| 1. |
- Cousins, Sara A. O., et al.
(författare)
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Reconstructing past land use and vegetation patterns using palaeogeographical and archaeological data : A focus on grasslands in Nynas by the Baltic Sea in south-eastern Sweden
- 2002
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Ingår i: Landscape and Urban Planning. - 0169-2046 .- 1872-6062. ; 61:1, s. 1-18
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Tidskriftsartikel (refereegranskat)abstract
- Past landscape characteristics were reconstructed in Nynas, south-eastern Sweden, using geographical and archaeological data together with pollen stratigraphy and an existing shore displacement model, with the aim to explore the development of semi-natural grasslands in the area. A 2.3 m peat core was analysed and radiocarbon dated at three levels. The pollen stratigraphy was estimated to start at approximately 3800 C-14 years before present (BP), at the end of Late Neolithic. Human activities are evident, from both archaeological findings and pollen analysis, for more than 4000 years. Grazing is apparent, possibly more intense around 3200 C-14 years BP, 2500-2600 C-14 years BP, 2100-2200 C-14 years BP, and 1300/1400 C-14 years BP to present day. From 1900+/-80 C-14 years BP and onwards cultivation is intensified at the same time as spruce (Picea abies) expands. Maps on land-cover distribution in the late 17th century was used as a model for the utilisation of the landscape during the Iron Age. Land-covers on very thin soils were grazed and sometimes mown within the village boundaries, but they were also used for cultivation in narrow strips where bedrock is adjacent to clays. Till and varved glacial clays would have been used for cultivation. A reasonable estimation is that 10% of the study area could have been used for cultivation 1900 C-14 years BP, compared to 28% in the end of the 17th century. During the last century there has been a shift towards more arable fields and more forestry. There are 10% open or semi-open grassland left today, and 6% wooded grassland, compared with 47% open or semi-open grassland in the 17th century. Little more than half of the open grasslands are managed today, all by grazing. It is argued that encroachment of trees and shrubs on open or semi-open grasslands will not only reduce species richness in the landscape but also threaten parts of our cultural heritage.
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| 2. |
- Mörtberg, Ulla M., et al.
(författare)
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Red-listed forest bird species in an urban environment - Assessment of green space corridors
- 2000
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Ingår i: Landscape and Urban Planning. - 0169-2046 .- 1872-6062. ; 50:4, s. 215-226
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Tidskriftsartikel (refereegranskat)abstract
- The aim of this work was to investigate if the forest remnants of the city and the system of green space corridors could support target species for conservation, in the form of red-listed forest bird species, to show through the presence of the target species what habitat qualities are still possible near cities, and to reveal those features and properties of the landscape structure that were important in this sense. The findings could be used for developing guidelines for design of urban green space corridors. A spatial analysis was performed, covering the landscape in the study area and 67 sample sites with natural vegetation, within and outside of the green space corridors. Breeding forest birds were recorded and breeding of target species in the sample sites as functions of landscape descriptors was tested using logistic regression. Seven red-listed forest bird species were found breeding in the sample sites. Considering them as indicators of habitat qualities, the results would imply that the qualities of the urban and suburban forests were due to a vast range of deciduous forest, especially broad-leaved, and possibly also to a lower intensity of forestry than in rural areas, resulting in a sufficient number of mature and decaying trees. The logistic regression models showed that important properties of remnants of natural vegetation were large areas of forest on rich soils, together with connectivity in the form of amounts of this habitat in the landscape. These properties were associated with the green space corridors. Implications for the design of urban green space corridors would be to treat mature and decaying trees and patches of moist deciduous forest as a resource for vulnerable species, and to conserve large areas of natural vegetation together with a network of important habitats in the whole landscape, in this case forest on rich soils, also in built-up areas.
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| 3. |
- Ruth-Balaganskaya, Ekaterina, et al.
(författare)
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Soil nutrient status and revegetation practices of downhill skiing areas in Finnish Lapland : a case study of Mt. Ylläs
- 2000
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Ingår i: Landscape and Urban Planning. - 0169-2046 .- 1872-6062. ; 50:4, s. 259-268
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Tidskriftsartikel (refereegranskat)abstract
- Ski slope construction is one of the major anthropogenic factors responsible for ecosystem degradation in mountain areas in Finnish Lapland. Mt. Yllas has been used as a downhill skiing slope for about 30 years. Until 1992, the ski slopes were kept in their natural condition: There was no removal of vegetation and soil above the tree line. After 1992, Mt. Yllas went through an extensive construction, the ski slopes were machine-graded and machine-levelled, which caused damage to both vegetation and soil. The aim of the study presented here was to examine nutrient status of various soils on the machine-graded and machine-levelled ski slopes in relation to their potential use as a substrate for revegetation practices. Soil organic matter and nutrient status were analysed in three sites on the slopes of Mt. Yllas in the tree line zone (transit zone between wooded vegetation and treeless alpine vegetation): (1) reference site on the undisturbed area between the ski-runs (Control); (2) disturbed site on the ski-run area (DSP - 'DiSturbed Podzol', - DSL 'DiSturbed Leptosol' and DSB - 'DiSturbed Bare soil'); and (3) Revegetation study Plots established on the ski-runs (RP). The analysis of element concentrations and their relative proportions allow us to conclude that only DSP and DSL can be considered as potentially appropriate for unassisted ecosystem recovery on the ski-runs. Presence of native plant species on these patches supports our conclusion. As a recommendation for revegetation of ski-runs, we propose implementation of substrate composed of upper layer of initial soil. Such substrate can be collected during the construction work on ski slopes or on building sites in the area with similar soils. Uncomposted substrate or at least short period of composting is preferable.
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