Svein Olav Krøgli

Research Scientist

(+47) 469 20 837
svein.olav.krogli@nibio.no

Place
Ås R9

Visiting address
Raveien 9, 1430 Ås

Abstract

When ground level photography is to be used in landscape monitoring, it is important to record when, where, how and possibly even why the photographs are taken. Standardisation enables better repeat photography in the future and maximises comparability of photos over time. We used a Cultural Environment protected by law on the peninsula of Bygdøy,Oslo municipality, as a study area to document advantages and disadvantages of different approaches to the first round of landscape photography for long-term monitoring.

Abstract

The decline in farmland birds observed throughout Europe during recent decades has attracted much attention. Agricultural intensification or land abandonment are commonly forwarded as key drivers. Several countries have established agri-environmental schemes (AES) to counter these negative trends among farmland birds. This paper reports a study of the relationship between land use and bird species in the agricultural landscape of Norway. The main objective was to investigate the effect of spatial heterogeneity and diversity of land use on total richness and abundance of farmland birds at a national level. Monitoring the distribution and abundance of birds is part of the Norwegian monitoring programme for agricultural landscapes. The monitoring programme is based on mapping of 1 × 1 km squares distributed across the entire agricultural landscape. Within these squares permanent observation points are established for bird monitoring. Detailed interpretation of aerial photographs provides the land classification. We tested the relationship between landscape metrics at different levels of land type detail and species richness and abundance of farmland and non-farmland birds. There was a positive relationship between species richness and abundance of farmland birds and agricultural area. For non-farmland birds the relationship was negative. Spatial heterogeneity of land use was a significant positive factor for both farmland and non-farmland species. High land type diversity was positive for farmland bird richness, but negative for abundance. Non-farmland bird richness was not affected by land type diversity, but abundance had a negative response. The results presented in this paper highlight the importance of a spatial heterogeneous landscape. However, we also found that land type diversity could negatively affect the abundance of both farmland and non-farmland birds. Our findings suggest a need for different management approaches depending on whether the aim is increased species richness or abundance. Achieving both aims with the same means might be difficult. We thus suggest a need for land use analyses before proper management strategies can be implemented.

To document

Abstract

Aim: Identify where bioeconomic development would best be located to maximise both local resources and the reusable waste from potentially collaborating sectors. We seek to answer the questions like Where are the best locations for bioeconomic clusters and how should this be assessed? What are the tradeoffs, how can they be mapped and described, and are there any general major obstacles? What are the conditions that would aid in developing a smart bioeconomy and what are the spatial implications of different developments?

Abstract

Part of the Vega archipelago in north-western Norway is a cultural landscape listed as a UNESCO World Heritage site. Its buffer zone comprises most of the main island of Vega, where agriculture is an important land use. The authors describe interdisciplinary research carried out in the buffer zone. The research revealed the significant role of agriculture for the maintenance of the traditional open coastal landscape. The finding was further underlined by the fact that many visitors to the site never reach the outer archipelago, which is the core of the listed site. Based on interpretations of aerial photographs, land cover maps were produced for three cross-sections in time (1965, 1986, and 2009). A further reclassification of the land cover was performed to capture the change in openness due to change in land cover. Viewshed maps of each building found on the aerial photographs were overlain with the openness classes to capture the visual consequences of the buildings due to changes in land cover. A marked decrease in open land surrounding the buildings was found in the study area, which comprised Holand and Floa-Kjul in Vega Municipality, which in turn comprises the islands of the Vega archipelago. The regrowth of the land seemed to be happening regardless of building category

Abstract

Background & Aim: Land-use regimes and their changes, as well as landscape heterogeneity are key determinants of the distribution and composition of species in cultural landscapes. In European agricultural landscapes, habitat loss due to both abandonment and intensification of agriculture fields are major causes for the decline of species diversity. Landscapes that are diverse in habitats and species are important to maintain basic ecosystem functions and services as, for instance, pollination or habitat preservation. In Norway, semi-natural species-rich habitats, such as agricultural grasslands, often occur in mosaics with forests and crop fields. This research studies key information for design of conservation plans focused on these habitats, addressing how landscape structure and land-use history affect the distribution, richness and composition of species in species-rich grasslands across geographical regions. Material & Methods: We recorded vegetation (species occurrence and cover) in agricultural grasslands with varying intensity and type of use from 569 plots of 8 x 8 m size systematically distributed throughout Norway (from 64 to 78 °N latitude). To identify the most important driving factors of species diversity and composition we explored the combined effects of historic and current land-use and the spatial landscape configuration of nearby land cover types (e.g. minimum distance to or area of neighbouring wetland, forest, cultivated land) taking into account the effects of grazing, elevation, and moisture conditions. Non-metrical multidimensional scaling (NMDS) was applied to identify the most important drivers of species composition. We used Generalized Additive Mixed Models to test the relationship of these drivers with patterns in species richness. Main results & Interpretations: NMDS revealed species composition to be explained most by the distance to surface cultivated land and transportation corridors (r=0.905, p<0.001 and r=-0.982, p<0.001; 1. NMDS axis) as well as shape of the patch in which the vegetation plot is embedded (patch shape) and grazing intensity (r=0.988, p<0.001 and r=-0.952, p<0.001; 2. NMDS axis). Observed patterns in species richness were statistically significantly linked to the combined effects of elevation, grazing intensity, historical land-use, patch shape, distance to transportation corridors and forest, and area of nearest wetland. Our results demonstrate the importance of a variety of factors influencing the species composition and richness in Norwegian grasslands. We found that both the landscape element harbouring the observed plot and also the surrounding landscape structure and intensity of land-use are important determinants of species diversity. The fact that distance to more intensively managed agricultural land is one of the strongest explanatory facts signals how effects of agricultural management practices reaches outside the field itself and into adjacent landscape elements. This suggests that the entire landscape needs to be taken into consideration when management of a particular habitat patch is planned.

To document

Abstract

The Ritland structure is a newly discovered impact structure, which is located in southwestern Norway. The structure is the remnant of a simple crater 2.5 km in diameter and 350 m deep, which was excavated in Precambrian gneissic rocks. The crater was filled by sediments in Cambrian times and covered by thrust nappes of the Caledonian orogen in the Silurian–Devonian. Several succeeding events of uplift, erosion, and finally the Pleistocene glaciations, disclosed this well-preserved structure. The erosion has exposed brecciated rocks of the original crater floor overlain by a thin layer of melt-bearing rocks and postimpact crater-filling breccias, sandstones, and shales. Quartz grains with planar deformation features occur frequently within the melt-bearing unit, confirming the impact origin of the structure. The good exposures of infilling sediments have allowed a detailed reconstruction of the original crater morphology and its infilling history based on geological field mapping.