Browsing by Subject "forest plantations"

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  • Pienimäki, Arttu (Helsingfors universitet, 2014)
    The most extensive dry forest and woodland formation in sub-Saharan Africa, including Mozambique, is formed by miombo woodlands. Because of their wide distribution, the miombo woodlands carry significance in global carbon cycle. Previous studies have indicated that while the miombo aboveground carbon stocks appear modest in comparison with tropical rainforests, they have a potential to retain high stocks of soil organic carbon. The miombo landscape is nowadays characterized by widespread deforestation and forest degradation, with woodlands being replaced by anthropogenic land uses such as small-scale agriculture and charcoal harvesting. A new land use type spreading in northern Mozambique is formed by industrial forest plantations. The emerging plantations further change the landscape in transition, allegedly affecting the carbon stocks in the process as well. The purpose of this study was to quantify carbon stocks on locally relevant land use classes in Niassa province, northern Mozambique, and evaluate the change of carbon stocks caused by forest plantations. Six major land use classes were identified: dense miombo, open miombo, other woody vegetation, fallow land, eucalypt plantations and pine plantations. A sample plot grid was laid on chosen areas representing each of the classes. Vegetation aboveground carbon stocks (trees, shrubs and herbaceous vegetation) were recorded in the inventory and topsoil (30 cm) was sampled for soil organic carbon content, to be determined in laboratory. Vegetation belowground carbon stocks were calculated based on existing root to shoot ratios. Since plantations were generally juvenile on the study area, their average yield during rotation period was estimated based on growth models to provide comparable results. Forest plantations were found to have carbon stocks of the same order of magnitude as the two miombo land use classes. Open and dense miombo carried mean vegetation aboveground carbon stocks of 27.47 ± 5.77 and 37.65 ± 7.20 Mg ha-1 respectively, and mean total carbon stocks of 67.81 ± 17.09 and 86.81 ± 18.91 Mg ha-1 respectively, which was consistent with pre-existing results. Pine plantations placed in between with a partially modelled total aboveground mean carbon stock of 34.59 Mg ha-1, whereas the corresponding figure for eucalypt plantations was 21.04 Mg ha-1. Dense miombo had the highest mean total carbon stock of all the land use classes, and fallow land the smallest with 42.59 Mg ha-1. Soil organic carbon did not demonstrate statistically significant differences between any of the land use classes. The result was unexpected, and may be explained either by (i) limited time frame since the land use conversions or (ii) soil mineralogical properties buffering carbon stock changes.
  • Wilde, S. A.; Iyer, J. G. (Suomen metsätieteellinen seura, 1963)
  • Juntheikki, Joni (Helsingfors universitet, 2014)
    Purpose of this thesis is to estimate the carbon sequestration potential in eucalyptus plantations in Uruguay. This study also aims to show how beneficial these plantations are for carbon sinks. The aim of this research is calculate total carbon balance in eucalyptus plantations and compare the results to degraded lands. This study is first-of-its-kind study in Uruguay, but not unique globally. The objective was to use a modeling approach to formulate the results. The methodology of this study is based to the dynamic growth model (CO2fix V3.1). Model is developed to calculate and estimate forest carbon fluxes and stocks. In this study the model was utilized for estimating how much carbon is sequestered in eucalyptus plantations and soils. In this thesis the model was used to simulate eucalyptus forest plantations that stem from numerous studies and different data. Ad hoc Excel model was generated to form calculated results from the simulated data. A separate sensitivity analysis is also formulated to reveal a possible different outcome. The framework is based on a stand-level inventory data of forestry plantations provided by the Ministry of Uruguay (MGAP) and companies. Also multiple scientific reports and previous studies were used as guidelines for simulations and results. The forest stand, yield, soil and weather data used for this study are from three different departments. There are over 700 000 hectares of different species of eucalyptus plantations in Uruguay. The theoretical framework was tested computationally with eleven simulations. CO2fix was parameterized for fast-growing eucalyptus species used in different parts of Uruguay. The model gave outputs per hectare and then this result was scaled up to the national level. This study will also estimate how much grassland (Pampa) and former pasture land could sequester carbon. Situation prior to plantation is a baseline scenario and it is compared to the expected carbon sequestration of plantations. The model is also used to calculate the effect of changing rotation length on carbon stocks of forest ecosystem (forest vegetation and soil) and wood products. The results of this study show that currently the 707,674 hectares of eucalyptus plantations in Uruguay have the potential to sequester 65 million tonnes of carbon and reduce 238 million tonnes of CO2. The calculated carbon storage is 38 and simulated 25 million tonnes of C, products are deducted from the equation. During 22 years (1990–2012) the annual carbon sequestration benefit (afforestation-baseline) without products is 1 757 847 Mg C. The results suggest that it is reasonable to establish eucalyptus plantations on degraded, grassland (Pampa) and abandoned pasture land. The implications of the results are that eucalyptus plantations in Uruguay actually enhance carbon sequestration, are carbon sinks and store more carbon than grassland and abandoned pasture land. Plantations have a vast sequestration potential and are important in mitigating of CO2 emission and effects of the climate change. The findings endorse the significance of plantations to increase carbon sinks and this role will broaden in the future. The most relevant findings of this study are that afforestation increases the soil carbon in 10-year rotation plantations by 34% (101.1>75.6) and in 12-year rotation 38% (104.4>75.6 Mg Cha-1) in a 60-year simulation. The net (afforestation-baseline) average carbon stock benefit in the soil is 25.5 Mg C ha?1 in a 60-year simulation. The (CO2Fix) model indicate that the total average carbon sequestration for eucalyptus plantations is 92.3 Mg Cha?1. The average total carbon storage ranges from 25.8–138.5 Mg Cha?1 during a 60-year simulation. The simulations show that the net annual carbon storage in the living biomass is 29.1, 25.5 (soil) and 37.6 Mg C (products) on the average scenario. There is some fluctuation in the sequestration results in other 10 simulations. Previous studies have showed that the average carbon stock for eucalyptus plantations varies from 30–60 Mg C ha-1, when soil and products are deducted. The capacity of forest ecosystems to sequester carbon in the long run could be even more strengthened if a rotation length increases. Extending rotation from 10 to 12 years increased the average soil carbon stock from 25.5 to 28.8 Mg C (by 13%) in 60 year simulation. The results also indicate that mean annual precipitation (MAP) alters the carbon sinks of the forest ecosystem. There are some limitations in this study and they are clearly explained and analyzed. Hence, most of the results are estimations. Ministry and companies need to prolong planting of trees and even intensify annual programs in order to achieve carbon sequestration targets. Further research is needed to get an estimate of the total forest ecosystem carbon storages and fluxes.
  • Korhonen, Jaana (Helsingfors universitet, 2013)
    Direct investments are considered the main source of economic growth and are desirable for countries. Factors driving the geographical distribution of direct investments are unknown. Many forest investments are directed to plantations, which have expanded rapidly during the past two decades. The global forestry scheme is changing; until 1990, developed countries accounted for almost all investments. Since then, developing countries have started to employ them at an accelerating rate. The major changes in a world economy are likely to drive this trend in the future. To assess factors contributing to investment in forest plantation, we drew from methods used by the Inter-American Development Bank (IADB), which developed a forest attractiveness index (IAIF) to ?measure the business climate to sustainable forest business?. In this research, several multiple linear regression models were developed to examine the effects of different variables. As well, different macro-economic, institutional, and forest-sector factors were considered the main components that drive forest plantation development. Factors attracting direct investment in forest plantations are different on a global scale, in developed and developing countries. Therefore, some general trends can be identified: Macro-economic factors are important. Foreign direct investment inflows and area of planted forests are positively correlated, indicating that the investment behavior of forestry investors is not significantly different from other investors‘. Other significant factors are GDP and the exchange rate. GDP was positively correlated with the area of planted forests. Weak currency is desirable in OECD countries, and a strong currency is favorable for plantation investments in non-OECD countries. Institutional factors were not significant, which suggests investments occur despite the country challenges. The human development index was the most significant factor in this category. The human development index had a negative effect on the area of planted forests. The more developed a country, the fewer plantations. The forest-sector factors were the most important factors that determine plantation investment attractiveness. Production capacity and productivity were globally significant. Productivity was not significant in non-OECD countries, which may have equally beneficial circumstances for tree growth. Macro-economic factors are important especially in these countries. The results suggest macro-economic and forestry factors are key determinants of investment attractiveness in forestry. Macro-economic factors cannot be affected by investors. Forestry-factors can be affected by country level decision making. Investors can choose between countries, and sometimes affect these factors. These results may be useful to firms considering foreign direct investment and to policy makers in potential destination countries.
  • Väisänen, Janne (Helsingin yliopisto, 2019)
    Reducing global carbon dioxide emissions is one of the main targets in the fight against climate change. Forests are important carbon pools and the arid regions of the world hold a great carbon sequestration potential. Dryland afforestation could play a considerable part in climate change mitigation. The aim of this study is to understand plantation forestry and the costs of afforestation work in arid and semi-arid regions. The main objective of the study is to estimate the establishment costs of 5.000-hectare irrigated forest plantation in Morocco, planned by the Finnish energy company St1. The plantation establishment costs are consisted of labor factors, such as preparing and mapping the cultivated area, fencing, seedling production, tillage, planting and aftercare, and other maintenance operation. The irrigation cost consist of developing the irrigation system, operation and maintenance costs and the price of desalinated seawater used in the plantation. The research timeframe was set to be from 0 to 5 years, assuming that this period covers the major cost factors of the plantation establishment. According to the results, the total establishment cost of the St1’s 5.000-hectare forest plantation, planned in Morocco, is estimated to be approximately EUR39 million and the cost per hectare around EUR7800. The total cost of cultivation is estimated to be about EUR18 million and the total cost of irrigation in the first four years are around EUR21 million.
  • Binkley, C.S.; Apps, M.J.; Dixon, R.K.; Kauppi, P.E.; Nilsson, L.-O. (CRC Press, 1997)
  • Bleyer, Maja (Helsingfors universitet, 2015)
    The low population density and consequent high land availability in Niassa, Mozambique have attracted foreign private forest investments. Since 2005 forest companies have acquired the right to establish forest plantations in the area, which naturally affects the livelihoods in communities located close by. This study aimed to analyse the impact of forest plantations on the livelihood and wealth of local communities. The main objectives were the evaluation of impacts on natural resources, livelihood strategies and differences in the experienced impacts between different wealth groups. With these objectives, household interviews, focus group meetings and key informant interviews were held in five different villages in the province of Niassa. With principal component analysis (PCA) weights for valuable assets possessed by households were created and summed up to a factor score. On the basis of these scores the households were divided into three wealth groups, which were used to analyse differences in the perception of different groups of households. The main analysis of the perception of impacts on the natural resources, livelihood strategies and overall livelihood was carried out with binomial and multinomial logistic regression models. The results showed that while the natural capitals were impacted negatively by the establishment of forest plantations, households benefited from more diversified livelihood strategies. Furthermore, it was discovered that the wealth of a household does not have a major impact on the perception of impacts of a household. Instead relocation of farm plots and formal employment have been identified as determining factors. The study showed that the perception of the impacts differs greatly between the villages due to different initial resource endowment and different forest companies. Throughout the study it became evident that the weak implementation of land use rights is an underlying cause for many conflicts between companies and local communities.