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Abstract: Land-use intensification causes species losses reducing phylogenetic and functional trait diversity as well as ecosystem function. Phylogenetic (PD) and functional (FD) diversity of regional assemblages have been identified as a key to understanding ecosystem and community functioning, yet it has been rarely included in conservation planning. The use of indicator groups to represent species richness is by far the most common measure used for developing plans to conserve current and future biodiversity. Could indicator groups be used for representing PD and FD of whole assemblages? Using a continuous measure of PD and FD derived from phylogenies and quantitative functional traits of species and their functional relationships, we assessed the effectiveness of 16 indicator groups in representing these evolutionary and functional components of biodiversity to answer this question. We focused our analyses on the entire set of 854 bird species occurring in the Atlantic Forest Biodiversity Hotspot, as a case study. We show that a particular bird order (Apodiformes) is the most effective surrogate group to capture PD, while the Charadriiformes and restricted-range species are the most effective surrogate group to capture FD. Their use as a shortcut to conservation planning is likely to guarantee the conservation of evolutionary and ecosystem processes through the representation of the unique species, as well as ecosystem stability in the long term, with the representation of the redundant species. [Copyright &y& Elsevier]

Abstract: Changes from natural tree species to rapidly growing exotic species as well as intensification of forestry operations with heavy machinery can lead to changes in the quantity and quality of organic matter inputs to soil and to disruption of soil physical structure. These two ecosystem properties are tightly linked to organic matter dynamics. Five adjacent forest stands were selected to study soil organic matter dynamics in soil physical fractions. On one hand, two semi-natural broadleaved forests (Quercus robur, Fagus sylvatica) and an adult radiata pine plantation (40-year-old,) in order to study the effect of species change on these parameters, and on the other, a chronosequence of Pinus radiata plantations (40-year-old; 3-year-old; 16-year-old), to study the effect of mechanization during harvesting and intense site preparation. Samples of intact topsoil (0–5 cm) were collected and aggregate-size distribution, mean weight diameter (MWD), total C and N, particulate organic matter (POM)-C, POM-N and microbial biomass-C were determined in each aggregate size fraction. Microbial respiration and nitrogen mineralization were also assessed in each aggregate size fraction, during a 28 day incubation period. Losses of POM-C and POM-N in the bulk soil due to mechanical site preparation were high relative to total soil C and N, which suggests that POM is a sensitive parameter to the effect of mechanization. The ratio C-POM:SOM was significantly related to MWD (R 2 = 0.75, P < 0.001) reflecting that POM may play a key role in the topsoil aggregate formation in these stands. Semi-natural stands had a higher proportion of macroaggregates (0.25–2 mm) than the cultivated adult one. Megaaggregates (>2 mm) were the most abundant class in mature stands (82–92%), whereas macro- and microaggregates (<2 mm) were the most abundant ones in the intensely soil prepared P. radiata plantation (49%). Indicators for sustainable forest management related to soil organic matter should not only be assessed in terms of total C stocks but also with respect to sensitive organic matter and its degradability in different size classes. [Copyright &y& Elsevier]