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1.	Caretta, Martina Angela, et al. (författare) Water 2022 Ingår i: Climate Change 2022: Impacts, Adaptation and Vulnerability : Contribution of Working Group II to the Sixth Assessment Report of the Intergovernmental Panel on Climate Change - Contribution of Working Group II to the Sixth Assessment Report of the Intergovernmental Panel on Climate Change. Bokkapitel (övrigt vetenskapligt/konstnärligt)
2.	Fazel, Nasim, et al. (författare) Regionalization and spatial analysis of precipitation of the Urmia Lake Basin, Iran 2015 Ingår i: World Environmental and Water Resources Congress 2015 : Floods, Droughts, and Ecosystems - Proceedings of the 2015 World Environmental and Water Resources Congress - Floods, Droughts, and Ecosystems - Proceedings of the 2015 World Environmental and Water Resources Congress. - Reston, VA : American Society of Civil Engineers. - 9780784479162 ; , s. 1101-1107 Konferensbidrag (refereegranskat)abstract The spatial patterns of precipitation regarding physiography and atmospheric circulations in the Lake Urmia Basin have been investigated. Daily rainfall time series for the 50 most reliable precipitation stations for the period 1980-2010 were analyzed to detect the regional precipitation pattern. To identify rainfall homogeneous regions, principal component analysis was applied to the precipitation dataset. Agglomerative hierarchical clustering analysis using the Ward and Euclidean distance methods revealed three distinctive precipitation regions in the basin influenced by topography and lake. The first region (G1) covers the north and northeastern part of the Lake Urmia. G2 includes stations located in south and southeastern part of the basin, while G3 covers the western part of the lake basin. The results from this study can be used to better plan agricultural land use, cropping patterns and water management in the delineated homogeneous rainfall regions.
3.	Fazel, Nasim, et al. (författare) Regionalization of precipitation characteristics in Iran's Lake Urmia basin 2018 Ingår i: Journal of Theoretical and Applied Climatology. - : Springer Science and Business Media LLC. - 0177-798X .- 1434-4483. ; 132:1-2, s. 363-373 Tidskriftsartikel (refereegranskat)abstract Lake Urmia in northwest Iran, once one of the largest hypersaline lakes in the world, has shrunk by almost 90% in area and 80% in volume during the last four decades. To improve the understanding of regional differences in water availability throughout the region and to refine the existing information on precipitation variability, this study investigated the spatial pattern of precipitation for the Lake Urmia basin. Daily rainfall time series from 122 precipitation stations with different record lengths were used to extract 15 statistical descriptors comprising 25th percentile, 75th percentile, and coefficient of variation for annual and seasonal total precipitation. Principal component analysis in association with cluster analysis identified three main homogeneous precipitation groups in the lake basin. The first sub-region (group 1) includes stations located in the center and southeast; the second sub-region (group 2) covers mostly northern and northeastern part of the basin, and the third sub-region (group 3) covers the western and southern edges of the basin. Results of principal component (PC) and clustering analyses showed that seasonal precipitation variation is the most important feature controlling the spatial pattern of precipitation in the lake basin. The 25th and 75th percentiles of winter and autumn are the most important variables controlling the spatial pattern of the first rotated principal component explaining about 32% of the total variance. Summer and spring precipitation variations are the most important variables in the second and third rotated principal components, respectively. Seasonal variation in precipitation amount and seasonality are explained by topography and influenced by the lake and westerly winds that are related to the strength of the North Atlantic Oscillation. Despite using incomplete time series with different lengths, the identified sub-regions are physically meaningful.
4.	Gunnarsdottir, Maria J., et al. (författare) Status of risk-based approach and national framework for safe drinking water in small water supplies of the Nordic water sector 2020 Ingår i: International Journal of Hygiene and Environmental Health. - : Elsevier BV. - 1438-4639. ; 230 Tidskriftsartikel (refereegranskat)abstract Reliable safe water supply is a pillar of society and a key to public health. The Nordic countries have an abundance of clean fresh water as a source for drinking water supplies. They have followed developments in safeguarding water, both the recommendations of the World Health Organization framework for safe drinking water and European legislation. Worldwide, including the Nordic countries, small water supplies are less compliant with water safety regulation. The forthcoming EU directive on drinking water require risk-based approaches and improved transparency on water quality. This research looks at the Nordic frameworks for safe water supply, with emphasis on risk-based approaches and smaller systems. We analyzed the legal frameworks for safe water, the structure of the water sector across the Nordic countries and explored how prepared these countries are to meet these requirements. Our findings show that, while legal requirements are mostly in place, delivery of information to the public needs to be improved. Most Nordic countries are in the process of implementing risk-based management in large and medium size water supplies, whereas small supplies are lagging. We conclude that a key to success is increased training and support for small supplies. We suggest wider adoption of the Nordic model of cooperation with benchmarking of safe water for all to transfer knowledge between the countries. This work provides insights into challenges and opportunities for the Nordic countries and provides insights relevant to countries worldwide in their effort towards realization of SDG Target 6.1.
5.	Haghighi, Ali Torabi, et al. (författare) When rain does not run, a fingerprint of uncoordinated water resources development 2024 Ingår i: Journal of Hydrology. - 0022-1694. ; 629 Tidskriftsartikel (refereegranskat)abstract The management of water resources in a basin can be challenging due to the sharing of water resources among multiple stakeholders and conflicting interests. This often results in imbalanced water resource development across the basin. While small and medium-sized projects are efficiently implemented in the headwater and upstream areas, the commissioning of large reservoirs faces delays due to the substantial investment required and regulatory processes involved. Also, the lack of coordination and synchronization in water resource development between upstream and downstream regions can lead to water scarcity and inefficient utilization of resources in the lower part of the basin. In this study, we assess the occurrence of water scarcity by comparing the frequency of hydrological and meteorological droughts before and after the detected abrupt change in river flow. To facilitate this assessment, we introduced two new indices: the positive to negative phases of hydrological and meteorological droughts. These indices highlight the increasing occurrence of hydrological droughts, which may not necessarily be linked to meteorological droughts during the identified periods. Furthermore, we propose a Monotone drought analysis method to examine the correlation between meteorological and hydrological droughts and address the impact of anthropogenic activities. We applied this analysis in the Sefid-Rud basin, the largest sub-basin in the southern Caspian Sea situated in Iran, which hosts several dams and reservoirs while more dams are in the construction and planning phase. The assessment took place in 24 gauges across the basin from 1978 to 2017 to detect and evaluate the alterations in flow regimes. Our analysis revealed that the unbalanced development of upstream water resources, driven by uncoordinated water infrastructure projects implemented by various decision-makers, has resulted in a decline of available water at critical points within the basin, which will be aggravated with the commissioning of new dams.
6.	Huang, Xiao, et al. (författare) The MYR Project (2018-21): Climate smart management practices on Norwegian organic soils 2019 Ingår i: Geophysical Research Abstracts Vol. 21, EGU2019-7918, 2019. Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract Cultivated organic soils account for∼7% of Norway’s agricultural land area, and they are estimated to be a significant source of greenhouse gas (GHG) emissions. The project ‘Climate smart management practices on Norwegian organic soils’ (MYR), commissioned by the Research Council of Norway (decision no. 281109), aims to evaluate GHG (e.g. carbon dioxide, methane and nitrous oxide) emissions and impacts on biomass productivity from three land use types (cultivated, abandoned and restored) on organic soils. At the cultivated sites, impacts of drainage depth and management intensity will be measured. We established experimental sites in Norway covering a broad range of climate and management regimes, which will produce observational data in high spatio-temporal resolution during 2019-2021. Using state-of-the-art modelling techniques, MYR aims to predict the potential GHG mitigation under different scenarios. Four models (BASGRA, DNDC, Coup and ECOSSE) will be further developed according to the soil properties, and then used independently in simulating biogeochemical processes and biomass dynamics in the different land uses. Robust parameterization schemes for each model will be based in the observational data from the project for both soil and crop combinations. Eventually, a multi-model ensemble prediction will be carried out to provide scenario analyses by 2030 and 2050. By integrating experimental results and modelling, the project aims at generating useful information for recommendations on environment-friendly use of Norwegian peatlands.
7.	Iranezhad, Masoud, et al. (författare) Hydrological Feasibility of Flood Barriers to Protect the Gothenburg (Sweden) during the 21st Century - An Initial Assessment 2014 Ingår i: Conference: XXVIII Nordic Hydrological Conference, Nordic Water 2014: The Nordic Hydrology Model - Linking science and practice, At Stockholm, Sweden, 11-13 August 2014. Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract Climate change due to increasing of greenhouse gas emissions to the atmosphere will cause mean sea level to rise about +1 m by 2100. To prevent coastal floods resulted from the sea level rising, different flood control structures have been built and showed acceptable protection levels at least so far; e.g. Thames Barrier in London, UK. Gothenburg city on the south-west coast of Sweden, with the Göta älv River running through it, is one of vulnerable cities to the accelerated sea level rise. Besides, a high tide in southern Sweden will be increased to +2 m above the current sea level by 2100. Hence, most parts of Gothenburg will experience flooding events during the 21st century, even the City Planning Office of Gothenburg suggests +2.5 m above the current sea level as the safe level for setting the shelter of especially important facilities by 2100. Developing water level model by MATLAB, we investigated the hydrological feasibility of using flood barriers in the Göta älv River to protect the Gothenburg city against flooding events during this century. One flood control barrier at the river upstream (upstream barrier) in the Gothenburg region and a sea barrage (Göta älv barrage) at the entrance point of the river to the North Sea were suggested by this study. Considering three operational scenarios for these barriers, the highest sea level was estimated to +2.95 m above the current mean sea level by 2100. To prove flood protection against such high sea levels, both barriers have to be closed. In order to prevent high water levels in the Göta älv reservoir due to the runoff generation from rainfall, the barriers would be open when the sea level is low. This preliminary assessment concluded the suggested sea and flood barriers would successfully protect the Gothenburg city from flooding events during the 21st century.
8.	Irannezhad, Masoud, 1983, et al. (författare) Analysing the variability and trends of precipitation extremes in Finland and their connection to atmospheric circulation patterns 2017 Ingår i: International Journal of Climatology. - : Wiley. - 0899-8418 .- 1097-0088. ; 37, s. 1053-1066 Tidskriftsartikel (refereegranskat)abstract © 2017 Royal Meteorological Society Ten precipitation indices recommended by the Expert Team on Climate Change Detection and Indices were used to analyse spatial distribution and temporal changes in annual amount, intensity, frequency and duration of precipitation statistics based on daily data with a focus on extremes in Finland during 1 961–2011. Also, the connections between these high resolution (10 km) precipitation indices and six influential atmospheric circulation patterns (ACPs) for climate variability in Finland were studied. On the country scale, the results suggest significant increases in the amount and intensity of precipitation extremes, more precipitation days, and no clear changes in wet and dry spells. Both intensity and frequency of precipitation extremes over Finland decrease from south and southwest to north. The only exception is the distribution of precipitations days which is generally more frequent over eastern and upper areas of northern Finland. Wet (dry) spells were typically longer in the western (eastern) part of Finland. Significant increases in annual total wet-day precipitation, very wet days precipitation and simple daily intensity index were found over most parts of Finland during 1961–2011. Increasing trends in both extremely wet days and maximum 1-day precipitation were mostly observed in western, eastern, central and northern Finland. Such spatial pattern was also identified for significant increases in the frequency of heavy and very heavy precipitation days. The precipitation days increased over small parts of western, eastern and northern Finland. Wet spells showed lengthening trends in several grids over southwestern Finland, while dry spells lengthened in some areas over the entire country except southern parts. These variations in precipitation statistics were found to be significantly correlated with the East Atlantic/West Russia, East Atlantic, Scandinavia and Polar patterns.
9.	Irannezhad, Masoud, et al. (författare) Century-long variability and trends in daily precipitation characteristics at three Finnish stations 2016 Ingår i: Advances in Climate Change Research. - : Elsevier BV. - 1674-9278. ; 7, s. 54-69 Tidskriftsartikel (refereegranskat)abstract © 2016 National Climate Center (China Meteorological Administration) Long-term variations and trends in a wide range of statistics for daily precipitation characteristics in terms of intensity, frequency and duration in Finland were analysed using precipitation records during 1908–2008 from 3 meteorological stations in the south (Kaisaniemi), centre (Kajaani) and north (Sodankylä). Although precipitation days in northern part were more frequent than in central and southern parts, daily precipitation intensity in the south was generally higher than those in the centre and north of the country. Annual sum of very light precipitation (0 mm < daily precipitation ≤ long-term 50th percentile of daily precipitation more than 0 mm) significantly (p < 0.05) decreased over time, with the highest rate in northern Finland. These decreasing trends might be the result of significant increases in frequency of days with very light precipitation at all the stations, with the highest and lowest rates in northern and southern Finland, respectively. Ratio of annual total precipitation to number of precipitation days also declined in Finland over 1908–2008, with a decreasing north to south gradient. However, annual duration indices of daily precipitation revealed no statistically significant trends at any station. Daily precipitation characteristics showed significant relationships with various well-known atmospheric circulation patterns (ACPs). In particular, the East Atlantic/West Russia (EA/WR) pattern in summer was the most influential ACP negatively associated with different daily precipitation intensity, frequency and duration indices at all three stations studied.
10.	Irannezhad, MASOUD, et al. (författare) THE ROLE OF ATMOSPHERIC CIRCULATION PATTERNS IN AGROCLIMATE VARIABILITY IN FINLAND, 1961–2011 2016 Ingår i: Geografiska Annaler, Series A: Physical Geography. - : Informa UK Limited. - 0435-3676 .- 1468-0459. ; 98:4, s. 287-301 Tidskriftsartikel (refereegranskat)abstract © 2016 Swedish Society for Anthropology and GeographyThis study evaluates interannual variations and trends in growing season daily temperature sum and daily precipitation sum in Finland during 1961–2011, and their connections to well known atmospheric circulation patterns. Changes in summer (June–August) climate partially explain changes in growing season daily temperature sum and daily precipitation sum over Finland, which naturally decreased from south to north. On a national scale, growing season warmed and became wetter during 1961–2011, as growing season daily temperature sum and daily precipitation sum significantly (p < 0.05) increased by 5.01 ± 3.17°C year–1 and 1.39 ± 0.91 mm year–1, respectively. The East Atlantic pattern was the most influential atmospheric circulation pattern for variations in growing season daily temperature sum (rho = 0.40) across Finland and the East Atlantic/West Russia pattern was most influential for growing season daily precipitation sum variability (rho = –0.54). There were significant (p < 0.05) increasing trends in growing season daily temperature sum and daily precipitation sum throughout Finland during 1961–2011. Increased growing season daily temperature sum was mainly observed in northern, central, western, eastern and coastal areas of south-western Finland. This warming was positively associated with the East Atlantic pattern in the north, centre and south, but negatively associated with the East Atlantic/West Russia pattern in eastern Finland. Increased GSP mostly occurred in southern, eastern, western, central, northern and north-western Finland. These wetting trends were positively correlated with the East Atlantic pattern in the north and negatively correlated with the Polar pattern in the south and the East Atlantic/West Russia pattern in the east, west, centre and north-east of Finland. The overall agroclimatic year-to-year variability in Finland between 1961 and 2011 was mostly linked to variations in the East Atlantic and East Atlantic/West Russia patterns.
11.	Kjellin, Johan, 1978- (författare) Coupled Hydrological and Microbiological Processes Controlling Denitrification in Constructed Wetlands 2007 Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract Treatment wetlands play an important role in reducing nitrogen content in wastewater and agricultural run-off water. The main removal process is denitrification and the removal efficiency depends on the hydrological and microbiological features of the wetland, especially in terms of water residence times and denitrification rates. The aim of this thesis was to increase the understanding of the coupled hydrological and microbiological processes regulating the denitrification capacity. This was done by applying a broad spectrum of analyses methods, including tracer experiment, water flow modeling, denitrification rate measurements, and analyses of the microbial community structures. The tracer experiment and flow modeling revealed that the wetland design, especially the vegetation, largely can affect the water residence time distributions in wetlands. In the investigated wetland, vegetation dominated the water flow, explaining 60-80% of the variance in water residence times, whereas basin shape only explained about 10% of the variance, but also mixing phenomena significantly affected the residence times and could considerably delay solutes. Measured potential denitrification rates in the wetland exhibited significant spatial variations, and the variations were best described by concentration of nitrogen in sediments and water residence time. Analyses of the denitrifying bacteria populations indicated that a few key populations dominated and that the community diversity increased with decreasing nutrient levels and increasing water residence times. Moreover, it was found that denitrification rates in terms of Menten and first order kinetics can be evaluated by fitting a mathematical expression, considering denitrification and other nitrogen transforming processes to measured product formation in nitrate limited experiments.
12.	Kløve, Bjørn (författare) Environmental impact of peat mining : Development of storm water treatment methods 1997 Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract Drainage of peatlands increases the transport of suspended solids (SS) and the leaching of nutrients to downstream receiving waters. Increased settling of peat and eutrophication of lakes has been noted in many studies downstream from peat mines. Treatment alternatives have therefore been developed since the early 1980s to reduce the environmental impacts of peat mining. New, efficient methods such as artificial wetlands, chemical treatment and infiltration techniques have been developed, although, in most cases, they have been either too expensive to be used at all peat mines or they have failed to function during high hydraulic loads when the majority of the SS and nutrients are borne by drainage water. The aim of this series of studies has been to develop methods that function when the pollution load is high and that are economically viable for all peat mines. Sediment transport and nutrient leaching were studied with the purpose of establishing more efficient treatment alternatives. A controlled experiment was set up to measure the erosion of peat from the soil surface and from ditch beds during heavy rainfall and runoff events and to measure the settling characteristics of base soil peat and peat deposited in channels. The study demonstrates the importance of channel bed erosion as the main source of sediments during peak runoff. Sediment transport and nutrient leaching were further observed in the field during 1995 and 1996. The study showed that SS is mainly generated during extreme events, such as flooding, when external water from the surrounding uplands flows into the mine and snowmelt. These high flow events erode the material deposited on the channel bed during low flows. The leaching of nitrogen occurs after large rain events when newly infiltrated water, rich in nitrate, reaches the drainage area outlet. High phosphorus concentrations occur when the water-table is low and the groundwater fed baseflow is older and rich in humus. Treatment alternatives were developed to improve removal of SS and nutrients. Different types of ponds (rectangular, compartmental and circular) were tested in a laboratory down-scaled study. The study showed that the main factor affecting the settling of small peat particles is the depth of the settling basin rather than the type of basin. Therefore, artificial floodplains were suggested as a preferred treatment alternative. A mathematical model study showed that in the case of bare soil erosion, the best treatment alternative would be to store the water in the large drainage network rather than in the sedimentation basins which have a substantially smaller capacity. Different structures suitable for peak runoff control were tested under laboratory and in field conditions. The most important results from the thesis are that the structures developed function well and reduce peak flows from peat mines and, hence, reduce ditch bed erosion and SS load.
13.	Kløve, Bjørn, et al. (författare) Groundwater dependent ecosystems : Part I: Hydroecological status and trends 2011 Ingår i: Environmental Science and Policy. - : Elsevier BV. - 1462-9011 .- 1873-6416. ; 14:7, s. 770-781 Tidskriftsartikel (refereegranskat)abstract Groundwater dependent ecosystems (GDEs) include valuable ecosystems such as springs, wetlands, rivers, lakes and lagoons. The protection of these systems and services they provide is highlighted by international agreements, i.e. Ramsar convention on wetlands, and regional legislation, i.e. the European Water Framework Directive. Groundwater provides water, nutrients and a relatively stable temperature. However, the role of groundwater in surface ecosystems is not fully understood. The ecosystem can depend on groundwater directly or indirectly, and the reliance can be continuous, seasonal or occasional. This has implications for the vulnerability of ecosystems, as some may be easily affected by external pressure. Conceptual models and quantitative assessments of how groundwater interacts with the environment are needed. GDEs are also threatened by different land use activities and climate change. Hence, we need to understand how GDEs are affected by changes in groundwater quantity and quality, as severe groundwater changes have been observed in many regions. This study examines key aspects of GDEs (hydrogeology, geochemistry and biodiversity) in order to improve conceptual understanding of the role of groundwater in such ecosystems. The status and baseline of different types of GDEs are discussed, with particular emphasis on past evidence of environmental change and potential thresholds and threats in GDEs in various parts of Europe with different land use, climate and geology
14.	Kløve, Bjørn, et al. (författare) Groundwater dependent ecosystems. Part II. Ecosystem services and management in Europe under risk of climate change and land use intensification 2011 Ingår i: Environmental Science and Policy. - : Elsevier BV. - 1462-9011 .- 1873-6416. ; 14:7, s. 782-793 Tidskriftsartikel (refereegranskat)abstract Groundwater in sufficient amounts and of suitable quality is essential for potable water supplies, crop irrigation and healthy habitats for plant and animal biocenoses. The groundwater resource is currently under severe pressure from land use and pollution and there is evidence of dramatic changes in aquifer resources in Europe and elsewhere, despite numerous policy measures on sustainable use and protection of groundwater. Little is known about how such changes affect groundwater dependent ecosystems (GDEs), which include various aquatic and terrestrial ecosystems above ground and inside the aquifer. Future management must take this uncertainty into account. This paper focuses on multiple aspects of groundwater science, policy and sustainable management. Examples of current management methods and practices are presented for selected aquifers in Europe and an assessment is made of the effectiveness of existing policies such as the European Water Framework Directive and the Habitat Directive in practice and of how groundwaters and GDEs are managed in various conditions. The paper highlights a number of issues that should be considered in an integrated and holistic approach to future management of groundwater and its dependent ecosystems.
15.	Kløve, Bjørn, et al. (författare) Groundwater surface water interaction in GDE 2012 Rapport (populärvet., debatt m.m.)abstract This report reviews and discussed the interaction of groundwaterin GDEs. The report presents and integrates past and new results.Different methods used to measure groundwater interaction withecosystems are presented. Various GENESIS case studies acrossEurope to demonstrate the variable and complex role ofgroundwater in GDEs. The basis for developing conceptual for GDEsis presented. Various methods to model GDEs are discussed.
16.	Kløve, Bjørn, et al. (författare) Protection of GDE related ecosystem services in future groundwater resources management: current policies, methods and future recommendations 2013 Rapport (populärvet., debatt m.m.)abstract Groundwater dependent ecosystems have a high biodiversity and many ecosystem services and their future protection is important. At present, little information is available on the role of groundwater in ecosystems let alone criteria for ecosystem protection. This report makes a critical analysis of present knowledge and seeks for new ways to understand and manage these systems. This is needed to manage groundwater bodies as intended in the European water directives (GWD and WFD) that strive to improve the status of groundwater and surface water. The report includes issues such as sustainability, legal issues, conceptual models, risk valuation and impact assessment methods.
17.	Larsson, Rolf, et al. (författare) Coordination of water policies for quality and quantity : experiences from Nordic and Baltic countries 2022 Ingår i: Hydrology Research. - : IWA Publishing. - 1998-9563 .- 0029-1277 .- 2224-7955. ; 53:9, s. 1166-1185 Tidskriftsartikel (refereegranskat)abstract The European Union (EU) Water Framework Directive is of paramount importance for water management. According to the legal text, coordination with other directives like the Floods Directive is imperative and motivated by potential synergy effects. In this paper, the degree to which such coordination is achieved is evaluated for five Nordic and Baltic countries. The evaluation is based on legal documents, management plans, as well as on organizational structure in the five countries. The results show that the coordination between the Water Framework Directive and the Floods Directive (or flood management for Norway's case), have been successful for Estonia and Lithuania, whereas Norway, Finland, and especially Sweden need to improve more.
18.	Lundberg, Angela, et al. (författare) Snow and frost : implications for spatiotemporal infiltration patterns - a review 2016 Ingår i: Hydrological Processes. - : Wiley. - 0885-6087 .- 1099-1085. ; 30:8, s. 1230-1250 Tidskriftsartikel (refereegranskat)abstract Vast regions of the northern hemisphere are exposed to snowfall and seasonal frost. This has large effects on spatiotemporal distribution of infiltration and groundwater recharge processes as well as on the fate of pollutants. Therefore, snow and frost need to be central inherent elements of risk assessment and management schemes. However, snow and frost are often neglected or treated summarily or in a simplistic way by groundwater modellers. Snow deposition is uneven, and the snow is likely to sublimate, be redistributed and partly melt during the winter influencing the mass and spatial distribution of snow storage available for infiltration, the presence of ice layers within and under the snowpack and, therefore, also the spatial distribution of depths and permeability of the soil frost. In steep terrain, snowmelt may travel downhill tens of metres in hours along snow layers. The permeability of frozen soil is mainly influenced by soil type, its water and organic matter content, and the timing of the first snow in relation to the timing of sub-zero temperatures. The aim with this paper is to review the literature on snow and frost processes, modelling approaches with the purpose to visualize and emphasize the need to include these processes when modelling, managing and predicting groundwater recharge for areas exposed to seasonal snow and frost
19.	Lundberg, Angela, et al. (författare) Spatiotemporal Variations in Snow and Soil Frost : A Review of Measurement Techniques 2016 Ingår i: Hydrology. - : MDPI AG. - 2306-5338. ; 3:3 Tidskriftsartikel (refereegranskat)abstract Large parts of the northern hemisphere are covered by snow and seasonal frost. Climate warming is affecting spatiotemporal variations of snow and frost, hence influencing snowmelt infiltration, aquifer recharge and river runoff patterns. Measurement difficulties have hampered progress in properly assessing how variations in snow and frost impact snowmelt infiltration. This has led to contradicting findings. Some studies indicate that groundwater recharge response is scale dependent. It is thus important to measure snow and soil frost properties with temporal and spatial scales appropriate to improve infiltration process knowledge. The main aim with this paper is therefore to review ground based methods to measure snow properties (depth, density, water equivalent, wetness, and layering) and soil frost properties (depth, water and ice content, permeability, and distance to groundwater) and to make recommendations for process studies aiming to improve knowledge regarding infiltration in regions with seasonal frost. Ground-based radar (GBR) comes in many different combinations and can, depending on design, be used to assess both spatial and temporal variations in snow and frost so combinations of GBR and tracer techniques can be recommended and new promising methods (auocostics and self potential) are evolving, but the study design must be adapted to the scales, the aims and the resources of the study. View Full-Text
20.	Maghrebi, Mohsen, et al. (författare) Iran's Agriculture in the Anthropocene 2020 Ingår i: Earth's Future. - : John Wiley & Sons. - 2328-4277. ; 8:9 Tidskriftsartikel (refereegranskat)abstract The anthropogenic impacts of development and frequent droughts have limited Iran's water availability. This has major implications for Iran's agricultural sector which is responsible for about 90% of water consumption at the national scale. This study investigates if declining water availability impacted agriculture in Iran. Using the Mann‐Kendall and Sen's slope estimator methods, we explored the changes in Iran's agricultural production and area during the 1981‐2013 period. Despite decreasing water availability during this period, irrigated agricultural production and area continuously increased. This unsustainable agricultural development, which would have been impossible without the over‐abstraction of surface and ground water resources, has major long‐term water, food, environmental, and human security implications for Iran.
21.	Nehrenheim, Emma (författare) Industrial by-products in treatment of metals from polluted water 2008 Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract Water treatment can be carried out effectively by passive, low cost methods, as an addition or alternative to existing advanced technology. Energy and resource use can be optimized (i.e. minimized) by reusing by-products from local or regional manufacturing of timber and steel. The ability of pine bark and blast furnace slag to treat metal contaminated water, primarily landfill leachate, has been evaluated. Several issues of concern were addressed in laboratory experiments and pilot scale measurements at a landfill site, including metal adsorption capability, saturation, variables influencing the adsorption process and potential leaching of organic toxicants from pine bark. The data was analyzed using kinetic modeling, regression and multivariate data analysis, i.e. PCA. These experiments showed that pine bark and blast furnace slag have great potential to retain metals from solution. Pine bark could also be used to treat solutions with high concentrations (>200 mg/l) and containing several heavy metals simultaneously (Cu, Pb, Zn, Cr and Ni). A constructed pilot plant showed poor retention of metals, which was somewhat improved by increased contact time, a variable which was found to be important in one of the laboratory experiments. Studies of organic content in landfill leachate, primarily dissolved organic carbon (DOC), showed that this could limit adsorption to pine bark. Another important finding, which is in contrast to the suggestions of other researchers, was that leaching of phenols from pine bark constituted only a small fraction of the DOC and was not toxic to the test-organism Daphnia Magna at neutral pH. In order to understand more about the relationships between the different variables, a multivariate approach (PCA) was applied to data on the treatment of landfill leachate with pine bark. This study showed that the metal concentration of the leachate was the variable most strongly related to metal adsorption. The concentration of DOC had only a minor effect according to PCA. Overall, pine bark and blast furnace slag can be used as adsorbents, but with caution and preferably in effluents of moderate metal concentration and low DOC.
22.	Noori, Roohollah, et al. (författare) Anthropogenic depletion of Iran's aquifers 2021 Ingår i: Proceedings of the National Academy of Sciences of the United States of America. - : Proceedings of the National Academy of Sciences. - 0027-8424 .- 1091-6490. ; 118:25 Tidskriftsartikel (refereegranskat)abstract Global groundwater assessments rank Iran among countries with the highest groundwater depletion rate using coarse spatial scales that hinder detection of regional imbalances between renewable groundwater supply and human withdrawals. Herein, we use in situ data from 12,230 piezometers, 14,856 observation wells, and groundwater extraction points to provide ground-based evidence about Iran’s widespread groundwater depletion and salinity problems. While the number of groundwater extraction points increased by 84.9% from 546,000 in 2002 to over a million in 2015, the annual groundwater withdrawal decreased by 18% (from 74.6 to 61.3 km3/y) primarily due to physical limits to fresh groundwater resources (i.e., depletion and/or salinization). On average, withdrawing 5.4 km3/y of nonrenewable water caused groundwater tables to decline 10 to 100 cm/y in different regions, averaging 49 cm/y across the country. This caused elevated annual average electrical conductivity (EC) of groundwater in vast arid/semiarid areas of central and eastern Iran (16 out of 30 subbasins), indicating “very high salinity hazard” for irrigation water. The annual average EC values were generally lower in the wetter northern and western regions, where groundwater EC improvements were detected in rare cases. Our results based on high-resolution groundwater measurements reveal alarming water security threats associated with declining fresh groundwater quantity and quality due to many years of unsustainable use. Our analysis offers insights into the environmental implications and limitations of water-intensive development plans that other water-scarce countries might adopt.
23.	Noori, Roohollah, et al. (författare) Complex dynamics of water quality mixing in a warm mono-mictic reservoir 2021 Ingår i: Science of the Total Environment. - : Elsevier BV. - 0048-9697. ; 777 Tidskriftsartikel (refereegranskat)abstract Cycling of water quality constituents in lakes is affected by thermal stratification and homo-thermal conditions and other factors such as oligotrophication, eutrophication, and microbial activities. In addition, hydrological variability can cause greater differences in water residence time and cycling of constituents in man-made lakes (reservoirs) than in natural lakes. Thus, investigations are needed on vertical mixing of constituents in new impounded reservoirs, especially those constructed to supply domestic water. In this study, sampling campaigns were conducted in the Sabalan reservoir, Iran, to investigate vertical changes in constituent concentrations during the year in periods with thermal stratification and homo-thermal conditions. The results revealed incomplete mixing of constituents, even during cold months when the reservoir was homo-thermal. These conditions interacted to create a bottom-up regulated reservoir with sediment that released settled pollutants, impairing water quality in the Sabalan reservoir during both thermal stratification and homo-thermal conditions. Analysis of total nitrogen and total phosphorus concentrations revealed that the reservoir was eutrophic. External pollution loads, internal cycling of pollutants diffusing out from bottom sediments, reductions in inflow to the reservoir, and reservoir operations regulated vertical mixing and concentrations of constituents in the Sabalan reservoir throughout the year.
24.	Noori, Roohollah, et al. (författare) PODMT3DMS-Tool : proper orthogonal decomposition linked to the MT3DMS model for nitrate simulation in aquifers 2020 Ingår i: Hydrogeology Journal. - : Springer Science and Business Media LLC. - 1431-2174 .- 1435-0157. Tidskriftsartikel (refereegranskat)abstract The PODMT3DMS-Tool, which consists of a proper orthogonal decomposition (POD) linked to the Modular Transport 3-Dimensional Multi Species (MT3DMS) code for nitrate simulation in groundwater, is introduced. POD, as a statistical technique, reduces a large amount of information produced by the MT3DMS model to provide the main components of the PODMT3DMS-Tool, i.e., space- and time-dependent terms of nitrate. The low-dimensional components represent time- and space-dependent factors in the aquifer response such as hydraulic, hydrogeological and water quality variables represented in the simulation using the MT3DMS model. The PODMT3DMS-Tool is thus a combined statistical and conceptual model with a simple structure and comparable accuracy to MT3DMS. Practical application of the PODMT3DMS-Tool to the Karaj Aquifer in Iran during 6 years revealed agreement between nitrate concentrations simulated by the PODMT3DMS-Tool and MT3DMS, with a mean absolute error of less than 0.5 mg/L in most parts of the aquifer. Moreover, the PODMT3DMS-Tool needed only about 10% of the calculation time required by MT3DMS. The PODMT3DMS-Tool can be used in predict nitrate concentration in the Karaj Aquifer, while its simplicity also makes it highly interesting for other water resources problems.
25.	Noori, Roohollah, et al. (författare) Recent and future trends in sea surface temperature across the persian gulf and gulf of Oman 2019 Ingår i: PLoS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 14:2 Tidskriftsartikel (refereegranskat)abstract Climate change's effect on sea surface temperature (SST) at the regional scale vary due to driving forces that include potential changes in ocean circulation and internal climate variability, ice cover, thermal stability, and ocean mixing layer depth. For a better understanding of future effects, it is important to analyze historical changes in SST at regional scales and test prediction techniques. In this study, the variation in SST across the Persian Gulf and Gulf of Oman (PG&GO) during the past four decades was analyzed and predicted to the end of 21st century using a proper orthogonal decomposition (POD) model. As input, daily optimum interpolation SST anomaly (DOISSTA) data, available from the National Oceanic and Atmospheric Administration of the United States, were used. Descriptive analyses and POD results demonstrated a gradually increasing trend in DOISSTA in the PG&GO over the past four decades. The spatial distribution of DOISSTA indicated: (1) that shallow parts of the Persian Gulf have experienced minimum and maximum values of DOISSTA and (2) high variability in DOISSTA in shallow parts of the Persian Gulf, including some parts of southern and northwestern coasts. Prediction of future SST using the POD model revealed the highest warming during summer in the entire PG&GO by 2100 and the lowest warming during fall and winter in the Persian Gulf and Gulf of Oman, respectively. The model indicated that monthly SST in the Persian Gulf may increase by up to 4.3 °C in August by the turn of the century. Similarly, mean annual changes in SST across the PG&GO may increase by about 2.2 °C by 2100.
26.	Nygren, Michelle, et al. (författare) Changes in seasonality of groundwater level fluctuations in a temperate-cold climate transition zone 2020 Ingår i: Journal of Hydrology. - : Elsevier BV. - 0022-1694 .- 2589-9155. ; 8 Tidskriftsartikel (refereegranskat)abstract In cold (i.e. boreal, subarctic, snowy) climate zones, dynamic groundwater storage is greatly affected by the timing and amount of snowmelt. With global warming, cold climates in the northern hemisphere will transition to temperate. As temperatures rise, the dominant type of precipitation will change from snow to rain in winter. Further, the growing season is prolonged. This has a direct impact on the aquifer recharge pattern. However, little is known about the effect of changing annual recharge regimes on groundwater storage. The present work deduces the impact of shifting climate zones on groundwater storage by evaluating the effect of climate seasonality on intra-annual hydraulic head fluctuations. The work compares intra-annual hydraulic head fluctuations in a temperate-cold climate transition zone (Fennoscandia) from two different periods (1980–1989, 2001–2010). This is done by associating rising vs. declining hydraulic heads with hydrometeorology. Due to the northwards migration of the temperate climate zone, there is a shift in seasonality between the two periods. This has a negative impact on groundwater levels, which are significantly lower in 2001–2010, particularly near the climate transition zone. The results demonstrate that increasing temperatures in cold climate regions may change the seasonality of groundwater recharge, by altering the main recharge period from being snowmelt-dominated (spring) to rain-dominated (winter). Additionally, this is connected to the duration of the growing season, which impedes groundwater recharge. The coupled effect of this on groundwater in the study area has led to a significant decrease in groundwater storage.
27.	Renman, Agnieszka, 1969- (författare) On-site wastewater treatment : Polonite and other filter materials for removal of metals, nitrogen and phosphorus 2008 Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract Bed filters using reactive materials are an emerging technology for on-site wastewater treatment. Chemical reactions transfer contaminants from the aqueous to the solid phase. Phosphorus is removed from domestic wastewater by sorption to filter materials, which can then be recycled to agriculture as fertilisers and soil amendments. This thesis presents long-term column and field-scale studies of nine filter materials, particularly the novel product Polonite®. Phosphorus, nitro-gen and metals were removed by the mineral-based materials to varying degrees. Polonite and Nordkalk Filtra P demonstrated the largest phosphorus removal capacity, maintaining a PO4-P removal efficiency of >95%. Analysis of filter bed layers in columns with downward wastewater flow, showed that phosphorus, carbon and nitrogen content was vertically distributed, with de-creasing values from surface to base layer. Polonite and Filtra P accumulated 1.9-19 g P kg-1. Nitrogen in wastewater was scarcely removed by the alkaline filter materials, but transformation from NH4-N to NO3-N was >90%. Pot experiments with barley (Hordeum vulgare L.) revealed that after wastewater treatment, slags and Polonite could increase plant production. Batch experi-ments and ATR-FTIR investigations indicated that amorphous tricalcium phosphate (ATCP) was formed in the materials, so some of the accumulated PO4-P was readily available to plants. Low heavy metal contents occurred in the materials, showing that they can be applied as soil amend-ments in agriculture without contamination risks. A full-scale treatment system using Polonite as filter material showed an average PO4-P removal efficiency of 89% for a 92-week period, indicat-ing the robustness of the filter bed technology.
28.	van den Berg, Merit, et al. (författare) The PEATWISE project: reducing greenhouse gas emission in drained peatlands while maintaining biomass production 2019 Ingår i: Geophysical Research Abstracts. - 1029-7006 .- 1607-7962. ; 21 Konferensbidrag (övrigt vetenskapligt/konstnärligt)
29.	Wörman, Anders, 1961-, et al. (författare) Kinematic model of solute transport in stream networks : Example with phosphate retention in Morsa watershed, Norway 2004 Ingår i: Archives of Hydro-engineering and Environmental Mechanics. - 1231-3726. ; 51:1, s. 41-53 Tidskriftsartikel (refereegranskat)abstract A theoretical description of reactive solute transport in a network of stream channels is derived by convoluting unit solutions based on a physical representation of transport and topographical information of the distributions of solute load as well as pathways. The theory is applied to a generic analysis of the phosphate export in Morsa watershed due to the load from 620 individual households with a local wastewater treatment. Essential factors for the phosphate export is filtering of the water in stream-bed sediments through a distribution of hyporheic flow paths of various lengths. This generic study indicates that a significant portion of phosphate is retained in the hyporheic zones for a long time. The 90% recovery time following a hypothetical remediation action in the households is expected to be in the order of one decade.

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