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Legacy effects of spring temperature anomalies on seasonal productivities in northern ecosystems Direct and lagged effects from spring temperature anomalies for the time-period 2001-2018 have been investigated for northern ecosystems (> 30°N). Three different data sets of Gross Primary Production (GPP) estimates (GOSIF, NIRvGPP and FLUX GPP) have been used in tandem with concurrent climate data
Tropical forests are of great importance to all living-beings due to their high biodiversity and the valu-able resources, such as food and fuel, they provide. In addition, tropical trees sequester a high amount of carbon and consequently over half of the global forest carbon stock can be found in the tropics. Climate change, however, might weaken this carbon sink and possibly result in tropical fo
Shabestar basin in the East Azerbaijan province, Northwest Iran, where irrigation is the main groundwater consumer, has experienced large-scale subsidence and groundwater deletion, which poses a threat to the local agricultural activities, economic development, and food security. With the emergency of mitigating the risk, satisfying future demand for groundwater, and improving resilience consideri
Due to climate change, cities are increasingly facing the situation of being exposed to more frequent and prolonged extreme weather events in the future, such as heat and droughts, which are exacerbated by urban heat island (UHI) effects. The implementation of green infrastructure (GI) in the form of trees is seen as a possible adaptation measure to regulate the microclimate. However, there is an
3D city models are valuable tools for visualization and analytical purposes in the urban environment. A popular format for city models is CityGML, an open data model that can be used for storage and exchange of 3D city models. However, using city models based on CityGML has appeared to be a challenge as there is a limited number of software applications that are able to read them. Complexity in Ci
Methane is one of the most important greenhouse gases, and the Arctic region plays an important role in its dynamics. Due to limited observations in this remote and often harsh environments, large uncertainties surround the role of the Arctic region in a warming climate. In this thesis, I examine the performance of the three low-cost solid state sensors, Figaro sensors TGS2600-B00, TGS2611-C00 an
Geographic Information Systems (GIS) have acquired greater relevance as tools to support decision-making processes, and during the last decades they have been used in conjunction with Multi-Criteria Decision Analysis techniques (GIS-MCDA) to solve real-world spatial problems. GIS-MCDA can be generally divided in Multi-Attribute and Multi-Objective techniques. Until now most of the applications of
Central Africa has the lowest food production per capita, slow yield development and the fastest growing population in the world. This study aimed to develop a model, which estimates the grain surplus or deficit in Cameroon for 2015-2030. Grains form the main diet in Cameroon and the modelled grains in this project are sorghum, millet, rice and maize. Additionally, in the case of a deficit, the yi
Geographic information system multi-criteria decision analysis (GIS-MCDA) procedure can combine criterion maps together and associated the criterion weights to acquire an overall value for each spatial location in the research area. Analytical Hierarchy Process (AHP), Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS), Ordered Weighted averaging (OWA) are three generic algo
Considering the growing pressure on various ecosystems all around the world, the development of ecological indicators for assessing the health and condition of the ecosystems has become an integral part of environmental management and policy making efforts. Such indicators do not only simplify the complex ecosystem processes but can also act as a measure of performance of a conservation policy. Th
The Normalized Vegetation Difference Index (NDVI) is frequently used as a surrogate for vegetation properties and is often correlated with climatic variables such as rainfall. However, studies have shown that conventional regression models used to study the spatial relationship between NDVI and rainfall are often plagued by non-stationarity and are scale dependent. This thesis employed a spatial d
Disease susceptibility mapping can produce risk maps showing predictive distribution of disease incidences. Hence, it is a useful tool for disease prevention. Data-driven approaches for disease susceptibility mapping model relationships and patterns from experience data. Therefore, using data-driven methods can facilitate a simple and direct approach towards disease susceptibility mapping. In th
Forest biomass acts as an important indicator of carbon resources in terrestrial system. Estimation of forest biomass enables a straightforward measurement of carbon storage and provides initial values for process-based carbon cycle models to simulate carbon dynamics. LiDAR (Light Detection and Ranging) remote sensing is increasingly used to estimate forest biomass because of its ability to detect
The decreasing extent of the Arctic sea ice has opened up new areas in the High North for industrial and commercial activities. These areas contain large reserves of oil and gas, and the region is home to some of the world’s richest fishing grounds. The region is of key strategic importance, and maintaining a Norwegian presence in the Arctic areas is considered to be a national priority. A major r
Agriculture is an essential economic activity which sustains the livelihood of millions of people around the world. Maize is one of the most grown, consumed and traded cereals in the world mostly because of its adaptability to varied environmental conditions. Maize farming depends on climatic factors like temperature, rainfall and radiation to thrive but this also means that it is very susceptible
The aim of this thesis is to investigate the following: − The influence of incident angle and frequency dependency of a ceiling absorber on room acoustic descriptors − How ceiling absorber properties influence room acoustic descriptors such as reverberation time and steady state sound pressure level − Whether steady state sound pressure level is more related to the statistical absorption coeffici
Ecosystem services have been widely discussed as of late, and more so than ever, has the topic of resilience and sustainable city planning taken an important role in the debate over how we can meet the present challenges concerning livable cities. The costs and the benefits of urban trees is an important factor in sustainable city planning and their consideration early in the planning stages canno
Active volcanoes threaten life around. In order to predict their eruptions earlier and mitigate their hazards, several variables must be observed and compared. Geographical information systems (GIS) combine different geospatial images from remote or local sensing. However, GIS often miss how maps change during the time. In this thesis Wisdom-volkano is presented, a web GIS based on open source sta
Estimation of GPP in Sudan using the evaporative fraction as water stress factor The Gross Primary Production "GPP" quantifies the amount of carbon entering an ecosystem. It is an ecosystem service since it is a source of energy for all organisms and it is estimated to reduce atmospheric CO2 in about 123 Pg C per year at the global scale. Therefore, the improvement of estimation methods
Introduction The aim of this study is to determine the locations for school construction in two isolated mountainous communities in Gorno-Badakhshan Autonomous Oblast (GBAO) – Khorog and Porshnev towns. In recent decades, this region has become increasingly vulnerable to natural disasters. A major contributing factor to this vulnerability is the fact that very little land is available for human se
