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Anssi Paasi 《GeoJournal》1997,43(1):41-50
National identity has become a catchword in discussions of the relations between culture and nation-states during recent decades. Narratives of nation have become crucial in the definition of the individual, so that other identities are usually understood only as slightly modifying it. The present paper starts from the fact that nation, national identity and nationalism are contextual and co ntested categories, and suggests a critical approach, labelled as the institutionalization of territories, which should evaluate the practices and ideological mechanisms involved in the production and reproduction of territories and their identities. The institutionalization of the Finnish territory and the representations of Finnish national identity are analysed as concrete examples. It is argued that national identities develop and change continually, so that each generation modifies it according to existing socio-cultural situations. Certain critical historical periods and specific natural and cultural elements seem to be crucial in the narration of Finnish identity. 相似文献
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Hannu Marttila Annalea Lohila Pertti Ala-Aho Kashif Noor Jeffrey M. Welker Danny Croghan Kaisa Mustonen Leo-Juhani Meriö Anna Autio Filip Muhic Hannah Bailey Mika Aurela Jussi Vuorenmaa Timo Penttilä Valtteri Hyöky Eric Klein Anton Kuzmin Pasi Korpelainen Timo Kumpula Anssi Rauhala Bjørn Kløve 《水文研究》2021,35(9):e14350
Subarctic ecohydrological processes are changing rapidly, but detailed and integrated ecohydrological investigations are not as widespread as necessary. We introduce an integrated research catchment site (Pallas) for atmosphere, ecosystems, and ecohydrology studies in subarctic conditions in Finland that can be used for a new set of comparative catchment investigations. The Pallas site provides unique observational data and high-intensity field measurement datasets over long periods. The infrastructure for atmosphere- to landscape-scale research in ecosystem processes in a subarctic landscape has recently been complemented with detailed ecohydrological measurements. We identify three dominant processes in subarctic ecohydrology: (a) strong seasonality drives ecohydrological regimes, (b) limited dynamic storage causes rapid stream response to water inputs (snowmelt and intensive storms), and (c) hydrological state of the system regulates catchment-scale dissolved carbon dynamics and greenhouse (GHG) fluxes. Surface water and groundwater interactions play an important role in regulating catchment-scale carbon balances and ecosystem respiration within subarctic peatlands, particularly their spatial variability in the landscape. Based on our observations from Pallas, we highlight key research gaps in subarctic ecohydrology and propose several ways forward. We also demonstrate that the Pallas catchment meets the need for sustaining and pushing the boundaries of critical long-term integrated ecohydrological research in high-latitude environments. 相似文献
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Anssi Pekkarinen Lucia Reithmaier Peter Strobl 《ISPRS Journal of Photogrammetry and Remote Sensing》2009,64(2):171-183
This paper describes a simple and adaptive methodology for large area forest/non-forest mapping using Landsat ETM+ imagery and CORINE Land Cover 2000. The methodology is based on scene-by-scene analysis and supervised classification. The fully automated processing chain consists of several phases, including image segmentation, clustering, adaptive spectral representativity analysis, training data extraction and nearest-neighbour classification. This method was used to produce a European forest/non-forest map through the processing of 415 Landsat ETM+ scenes. The resulting forest/non-forest map was validated with three independent data sets. The results show that the map’s overall point-level agreement with our validation data generally exceeds 80%, and approaches 90% in central European conditions. Comparison with country-level forest area statistics shows that in most cases the difference between the forest proportion of the derived map and that computed from the published forest area statistics is below 5%. 相似文献
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Jarmo J. Meriläinen Juhani Hynynen Arja Palomäki Pasi Reinikainen Anssi Teppo Kaj Granberg 《Journal of Paleolimnology》2000,24(3):251-270
The recent environmental history of Lake Lappajärvi in western Finland (63°00 N, 23°30 E, area 149 km2), a humic, brown water lake with an average phosphorus content of ca. 20 g l–1, was studied from short core sediment samples taken from the two main basins of the lake. Based on the stratigraphy of diatoms and chironomids and the sediment quality it was possible to distinguish four developmental stages during the past century: (1) a pre-industrial stage covering the time up to about 1935; (2) a stage of increasing nutrient loading (ca. 1936–1960); (3) a stage of pronounced erosion from lake level regulation and extensive ditching of the catchment area (ca. 1960–1970); and (4) a meso-eutrophic stage from ca. 1970 onwards.Acidophilous Aulacoseira distans coll. and other species typical of dystrophic, nutrient-poor lakes characterized the diatom assemblages during the first stage, and the profundal zoobenthic assemblages, characterized by Heterotrissocladius subpilosus and Micropsectra, indicated good hypolimnetic oxygen conditions and a low sedimentation of organic matter (approx. less than 50 g m–2 a–1). The increased loading rapidly led to changes both in diatoms and chironomids (e.g., to an early extinction of H. subpilosus in the 1950s). The process finally led to eutrophication with a successive proliferation of diatom species such as Asterionella formosa followed by Aulacoseira ambigua, Fragilaria crotonensis, and finally Melosira varians. The relative proportion of alkaliphilous species reached a maximum in the final stage and the original profundal chironomid fauna was replaced by Chironomus anthracinus gr. and C. plumosus which are typical of profundal areas suffering from temporal oxygen deficit. It is notable that the considerable decrease in waste water loading from the point sources (80–86% ) during the past two decades has not led to a recovery in the lake. This highlights the importance of diffuse loading from agriculture, forestry and other human activities even to this comparatively large lake. 相似文献
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Anna Suuronen Anssi Lensu Markku Kuitunen Rodrigo Andrade-Alvear Natalia Guajardo Celis Marcelo Miranda Marcelo Perez Jussi V. K. Kukkonen 《Environmental Earth Sciences》2017,76(24):824
The optimization of photovoltaic solar power plants location in Atacama Desert, Chile, is presented in this study. The study considers three objectives: (1) Find sites with the highest solar energy potential, (2) determine sites with the least impact on the environment, and (3) locate the areas which produce small social impact. To solve this task, multi-criteria decision analyses (MCDAs) such as analytical hierarchy process and ordered weighted averaging were applied in a GIS environment. In addition, survey results of social impacts were analyzed and included into the decision-making process, including landscape values. The most suitable sites for solar energy projects were found near roads and power lines throughout the study area. Large suitable areas were found also from central valley from Arica and Parinacota to the north edge of Atacama region. In Atacama region, most suitable sites were found in the Andes. On the contrary, Andes were also found to have high environmental values and scenically valuable landscapes. Moderate and low suitability were found on the coast, especially in Atacama region. Factors such as slope and distance to power lines and roads influenced largely the sensitivity analysis. Area of high suitability increased by 15% when distance to roads was excluded and 18% when distance to power lines or slope was removed. MCDA-GIS method was found to be useful and applicable to the optimization of solar power plant locations in northern Chile. 相似文献
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