Current issue: 54(2)
Under compilation: 54(3)
Environmental planning for of the maintenance of different conservation objectives should take into account multiple contrasting criteria based on alternative uses of the landscape. We develop new concepts and approaches to describe and measure conflicts among conservation objectives and for resolving them via multiobjective optimization. To measure conflicts we introduce a compatibility index that quantifies how much targeting a certain conservation objective affects the capacity of the landscape for providing another objective. To resolve such conflicts we find compromise solutions defined in terms of minimax regret, i.e. minimizing the maximum percentage of deterioration among conservation objectives. Finally, we apply our approach for a case study of management for biodiversity conservation and development in a forest landscape. We study conflicts between six different forest species, and we identify management solutions for simultaneously maintaining multiple species’ habitat while obtaining timber harvest revenues. We employ the method for resolving conflicts at a large landscape level across a long 50-years forest planning horizon. Our multiobjective approach can be an instrument for guiding hard choices in the conservation-development nexus with a perspective of developing decision support tools for land use planning. In our case study multiple use management and careful landscape level planning using our approach can reduce conflicts among biodiversity objectives and offer room for synergies in forest ecosystems.
Populations at species’ range margins are expected to show lower genetic diversity than populations at the core of the range. Yet, long-lived, widespread tree species are expected to be resistant to genetic impoverishment, thus showing comparatively high genetic diversity within populations and low differentiation among populations. Here, we study the distribution of genetic variation in the pedunculate oak (Quercus robur L.) at its range margin in Finland at two hierarchical scales using 15 microsatellite loci. At a regional scale, we compared variation within versus among three oak populations. At a landscape scale, we examined genetic structuring within one of these populations, growing on an island of ca 5 km2. As expected, we found the majority of genetic variation in Q. robur to occur within populations. Nonetheless, differentiation among populations was markedly high (FST = 0.12) compared with values reported for populations of Q. robur closer to the core of its range. At the landscape level, some spatial and temporal sub-structuring was observed, likely explained by the history of land-use on the island. Overall, Q. robur fulfils the expectation of the central-marginal hypothesis of high differentiation among marginal populations, but the notable population differentiation has most likely been influenced also by the long, ongoing fragmentation of populations. Finnish oak populations may still be adjusting to the drastic habitat changes of the past centuries. Preservation of genetic variation within the remaining stands is thus an important factor in the conservation of Q. robur at its range margin.