48 research outputs found
European agricultural landscapes, common agricultural policy and ecosystem services: a review
Since the 1950s, intensification and scale enlargement of agriculture have changed agricultural landscapes across Europe. The intensification and scale enlargement of farming was initially driven by the large-scale application of synthetic fertilizers, mechanization and subsidies of the European Common Agricultural Policy (CAP). Then, after the 1990s, a further intensification and scale enlargement, and land abandonment in less favored areas was caused by globalization of commodity markets and CAP reforms. The landscape changes during the past six decades have changed the flows and values of ecosystem services. Here, we have reviewed the literature on agricultural policies and management, landscape structure and composition, and the contribution of ecosystem services to regional competitiveness. The objective was to define an analytical framework to determine and assess ecosystem services at the landscape scale. In contrast to natural ecosystems, ecosystem service flows and values in agricultural landscapes are often a result of interactions between agricultural management and ecological structures. We describe how land management by farmers and other land managers relates to landscape structure and composition. We also examine the influence of commodity markets and policies on the behavior of land managers. Additionally, we studied the influence of consumer demand on flows and values of the ecosystem services that originate from the agricultural landscape
Newly resolved relationships in an early land plant lineage: Bryophyta class Sphagnopsida (peat mosses)
Premise of the study : The Sphagnopsida, an early-diverging lineage of mosses (phylum Bryophyta), are morphologically and
ecologically unique and have profound impacts on global climate. The Sphagnopsida are currently classifi ed in two genera,
Sphagnum (peat mosses) with some 350 – 500 species and Ambuchanania with one species. An analysis of phylogenetic relationships among species and genera in the Sphagnopsida were conducted to resolve major lineages and relationships among species within the Sphagnopsida. Methods : Phylogenetic analyses of nucleotide sequences from the nuclear, plastid, and mitochondrial genomes (11 704 nucleotides total) were conducted and analyzed using maximum likelihood and Bayesian inference employing seven different
substitution models of varying complexity.
Key results : Phylogenetic analyses resolved three lineages within the Sphagnopsida: (1) Sphagnum sericeum , (2) S. inretortum plus Ambuchanania leucobryoides , and (3) all remaining species of Sphagnum . Sister group relationships among these three clades could not be resolved, but the phylogenetic results indicate that the highly divergent morphology of A. leucobryoides is derived within the Sphagnopsida rather than plesiomorphic. A new classifi cation is proposed for class Sphagnopsida, with one order (Sphagnales), three families, and four genera.
Conclusions : The Sphagnopsida are an old lineage within the phylum Bryophyta, but the extant species of Sphagnum represent a relatively recent radiation. It is likely that additional species critical to understanding the evolution of peat mosses await discovery, especially in the southern hemisphere