Browsing by Subject "ecosystem services"
Now showing items 1-7 of 7
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(2023)Ecosystem accounting is a new framework for integrating the value of nature into decision-making. Previous measures of natural capital accounting have not been able to achieve policy relevancy and have only limited use cases. It is important to look into the usability of ecosystem accounting, to ensure that it is implemented in a way that supports decision-making. The goal of my research is to provide a categorization of barriers and enablers of use, as well as provide some insight into how to make ecosystem accounting usable for decision-making. There is only limited literature on ecosystem accounting, so I conducted a scoping literature review on barriers and enablers of use of natural capital accounting to look into the issues and opportunities in making ecosystem accounting usable. I complemented this literature review with interviews of ecosystem accounting experts from Norway and Germany. Both countries have started the implementation journey and thus provide a view into the active development phase. My main results are the categorization of barriers and enablers of use of ecosystem accounting, as well as main messages for creating usable accounts. I categorized the barriers and enablers into 12 categories under three themes of political, structural and relevancy related barriers and enablers. The categories can be used when planning implementation to identify potential issues and to plan accounts to be as usable as possible. I have three main messages for compiling usable ecosystem accounts. First, sufficient resources are essential in gathering comprehensive accounts. Second, compiling the accounts rely on cooperation of multiple institutions, thus there is a need to agree on forms of coordination. Third, the categories of barriers and enablers are interconnected, and thus there are positive feedback loops that can support making ecosystem accounts usable for policymaking.
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(2023)Climate change severely threatens ecosystem services and human well-being: vegetation and soils underneath it can be particularly vulnerable to climate warming. Soils hold the largest carbon stock in terrestrial ecosystems, and urban park soils, especially in cool climates, can hold remarkable carbon stocks and may be able to offset some atmospheric CO2 emissions. Land use changes, such as urbanization, influence soil organic carbon formation and soil carbon storages. In this study, I was interested whether three vegetation types (deciduous trees, conifers and lawn) differ in their capacity to store C in their rhizosphere, and whether this is affected by park size. I measured the proportion of tree canopy layer in class A park areas of the city of Helsinki, to estimate soil C storages of these areas and to examine C density (kg C m-2). Proportions of tree canopy layers in different park size groups were measured using QGIS and ortographs. Soil C storages were calculated using existing soil C data and average proportions of conifer and deciduous trees in parks of the city of Helsinki. Park size had a significant effect on proportion of the tree canopy coverage: canopy cover decreases with an increase in park size. Especially large parks are dominated by lawn. The average soil C densities in small, medium and large parks were 23.98 kg C m-2, 23.47 kg C m-2 and 23.15 kg C m-2, respectively. However, the overall proportion of conifer canopy in parks of the city of Helsinki is rather small, resulting in small differences in C densities between different park size categories, despite significant differences in tree canopy coverage between the three size groups. Most of the stored soil C in parks of the city of Helsinki are under lawn, even though it is the least efficient of the three studied vegetation types (deciduous trees, conifers, lawn) in soil C sequestration. Within a park size category and at park level, large parks store the highest amount of carbon per park. Even so, at the city level, the total amount of carbon is highest in the small parks due to their high number. Conifer trees associate with improved C sequestration to soils compared to deciduous trees and lawn. Increasing the amount of conifer trees in urban parks thus likely increase the important C storages of these soils. Results of this study highlight the importance of the contribution of urban parks and especially conifer trees in carbon sequestration. Future research related to urban soil C sequestration and the effects of vegetation type and climatic conditions is needed to better understand soil C accumulation and how the C sequestration of urban park soils could be enhanced.
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(2021)Pollinator abundance and diversity are declining at an alarming rate around the world, which poses a threat to ecosystem stability and human wellbeing. There are signs that growing pollination deficits are limiting agricultural yields in Finland and globally. More information is urgently needed on how changes in pollinator communities affect crop yields and how adequate pollination services could be achieved across a range of crops and locations. This study explores the effects of pollinator abundance and diversity on caraway (Carum carvi L.) pollination and yield. Caraway is partly wind-pollinated, but insect pollination has been shown to increase its yield. Flower visits of pollinating insects were monitored on 30 caraway fields in southern Finland in summer 2019. Yield samples were collected from open-pollinated plants and from control plants excluded from pollinators. Pollinator exclusion reduced caraway fruit set by 13.2% and seed yield by 39.6%. Fruit set, 100-seed weight and seed yield increased with increasing flower visitation. Pollinator species richness and Shannon index had no significant effect on the yield components, but evenness of the pollinator community had a negative effect on seed yield and the numbers of umbels and umbellets in the caraway plants. The most abundant pollinators visiting caraway were syrphid flies, non-syrphid Diptera and honeybees. Visits by syrphid flies and honeybees increased seed yield, while visits by non-syrphid Diptera, solitary bees and Lepidoptera had no significant effect on the yield components. Flower visits by beetles reduced 100-seed weight. The results show that syrphid flies provide an important pollinator service for caraway cultivation. It would be beneficial to study which syrphid fly species are the most effective pollinators for caraway and how to manage fields and farmland landscapes to increase their numbers. Relying only on managed honeybees to enhance caraway pollination may not be advisable due to their potential negative effects on wild pollinators. While increased pollinator diversity did not improve caraway pollination or yield in this one-season study, it may be important for the stability of pollinator services in long term.
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(2022)Biodiversity loss and ecosystem service degradation and the related economic costs are increasingly recognized as sources of financial risks. The risks are arising through physical and transition sources of risks caused by dependencies and impacts upon biodiversity and ecosystem services. Therefore, it has become increasingly important for both individual financial institutions as well as central banks and financial supervisors to better understand and manage these risks. However, biodiversity loss is associated with unique complexity and uncertainty, making it a challenging task. The purpose of this thesis was to study the linkages between biodiversity loss and financial stability in Finland. This was done by assessing the financial exposure of Finnish credit institutions to sectors dependent on ecosystem services for their production processes. A quantitative analysis was conducted in order to combine loan data obtained from the Bank of Finland and ecosystem service data obtained from the ENCORE database. The results showed that 23% of loans provided by Finnish credit institutions are exposed to high or very high biodiversity-related financial risks. The sectors associated with most value at risks were real estate and agriculture, forestry and fishing sectors. Disruptions of ecosystem services providing surface water and climate regulation were posing the highest financial risks. The findings represent a first step towards assessing the exposure of the Finnish financial system to biodiversity-related financial risks. The results and previous literature indicate that physical biodiversity-related financial risk exposures are significant for individual financial institutions and for the whole financial system, despite the prevailing methodological challenges and gaps in knowledge. In order to complete a comprehensive biodiversity-related financial risk assessment, further research is needed.
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(2022)The intensification of agriculture is one of the main drivers of biodiversity loss worldwide. One of the intensification shifts has occurred from cattle grazing on biodiversity-rich semi-natural grasslands to ceased grazing or grazing on cultivated species-poor grasslands. While the effect of different grazing pressure on biodiversity in semi-natural grasslands has been studied extensively, little is known of how current grazing regimes on cultivated grasslands affect biodiversity and ecosystem services in different farming systems. Here, we investigated how arthropod abundance and potential ecosystem services are related to varying grazing pressure on cultivated grasslands at conventional and organic farms with meat or dairy production. We sampled aerial arthropods with sticky tape traps in four land-use types within the farms. Relative arthropod abundance was derived from the tapes using an imagery analysis, and the numbers of pollinators and predators from 4 taxonomic groups were counted. The results showed no difference in the relative arthropod abundance in relation to grazing pressure, but there was weak evidence for higher predator abundance at low and high grazing pressure. The relative arthropod abundance showed a positive trend in organic farms. However, pollinator abundance was higher in conventional farms, and predator abundance did not differ between farming systems. Land-use type was related to the occurrence of predators and pollinators: both groups had the lowest abundance in farmyards compared to cultivated pastures, silage fields, and cereal crop fields. Predator numbers were also higher in silage fields than in the other land-use types. However, there was no significant interaction between land-use types and farming systems in their effect on the arthropod groups. The results suggest that grazing pressure on cultivated grasslands has a minor or negligible impact on arthropod abundance in the two commonest farming systems. However, the effect of farming systems on relative arthropod abundance might be obscured by low sample sizes, high abundance of only a few species, and other variables not included here, such as the use of manure or pesticides. In addition, pollinators included only two taxonomic groups, potentially leading to results not applicable to all pollinators. Consequently, more large-scale studies with higher sample sizes and the inclusion of arthropod diversity and data on the key on-farm practices and landscape structure are needed to disentangle the relationship between biodiversity and grazing on cultivated grasslands in Finland.
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(2020)As a result of urbanization and climate change, cities are facing various ecological and social challenges. For instance, flooding, pollution, urban heat island, decreased biodiversity, and mental stress of city dwellers are well recognized challenges of urban spaces. Urban green spaces are increasingly important in mitigating the adverse effects of climate change, such as flooding due to precipitation extremes, and also providing various other ecosystem services. In order to ensure sustainable land use and provision of ecosystem services, it is essential to develop methods for effective urban green space mapping. As a result, there is a growing demand for micro-scale land cover maps for urban areas. Emerging technologies, such as Object Based Image Analysis, OBIA, and light detection and ranging, LiDAR, offer promising possibilities for efficient mapping of green spaces in the urban environment. The aim of this thesis was to develop a semi-automatic method for urban green space mapping and classification. The other major task was to study the added benefits of light detection and ranging technology. Three research sites of varying degree of urbanization from the city of Helsinki were chosen for the study; from the city core in Itä-Pasila to appartment area with blocks of flats in Pihlajamäki and small-house residential area in Veräjämäki. The classification process was executed with an image analysis program called Definiens Developer. Main input data for classification was LiDAR data and VHR (very high resolution) aerial images. In the classification process, normalized vegetation index (NDVI) was used to detect live vegetation; assignation to different classes was based on height information derived from LIDAR data. Finally, an accuracy assessment was performed on the classified images to determine how well the classification process accomplished the task. The accuracy was assessed by comparing the classification images to the reference images of each catchment. Results demonstrate well the potential of OBIA for extracting urban green spaces. The downtown area of high land use intensity (Itä-Pasila) had the smallest green space coverage (31%), consisting mostly of urban parks and planted trees along the streets. The small-house area of low land use intensity (Veräjämäki) had the highest proportion (65%) of green spaces, consisting of forests and gardens. In the intermediate land use intensity with block of flats (Pihlajamäki)ts, a little under half of the coverage is green spaces. The highest accuracy of detecting green spaces was reached in low land use intensity area (92%), followed by the high and intermediate land use areas with 82% and 78%, respectively. The most common problem for classification was shaded areas, which reflect only limited spectral information and therefore the calculating of NDVI index becomes impossible. I found the object-based image analysis together with LiDAR data fusion to provide good means for urban green space mapping and classification. The presented method allowed a quick data acquisition with good overall accuracy, while avoiding the problems previously related to more traditional pixel-based methods. The addition of LiDAR data created the possibility of extracting vegetation height and using it in the classification process in order to divide vegetation into four different classes.
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(2022)The ongoing growth and densification of urban areas is threatening biodiversity in cities. Previously continuous habitats are reduced and fragmented into smaller areas, which increases the edge effect and changes the qualities of the original habitat. Urban greenspaces are frequently used by people, and disturbances, such as trampling, and understorey management are increasing the similarity of habitat patches (i.e. homogenisation). In this study, I investigated the effects of small-scale homogeneity in forests produced by urbanisation on the distribution patterns and trait composition of carabid beetles. Sampling was done with pitfall traps during the summer of 2021 and altogether 21 study sites were selected in the City of Lahti, Finland. The study sites represented three different environments: 1) structurally complex (heterogenous) habitat in remnant spruce forests in the city, 2) structurally simple (homogenous) habitat in remnant spruce forests in the city, 3) structurally simple habitat under spruce trees in managed urban parks. In addition to the beetles, a set of environmental variables was collected to quantify the complexity of the three habitat types. As expected, habitat homogeneity affected carabid beetle species composition so that the proportion of generalist and open-habitat species was greater in homogenous sites, including homogenous forest remnants and highly homogenous urban parks, whereas the proportion of forest specialists was greater in heterogenous forests. Species richness was higher in the homogenous sites due to species-rich open-habitat genera in the carabid beetle family. Trait distribution at the community level showed clear differences between the three studied habitat types. As expected, the proportions of large and heavy species were higher in the forest habitats than in the parks, whereas homogenous habitats, especially highly homogenous park sites consisted of a higher proportion of flight capable species than heterogenous forests. At the species level, individual beetles were generally smaller in the parks, whereas the results between the two forest types varied and a clear difference between habitat specialists and generalists could not be detected. As cities grow, keeping the management of greenspaces moderate, selecting native vegetation, and preserving decaying woody material are ways to increase habitat heterogeneity, which according to this study, can support biodiversity and life of different organisms in urban areas.
Now showing items 1-7 of 7