Publications
NIBIOs employees contribute to several hundred scientific articles and research reports every year. You can browse or search in our collection which contains references and links to these publications as well as other research and dissemination activities. The collection is continously updated with new and historical material.
2022
Authors
Lisa ParuchAbstract
Microbial water quality is of vital importance for human, animal, and environmental health. Notably, pathogenically contaminated water can result in serious health problems, such as waterborne outbreaks, which have caused huge economic and social losses. In this context, the prompt detection of microbial contamination becomes essential to enable early warning and timely reaction with proper interventions. Recently, molecular diagnostics have been increasingly employed for the rapid and robust assessment of microbial water quality implicated by various microbial pollutants, e.g., waterborne pathogens and antibiotic-resistance genes (ARGs), imposing the most critical health threats to humans and the environment. Continuous technological advances have led to constant improvements and expansions of molecular methods, such as conventional end-point PCR, DNA microarray, real-time quantitative PCR (qPCR), multiplex qPCR (mqPCR), loop-mediated isothermal amplification (LAMP), digital droplet PCR (ddPCR), and high-throughput next-generation DNA sequencing (HT-NGS). These state-of-the-art molecular approaches largely facilitate the surveillance of microbial water quality in diverse aquatic systems and wastewater. This review provides an up-to-date overview of the advancement of the key molecular tools frequently employed for microbial water quality assessment, with future perspectives on their applications.
Authors
P.L. Sullivan S.A. Billings D. Hirmas L. Li X. Zhang S. Ziegler K. Murenbeeld H. Ajami A. Guthrie K. Singha D. Giménez A. Duro V. Moreno A. Flores A. Cueva A.N. Koop E.L. Aronson H.R. Barnard S.A. Banwart R.M. Keen Attila Nemes N.P. Nikolaidis J.B. Nippert D. Richter D.A. Robinson K. Sadayappan Souza de Souza M. Unruh H. WenAbstract
Soils form the skin of the Earth’s surface, regulating water and biogeochemical cycles and generating production of food, timber, and textiles around the world. Changes in soil and its ability to perform a range of processes have important implications for Earth system function, especially in the critical zone (CZ)—the area that extends from the top of the canopy to the bottom of groundwater and that harbors most of Earth’s biosphere. A key aspect of the way soil functions results from its structure, defined as the size, shape, and arrangement of soil particles and pores. The network of pores provides storage space for at least a quarter of Earth’s biodiversity, while the abundance, size and connectivity of the pore space regulates fluxes of heat, water, nutrients and gases that define the physical and chemical environment. Here we review the nature of soil structure, focusing on its co-evolution with the plants and microbes that live within the soil, and the degree to which these processes have been incorporated into flow and transport models. Though it is well known that soil structure can change with wetting and drying events, often oscillating seasonally, the dynamic nature of soil structure that we discuss is a systematic shift that results in changes in its hydro-bio-geochemical function over decades to centuries, timescales over which major changes in carbon and nutrient cycles have been observed in the Anthropocene. We argue that the variable nature of soil structure, and its dynamics, need to be better understood and captured by land surface and ecosystem models, which currently describe soil structure as static. We further argue that modelers and empiricists both are well-poised to quantify and incorporate these dynamics into their studies. From these efforts, four fundamental questions emerge: 1) How do rates of soil aggregate formation and collapse, and their overall arrangements, interact in the Anthropocene to regulate CZ functioning from soil particle to continental scales? 2) How do alterations in rooting-depth distributions in the Anthropocene influence pore structure to control hydrological partitioning, biogeochemical transformations and fluxes, exchanges of energy and carbon with the atmosphere and climate, regolith weathering, and thus regulation of CZ functioning? 3) How does changing microbial functioning in a high CO2, warmer world with shifting precipitation patterns influence soil organic carbon dynamics and void-aggregate profile dynamics? 4) How deeply does human influence in the Anthropocene propagate into the subsurface, how does this depth relate to profile structure, and how does this alter the rate at which the CZ develops? The United Nations has recently recognized that 33% of the Earth's soils are already degraded and over 90% could become degraded by 2050. This recognition highlights the importance of addressing these proposed questions, which will promote a predictive understanding of soil structure.
Abstract
Global land use change has resulted in more pasture and cropland, largely at the expense of woodlands, over the last 300 years. How this change affects soil hydraulic function with regard to feedbacks to the hydrological cycle is unclear for earth system modelling (ESM). Pedotransfer functions (PTFs) used to predict soil hydraulic conductivity (K) take no account of land use. Here, we synthesize >800 measurements from around the globe from sites that measured near-saturated soil hydraulic conductivity, or infiltration, at the soil surface, on the same soil type at each location, but with differing land use, woodland (W), grassland (G) and cropland (C). We found that texture based PTFs predict K reasonably well for cropland giving unbiased results, but increasingly underestimate K in grassland and woodland. In native woodland and grassland differences in K can usually be accounted for by differences in bulk density. However, heavy grazing K responses can be much lower indicating compaction likely reduces connectivity. We show that the K response ratios (RR) between land uses vary with cropland (C/W = 0.45 [W/C = 2.2]) and grassland (G/W = 0.63 [W/G = 1.6]) having about half the K of woodland.
Authors
Nils-Otto Kitterød Jens Kværner Per Aagaard Jurga Arustiene Jānis Bikše Atle Dagestad Pål Gundersen Birgitte Hansen Árni Hjartarson Enn Karro Maris Klavins Andres Marandi Rasa Radiene Inga Retike Pekka M. Rossi Lærke ThorlingAbstract
No abstract has been registered
Abstract
Data compilation of groundwater chemistry and freshwater abstraction documents the importance of groundwater as an economical resource in the Nordic Region. Management of groundwater require chemical monitoring to minimize risks for contamination, and mitigation is needed to identify anthropogenic and geogenic hazards related to groundwater quality (Kitterød et al, 2022). The interaction between groundwater and surface water is crucial for important ecological systems in the Nordic Region, and the impacts of climate change is a big challenge for hydrological and environmental research. The increased net global energy influx has impact on average temperature, seasonality, precipitation, and runoff, but issues related to water quality and groundwater have received less attention. The interaction between surface water and groundwater chemistry is embraced in the term hydrogeochemistry. In this context the geological framework plays a cardinal role in combination with residence time of water in the subsurface. Extensive sampling of hydrogeochemical variables have been undertaken in the Nordic Region and results are made available in public databases. Such data deserve more attention from the research community, and a pertinent challenge is to include geochemical variables in water balance studies and regional hydrological modeling. Reference: Kitterød, N-O, Kværner, J., Aagaard, P, Arustienė, J, de Beer, H, Bikše, J, Dagestad, A, Gundersen, P, Hansen, B, Hjartarson, Á, Karro, E, Klavins, M, Marandi, A, Putys, P, Radienė, R, Retiķe, I, Rossi, P M, and Thorling, L: Hydrogeology and Groundwater Quality in the Nordic Region. Submitted to Hydrology Research, 2022. Keywords: Hydrogeochemsitry; groundwater quality; surface water quality.
Authors
Randika K. Makumbura Miyuru Gunathilake Jayanga T. Samarasinghe Remegio Confesor Nitin Muttil Upaka RathnayakeAbstract
Hydrologic models are indispensable tools for water resource planning and management. Accurate model predictions are critical for better water resource development and management decisions. Single-site model calibration and calibrating a watershed model at the watershed outlet are commonly adopted strategies. In the present study, for the first time, a multi-site calibration for the Soil and Water Assessment Tool (SWAT) in the Kelani River Basin with a catchment area of about 2340 km2 was carried out. The SWAT model was calibrated at five streamflow gauging stations, Deraniyagala, Kithulgala, Holombuwa, Glencourse, and Hanwella, with drainage areas of 183, 383, 155, 1463, and 1782 km2, respectively, using three distinct calibration strategies. These strategies were, utilizing (1) data from downstream and (2) data from upstream, both categorized here as single-site calibration, and (3) data from downstream and upstream (multi-site calibration). Considering the performance of the model during the calibration period, which was examined using the statistical indices R2 and NSE, the model performance at Holombuwa was upgraded from “good” to “very good” with the multi-site calibration technique. Simultaneously, the PBIAS at Hanwella and Kithulgala improved from “unsatisfactory” to “satisfactory” and “satisfactory” to “good” model performance, while the RSR improved from “good” to “very good” model performance at Deraniyagala, indicating the innovative multi-site calibration approach demonstrated a significant improvement in the results. Hence, this study will provide valuable insights for hydrological modelers to determine the most appropriate calibration strategy for their large-scale watersheds, considering the spatial variation of the watershed characteristics, thereby reducing the uncertainty in hydrologic predictions.
Authors
Sekhar Udaya NagothuAbstract
The final chapter in the book summarizes the key messages and recommendations from the disparate chapters. The chapter provides the challenges and at the same time an optimistic note about future climate actions citing some of the ongoing good initiatives. The possible technical, investment and policy options necessary for upscaling CNRFS are highlighted toward the end.
Authors
Shyamaranjan Das Mohapatra Najam Waris Zaidi Minati Mohapatra Sekhar Udaya Nagothu Radhakrushna Senapati Munmun Mohapatra Bhubananda Adhikari Subhendu Sekhar Pradhan Amaresh Kumar NayakAbstract
This chapter provides a comprehensive review of various integrated pest management (IPM) measures in combination with bio-based interventions, and physical and cultural practices that provide proven benefits for biodiversity, ecosystem services, and climate mitigation. The chapter illustrates the importance of digital technologies that represent another line of promising solutions to counter the environmental costs of crop production systems and enhance climate neutrality. Such solutions include precision farming with threshold-based and spatially targeted application of pesticides. A key factor to bridge gaps between scientific knowledge and practical implementation of IPM measures is the continuous involvement, training, and co-design of solutions with farmers’ communities and other stakeholders.
Abstract
Chapter 9 begins with a brief introduction followed by a conceptual framework showing the linkages and interactions between different institutional, market, and policy factors affecting adoption of climate-neutral and resilient farming systems in the agriculture sector. The chapter then discusses the barriers for adoption, which operate at various levels in the value chains (VCs). The role played by stakeholders (VC actors, farmers’ group, research, government agencies, and donors) in the farmers’ adoption and the dynamics and partnerships to be developed between different VC actors for upscaling CNRFS is analyzed. Experiences from case studies in Africa (Kenya and Rwanda) are shared, demonstrating how strategies to overcome weaknesses and adoption barriers in the selected value chain together with the support of multi-actor partnerships. Toward the end, some concluding remarks and policy recommendations for upscaling CNRFS are provided.
Abstract
The species composition of benthic algae changes as water phosphorus concentrations increase, and these changes can be used for ecological status assessment according to the Water Framework Directive. Natural background phosphorus concentrations in rivers and streams that are unaffected by anthropogenic impacts are usually low. Running waters draining catchments with deposits of marine clay, however, may have enhanced phosphorus concentrations, because the clay is naturally rich in apatite. Almost all clay rich areas have been cultivated for centuries, however, and fertilization has increased the soil phosphorus levels. It has, therefore, been difficult to disentangle natural from anthropogenically enhanced phosphorus in streams draining clay rich areas. We compared water phosphorus concentrations, and the Periphyton Index of Trophic Status PIT, between clay and non-clay, impacted and unimpacted rivers in Norway. We found that water phosphorus concentrations and the PIT index were higher in unimpacted clay rivers than in unimpacted non-clay rivers, indicating that natural phosphorus concentrations in clay rivers are indeed enhanced compared to rivers without deposits of marine clay. In addition, phosphate-P contributed 18–23% to total phosphorus in unimpacted clay rivers, but 33–37% in unimpacted and impacted non-clay rivers and clay rivers affected by agriculture. This indicates that the total phosphorus in unimpacted clay rivers is less bioavailable than in non-clay rivers and in impacted clay rivers. Water total phosphorus concentrations in unimpacted clay rivers significantly increased with catchment clay cover. Based on these findings, we derived new status class boundaries for the PIT index in clay rivers. Clay rivers are suggested to be assessed in only two status classes, i.e., “good or better” or “moderate or worse”, respectively. The good/moderate status class boundary for the PIT index was shown to increase with increasing catchment clay cover.