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1.
Ecol Evol ; 13(7): e10238, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37404696

RESUMO

Retention of structural elements such as deadwood and habitat trees at the level of forest stands has been promoted to integrate biodiversity conservation into multiple-use forest management. The conservation value of habitat trees is largely determined by the presence, richness, and abundance of tree-related microhabitats (TreMs). Since TreMs are often lacking in intensively managed forests, an important question of forest conservation is how the abundance and richness of TreMs may be effectively restored. Here, we investigated whether the strict protection of forest through cessation of timber harvesting influenced TreM occurrence at tree and stand levels. For that purpose, we compared four managed and four set-aside stands (0.25 ha each) in the Bialowieza Forest, with identical origin following clear-cuts approximately 100 years ago. We found that the abundance and richness of TreMs on living trees were not significantly different between stands that were either conventionally managed or where active forest management ceased 52 years ago. Yet, our analysis of TreMs on tree species with contrasting life-history traits revealed that short-lived, fast-growing species (pioneers) developed TreMs quicker than longer-lived, slower-growing species. Hence, tree species such as Populus or Betula, which supply abundant and diverse TreMs, can play an important role in accelerating habitat restoration.

2.
PLoS One ; 16(10): e0258398, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34648553

RESUMO

Honey bees are currently facing mounting pressures that have resulted in population declines in many parts of the world. In northern climates winter is a bottleneck for honey bees and a thorough understanding of the colonies' ability to withstand the winter is needed in order to protect the bees from further decline. In this study the influence of weather variables on colony weight loss was studied over one winter (2019-2020) in two apiaries (32 colonies in total) in southwestern Sweden with weather stations recording wind and temperature at 5-min intervals. Three subspecies of honey bees and one hybrid were studied: the native Apis mellifera mellifera, the Italian A. m. ligustica, the Carniolan A. m. carnica and the hybrid Buckfast. Additionally, we recorded Varroa mite infestation. To analyze factors involved in resource consumption, three modelling approaches using weather and weight data were developed: the first links daily consumption rates with environmental variables, the second modelled the cumulative weight change over time, and the third estimated weight change over time taking light intensity and temperature into account. Weight losses were in general low (0.039 ± 0.013kg/day and colony) and comparable to southern locations, likely due to an exceptionally warm winter (average temperature 3.5°C). Weight losses differed only marginally between subspecies with indications that A. m. mellifera was having a more conservative resource consumption, but more studies are needed to confirm this. We did not find any effect of Varroa mite numbers on weight loss. Increased light intensity and temperature both triggered the resource consumption in honey bees. The temperature effect on resource consumption is in accordance with the metabolic theory of ecology. The consequences of these findings on honey bee survival under predicted climate changes, is still an open question that needs further analysis.


Assuntos
Criação de Abelhas/métodos , Abelhas/fisiologia , Animais , Infestações por Ácaros/diagnóstico , Infestações por Ácaros/parasitologia , Modelos Teóricos , Estações do Ano , Luz Solar , Suécia , Temperatura , Varroidae/fisiologia , Redução de Peso
3.
Ecol Evol ; 10(2): 1029-1041, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32015862

RESUMO

The shift from shade-intolerant species to shade-tolerant mesophytic species in deciduous and mixed forests of the temperate zone is well described in studies from North America. This process has been termed mesophication and it has been linked to changes in fire regime. Fire suppression results in the cessation of establishment of heliophytic, fire-dependent tree species such as oak (Quercus) and pine (Pinus). Due to the scarcity of old-growth forests in Europe, data on long-term compositional changes in mixed forests are very limited, as is the number of studies exploring whether fire played a role in shaping the dynamics.The aim of this study was to reconstruct tree succession in a 43-ha natural mixed deciduous forest stand in Bialowieza Forest (BF), Poland using dendrochronological methods. In addition, the presence of aboveground fire legacies (charred and fire-scarred deadwood) enabled the fire history reconstruction.Dendrochronological data revealed tree establishment (Quercus) back to the end of the 1500s and fires back to 1659. Under a regime of frequent fires until the end of the 18th century, only oak and pine regenerated, sporadically. A shift in the fire regime in the first half of the 19th century triggered oak and pine cohort regeneration, then gradually spruce (Picea) encroached. Under an increasingly dense canopy and less flammable conditions, regeneration of shade-tolerant Carpinus, Tilia, and Acer began simultaneously with the cessation of oak and pine recruitment. Synthesis. The study reports the first evidence of mesophication in temperate Europe and proves that fire was involved in shaping the long-term dynamics of mixed deciduous forest ecosystems. Our data suggest that fire exclusion promoted a gradual recruitment of fire-sensitive, shade-tolerant species that inhibited the regeneration of oak and pine in BF.

4.
Artigo em Inglês | MEDLINE | ID: mdl-31817472

RESUMO

Nature-based interventions have been proposed to promote physical and mental health and give stress reduction. Little attention has been given to the potential of zoos for human health and wellbeing. A disadvantaged group in Sweden regarding access to nature are individuals with disabilities who consequently do not have the same access to these health benefits as other groups. To increase awareness and knowledge regarding spending time in nature and with animals, courses directed at caretakers for persons with disabilities and their users were held at Nordens Ark, a zoo in Sweden. To explore if the courses had led to increased nature activities, and if participating in the courses had affected caretakers' and their users' health and wellbeing, questionnaires and interviews for evaluating the courses were used. The results showed improved quality in nature visits because of course participation as well as positive effects for the wellbeing, sustainability for the caregivers and users in their working lives, and relationships were positively affected. The conclusion from this study is that nature and animal-based education should be more frequent to provide opportunities for a disadvantaged group to have the positive effects of nature of which most other groups have obvious access to.


Assuntos
Animais Selvagens , Cuidadores/psicologia , Pessoas com Deficiência/psicologia , Saúde Mental , Parques Recreativos , Animais , Família , Nível de Saúde , Humanos , Masculino , Inquéritos e Questionários , Suécia
5.
Front Psychol ; 9: 2409, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30564173

RESUMO

This focused review is based on earlier studies which have shown that both children and adults diagnosed as having developmental coordination disorder (DCD), benefited from sensorimotor therapy according to the method Retraining for Balance (RB). Different approaches and assessments for children and adults in regard to DCD are scrutinized and discussed in comparison to RB which mainly includes (a) vestibular assessment and stimulation (b) assessment and integration of aberrant primary reflexes and (c) assessment and stimulation of auditory and visual perception. Earlier results indicate that the process of Sensorimotor therapy using RB techniques could be described according to a conceptual Kinesthetic-Vestibular Developmental Model (KVDM) whereby the training elicited temporary physical and psychological regressions followed by transformations i.e., positive physical and psychological development. We have also seen that this recurring pattern is similar for children and adults. In our conceptual model vestibular stimulation (perceptual priming) stimulates the nervous system, which might enhance object-related priming. This perceptual priming will also assist the suppression of persistent aberrant primary reflexes. In order to develop effective methods for assessment and intervention of DCD over the life span the importance of primary reflex inhibition and vestibular stimulation as well as a combination of bottom-up and top-down approaches have to be considered.

6.
PLoS One ; 12(10): e0186126, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29020061

RESUMO

The aims of the present study were to (a) compare healthy children in terms of sensorimotor maturity to untreated children diagnosed with developmental coordination disorder (DCD) and (b) compare healthy children to diagnosed children following completed treatment with sensorimotor therapy. Participants were 298 children, 196 boys and 102 girls, distributed into a Norm group of healthy children (n = 99) and a group of children diagnosed with DCD (n = 199) with a total mean age of 8.77 years (SD = 2.88). Participants in both groups were assessed on instruments aimed to detect sensorimotor deviations. The children in the DCD group completed, during on average 36 months, sensorimotor therapy which comprised stereotypical fetal- and infant movements, vestibular stimulation, tactile stimulation, auditory stimulation, complementary play exercises, gross motor milestones, and sports-related gross motor skills. At the final visit a full assessment was once more performed. Results showed that the Norm group performed better on all sensorimotor tests as compared to the untreated children from the DCD group, with the exception of an audiometric test where both groups performed at the same level. Girls performed better on tests assessing proprioceptive and balance abilities. Results also showed, after controls for natural maturing effects, that the children from the DCD group after sensorimotor therapy did catch up with the healthy children. The concept of "catching-up" is used within developmental medicine but has not earlier been documented with regard to children and youth in connection with DCD.


Assuntos
Transtornos das Habilidades Motoras/fisiopatologia , Transtornos das Habilidades Motoras/terapia , Córtex Sensório-Motor/fisiopatologia , Adolescente , Audiometria , Estudos de Casos e Controles , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Orientação/fisiologia , Equilíbrio Postural/fisiologia , Reflexo/fisiologia
7.
Sci Rep ; 6: 22532, 2016 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-26940995

RESUMO

Understanding the drivers of the boreal forest fire activity is challenging due to the complexity of the interactions driving fire regimes. We analyzed drivers of forest fire activity in Northern Scandinavia (above 60 N) by combining modern and proxy data over the Holocene. The results suggest that the cold climate in northern Scandinavia was generally characterized by dry conditions favourable to periods of regionally increased fire activity. We propose that the cold conditions over the northern North Atlantic, associated with low SSTs, expansion of sea ice cover, and the southward shift in the position of the subpolar gyre, redirect southward the precipitation over Scandinavia, associated with the westerlies. This dynamics strengthens high pressure systems over Scandinavia and results in increased regional fire activity. Our study reveals a previously undocumented teleconnection between large scale climate and ocean dynamics over the North Atlantic and regional boreal forest fire activity in Northern Scandinavia. Consistency of the pattern observed annually through millennium scales suggests that a strong link between Atlantic SST and fire activity on multiple temporal scales over the entire Holocene is relevant for understanding future fire activity across the European boreal zone.

8.
Ambio ; 45 Suppl 2: 124-39, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26744048

RESUMO

Whereas there is evidence that mixed-species approaches to production forestry in general can provide positive outcomes relative to monocultures, it is less clear to what extent multiple benefits can be derived from specific mixed-species alternatives. To provide such insights requires evaluations of an encompassing suite of ecosystem services, biodiversity, and forest management considerations provided by specific mixtures and monocultures within a region. Here, we conduct such an assessment in Sweden by contrasting even-aged Norway spruce (Picea abies)-dominated stands, with mixed-species stands of spruce and birch (Betula pendula or B. pubescens), or spruce and Scots pine (Pinus sylvestris). By synthesizing the available evidence, we identify positive outcomes from mixtures including increased biodiversity, water quality, esthetic and recreational values, as well as reduced stand vulnerability to pest and pathogen damage. However, some uncertainties and risks were projected to increase, highlighting the importance of conducting comprehensive interdisciplinary evaluations when assessing the pros and cons of mixtures.


Assuntos
Conservação dos Recursos Naturais , Agricultura Florestal/métodos , Mudança Climática , Ecossistema , Incêndios , Controle de Pragas , Suécia , Qualidade da Água , Vento
9.
Front Psychol ; 6: 480, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25954233

RESUMO

The aim of the study was to investigate, for the first time, if it is possible to integrate primary reflexes in adults with sensorimotor disorders through sensorimotor therapy (SMT). Participants consisted of 14 adults, one man and 13 women, with an average age of 35 years who completed a SMT program over 3 years. They were compared with a reference group of 100 youngsters spanning from 11 to 17 years. Procedures were the same for both youngsters and adults including regular visits to a therapist and training ~15 min each day at home throughout therapy. Assessments of sensorimotor abilities were made before and after the therapy. Results showed significant improvements on all measurements with regard to treatment for both age groups and the main picture indicated small differences between age groups. After therapy adults were better on balance and orientation tests while the youngsters performed better on sports related gross motor movements, processing of speech sounds and had acquired a better relation between visual skills and vestibular function. Conclusions were that motor problems do not disappear with age and that the same diagnostic instruments and treatment methods can be used for both children and adults with sensorimotor difficulties.

10.
Percept Mot Skills ; 117(2): 647-50, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24611264

RESUMO

In a recent study, Lin, Wu, Lin, Wu, Wu, and Kuo (2012) contributed to the theory of sensory integration by showing a high correlation between postural movement and bilateral motor integration. However, in their analysis, the authors excluded a subscale measuring reflex integration, since they regarded its items as being unconnected to postural movement and bilateral motor integration. This comment offers a complementary view and suggests that there may be a connection with reflex integration.


Assuntos
Destreza Motora , Movimento , Postura , Feminino , Humanos , Masculino
12.
Percept Mot Skills ; 108(3): 643-69, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19725302

RESUMO

The current naturalistic study examined whether sensorimotor therapy utilizing the training program, Retraining for Balance, might be an appropriate technique for sensorimotor proficiency. The 232 children (181 boys, 51 girls), whose mean age was 9.3 yr. (SD = 2.7), presented attentional and motor difficulties (according to the School Health Care) as indicated by their parents before starting therapy. The children were divided into three groups, i.e., a younger group (7 yr. old or younger, n = 65), a middle group (8 to 10 yr. old, n = 91), and an older group (11 yr. old or older, n = 76). The program has seven parts, including fetal and neonatal movements, vestibular and auditory perceptual stimulation, and gross motor movements, among others. The treatment period was close to 3 yr. on the average. Analyses in a repeated-measures design indicated significant improvement of sensorimotor skills among the three age groups, but the older children performed better than the others on several tests. There were only a few sex differences. Retraining for Balance may be a functional technique for training children and youth with sensorimotor difficulties and might constitute a complement to regular treatment of Developmental Coordination Disorder, Learning Disability, and ADHD, but controlled studies are necessary before more decisive conclusions can be drawn.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/terapia , Transtornos das Habilidades Motoras/terapia , Modalidades de Fisioterapia , Desempenho Psicomotor/fisiologia , Vestíbulo do Labirinto/fisiologia , Criança , Terapia por Estimulação Elétrica , Feminino , Humanos , Masculino , Destreza Motora/fisiologia , Equilíbrio Postural/fisiologia
13.
Philos Trans R Soc Lond B Biol Sci ; 363(1501): 2353-8, 2008 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-18006412

RESUMO

Fire, being both a natural and cultural phenomenon, presents problems in disentangling the historical effect of humans from that of climate change. Here, we investigate the potential impact of humans on boreal fire regimes from a perspective of fuels, ignitions and culture. Two ways for a low technology culture to impact the fire regime are as follows: (i) by altering the number of ignitions and their spatial distribution and timing and (ii) by hindering fire spread. Different cultures should be expected to have quite different impacts on the fire regimes. In northern Fennoscandia, there is evidence for fire regime changes associated with the following: a reindeer herding culture associated with few ignitions above the natural; an era of cattle husbandry with dramatically increased ignitions and somewhat higher fire frequency; and a timber exploitation era with decreasing fire sizes and diminishing fire frequency. In other regions of the boreal zone, such schemes can look quite different, but we suggest that a close look at the resource extraction and land use of different cultures should be part of any analysis of past fire regimes.


Assuntos
Cultura , Ecossistema , Incêndios , Agricultura Florestal/métodos , Atividades Humanas , Árvores , Europa (Continente) , Humanos
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