Land and people

Our relationship with the landscape has developed through time and more and more the environment is responding to human-driven changes. Now is the time to steer this relationship towards a sustainable future, suggest our Editorial Board Members. Our relationship with the landscape has developed through time and more and more the environment is responding to human-driven changes. Now is the time to steer this relationship towards a sustainable future, suggest our Editorial Board Members

Effects of natural and experimental drought on soil fungi and biogeochemistry in an Amazon rain forest

Microbiota are essential components of the soil, driving biogeochemical cycles. Fungi affect decomposition and biotic interactions with plants across scales. Climate projections suggest that extended dry seasons may transform sensitive rain forests into savanna-like vegetation, with consequent changes in biogeochemistry. Here we compare the impacts of natural seasonality with 14 years of partial throughfall exclusion in an Amazonian rain forest, focussing on soil fungal functional diversity, extracellular soil enzyme activities (EEA) and their implications for nutrient dynamics. Large changes in fungal diversity and functional group composition occur in response to drought, with a conspicuous increase in the abundance of dark-septate fungi and a decrease in fungal pathogens. The high seasonality of EEA in the control (non droughted) and suppression of seasonality in the drought treatment, together with an increased implied nitrogen demand in the dry season induced by experimental drought, suggest that the changed soil microbiota activity may signal a pending shift in the biogeochemical functioning of the forest.R.C.S. was supported by grants received from the Brazilian National Research Council (CNPq; 383166/2015-2) and Higher Education Research Council.(CAPES; 1633282). J.G. received funding from the Lendület Program (96049) of the Hungarian Academy of Sciences and the Eötvös Lóránd Research Network. This work formed part of a project funded by the Natural Environment Research Council (NERC; NE/J011002/1, NE/N006852/1)

Spatio-temporal dynamics of soil bacterial communities as a function of Amazon forest phenology

Abstract Most tropical evergreen rain forests are characterised by varying degrees of precipitation seasonality that influence plant phenology and litterfall dynamics. Soil microbes are sensitive to soil water:air ratio and to nutrient availability. We studied if within-year seasonality in precipitation and litterfall-derived nutrient input resulted in predictable seasonal variation in soil bacterial diversity/microbial functional groups in an Amazonian forest. We characterised the spatio-temporal dynamics of microbial communities from the plot to the stand scales and related them to precipitation seasonality and spatial variability in soil characteristics. Community composition and functional diversity showed high spatial heterogeneity and was related to variability in soil chemistry at the stand level. Large species turnover characterised plot level changes over time, reflecting precipitation seasonality-related changes in soil nutrient and moisture regimes. The abundance of decomposers was highest during the rainy season, characterised also by anaerobic saprophytes and N2-fixers adapted to fluctuating redox conditions. In contrast, Beijerinckiaceae, likely derived from the phyllosphere, were found at higher abundances when litter inputs and accumulation were highest. We showed that in a mildly seasonal rain forest, the composition of soil microbial communities appears to be following canopy phenology patterns and the two are interlinked and drive soil nutrient availability

Ectomycorrhizal Plant-Fungal Co-invasions as Natural Experiments for Connecting Plant and Fungal Traits to Their Ecosystem Consequences

Introductions and invasions by fungi, especially pathogens and mycorrhizal fungi, are widespread and potentially highly consequential for native ecosystems, but may also offer opportunities for linking microbial traits to their ecosystem functions. In particular, treating ectomycorrhizal (EM) invasions, i.e., co-invasions by EM fungi and their EM host plants, as natural experiments may offer a powerful approach for testing how microbial traits influence ecosystem functions. Forests dominated by EM symbiosis have unique biogeochemistry whereby the secretions of EM plants and fungi affect carbon (C) and nutrient cycling; moreover, particular lineages of EM fungi have unique functional traits. EM invasions may therefore alter the biogeochemistry of the native ecosystems they invade, especially nitrogen (N) and C cycling. By identifying “response traits” that favor the success of fungi in introductions and invasions (e.g., spore dispersal and germination) and their correlations with “effect traits” (e.g., nutrient-cycling enzymes) that can alter N and C cycling (and affect other coupled elemental cycles), one may be able to predict the functional consequences for ecosystems of fungal invasions using biogeochemistry models that incorporate fungal traits. Here, we review what is already known about how EM fungal community composition, traits, and ecosystem functions differ between native and exotic populations, focusing on the example of EM fungi associated with species of Pinus introduced from the Northern into the Southern Hemisphere. We develop hypotheses on how effects of introduced and invasive EM fungi may depend on interactions between soil N availability in the exotic range and EM fungal traits. We discuss how such hypotheses could be tested by utilizing Pinus introductions and invasions as a model system, especially when combined with controlled laboratory experiments. Finally, we illustrate how ecosystem modeling can be used to link fungal traits to their consequences for ecosystem N and C cycling in the context of biological invasions, and we highlight exciting avenues for future directions in understanding EM invasion.Fil: Hoeksema, Jason D.. University of Mississippi; Estados UnidosFil: Averill, Colin. No especifíca;Fil: Bhatnagar, Jennifer M.. Boston University; Estados UnidosFil: Brzostek, Edward. West Virginia University; Estados UnidosFil: Buscardo, Erika. Universidade do Brasília; BrasilFil: Chen, Ko Hsuan. University of Florida; Estados UnidosFil: Liao, Hui Ling. University of Florida; Estados UnidosFil: Nagy, Laszlo. Universidade Estadual de Campinas; BrasilFil: Policelli, Nahuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; ArgentinaFil: Ridgeway, Joanna. West Virginia University; Estados UnidosFil: Rojas, J. Alejandro. University of Arkansas for Medical Sciences; Estados UnidosFil: Vilgalys, Rytas. University of Duke; Estados Unido

The PREDICTS database: a global database of how local terrestrial biodiversity responds to human impacts

Biodiversity continues to decline in the face of increasing anthropogenic pressures such as habitat destruction, exploitation, pollution and introduction of alien species. Existing global databases of species’ threat status or population time series are dominated by charismatic species. The collation of datasets with broad taxonomic and biogeographic extents, and that support computation of a range of biodiversity indicators, is necessary to enable better understanding of historical declines and to project – and avert – future declines. We describe and assess a new database of more than 1.6 million samples from 78 countries representing over 28,000 species, collated from existing spatial comparisons of local-scale biodiversity exposed to different intensities and types of anthropogenic pressures, from terrestrial sites around the world. The database contains measurements taken in 208 (of 814) ecoregions, 13 (of 14) biomes, 25 (of 35) biodiversity hotspots and 16 (of 17) megadiverse countries. The database contains more than 1% of the total number of all species described, and more than 1% of the described species within many taxonomic groups – including flowering plants, gymnosperms, birds, mammals, reptiles, amphibians, beetles, lepidopterans and hymenopterans. The dataset, which is still being added to, is therefore already considerably larger and more representative than those used by previous quantitative models of biodiversity trends and responses. The database is being assembled as part of the PREDICTS project (Projecting Responses of Ecological Diversity In Changing Terrestrial Systems – www.predicts.org.uk). We make site-level summary data available alongside this article. The full database will be publicly available in 2015

The effects of afforestation on biodiversity of grasslands in Ireland

Mestrado em Recursos Florestais e Ambiente, especialidade em Ecologia Florestal, Departamento de Engenharia Civil da Faculdade de Ciencias e Tecnologia da Universidade de Coimbra, 200

Ectomycorrhizal communities in fire prone environments: essential partners for pinetrees re-establishment

Las asociaciones mutualistas ectomicorrícicas (ECM) entre hongos y plantas superiores son un componente esencial de la mayoría de las comunidades vegetales y desempeñan un papel fundamental en los ciclos de nutrientes y en el funcionamiento de los ecosistemas. Los hongos ECM, y en particular, el banco de esporas y otros propágulos resistentes, están implicados también en los procesos de sucesión secundaria que facilitan la regeneración de las comunidades después de una perturbación. Especies ectomicorrícicas obligadas de ecosistemas mediterráneos propensos al fuego, como Pinus spp., muestran una gran dependencia de la presencia de inóculo fúngico para su regeneración después de un incendio. El efecto del fuego en las comunidades de hongos ECM varía dependiendo de las características del incendio y de las condiciones anteriores a la perturbación. En general, la composición de la comunidad ECM post-incendio es muy parecida a la del banco de esporas existente antes de la perturbación. Esto parece deberse a la supervivencia de esporas de hongos típicos de etapas tempranas de la sucesión, pero hay otros factores, que serán repasados en esta revisión, que pueden influir en la estructura y composición de la comunidad ECM y, por tanto, en el desarrollo de las plántulas del pinar de regeneración.Ectomycorrhizal (ECM) mutualistic associations between plants and fungi are obligatory component of most plant communities and play an important role in nutrient cycling and ecosystem functioning. ECM fungi, and in particular spore bank and other resistant propagules, are also involved in succession processes facilitating regeneration following disturbance events. Obligate ECM species in Mediterranean fire prone environments, in particular pine forests, are highly dependent on the presence of fungal inoculum for a successful succession establishment after fire events. ECM fungal communities can be affected by fires in different ways depending on fire characteristics and on pre-disturbance ecosystem conditions. Generally, the ECM community composition has a strong resemblance to the composition of the pre-fire spore bank community. This appears to be caused by survival of the soil spore bank of typical early-stage fungi, but other factors, which will be consider here, can shape the ECM community and thus the performance of pine seedlings.Este trabajo ha sido posible gracias a la beca predoctoral concedida a Erika Buscardo (SFRH/BD/21730/2005) por la FCT (“Fundação para a Ciência e a Tecnologia”) del “Ministerio de Ciencia, Tecnologia e Ensino Superior” de Portugal