The management of landscapes for biological conservation and ecologically sustainable natural resource use are crucial global issues. Research for over two decades has resulted in a large literature, yet there is little consensus on the applicability or even the existence of general principles or broad considerations that could guide landscape conservation. We assess six major themes in the ecology and conservation of landscapes. We identify 13 important issues that need to be considered in developing approaches to landscape conservation. They include recognizing the importance of landscape mosaics (including the integration of terrestrial and aquatic areas), recognizing interactions between vegetation cover and vegetation configuration, using an appropriate landscape conceptual model, maintaining the capacity to recover from disturbance and managing landscapes in an adaptive framework. These considerations are influenced by landscape context, species assemblages and management goals and do not translate directly into on-the-ground management guidelines but they should be recognized by researchers and resource managers when developing guidelines for specific cases. Two crucial overarching issues are: (i) a clearly articulated vision for landscape conservation and (ii) quantifiable objectives that offer unambiguous signposts for measuring progress.

The concept of habitat fragmentation has become an important theme in conservation research, and it is often used as if fragmentation were a unitary phenomenon. However, the concept is ambiguous, and empirical studies demonstrate a wide variety of direct and indirect effects, sometimes with mutually opposing implications. The effects of fragmentation vary across organisms, habitat types, and geographic regions. Such a contrast between a schematic concept and multifaceted empirical reality is counterproductive. I analyzed the stabilization of the schematic view of fragmentation by the early 1980s, using a genealogical narrative as a methodological approach. The main assumptions behind the schematic view were: (1) fragments are comparable to oceanic islands; (2) habitats surrounding fragments are hostile to a majority of the organisms; and (3) natural pre-fragmentation conditions were uniform. The stabilization loop of this view was supported by the reduction of empirical research to species-area curve fitting, which always produced expected results. I present a model of the dynamics of fragmentation research that shows the schematic, island-biogeographic view as an ''intellectual attractor.'' Since the 1980s, the theoretical presuppositions of the schematic view have been challenged, and empirical research has become multifaceted. Fragments of a particular habitat type are viewed as elements in a heterogeneous landscape rather than ''islands'' surrounded by a hostile ''sea.'' However, the island metaphor is still used in conservation contexts in the shape of speciesarea curves. It is backed by a presupposition that human-influenced environments are essentially different from so-called ''natural'' environments, but this is unfounded. My suggestion is that our perspective should be broadened still further so that habitat fragmentation is viewed as a particular form of human-induced environmental degradation; I discuss both theoretical and practical implications of this suggestion.Instead of an essentially continuous forest cover, with infrequent meadow-like openings along watercourses or small grasslands where fires had been unusually severe, the landscape now presents the aspect of a savana, with isolated trees, small clumps or clusters of trees, or small groves scattered in a matrix of artificial grassland of grains and pasture grasses, unstable and frequently devoid of plant cover as a result of regular plowing.

The concept of habitat fragmentation has become an important theme in conservation research, and it is often used as if fragmentation were a unitary phenomenon. However, the concept is ambiguous, and empirical studies demonstrate a wide variety of direct and indirect effects, sometimes with mutually opposing implications. The effects of fragmentation vary across organisms, habitat types, and geographic regions. Such a contrast between a schematic concept and multifaceted empirical reality is counterproductive. I analyzed the stabilization of the schematic view of fragmentation by the early 1980s, using a genealogical narrative as a methodological approach. The main assumptions behind the schematic view were: (1) fragments are comparable to oceanic islands; (2) habitats surrounding fragments are hostile to a majority of the organisms; and (3) natural pre‐fragmentation conditions were uniform. The stabilization loop of this view was supported by the reduction of empirical research to species–area curve fitting, which always produced expected results. I present a model of the dynamics of fragmentation research that shows the schematic, island‐biogeographic view as an “intellectual attractor.” Since the 1980s, the theoretical presuppositions of the schematic view have been challenged, and empirical research has become multifaceted. Fragments of a particular habitat type are viewed as elements in a heterogeneous landscape rather than “islands” surrounded by a hostile “sea.” However, the island metaphor is still used in conservation contexts in the shape of species–area curves. It is backed by a presupposition that human‐influenced environments are essentially different from so‐called “natural” environments, but this is unfounded. My suggestion is that our perspective should be broadened still further so that habitat fragmentation is viewed as a particular form of human‐induced environmental degradation; I discuss both theoretical and practical implications of this suggestion.

Management practices favoring conifers at the expense of deciduous tree species, and the eradication of deciduous trees, especially aspen Populus tremula, from managed forests have resulted in population declines in several species in Fennoscandia. ln addition to species depending on decaying wood of deciduous trees, earlier evidence suggests that leaf litter, especially that of aspen, is favored by many carabid species. We ran a four-year experiment in order to compare carabid assemblages of unchanged forest floor with artificially created leaf-litter plots in central Finland. A total of 18 plots (5 m in diameter) were established in three forest stands without aspen a few kilometers apart. Each stand had 3 litter plots (litter added) and 3 control plots. Pre-treatment samples were compared with those collected after litter addition. The litter addition affected the carabid-assemblage structure by increasing the catches of some species and decreasing the catch of one species. The number of carabid species was similar in control and litter plots. The litter elfect was smaller than variation among forest stands and year-to-year fluctuations. There was a strong temporal constancy among the plots: "rich" plots remained "rich" from year to year and similarly. "poor" plots remained "poor".The significant influence of leaf litter on carabid abundance can be attributable to both abiotic factors (microenvironmental conditions, especially humidity and temperature), and biotic ones (changes in niche structure, improved food supply). Leaf litter seems to have an effect on carabid distribution patterns, and deciduous trees scattered among conifers are likely to be of importance on carabid fauna in boreal IOrests.M. Koiuula (mkoiuula@cc.helsinki.fi) and J. Niemeki,