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  1. Book ; Online: Tropical Forest Ecosystem Responses to Increasing Nutrient Availability

    Hertel, Dietrich / Baez, Selene / Homeier, Jurgen / Leuschner, Christoph

    2017  

    Abstract: Deforestation and land use change have led to a strong reduction of tropical forest cover during the last decades. Climate change will amplify the pressure to the remaining refuges in the next years. In addition, tropical regions are facing increasing ... ...

    Abstract Deforestation and land use change have led to a strong reduction of tropical forest cover during the last decades. Climate change will amplify the pressure to the remaining refuges in the next years. In addition, tropical regions are facing increasing atmospheric inputs of nutrients, which will have unknown consequences for the structure and functioning of these systems, no matter if they are within protected areas or not. Even remote areas are expected to receive rising amounts of nutrients. The effects of higher rates of atmospheric nutrient deposition on the biological diversity and ecosystem functioning of tropical ecosystems are poorly understood and our knowledge of nutrient fluxes and nutrient limitation in tropical forest ecosystems is still limited. Yet, it will be of paramount importance to know the effects of increased nutrient availability to conserve these ecosystems with their biological and functional diversity. During the last years, research efforts have more and more focused on the understanding of the role of nutrients in tropical ecosystems and several coordinated projects have been established that study the effects of experimental nutrient addition. This Research Topic combines results from experiments and from observational studies with the aim to review and conclude on our current knowledge on the role of additional nutrients in ecosystems
    Keywords Physical geography ; Science (General)
    Size 1 electronic resource (109 p.)
    Publisher Frontiers Media SA
    Document type Book ; Online
    Note English ; Open Access
    HBZ-ID HT020095931
    ISBN 9782889452279 ; 2889452271
    Database ZB MED Catalogue: Medicine, Health, Nutrition, Environment, Agriculture

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  2. Article ; Online: Changes in tree functional composition across topographic gradients and through time in a tropical montane forest.

    Báez, Selene / Fadrique, Belén / Feeley, Kenneth / Homeier, Jürgen

    PloS one

    2022  Volume 17, Issue 4, Page(s) e0263508

    Abstract: Understanding variation in tree functional traits along topographic gradients and through time provides insights into the processes that will shape community composition and determine ecosystem functioning. In montane environments, complex topography is ... ...

    Abstract Understanding variation in tree functional traits along topographic gradients and through time provides insights into the processes that will shape community composition and determine ecosystem functioning. In montane environments, complex topography is known to affect forest structure and composition, yet its role in determining trait composition, indices on community climatic tolerances, and responses to changing environmental conditions has not been fully explored. This study investigates how functional trait composition (characterized as community-weighted moments) and community climatic indices vary for the tree community as a whole and for its separate demographic components (i.e., dying, surviving, recruiting trees) over eight years in a topographically complex tropical Andean forest in southern Ecuador. We identified a strong influence of topography on functional composition and on species' climatic optima, such that communities at lower topographic positions were dominated by acquisitive species adapted to both warmer and wetter conditions compared to communities at upper topographic positions which were dominated by conservative cold adapted species, possibly due to differences in soil conditions and hydrology. Forest functional and climatic composition remained stable through time; and we found limited evidence for trait-based responses to environmental change among demographic groups. Our findings confirm that fine-scale environmental conditions are a critical factor structuring plant communities in tropical forests, and suggest that slow environmental warming and community-based processes may promote short-term community functional stability. This study highlights the need to explore how diverse aspects of community trait composition vary in tropical montane forests, and to further investigate thresholds of forest response to environmental change.
    MeSH term(s) Ecosystem ; Forests ; Plants ; Soil/chemistry ; Trees ; Tropical Climate
    Chemical Substances Soil
    Language English
    Publishing date 2022-04-20
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2267670-3
    ISSN 1932-6203 ; 1932-6203
    ISSN (online) 1932-6203
    ISSN 1932-6203
    DOI 10.1371/journal.pone.0263508
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article ; Online: Functional traits determine tree growth and ecosystem productivity of a tropical montane forest: Insights from a long-term nutrient manipulation experiment.

    Báez, Selene / Homeier, Jürgen

    Global change biology

    2017  Volume 24, Issue 1, Page(s) 399–409

    Abstract: Trait-response effects are critical to forecast community structure and biomass production in highly diverse tropical forests. Ecological theory and few observation studies indicate that trees with acquisitive functional traits would respond more ... ...

    Abstract Trait-response effects are critical to forecast community structure and biomass production in highly diverse tropical forests. Ecological theory and few observation studies indicate that trees with acquisitive functional traits would respond more strongly to higher resource availability than those with conservative traits. We assessed how long-term tree growth in experimental nutrient addition plots (N, P, and N + P) varied as a function of morphological traits, tree size, and species identity. We also evaluated how trait-based responses affected stand scale biomass production considering the community structure. We found that tree growth depended on interactions between functional traits and the type or combination of nutrients added. Common species with acquisitive functional traits responded more strongly to nutrient addition, mainly to N + P. Phosphorous enhanced the growth rates of species with acquisitive and conservative traits, had mostly positive effects on common species and neutral or negative effects in rare species. Moreover, trees receiving N + P grew faster irrespective of their initial size relative to trees in control or to trees in other treatment plots. Finally, species responses were highly idiosyncratic suggesting that community processes including competition and niche dimensionality may be altered under increased resource availability. We found no statistically significant effects of nutrient additions on aboveground biomass productivity because acquisitive species had a limited potential to increase their biomass, possibly due to their generally lower wood density. In contrast, P addition increased the growth rates of species characterized by more conservative resource strategies (with higher wood density) that were poorly represented in the plant community. We provide the first long-term experimental evidence that trait-based responses, community structure, and community processes modulate the effects of increased nutrient availability on biomass productivity in a tropical forest.
    MeSH term(s) Biomass ; Forests ; Nitrogen ; Phenotype ; Phosphorus ; Trees/growth & development ; Tropical Climate ; Wood
    Chemical Substances Phosphorus (27YLU75U4W) ; Nitrogen (N762921K75)
    Language English
    Publishing date 2017-10-11
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 1281439-8
    ISSN 1365-2486 ; 1354-1013
    ISSN (online) 1365-2486
    ISSN 1354-1013
    DOI 10.1111/gcb.13905
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article: Evaluating the Impacts of a Small-Grants Program on Sustainable Development and Biodiversity Conservation in Andean Forest Landscapes

    Báez, Selene / Mazzarino, Meagan / Peralvo, Manuel / Sears, Robin R

    Mountain research and development. 2020 Dec. 11, v. 40, no. 2

    2020  

    Abstract: International sustainable development and conservation agendas can help regional decision makers to frame their own agendas. Agendas can guide programs and initiatives that drive funding and capacity development for research, and the research, in turn, ... ...

    Abstract International sustainable development and conservation agendas can help regional decision makers to frame their own agendas. Agendas can guide programs and initiatives that drive funding and capacity development for research, and the research, in turn, provides knowledge, evidence, capacity building, and impetus for action. Deficits in research capacity, knowledge, and funding confound efforts on the impact pathway from agenda to outcome. Small-grants programs can play an important role in filling these gaps. In this paper, we evaluate a suite of impacts of a small-grants program linked to a regional research agenda for the Andean forest landscape. Using the concept of additionality, and analyzing the database of applications for the solicitation process and responses to a questionnaire by awardees, we evaluated the effects of the funding on research input, outputs and outcomes, and transformative application to sustainable development. We found that the solicitation process, which yielded 180 applications, fell short of its goal of attracting applicants well distributed among the Andean countries, applications from women, and applications for interdisciplinary transformative research projects. Nevertheless, the 15 projects that were funded did ultimately cross disciplinary lines, result in diverse outputs and outcomes, and help to advance work toward achieving sustainable development and biodiversity conservation in the Andean forest landscape. We recommend that small-grants programs that focus narrowly on a topic or region be supported and that they strive to elevate regional researchers and women in the community of practice.
    Keywords biodiversity conservation ; databases ; forests ; landscapes ; questionnaires ; research and development ; sustainable development ; Andes region
    Language English
    Dates of publication 2020-1211
    Size p. D1-D7.
    Publishing place International Mountain Society
    Document type Article
    Note NAL-AP-2-clean
    ZDB-ID 625728-8
    ISSN 0276-4741
    ISSN 0276-4741
    DOI 10.1659/MRD-JOURNAL-D-19-00066.1
    Database NAL-Catalogue (AGRICOLA)

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  5. Article: Lianas and trees exhibit divergent intrinsic water‐use efficiency along elevational gradients in South American and African tropical forests

    Mumbanza, Francis M. / Bauters, Marijn / Meunier, Félicien / Boeckx, Pascal / Cernusak, Lucas A. / De Deurwaerder, Hannes P. T. / Demol, Miro / Meeussen, Camille / Sercu, Bram / Verryckt, Lore T. / Pauwels, Jana / Cizungu, Landry N. / Báez, Selene / Lubini, Constantin A. / Verbeeck, Hans

    Global ecology and biogeography. 2021 Nov., v. 30, no. 11

    2021  

    Abstract: AIM: Elevational gradients provide excellent opportunities to explore long‐term morphological and physiological responses of plants to environmental change. We determined the difference in the elevational pattern of foliar carbon isotope composition (δ¹³ ... ...

    Abstract AIM: Elevational gradients provide excellent opportunities to explore long‐term morphological and physiological responses of plants to environmental change. We determined the difference in the elevational pattern of foliar carbon isotope composition (δ¹³C) between lianas and trees, and assessed whether this difference arises from changes in photosynthesis or stomatal conductance. We also explored the pattern of nutrient limitations with the elevation of these two growth forms. LOCATION: The study was conducted in two mountain forests situated in the Neotropics and Palaeotropics. TIME PERIOD: August–September 2015 and August–October 2016. MAJOR TAXA STUDIED: Lianas and trees. METHODS: We conducted inventories of lianas and trees using standardized techniques along elevational gradients in Ecuador and Rwanda. We determined the values of several foliar traits including δ¹³C and chemical traits in dominant liana and tree species. We set up Bayesian linear mixed‐effect models to quantify the effects of elevation and growth form on each of the foliar traits , and the difference of the effect of elevation between the two growth forms (lianas and trees). RESULTS: We found consistent growth form specific divergences in foliar δ¹³C and carbon to nitrogen ratio (C : N) responses to elevation. While we noted a meaningful increase in foliar δ¹³C and C : N with elevation for trees, lianas did not exhibit such a trend. Foliar δ¹³C and C : N remained relatively constant for lianas along the transects. MAIN CONCLUSIONS: Lianas operate at relatively constant intrinsic water‐ and nitrogen‐use efficiencies with elevation compared with trees. Altogether, the study suggests the existence of a functional divergence of water and nutrient use strategies between lianas and trees along tropical elevational transects.
    Keywords Bayesian theory ; Neotropics ; biogeography ; carbon ; carbon nitrogen ratio ; photosynthesis ; stomatal conductance ; trees ; water use efficiency ; Ecuador ; Rwanda
    Language English
    Dates of publication 2021-11
    Size p. 2259-2272.
    Publishing place John Wiley & Sons, Ltd
    Document type Article
    Note JOURNAL ARTICLE
    ZDB-ID 2021283-5
    ISSN 1466-8238 ; 1466-822X ; 0960-7447
    ISSN (online) 1466-8238
    ISSN 1466-822X ; 0960-7447
    DOI 10.1111/geb.13382
    Database NAL-Catalogue (AGRICOLA)

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  6. Article ; Online: Shrub invasion decreases diversity and alters community stability in northern Chihuahuan Desert plant communities.

    Báez, Selene / Collins, Scott L

    PloS one

    2008  Volume 3, Issue 6, Page(s) e2332

    Abstract: Background: Global climate change is rapidly altering species range distributions and interactions within communities. As ranges expand, invading species change interactions in communities which may reduce stability, a mechanism known to affect ... ...

    Abstract Background: Global climate change is rapidly altering species range distributions and interactions within communities. As ranges expand, invading species change interactions in communities which may reduce stability, a mechanism known to affect biodiversity. In aridland ecosystems worldwide, the range of native shrubs is expanding as they invade and replace native grassland vegetation with significant consequences for biodiversity and ecosystem functioning.
    Methodology: We used two long-term data sets to determine the effects of shrub encroachment by Larrea tridentata on subdominant community composition and stability in formerly native perennial grassland dominated by Bouteloua eriopoda in New Mexico, USA.
    Principal findings: Our results indicated that Larrea invasion decreased species richness during the last 100 years. We also found that over shorter temporal scales species-poor subdominant communities in areas invaded by Larrea were less stable (more variable in time) compared to species rich communities in grass-dominated vegetation. Compositional stability increased as cover of Bouteloua increased and decreased as cover of Larrea increased.
    Significance: Changes in community stability due to altered interspecific interactions may be one mechanism by which biodiversity declines in grasslands following shrub invasion. As global warming increases, shrub encroachment into native grasslands worldwide will continue to alter species interactions and community stability both of which may lead to a decline in biodiversity.
    MeSH term(s) Analysis of Variance ; Larrea/growth & development ; Larrea/physiology ; Linear Models ; Species Specificity
    Language English
    Publishing date 2008-06-04
    Publishing country United States
    Document type Journal Article ; Research Support, U.S. Gov't, Non-P.H.S.
    ISSN 1932-6203
    ISSN (online) 1932-6203
    DOI 10.1371/journal.pone.0002332
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  7. Article ; Online: Web-based environmental simulation: bridging the gap between scientific modeling and decision-making.

    Buytaert, Wouter / Baez, Selene / Bustamante, Macarena / Dewulf, Art

    Environmental science & technology

    2012  Volume 46, Issue 4, Page(s) 1971–1976

    Abstract: Data availability in environmental sciences is growing rapidly. Conventional monitoring systems are collecting data at increasing spatial and temporal resolutions; satellites provide a constant stream of global observations, and citizen scientist ... ...

    Abstract Data availability in environmental sciences is growing rapidly. Conventional monitoring systems are collecting data at increasing spatial and temporal resolutions; satellites provide a constant stream of global observations, and citizen scientist generate local data with electronic gadgets and cheap devices. There is a need to process this stream of heterogeneous data into useful information, both for science and for decision-making. Advances in networking and computer technologies increasingly enable accessing, combining, processing, and visualizing these data. This Feature reflects upon the role of environmental models in this process. We consider models as the primary tool for data processing, pattern identification, and scenario analysis. As such, they are an essential element of science-based decision-making. The new technologies analyzed here have the potential to turn the typical top-down flow of information from scientists to users into a much more direct, interactive approach. This may accelerate the dissemination of environmental information to a larger community of users. It may also facilitate harvesting feedback, and evaluating simulations and predictions from different perspectives. However, the evolution poses challenges, not only to model development but also to the communication of model results and their assumptions, shortcomings, and errors.
    MeSH term(s) Computer Simulation ; Decision Making ; Ecology ; Internet ; Models, Theoretical
    Language English
    Publishing date 2012-02-21
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ISSN 1520-5851
    ISSN (online) 1520-5851
    DOI 10.1021/es2031278
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  8. Article ; Online: Understanding climate change impacts on biome and plant distributions in the Andes: Challenges and opportunities

    Tovar, Carolina / Carril, Andrea F. / Gutiérrez, Alvaro G. / Ahrends, Antje / Fita, Lluis / Zaninelli, Pablo / Flombaum, Pedro / Abarzúa, Ana M. / Alarcón, Diego / Aschero, Valeria / Baéz, Selene / Barros, Agustina / Carilla, Julieta / Ferrero, M. Eugenia / Flantua, Suzette G. A. / Gonzáles, Paúl / Menéndez, Claudio G. / Pérez‐Escobar, Oscar A. / Pauchard, Aníbal /
    Ruscica, Romina C. / Särkinen, Tiina / Sörensson, Anna A. / Srur, Ana / Villalba, Ricardo / Hollingsworth, Peter M.

    Journal of biogeography. 2022 Aug., v. 49, no. 8 p.1420-1442

    2022  

    Abstract: AIM: Climate change is expected to impact mountain biodiversity by shifting species ranges and the biomes they shape. The extent and regional variation in these impacts are still poorly understood, particularly in the highly biodiverse Andes. Regional ... ...

    Abstract AIM: Climate change is expected to impact mountain biodiversity by shifting species ranges and the biomes they shape. The extent and regional variation in these impacts are still poorly understood, particularly in the highly biodiverse Andes. Regional syntheses of climate change impacts on vegetation are pivotal to identify and guide research priorities. Here we review current data, knowledge and uncertainties in past, present and future climate change impacts on vegetation in the Andes. Location: Andes. Taxon: Plants. METHODS: We (i) conducted a literature review on Andean vegetation responses to past and contemporary climatic change, (ii) analysed future climate projections for different elevations and slope orientations at 19 Andean locations using an ensemble of model outputs from the Coupled Model Intercomparison Project 5, and (iii) calculated changes in the suitable climate envelope area of Andean biomes and compared these results to studies that used species distribution models. RESULTS: Future climatic changes (2040–2070) are projected to be stronger at high‐elevation areas in the tropical Andes (up to 4°C under RCP 8.5), while in the temperate Andes temperature increases are projected to be up to 2°C. Under this worst‐case scenario, temperate deciduous forests and the grasslands/steppes from the Central and Southern Andes are predicted to show the greatest losses of suitable climatic space (30% and 17%–23%, respectively). The high vulnerability of these biomes contrasts with the low attention from researchers modelling Andean species distributions. Critical knowledge gaps include a lack of an Andean wide plant checklist, insufficient density of weather stations at high‐elevation areas, a lack of high‐resolution climatologies that accommodates the Andes' complex topography and climatic processes, insufficient data to model demographic and ecological processes, and low use of palaeo data for distribution modelling. MAIN CONCLUSIONS: Climate change is likely to profoundly affect the extent and composition of Andean biomes. Temperate Andean biomes in particular are susceptible to substantial area contractions. There are, however, considerable challenges and uncertainties in modelling species and biome responses and a pressing need for a region‐wide approach to address knowledge gaps and improve understanding and monitoring of climate change impacts in these globally important biomes.
    Keywords biodiversity ; biogeography ; climate ; climate change ; ecosystems ; geographical distribution ; models ; temperature ; weather ; Andes region
    Language English
    Dates of publication 2022-08
    Size p. 1420-1442.
    Publishing place John Wiley & Sons, Ltd
    Document type Article ; Online
    Note REVIEW
    ZDB-ID 188963-1
    ISSN 0305-0270
    ISSN 0305-0270
    DOI 10.1111/jbi.14389
    Database NAL-Catalogue (AGRICOLA)

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  9. Article ; Online: (with research data) Ant Mutualism Increases Long-Term Growth and Survival of a Common Amazonian Tree.

    Báez, Selene / Donoso, David A / Queenborough, Simon A / Jaramillo, Liliana / Valencia, Renato / Dangles, Olivier

    The American naturalist

    2016  Volume 188, Issue 5, Page(s) 567–575

    Abstract: How ecological context shapes mutualistic relationships remains poorly understood. We combined long-term tree census data with ant censuses in a permanent 25-ha Amazonian forest dynamics plot to evaluate the effect of the mutualistic ant Myrmelachista ... ...

    Abstract How ecological context shapes mutualistic relationships remains poorly understood. We combined long-term tree census data with ant censuses in a permanent 25-ha Amazonian forest dynamics plot to evaluate the effect of the mutualistic ant Myrmelachista schumanni (Formicinae) on the growth and survival of the common Amazonian tree Duroia hirsuta (Rubiaceae), considering its interactions with tree growth, population structure, and habitat. We found that the mutualist ant more than doubled tree relative growth rates and increased odds of survival. However, host tree size and density of conspecific neighbors modified the effect of the ant. Smaller trees hosting the mutualist ant consistently grew faster when surrounded by higher densities of conspecifics, suggesting that the benefit to the tree outweighs any negative effects of high conspecific densities. Moreover, our findings suggest that the benefit afforded by the ant diminishes with plant age and also depends on the density of conspecific neighbors. We provide the first long-term large-scale evidence of how mutualism affects the population biology of an Amazonian tree species.
    MeSH term(s) Animals ; Ants ; Ecosystem ; Rubiaceae ; Symbiosis ; Trees
    Language English
    Publishing date 2016-11
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 207092-3
    ISSN 1537-5323 ; 0003-0147
    ISSN (online) 1537-5323
    ISSN 0003-0147
    DOI 10.1086/688401
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  10. Article: Edge effects on palm diversity in rain forest fragments in western Ecuador

    Baez, Selene / Balslev, Henrik

    Biodiversity and conservation. 2007 June, v. 16, no. 7

    2007  

    Abstract: At the edges of tropical rain forest fragments, altered abiotic and biotic conditions influence the structure and dynamics of plant communities. In Neotropical rain forests, palms (Arecaceae) are important floristic and ecological elements. Palms' ... ...

    Abstract At the edges of tropical rain forest fragments, altered abiotic and biotic conditions influence the structure and dynamics of plant communities. In Neotropical rain forests, palms (Arecaceae) are important floristic and ecological elements. Palms' responses to edge effects appear to be idiosyncratic and to depend on the level of disturbance at edges. This paper explores how variation in forest structure at the edges of two old-growth forest fragments in a tropical rain forest in western Ecuador affects palms of different species, life-forms, and size classes. We investigate (1) how edge effects influence the relative proportion of palm adults and juveniles, (2) how distance from the forest edge affects palm density and species richness, (3) how altered forest structure along edges affects palm density. We found that at edges (1) palm communities had a lower proportion of adults relative to juvenile individuals compared to continuous forests, (2) the density of two species of palms and the overall species richness of the palm community tended to decrease toward the edges within forest fragments, and, (3) altered forest structure decreased the density of adult palms. Hence, edge effects on palms were controlled by the degree of modification of the forest structure, and by species responses to edge-related disturbance.
    Keywords density
    Language English
    Dates of publication 2007-06
    Size p. 2201-2211.
    Publisher Kluwer Academic Publishers
    Publishing place Dordrecht
    Document type Article
    ZDB-ID 2000787-5
    ISSN 1572-9710 ; 0960-3115
    ISSN (online) 1572-9710
    ISSN 0960-3115
    DOI 10.1007/s10531-007-9159-5
    Database NAL-Catalogue (AGRICOLA)

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