the effects of natural disturbances as well as limitations to the substantially improving growing conditions due to climatic conditions and elevated atmospheric CO2 levels; in addition, an optimisation procedure for the distribution of harvests would be beneficial.

Carbon neutral agriculture plays a key role in climate change mitigation. However, Finnish farmers are struggling with the impacts of climate change and the profitability crisis. This study aims at providing market insight on potential sources of income for Finnish farmers in carbon neutral agriculture by 2030. However, this thesis does not focus on the question whether carbon neutral agriculture is achievable. The role of policy instruments is also investigated to determine whether they facilitate or prevent changes. The thesis is commissioned by Envitecpolis Oy. Six experts from the agriculture field were interviewed and the data were analysed with theory-driven content analysis. The analysis is based on the future signals sense-making framework (FSSF) that focuses on the weak signals, drivers and trends found in the data. Each theme includes two categories; the nonlinear and linear paths of change. In addition, policy instruments were divided into promoters and disrupters of change. The relevant weak signals identified are innovations, the formation of premium markets, the adoption of paludiculture, novel and existing market mechanisms for carbon neutral practices, the substitution of materials and energy in production, digitalization, the increasing requirements for producers by food industry and by consumers and lastly, strengthened cooperation between actors in agriculture. The drivers of change, such as climate change, knowledge and advances in technology, significantly influence the adoption of these weak signals. However, various trends function as blockers of change whilst some trends are inevitable large change processes. In light of the results, weak signals of potential sources of income are not likely to become mainstream by 2030. However, existing or emerging issues may play a key role in providing additional income for farmers. National agriculture policy and the EU Common Agriculture Policy (CAP) are complex schemes that are gradually emphasizing climate issues. However, these policies fail to incentivize farmers to adopt practices for carbon neutral agriculture. Recommendations for future research include the cost-effectiveness of climate change mitigation measures and a follow-up on the sources of income for farmers in 2030.

Forests are vital for biodiversity and climate change mitigation through carbon storage and sequestration. In Finland, forests are the most important renewable natural resource and forestry is significant for the national economy. In addition, forests are the largest carbon sinks of the land use, land-use change and forestry (LULUCF) sector and provide remarkable amount of biodiversity. The Finnish non-industrial private forest (NIPF) owners have significant potential to supply ecosystem services and have substantial opportunities regarding the forests, as 60% of the total area of forest land is privately owned. The NIPF owners may enhance the state of biodiversity and carbon sequestration by participating in the forest conservation programs. The regulations and inclusion of the LULUCF sector in the climate targets of the European Union (EU) and a 30% conservation target of land in the EU Biodiversity Directive are intensifying the pressure on further development of conservation programs. Hence, it is important to understand the behavior of the NIPF owners to motivate the program participation. The aim of the thesis is to get insight into the Finnish NIPF owners’ participation behavior in permanent forest conservation programs by using the choice experiment (CE) method. A novel conservation program is being planned in Finland and this survey processes it for the NIPF owners by using a survey questionnaire. The survey questionnaire was targeted to 5,010 NIPF owners and the overall response rate was 11.7%. The study provides analysis on specific non-participant group of protesters, attribute preferences of the conservation program as well as estimates of the willingness to accept (WTA) compensation for program participation. The forest conservation program is described with four attributes being the payment for biodiversity; payment for carbon sequestration; conduction of non-timber businesses and eligibility of the forest area. The sources behind preference heterogeneity regarding the conduction of non-timber businesses and eligibility of the forest area are examined using interactions in the econometric model. The results reveal that a significant share (77%) of serial non-participants are identified as protesters and should be excluded from the WTA estimates. Several socio-economic and attitudinal characteristics were found to statistically significantly influence on protest behavior. The probability to protest increases with e.g. older age, pensioners, female gender and renters for hunting club. Additionally, the protest behavior depends on a number of stated attitudinal statements. Using a binary logit model, the model estimates show that the WTA for program participation is considerably higher when protesters are included, being 16,032 €/ha and respectively 5,641 €/ha, when protesters are excluded. The results regarding the preferences reveal attitudinal and socio-economic aspects affecting statistically significantly on the program attribute of the eligibility of forest area. According to the analyses, the possibility to conduct non-timber businesses is rather irrelevant for the respondents. In addition, there are a few attitudinal factors that influence the preferences of the conduction of non-timber businesses which are statistically significant. However, none of the socio-economic factors regarding the preferences of the attribute are statistically significant. To our knowledge, this is the first study that aims to explain the sources behind protest behaviour as well as to investigate the conduction of non-timber businesses, in the context of permanent forest conservation program. The results provide novel information about protesters and preferences of program attributes of forest management requirements and conduction of non-timber businesses. The results may be useful for the development and targeting of voluntary forest policies and incentives as well as for the business development of organizations that provide services for the NIPF owners. Further, the results help recognizing protesters more easily and reducing protest behavior. To conclude, further studies on the objectives of protests in the context of permanent forest conservation program could be valuable. In addition, further examination on individual attribute level WTAs, could be useful to reveal detailed information of the program attributes of conduction of non-timber businesses and required management activities.