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1.
Pest Manag Sci ; 77(2): 620-627, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-32909328

RESUMEN

BACKGROUND: Moose (Alces alces L.) populations and moose damage in forests are debated in Nordic countries with dense moose populations. Moose populations and food resources vary greatly, both spatially and temporally, and reliable data covering both variables simultaneously at the same scale have seldom been available. We modelled the effect of moose population density and forest resources on the area of moose damage at regional scale, referring to moose management areas (MMA). Forest data and moose damage data originated from the Finnish National Forest Inventory, and the moose population data came from a Bayesian moose model. For modelling, average values of moose population, damage and forest variables were calculated for the periods 2004-2008 and 2009-2013 for each MMA. The MMAs were further classified into one of four larger geographical zones. The area of moose damage was used as a dependent variable, and the proportions of different types of forests and moose population densities per land area or area of seedling stands as explanatory variables. The relationships were modelled with a linear mixed-effects model with an exponential spatial correlation structure. RESULTS: The area of moose damage was best explained by total forest area, proportions of plantations and mature forests, and moose population density per land area or the proportion of plantations. There were differences among the biogeographical zones in how different variables explained the amount of damage. CONCLUSION: The results provide tools for analyzing the regional effects of moose population density and the amount of food resources on the amount of moose damage. This information can be used in reconciling sustainable moose population levels and the amount of damage.


Asunto(s)
Ciervos , Plantones , Animales , Teorema de Bayes , Bosques , Densidad de Población
2.
Data Brief ; 31: 105724, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32478157

RESUMEN

We present the first dataset that can be used to associate peoples' opinions with comprehensive biodiversity and cultural heritage values. The socio-ecological dataset includes 1) place-based information on peoples' recreational activities, values expressed as pleasant and unpleasant sites, and negative preferences concerning land use in terms of tourism, nature protection and forestry, and 2) compiled information on scored biodiversity values and protection level of sites. The data are organized in 1ha grid cells. The data were compiled from a rural nature-based tourism area in two municipalities northern Finland. Peoples' opinions were assessed using a public participation geographic information system (PPGIS) and the data were merged with spatial biodiversity data from the same area. The data are directly related to the article Tolvanen et al. [1]. Biodiversity data, also utilized in Tolvanen et al. 2020, were compiled from various sources and scoring was done in Kangas et al. [2]. References to individual respondents and spatial locations of markings were removed. The data are useful in evaluating the relationship between people's values and biodiversity.

3.
J Chem Ecol ; 34(11): 1382-91, 2008 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-18946705

RESUMEN

We investigated latitudinal and regional variations in the composition and concentrations of foliar flavonoids and condensed tannins in wild populations of white birch (Betula pubescens EHRH) in a large climatic transect in Finland. Concentrations of quercetin derivatives were correlated positively with latitude. By contrast, the concentrations of apigenin and naringenin derivatives were correlated negatively with latitude. These compound-specific latitudinal gradients compensated each other, resulting in no changes in the concentration of total flavonoids. Our results thus demonstrate a qualitative, but not quantitative, latitude-associated gradient in the foliar flavonoids in white birch. Due to higher antioxidant capacity of the quercetin derivatives in relation to other flavonoids, the qualitative change can reflect higher adaptation to light in the north than south. An investigation on a regional scale in the northern boreal zone showed that the temperature sum was correlated positively and soil P concentration was correlated negatively with the concentrations of foliar flavonoid, while the concentration of condensed tannins was correlated with slope. The variation in concentrations of flavonoids at large-scale geographical patterns is in line with the conjecture that foliar flavonoids are synthesized for protection against photooxidative stress.


Asunto(s)
Antioxidantes/análisis , Betula/química , Quercetina/análisis , Antiulcerosos/análisis , Antioxidantes/aislamiento & purificación , Apigenina/análisis , Finlandia , Flavanonas/análisis , Flavonoides/aislamiento & purificación , Hojas de la Planta/química , Quercetina/aislamiento & purificación , Suelo , Taninos/análisis , Temperatura
4.
Oecologia ; 155(3): 479-86, 2008 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-18080142

RESUMEN

The loss and fragmentation of forest habitats have been considered to pose a worldwide threat to the viability of forest-dwelling animals, especially to species that occupy old forests. We investigated whether the annual survival of sedentary male Tengmalm's owls Aegolius funereus was associated with the cover of old coniferous forests in Finland. Survival and recapture probabilities varied annually with density changes in populations of the main prey (Microtus voles). When this variation was controlled for, and relationships between survival and proportions of the three different forest age classes (old-growth, middle-aged, and young) were modeled separately, the old-growth model was the most parsimonious. Survival increased with the cover of old forest, although the extent of old forest within owl territories was relatively small (mean approximately 12%, range 2-37%). This association, however, varied among years and appeared especially in years of increasing vole abundance. At such times, old forests may sustain high populations of bank voles Clethrionomys glareolus, shrews and small passerines. In addition, old forests may serve as refuges against large avian predator species, such as Ural owls Strix uralensis and goshawks Accipiter gentilis. Our results suggest that changes in habitat quality created by agriculture and forestry may have the potential to reduce adult survival, an essential component of fitness and population viability.


Asunto(s)
Ecosistema , Modelos Biológicos , Estrigiformes/fisiología , Animales , Arvicolinae , Femenino , Finlandia , Masculino
5.
J Anim Ecol ; 76(2): 392-401, 2007 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-17302847

RESUMEN

1. Habitat heterogeneity has important repercussions for species abundance, demography and life-history patterns. While habitat effects have been more thoroughly studied in top-down situations (e.g. in association with predation), their role in bottom-up situations (e.g. in association with food abundance) has been less explored and the underlying mechanism(s) behind the ecological patterns have not commonly been identified. 2. With material from 1993 to 2003, we test the hypothesis that the reproduction of Finnish northern goshawks Accipiter gentilis (L.) is bottom-up limited by habitat composition, especially in situations where the density of their main prey (grouse) is low. Special emphasis was placed on identifying the mechanism(s) behind potential habitat effects. 3. While laying date and large-scale variation in the main prey density (but not habitat composition) were related to the number of eggs goshawks laid, small-scale differences in alternative prey density between different territories later influenced how many young were fledged via the mechanism of habitat-dependent partial-brood loss. As a result of this mechanism, a difference in nestling condition also arose between goshawk territories with differing habitat compositions. 4. As the relative proportions of different landscape elements in a given landscape is a function of large-scale differences in geomorphology and land use, this means that the reproductive performance of goshawks as averaged over larger scales can be understood correctly only in respect to the fact that habitat gradients differ across landscapes. 5. In addition to being one of the first papers identifying the mechanism of partial brood loss as being primarily responsible for the habitat-specific differences in the production of young, this study further illustrates the need to identify small-scale mechanisms to correctly understand the large-scale patterns of reproductive performance in territorial species. The repercussions of the observed habitat effect for local population development are discussed.


Asunto(s)
Ecosistema , Halcones/fisiología , Reproducción , Animales , Tamaño de la Nidada , Femenino , Finlandia , Galliformes , Masculino , Dinámica Poblacional , Conducta Predatoria , Árboles
6.
Ambio ; 35(5): 220-8, 2006 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16989506

RESUMEN

Using interdisciplinary field research in the Usa Basin, northeast European Russia, we compared local inhabitants' perception of environmental problems with chemical and remote-sensing signatures of environmental pollution and their local impacts. Extensive coal mining since the 1930s around Inta and Vorkuta has left a legacy of pollution, detected by measuring snowpack, topsoil, and lichen chemistry, together with remote-sensing techniques and analysis of lake water and sediments. Vorkuta and its environs suffered the worst impacts, with significant metal loading and alkalization in lakes and topsoils, elevated metals and cations in terricolous (reindeer) lichens, and changes in vegetation communities. Although the coal industry has declined recently, the area boasts a booming oil and gas industry, based around Usinsk. Local perceptions and concerns of environmental pollution and protection were higher in Usinsk, as a result of increased awareness after a major oil spill in 1994, compared with Vorkuta's inhabitants, who perceived air pollution as the primary environmental threat. Our studies indicate that the principal sources of atmospheric emissions and local deposition within 25 to 40 km of Vorkuta were coal combustion from power and heating plants, coal mines, and a cement factory. Local people evaluated air pollution from direct observations and personal experiences, such as discoloration of snow and respiratory problems, whereas scientific knowledge played a minor role in shaping these perceptions.


Asunto(s)
Contaminantes Ambientales/análisis , Percepción Social , Contaminantes Atmosféricos/análisis , Regiones Árticas , Minas de Carbón , Sistemas de Información Geográfica , Humanos , Federación de Rusia , Suelo/análisis , Contaminantes del Suelo/análisis , Contaminantes del Agua/análisis
7.
Proc Biol Sci ; 271(1537): 435-40, 2004 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-15101703

RESUMEN

We manipulated the primary brood size of Eurasian treecreepers (Certhia familiaris) breeding in different sized forest patches (0.5-12.8 ha) in moderately fragmented landscapes. We examined the effects of brood size manipulation (reduced, control, enlarged) and forest patch size on physiological stress (heterophil-lymphocyte ratios; H/L), body condition and cell-mediated immunocompetence (phytohaemagglutinin test). Nestlings' H/L ratios were negatively related to forest patch area in control and enlarged broods, whereas no effects were found in reduced broods. The effects of forest patch area were strongest in enlarged broods, which had, in general, twofold higher H/L ratios than control and reduced broods. The elevated H/L ratios were positively related to nestling mortality and negatively correlated with body-condition indices suggesting that the origin of stress in nestlings was mainly nutritional. Cell-mediated immunity of nestlings was not related to brood manipulation or to forest patch size. Also, the H/L ratios of adults were not related to brood manipulation or forest patch size. In addition, parental H/L ratios and body condition were not related to nestling H/L ratios. Our results suggest that during the breeding period the deleterious effects of habitat loss are seen explicitly in growing young.


Asunto(s)
Ambiente , Pájaros Cantores/inmunología , Pájaros Cantores/fisiología , Estrés Fisiológico/fisiopatología , Árboles , Animales , Finlandia , Leucocitos/inmunología , Modelos Lineales , Fitohemaglutininas/inmunología , Densidad de Población , Dinámica Poblacional
8.
Proc Biol Sci ; 270(1530): 2215-22, 2003 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-14613607

RESUMEN

We studied the primary brood sex ratio of an old-growth forest passerine, the Eurasian treecreeper (Certhia familiaris), along a gradient of forest fragmentation. We found evidence that male nestlings were more costly to produce, since they suffered twofold higher nestling mortality and were larger in body size than females. Furthermore, the proportion of males in the brood was positively associated with the provisioning rate and the amount of food delivered to the nestlings. During the first broods, a high edge density and a high proportion of pine forests around the nests were related to a decreased production of males. The densities of spiders, the main food of the treecreeper, were 38% higher on spruce trunks than on pine trunks. This suggests that pine-dominated territories with female-biased broods may have contained less food during the first broods. The observation was further supported by the fact that the feeding frequencies were lower in territories with high proportions of pines. In the second broods, territories with a high forest patch density produced female-biased broods, whereas high-quality territories with a large amount of deciduous trees and mixed forests produced male-biased broods. Our results suggest that habitat quality as measured by habitat characteristics is associated with sex allocation in free-living birds.


Asunto(s)
Ecología , Caracteres Sexuales , Razón de Masculinidad , Pájaros Cantores/fisiología , Árboles , Animales , Constitución Corporal/fisiología , Demografía , Dieta , Ambiente , Femenino , Masculino , Modelos Biológicos
9.
Proc Biol Sci ; 270(1518): 963-9, 2003 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-12803912

RESUMEN

We investigated how physiological stress in an area-sensitive old-growth forest passerine, the Eurasian treecreeper (Certhia familiaris), is associated with forest fragmentation and forest structure. We found evidence that the concentrations of plasma corticosterone in chicks were higher under poor food supply in dense, young forests than in sparse, old forests. In addition, nestlings in large forest patches had lower corticosterone levels and a better body condition than in small forest patches. In general, corticosterone levels were negatively related to body condition and survival. We also found a decrease in corticosterone levels within the breeding season, which may have been a result of an increase in food supply from the first to the second broods. Our results suggest that forest fragmentation may decrease the fitness of free-living individual treecreepers.


Asunto(s)
Enfermedades de las Aves/fisiopatología , Conservación de los Recursos Naturales , Agricultura Forestal , Pájaros Cantores/fisiología , Estrés Fisiológico/veterinaria , Animales , Animales Salvajes , Enfermedades de las Aves/sangre , Constitución Corporal , Corticosterona/sangre , Abastecimiento de Alimentos , Agricultura Forestal/métodos , Estrés Fisiológico/sangre , Estrés Fisiológico/fisiopatología
10.
Environ Pollut ; 120(3): 647-58, 2002.
Artículo en Inglés | MEDLINE | ID: mdl-12442788

RESUMEN

In this paper we present what kind of human impacted changes can be found in dwarf birch (Betula nana) dominated shrub tundra vegetation around the large industrial complex of Vorkuta in the north-European Russian tundra. Using fieldwork data and Landsat TM satellite image we could identify two impact zones: (1) Pollution zone (150-200 km2). In this zone most of the lichen species are absent. Changes in vegetation communities' species composition in all main plant groups are obvious. Willows especially are more dominant than in the unpolluted sites. (2) Slight pollution/disturbance zone (600-900 km2). Here vegetation changes are mainly similar but less so than the changes in the first zone. Particularly, the amount of herbs and grasses is increased when compared to unpolluted areas. The pollution zones are spatially connected to the main emission sources in the area. Zones spread furthest to the northeast, matching the prevailing winds during winter.


Asunto(s)
Minas de Carbón , Contaminación Ambiental , Procesamiento de Imagen Asistido por Computador , Comunicaciones por Satélite , Regiones Árticas , Humanos , Plantas , Federación de Rusia
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