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Forest owners and Indigenous Sami reindeer herders use the same land in northern Sweden for commercial forestry and winter grazing, respectively. Fire management has been controlled by foresters since the late-19th century, and Sami herders have had to deal with the effects of both fire suppression and prescribed burning. However, the environmental history of fire management and reindeer herding in Sweden has never been thoroughly investigated. We therefore analyzed written archives in order to understand how reindeer herding was considered in planned burning during the mid-20th century, and how the effects of prescribed burning on reindeer herding were interpreted by foresters. We supplemented the interpretation of written sources by including local Sami reindeer herders' insights about prescribed burning. Written records show that reindeer herding was increasingly integrated into the planning process during the 20th century, yet foresters failed to include important aspects of reindeer herding in their interpretation of the effects of prescribed burning. The Sami consider the effects of burning in terms of fodder availability, opportunities for reindeer to graze the fodder, and any impact on the reindeer's movement patterns and thus herd management. The Sami's historical perspective is essential in order to reconstruct a comprehensive picture of the past, and adapt forestry measures effectively in the future.
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Rena , Criação de Animais Domésticos , Animais , Agricultura Florestal , Suécia , TaigaRESUMO
BACKGROUND AND AIMS: The Piedra Chamana fossil forest in northern Peru is an assemblage of angiosperm woods and leaves preserved in volcaniclastic rocks dated to 39 Mya (late Middle Eocene). We analysed the anatomical and morphological features of the fossils to reconstruct the palaeoenvironment during this time of global warmth, taking advantage of the co-occurrence of woods and leaves to compare different proxies and analytical approaches. METHODS: Wood characters analysed include vessel-related functional traits, traits linked to Baileyan trends, and quantitative features such as vessel diameter and density. Diameter-distribution and diameter and position plots are used to represent vessel diameter and arrangement. Leaf margin and area analysis provides additional climate estimates. KEY RESULTS: The fossil woods show many similarities with modern tropical-forest woods and tropical fossil-wood assemblages; closest correspondence within the Neotropics is to semi-deciduous lowland tropical forest with moderate precipitation (~1000-1200 mm). Features unusual for the modern South American tropics are mainly vessel-related characters (semi-ring porosity, grouped vessels, helical vessel thickenings, short vessel elements) linked to water stress or seasonal water availability. Leaf analysis indicates mean annual temperature of 31 °C (n = 19, 100 % entire-margined) and mean annual precipitation of 1290 mm (n = 22, predominantly microphylls and notophylls). CONCLUSIONS: The palaeovegetation was clearly lowland tropical forest with a dry aspect, but anomalous aspects of the wood anatomy are consistent with the high temperatures indicated by the leaves and are probably explained by differences in seasonality and water stress compared to the present-day Neotropics. A close modern analogue may be in very seasonal regions of Asia. Pronounced monsoonal (summer-rain) conditions may relate to a location (palaeolatitude of 13°S) outside the near-equatorial tropics.
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Fósseis , Piedra , Ásia , Humanos , Peru , Folhas de Planta , Árvores , Clima Tropical , MadeiraRESUMO
A growing world population and rapid expansion of cities increase the pressure on basic resources such as water, food and energy. To safeguard the provision of these resources, restoration and sustainable management of landscapes is pivotal, including sustainable forest and water management. Sustainable forest management includes forest conservation, restoration, forestry and agroforestry practices. Interlinkages between forests and water are fundamental to moderate water budgets, stabilize runoff, reduce erosion and improve biodiversity and water quality. Sweden has gained substantial experience in sustainable forest management in the past century. Through significant restoration efforts, a largely depleted Swedish forest has transformed into a well-managed production forest within a century, leading to sustainable economic growth through the provision of forest products. More recently, ecosystem services are also included in management decisions. Such a transformation depends on broad stakeholder dialog, combined with an enabling institutional and policy environment. Based on seminars and workshops with a wide range of key stakeholders managing Sweden's forests and waters, this article draws lessons from the history of forest management in Sweden. These lessons are particularly relevant for countries in the Global South that currently experience similar challenges in forest and landscape management. The authors argue that an integrated landscape approach involving a broad array of sectors and stakeholders is needed to achieve sustainable forest and water management. Sustainable landscape management-integrating water, agriculture and forests-is imperative to achieving resilient socio-economic systems and landscapes.
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Conservação dos Recursos Naturais/métodos , Política Ambiental/tendências , Agricultura Florestal/organização & administração , Florestas , Árvores/crescimento & desenvolvimento , Qualidade da Água/normas , Agricultura/organização & administração , Biodiversidade , Agricultura Florestal/tendências , Crescimento Demográfico , Suécia , Árvores/classificação , UrbanizaçãoRESUMO
To reduce future loss of biodiversity and to allocate conservation funds effectively, the major drivers behind large-scale extinction processes must be identified. A promising approach is to link the red-list status of species and specific traits that connect species of functionally important taxa or guilds to resources they rely on. Such traits can be used to detect the influence of anthropogenic ecosystem changes and conservation efforts on species, which allows for practical recommendations for conservation. We modeled the German Red List categories as an ordinal index of extinction risk of 1025 saproxylic beetles with a proportional-odds linear mixed-effects model for ordered categorical responses. In this model, we estimated fixed effects for intrinsic traits characterizing species biology, required resources, and distribution with phylogenetically correlated random intercepts. The model also allowed predictions of extinction risk for species with no red-list category. Our model revealed a higher extinction risk for lowland and large species as well as for species that rely on wood of large diameter, broad-leaved trees, or open canopy. These results mirror well the ecological degradation of European forests over the last centuries caused by modern forestry, that is the conversion of natural broad-leaved forests to dense conifer-dominated forests and the loss of old growth and dead wood. Therefore, conservation activities aimed at saproxylic beetles in all types of forests in Central and Western Europe should focus on lowlands, and habitat management of forest stands should aim at increasing the amount of dead wood of large diameter, dead wood of broad-leaved trees, and dead wood in sunny areas.
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Besouros/fisiologia , Conservação dos Recursos Naturais , Extinção Biológica , Florestas , Animais , Europa (Continente) , Risco , Medição de RiscoRESUMO
European broadleaved forests have been influenced by humans for centuries. Historical management practices are related to environmental conditions but the role of socio-economic factors is also important. For the successful restoration of traditional management for conservation purposes, detailed knowledge on management history and on the driving forces of historical forest changes is necessary. In order to reconstruct long-term spatio-temporal dynamics in forest management, we chose the Pálava Protected Landscape Area, Czech Republic and analyzed archival sources spanning the past seven centuries. Forests in the study area comprise two relatively large woods (Devín and Milovice) with different environmental conditions. Historical forest management in both woods was coppicing. The coppice cycle was lengthened from 7 years (14th century) to more than 30 years (19th century) with a fluctuating density of standards. After WWII, coppicing was completely abandoned. This led to pronounced changes in forest age structure accompanied by stand unification indicated by a sharp decrease in the Shannon index of age diversity. To study local attributes responsible for spatial patterns in coppice abandonment, we constructed a regression model with the date of abandonment as a dependent variable and three groups of explanatory variables: i) remoteness of forest parcels, (ii) morphometric environmental factors and iii) site productivity. In Devín Wood, coppicing was abandoned gradually with the pattern of abandonment related significantly to slope steepness and forest productivity. Poorly accessible upper slopes and low productive forest sites were abandoned earlier. By contrast, in Milovice Wood, where no clear topographic gradient is present, the abandonment of coppicing was not related to any of the variables we studied. Our study brings insights into the history and consequences of past management practices, and can be used in current attempts to re-establish coppice management for conservation purposes and as a source of sustainable energy.
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Throughout history, humans have relied on wood for constructions, tool production or as an energy source. How and to what extent these human activities have impacted plant abundance and composition over a long-term perspective is, however, not well known. To address this knowledge gap, we combined 44,239 precisely dated tree-ring samples from economically and ecologically important tree species (spruce, fir, pine, oak) from historical buildings, and pollen-based plant cover estimates using the REVEALS model from 169 records for a total of 34 1° × 1° grid cells for Central Europe. Building activity and REVEALS estimates were compared for the entire study region (4-15°E, 46-51°N), and for low (<500 m asl) and mid/high elevations (≥500 m asl) in 100-year time windows over the period 1150-1850. Spruce and oak were more widely used in wooden constructions, amounting to 35 % and 32 %, respectively, compared to pine and fir. Besides wood properties and species abundance, tree diameters of harvested individuals, being similar for all four species, were found to be the most crucial criterion for timber selection throughout the last millennium. Regarding land use changes, from the 1150-1250's onwards, forest cover generally decreased due to deforestation until 1850, especially at lower elevations, resulting in a more heterogeneous landscape. The period 1650-1750 marks a distinct change in the environmental history of Central Europe; increasing agriculture and intense forest management practices were introduced to meet the high demands of an increasing population and intensifying industrialization, causing a decrease in palynological diversity, especially at low elevations. Likely the characteristic vegetation structure and composition of contemporary landscapes originated from that period. We further show that land use has impacted vegetation composition and diversity at an increasing speed leading to a general homogenization of landscapes through time, highlighting the limited environmental benefits of even-aged plantation forestry.
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Florestas , Pinus , Humanos , Idoso , Europa (Continente) , Madeira , Pólen , Agricultura Florestal , Conservação dos Recursos NaturaisRESUMO
At the mid-twentieth century the pace of the transformation of the Swedish forest increased. New methods; large-scale clearcutting, mechanization of logging and planting of seedlings were developed. Chemicals were used to control insects and unwanted tree species. The aims of this study were to elucidate the timing, chain of events and the spatial extent of the large-scale spraying of phenoxy acids in Swedish forests and the drivers for this practice. More than 700 000 hectares of productive forest land was sprayed and the main driving force was a strong will to transform the forest into high-yield coniferous forest plantations. We conclude that; (1) the use of herbicides in forestry in Sweden was done on a very large scale in the period 1948-1984, (2) the ecosystem legacy of herbicide spraying must be investigated and (3) a homogenous cadre of like-minded professionals working across commercial companies, state agencies and universities is dangerous.
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Herbicidas , Taiga , Ecossistema , Agricultura Florestal/história , Florestas , Suécia , ÁrvoresRESUMO
Ecotonal zones between eastern semi-arid steppes and Nothofagus spp. forests in western Patagonia are the result of broad ecosystem changes, which have intensified in the last 140 years. Our objectives were to determine historical changes in land use, land cover, and forces driving such changes in Nothofagus ecosystems in the Río Verde district in southern Chile, to support future management recommendations. This interdisciplinary study used historical records including scientific and military expeditions, Landsat imagery, and other archival sources. Forest cover changed radically between the late nineteenth and mid-twentieth centuries, from subsistence use by indigenous peoples, to forestry and livestock industries. The main driving forces of landscape change have been anthropogenic forest fires, logging, exotic pasture establishment, and mining. Future perspectives suggest that conserving the cultural values and natural resources of this region will depend on ecologically sound landscape planning, reversing forest fragmentation, restoring riparian corridors, and preserving indigenous archaeological sites.
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Conservação dos Recursos Naturais , Ecossistema , Chile , Ecologia , Florestas , ÁrvoresRESUMO
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.
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Resumen El Bosque Petrificado Piedra Chamana, cerca del pueblo de Sexi en Cajamarca, registra la vegetación de los trópicos de Sudamérica de hace 39 millones de años, la que existió en los inicios de la historia de los bosques tropicales del Nuevo Mundo y antes del levantamiento de los Andes. En este bosque, descubrimientos notables incluyen el manglar del género Avicennia, un género de árboles forestales emergentes (Cynometra), y el segundo dipterocarp conocido del Nuevo Mundo. La importancia de los fósiles se basa en sus circunstancias únicas de preservación, es así como fósiles de plantas y suelos antiguos permiten la reconstrucción detallada del bosque y el medio ambiente en que existieron, contribuyendo con el conocimiento del cambio climático. Los sitios como este bosque fósil son muy vulnerables al disturbio y pérdida de los recursos fósiles. El monitoreo muestra que las actividades humanas y la erosión están teniendo efectos serios y que son necesarias medidas urgentes para su conservación. La importancia de los fósiles para la ciencia, la belleza de esta área de los Andes, y el potencial para la educación y turismo justifican el reconocimiento del Bosque Petrificado Piedra Chamana a nivel internacional. El bosque tropical representado por los fósiles es muy diferente del bosque diverso esclerófilo de hoja ancha que se encuentra actualmente en el sitio. La pérdida del suelo y la erosión del substrato suave y poroso por alteración de la cubierta vegetal son una amenaza para la biota nativa y los fósiles. Por lo tanto, las medidas de conservación necesarias para proteger los fósiles tendrían múltiples beneficios para la ecología del área.
Abstract The Piedra Chamana Fossil Forest, near the village of Sexi in central Cajamarca, records the vegetation of the South American tropics 39 million years ago, early in the New World tropical forests history and before the rise of the present-day Andes. In this fossil forest, notable discoveries have included the mangrove genus Avicennia, a genus of emergent forest trees (Cynometra), and the second dipterocarp known from the New World. The significance of the fossils rests on the unique circumstances of preservation, the detailed reconstruction of the forest and environment that is possible based on the plant fossils and ancient soils, and the importance of this record for the study of climate change. Sites like the fossil forest are particularly vulnerable to disturbance and loss of the fossil resources. Ongoing monitoring shows that human activities and erosion are having serious effects and, conservation measures are urgently needed. The importance of the fossils for science, the beauty of this area of the Andes, and the potential of the site for education and tourism justify recognition of the fossil forest at an international level. The lowland tropical forest represented by the fossils is very different from the diverse broad-leaf sclerophyllous forest or woodland now growing in the area. Soil loss and erosion of the soft, porous volcanic substrate when the vegetation cover is disturbed poses a threat to both the native biota and the fossils. The conservation measures needed at the fossil site would have multiple benefits for the ecology of the region.
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In 1987 particularly, but also in 1988, primaeval montane coniferous forests of northern Scandinavia experienced needle loss on an unprecedented scale, which affected the character of the entire landscape in certain regions. This study elucidates the dieback event For Norway spruce [Picea abies (L.) Karst.] in an area of the Swedish Scandes. The study includes visual assessment of percentage needle loss, age structure, radial growth and various environmental parameters, along altitudinal transects and within a larger sample plot. Frequency and magnitude of foliage damage were found to be related to elevation. The dieback process of closed forest stands was interpreted as a response to short-term climatic variability. Damage mainly developed during one of the coldest early winters (December January 1986/7) of this century. In combination with sub-normal depth of the snow caver, the severe cold promoted exceptionally deep and persistent soil frost in spruce forest stands. It is hypothesized that damage was mainly due to winter/spring drought (frost-drought). Phenotypically closed forest stands may change in just a few years in response to cooling, a feature which has not been realized previously. The possibility of major retrogressive responses lo short-term climatic events should therefore be considered in studies of historical biogeography and when modelling vegetation succession. The forest studied was probably established after a severe wind storm in 1837. The restocking process was facilitated by the post-Little Ice Age warming, but the stands are at present suffering severe dieback due to the recent cooling of the climate. The results stress the potential importance of short-term climatic disturbance in boreal forest succession. Reasonably, rapid cold-induced dieback of forest stands may have been a recurrent feature of Holocene forest history in the Boreal zone.
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Forests in Europe have been shaped considerably by human activities during most of the Holocene. Changes in forest structure, distribution of tree species and forest biodiversity are partly driven by management history, and many current forest types result from former management. The interdisciplinary project "Long-term woodland dynamics in Central Europe: from estimations to a realistic model" (LONGWOOD) aims to reconstruct long-term dynamics of woodland cover, structure and management in the eastern Czech Republic (Moravia, ca. 27,000 km2), compare the historical and present state of forests, and analyze general patterns of changes and stability of woodlands as well as the role of humans in these processes. In the LONGWOOD project, palaeoecological, archaeological, historical and ecological sources of information on woodland cover, species composition, and human activities (management, settlement density) over the past 7500 years are collected and integrated in the form of a geodatabase. Combining data of different origin, scale, degree of spatial precision and detail into a single geodatabase is a challenging task. The level of detail, information content, and spatio-temporal distribution of data varies between layers as well as individual records according to the nature of the data source and the data itself. The limited and incomplete sources of information until ca. 1100 AD provide a coarser view on forest history while the historical period (especially the past ca. 250 years) is covered by large amounts of precisely located ecological and historical data enabling detailed spatial and temporal analyses. Data on forest structure, history and management will be related to environmental factors (soil type, climate, elevation and other topographic variables derived from DEM) and social historical data (settlement distribution, population density, landuse). A spatio-temporal forest landscape model will be built to assess the forest changes and the main drivers of change.