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.
2023
Authors
Sofia Junttila Jonas Ardö Zhanzhang Cai Hongxiao Jin Natascha Kljun Leif Klemedtsson Alisa Krasnova Holger Lange Anders Lindroth Meelis Mölder Steffen M. Noe Torbern Tagesson Patrik Vestin Per Weslien Lars EklundhAbstract
Northern forest ecosystems make up an important part of the global carbon cycle. Hence, monitoring local-scale gross primary production (GPP) of Northern forest is essential for understanding climatic change impacts on terrestrial carbon sequestration and for assessing and planning management practices. Here we evaluate and compare four methods for estimating GPP using Sentinel-2 data in order to improve current available GPP estimates: four empirical regression models based on either the 2-band Enhanced Vegetation Index (EVI2) or the plant phenology index (PPI), an asymptotic light response function (LRF) model, and a light-use efficiency (LUE) model using the MOD1732 algorithm. These approaches were based on remote sensing vegetation indices, air temperature (Tair), vapor pressure deficit (VPD), and photosynthetically active radiation (PAR). The models were parametrized and evaluated using in-situ data from eleven forest sites in North Europe, covering two common forest types, evergreen needleleaf forest and deciduous broadleaf forest. Most of the models gave good agreement with eddy covariance-derived GPP. The VI-based regression models performed well in evergreen needleleaf forest (R2 = 0.69–0.78, RMSE = 1.97–2.28 g C m−2 d−1, and NRMSE =9-11.0%, eight sites), whereas the LRF and MOD17 performed slightly worse (R2 = 0.65 and 0.57, RMSE = 2.49 and 2.72 g C m−2 d−1, NRMSE = 12 and 13.0%, respectively). In deciduous broadleaf forest all models, except the LRF, showed close agreements with the observed GPP (R2 = 0.75–0.80, RMSE = 2.23–2.46 g C m−2 d−1, NRMSE = 11–12%, three sites). For the LRF model, R2 = 0.57, RMSE = 3.21 g C m−2 d−1, NRMSE = 16%. The results highlighted the necessity of improved models in evergreen needleleaf forest where the LUE approach gave poorer results., The simplest regression model using only PPI performed well beside more complex models, suggesting PPI to be a process indicator directly linked with GPP. All models were able to capture the seasonal dynamics of GPP well, but underestimation of the growing season peaks were a common issue. The LRF was the only model tending to overestimate GPP. Estimation of interannual variability in cumulative GPP was less accurate than the single-year models and will need further development. In general, all models performed well on local scale and demonstrated their feasibility for upscaling GPP in northern forest ecosystems using Sentinel-2 data.
Abstract
No abstract has been registered
Authors
Madelen Cecilia Espino Fjeld Atle Mysterud Inger Maren Rivrud Erling Meisingset Tilde K. S. HjermannAbstract
No abstract has been registered
Abstract
To reduce the dependency of fungicides in treating turf grass diseases we investigated the use of biostimulants and colour pigments and their capacity to prevent the proliferation of microdochium and anthracnose on annual meadow grass (Poa annua). The study was conducted in two sites (Landvik, Norway and Bingley, United Kingdom) for two years (May 2020 – May 2022). The biostimulant Hicure could reduce the fungicidal use from three to two without loss of efficiency in treating the fungal diseases. The biostimulant also preserved the visual quality of the turf grasses when reducing the fungicidal treatment from three to two. The colour pigment Ryder in all treatments was effective at increasing the colour intensity of the turf grasses compared to the control. Additionally, the biostimulant treatments could treat anthracnose better than the fungicidal only treatment. The biostimulant Hicure and the colour pigment Ryder have potential for further research and development to reduce the use of fungicides while simultaneously preserving the pristine quality of turf grasses in golf greens.
Authors
Lars T. HavstadAbstract
No abstract has been registered
Authors
Chathura Palliyaguru Vindhya Basnayake Randika K. Makumbura Miyuru Gunathilake Nitin Muttil Eranga M. Wimalasiri Upaka RathnayakeAbstract
Soil degradation is a serious environmental issue in many regions of the world, and Sri Lanka is not an exception. Maha Oya River Basin (MORB) is one of the major river basins in tropical Sri Lanka, which suffers from regular soil erosion and degradation. The current study was designed to estimate the soil erosion associated with land use changes of the MORB. The Revised Universal Soil Loss Equation (RUSLE) was used in calculating the annual soil erosion rates, while the Geographic Information System (GIS) was used in mapping the spatial variations of the soil erosion hazard over a 30-year period. Thereafter, soil erosion hotspots in the MORB were also identified. The results of this study revealed that the mean average soil loss from the MORB has substantially increased from 2.81 t ha−1 yr−1 in 1989 to 3.21 t ha−1 yr−1 in 2021, which is an increment of about 14.23%. An extremely critical soil erosion-prone locations (average annual soil loss > 60 t ha−1 yr−1) map of the MORB was developed for the year 2021. The severity classes revealed that approximately 4.61% and 6.11% of the study area were in high to extremely high erosion hazard classes in 1989 and 2021, respectively. Based on the results, it was found that the extreme soil erosion occurs when forests and vegetation land are converted into agricultural and bare land/farmland. The spatial analysis further reveals that erosion-prone soil types, steep slope areas, and reduced forest/vegetation cover in hilly mountain areas contributed to the high soil erosion risk (16.56 to 91.01 t ha−1 yr−1) of the MORB. These high soil erosional areas should be prioritized according to the severity classes, and appropriate land use/land cover (LU/LC) management and water conservation practices should be implemented as recommended by this study to restore degraded lands.
Authors
Lars T. HavstadAbstract
No abstract has been registered
Authors
Iris Hordijk Daniel S. Maynard Simon P. Hart Mo Lidong Hans ter Steege Jingjing Liang Sergio de-Miguel Gert-Jan Nabuurs Peter B. Reich Meinrad Abegg C. Yves Adou Yao Giorgio Alberti Angelica M. Almeyda Zambrano Braulio V. Alvarado Alvarez-Davila Esteban Patricia Alvarez-Loayza Luciana F. Alves Christian Ammer Clara Antón Fernández Alejandro Araujo-Murakami Luzmila Arroyo Valerio Avitabile Gerardo A. Aymard C Timothy Baker Radomir Bałazy Olaf Banki Jorcely Barroso Meredith L. Bastian Jean-Francois Bastin Luca Birigazzi Philippe Birnbaum Robert Bitariho Pascal Boeckx Frans Bongers Olivier Bouriaud Pedro H. S. Brancalion Susanne Brandl Roel Brienen Eben N. Broadbent Helge Bruelheide Filippo Bussotti Roberto Cazzolla Gatti Ricardo G. César Goran Cesljar Robin Chazdon Han Y. H. Chen Chelsea Chisholm Emil Cienciala Connie J. Clark David B. Clark Gabriel Colletta David Coomes Fernando Cornejo Valverde Jose J. Corral-Rivas Philip Crim Jonathan Cumming Selvadurai Dayanandan André L. de Gasper Mathieu Decuyper Géraldine Derroire Ben DeVries Ilija Djordjevic Amaral Iêda Aurélie Dourdain Engone Obiang Nestor Laurier Brian Enquist Teresa Eyre Adandé Belarmain Fandohan Tom M. Fayle Leandro V. Ferreira Ted R. Feldpausch Leena Finér Markus Fischer Christine Fletcher Lorenzo Frizzera Javier G. P. Gamarra Damiano Gianelle Henry B. Glick David Harris Andrew Hector Andreas Hemp Geerten Hengeveld Bruno Hérault John Herbohn Annika Hillers Eurídice N. Honorio Coronado Cang Hui Hyunkook Cho Thomas Ibanez Il Bin Jung Nobuo Imai Andrzej M. Jagodzinski Bogdan Jaroszewicz Vivian Johanssen Carlos A. Joly Tommaso Jucker Viktor Karminov Kuswata Kartawinata Elizabeth Kearsley David Kenfack Deborah Kennard Sebastian Kepfer-Rojas Gunnar Keppel Mohammed Latif Khan Timothy Killeen Hyun Seok Kim Kanehiro Kitayama Michael Köhl Henn Korjus Florian Kraxner Diana Laarmann Mait Lang Simon Lewis Huicui Lu Natalia Lukina Brian Maitner Yadvinder Malhi Eric Marcon Beatriz Schwantes Marimon Ben Hur Marimon-Junior Andrew Robert Marshall Emanuel Martin Olga Martynenko Jorge A. Meave Omar Melo-Cruz Casimiro Mendoza Cory Merow Stanislaw Miscicki Abel Monteagudo Mendoza Vanessa Moreno Sharif A. Mukul Philip Mundhenk Maria G. Nava-Miranda David Neill Victor Neldner Radovan Nevenic Michael Ngugi Pascal A. Niklaus Jacek Oleksyn Petr Ontikov Edgar Ortiz-Malavasi Yude Pan Alain Paquette Alexander Parada-Gutierrez Elena Parfenova Minjee Park Marc Parren Narayanaswamy Parthasarathy Pablo L. Peri Sebastian Pfautsch Oliver L. Phillips Nicolas Picard Maria Teresa Piedade Daniel Piotto Nigel C. A. Pitman Irina Polo Lourens Poorter Axel Dalberg Poulsen John R. Poulsen Hans Pretzsch Freddy Ramirez Arevalo Zorayda Restrepo-Correa Mirco Rodeghiero Samir Rolim Anand Roopsind Francesco Rovero Ervan Rutishauser Purabi Saikia Christian Salas-Eljatib Peter Schall Dmitry Schepaschenko Michael Scherer-Lorenzen Bernhard Schmid Jochen Schöngart Eric B. Searle Vladimír Šebeň Josep M. Serra-Diaz Douglas Sheil Anatoly Shvidenko Javier Silva-Espejo Marcos Silveira James Singh Plinio Sist Ferry Slik Bonaventure Sonké Alexandre F. Souza Krzysztof Stereńczak Jens-Christian Svenning Miroslav Svoboda Ben Swanepoel Natalia Targhetta Nadja Tchebakova Raquel Thomas Elena Tikhonova Peter Umunay Vladimir Usoltsev Renato Valencia Fernando Valladares Fons van der Plas Do Van Tran Michael E. Van Nuland Rodolfo Vasquez Martinez Hans Verbeeck Helder Viana Alexander C. Vibrans Simone Vieira Klaus von Gadow Hua-Feng Wang James Watson Gijsbert D. A. Werner Susan K. Wiser Florian Wittmann Verginia Wortel Roderick Zagt Tomasz Zawila-Niedzwiecki Chunyu Zhang Xiuhai Zhao Mo Zhou Zhi-Xin Zhu Irie Casimir Zo-Bi Thomas W. CrowtherAbstract
1. Biodiversity is an important component of natural ecosystems, with higher species richness often correlating with an increase in ecosystem productivity. Yet, this relationship varies substantially across environments, typically becoming less pronounced at high levels of species richness. However, species richness alone cannot reflect all important properties of a community, including community evenness, which may mediate the relationship between biodiversity and productivity. If the evenness of a community correlates negatively with richness across forests globally, then a greater number of species may not always increase overall diversity and productivity of the system. Theoretical work and local empirical studies have shown that the effect of evenness on ecosystem functioning may be especially strong at high richness levels, yet the consistency of this remains untested at a global scale. 2. Here, we used a dataset of forests from across the globe, which includes composition, biomass accumulation and net primary productivity, to explore whether productivity correlates with community evenness and richness in a way that evenness appears to buffer the effect of richness. Specifically, we evaluated whether low levels of evenness in speciose communities correlate with the attenuation of the richness–productivity relationship. 3. We found that tree species richness and evenness are negatively correlated across forests globally, with highly speciose forests typically comprising a few dominant and many rare species. Furthermore, we found that the correlation between diversity and productivity changes with evenness: at low richness, uneven communities are more productive, while at high richness, even communities are more productive. 4. Synthesis. Collectively, these results demonstrate that evenness is an integral component of the relationship between biodiversity and productivity, and that the attenuating effect of richness on forest productivity might be partly explained by low evenness in speciose communities. Productivity generally increases with species richness, until reduced evenness limits the overall increases in community diversity. Our research suggests that evenness is a fundamental component of biodiversity–ecosystem function relationships, and is of critical importance for guiding conservation and sustainable ecosystem management decisions.
Authors
Aksel GranhusAbstract
No abstract has been registered
Authors
Johannes BreidenbachAbstract
No abstract has been registered