Bird species present in urban parks are more colorful than urban avoiders:A test in the Argentinian Pampas

Bird plumage color has been assessed as a possible trait driving the presence of bird species in urban areas.Although some species can see the ultraviolet(UV) spectrum,the mentioned studies did not take into account UV reflectance when characterizing bird plumage.This study aimed to use a recent database of the colorfulness in passerines that incorporated the UV spectrum to compare bird colorfulness and other traits between urban parks and rural areas in Central-East Argentina.Birds in urban parks were surveyed in 51 parks in 6 cities during breeding and non-breeding seasons.A list of Passeriformes species from parks was created,and a list of urban avoider species was created from the bibliography.Species traits were body mass,clutch size,migratory status,nesting site,diet and habitat breadth,and plumage colorfulness.A total of 85 species were detected in the regional pool,of which 30 species were detected in urban parks.Bird species present in urban parks were more colorful than bird species only present in rural areas.In addition,bird presence in urban parks was positively related to their regional frequency and diet breadth.Moreover,urban presence was related to nesting on trees and buildings,whereas species not present in urban parks nested on the ground.The results obtained showed that bird color is significantly associated with presence of bird species in urban parks.

Tri-axial accelerometry allows to determine parental food provisioning behaviour in a marine bird

The study of parental food provisioning is essential for understanding the breeding ecology of birds.We conducted the first study using accelerometry to detect food provisioning in birds,using Support Vector Machine(SVM)models to identify when adults feed chicks of three different age classes.Accelerometers were attached to the head of adult female Imperial Shags(Leucocarbo atriceps),and various attributes derived from the acceleration signals were used to train SVM models for each chick age class.Model performance improved with chick age class,with SVM models achieving high overall accuracy(>88%)and highest sensitivity in older chick categories(>91%).However,precision values,especially for younger chicks,remained relatively low(between 26%and 45%).The application of a time filter based on the minimum duration of the observed food provisioning behaviours for each chick age category,improved model performance by reducing false provisioning behaviours,particularly in the model for older chicks,which showed the highest precision(72.4%).This study highlights the effectiveness of accelerometry and machine learning in studying parental food provisioning in birds,providing a rapid and accurate data collection method to complement traditional techniques.The described methodology can be applied to any bird species that exhibits distinctive movements while feeding its offspring and has suitable characteristics for attaching an accelerometer to the body part that best captures this movement.Finally,it is hoped that the results of this study will contribute to future research on key questions in parental investment theory and reproductive strategies in birds.

Regional brain susceptibility to neurodegeneration: what is the role of glial cells?

The main pathological feature of the neurodegenerative diseases is represented by neuronal death that represents the final step of a cascade of adverse/hostile events.Early in the neurodegenerative process,glial cells (including astrocytes,microglial cells,and oligodendrocytes) activate and trigger an insidious neuroinflammatory reaction,metabolic decay,blood brain barrier dysfunction and energy impairment,boosting neuronal death.How these mechanisms might induce selective neuronal death in specific brain areas are far from being elucidated.The last two decades of neurobiological studies have provided evidence of the main role of glial cells in most of the processes of the central nervous system,from development to synaptogenesis,neuronal homeostasis and integration into,highly specific neuro-glial networks.In this mini-review,we moved from in vitro and in vivo models of neurodegeneration to analyze the putative role of glial cells in the early mechanisms of neurodegeneration.We report changes of transcriptional,genetic,morphological,and metabolic activity in astrocytes and microglial cells in specific brain areas before neuronal degeneration,providing evidence in experimental models of neurodegenerative disorders,including Parkinson’s and Alzheimer’s diseases.Understanding these mechanisms might increase the insight of these processes and pave the way for new specific glia-targeted therapeutic strategies for neurodegenerative disorders.

Microbial oxidation of refractory gold sulfide concentrate by a native consortium

A defined mesophilic consortium including an iron oxidizing bacterium and a sulfur oxidizing bacterium was constructed to evaluate its ability for bioleaching a flotation concentrate from Andacollo mine in Neuquén,Argentina.Experiments were performed in shake flasks with a pulp density of10%(w/v),using a basal salt medium containing ferrous iron at pH1.8.The leaching solutions were analyzed for pH,redox potential(using specifics electrodes),ferrous iron(by UV-Vis spectrophotometry)and metal concentrations(by atomic absorption spectroscopy).The results showed that the consortium was able to reduce the refractory behavior of the concentrate,allowing91.6%of gold recovery;at the same time,high dissolution of copper and zinc was reached.These dissolutions followed a shrinking core kinetic model.According to this model,the copper solubilization was controlled by diffusion through a product layer(mainly jarosite),while zinc dissolution did not show a defined control step.This designed consortium,composed of bacterial strains with specific physiological abilities,could be useful not only to optimize gold recovery but also to decrease the leachates metallic charge,which would be an environmental advantage.

Validation of a SPME-GC Method for Azoxystrobin and Pyraclostrobin in Blueberries, and Their Degradation Kinetics

Analytical method for the residues of strobilurins azoxystrobin and pyraclostrobin in blueberries was developed. Fungicide residues were determined by solid-phase microextraction (SPME) cou-pled to gas chromatography with micro-electron capture detector. The effect of pH values and fiber coatings were studied. The SPME fiber coating selected was 100 μm PDMS. The method is selective with adequate precision and high accuracy and sensitivity. Recoveries ranged within the 100% - 106% range for azoxystrobin, and 96% - 106% range for pyraclostrobin;and detection and quantification limits were 2.0 and 6.0 μg/kg for azoxystrobin, and 26.0 and 86.0 μg/kg for py-raclostrobin, respectively. Statistical parameters indicated the occurrence of matrix effect;con-sequently calibration was performed on spiked samples. Degradation of azoxystrobin and pyra-clostrobin was studied in blueberry fields located in Concordia, Argentina, with fruits from Emerald and Jewel varieties. The degradation of these fungicides in both blueberry varieties studied followed a first order rate kinetics, and the half-life for azoxystrobin was 11.6 and 17.8 days for Emerald and Jewel cultivars;and for pyraclostrobin was 5.5 and 8.0 days, respectively.

CD4+ T cells and natural killer cells: Biomarkers for hepatic fibrosis in human immunodeficiency virus/hepatitis C virus-coinfected patients

AIM To characterize peripheral blood natural killer(NK) cells phenotypes by flow cytometry as potential biomarker of liver fibrosis in human immunodeficiency virus(HIV)/hepatitis C virus(HCV) coinfected patients.METHODS Peripheral mononuclear cells from 24 HIV/HCV(HBVnegative) coinfected and 5 HIV/HCV/HBV seronegative individuals were evaluated. HIV/HCV coinfected patients were divided in to groups: G1, patients with METAVIR F0-F2 and G2, patients with METAVIR F3-F4. NK surface cell staining was performed with: AntiCD3(APC/Cy7), anti-CD56(PE/Cy5), anti-CD57(APC), anti-CD25(PE), anti-CD69(FITC), anti-NKp30(PE), antiNKp46(PE/Cy7), anti-NKG2D(APC), anti-DNAM(FITC); anti-CD62L(PE/Cy7), anti-CCR7(PE), anti-TRAIL(PE), anti-Fas L(PE), anti CD94(FITC). Flow cytometry data acquisition was performed on BD FACSCanto, analyzed using Flow Jo software. Frequency of fluorescence was analyzed for all single markers. Clinical records were reviewed, and epidemiological and clinical data were obtained.RESULTS Samples from 11 patients were included in G1 and from 13 in G2. All patients were on ARV, with undetectable HIV viral load. Liver fibrosis was evaluated by transient elastography in 90% of the patients and with biopsy in 10% of the patients. Mean HCV viral load was(6.18 ± 0.7 log10). Even though, no major significant differences were observed between G1 and G2 regarding NK surface markers, it was found that patients with higher liver fibrosis presented statistically lower percentage of NK cells than individual with low to mild fibrosis and healthy controls(G2: 5.4% ± 2.3%, G1: 12.6% ± 8.2%, P = 0.002 and healthy controls 12.2% ± 2.7%, P = 0.008). It was also found that individuals with higher liver fibrosis presented lower CD4 LT count than those from G1(G2: 521 ± 312 cells/μL, G1: 770 ± 205 cells/μL; P = 0.035).CONCLUSION Higher levels of liver fibrosis were associated with lower percentage of NK cells and LTCD4+ count; and they may serve as noninvasive biomarkers of liver damage.

Cenozoic basin evolution of the Central Patagonian Andes:Evidence from geochronology, stratigraphy, and geochemistry

The Central Patagonian Andes is a particular segment of the Andean Cordillera that has been subjected to the subduction of two spreading ridges during Eocene and Neogene times. In order to understand the Cenozoic geologic evolution of the Central Patagonian Andes, we carried out geochronologic(U-Pb and^(40)Ar/^(39)Ar), provenance, stratigraphic, sedimentologic, and geochemical studies on the sedimentary and volcanic Cenozoic deposits that crop out in the Meseta Guadal and Chile Chico areas(～47°S). Our data indicate the presence of a nearly complete Cenozoic record, which refutes previous interpretations of a hiatus during the middle Eocene-late Oligocene in the Central Patagonian Andes. Our study suggests that the fluvial strata of the Ligorio Marquez Formation and the flood basalts of the Basaltos Inferiores de la Meseta Chile Chico Formation were deposited in an extensional setting related to the subduction of the Aluk-Farallon spreading ridge during the late Paleocene-Eocene. Geochemical data on volcanic rocks interbedded with fluvial strata of the San Jose Formation suggest that this unit was deposited in an extensional setting during the middle Eocene to late Oligocene. Progressive crustal thinning allowed the transgression of marine waters of Atlantic origin and deposition of the upper Oligocene-lower Miocene Guadal Formation. The fluvial synorogenic strata of the Santa Cruz Formation were deposited as a consequence of an important phase of compressive deformation and Andean uplift during the early-middle Miocene. Finally, alkali flood basalts of the late middle to late Miocene Basaltos Superiores de la Meseta Chile Chico Formation were extruded in the area in response to the suduction of the Chile Ridge under an extensional regime. Our studies indicate that the tectonic evolution of the Central Patagonian Andes is similar to that of the North Patagonian Andes and appears to differ from that of the Southern Patagonian Andes, which is thought to have been the subject of continuous compressive deformation since the late Early Cretaceous.

Alterations of Endogenous Hormonal Levels in Plants under Drought and Salinity

The phytohormones are pivotal chemical messengers produced within the plant that regulate its growth and development, and responses to environmental stimuli. Drought and salinity are adverse environmental factors that disturb the plant hormonal balance. Accordingly, these hormonal fluctuations modify the cellular dynamic and hence they play a central role in regulating plant growth responses to abiotic stresses such as drought and salinity. The present review gives an update about the alterations of endogenous phytohormones such as abscisic acid (ABA), auxins (Aux), cytokinins (CKs), ethylene (ET), gibberellins (GAs), jasmonates (JAs), salicylic acid (SA), brassinosteroids (BRs), strigolactones (SLs) and nitric oxide (NO) that occur as part of the adaptative responses of plant against drought and salt stresses. Better understanding of the endogenous hormonal changes during the plant response to both abiotic stresses will contribute, in part, to the development of stress-tolerant plants.

Influence of pile-up on nanoindentation measurements in Cu-2wt.%Be samples with precipitates

The influence of pile-up on the nanoindentation measurements in Cu 2wt.%Be samples with precipitates was carefully studied.The precipitates were formed by aging treatments for 1 h at different temperatures between 540 and 680 K.The load depth curves were analyzed using the classical Oliver and Pharr method,and the obtained elastic modulus and hardness were compared with values estimated by other techniques.An important level of pile-up was found in samples with precipitates and differences in the load depth curves were observed between the unaged and aged samples.A correction of the contact depth considering the pile-up proposed by Loubet was used for hardness estimation.For the determination of the elastic modulus,an approach based on the relation between the ratio of unloading work to indentation total work,with the ratio H/Er(H is the hardness;Er is the reduced modulus),was employed.A specific relation between both parameters was developed.

Seasonal influence and local factors affecting macroinvertebrate structure in a high-altitude Andean stream

Small water bodies are critical for maintaining freshwater biodiversity,but are among the least investigated aquatic environments.We examined physical and chemical variables at two reaches in Arroyo Tambillos,a small,high-elevation Andean stream,in NW Mendoza province,Argentina,across four seasons to examine how local factors and seasonality affected the structure of the macroinvertebrate community.The Arroyo Tambillos community was numerically dominated by ephemeropterans(mainly Massartellopsis irarrazavali)while the dipteran Chironomidae were the most species rich.Total macroinvertebrate abundance was highest in summer,driven mainly by taxa that were secondary in dominance(Austrelmis sp.and Andesiops peruvianus),while richness did not differ between seasons.However,benthic composition was different in Fall 2013(March)compared to other seasons,largely because of the increased abundance of Chironomidae.Canonical correspondence analysis discriminated Chironomidae species distributions in Fall 2013 by substrate type(i.e.,big and small boulder substrate).By contrast,discharge,velocity,and depth were the variables which most affected the macroinvertebrate abundance and distributions.Contrary to our expectations,most community changes observed occurred in fall instead of summer.Nivo-kryal stream communities like the one described here have become increasingly important for conserving mountain stream biodiversity as anthropogentic impacts and climate change increasingly impact lower stream reaches.Therefore,monitoring high-altitude streams like the Arroyo Tambillos may be critical for preventing the future loss of unique and sensitive stream biota.

Stripe of normal mechanisms for crustal earthquakes with M ≤ 3.5 flanking the western side of the thrust front zone in the Andes backarc

Earthquakes with magnitudes M ≤ 3.5 were registered in the Andes backarc between ~32.5°S 33.75°S within a temporary experiment from November 2002 to March 2003. Data were collected from 15 seismological broad band stations, deployed above flat subduction section and also above the transitional to normal section of the Nazca plate. Seismic events were located mostly in part of the Southern Precordillera and Cerrilladas Pedemontanas of Mendoza Province. Focal mechanism solutions were obtained, for selected data between15 kmand35 kmdepths, from P wave first motion using FOCMEC software. A band trending NW-NNW of normal focal mechanism earthquakes is located just by the thrust front towards West, and covers the Southern tip of the Southern Precordillera and the Western side of the Cerrilladas Pedemontanas, Mendoza Province, Argentina. Thrust focal mechanism solutions obtained in the present work for events with magnitude less than or equal to 3.5 also show that the thrust front South of ~33.1°S is located in the same place as Mw ≥ 3.6 earthquakes. The most significant findings in this work are these signals of extensional regimen which appear in a compressional subduction tectonic regimen. Nevertheless the short temporal experiment precludes firm interpretations about this particular phenomenon. Probably it is related to a temporary stress relaxation. The normal earthquakes are likely associated to normal faults, and/or to their subsidiaries, that were inverted by contraction and now re-inverted at least transitorily as normal. These faults, which are near and to the East of the suture between Chilenia and Cuyania Paleozoic terranes, were originally involved in the Cuyo Triassic basin formation.

The Hsp90-binding immunophilin FKBP52 enhances neurodifferentiation and neuroregeneration in murine models

The term immunophilin involves a family of proteins whose domain shows peptidylprolyl-(cis/trans)-isomerase (PPIase)enzymatic activity,i.e., the reversible cis/trans interconversion of Xaa-Pro bonds (Annett et al.,2020).The PPlase domain of these proteins usually binds to immunosuppressive drugs,such as the macrolide FK506 (referred to as the FKBP subfamily) or the cyclic undecapeptide cyclosporine A (called CyP subfamily).

New insights into petrogenesis of Miocene magmatism associated with porphyry copper deposits of the Andean Pampean flat slab,Argentina

The Paramillos de Uspallata mining district located in the backarc region of the Pampean flat-slab segment(28°-33°S) features porphyry-type deposits genetically associated with Middle Miocene volcanics. This mineralizing magmatism comprising hydrothermally altered(sodic-calcic, potassic and phyllic alteration) subvolcanic and pyroclastic rocks of andesite-basaltic andesite and dacite-rhyolite composition with a typical arc signature, represents the eastward broadening of the Farellones arc by ~17 Ma. Its geochemistry also reveals a residual mineralogy of amphibole ± garnet with limited plagioclase fractionation resulting in an adakitic signal; however, according to the isotopic data collected in our study, the contributions of MASH(melting-assimilation-storage-homogenization) processes in the acquisition of this signal cannot be disregarded.Both the broadening of the Farellones arc and its residual mineralogy e typical of relatively deep magmatic chambers e are consistent with a slab shallowing and outcoming crustal thickening setting.This tectonic scenario could be interpreted as a result of an early effect of the Juan Fernandez Ridge collision that was further to the north by ~17 Ma. Our findings suggest that magmas were fertile for porphyry type deposits during the early stages of the slab shallowing.

Fungal Decay, Coating, Burning Properties and Change of Color of Particleboards Manufactured with Woody Biomass, Agricultural Wastes and Tetra Pak Residues

Lignocellulosic residues resulting from agricultural activities and urban centers cause pollution. A possible solution to this problem is to combine these residues with woody plants to produce particleboards. The purpose of this study was to evaluate decay resistance, coating and burning properties and the change of color caused by accelerated weathering of particleboards manufactured with a combination of 3 woody species used for commercial reforestation in tropical areas (Cupressus lusitanica, Gmelina arborea and Tectona grandis), pineapple (Ananas comosus) leaves from the crown and the plant (PL), empty fruit bunch of Elaeis guineensis (EBF) and tetra pak packages (TP). According to the results, the mixtures of T. grandis and EFB were classified as moderately resistant and other mixtures (woody species and PL or TP) were classified as slightly resistant. The finish performance test determined that the mixtures with TP presented the best performance, followed by the mixtures with oil palm components and the mixtures composed of pineapple leaves. Regarding lacquer consumption, no differences were found between the mixtures. The combustion test determined that particleboards with TP and EFB showed the highest resistance to combustion, while pineapple presented the lowest resistances to combustion. In the accelerated weathering exposure test, the mixtures of the three species with TP showed the best performance in accelerated weathering. Contrariwise, the mixtures with pineapple leaves showed the lowest resistance to accelerated weathering. Oil palm particleboards presented lower resistance to weathering than TP, though higher than pineapple leaves’ resistance.

How much has the Sun influenced Northern Hemisphere temperature trends?An ongoing debate

In order to evaluate how much Total Solar Irradiance(TSI)has influenced Northern Hemisphere surface air temperature trends,it is important to have reliable estimates of both quantities.Sixteen different estimates of the changes in TSI since at least the 19th century were compiled from the literature.Half of these estimates are"low variability"and half are"high variability".Meanwhile,five largely-independent methods for estimating Northern Hemisphere temperature trends were evaluated using:1)only rural weather stations;2)all available stations whether urban or rural(the standard approach);3)only sea surface temperatures;4)tree-ring widths as temperature proxies;5)glacier length records as temperature proxies.The standard estimates which use urban as well as rural stations were somewhat anomalous as they implied a much greater warming in recent decades than the other estimates,suggesting that urbanization bias might still be a problem in current global temperature datasets-despite the conclusions of some earlier studies.Nonetheless,all five estimates confirm that it is currently warmer than the late 19th century,i.e.,there has been some"global warming"since the 19th century.For each of the five estimates of Northern Hemisphere temperatures,the contribution from direct solar forcing for all sixteen estimates of TSI was evaluated using simple linear least-squares fitting.The role of human activity on recent warming was then calculated by fitting the residuals to the UN IPCC’s recommended"anthropogenic forcings"time series.For all five Northern Hemisphere temperature series,different TSI estimates suggest everything from no role for the Sun in recent decades(implying that recent global warming is mostly human-caused)to most of the recent global warming being due to changes in solar activity(that is,that recent global warming is mostly natural).It appears that previous studies(including the most recent IPCC reports)which had prematurely concluded the former,had done so because they failed to adequately consider all the relevant estimates of TSI and/or to satisfactorily address the uncertainties still associated with Northern Hemisphere temperature trend estimates.Therefore,several recommendations on how the scientific community can more satisfactorily resolve these issues are provided.

A Kinetic Model for Describing the Effect of Proteins on the Air-Water Interface Tension

The main objective of this work was to develop a kinetic model to describe the variation of the surface tension in an air-water interface due to the adsorption of proteins from different origins and to identify quantitatively the relevant parameters, it was considered that the processes of adsorption, unfolding and reordering of the protein molecule in the interface occur simultaneously. The model used in the present work to calculate the surface tension postulates the existence of two simultaneous processes, adsorption and protein rearrangement represented with an equation of first order with two exponential components. The relevant parameter of the equation are ka and kr-the rate constants of the two first order kinetic phases that correspond to both conformational states of the protein, adsorption and rearrangement during the process of variation of the surface tension, and the amplitude parameters Aa and Ar. The results suggest that the kinetic model for the variation of the surface tension of protein solutions proposed in this work, with two simultaneous first order processes, is more appropriate than previous models to describe such variation.

Biological Corridors as a Connectivity Tool in the Region of the Great American Chaco:Identification of Biodiversity Hotspots in the Ecoregions of the Paraguayan Chaco

This work presents the main biodiversity hotspots existing in the Paraguayan Chaco and is an update of the results obtained in the first Ecoregional Assessment of the Great American Chaco.These are the results of a series of workshops that included scientific and technical discussions carried out by local experts in zoology,botany,forestry,soil science,and hydrogeology applying a biodiversity vision of 25-30 years for the territory,after overlapping the maps of the first assessment with that of the advance of the changes of land use in the territory.Criteria for detecting biodiversity hotspots were discussed,including:permanent and temporary watercourses,other bodies of water such as fresh and salty lagoons,reserve areas of different categories,as well as important bird areas(IBAs),RAMSAR areas and others,which must be connected in the future,combining the production areas with the conservation of biodiversity.

Challenges in the Detection and Attribution of Northern Hemisphere Surface Temperature Trends Since 1850

Since 2007,the Intergovernmental Panel on Climate Change(IPCC)has heavily relied on the comparison between global climate model hindcasts and global surface temperature(ST)estimates for concluding that post-1950s global warming is mostly human-caused.In Connolly et al.,we cautioned that this approach to the detection and attribution of climate change was highly dependent on the choice of Total Solar Irradiance(TSI)and ST data sets.We compiled 16 TSI and five ST data sets and found by altering the choice of TSI or ST,one could(prematurely)conclude anything from the warming being“mostly human-caused”to“mostly natural.”Richardson and Benestad suggested our analysis was“erroneous”and“flawed”because we did not use a multilinear regression.They argued that applying a multilinear regression to one of the five ST series re-affirmed the IPCC's attribution statement.They also objected that many of the published TSI data sets were out-of-date.However,here we show that when applying multilinear regression analysis to an expanded and updated data set of 27 TSI series,the original conclusions of Connolly et al.are confirmed for all five ST data sets.Therefore,it is still unclear whether the observed warming is mostly human-caused,mostly natural or some combination of both.

Geomechanical model for a seismically active geothermal field:Insights from the Tinguiririca volcanic-hydrothermal system

In this work,we develop a multidisciplinary approach to investigate a geothermal system located at the volcanic arc of a subduction-related orogen and highlight the interplay between active tectonism.stress field and fluid migration.By using results of field investigations from the Tinguiririca geothermal field in the High Andes of Chile(35°S),empirical analysis,and numerical models of static stress variations,we proposed a geomechanical model for evaluating the distribution of hydrothermal manifestations in a seismically-active region.The present geomechanical model follows four major steps:(1)development of the 3 D structural model of fault pattern;(2)estimation of the in-situ stress field;(3)calculation of the resolved-shear-to-normal-stress ratio(slip tendency)on each fault with varying geomechanical parameters(coefficient of friction,pore pressure and cohesion)as inputs;and(4)estimation of Coulomb static stress changes as a consequence of failure in a nearby fault.Through combination of all these analyses,we characterize in detail both the active deformation in the geothermal field and its relationship with hot fluid migration.

Tree community composition,structure and diversity along an elevational gradient in an Andean forest of Northern Ecuador

The Andean forests of northern Ecuador are known for their high levels of plant diversity relative to the area they occupy.Typically,these forests grow on steep slopes that lead to dramatic habitat gradients across short distances.These extreme habitat gradients make the Andean forest ecosystem an excellent natural laboratory for understanding the effect of elevation on forest community diversity,structure and composition.We established 31 plots(50 m×5 m)which are divided between two elevational transects in the cloud forest of the Siempre Verde Reserve in the western foothills of the Andes Mountains of northern Ecuador.All trees and tree ferns with a diameter at breast height(dbh)≥5 cm were measured and identified.We examined changes in community composition,structure,and diversity along and between the elevational transects and three elevational zones:low(2437–2700 m),middle(2756–3052 m),and high(3163–3334 m).We found four main trends associated with the elevational gradients at this site:(1)community composition differed between the two transects and among the three elevational zones according to N-MDS,ANOSIM,and percentage of shared species,with some species having limited distributions,(2)metrics of community structure showed opposite relationships with elevation,depending on the transect,with the only significant relationship(negative)found between basal area and elevation in the open trail transect,(3)alpha diversity,in general,peaked at mid-elevations,and(4)beta diversity consistently increased with distance between plots along elevation.The complexity of changes in community composition,structure,and alpha diversity along elevation may be related to the heterogeneity of the environment on a local scale,such as topography,soil composition,and even human impact,or to dispersal limitation and should be investigated further.These changes in community composition and the relatively high beta diversity found at this site exemplify the biological complexity of montane forest,reinforcing arguments from other studies on the importance of their conservation.