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.
2021
Authors
Matthew J. Kauffman Francesca Cagnacci Simon Chamaillé-Jammes Mark Hebblewhite J. Grant C. Hopcraft Jerod A. Merkle Thomas Mueller Atle Mysterud Wibke Erika Brigitta Peters Christiane Roettger Alethea Steingisser James E. Meacham Kasahun Abera Jan Adamczewski Ellen O. Aikens Hattie Bartlam-Brooks Emily Bennitt Joel Berger Charlotte Boyd Steeve D. Côté Lucie Isabelle Debeffe Andrea S. Dekrout Nandintsetseg Dejid Emiliano Donadio Luthando Dziba William F. Fagan Claude Fischer Stefano Focardi John M. Fryxell Richard W. S. Fynn Chris Geremia Benito A. González Anne Gunn Elie Gurarie Marco Dietmar Heurich Jodi Hilty Mark A. Hurley Aran Johnson Kyle Joly Petra Kaczensky Corinne J. Kendall Pavel Kochkarev Leonid Kolpaschikov Rafal Kowalczyk Frank van Langevelde Binbin V. Li Anne Loison Alex L. Lobora Tinaapi H. Madiri David Mallon Erling Meisingset Christer Moe Rolandsen Erling Johan Solberg Olav StrandAbstract
Migration of ungulates (hooved mammals) is a fundamental ecological process that promotes abundant herds, whose effects cascade up and down terrestrial food webs. Migratory ungulates provide the prey base that maintains large carnivore and scavenger populations and underpins terrestrial biodiversity (fig. S1). When ungulates move in large aggregations, their hooves, feces, and urine create conditions that facilitate distinct biotic communities. The migrations of ungulates have sustained humans for thousands of years, forming tight cultural links among Indigenous people and local communities. Yet ungulate migrations are disappearing at an alarming rate (1). Efforts by wildlife managers and conservationists are thwarted by a singular challenge: Most ungulate migrations have never been mapped in sufficient detail to guide effective conservation. Without a strategic and collaborative effort, many of the world’s great migrations will continue to be truncated, severed, or lost in the coming decades. Fortunately, a combination of animal tracking datasets, historical records, and local and Indigenous knowledge can form the basis for a global atlas of migrations, designed to support conservation action and policy at local, national, and international levels.
Lecture – Moose in Finnmark 2.0 – Space use and management in a changing landscape
Erling Meisingset
Authors
Erling MeisingsetAbstract
No abstract has been registered
Abstract
Proximal sensing technologies are becoming widely used across a range of applications in environmental sciences. One of these applications is in the measurement of the ground surface in describing soil displacement impacts from wheeled and tracked machinery in the forest. Within a period of 2–3 years, the use photogrammetry, LiDAR, ultrasound and time-of-flight imaging based methods have been demonstrated in both experimental and operational settings. This review provides insight into the aims, sampling design, data capture and processing, and outcomes of papers dealing specifically with proximal sensing of soil displacement resulting from timber harvesting. The work reviewed includes examples of sensors mounted on tripods and rigs, on personal platforms including handheld and backpack mounted, on mobile platforms constituted by forwarders and skidders, as well as on unmanned aerial vehicles (UAVs). The review further highlights and discusses the benefits, challenges, and some of the shortcomings of the various technologies and their application as interpreted by the authors. The majority of the work reviewed reflects pioneering approaches and innovative applications of the technologies. The studies have been carried out almost simultaneously, building on little or no common experience, and the evolution of standardized methods is not yet fully apparent. Some of the issues that will likely need to be addressed in developing this field are (i) the tendency toward generating apparently excessively high resolution micro-topography models without demonstrating the need for or contribution of such resolutions on accuracy, (ii) the inadequacy of conventional manual measurements in verifying the accuracy of these methods at such high resolutions, and (iii) the lack of a common protocol for planning, carrying out, and reporting this type of study.
Abstract
No abstract has been registered
Authors
Rasmus AstrupAbstract
No abstract has been registered
Authors
Marian Schönauer Kari Väätäinen Robert Prinz Harri Lindeman Dariusz Pszenny Martin Jansen Joachim Maack Bruce Talbot Rasmus Astrup Dirk JaegerAbstract
The utilization of detailed digital terrain models entails an enhanced basis for supporting sustainable forest management, including the reduction of soil impacts through predictions of site trafficability during mechanized harvesting operations. Since wet soils are prone to traffic-induced damages, soil moisture is incorporated into several systems for spatial predictions of trafficability. Yet, only few systems consider temporal dynamics of soil moisture, impeding the accuracy and practical value of predictions. The depth-to-water (DTW) algorithm calculates a cartographic index which indicates wet areas. Temporal dynamics of soil moisture are simulated by different DTW map-scenarios derived from set flow initiation areas (FIA). However, the concept of simulating seasonal moisture conditions by DTW map-scenarios was not analyzed so far. Therefore, we conducted field campaigns at six study sites across Europe, capturing time-series of soil moisture and soil strength along several transects which crossed predicted wet areas. Assuming overall dry conditions (FIA = 4.00 ha), DTW predicted 20% of measuring points to be wet. When a FIA of 1.00 ha (moist conditions) or 0.25 ha (wet conditions) were applied, DTW predicted 29% or 58% of points to be wet, respectively. De facto, 82% of moisture measurements were predicted correctly by the map-scenario for overall dry conditions – with 44% of wet measurements deviating from predictions made. The prediction of soil strength was less successful, with 66% of low values occurring on areas where DTW indicated dryer soils and subsequently a sufficient trafficability. The condition-specific usage of different map-scenarios did not improve the accuracy of predictions, as compared to static map-scenarios, chosen for each site. We assume that site-specific and non-linear hydrological processes compromise the generalized assumptions of simulating overall moisture conditions by different FIA.
Abstract
Long-term machine-derived data sets comprising 140,000 trees were collected from four harvesters of equal age and similar working conditions, into two machine size classes, viz. two Ponsse Bears and two smaller Ponsse Beavers. Productivity functions for each size class were modelled using a nonlinear mixed effects approach. Based on these functions, unit costs and their sensitivity to utilization rates and cost of capital were assessed. Results showed that despite considerably higher capital costs (32%) on the Bear, a 50% higher mean productivity resulted in a unit cost only 17% higher than the Beaver in a disadvantageous scenario (high interest rates and low utilisation), and a 6% lower unit cost than the Beaver in an advantageous scenario (low interest and high utilisation), within the range of tree sizes observed. Between these extremes, only marginal differences in unit costs were observed. This demonstrates that the difference in ownership and operating costs between larger and smaller harvesters is largely negated by the difference in productivity rates. These results can provide useful insight into timber harvester investment decisions. Harvesters from two adjacent size classes can be used interchangeably at the same unit cost within a wide range of tree sizes despite productivity differences. It should be noted that increased repair costs and an eventual reduction in expected economic lifetime on a smaller harvester, or the negative effects of using a larger harvester in smaller trees, e.g. thinning operations, were not taken into account in this work.
Authors
Inger Sundheim FløistadAbstract
No abstract has been registered
Authors
Ricardo Ruiz-Peinado Hans Pretzsch Magnus Löf Michael Heym Kamil Bielak Jorge Aldea Ignacio Barbeito Gediminas Brazaitis Lars Drössler Kšištof Godvod Aksel Granhus Stig-Olof Holm Aris Jansons Ekaterina Makrickienė Marek Metslaid Sandra Metslaid Arne Nothdurft Ditlev Otto Juel Reventlow Roman Sitko Gintarė Stankevičienė Miren del RíoAbstract
Mixed-species stands have been found to be more productive than would be expected from the performance of their component species in monocultures due to facilitation and complementarity between species, although these interactions depend on the combination of species present. Our study focuses on monospecific and mixed-species stands of Scots pine and Norway spruce using 20 triplets established in nine countries along a climatic gradient across Europe. Differences in mean tree and stand characteristics, productivity and stand structure were assessed. Basal area increment in mixed stands was 8% higher than expected while volume increment was only 2% greater. Scots pine trees growing in mixed-species stands showed 11% larger quadratic mean diameter, 7% larger dominant diameter, 17% higher basal area and 25% higher stand volume than trees growing in monospecific stands. Norway spruce showed only a non-significant tendency to lower mean values of diameters, heights, basal area, as well standing volume in mixtures than monocultures. Stand structure indices differed between mixed stands and monocultures of Scots pine showing a greater stratification in mixed-species stands. Furthermore, the studied morphological traits showed little variability for trees growing in monospecific stands, except for diameter at breast height, crown length and crown length ratio. For trees growing in mixed stands, all the morphological traits of the trees were identified as different. Some of these morphological traits were associated with relative productivity. Nevertheless, relative productivity in mixed-species stands was not related to site conditions.
Authors
Jorge Aldea Ricardo Ruiz-Peinado Miren del Río Hans Pretzsch Michael Heym Gediminas Brazaitis Aris Jansons Marek Metslaid Ignacio Barbeito Kamil Bielak Aksel Granhus Stig-Olof Holm Arne Nothdurft Roman Sitko Magnus LöfAbstract
Mixed forests are suggested as a strategic adaptation of forest management to climate change. Scots pine (Pinus sylvestris L.) and Norway spruce (Picea abies (L.) Karst.) are tree species of high economic and ecological value for European forestry. Both species coexist naturally in a large part of their distributions but there is a lack of knowledge on the ecological functioning of mixtures of these species and how to manage such stands. This paper analyses these species' intra-and inter-specific competition, including size-symmetric vs. size-asymmetric competition, and explore the effect of weather conditions on tree growth and competition. We studied basal area growth at tree level for Scots pine and Norway spruce in mixed versus pure stands in 22 triplets of fully-stocked plots along a broad range of ecological conditions across Europe. Stand inventory and increment cores provided insights into how species mixing modifies tree growth compared with neighbouring pure stands. Five different competition indices, weather variables and their interactions were included and checked in basal area growth models using a linear mixed model approach. Interspecific size-asymmetric competition strongly influenced growth for both tree species, and was modulated by weather conditions. However, species height stratification in mixed stands resulted in a greater tree basal area growth of Scots pine (10.5 cm 2 year − 1) than in pure stands (9.3 cm 2 year − 1), as this species occupies the upper canopy layer. Scots pine growth depended on temperature and drought, whereas Norway spruce growth was influenced only by drought. Interspecific site-asymmetric competition increased in cold winters for Scots pine, and decreased after a drought year for Nor-way spruce. Although mixtures of these species may reduce tree size for Norway spruce, our results suggest that this could be offset by faster growth in Scots pine. How inter-specific competition and weather conditions alter tree growth may have strong implications for the management of Scots pine-Norway spruce mixtures along the rotation period into the ongoing climate change scenario.