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Effects of Land Use Changes on the Landscape Composition: A Comparison Between Finnish and Russian Karelia 总被引:1,自引:0,他引:1
Kimmo Saarinen Juha Jantunen Sanna Saarnio Karri Kuitunen Olli Marttila 《Environment, Development and Sustainability》2001,3(4):265-274
During the last 50 years the practising and intensity of agriculture and forestry have differed considerably between Finnish and Russian Karelia. We studied the effects of different land use practices on the landscape composition in the two countries using the road transect sampling along four study routes (99-121 km) between 1997 and 1999. Effective environmental management in Finland has resulted in more distinct agricultural land types, more even distribution of the different age classes of forests, and the higher abundance of coniferous forests. Fields (mean percentage of the landscape: Finland 28%, Russia 13%), clearcuts and sapling stands (15%, 6%), and young forests (23%, 9%) were more typical elements of the Finnish landscape, whereas settlements (9%, 13%), semi-natural grasslands (3%, 7%), and mature forests (20%, 49%) were more characteristic of the Russian landscape. Landscape-level differences between the two countries may have various effects on the diversity of fauna and flora inhabiting Finnish and Russian Karelia. 相似文献
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Peltonen-Sainio Pirjo Jauhiainen Lauri Palosuo Taru Hakala Kaija Ruosteenoja Kimmo 《Regional Environmental Change》2016,16(5):1521-1533
Regional Environmental Change - Global warming is likely to prolong the growing season at high latitudes where the brevity of the growing season currently limits crop growth and yields. A longer... 相似文献
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Prior residency as a key determinant of social dominance in the willow tit (Parus montanus) 总被引:1,自引:0,他引:1
Kari Koivula Kimmo Lahti Markku Orell Seppo Rytkönen 《Behavioral ecology and sociobiology》1993,33(4):283-287
Summary We studied how age, body size and prior residency affected social dominance in the willow tit (Parus montanus) groups. The contribution of each variable was experimentally tested in unisexual two-bird trials, in which the birds were matched for all variables except the one studied. Large birds were dominant over smaller ones (Fig. 1). The effect of body size was more prominent in males than in females. Age had no influence on dominance. Residents became dominant more often than newcomers (Fig. 2). Adulthood or larger body size did not override the advantage of prior residency (Fig. 2). Therefore, the proximate reason for the age-dependent dominance seen in natural willow tit flocks is most likely the prior residency advantage of the adults. Factors connected with fighting ability (body size and age) seem to be less important than the time of establishment of rank, which may reflect the importance of resource value differences between residents and newcomers in this context. The advantage of residency might make it advantageous to be a member of a flock even as a subordinate, rather than being solitary. 相似文献