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Forest Fragmentation and Landscape Transformation in a Reindeer Husbandry Area in Sweden 总被引:1,自引:0,他引:1
Reindeer husbandry and forestry are two main land users in boreal forests in northern Sweden. Modern forestry has numerous
negative effects on the ground-growing and arboreal lichens that are crucial winter resources for reindeer husbandry. Using
digitized historical maps, we examined changes in the forest landscape structure during the past 100 years, and estimated
corresponding changes in suitability of forest landscape mosaics for the reindeer winter grazing. Cover of old coniferous
forests, a key habitat type of reindeer herding system, showed a strong decrease during the study period, whereas clear-cutting
and young forests increased rapidly in the latter half of the 20th century. The dominance of young forests and fragmentation
of old-growth forests (decreased patch sizes and increased isolation) reflect decreased amount of arboreal lichens as well
as a lowered ability of the landscape to sustain long-term persistence of lichens. The results further showed that variation
in ground lichen cover among sites was mainly related to soil moisture conditions, recent disturbances, such as soil scarification
and prescribed burning, and possibly also to forest history. In general, the results suggest that the composition and configuration
of the forest landscape mosaic has become less suitable for sustainable reindeer husbandry. 相似文献
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Boreal forests in Sweden are exploited in a number of ways, including forestry and reindeer husbandry. In the winter, reindeer
feed mainly on lichens, and lichen-rich forests are a key resource in the herding system. Commercial forestry has mainly negative
effects on reindeer husbandry, and conflicts between these two industries have escalated over the last century. This article
reviews the effects of modern forest management practices on the winter resources available for reindeer husbandry. Forestry
affects reindeer husbandry at both the stand level and the landscape level and over various time scales. Clear-cutting, site
preparation, fertilization, short rotation times, and forest fragmentation have largely resulted in a reduced amount of ground
growing and arboreal lichens and restricted access to resource. This article also discusses alternative forestry practices
and approaches that could reduce the impacts of forestry on reindeer husbandry, both in the short and long term. 相似文献
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Tailings containing toxic qualities of heavy metals are a potential source of pollution. Stabilisation by vegetative methods have been found the most effective. In an attempt to vegetate tailings dams it has been noted that while certain milky latex containing plants can be grown without any preconditioning of the soil, almost any plant can be grown after proper conditioning. However, the plants grown there cannot be consumed by humans or cattle due to their high metal content. 相似文献
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Jonas Rønningsdalen Kunst Gøril Kvamme Løset Daniel Hosøy Bjørn Bjorvatn Bente E. Moen Nils Magerøy 《International journal of occupational safety and ergonomics》2013,19(1):139-147
The aim of the present study was to estimate spillover effects between the work and the family sphere in a sample of nurses (N = 2058). Hierarchical regression analyses investigated whether shift work schedules were associated with negative or positive spillover, both from family to work and vice versa, controlling for demographic factors, job demands and decision latitude. With daytime work as a reference group, all types of shift work (day and evening shift, night shift only and rotating 3 shift) were associated with higher negative work-to-family spillover. Night work was associated with significantly less negative family-to-work spillover. None of the different shift work schedules were related to any type of positive spillover. The results indicate that working outside of daytime hours is less compatible with workers’ family lives, compared to working ordinary day shifts. On the other hand, working night shifts only was associated with reduced negative family-to-work spillover. 相似文献
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Comparison of regression coefficient and GIS-based methodologies for regional estimates of forest soil carbon stocks 总被引:4,自引:0,他引:4
Campbell JE Moen JC Ney RA Schnoor JL 《Environmental pollution (Barking, Essex : 1987)》2008,152(2):267-273
Estimates of forest soil organic carbon (SOC) have applications in carbon science, soil quality studies, carbon sequestration technologies, and carbon trading. Forest SOC has been modeled using a regression coefficient methodology that applies mean SOC densities (mass/area) to broad forest regions. A higher resolution model is based on an approach that employs a geographic information system (GIS) with soil databases and satellite-derived landcover images. Despite this advancement, the regression approach remains the basis of current state and federal level greenhouse gas inventories. Both approaches are analyzed in detail for Wisconsin forest soils from 1983 to 2001, applying rigorous error-fixing algorithms to soil databases. Resulting SOC stock estimates are 20% larger when determined using the GIS method rather than the regression approach. Average annual rates of increase in SOC stocks are 3.6 and 1.0 million metric tons of carbon per year for the GIS and regression approaches respectively. 相似文献