Mikusiński Grzegorz, Angelstam Per, Sporrong Ulf
Swedish University of Agricultural Sciences.
Ambio. 2003 Dec;32(8):520-6. doi: 10.1579/0044-7447-32.8.520.
Termination of fire along with active removal of deciduous trees in favor of conifers together with anthropogenic transformation of productive forest into agricultural land, have transformed northern European coniferous forests and reduced their deciduous component. Locally, however, in the villages, deciduous trees and stands were maintained, and have more recently regenerated on abandoned agricultural land. We hypothesize that the present distribution of the deciduous component is related to the village in-field/out-field zonation in different regions, which emerges from physical conditions and recent economic development expressed as land-use change. We analyzed the spatial distribution of deciduous stands in in-field and out-field zones of villages in 6 boreal/hemiboreal Swedish regions (Norrbotten, Angermanland, Jämtland, Dalarna, Bergslagen, Småland). In each region 6 individual quadrates 5 x 5 km centered on village areas were selected. We found significant regional differences in the deciduous component (DEC) in different village zones. At the scale of villages Angermanland had the highest mean proportion of DEC (17%) and Jämtland the lowest (2%). However, the amounts of the DEC varied systematically in in-field and out-field zones. DEC was highest in the in-field in the south (Småland), but generally low further north. By contrast, the amount of DEC in the out-field was highest in the north. The relative amount of DEC in the forest edge peaked in landscapes with the strongest decline in active agriculture (Angermanland, Dalarna, Bergslagen). Because former and present local villages are vital for biodiversity linked to the deciduous component, our results indicate a need for integrated management of deciduous forest within entire landscapes. This study shows that simplified satellite data are useful for estimating the spatial distribution of deciduous trees and stands at the landscape scale. However, for detailed studies better thematic resolution is needed to determine biologically relevant differences in quality of deciduous stands.
火灾的终止以及为了针叶树而积极移除落叶树，再加上将生产性森林人为转变为农业用地，改变了北欧的针叶林并减少了其中的落叶成分。然而，在当地的村庄里，落叶树和林分得以保留，并且最近在废弃的农田上重新生长。我们推测，落叶成分的当前分布与不同地区村庄的田间/田外分区有关，这种分区源于物理条件以及以土地利用变化形式体现的近期经济发展。我们分析了瑞典6个北方/近北方地区（北博滕、昂厄曼兰、耶姆特兰、达拉纳、伯格斯拉根、斯莫兰）村庄的田间和田外区域落叶林分的空间分布。在每个地区，选择了6个以村庄区域为中心的5×5千米的独立样方。我们发现不同村庄区域的落叶成分（DEC）存在显著的区域差异。在村庄尺度上，昂厄曼兰的DEC平均比例最高（17%），耶姆特兰最低（2%）。然而，DEC的数量在田间和田外区域有系统的变化。DEC在南部（斯莫兰）的田间最高，但在更北的地区总体较低。相比之下，田外的DEC数量在北部最高。森林边缘的DEC相对数量在农业活动下降最强烈的景观中达到峰值（昂厄曼兰、达拉纳、伯格斯拉根）。由于过去和现在的当地村庄对于与落叶成分相关的生物多样性至关重要，我们的结果表明需要对整个景观中的落叶林进行综合管理。这项研究表明，简化的卫星数据对于估算景观尺度上落叶树和林分的空间分布是有用的。然而，对于详细研究，需要更好的专题分辨率来确定落叶林分质量上生物学相关的差异。
