Compositional shifts of alpine plant communities across the high Andes.

Aim: Climate change is transforming mountain summit plant communities worldwide, but we know little about such changes in the High Andes. Understanding large-scale patterns of vegetation changes across the Andes, and the factors driving these changes, is fundamental to predicting the effects of global warming. We assessed trends in vegetation cover, species richness (SR) and community-level thermal niches (CTN) and tested whether they are explained by summits' climatic conditions and soil temperature trends. Location: High Andes. Time period: Between 2011/2012 and 2017/2019. Major taxa studied: Vascular plants. Methods: Using permanent vegetation plots placed on 45 mountain summits and soil temperature loggers situated along a ~6800 km N-S gradient, we measured species and their relative percentage cover and estimated CTN in two surveys (intervals between 5 and 8 years). We then estimated the annual rate of changes for the three variables and used generalized linear models to assess their relationship with annual precipitation, the minimum air temperatures of each summit and rates of change in the locally recorded soil temperatures. Results: Over time, there was an average loss of vegetation cover (mean = −0.26%/ yr), and a gain in SR across summits (mean = 0.38 species m2/yr), but most summits had significant increases in SR and vegetation cover. Changes in SR were positively related to minimum air temperature and soil temperature rate of change. Most plant communities experienced shifts in their composition by including greater abundances of species with broader thermal niches and higher optima. However, the measured changes in soil temperature did not explain the observed changes in CTN. Main conclusions: High Andean vegetation is changing in cover and SR and is shifting towards species with wider thermal niche breadths. The weak relationship with soil temperature trends could have resulted from the short study period that only marginally captures changes in vegetation through time.EEA Santa CruzFil: Cuesta, F. Universidad de las Américas. Grupo de Investigación en Biodiversidad Medio Ambiente y Salud – BIOMAS; Ecuador.Fil: Carilla, Julieta. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina.Fil: Carilla, Julieta. Universidad Nacional de Tucumán. Instituto de Ecología Regional; Argentina.Fil: Llambí, L.D. Universidad de Los Andes. Instituto de Ciencias Ambientales y Ecológicas; Venezuela.Fil: Llambí, L.D. Consorcio para el Desarrollo Sostenible de la Ecorregión Andina (CONDESAN); Perú.Fil: Muriel, P. Pontificia Universidad Católica del Ecuador. Escuela de Ciencias Biológicas Laboratorio de Ecofisiología; Ecuador.Fil: Lencinas, María Vanessa. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Austral de Investigaciones Científicas (CADIC); Argentina.Fil: Meneses, R. I. Universidad Católica del Norte. Instituto de Investigaciones Arqueológicas y Museo; Chile.Fil: Feeley, K. J. University of Miami. Biology Department. Coral Gables; Estados UnidosFil: Pauli, H. Austrian Academy of Sciences. Institute for Interdisciplinary Mountain Research; Austria.Fil: Pauli, H. University of Natural Resources and Life Sciences. Department of Integrative Biology and Biodiversity Research; Austria.Fil: Aguirre, N. Universidad Nacional de Loja. Carrera de Ingeniería Forestal. Centro de Investigaciones Tropicales del Ambiente y Biodiversidad (CITAB); Ecuador.Fil: Beck, S. Museo Nacional de Historia Natural - Instituto de Ecología (UMSA). Herbario Nacional de Bolivia; Bolivia.Fil: Peri, Pablo Luis. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Santa Cruz; Argentina.Fil: Peri, Pablo Luis. Universidad Nacional de la Patagonia Austral; Argentina.Fil: Peri, Pablo Luis. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina.Fil: Tovar, C. Royal Botanical Gardens Kew. Jodrell Laboratory; Reino Unid

Phenotypic biomarkers of climatic impacts on declining insect populations : A key role for decadal drought, thermal buffering and amplification effects and host plant dynamics

Widespread population declines have been reported for diverse Mediterranean butterflies over the last three decades, and have been significantly associated with increased global change impacts. The specific landscape and climatic drivers of these declines remain uncertain for most declining species. Here, we analyse whether plastic phenotypic traits of a model butterfly species (Pieris napi) perform as reliable biomarkers of vulnerability to extreme temperature impacts in natural populations, showing contrasting trends in thermally exposed and thermally buffered populations. We also examine whether improved descriptions of thermal exposure of insect populations can be achieved by combining multiple information sources (i.e., integrating measurements of habitat thermal buffering, habitat thermal amplification, host plant transpiration, and experimental assessments of thermal death time (TDT), thermal avoidance behaviour (TAB) and thermally induced trait plasticity). These integrative analyses are conducted in two demographically declining and two non-declining populations of P. napi

Ecological assessment of the mine La Colosa located in the forest reserve zone in Cajamarca Colombia

The pollution produced by mining causes environmental impacts on water, soil, wildlife, vegetation resources and serious damage to human life. The main purpose of this thesis is to study the transformation of the territory due to the mining project La Colosa using indicators to describe the situation

Landscape-scale population dynamics: field observations and modelling of Puya hamata, a flagship plant from the Andes

Important ecological processes happen over long periods of time and at the landscape scale. Effective conservation of biodiversity and management of natural resources and ecosystem services requires an understanding of these processes. Unfortunately, it is often impractical to conduct appropriate long-term, landscape-scale studies. Modelling offers an alternative approach. Complete ecosystems are too complex to model practically, but simulations of simplified systems provide useful insights of practical value. LandBaSE-P is an individual-based model for Puya hamata that provides information about impacts of fire on ecological processes in the páramo of the Reserva Ecológica El Ángel, Ecuador. Puya hamata is a flagship plant affected by fires and plays a key role in a number of ecological processes. This research found Puya hamata germinated much more frequently after fires, can form large aggregations of single recruitment cohorts, suffers very low mortality (with and without fires) once established, and lives up to 28 years. The spatial aggregation of Puya hamata plants reduced effective reproductive output, consistent with the theory that pollinator behaviour around large groups of Puya plants reduces cross-pollination, leading to inbreeding depression and poorer seed viability and germination. Puya hamata’s population structure can be an indicator of recent fire regime. LandBaSE-P simulations showed that population size is not affected by rare, long-distance seed dispersal. However, in the simulations of páramo grasslands, Puya relative germination is maintained in high numbers by burning. Puya hamata has an important role in ecology and biodiversity. The model LandBaSE-P is a complementary tool for conservation and sustainable land management. This thesis shows how fieldwork combined with laboratory studies and modelling, can provide a good understanding of complex dynamics of real-world populations, and generate ideas for management and future research.Consejo Nacional de Ciencia y Tecnología (CONACyT

Holocene Precipitation Variability, Prehistoric Agriculture, and Natural and Human-Set Fires in Costa Rica

This dissertation presents the results of compound-specific stable hydrogen isotope analysis of n-alkanes from terrestrial leaf waxes preserved in sediment cores from three lakes in Costa Rica to reconstruct variations in paleohydrology during the Holocene. Results were compared with pollen and charcoal data from the same cores to examine relationships between paleohydrology, vegetation change, prehistoric agriculture, and fire, and with archaeological evidence in the watersheds of two lakes to better understand prehistoric human-environment interactions. Lago de las Morrenas 1 (9.4925 °N, 83.4848 °W, 3480 m) is in the Chirripó páramo of Costa Rica, which was never permanently occupied by prehistoric people. The analyses demonstrate 10,000 years of millennial-scale variations in hydroclimate at Morrenas 1, which was dry during the Early Holocene, mesic during the Middle Holocene, and dry over the Late Holocene. The Morrenas sediments record local manifestations of the 8200 BP event, the 5200 BP event, the Terminal Classic Drought (TCD), and the Little Ice Age (LIA). Laguna Bonillita (9.9921 °N, 83.6114 °W, 450 m), in the Caribbean lowlands of central Costa Rica, has a 2700-year history of continuous maize agriculture. The alkane data show variations in paleohydrology over the Late Holocene and local manifestations of the TCD and the LIA that match patterns throughout the circum-Caribbean. The Bonillita watershed was intensively farmed across the entire history of the lake. Changes in prehistoric culture and maize farming are temporally linked to climate change at Bonillita. The data indicate that maize agriculture benefitted from episodes of drier climate in this lowland rainforest environment. Laguna Santa Elena (8.9290 °N, 82.9257 °W, 1055 m), in the Diquís archaeological subregion of southern Pacific Costa Rica, has a 2000-year history of maize agriculture. The analyses document variations in Late Holocene paleohydrology, including local manifestations of the TCD and the LIA, that had important consequences for prehistoric people. Santa Elena may have experienced a decrease in rainfall during the TCD, but unlike the Caribbean side of the Isthmus, the amplitude of this drought event does not appear abnormal on centennial to millennial timescales. Two population collapses inferred to take place during dry periods instead happened during wet intervals at Santa Elena

A baseline appraisal of water-dependant ecosystem services, the roles they play within desakota livelihood systems and their potential sensitivity to climate change

This report forms part of a larger research programme on 'Reinterpreting the Urban-Rural Continuum', which conceptualises and investigates current knowledge and research gaps concerning 'the role that ecosystems services play in the livelihoods of the poor in regions undergoing rapid change'. The report aims to conduct a baseline appraisal of water-dependant ecosystem services, the roles they play within desakota livelihood systems and their potential sensitivity to climate change. The appraisal is conducted at three spatial scales: global, regional (four consortia areas), and meso scale (case studies within the four regions). At all three scales of analysis water resources form the interweaving theme because water provides a vital provisioning service for people, supports all other ecosystem processes and because water resources are forecast to be severely affected under climate change scenarios. This report, combined with an Endnote library of over 1100 scientific papers, provides an annotated bibliography of water-dependant ecosystem services, the roles they play within desakota livelihood systems and their potential sensitivity to climate change. After an introductory, section, Section 2 of the report defines water-related ecosystem services and how these are affected by human activities. Current knowledge and research gaps are then explored in relation to global scale climate and related hydrological changes (e.g. floods, droughts, flow regimes) (section 3). The report then discusses the impacts of climate changes on the ESPA regions, emphasising potential responses of biomes to the combined effects of climate change and human activities (particularly land use and management), and how these effects coupled with water store and flow regime manipulation by humans may affect the functioning of catchments and their ecosystem services (section 4). Finally, at the meso-scale, case studies are presented from within the ESPA regions to illustrate the close coupling of human activities and catchment performance in the context of environmental change (section 5). At the end of each section, research needs are identified and justified. These research needs are then amalgamated in section 6

Soil mycobiota in agroecosystem: influence of land use and management

The present work investigated the biodiversity of soil fungi of agricultural areas differently managed by means of new generation sequencing technologies – NGS. The main object of this research was the analysis of the fungal biota in the Colombian soils, especially that of the upper Andean agro-environment. The study area was located in the region of Boyacá between 2800 and 3200 m asl. and characterized by different form of soil appropriation (apple and peach orchards, 10-year-old wood, and uncultivated grass field). Moreover, a case study has been analysed in Italy where metagenomic of soil micobiota was pictured in a production farm, in three plots differently managed in terms of fertilization, pesticide and tillage application: conventional, organic, no-tillage. Chapter I represents the general introduction of the thesis. Chapter II focuses on the practices of soil appropriation in the indigenous and urban Colombian contexts, both from biologically and socio-culturally point of view. The southern region of Colombian Amazon was taken into consideration, since this region constitutes an important model for the traditional utilization of natural resources and a fundamental basis for the definition of strategies for ecosystem management. In Chapter III the focus is on the mycological knowledge of Colombian soils based on data published in scientific research papers. Published data on diversity of native soil microfungi reported for the different natural regions of Colombia were analysed and compared. Some of the most relevant aspects of the country's mycological diversity are discussed and the most frequently registered species and genera, as well as the references for each of them, are presented. In Chapter IV the soil mycobiota in the Colombian High-Andean agro-environment is assessed through high-throughput sequencing technology. The chapter depicts the entire soil fungal community from qualitative and quantitative point of view in areas with different land use. The bootstrap-based clustering analysis highlighted that different land use strongly influences the soil mycobiota: the uncultivated and cultivated areas are characterized by abundant presence of some exclusive species. Differences in fungal species composition is consistent with the clustering analysis on higher taxonomic hierarchical level composition. Chapter V reports data collected in a case study planned in the Italian agro-environment context. The results showed that various agricultural management practices and seasonality influence the composition of the soil mycological community in agroecosystems, through a metagenomic picture. Metagenomic analyses show that the highest richness indices correspond to soils under organic production systems, while the non-tillage system showed the most divergent communities, with their own composition, prevalence and seasonal trends. Finally, the Chapter VI represents a sort of perspective for those areas subjected to conventional management and strongly polluted by pesticides that could be remediated and led towards a sustainable agriculture. The usefulness of soil fungi as key tools for the sustainable bioremediation of chemical pesticides in the soil is discussed as a strategy for the recovery of the quality of degraded agricultural soils. The results of this study provide insight into the complexity of micobiota of managed soils under different farming systems, with the ultimate goal of better understanding the multiple mechanisms governing soil quality and to develop an environmentally sound management that improves production, allowing the maintenance of ecosystem diversity and the wellness of human communities linked