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Radioactive contamination of agricultural land may necessitate long-term changes in food production systems, through application
of selected countermeasures, in order to reduce the accumulation of radionuclides in food. We quantified the impact of selected
countermeasures on habitat diversity, using the hypothetical case of two agricultural areas in Finland. The management scenarios
studied were conversions from grassland to cereal production and from grassland and crop production to afforestation. The
two study sites differed with respect to present agricultural production: one being predominantly cereal production and seminatural
grasslands, while the other was dominated by intensive grass and dairy production. Some of the management scenarios are expected
to affect landscape structures and habitat diversity. These potential changes were assessed using a spatial pattern analysis
program in connection with geographic information systems. The studied landscape changes resulted in a more monotonous landscape
structure compared to the present management, by increasing the mean habitat patch size, reducing the total habitat edge length
and reducing the overall habitat diversity calculated by the Shannon diversity index. The degree of change was dependent on
the present agricultural management practice in the case study sites. Where dairy production was predominant, the landscape
structure changes were mostly due to conversion of intensive pastures and grasslands to cereal production. In the area dominated
by cereal production and seminatural grasslands, the greatest predicted impacts resulted from afforestation of meadows and
pastures. The studied management changes are predicted to reduce biodiversity at the species level as well as diminishing
species-rich habitats. This study has predicted prominent side effects in habitat diversity resulting from application of
management scenarios. These potential long-term impacts should be considered by decision-makers when planning future strategies
in the event of radionuclide deposition. 相似文献
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Laura Bouriaud Mariella Marzano Manfred Lexer Liviu Nichiforel Christopher Reyer Christian Temperli Heli Peltola Ché Elkin Gabriel Duduman Philip Taylor Stephen Bathgate Jose G. Borges Sandra Clerkx Jordi Garcia-Gonzalo Carlos Gracia Geerten Hengeveld Seppo Kellomäki Georgi Kostov Michael Maroschek Bart Muys Gert-Jan Nabuurs Bruce Nicoll Marc Palahí Werner Rammer Duncan Ray Mart-Jan Schelhaas Louise Sing Margarida Tomé Juergen Zell Marc Hanewinkel 《Regional Environmental Change》2015,15(8):1595-1609
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与芬兰农业变化有关的草地中植物种类丰富度和生境连通度的降低 总被引:9,自引:0,他引:9
Miska Luoto Seppo Rekolainen Jyrki Aakkula Juha Pykl 《Ambio-人类环境杂志》2003,32(7):447-452
20世纪中,欧洲半天然草地严重减少,物种多样性降低,这与社会-经济因素密切相关.农业生产的发展驱动着土地利用的变化,从而控制着景观维持生物多样性的能力.本研究中,我们把农业生产变化和景观破碎化、物种多样性联系在一起.结果表明,半天然草地的停止放牧引起了景观结构的显著变化,并使维管束植物种的数目降低.放牧草场数量的下降主要是受与农业政策措施有关的农场水平的经济效果和收益率的影响.自1995年芬兰加入欧盟以来,由于对半天然草地经营有了扶持政策,我们研究地区中放牧斑块的面积又一次增加了. 相似文献
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Antti Kilpeläinen Harri Strandman Seppo Kellomäki Jyri Seppälä 《Mitigation and Adaptation Strategies for Global Change》2014,19(7):955-968
The main objective of the study was to calculate net atmospheric impacts for wood production and utilization in Finnish boreal forest conditions. Net atmospheric impacts were calculated by comparing net CO2 exchanges of the wood production and utilization to the reference management regime. Net CO2 exchanges were simulated with a life cycle assessment (LCA) tool for a Scots pine (Pinus sylvestris L.) stand (MT, Myrtillys-type) in central Finland (Joensuu region, 62°39 N, 29°37 E) over two consecutive rotation periods (100?+?100 years/200 years). Net atmospheric impacts were calculated both for sawn timber and pulpwood, and expressed in kgCO2m?3. According to the results, the production of pulp and sawn timber produced emissions of 0.20 and 0.59 kgCO2m?3 over the 200-year period, respectively, when the unmanagement regime was used as the reference management regime. When 50 % of the processing waste of timber was accounted as an instant emission to the atmosphere, the atmospheric impact increased to 0.55 kgCO2m?3 in pulpwood and to 1.27 kgCO2m?3 in sawn timber over the 200 year period. When turnover rates of sawn timber in the technosystem were decreased by 30 % and the share of energy use was decreased to 30 %, the atmospheric impact decreased by 17 % and 4 % for pulpwood and sawn timber, respectively, compared to the default wood degradation and energy use of 50 %. The utilized LCA approach provided an effective tool for approaching net atmospheric impacts originating from the ecosystem carbon (C) flows and variable wood utilization. Taking the ecosystem production and utilization of wood (i.e. degradation of technosystem C stock) into account, in terms of net CO2 exchange, the mitigation possibilities of wood compared to other products can be accounted for more precisely in the future and C sequestration credited more specifically for a certain wood product. 相似文献