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81.
Identifying, managing and monitoring conflicts between forest biodiversity conservation and other human interests in Europe 总被引:3,自引:0,他引:3
Jari Niemel Juliette Young Didier Alard Miren Askasibar Klaus Henle Richard Johnson Mikko Kurttila Tor-Bjrn Larsson Simone Matouch Peter Nowicki Rosa Paiva Luigi Portoghesi Ren Smulders Alan Stevenson Urmas Tartes Allan Watt 《Forest Policy and Economics》2005,7(6):877-890
In this paper, circumstances where various human activities and interests clash with the conservation of forest biodiversity are examined, with particular focus on the drivers behind the conflicts. After identifying past and current human-related threats potentially leading to conflicts in forests, the paper will focus on conflict management and monitoring, with an emphasis on inclusionary stakeholder networks and a range of approaches towards sustainable land use. Three dimensions of conflicts are examined: substance (‘how things are’), procedure (‘how things are done’), and relationships (‘how people behave’). These relations will relate to three conflict management approaches: (1) technical, which may contribute to reduce or solve the conflict acting on the ‘substance’ dimension, (2) political, which may influence the ‘procedure’ dimension of the conflict establishing principles or rules, and (3) cultural, which may affect the ‘relationship’ dimension of the conflict. Finally, a general model of adaptive conflict management emphasising communication among the parties and a participatory approach that involves monitoring of the conflict resolution outcomes is proposed. The recognition that strong perceptions among stakeholders have the potential to aggravate conflicts is central to the concept of a inclusionary conflict management framework, improved communication between all stakeholders, and better awareness of the context of the conflicts is emphasised. 相似文献
82.
The effects of restorative grazing on the abundance of butterfly and moth species were studied in mesic semi-natural grasslands of SW Finland differing in management history: (1) old continuously grazed, (2) restored (with ca 5 years of reinitiated grazing), and (3) abandoned former pastures.Generalized linear modelling of species abundances and indicator species analysis produced qualitatively similar results. Only three species (Polyommatus icarus, Lycaena hippothoe and Camptogramma bilineatum) were most abundant in old pastures, whereas 12 species (Polyommatus semiargus, Polyommatus amandus, Brenthis ino, Aphantopus hyperantus, Scopula immorata, Idaea serpentata, Scotopteryx chenopodiata, Epirrhoe alternata, Cybosia mesomella, Polypogon tentacularius, Hypena proboscidalis and Cryptocala chardinyi) were most abundant in abandoned pastures. None of the old-pasture species had become more abundant in restored pastures. Three species, Epirrhoe hastulata, Xanthorhoe montanata and Chiasmia clathrata, occurred equally abundantly in abandoned and in restored pastures indicating a slow progress of restoration.Species associated with old pastures differed from species associated with abandoned pastures in their recent distributional changes in Finland. The species of old pastures showed decreasing trends, whereas those of abandoned pastures showed mainly increasing trends in their distribution. In five out of 11 species, the preferred successional stage differed markedly between this study and previous studies conducted in Central Europe.We conclude that (1) ca 5 years of restorative grazing in mesic grasslands has been insufficient for the colonisation of old-pasture species in the restored sites, (2) different management intensities are needed regionally for the maintenance of grassland insect diversity and (3) application of the knowledge on successional preferences of different species in conservation management, even in climatically similar regions, should be made with caution. 相似文献
83.
Mikko Kurttila Jouni Pykäläinen Pekka Leskinen 《European Journal of Forest Research》2006,125(1):67-78
New, cost efficient and voluntary biodiversity protection tools may require bidding price definition on part of the seller.
Both the seller and the buyer can withdraw from negotiations if they find that the conditions of the protection contract are
unacceptable. However, it can be very difficult for non-industrial, private landowners to define the bidding price demand
for their biodiversity objects. The terms of the protection contract, the production possibilities of the forest holding,
the forest owner’s multiple forest management goals and their substitutability, and the possible monetary subsidy paid for
biodiversity protection should all be simultaneously taken into account when estimating the owner’s price demand for protecting
the biodiversity object. This study strives to provide relief in resolving this problem by presenting an approach in which
the landowner’s utility–loss compensative subsidy can be defined based on the owner’s forest-holding level utility function
and the production possibilities of the holding. The properties of the approach are illustrated by four planning cases in
which the length of the protection period (permanent or 20-year temporary protection) and the holding-level goals were varied.
The utility functions of the cases were derived by selecting numeric goal variables for the goals, and by defining weights
and sub-utility functions for these variables. Varying subsidies for protecting an old-growth spruce stand were included into
the simulation of “No treatment” schedules for the examined stand, and the holding-level total utility was maximized for every
price level. The utility–loss compensative subsidy was found when the holding-level total utility equaled the total utility
achieved in the plan where the stand was regenerated. This subsidy, however, is not necessarily the exact price that the owner
should ask from the buyer; all prices above the defined subsidy level will increase owner’s utility if the buyer accepts them.
It was concluded that the presented approach provided consistent results in the four cases and that it thus offers valuable
decision support for current biodiversity-protection programs. 相似文献
84.
Mikko Havimo 《Wood Science and Technology》2009,43(7-8):627-642
In mechanical pulping, wood is dynamically loaded, which causes large heat losses due to wood viscoelasticity. The heat losses depend on the loss tangent (tan δ) of wood. The loss tangent has a temperature-dependent behaviour, especially in the lignin glass transition region. The glass transition softens wood, and is therefore necessary for gentle mechanical pulping, but at the same time, the loss tangent shows a maximum called the α-peak. The transient peak depends on temperature, loading frequency and moisture content. The temperature where the peak is found can be lowered with chemical treatments, but they also increase the magnitude of the peak. Thermal treatment in the presence of water also increases the magnitude. The loss tangent of wood depends, amongst other things, on the chemical structure of lignin, width of cellulose crystals, microfibril angle, and extractives in the cell wall. 相似文献
85.
Pekka Vanhala Kristiina Karhu Mikko Tuomi Katarina Björklöf Hannu Fritze Jari Liski 《Soil biology & biochemistry》2008,40(7):1758-1764
Much effort has been made to improve understanding of factors controlling the temperature dependence of soil organic matter (SOM) decomposition. The question of how soils formed in different geographical locations and conditions respond to temperature changes is still open. In addition to climate, residence times of soil organic matter are controlled by its decomposability and microbial community. In this work we hypothesized that the decomposition of SOM is adapted to the prevailing SOM quality and climatic conditions. This should result in different temperature vs. decomposition curves for northern and southern soils. We studied short-term temperature dependence of SOM decomposition near the northern and southern borders of the boreal forest zone using a Gaussian model. As carbon mineralization rate is driven by microbial activity, we focused on organic carbon fractions available to microbes and the size, composition and functioning of microbial communities in the soil. Despite differences in microbial community structure and behavior, similar amounts and qualities of the microbially available carbon led to similar temperature dependences of carbon mineralization in the north and south. The overall soil respiration rate level was higher in spruce forest sites than in pine forest sites irrespective of climate conditions. Our results do not mean that there is no risk of carbon losses from northern soils due to warming climate conditions. As temperature sensitivity of the decomposition increases with decreasing temperature regime, the proportional increase in the decomposition rate in northern latitudes might lead to significant carbon losses from the soils. 相似文献
86.
Mikko Tikkinen Saila Varis Heli Peltola Tuija Aronen 《Scandinavian Journal of Forest Research》2018,33(3):207-214
In the Nordic countries, Norway spruce (Picea abies) is a major species in tree breeding. In order to facilitate breeding work and availability of highly bred forest regeneration material, the time required for breeding and implementation of results should be shortened. This could be done by accelerating production of clonal material for field testing, and possibly for planting stock, by combining production of rooted cuttings with somatic embryogenesis (SE). This would allow efficient production of numerous plants of the same genotype, with equal age and propagation history between genotypes. In the present work, we studied the rooting potential of cuttings from Norway spruce emblings. Altogether 36 clones from 12 families representing elite breeding materials and ornamental forms were examined under different rooting conditions (container type and rooting media) in 2015 and 2016. Our results show that Norway spruce emblings are good donors for cuttings. Best combination (peat–vermiculite mixture and Plantek 81f containers) resulted in 91% rooting, variation among the tested clones of elite breeding materials being 55–100% per treatment. The rooting variation between families is acceptable for breeding purposes. High rooting (87–96%) of ornamental forms indicates propagation potential with the combination of SE and rooted cuttings. 相似文献
87.
Fine root biomass in relation to site and stand characteristics in Norway spruce and Scots pine stands 总被引:8,自引:0,他引:8
Variations in fine root biomass of trees and understory in 16 stands throughout Finland were examined and relationships to site and stand characteristics determined. Norway spruce fine root biomass varied between 184 and 370 g m(-2), and that of Scots pine ranged between 149 and 386 g m(-2). In northern Finland, understory roots and rhizomes (< 2 mm diameter) accounted for up to 50% of the stand total fine root biomass. Therefore, the fine root biomass of trees plus understory was larger in northern Finland in stands of both tree species, resulting in a negative relationship between fine root biomass and the temperature sum and a positive relationship between fine root biomass and the carbon:nitrogen ratio of the soil organic layer. The foliage:fine root ratio varied between 2.1 and 6.4 for Norway spruce and between 0.8 and 2.2 for Scots pine. The ratio decreased for both Norway spruce and Scots pine from south to north, as well as from fertile to more infertile site types. The foliage:fine root ratio of Norway spruce was related to basal area and stem surface area. The strong positive correlations of these three parameters with fine root nitrogen concentration implies that more fine roots are needed to maintain a certain amount of foliage when nutrient availability is low. No significant relationships were found between stand parameters and fine root biomass at the stand level, but the relationships considerably improved when both fine root biomass and stand parameters were calculated for the mean tree in the stand. When the northern and southern sites were analyzed separately, fine root biomass per tree of both species was significantly correlated with basal area and stem surface area per tree. Basal area, stem surface area and stand density can be estimated accurately and easily. Thus, our results may have value in predicting fine root biomass at the tree and stand level in boreal Norway spruce and Scots pine forests. 相似文献
88.
Brommer H Laasanen MS Brama PA van Weeren PR Barneveld A Helminen HJ Jurvelin JS 《American journal of veterinary research》2005,66(7):1175-1180
OBJECTIVE: To determine the speed of sound (SOS) in equine articular cartilage and investigate the influence of age, site in the joint, and cartilage degeneration on the SOS. SAMPLE POPULATION: Cartilage samples from 38 metacarpophalangeal joints of 38 horses (age range, 5 months to 22 years). PROCEDURE: Osteochondral plugs were collected from 2 articular sites of the proximal phalanx after the degenerative state was characterized by use of the cartilage degeneration index (CDI) technique. The SOS was calculated (ratio of needle-probe cartilage thickness to time of flight of the ultrasound pulse), and relationships between SOS value and age, site, and cartilage degeneration were evaluated. An analytical model of cartilage indentation was used to evaluate the effect of variation in true SOS on the determination of cartilage thickness and dynamic modulus with the ultrasound indentation technique. RESULTS: The mean SOS for all samples was 1,696 +/- 126 m/s. Age, site, and cartilage degeneration had no significant influence on the SOS in cartilage. The analytical model revealed that use of the mean SOS of 1,696 m/s was associated with maximum errors of 17.5% on cartilage thickness and 70% on dynamic modulus in an SOS range that covered 95% of the individual measurements. CONCLUSIONS AND CLINICAL RELEVANCE: In equine articular cartilage, use of mean SOS of 1,696 m/s in ultrasound indentation measurements introduces some inaccuracy on cartilage thickness determinations, but the dynamic modulus of cartilage can be estimated with acceptable accuracy in horses regardless of age, site in the joint, or stage of cartilage degeneration. 相似文献
89.
Eija Hurme Mikko Kurttila Mikko Mönkkönen Tero Heinonen Timo Pukkala 《Landscape Ecology》2007,22(2):243-256
Spatial and temporal continuity of resources often benefits both ecological and economic goals in landscape management. Consideration
of multiple and conflicting goals is also needed to view the future production possibilities of forests in successful forest
management. Our aim was to estimate the production potential of a planning area in Finland by examining different forest management
strategies from ecological and economic perspectives using long-term forest planning calculations. Economic objectives referred
to timber production, whereas ecological objectives were based on suitable habitats for arboreal Siberian flying squirrel
(Pteromys volans). Suitable habitats were defined using an empirical site-specific model, which includes a spatial variable reflecting the
availability of habitat within an individual’s activity area. Five alternative forest plans were worked out with different
objectives for flying squirrel habitat and timber production. The alternative plans were compared with respect to values of
objective variables at the end of the planning period of 60 years and against a production possibility frontier among net
present value and flying squirrel habitat. Varying objective values in our analyses resulted from different utilization of
production possibilities, and the changes were in line with the objectives used. The formation of flying squirrel habitat
clusters in the landscape was enhanced, and it did not always incur severe reductions in harvestable timber volume. Possibilities
to combine ecological and economic goals, both spatial and aspatial, in the planning process seems to be an encouraging alternative
for the long-term forest management in the future. 相似文献
90.
Adriano Mazziotta Mikko Mönkkönen Harri Strandman Johanna Routa Olli-Pekka Tikkanen Seppo Kellomäki 《European Journal of Forest Research》2014,133(3):405-421
The present research examines the joint effects of climate change and management on the dead wood dynamics of the main tree species of the Finnish boreal forests via a forest ecosystem simulator. Tree processes are analyzed in stands subject to multiple biotic and abiotic environmental factors. A special focus is on the implications for biodiversity conservation thereof. Our results predict that in boreal forests, climate change will speed up tree growth and accumulation ending up in a higher stock of dead wood available as habitat for forest-dwelling species, but the accumulation processes will be much smaller in the working landscape than in set-asides. Increased decomposition rates driven by climate change for silver birch and Norway spruce will likely reduce the time the dead wood stock is available for dead wood-associated species. While for silver birch, the decomposition rate will be further increased in set-aside in relation to stands under ordinary management, for Norway spruce, set-asides can counterbalance the enhanced decomposition rate due to climate change thereby permitting a longer persistence of different decay stages of dead wood. 相似文献