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The composition of plant functional traits varies in response to environmental conditions due to processes of community assembly and species sorting. However, there is a lack of understanding of how plant trait composition responds to environmental conditions at different spatial scales and across the plant life cycle. We investigated the trait composition of leaves (specific leaf area), seeds (seed mass) and seedlings (initial seedling height) across elevations and within elevations in relation to soil and light conditions in a tropical montane forest in southern Ecuador. We surveyed traits and communities of adult trees, seeds and seedlings on nine plots at three elevations (1000–3000 m a.s.l.) and calculated community‐weighted mean trait values to analyse trait variation across and within elevations. In addition, we measured two environmental factors (soil C/N ratio and canopy openness) to quantify local‐scale variation in environmental conditions within elevations. We found that community‐weighted means of specific leaf area, seed mass and initial seedling height decreased consistently with increasing elevation. Within elevations, mean trait values of trees, seeds and seedlings responded differently to local‐scale environmental conditions. Specific leaf area decreased with increasing soil C/N ratio, and initial seedling height decreased with increasing canopy openness. Seed mass was associated neither with soil nor with light conditions. Our findings show that broad‐scale and local‐scale processes differently shape the composition of leaf, seed and seedling traits in tropical forests, indicating a scale‐dependence in trait–environment associations. Furthermore, plant traits corresponding to different life stages were related differently to environmental conditions within elevations. Community assembly processes may therefore lead to differences in species sorting at early and late plant life stages. [ABSTRACT FROM AUTHOR]

The co‐evolutionary arms race between herbivores and plants forces plants to evolve protection strategies that reduce the palatability of the plant modules attacked by the herbivores. These characteristics of traits have consequences for both the survival of plant individuals and the composition of plant communities. Thus, correlating traits of for instance leaves with herbivory is an important step toward understanding the dynamics of plant populations and communities. Traits can either be measured using conventional lab methods or recently developed spectral sensing techniques. We examined whether leaf traits of trees are related to herbivory in a multispecies approach. Furthermore, we explored whether leaf traits characterized by spectral sensing provide similar relations to herbivory as lab‐based leaf traits. We established nine 1‐ha square plots evenly distributed over three different forest types in Ecuadorian tropical montane rainforests where we estimated herbivory as the leaf area loss (in square centimeters) of 20 (±5) leaves sampled from the canopies of 380 tree individuals belonging to 51 tree species (7 ± 1 individuals/species) using lab‐ and spectral‐sensing‐based methods. For each methodological approach, we ran 100 linear mixed‐effects models with all respective leaf traits as predictor and herbivory as response variables for data subsets containing one randomly selected tree individual of each species to estimate the range of the regression coefficients for each trait. Automated stepwise backward selections determined the frequency of each trait having an important influence on herbivory. We found no clear relations between leaf traits and herbivory for neither lab‐ nor spectral‐sensing‐based traits. A nested variance component analysis demonstrated that the observed variability was mainly due to the variation in trait concentrations between tree individuals of a species. Our results suggest that snapshot data lead to a mismatch between herbivory and the concentrations of traits during the peak of herbivory. Another explanation could be that environmental conditions or processes along the food web are more important in structuring herbivory than leaf traits. [ABSTRACT FROM AUTHOR]

The globally increasing reactive N richness affects even remote ecosystems such as the tropical montane forests in Ecuador. We tested whether the δ15N values of total dissolved N (TDN), measured directly in solution with a TOC‐IRMS, can be used to help elucidate N sources and sinks along the water path and thus might be suitable for ecosystem monitoring. From 2013 to 2016, the δ15N values of TDN in bulk deposition showed the most pronounced temporal variation of all ecosystem solutions (δ15N values: 1.9–5.9‰). In throughfall (TF), TDN was on average 15N‐depleted (−1.8 ± s.d. 0.4‰) relative to rainfall (3.4 ± 0.9‰), resulting from net retention of isotopically heavy N, mainly as NH4+. Simultaneously, N‐isotopically light NO3−‐N and dissolved organic nitrogen (DON) with a δ15N value between NO3−‐N and NH4+‐N were leached from the canopy (leaves: −3.5 ± 0.5‰). The increasing δ15N values in the order, TF < stemflow (SF, 0.1 ± 0.6‰)< litter leachate (LL, 1.3 ± 0.7‰) concurred with an increasing DON contribution to TDN reflecting the δ15N value of the organic layer (1.9 ± 0.9‰). The lower δ15N value of the mineral soil solution at the 0.15 m soil depth (SS15, −1.5 ± 0.3‰) than in LL can be explained by the retention of DON and NH4+ and the addition of NO3− from mineralization and nitrification. The increasing δ15N values in the order, SS15 < SS30 (−0.6 ± 0.2‰) < streamflow (ST, 0.5 ± 0.6‰) suggested gaseous N losses because of increasing denitrification. There was no seasonality of the δ15N values. Our results demonstrate that the δ15N values of TDN in ecosystem solutions help identify N sources and sinks in forest ecosystems. Plain Language Summary: Many ecosystems experience increasing nitrogen availability because of nitrogen deposition from the atmosphere caused by human activities. The deposited nitrogen can produce a growth boost or be leached into groundwater and surface water. The stable isotope ratios of nitrogen (δ15N values) provide a tool to investigate into the consequences of increasing nitrogen availability. Here, we applied a new direct measurement method of δ15N values in total dissolved nitrogen of ecosystem solutions to follow sources and sinks of nitrogen in a tropical montane rain forest in Ecuador. We found that the isotopically heavy nitrogen input via rainfall is enriched by isotopically lighter nitrogen from plants and nitrogen turnover during the water passage through the canopy. Once, the solutions reach the mineral soil, dissolved organic nitrogen, which is comparatively rich in the heavy nitrogen isotope, is retained rendering the remaining nitrogen isotopically lighter. This process is reversed deeper in the soil by conversion of the nitrate to nitrogen gasses, which are depleted in the heavy nitrogen isotope and leave the ecosystem to the atmosphere. The direct measurement of δ15N values provides a tool to monitor the changing nitrogen cycle in ecosystems. Key Points: Increasing δ15N values in total dissolved nitrogen from throughfall to litter leachate correlated with an increasing organic contributionThe retention of N‐isotopically heavy dissolved organic nitrogen in the mineral topsoil decreased the δ15N values in mineral soil solutionsIncreasing δ15N values from the topsoil solution via the subsoil to the streamflow suggested gaseous N losses because of denitrification [ABSTRACT FROM AUTHOR]

The question whether the strategies of above‐ and belowground plant organs are coordinated as predicted by the plant economics spectrum theory is still under debate. We aim to determine the leading dimensions of tree trait variation for above‐ and belowground functional traits, and test whether they represent spectra of adaptation along a soil fertility gradient in tropical Andean forests.We measured leaf, stem and fine root functional traits, and individual‐level soil nutrient availability for 433 trees from 52 species at three elevations between 1000 and 3000 m a.s.l.We found close coordination between above– and belowground functional traits related to the trade‐off between resource acquisition and conservation, whereas root diameter and specific root length formed an independent axis of covarying traits. The position of a tree species along the acquisition–conservation axis of the trait space was closely associated with local soil nitrogen, but not phosphorus, availability.Our results imply that above‐ and belowground plant functional traits determine at which edaphic microhabitats coexisting tree species can grow, which is potentially crucial for understanding community assembly in species‐rich tropical montane forests. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

Ferns are known to have a lower incidence of mycorrhization than angiosperms. It has been suggested that this results from carbon being more limiting to fern growth than nutrient availability, but this assertion has not been tested yet. In the present study, we took advantage of a fertilization experiment with nitrogen and phosphorus on cloud forest plots of the Ecuadorean Andes for 15 years. A previous analysis revealed changes in the abundances of fern species in the fertilized plots compared to the control plots and hypothesized that this might be related to the responses of the mycorrhizal relationships to nutrient availability. We revisited the plots to assess the root‐associated fungal communities of two epiphytic and two terrestrial fern species that showed shifts in abundance. We sampled and analyzed the roots of 125 individuals following a metabarcoding approach. We recovered 1382 fungal ASVs, with a dominance of members of Tremellales (Basidiomycota) and Heliotales (Ascomycota). The fungal diversity was highly partitioned with little overlap between individuals. We found marked differences between terrestrial and epiphytic species, with the latter fundamentally missing arbuscular mycorrhizal fungi (AMF). We found no effect of fertilization on the diversity or relative abundance of the fungal assemblages. Still, we observed a direct impact of phosphorus fertilization on its concentration in the fern leaves. We conclude that fern–fungi relationships in the study site are not restricted by nutrient availability and suggest the existence of little specificity on the fungal partners relative to the host fern species. [ABSTRACT FROM AUTHOR]

With increasing elevation, trees in tropical montane forests have to invest larger fractions of their resources into their fine roots in order to compensate for increasingly unfavorable soil conditions. It is unclear how elevation and related edaphic changes influence the variability in tree fine root traits and belowground functional diversity. We measured six fine root traits related to resource acquisition on absorptive fine roots of 288 trees from 145 species along an elevational gradient from 1000 m to 3000 m a.s.l. in tropical montane forests of the Ecuadorian Andes. We analyzed trait relationships with elevation and soil nutrient availability, and tested whether root functional diversity varied along these gradients. Fine roots at higher elevations and at more nutrient‐poor sites were thicker, had higher tissue densities, and lower specific root length and nutrient concentrations than at lower elevations. These trends were diluted by the coexistence of tree species with a broad range of different root traits within communities particularly towards lower elevations, where root functional diversity was significantly higher. We conclude that nutrient limitation and potentially further adverse conditions at higher elevations are strong environmental filters that lead to trait convergence towards a conservative resource use strategy, whereas different trait syndromes are equally successful at lower elevations. [ABSTRACT FROM AUTHOR]

Root associated fungal (RAF) communities can exert strong effects on plant communities and are potentially sensitive to shifts in soil fertility. As increased atmospheric nitrogen (N) and phosphorus (P) deposition can alter the nutrient balance in natural ecosystems, we assessed the response of RAF communities to a fertilization experiment deployed on a highly diverse Andean forest. The stand level fine root fraction was sampled after 7 years of systematic N and P additions and RAF communities were characterized by a deep sequencing approach. We expected that fertilization will enhance competition of fungal taxa for limiting nutrients, thus eliciting diversity reductions and alterations in the structure of RAF communities. Fertilization treatments did not reduce RAF richness but affected community composition. At the phylum level fertilization reduced richness exclusively among Glomeromycota. In contrast, N and P additions (alone or in combination) altered the composition of several fungal phyla. The lack of a generalized response to long‐term fertilization among RAF lineages suggests that most of these lineages will not be directly and immediately affected by the increasing rates of atmospheric N and P deposition expected for this region by 2050. [ABSTRACT FROM AUTHOR]

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Summary: Community trait assembly in highly diverse tropical rainforests is still poorly understood. Based on more than a decade of field measurements in a biodiversity hotspot of southern Ecuador, we implemented plant trait variation and improved soil organic matter dynamics in a widely used dynamic vegetation model (the Lund‐Potsdam‐Jena General Ecosystem Simulator, LPJ‐GUESS) to explore the main drivers of community assembly along an elevational gradient.In the model used here (LPJ‐GUESS‐NTD, where NTD stands for nutrient‐trait dynamics), each plant individual can possess different trait combinations, and the community trait composition emerges via ecological sorting. Further model developments include plant growth limitation by phosphorous (P) and mycorrhizal nutrient uptake.The new model version reproduced the main observed community trait shift and related vegetation processes along the elevational gradient, but only if nutrient limitations to plant growth were activated. In turn, when traits were fixed, low productivity communities emerged due to reduced nutrient‐use efficiency. Mycorrhizal nutrient uptake, when deactivated, reduced net primary production (NPP) by 61–72% along the gradient.Our results strongly suggest that the elevational temperature gradient drives community assembly and ecosystem functioning indirectly through its effect on soil nutrient dynamics and vegetation traits. This illustrates the importance of considering these processes to yield realistic model predictions. [ABSTRACT FROM AUTHOR]

Background: Physical elder abuse affects a substantial number of older adults, leaving victims at increased risk for negative health outcomes. Improved detection of abuse‐related injuries may increase victim access to professional support, but providers report difficulties distinguishing between accidental and abuse‐related injuries, due in part to victims' pre‐existing health conditions and medication use. Objectives: To describe the spectrum and characteristics of injuries among physically abused older adults and identify injury characteristics associated with abuse. Design: Case–control study. Setting: Physically abused adult protective services clients were interviewed in their home; non‐abused comparison group participants were interviewed in an outpatient geriatrics clinic. Participants: Sample included 156 community‐dwelling adults aged 65 and older, including 57 physically abused and 99 non‐abused individuals. Self‐reported abuse history was confirmed through independent case assessment by a LEAD (Longitudinal, Expert All‐Data) panel of clinicians with family violence expertise. Measurements: Full‐body assessments were conducted, documenting injury incidence, diagnosis, and location. We also collected sociodemographic characteristics, level of social support, functional ability, medical history, and medication use. Results: Physically abused older adults were more likely to be injured upon assessment (79.0% vs 63.6%; p < 0.05) and have a greater number of injuries (x¯=2.9 vs x¯=2.0, p < 0.05). Injuries seen more often among abused individuals included: upper extremity ecchymoses (42.1% vs 26.3%; p < 0.05), abrasions (31.6% vs 11.1%; p < 0.01), and areas of tenderness (8.8% vs 0.0%; p < 0.01); and head/neck/maxillofacial ecchymoses (15.8% vs 2.0%; p < 0.01) and tenderness (15.8% vs 0.0%; p < 0.001). Lower extremity abrasions (12.3%) were common but unrelated to abuse status. Conclusion: While physical abuse does not always result in physical injury, victims more commonly display head/neck/maxillofacial ecchymoses or tenderness and upper extremity abrasions, ecchymoses, or tenderness. Detection of these injuries among older adults warrants further interview and examination. [ABSTRACT FROM AUTHOR]

We investigated the variation in tree fine root traits and their functional diversity along a local topographic gradient in a Neotropical montane forest to test if fine root trait variation along the gradient is consistent with the predictions of the root economics spectrum on a shift from acquisitive to conservative traits with decreasing resource supply.We measured five fine root functional traits in 179 randomly selected tree individuals of 100 species and analysed the variation of single traits (using Bayesian phylogenetic multilevel models) and of functional trait diversity with small‐scale topography.Fine roots exhibited more conservative traits (thicker diameters, lower specific root length and nitrogen concentration) at upper slope compared with lower slope positions, but the largest proportion of variation (40–80%) was explained by species identity and phylogeny. Fine root functional diversity decreased towards the upper slopes.Our results suggest that local topography and the related soil fertility and moisture gradients cause considerable small‐scale variation in fine root traits and functional diversity along tropical mountain slopes, with conservative root traits and greater trait convergence being associated with less favourable soil conditions due to environmental filtering. We provide evidence of a high degree of phylogenetic conservation in fine root traits. [ABSTRACT FROM AUTHOR]

In this paper, a class of weighted quadrature methods is introduced for smooth functions based upon the use of the mean value theorems. These new quadrature rules are also treated in a systematic approach involving formal series expansion. The convergence analysis of the proposed method is studied here for both the non‐weighted and the weighted cases. Some potential areas and directions for extensions and applications of the results, which are presented in this paper, are also indicated. [ABSTRACT FROM AUTHOR]

The newly described zoonotic variegated squirrel bornavirus 1 (VSBV‐1) in German squirrel holdings has been associated with the death of three private owners and one zoo animal caretaker (confirmed cases). Epidemiological investigations were severely impeded by the general lack of data on holdings of the putative reservoir hosts, the family Sciuridae. To fill this lack of data for detailed epidemiological investigations of the captive squirrel population, a register of private and zoological squirrel holdings was established. The findings show a broad variety of kept species and their frequency distribution. By contacting the different stakeholders via Web‐based social groups and societies, information passed in both directions so that disease awareness could be raised and participants could be recruited for further studies. Cross‐sectional studies revealed a prevalence of VSBV‐1‐positive subpopulations of 0% (95% CI 0%–6.2%) among private squirrel collections and 1.9% (95% CI: 0%–9.9%) among zoos in Germany. The approach presented here can be transferred to other populations of non‐traditional pets, which may be equally difficult to monitor, in the case of an emerging zoonotic infectious disease. [ABSTRACT FROM AUTHOR]

Objective: Treatment delays for refractory convulsive status epilepticus (RCSE) are associated with worse outcomes. In the United States, treatment for pediatric RCSE is slower than guidelines recommend. To address this gap, the American Academy of Neurology and Child Neurology Society (AAN/CNS) developed a quality measure: the percentage of RCSE patients that receive third‐line treatment within 60 minutes. We aimed to develop computable phenotypes for convulsive status epilepticus (CSE) and RCSE to automate calculation of the quality measure. Methods: From an observational cohort of children presenting to the emergency department for seizures or epilepsy, we identified presentations of RCSE and its precursors: CSE and benzodiazepine‐resistant status epilepticus (BRSE). These served as a gold standard for computable phenotype development. Using multivariate analyses, we constructed and evaluated statistical models for case identification. We then evaluated adherence to the AAN/CNS RCSE quality measure. Results: From 664 charts, we identified 56 patients with CSE, 36 with BRSE, and 18 with RCSE. Four predictors were used: International Classification of Diseases (ICD) codes, and receiving first‐, second‐, or third‐line agents shortly after presentation to the emergency department (ED). Combinations of these predictors identified CSE with 84% sensitivity and 81% positive predictive value (PPV), BRSE with 67% sensitivity and 89% PPV, and RCSE with 94% sensitivity and 85% PPV. Median (interquartile range [IQR]) time to treatment for first‐line agent was 13 (5‐27) minutes for CSE, second‐line for BRSE was 24 (9.5‐43.5) minutes, and third‐line for RCSE was 52 (27‐87) minutes. Sixty percent of RCSE patients received a third‐line agent within 60 minutes of ED arrival. Significance: RCSE and its precursors can be identified automatically with high fidelity allowing automated calculation of time to treatment and the RCSE quality measure. This has the potential to facilitate quality improvement work and improve care for RCSE. [ABSTRACT FROM AUTHOR]

Summary: Anthropogenic atmospheric deposition can increase nutrient supply in the most remote ecosystems, potentially affecting soil biodiversity. Arbuscular mycorrhizal fungal (AMF) communities rapidly respond to simulated soil eutrophication in tropical forests. Yet the limited spatio‐temporal extent of such manipulations, together with the often unrealistically high fertilization rates employed, impedes generalization of such responses.We sequenced mixed root AMF communities within a seven year‐long fully factorial nitrogen (N) and phosphorus (P) addition experiment, replicated at three tropical montane forests in southern Ecuador with differing environmental characteristics. We hypothesized: strong shifts in community composition and species richness after long‐term fertilization, site‐ and clade‐specific responses to N vs P additions depending on local soil fertility and clade life history traits respectively.Fertilization consistently shifted AMF community composition across sites, but only reduced richness of Glomeraceae. Compositional changes were mainly driven by increases in P supply while richness reductions were observed only after combined N and P additions.We conclude that moderate increases of N and P exert a mild but consistent effect on tropical AMF communities. To predict the consequences of these shifts, current results need to be supplemented with experiments that characterize local species‐specific AMF functionality. [ABSTRACT FROM AUTHOR]

Conversion of tropical forests is among the primary causes of global environmental change. The loss of their important environmental services has prompted calls to integrate ecosystem services (ES) in addition to socio‐economic objectives in decision‐making. To test the effect of accounting for both ES and socio‐economic objectives in land‐use decisions, we develop a new dynamic approach to model deforestation scenarios for tropical mountain forests. We integrate multi‐objective optimization of land allocation with an innovative approach to consider uncertainty spaces for each objective. These uncertainty spaces account for potential variability among decision‐makers, who may have different expectations about the future. When optimizing only socio‐economic objectives, the model continues the past trend in deforestation (1975–2015) in the projected land‐use allocation (2015–2070). Based on indicators for biomass production, carbon storage, climate and water regulation, and soil quality, we show that considering multiple ES in addition to the socio‐economic objectives has heterogeneous effects on land‐use allocation. It saves some natural forest if the natural forest share is below 38%, and can stop deforestation once the natural forest share drops below 10%. For landscapes with high shares of forest (38%–80% in our study), accounting for multiple ES under high uncertainty of their indicators may, however, accelerate deforestation. For such multifunctional landscapes, two main effects prevail: (a) accelerated expansion of diversified non‐natural areas to elevate the levels of the indicators and (b) increased landscape diversification to maintain multiple ES, reducing the proportion of natural forest. Only when accounting for vascular plant species richness as an explicit objective in the optimization, deforestation was consistently reduced. Aiming for multifunctional landscapes may therefore conflict with the aim of reducing deforestation, which we can quantify here for the first time. Our findings are relevant for identifying types of landscapes where this conflict may arise and to better align respective policies. [ABSTRACT FROM AUTHOR]

Partner choice in species interaction networks, that is, between frugivorous birds and fruiting plants, is largely determined by matching of functional traits. However, the composition of functional traits in plant communities changes along land‐use gradients. Understanding how flexible consumers react to changes in the trait composition of resources is crucial to project consequences for ecosystem functions, such as seed dispersal.We investigated the ability of birds to consume fruits with different sets of traits in natural and fragmented tropical montane forests across an elevational gradient. We developed a novel, trait‐based approach to quantify the functional shifts of consumers between resources with different functional traits. We expected the degree of functional shifts to be associated with bird traits related to food choice, such as bill width and degree of frugivory, as well as foraging behaviour, such as wing shape and foraging stratum.We sampled the plant–frugivore networks at three elevations and two habitat types (natural and fragmented forest) and measured the functional traits for each plant and bird species. We calculated the trait space of the plant community at each elevation and projected the interacting birds into it. Finally, we calculated the functional shift, which is the trait‐based distance between the preferred fruit resources in the two habitat types for each bird species.We found differences in the functional trait space of the fruiting plant community between natural and fragmented forests across all elevations. Birds' observed functional shifts between habitat types at each elevation were generally larger than the shifts expected by null models. Wing shape was the most important trait related to the functional shifts across the elevational gradient, whereas bill width, degree of frugivory, foraging stratum and phylogeny were not important.We conclude that birds with pointed wings respond flexibly to changes in the trait composition of fruit resources, probably due to the high mobility of these species. Our results emphasize that linking species interaction networks and functional trait analyses yield new insights into how consumer species respond to changes in biotic factors and can improve projections of how human impacts modify trophic interactions and associated ecosystem functions. A plain language summary is available for this article. Plain Language Summary [ABSTRACT FROM AUTHOR]

Tropical forests harbor diverse ecological communities of plants and animals that are organized in complex interaction networks. The diversity and structure of plant–animal interaction networks may change along elevational gradients and in response to human‐induced habitat fragmentation. While previous studies have analyzed the effects of elevation and forest fragmentation on species interaction networks in isolation, to our knowledge no study has investigated whether the effects of forest fragmentation on species interactions may differ along elevational gradients. In this study, we analyzed main and interaction effects of elevation and forest fragmentation on plant–frugivore interaction networks at plant and bird species level. Over a period spanning two years, we recorded plant–frugivore interactions at three elevations (1000, 2000 and 3000 m a.s.l.) and in two habitat types (continuous and fragmented forest) in tropical montane forests in southern Ecuador. We found a consistent effect of elevation on the structure of plant–frugivore networks. We observed a decrease in the number of effective bird partners of plants and, thus, a decline in the redundancy of bird species with increasing elevation. Furthermore, bird specialization on specific plant partners increased towards high elevations. Fragmentation had a relatively weak effect on the interaction networks for both plant and bird species, but resulted in a significant increase in bird specialization in fragmented forests at high elevations. Our results indicate that forest fragmentation may have stronger effects on plant–frugivore interaction networks at high compared to low elevations because bird species richness declined more steeply towards high elevations than plant species richness. We conclude that conservation efforts should prioritize the maintenance of consumer diversity, for instance by maintaining stretches of continuous forest. This applies in particular to species‐poor communities, such as those at high elevations, as the ecological processes in these communities seem most sensitive towards forest fragmentation. [ABSTRACT FROM AUTHOR]

Global changes in nutrient deposition rates are likely to have profound effects on plant communities, particularly in the nutrient-limited systems of the tropics. We studied the effects of increased nutrient availability on the seedlings of six tree species in montane forests of southern Ecuador in situ. After five years of continued N, P, or N+P addition, naturally grown seedlings of each of the two most common species at each elevation (1000, 2000, and 3000 m asl) were harvested for analyses of leaf morphology, nutrient content, herbivory, and tissue biomass allocation. Most species showed increased foliar N and P concentrations after addition of each respective element. Leaf tissue N:P ratios of >20 in the control plants of all species suggest that P is more growth-limiting in these forests than N. Leaf morphological responses to nutrient addition were species and nutrient specific, with some species (Hedyosmum purparescens, Graffenrieda emarginata) exhibiting increased specific leaf area (SLA), and others (Graffenrieda harlingii) increased leaf area ratios (LAR). Pouteria torta (1000 m) had lower SLA and LAR after P addition. Increased herbivory was only evident in G. emarginata (after N and N+P addition). Only the species from 3000 m asl modified biomass allocation after nutrient addition. In general, N and N+P addition more strongly affected the species studied at the upper elevations, whereas P addition had a similar range of effects on the species at all elevations. We conclude that the responses of the studied tropical montane forest tree seedlings to chronic N and P addition are highly species-specific and that successful adaptation to increased nutrient availability will depend on species-specific morphological and physiological plasticity. [ABSTRACT FROM AUTHOR]

Summary: Several thousands of tank bromeliads per hectare of neotropical forest create a unique wetland ecosystem that emits substantial amounts of CH4. Tank bromeliads growing in the forest canopy (functional type‐II tank bromeliads) were found to emit more CH4 than tank bromeliads growing on the forest floor (functional type‐I tank bromeliads) but the reasons for this difference and the underlying microbial CH4‐cycling processes have not been studied. Therefore, we characterized archaeal communities in bromeliad tanks of the two different functional types in a neotropical montane forest of southern Ecuador using terminal‐restriction fragment length polymorphism (T‐RFLP) and performed tank‐slurry incubations to measure CH4 production potential, stable carbon isotope fractionation and pathway of CH4 formation. The archaeal community composition was dominated by methanogens and differed between bromeliad functional types. Hydrogenotrophic Methanomicrobiales were the dominant methanogens and hydrogenotrophic methanogenesis was the dominant methanogenic pathway among all bromeliads. The relative abundance of aceticlastic Methanosaetaceae and the relative contribution of aceticlastic methanogenesis increased in type‐I tank bromeliads probably due to more oxic conditions in type‐I than in type‐II bromeliads leading to the previously observed lower in situ CH4 emissions from type‐I tank bromeliads but to higher CH4 production potentials in type‐I tank bromeliad slurries. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

This study presents a case study of large wood transport on the great Slave River in northern Canada with the objective to better understand the processes of and variability in pulsed wood fluxes from large forested catchments. We use a varied approach, integrating field characterization of wood, historical anecdotes, repeat aerial imagery of stored wood, and time-lapse imagery of moving wood, for a robust analysis and synthesis of processes behind pulsed wood flux, from yearly uncongested export to rare congested wood floods. Repeat monitoring of known sites of temporary storage with new or historic imagery proved to be a very useful tool for constraining wood flux histories. Pulsed wood export on the Slave River is not an artifact of episodic recruitment from major up-basin disturbances, but rather reflects decadal- to half-century-scale discharge patterns that redistribute wood recruited from channel migration and bank slumping. We suggest that the multiyear flow history is of paramount importance for estimating wood flux magnitude, followed in declining importance by the yearly sequence of peaks and the magnitude and characteristics of the rising limb of individual floods. [ABSTRACT FROM AUTHOR]

Questions How does the structure of liana communities (diameter, density and biomass) in tropical montane forests vary along elevation and topographic gradients? How do patterns of tree infestation vary with elevation? Is tree diameter growth reduced by lianas in tropical montane forest? Location Tropical Andean forests (1000-3000 m a.s.l.) in the San Francisco Reserve and in the Podocarpus National Park, southern Ecuador. Methods All lianas ( DBH ≥ 1 cm) were censused in 54 permanent plots (20 × 20 m) equally distributed between three study sites (1000, 2000 and 3000 m a.s.l.) and three topographic positions (lower, mid and upper slope) per site (six replicate plots at each site by position combination). The DBH and number of lianas hosted was recorded for all trees ( DBH ≥ 10 cm). Liana biomass was estimated using allometric equations. ANOVAs were used to test for effects of elevation and slope positions on liana parameters and proportion of trees infested. The relationships between liana biomass and tree parameters and environmental parameters were analysed with partial least squares regression. We used the available literature data to perform a regression analysis of liana biomass in response to elevation in humid tropical old-growth forests between sea level and 3000 m a.s.l. Results Liana diameter, density and biomass all decrease with elevation. The decreasing liana biomass agrees with results from previous studies of liana biomass in other humid tropical forests, indicating a decrease of 0.18 Mg·ha−1 liana biomass per 100 m of elevation gain. Topographic variation leads to thinner but more abundant stems upslope; there was no effect of topographic position on liana biomass. Liana biomass and liana infestation are both positively correlated with host tree DBH at every elevation. Tree diameter growth is reduced by liana infestation; the proportion of infested trees is lower in Andean montane forests than in tropical lowland forests. Conclusions Liana biomass distribution and tree infestation vary significantly with elevation. Biomass of lianas and relative contribution of lianas to total above-ground biomass both decrease with elevation. Topographic effects likely result from higher soil fertility at lower slope positions. [ABSTRACT FROM AUTHOR]

Ridges of tropical mountains often differ strikingly from neighbouring ravines in terms of forest structure, productivity and species composition. This heterogeneity is poorly understood despite its critical role in biodiversity maintenance, carbon and nutrient budgets., We examined measures of tree biomass and productivity, foliage and litter quality (nutrient concentrations, specific leaf mass, phenolics), herbivory and leaf litter decomposition in each six plots laid out in upper and lower slope position in a tropical montane moist forest in southeastern Ecuador., Productivity, quality of foliage and litter as well as herbivory were significantly lower in upper slope position, and closely correlated with soil nutrient concentrations and accumulated humus. The decomposition of upper slope leaf litter (decomposition rate k) was substantially lower than in litter from lower slope forest, whereas the site of decomposition (slope position) only had a marginal effect on the decomposition rate., Our results suggest that the differences in stand structure, productivity, foliar quality, herbivory and decomposition between slope positions are ultimately due to stronger nutrient limitations in upper slope forest. We propose a general conceptual model that explains origin and maintenance of contrasting forest types along topographical gradients through down-slope fluxes of nutrients and water, and a nutrient-driven positive feedback cycle. [ABSTRACT FROM AUTHOR]

Increased nitrogen (N) depositions expected in the future endanger the diversity and stability of ecosystems primarily limited by N, but also often co-limited by other nutrients like phosphorus (P). In this context a nutrient manipulation experiment (NUMEX) was set up in a tropical montane rainforest in southern Ecuador, an area identified as biodiversity hotspot. We examined impacts of elevated N and P availability on arbuscular mycorrhizal fungi (AMF), a group of obligate biotrophic plant symbionts with an important role in soil nutrient cycles. We tested the hypothesis that increased nutrient availability will reduce AMF abundance, reduce species richness and shift the AMF community toward lineages previously shown to be favored by fertilized conditions. NUMEX was designed as a full factorial randomized block design. Soil cores were taken after 2 years of nutrient additions in plots located at 2000 m above sea level. Roots were extracted and intraradical AMF abundance determined microscopically; the AMF community was analyzed by 454-pyrosequencing targeting the large subunit rDNA. We identified 74 operational taxonomic units (OTUs) with a large proportion of Diversisporales. N additions provoked a significant decrease in intraradical abundance, whereas AMF richness was reduced significantly by N and P additions, with the strongest effect in the combined treatment (39% fewer OTUs), mainly influencing rare species. We identified a differential effect on phylogenetic groups, with Diversisporales richness mainly reduced by N additions in contrast to Glomerales highly significantly affected solely by P. Regarding AMF community structure, we observed a compositional shift when analyzing presence/absence data following P additions. In conclusion, N and P additions in this ecosystem affect AMF abundance, but especially AMF species richness; these changes might influence plant community composition and productivity and by that various ecosystem processes. [ABSTRACT FROM AUTHOR]

The species richness-productivity relationship ( SRPR), by which the species richness of habitats or ecosystems is related to the productivity of the ecosystem or the taxon, has been documented both on regional and local scales, but its generality, biological meaning and underlying mechanisms remain debated., We evaluated the SRPR and three mechanistic hypotheses using terrestrial ferns in 18 study plots along an elevational gradient (500-4000 m) in Ecuador. We measured annual increases in above-ground biomass of 6175 fern individuals from 91 species over 2 years, and estimated plot-level tree productivity from increases in above-ground woody biomass of 560 trees. Analyses were conducted by (i) comparing plots along the elevational gradient (regional scale) and (ii) comparing plots within each elevational belt (local scale)., Fern diversity was related to the productivity of the fern assemblages, but not to above-ground productivity of the trees. At the regional scale, we found a positive relationship of fern species richness to fern productivity that appeared to be determined by an increase in the number of fern individuals and niche availability. In contrast, at the local scale, this relationship was negative and likely driven by interspecific competition., Synthesis. Plot diversity of ferns appears to be limited by the number of available niches and competition to occupy these niches. At the local scale, this is reflected in a negative SRPR probably driven by competition, whereas with increasing scale, the positive influence of productivity emerges. This represents the first evidence that productivity and competition affect the diversity of tropical herb assemblages at the plot scale. [ABSTRACT FROM AUTHOR]

Questions To assess the relationship between modern pollen rain and Andean montane forest vegetation for diversity, and provide a basis for interpretations of palaeoecological data in the northern Andes, we asked: (1) can the reduction of plant and pollen data to family level preserve information about diversity in both data sets; (2) how precisely do tree pollen and spore types represent richness patterns along an altitudinal gradient on tropical mountains; and (3) how similar are tree pollen and spore family richness in relationship to tree family richness? Location Tropical montane rain forests, Podocarpus National Park in the Andes of South Ecuador (3°S, 79°W, 1000-3000 m a.s.l.). Methods We analysed tree diversity and species composition in three different rain forest types: Premontane ( PMF), lower montane ( LMF) and upper montane ( UMF). We investigated modern pollen rain using pollen traps. After testing the reliability of a taxonomic surrogacy on the plant data, we compared abundance and representation, as well as diversity of the two data sets at family level. This was done using rarefaction and Sørensen indices. Results The correlation between tree species and families was high ( r = 0.81, P < 0.001). Sample rarefaction on tree pollen and plant family data revealed highest pollen diversity on sites of the UMF, but highest tree diversity on LMF and PMF sites. The Sørensen indices indicate down-drift of pollen from higher altitudes in PMF and LMF and up-drift in UMF. Between 1% and 50% of pollen taxa of each sample originate from outside the plot. Conclusions Taxonomic surrogacy at family level is a good tool for comparing presence-absence patterns of plant and pollen data in tropical regions with high tree diversity. On a family basis, pollen presence-absence data represent the corresponding tree vegetation data, but uncertainties increase with decreasing altitude. The higher diversity in pollen data of the UMF, but slightly lower diversity in the LMF and PMF, can at least partly be explained by wind patterns, local abundance of shrubs and herbs and differences in evenness. [ABSTRACT FROM AUTHOR]

The tropical montane forests of the E Andean cordillera in Ecuador receive episodic Sahara-dust inputs particularly increasing Ca deposition. We added CaCl2 to isolate the effect of Ca deposition by Sahara dust to tropical montane forest from the simultaneously occurring pH effect. We examined components of the Ca cycle at four control plots and four plots with added Ca (2 × 5 kg ha-1 Ca annually as CaCl2) in a random arrangement. Between August 2007 and December 2009 (four applications of Ca), we determined Ca concentrations and fluxes in litter leachate, mineral soil solution (0.15 and 0.30 m depths), throughfall, and fine litterfall and Al concentrations and speciation in soil solutions. After 1 y of Ca addition, we assessed fine-root biomass, leaf area, and tree growth. Only < 3% of the applied Ca leached below the acid organic layer (pH 3.5-4.8). The added CaCl2 did not change electrical conductivity in the root zone after 2 y. In the second year of fertilization, Ca retention in the canopy of the Ca treatment tended to decrease relative to the control. After 2 y, 21% of the applied Ca was recycled to soil with throughfall and litterfall. One year after the first Ca addition, fine-root biomass had decreased significantly. Decreasing fine-root biomass might be attributed to a direct or an indirect beneficial effect of Ca on the soil decomposer community. Because of almost complete association of Al with dissolved organic matter and high free Ca2+ : Al3+ activity ratios in solution of all plots, Al toxicity was unlikely. We conclude that the added Ca was retained in the system and had beneficial effects on some plants. [ABSTRACT FROM AUTHOR]

A growing body of observational and theoretical evidence points toward the importance of clouds in the atmospheres of ultra-cool brown dwarfs and giant planets. Empirically, the presence of clouds is inferred from the red, likely dusty atmospheres of young substellar objects, and from detections of periodic variability in a fraction of brown dwarfs - as expected from rotation and a patchy cloud cover. Theoretical models have progressed alongside by including ever more comprehensive atomic and molecular opacity tables, incorporating the treatment of non-equilibrium chemistry and clouds through vertical mixing and grain size/sedimentation parameters, and employing 3-D hydrodynamical simulations. In this proceeding we summarize the key issues raised during the first gathering of observers and theorists to discuss clouds and atmospheric circulation in non-irradiated ultra-cool dwarfs and giant planets. (© 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]

Low-income Latino immigrants are understudied in elder abuse research. Limited English proficiency, economic insecurity, neighborhood seclusion, a tradition of resolving conflicts within the family, and mistrust of authorities may impede survey research and suppress abuse reporting. To overcome these barriers, promotores, local Spanish-speaking Latinos, were recruited and trained to interview a sample of Latino adults aged 66 and older residing in low-income communities. The promotores conducted door-to-door interviews in randomly selected census tracts in Los Angeles to assess the frequency of psychological, physical, and sexual abuse; financial exploitation; and caregiver neglect. Overall, 40.4% of elderly Latino adults had experienced some form of abuse or neglect within the previous year. Nearly 25% reported psychological abuse, 10.7% physical assault, 9% sexual abuse, and 16.7% financial exploitation, and 11.7% were neglected by their caregivers. Younger age, higher education, and experiencing sexual or physical abuse before age 65 were significant risk factors for psychological, physical, and sexual abuse. Years lived in the United States, younger age, and prior abuse were associated with greater risk of financial exploitation. Years spent living in the United States was a significant risk factor for caregiver neglect. Abuse prevalence was much higher in all mistreatment domains than findings from previous research on community-dwelling elderly adults, suggesting that low-income Latino immigrants are highly vulnerable to elder mistreatment or that respondents are more willing to disclose abuse to promotores who represent their culture and community. [ABSTRACT FROM AUTHOR]

Tropical forests are important sources of the greenhouse gas nitrous oxide (N2O) and of nitric oxide (NO), a precursor of ozone. In tropical montane forests nitrogen limitation is common which affects both soil N2O and NO fluxes and forest productivity. Here we present evidence that forest productivity and N-oxide (N2O + NO) fluxes are linked through N availability along elevation and topographic gradients in tropical montane forests. We measured N-oxide fluxes, several indices of N availability, and forest productivity along an elevation gradient from 1000 m to 3000 m and along topographic gradients. Organic layer thickness of the soils increased and N availability decreased with increasing elevation and along the topographic gradient from the lower slope position to the ridges. Annual N2O fluxes ranged from -0.53 μg(N)m-2h-1 to 14.54 μg(N)m-2h-1 while NO fluxes ranged from -0.02 μg(N)m-2h1 to 1.13 μg(N)m-2h-1. Both N-oxide fluxes and forest productivity increased with increasing N availability and showed close positive correlations with indices of N availability (C/N ratio and δ 15N signature of litterfall). We interpret the close correlations of N-oxide fluxes with total litterfall and tree basal area increment as evidence that N availability links N-oxide fluxes and forest productivity. This opens the possibility to include forest productivity as co-variable in predictions of Noxide fluxes in nitrogen limited tropical montane forests. Especially increment of tree basal area was a promising proxy to predict soil N-oxide fluxes in these N limited ecosystems, possibly because it better reflects long-term forest productivity than total litterfall. [ABSTRACT FROM AUTHOR]

We studied the spatial heterogeneity of tree diversity, and of forest structure and productivity in a highly diverse tropical mountain area in southern Ecuador with the aim of understanding the causes of the large variation in these parameters. Two major environmental gradients, elevation and topography, representing a broad range of climatic and edaphic site conditions, were analyzed. We found the highest species richness of trees in valleys <2100 m. Valleys showed highest values of basal area, leaf area index and tree basal area increment as well. Tree diversity also increased from ridges to valleys, while canopy openness decreased. Significant relationships existed between tree diversity and soil parameters (pH, total contents of Mg, K, Ca, N and P), and between diversity and the spatial variability of pH and Ca and Mg contents suggesting a dependence of tree diversity on both absolute levels and on the small-scale heterogeneity of soil nutrient availability. Tree diversity and basal area increment were positively correlated, partly because both are similarly affected by soil conditions. We conclude that the extraordinarily high tree species richness in the area is primarily caused by three factors: (1) the existence of steep altitudinal and topographic gradients in a rather limited area creating a small-scale mosaic of edaphically different habitats; (2) the intermingling of Amazonian lowland plant species, that reach their upper distribution limits, and of montane forest species; and (3) the geographical position of the study area between the humid eastern Andean slope and the dry interandean forests of South Ecuador. [ABSTRACT FROM AUTHOR]

The 2007 DARPA Urban Challenge afforded the golden opportunity for the Technische Universität Braunschweig to demonstrate its abilities to develop an autonomously driving vehicle to compete with the world's best. After several stages of qualification, our team CarOLO qualified early for the DARPA Urban Challenge Final Event and was among only 11 teams from initially 89 competitors to compete in the final. We had the ability to work together in a large group of experts, each contributing his expertise in his discipline, and significant organizational, financial, and technical support by local sponsors, who helped us to become the best non-U.S. team. In this report, we describe the 2007 DARPA Urban Challenge, our contribution, “Caroline,” the technology, and algorithms, along with her performance in the DARPA Urban Challenge Final Event on November 3, 2007. © 2008 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

• Three members of the Nyctaginaceae, twoNeeaspecies and oneGuapiraspecies, occurred scattered within a very species-rich neotropical mountain rain forest. The three species were found to form ectomycorrhizas of very distinctive characters, while all other tree species examined formed arbuscular mycorrhizas.• The ectomycorrhizas were structurally typified according to light and transmission electron microscope investigations. The internal transcribed spacer (ITS) rDNA and part of the nuclear large subunit (LSU, 28S) rDNA of the mycorrhiza forming fungi were amplified and sequenced. Phylogenetic analyses were carried out.• Neeaspecies 1 was found to form typical ectomycorrhizas with five different fungal species,Russula puiggarii,Lactariussp., twoTomentellaorThelephoraspecies, and one ascomycete.Neeaspecies 2 and theGuapiraspecies were associated with only one fungus each, aTomentella/Thelephoraspecies clustering closely together in an ITS-neighbour-joining tree. The long and fine rootlets of theGuapiraspecies showed proximally a hyphal mantle and a Hartig net, but distally intracellular fungal colonization of the epidermis and root hair development. The ectomycorrhizal segments of the long roots ofNeeaspecies 2 displayed a hyphal mantle and a Hartig net around alive root-hair-like outgrowths of the epidermal cells.• The distribution and the evolution of ectomycorrhizas in the predominantly neotropic Nyctaginaceae are discussed.New Phytologist(2004)doi: 10.1111/j.1469-8137.2004.01284.x© New Phytologist(2004) [ABSTRACT FROM AUTHOR]

Abstract. Turnover in species composition of the extremely species-rich family Geometridae (Lepidoptera) was investigated along an elevational gradient ranging from 1040 m to 2677 m above sea level. Moths were sampled using weak light traps (30 W) in three field periods in 1999 and 2000 in an Andean montane rainforest in the province of Zamora-Chinchipe in southern Ecuador. A total of 13 938 specimens representing 1010 species were analysed. Similarities of ensembles of all geometrid moths and of the subfamilies Ennominae and Larentiinae were calculated using the NESS index (with m [sub max] ). Ordinations performed using nonmetric multidimensional scaling (NMDS) and correspondence analysis depicted a gradual change of the ensembles along the altitudinal gradient. Extracted ordination scores significantly correlate with altitude (-0.97 ≤ r ≤ -0.95, P < 0.001) and with ambient air temperature (0.93 ≤ r ≤ 0.97, P < 0.001). Temperature is therefore assumed to be the most important abiotic determinant responsible for the species turnover among the moths. Matrix correlation tests were performed in order to compare faunal matrices with matrices derived from available environmental factors. Both tree diversity and vegetation structure significantly correlate with faunal data, but tree diversity explains considerably more of the data variability (range: Mantel r = 0.81–0.83, P < 0.001) than vegetation structure (range: Mantel r = 0.35, P < 0.005 to r = 0.43, P < 0.001). Tree diversity also changes gradually and scores of the first NMDS dimension are highly significantly correlated with altitude (r = 0.98, P < 0.001). A common underlying factor such as ambient temperature might also be responsible for such vegetation changes. Additionally, simulated model data was developed that assumed a constant turnover of moth species and equal elevational ranges of all species involved. Despite the simplicity of the models, they fit empirical data very well (Mantel r > 0.80 and P < 0.001 in all models). [ABSTRACT FROM AUTHOR]