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.
2025
Authors
Michael Bekken Dimitrios Pavlou Jingyi Huang Chase M. Straw Christopher J. Kucharik Douglas J. SoldatAbstract
Three water balance models were used to quantify water use efficiency on 71 golf courses in the United States. The golf courses were separated into five geographic regions. The United States Golf Association (USGA), Tipping‐Bucket (TB), and Agro‐IBIS (AG) water balance models were used to estimate golf course water requirements. Actual water use was divided by the water requirement from each model to generate three water efficiency scores for each golf course (WES USGA , WES TB , and WES AG ). The mean WES USGA was 1.16, the mean WES TB was 1.25, and the mean WES AG was 1.17. Thus, golf courses in this study used between 16% and 25% more water than predicted by the three models. The coefficients of variation of WES USGA , WES TB , and WES AG were all 0.45 or higher, indicating that some golf courses used significantly more or less water than predicted by the models. Rooting depth, irrigated area, and soil texture were especially important modeling parameters for the golf course water requirement calculations. While onsite evaluation should still be carried out to verify the assumptions made by the water balance models, the models are promising tools to quickly identify golf course superintendents who are likely to be using water efficiently and those who could use less.
Authors
Michael Bekken Gregg Sanford Douglas J. SoldatAbstract
The goal of this study was to begin developing a methodology with which individual golf courses can measure their soil organic carbon (SOC) stocks and sequestration. We propose a two‐tiered methodology that starts with the space‐for‐time substitution method but then graduates to the longitudinal method. Space‐for‐time allows golf courses to compare their SOC stock to the SOC stock of the surrounding land use, whereas the longitudinal method provides a high‐resolution carbon sequestration estimate after 5 years. The first tier of this methodology was tested on two golf courses that are part of the same golf facility in the United Kingdom. The two golf courses and the agricultural fields adjacent to them, which also represented the historical land use of the golf courses, were sampled to determine their SOC stocks. We recognize that the SOC stock trajectories of the golf courses and neighboring crop fields are unknown, and thus we do not use the term carbon sequestration to describe the differences in carbon stocks between the two land uses. Instead, we use the term counterfactual carbon storage to describe that the SOC stock of the surrounding agricultural fields was the best available representation of what the SOC stock of the land the golf courses are now on would have been had the golf courses not been built. We found the golf courses had higher SOC stocks than the surrounding agricultural fields, which corresponded to 0.41 and 0.77 Mg C ha −1 year −1 more carbon in the soils of the golf courses than on the surrounding agricultural fields. Maintenance emissions from the time of construction to the present were also estimated to calculate the lifecycle net climate impact of the golf courses. Our results highlight the importance of emissions reductions if golf courses are to be carbon neutral throughout their lifecycle.
Abstract
As summer droughts become more common and water resources more precious, some golf courses in Scandinavia are turning to lower quality irrigation water to irrigate their courses. We visited seven golf courses on the Baltic coast of Sweden using lower quality irrigation water to interview superintendents and to take soil and water samples for salinity analysis. Four of the seven golf courses experience salinity stress regularly, primarily in a 6–8 week period in July and August. Soil and water samples taken at the seven golf courses in October 2024 generally did not exceed salinity thresholds for cool‐season turfgrasses, but retesting of water and soil will be conducted again in 2025 with at least one of the sampling events conducted during the summer period in which salinity stress symptoms usually occur.
Authors
Martha Kandziora Christian Brochmann Abel Gizaw Seid A Lovisa S Gustafsson Desalegn Chala GeleteAbstract
No abstract has been registered
Authors
Martha Kandziora Diana L. A. Vásquez Christian Brochmann Abel Gizaw Seid A Lovisa S Gustafsson Desalegn Chala Gelete Mercè Galbany‐Casals Filip Kolář Petr Sklenář Nicolai M. Nürk Roswitha SchmicklAbstract
Aim Species coexistence is based on resource partitioning and modulates biodiversity patterns across climates, latitudes and altitudes. Resource partitioning can occur via niche size or separation in the geographic range or ecological niche. While resource partitioning promotes biodiversity, the impact of different partitioning strategies on species richness remains largely unexplored. Location Two ecosystems with similar climates and ages are the species‐rich tropical alpine ecosystem in the South American Andes and the more species‐poor tropical alpine ecosystem in the eastern African mountains. Time Period Present‐day distribution and climatic conditions, integrating phylogenetic information extending back to the last 7 million years maximum. Major Taxa Studied Six lineages from the Asterales; three in each ecosystem, respectively. Methods We test whether geographic range and climatic niche partitioning strategies may explain differences in species richness between two ecosystems. We combine phylogenomic data with occurrence records and estimate metrics of size and overlap for climatic niche and geographic range. Results We show that the Andean species have larger climatic niches than the African species, suggesting that niche size is not explaining higher species richness in the Andes. Instead, a striking pattern for species with overlapping geographic ranges emerged: the Andean species show less climatic niche overlap than the African species, indicating more effective niche separation among Andean species. Main Conclusions We hypothesise that differences in resource partitioning, specifically increased niche separation among geographically overlapping species in the Andes compared to the eastern African mountains, contribute to the species richness difference between these tropical alpine biodiversity hotspots.
Authors
Eirik Gottschalk BalloAbstract
One of the key challenges we face today is the changing climate and its environmental impacts, affecting all life on Earth. Examining historical human responses to climate crises provides insights into resilience and adaptability. Robust data is essential for studying past climate and environmental changes effectively. European climate records covering the past 2000 years reveal a prolonged cooling period, known as the Dark Ages Cooling Period (c. 300–800 CE), punctuated by a pronounced cooling in the mid-6th century. Studies show that these cold intervals are more complex and regionally varied than previously believed. In the 6th century in Norway, archaeological evidence points to crop failures, famine, farm abandonment and changes in social organization in some regions, while others experienced minimal impact during these cold periods. However, southeastern Norway lacks detailed high-resolution paleoclimate and paleoenvironmental reconstructions, limiting our ability to fully understand these events. This thesis aims to enhance understanding of climate, environmental, and societal dynamics in southeastern Norway over the past 2000 years, focusing on the Dark Ages Cold Period (c. 300–800 CE), through sediment analysis from Lake Sagtjernet and Lake Ljøgottjern in southeastern Norway. We introduce a μCT scan method for varve counting for Lake Sagtjernet, establishing the first varve chronology from a Norwegian lake, covering c. 4023 years. This chronology enables the first paleoclimate and paleoenvironmental reconstruction from Norwegian varved lake sediments. This reconstruction reveals 2000 years of temperature variability, highlighting a major cooling event—the largest in 2000 years—that aligns with the 6th century cooling event. However, sparse settlements in the first millennium complicate climate impact interpretation at Lake Sagtjernet, while the last millennium shows increased human activities during both warm and cold periods. Reconstructed temperatures between 200 and 1300 CE from Lake Ljøgottjern indicate a notably colder period from 300 to 800 CE, compared to the periods before (200–300 CE) and after (800–1300 CE), identified as the Dark Ages Cold Period. Temperature fluctuations within this cold period significantly influenced agricultural strategies at the more populated Lake Ljøgottjern. Warmer intervals favoring crop cultivation and colder intervals prompting a shift towards livestock farming, illustrating the impact of climatic conditions on societal development.
Authors
Karin Juul Hesselsøe Anne Friederike Borchert Trond Olav Pettersen Kristoffer Herland Hellton Trygve S. AamlidAbstract
Ice encasement (IE) is one of the big challenges in winter stress management on golf course putting greens in Northern Scandinavia. The turfgrass is damaged due to lack of oxygen (hypoxia or anoxia) and accumulation of toxic by‐products of anaerobic respiration. Breeding IE‐tolerant turfgrass species and varieties is the best defense against these challenges. A method to simulate ice encasement was tested to screen selected varieties of winter‐hardy bentgrass species and red fescue subspecies. Note that 32 varieties were chosen from the SCANGREEN trial seeded at NIBIO Landvik, Norway, in 2019. Samples were taken in December 2020, 2021, and 2022, vacuum sealed in plastic, and stored in darkness at 0.5°C for up to 77 days to test them for their tolerance to simulated ice encasement (SIE). Samples were incubated at different intervals; plants were potted, and tiller survival was tested after 4 weeks of regrowth. Lethal duration of ice encasement (LD 50 ) that is, the number of days under anoxia that kills 50% of the plant population for each species and variety was calculated. The results showed that the ranking of cool season turfgrass species for tolerance to SIE was velvet bentgrass > Chewings fescue > slender creeping red fescue = colonial bentgrass > creeping bentgrass. This ranking does not fully reflect the ranking found in field tests where velvet bentgrass was superior together with creeping bentgrass. SIE caused a more rapid development of anoxia than IE in the field, and we hypothesize that creeping bentgrass is less tolerant to these conditions compared to the other species tested. To make the SIE method more representative for IE in field, it should be further adapted with incubation at lower temperatures, and with acclimation conditions to be standardized prior to sampling. Within species, the best tolerance to IE was found in velvet bentgrass Nordlys, creeping bentgrass Penncross, Chewings fescue Lykke, and slender creeping red fescue Cezanne.
Abstract
The primary benefits of turfgrass sod include rapid greenery and soil coverage, but its production causes concerns about soil losses at production sites. Soil adheres to the grass root system during harvesting and is removed from the sod farm, which in the long run might lead to soil degradation on the sod farm. In this study, we investigated sod thickness and the removal of organic and mineral matter when harvesting 24 fields representing 12 Norwegian sod farms in 2022 and 2023. On each field, 10 sod strips were randomly chosen, and five sod plugs were collected from each strip. Sod thickness was measured using a sliding gauge. Sod mineral matter (SMM: soil and thatch mineral matter) and sod organic matter (SOM: soil and thatch organic matter) contents were quantified by loss on ignition at 550°C. Management and field properties were also documented. Results showed an average amount of mineral matter in the sod strips of 36 Mg ha −1 for all fields but with significant variation among fields ( p < 0.001). The average SOM content was 10 Mg ha −1 . Mean sod thickness was 15.4 mm and had a strong correlation with SOM ( r = 0.8) but only a moderate correlation with SMM ( r = 0.6). Soil water content and surface hardness at harvest affected sod thickness and SMM only slightly. Sod harvesters with twin heads harvested significantly thicker sod strips and removed more mineral matter than harvesters with single cutting heads. Soil texture did not have a significant impact on sod thickness or mineral matter removal.
Authors
Siv Mari AurdalAbstract
This paper is a historical review of scientific progress on horticultural growing media, with particular attention to the role of peat and the recurring search for sustainable alternatives. It is well established that peat became the cornerstone of horticultural growing media because it offered a unique combination of nutrient control, pH buffering, water retention, absence of harmful microorganisms, and structural stability. Equally evident are the environmental concerns and sustainability goals that have driven the search for alternative materials since the 1980s. This historical review traces the evolution of growing media from the early 20th century to the mid-2020s, focusing on how peat came to dominate and why its substitution has proven so difficult. Drawing on a wide range of literature, including peer-reviewed experimental studies, historical sources, symposia proceedings, institutional reports, and synthesis articles, the historical development of growing media science and practice across each decade is outlined. Attention is given to various composts, coir, wood fiber, bark, and biochar and challenges with these materials related to product standardization for end-user reliability. While many alternatives show potential, particularly as partial components or as stand-alone media under certain conditions, no single material currently offers a fully viable replacement for peat. Instead, the most promising direction appears to be peat-reduced mixtures optimized for both functionality and sustainability. By understanding how growing media science has evolved and where it has struggled, this paper identifies lessons critical to navigating the ongoing transition toward more sustainable and functional systems.
Authors
Abel Gizaw Seid Dimitar Dimitrov Catherine Aloyce Masao Felly Mugizi Tusiime Tigist Woldimu Ahmed Abdikadir Abdi Desalegn Chala Galina Gusarova Virginia Mirré Mulugeta Kebede Rosalia Pineiro Mary Namaganda Pilar Catalan Manuel Pimentel Pereira Pierre Robert Michel Taberlet Hans Peter Linder Magnus Popp Gerald Eilu Pantaleo Munishi Geoffrey Mwachala Sileshi Nemomissa Christian BrochmannAbstract
Aim It has been proposed that species diversity (SD) and genetic diversity (GD) co-vary across natural communities because both are shaped by processes such as immigration and drift. However, empirical reports are contradictory, and multispecies studies are rare. Here we test the hypothesis that the two diversity measures do not correlate in systems with high levels of immigration stochasticity and little GD caused by strong genetic drift. Location Tropical alpine habitats on six of the highest mountains in eastern Africa. Taxon Vascular plants. Methods We sampled 375 taxa in 75 plots in five habitat types, recorded ecological variables, and genotyped 1793 plants representing 20 species/species complexes. Results We confirmed that intrapopulation GD was exceptionally low in this system and found that most Species-Genetic Diversity Correlations (SGDCs) were weak and insignificant. Whereas SD was correlated with several environmental variables, GD was only correlated with mountain identity (geographical location) and mountain age. Main Conclusions Our findings support the hypothesis that SGDCs are lacking in habitat island systems such as the tropical alpine region in Africa, which is characterised by frequent population size fluctuations, extinctions, and colonisations via long-distance dispersal (LDD) during the glacial cycles. The stochastic nature of LDD combined with strong genetic drift and founder effects is likely to cause low GD and lack of SGDCs, implying that SD cannot be used as a proxy for GD in conservation management of such systems.