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There is a pressing need for global monitoring of snow water equivalent (SWE) at high spatiotemporal resolution, and L‐band (1–2 GHz) interferometric synthetic aperture radar (InSAR) holds promise. However, the technique has not seen extensive evaluation in forests. We evaluated this technique across varying forest canopy conditions using eight InSAR pairs collected at the Fraser Experimental Forest, Colorado, USA by NASA UAVSAR during the 10‐week NASA SnowEx 2021 Campaign. Compared with in situ measurements, we found root mean squared errors (RMSEs) of 14–17 mm for SWE changes in forest cover fractions (FCF) < 0.40, but RMSEs increased to 33–40 mm at FCF > 0.50. Statistical distributions between normalized lidar snow depths and normalized UAVSAR SWE were similar at FCF < 0.5, but diverged at FCF > 0.50. Thus, the upcoming NISAR L‐band satellite has strong potential for global snowpack monitoring, including below sparse to moderate forest cover. Plain Language Summary: Monitoring the amount of water stored in seasonal snowpacks is essential for water resource management, but it remains challenging, particularly in mountain and forest environments. Satellite radar techniques may provide a viable path forward for snowpack monitoring, particularly at longer radar wavelengths (>20 cm) such as the radar used for the upcoming NASA‐ISRO SAR satellite mission. At these longer wavelengths, the radar signal can penetrate forest canopy, but the canopy interferes with the signal and may reduce the accuracy of the radar snowpack measurement. We examined the influence of forest cover on airborne radar measurements of the snowpack in the Fraser Experimental Forest, Colorado, USA and observed errors that increased with greater forest cover. Notably, the radar measurements were accurate for sparse to moderately dense forest covers. The radar snowpack measurements reproduced elevational trends observed in lidar‐measured snow depths, but we identified snowpack measurement errors that correlated with oblique radar viewing geometries. Considering these limitations, we conclude that the NASA‐ISRO SAR satellite mission represents a promising path toward global snowpack monitoring. Key Points: We evaluated L‐band interferometry for snowpack monitoring in a montane forest in ColoradoRetrievals of changes in snow water equivalent from L‐band interferometry were accurate and unbiased in forest cover fractions <0.40Despite limitations, L‐band interferometry represents a promising path toward global snowpack monitoring [ABSTRACT FROM AUTHOR]

Elevation gradients provide excellent semi‐experimental conditions to investigate how the spatial distribution of biodiversity is shaped by the environment. Here, we investigate how temperature, productivity, and elevation are related to the diversity of anuran assemblages in a montane region of the southern Brazilian Atlantic Forest. We sampled 20 half‐hectare plots between 2020 and 2021, distributed along a sharp elevation gradient. Anuran species richness and abundance decreased with increasing elevation. We show a positive relationship between ambient temperature and frog species richness and abundance, highlighting the importance of temperature in shaping assemblages along the elevation gradient. In contrast, productivity did not affect species richness and abundance, suggesting that available energy via resources does not limit local frog diversity. We further observed marked differences in the composition of anuran assemblages between low and high elevation areas, which were related to temperature. Beta diversity is mainly driven by species replacements among assemblages, which were likely related to environmental conditions. These findings highlight the importance of incorporating protected areas that encompass the entire range of elevations to capture the full complement of landscape‐scale diversity. This is crucial as species showed limited distributions, and the marked effects of temperature should be explicitly considered under future scenarios of elevated upslope warming. [ABSTRACT FROM AUTHOR]

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Understanding the severity and extent of near surface critical zone (CZ) disturbances and their ecosystem response is a pressing concern in the face of increasing human and natural disturbances. Predicting disturbance severity and recovery in a changing climate requires comprehensive understanding of ecosystem feedbacks among vegetation and the surrounding environment, including climate, hydrology, geomorphology, and biogeochemistry. Field surveys and satellite remote sensing have limited ability to effectively capture the spatial and temporal variability of disturbance and CZ properties. Technological advances in remote sensing using new sensors and new platforms have improved observations of changes in vegetation canopy structure and productivity; however, integrating measures of forest disturbance from various sensing platforms is complex. By connecting the potential for remote sensing technologies to observe different CZ disturbance vectors, we show that lower severity disturbance and slower vegetation recovery are more difficult to quantify. Case studies in montane forests from the western United States highlight new opportunities, including evaluating post‐disturbance forest recovery at multiple scales, shedding light on understory vegetation regrowth, detecting specific physiological responses, and refining ecohydrological modeling. Learning from regional CZ disturbance case studies, we propose future directions to synthesize fragmented findings with (a) new data analysis using new or existing sensors, (b) data fusion across multiple sensors and platforms, (c) increasing the value of ground‐based observations, (d) disturbance modeling, and (e) synthesis to improve understanding of disturbance. Key Points: Increasing remote sensing capabilities improve observations of disturbance severity and recovery in varying critical zone settingsCase studies present how new approaches from multiple platforms and sensors better quantify post‐disturbance recovery of montane forestsWe suggest integrating the new approaches to refine remote sensing capabilities and resolve critical zone processes at multiple scales [ABSTRACT FROM AUTHOR]

Predicting how forest species composition may change in response to global change is essential for meaningful management. Which species are most likely to successfully recruit depends on a multitude of factors, but processes operating at the seed-toseedling transition being especially important. Here, we explore how insufficient seed dispersal (dispersal limitation) and ecological filtering of seedlings (establishment limitation) influence species recruitment in an Afromontane Forest. We combined census data from seeds in seed traps and seed-seedling transition plots in a Nigerian montane forest to measure dispersal and establishment limitation across species, life history strategies, and seed sizes. From 106 seed traps and 318 seedling plots, we recorded 11,278 seeds from 38 species and 2688 seedlings of 61 species. All species except for one liana showed strong dispersal limitation while 23 out of the 30 species showed establishment limitation. The two lianas sampled had significantly lower dispersal limitation compared to the trees investigated in the study. Our results suggest that both dispersal and establishment limitation are markedly high in this Afromontane forest than would be expected in a lowland counterpart. [ABSTRACT FROM AUTHOR]

The Kafa Biosphere Reserve (KBR) is the largest montane forest reserve in Ethiopia and was declared officially a United Nations Educational, Scientific and Cultural Organization (UNESCO) biosphere reserve in 2010. Only recently, however, has the reserve been surveyed in terms of its small‐ and medium‐sized mammal inhabitant species. The KBR supports a diverse variety of habitat types, which are increasingly under pressure from anthropogenic degradation. During the 2014 dry season and 2019 wet season, we used traps, mist‐nets, acoustic signals, photography and roadkill surveys to assess the small‐ and medium‐sized mammals of the reserve. We recorded 17 small‐ and five medium‐sized mammal species, almost half (45.5%) being endemic to Ethiopia. The grayish‐brown shaggy rat (Dasymys griseifrons) and two fruit bats (Epomophorus gambianus and Hypsignathus monstrosus) were recorded in the reserve for the first time. As a next step, a large‐scale, detailed inventory of the mammals in a wider area of southwestern Ethiopian forests and wetlands, including prevailing anthropogenic threats, is required. Notwithstanding, immediate conservation action by regional and national authorities to prevent further habitat loss to reduce the risk of local extinction is needed, particularly for endemic species or those exhibiting limited range distributions in southwestern Ethiopia. [ABSTRACT FROM AUTHOR]

Aim: Hispaniola is the second largest island in the Caribbean and a hot spot of biodiversity. The island was formed by the fusion of a northern and southern palaeo‐islands during the mid‐Miocene (15 Ma). The historical split of Hispaniola together with repeated marine incursions during the Pleistocene is known to have influenced lineage divergence and genetic structure in a few birds and mammals, but the effect on vascular plants is less understood. The conifer genus Podocarpus has two species, P.hispaniolensis and P.buchii, that are endemic to the mountains of Hispaniola and are IUCN endangered. The former occurs in the mountains of the north, and the latter in the south, with a region of sympatry in the Cordillera Central. Here, we evaluate the historical split of the two palaeo‐islands and repeated marine incursions as dispersal barriers to the geographical distribution of genetic diversity, genetic structure, divergence patterns and the historical demography of the two species. Location: Hispaniola island, Caribbean. Methods: Using genotyping‐by‐sequencing in 47 Podocarpus samples, we identified two sets of single nucleotide polymorphisms for our analyses (74,260 and 22,657 SNPs). We conducted a phylogenetic and an approximate Bayesian computation analysis to test evolutionary hypotheses of sympatric and allopatric speciation and stepping‐stone colonization. Results: Podocarpus showed a population genetic structure that corresponds to the geographic distribution of the species. Podocarpus on Hispaniola fit a stepping‐stone colonization model with bottlenecks at each mountain colonization event and speciation in Cordillera Central. Main conclusions: The historical events in question did not seem to have influenced the genetic structure, diversity or demography of Podocarpus; instead, the current geographic barriers imposed by lowland xeric valleys did. The clear divergence between species together with the elevated within‐population genetic diversity and significant genetic structure calls for a multi‐population in situ conservation of each species. [ABSTRACT FROM AUTHOR]

This study aims to identify the flower visitors of Mucuna thailandica (Fabaceae), endemic plant species in montane forests in Thailand, to determine their potential pollinators. The genus Mucuna produces papilionaceous flowers and has an explosive flower‐opening step. Explosive opening rapidly exposes stamens and pistil from keel petals and releases pollen. The flower of this species depends completely on animals to perform this step, essential for pollination success. Using a camera trap survey, we revealed that non‐flying mammals, such as squirrels (Callosciurus sp.) and masked palm civets (Paguma larvata), opened flowers explosively. Thus, these mammals contribute to the pollination of M. thailandica. This is the first report of non‐flying mammals contributing to pollination in montane forests in tropical Asia. [ABSTRACT FROM AUTHOR]

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The Eastern Arc Mountains are part of the Eastern Afromontane global biodiversity hotspot with a remarkable concentration of endemic species. Wildfire is among the major threats to biodiversity of forested mountains. This study assessed the effect of forest fire on the vegetation and understory birds in the Magamba montane forest, 5 years post a major fire outbreak. Mist‐net transects were used to sample understory birds. During the breeding season, active bird nests were searched using the time‐constrained method in both burnt and unburnt forests. Vegetation plots were sampled along the mist‐net transects, and shrubs and trees were identified and counted. The diversity of trees and shrubs, tree density per plot and canopy cover were significantly higher at unburnt than burnt sites with no difference in shrub density per plot. Bird species composition and number of nests between burnt and unburnt forests differed significantly with a considerable decline of forest interior bird specialists in burnt areas. An invasive plant species, Acacia melanoxylon, was found in dense groves within burnt sites and if not controlled, would escalate the fire regimes to further affecting plants and avian communities. Fire management, restoration and rehabilitation of burnt areas are among the immediate recommended actions. [ABSTRACT FROM AUTHOR]

Aim: We examined tree beta diversity in four biogeographical regions with contrasting environmental conditions, latitude, and diversity. We tested: (a) the influence of the species pool on beta diversity; (b) the relative contribution of niche-based and dispersal-based assembly to beta diversity; and (c) differences in the importance of these two assembly mechanisms in regions with differing productivity and species richness. Location: Lowland and montane tropical forests in the Madidi region (Bolivia), lowland temperate forests in the Ozarks (USA), and montane temperate forests in the Cantabrian Mountains (Spain). Methods: We surveyed woody plants with a diameter ≥2.5 cm following a standardized protocol in 236 0.1-ha forest plots in four different biogeographical regions. We estimated the species pool at each region and used it to recreate null communities determined entirely by the species pool. Observed patterns of beta diversity smaller or greater than the null-expected patterns of beta diversity implies the presence of local assembly mechanisms beyond the influence of the species pool. We used variation partitioning analyses to compare the contribution of niche-based and dispersal-based assembly to patterns of observed beta diversity and their deviations from null models among the four regions. Results: (a) Differences in species pools alone did not explain observed differences in beta diversity among biogeographic regions. (b) In 3/4 regions, the environment explained more of the variation in beta diversity than spatial variables. (c) Spatial variables explained more of the beta diversity in more diverse and more productive regions with more rare species (tropical and lower-elevation regions) compared to less diverse and less productive regions (temperate and higher-elevation regions). (d) Greater alpha or gamma diversity did not result in higher beta diversity or stronger correlations with the environment. Conclusion: Overall, the observed differences in beta diversity are better explained by differences in community assembly mechanism than by biogeographical processes that shaped the species pool. [ABSTRACT FROM AUTHOR]

Ecohydrological processes in tropical rainforests are insufficiently understood, and existing studies yield contradictory results. We investigated relative contributions of different soil depths to tree water uptake of 83 trees and possible species‐specific differences in a 50 × 50 m forest plot at four dates in a tropical montane forest in Kenya using stable water isotopes and the Bayesian mixing model framework MixSIAR. We found distinct individual tree differences (e.g. Drypetes gerrardii taking 75% of its water from <0.5 m, or a rather large shift in uptake patterns based on the climatic conditions, that is the fourth sampling date), but no consistent species‐specific or small‐scale spatiotemporal patterns in water uptake and depth contributions. Soil water δ18O showed a lateral variation of up to 6‰, which was accounted for by a spatial interpolation of soil water isotopes and enabled us to improve allocations of water uptake sources to individual trees. Our results show that ignoring the lateral variability of water isotope signatures in soils complicates the applicability of a mixing model in this context and might be a widespread constraint reducing the validity and comparability of mixing model results. Further research on underlying processes of water fluxes in forest ecosystems is urgently needed and we point out the need for considering large individual differences in water uptake patterns and small‐scale variability of soil water isotopic composition despite homogeneous soil characteristics. [ABSTRACT FROM AUTHOR]

Ecological restoration of riparian forest corridors at the landscape scale can facilitate recruitment of certain flora and fauna, thus possibly helping to maintain viable wildlife populations.We evaluated ecological restoration of three corridors between two protected Andean forests. Soil ants and eight environmental variables focused on edaphic conditions were monitored for 8 years following restoration activity. Soil ants were collected in pitfall traps and by leaf litter extraction on 21 plots classified into five types of habitat: large forest patches, riparian forests, two types of restoration corridors on former timber and pasture land (R‐Forestry and R‐Pasture, respectively), and Pasture.A total of 132 ant species belonging to 40 genera were found. Among these, 112 species were found in Forests, 105 in Riparian, 80 in R‐Forestry, 79 in R‐Pasture and 63 in Pasture. Composition analyses (canonical correspondence analysis and NMDS) showed that the ant community in restoration corridors and pastures is far from resembling that of the forests. Yet, there is biological progress with respect to the Pasture.Gnamptogenys bisulca and Pheidole pygmaea were indicator species for advanced restoration progress because of their close association to forests, while Linepithema piliferum indicated a reversal of restoration progress due to its preference for open habitats.Since both ant richness and composition in restored areas do not yet resemble the reference forest ecosystem, we suggest that other interventions such as restoring wider corridors and changing to wild‐friendly agriculture around the reserves might improve restoration efforts in Andean landscapes. [ABSTRACT FROM AUTHOR]

Most primates experience seasonal fluctuations in the availability of food resources and face the challenge of balancing energy expenditure with energy gain during periods of resource scarcity. This is likely to be particularly challenging in rugged, montane environments, where available energy is relatively low and travel costs are high. Chimpanzees (Pan troglodytes) show extensive behavioral diversity across study sites. Yet, as most research has focused on low‐ and mid‐elevation sites, little is known on how chimpanzees respond to periods of low fruit availability in harsh montane environments. We use focal follow and phenology data to investigate how fruit availability influences daily path length and monthly home range in chimpanzees living in Nyungwe National Park, a montane forest in Rwanda. Nyungwe chimpanzees decreased their daily travel distances during periods of fruit scarcity. However, this decrease in travel effort did not correspond with a decrease in foraging area. Instead, monthly homes ranges shifted location across the study period. Nyungwe chimpanzees occupy a relatively wide altitudinal range and the shifts in monthly home range location may reflect differences in the altitudinal distribution of food resources. Chimpanzee monthly diet was often dominated by one or two species and each of these species were confined to different elevation zones. One important species, Podocarpus latifolius, grew only at high elevations (2,600–2,950 m) and chimpanzees ranged at the altitudinal peak of their range for 2 consecutive months while feeding on this species. Thus, while high elevations are often thought to be harsh environments for primates, they can be an important part of a species' home range when they provide a refugium for densely distributed, important food species. Highlights: Chimpanzees in a montane forest decreased their daily path length and shifted their home range during periods of fruit scarcity.High elevations provide a habitat for densely distributed, important food species and are a valuable part of their home range. [ABSTRACT FROM AUTHOR]

Aims: Climate shapes forest types on our planet and also drives the differentiation of zonal vegetation at regional scale. A climate‐based ecological model may provide an effective alternative to the traditional approach for assessing limitations, thresholds, and the potential distribution of forests. The main objective of this study is to develop such a model, with a machine‐learning approach based on scale‐free climate variable estimates and classified vegetation plots, to generate a fine‐scale predicted vegetation map of Taiwan, a subtropical mountainous island. Location: Taiwan. Methods: A total of 3,824 plots from 13 climate‐related forest types and 57 climatic variable estimates for each plot were used to build an individual ecological niche model for each forest type with random forest (RF). A predicted vegetation map was developed through the assemblage of RF predictions for each forest type at the spatial resolution of 100 m. The accuracy of the ensemble RF model was evaluated by comparing the predicted forest type with its original classification by plot. Results: The climate environment of regions higher than 100 m above sea level in Taiwan was classified into potential habitats of 13 forest types by using model predictions. The predicted vegetation map displays a distinct altitudinal zonation from subalpine to montane cloud forests, followed by the latitudinal differentiation of subtropical mountain forests in the north and tropical montane forests in the south, with an average mismatch rate of 6.59%. An elevational profile and 3D visualization demonstrate the excellence of the model in estimating a fine, precise, and topographically corresponding potential distribution of forests. Conclusions: The machine‐learning approach is effective for handling a large number of variables and to provide accurate predictions. This study provides a statistical procedure integrating two sources of training data: (a) the locations of field sampling plots; and (b) their corresponding climate variable estimates, to predict the potential distribution of climate‐related forests. [ABSTRACT FROM AUTHOR]

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Copyright of Biotropica is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Anthropogenic nitrogen (N) deposition can most likely increase temperate forest soil organic carbon (SOC) storage. Increased SOC is usually suggested to be associated with the suppression of SOC decomposition, which has been hypothesized to be due to the decrease in the activity of lignin‐degrading extracellular enzymes and/or the decrease in soil acidity under N addition. However, the potential mechanism of SOC protection derived from N addition is less understood. Here in a low‐deposition temperate montane forest, short‐term N addition could increase SOC storage in the aggregate fraction but not in the bulk soil. N‐induced SOC accumulation was partly associated with the suppressed SOC decomposition (indicated by lower soil respiration) that resulted from the reduced microbial biomass rather than from decreased lignin‐degrading enzyme activity or from reduced soil acidity. In addition, N addition promoted soil aggregate formation, which could partly suppress SOC decomposition by protecting new carbon that originated from plant litter residue to a greater degree, while dissolved organic carbon retention in the mineral soils played a limited role in the SOC sequestration derived from N addition, at least in the short term. A conceptual model was proposed and highlighted a new underlying mechanism of new carbon protection by enhanced aggregate formation, other than the role of microbial suppression, to explain the positive effect of anthropogenic N deposition on forest SOC. Plain Language Summary: Since the industrial revolution, atmospheric active nitrogen (N) deposition has continued to increase worldwide due to human activities. N is considered as an essential element for ecosystem, and anthropogenic N deposition has been found to influence many aspects of forest ecosystems, such as soil acidity, the fate, cycle, and storage of soil carbon (C). It is very important to understand the changes in forest soil C and the potential mechanisms as forest soil holds a large C storage and plays a significant role in global C cycle and global warming. However, the direct, extent, and mechanism of the effects of N deposition on forest carbon are still unclear. Based on an experimental N‐addition treatment conducted in a montane forest, we found that short‐term N addition could increase soil storage in the aggregate fraction but not in the bulk soil. The N‐induced aggregate C accumulation is associated with the enhanced soil aggregate formation inducing by N addition. Greater aggregate formation could protect greater C in the aggregate from microbial decomposition. This result presents a new conceptual framework regarding interactions between C and N cycling and provides a new insight in the effect of N deposition on soil structure and dynamic of carbon. Key Points: Short‐term N addition increases soil C in aggregate fraction not yet in bulk soilN‐induced enhanced aggregate formation protects more new C from decompositionN‐derived suppressed C decomposition is related to lower microbial biomass [ABSTRACT FROM AUTHOR]

Land use change modifies the environment at multiple spatial scales, and is a main driver of species declines and deterioration of ecosystem services. However, most of the research on the effects of land use change has focused on taxonomic diversity, while functional diversity, an important predictor of ecosystem services, is often neglected. We explored how local and landscape scale characteristics influence functional and taxonomic diversity of hummingbirds in the Andes Mountains in southern Ecuador. Data was collected in six landscapes along a land use gradient, from an almost intact landscape to one dominated by cattle pastures. We used point counts to sample hummingbirds from 2011 to 2012 to assessed how local factors (i.e., vegetation structure, flowering plants richness, nectar availability) and landscape factors (i.e., landscape heterogeneity, native vegetation cover) influenced taxonomic and functional diversity. Then, we analyzed environment - trait relationships (RLQ test) to explore how different hummingbird functional traits influenced species responses to these factors. Taxonomic and functional diversity of hummingbirds were positively associated with landscape heterogeneity but only functional diversity was positively related to native vegetation coverage. We found a weak response of taxonomic and functional diversity to land use change at the local scale. Environment-trait associations showed that body mass of hummingbirds likely influenced species sensitivity to land use change. In conclusion, landscape heterogeneity created by land use change can positively influence hummingbird taxonomic and functional diversity; however, a reduction of native vegetation cover could decrease functional diversity. Given that functional diversity can mediate ecosystem services, the conservation of native vegetation cover could play a key role in the maintenance of hummingbird pollination services in the tropical Andes. Moreover, there are particular functional traits, such as body mass, that increase a species sensitivity to land use change. [ABSTRACT FROM AUTHOR]

In habitats such as temperate evergreen forests, fruit, and seed productivity is reported to exhibit marked changes in seasonal availability, such that fruit is most available in summer and seeds are most available in autumn. Primates living in these habitats, therefore, are expected to adjust their diets in response to the spatial and temporal variation in these food resources. We studied the diet and feeding behavior of a group of 42 Phayre's langurs ( Trachypithecus phayrei) living in a northern (24°48′N) montane habitat (1,700-2,350 m) in Mt. Gaoligong, Yunnan, China from August 2012 to July 2013. The langurs were found to forage on 50 plant species, of which 28 species each accounted for more than 1% of their annual feeding time. Castanopsis echidnocarpa, the most abundant species in their habitat, accounted for 17.5% of the total forest trees, and contributed to the largest proportion of the annual langur diet. The primary component of the langur diet was composed of fruits (22.2%), seeds (18.7%), and buds and young leaves (41.5%). Mature leaves accounted for only 4.1% of their diet. Based on DBH and the percent of the crown containing edible food items, we found that the langurs changed their monthly diet according to the availability of fruits and seeds (Spearman rank correlation: r = 0.609, p = 0.035), and buds and young leaves (Spearman rank correlation: r = 0.837, p = 0.001). The seeds of C. echidnocarpa accounted for 12.5% of langur feeding time. A single tree produced a large seed and fruit crop, which likely reduced opportunities for within-group feeding competition. We argue that the resource productivity of this northern montane enables Phayre's langurs to live in stable groups that are 3.6 times larger than reported for Phayre's langurs living in other habitats. [ABSTRACT FROM AUTHOR]

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Predicting restoration outcomes requires an understanding of the natural variability of ecosystem properties. A hierarchy of predictability has been proposed that ranks measures of restoration success from most-to-least predictable in the following order: vegetation structure > taxonomic diversity > functional diversity > taxonomic composition. This hierarchy has not been tested empirically, and the location within the hierarchy of trait-based measures, such as community-level trait means and variances, is not well understood., Our objective was to test the hierarchy of predictability in one of the longest running ecological restoration experiments in the western USA. We used linear mixed effects models to analyse changes in herbaceous biomass, species richness, two functional diversity (FD) indices, community-weighted mean (CWM) traits and taxonomic composition among experimental restoration treatments from 1992 to 2014 in a ponderosa pine-bunchgrass ecosystem. Restoration treatments included combinations of light or heavy tree thinning and no fire or repeated prescribed fire every 4 years to release the herbaceous understorey from overstorey competition., Herbaceous biomass and species richness were the two most predictable and least variable measures of success, whereas taxonomic composition exhibited the highest variability among plots through time. Trait-based measures of FD tended to be more predictable and less variable than CWM trait values in this experiment. Both CWM trait values and FD were less variable among plots than taxonomic composition., Synthesis and applications. Ecosystem properties that are intrinsically more variable over space and time will often be the least predictable restoration outcomes. Restoration practitioners can expect vegetation structure, species richness and functional diversity to be more predictable and less variable than taxonomic composition, which can exhibit dynamic responses to restoration treatments over time. Monitoring dominant native and invasive species will always be important, but given the functional redundancy that can occur within communities, strict targets based on composition may rarely be met. Trait-based metrics that integrate taxonomic composition into their calculation are less variable and potentially more meaningful for evaluating ecosystem responses. The hierarchy of predictability should be tested in a range of ecosystems to determine its generality. [ABSTRACT FROM AUTHOR]

Questions (1) How do seed density and species richness of late-successional, pioneer and non-forest species change from forest interior to deforested habitats? (2) Are seed density and species richness of seed species dispersed into deforested areas enhanced by perch structures? (3) Do morphological seed traits of forest and non-forest plant species change from the forest interior to deforested areas? Location Deforested tropical mountains of Chulumani, La Paz, Bolivia. Methods At eight study sites, we installed a system of 38 seed traps along a transect of 240 m from the forest interior (160 m from the forest margin) toward deforested areas (80 m from the forest margin). Half of the seed traps installed in the deforested areas were positioned under perch structures. We identified captured seeds to morpho-species or species level and recorded morphological seed traits (i.e. seed mass, seed length, seed width) and species origin (i.e. late-successional, pioneer, non-forest species). Results Seed density and species richness of late-successional and pioneer species declined from the forest interior toward deforested areas. Seed limitation was particularly strong for large-seeded species. Perches in deforested areas strongly increased the density and to some extent as well as the species richness of seeds dispersed into these areas, but did not alter the composition of seed traits and species origin in comparison to seed traps without perches. Conclusions We found a strong seed dispersal limitation in deforested areas, which was mitigated by the presence of perch structures, at least in terms of seed density and species richness. However, the dispersal limitation of late-successional plant species with large seeds was not compensated by the presence of perching structures. Nevertheless, the establishment of artificial perch structures is likely to be a promising strategy for capturing seeds in deforested areas that may establish under bracken fronds in the long term. [ABSTRACT FROM AUTHOR]

Rising temperatures, a widespread consequence of climate change, have been implicated in enigmatic amphibian declines from habitats with little apparent human impact. The pathogenic fungus Batrachochytrium dendrobatidis (Bd), now widespread in Neotropical mountains, may act in synergy with climate change causing collapse in thermally stressed hosts. We measured the thermal tolerance of frogs along a wide elevational gradient in the Tropical Andes, where frog populations have collapsed. We used the difference between critical thermal maximum and the temperature a frog experiences in nature as a measure of tolerance to high temperatures. Temperature tolerance increased as elevation increased, suggesting that frogs at higher elevations may be less sensitive to rising temperatures. We tested the alternative pathogen optimal growth hypothesis that prevalence of the pathogen should decrease as temperatures fall outside the optimal range of pathogen growth. Our infection-prevalence data supported the pathogen optimal growth hypothesis because we found that prevalence of Bd increased when host temperatures matched its optimal growth range. These findings suggest that rising temperatures may not be the driver of amphibian declines in the eastern slopes of the Andes. Zoonotic outbreaks of Bd are the most parsimonious hypothesis to explain the collapse of montane amphibian faunas; but our results also reveal that lowland tropical amphibians, despite being shielded from Bd by higher temperatures, are vulnerable to climate-warming stress. Fisiología Termal, Enfermedades y Disminuciones de Anfibios en las Laderas Orientales de los Andes [ABSTRACT FROM AUTHOR]

Aim We identify the main forest vegetation types in Taiwan, provide their formal definitions and describe their species composition, habitat affinities and distribution. Location Taiwan. Methods A data set of 9822 vegetation plots with environmental characteristics recorded in the field or derived from digital maps in GIS was compiled from historical literature and an extensive field survey. Using expert knowledge, 6574 of these plots were used to build a classification into broad vegetation types. The units of the resulting classification were formally defined using a Cocktail determination key, which can be used for the automatic assignment of new vegetation plots to these vegetation types. Results Twelve vegetation types of zonal forests and nine types of azonal forests were distinguished. Zonal types in the subtropical region, from high mountains to foothills, are Juniperus subalpine coniferous woodland, Abies- Tsuga upper-montane coniferous forest, Chamaecyparis montane mixed cloud forest, Fagus montane deciduous broad-leaved cloud forest, Quercus montane evergreen broad-leaved cloud forest, Machilus- Castanopsis sub-montane evergreen broad-leaved forest, Phoebe- Machilus sub-montane evergreen broad-leaved forest and Ficus- Machilus semi-evergreen foothill forest. Zonal types in the tropical region, from high mountains to foothills, are Pasania- Elaeocarpus montane evergreen broad-leaved cloud forest, Drypetes- Helicia sub-montane evergreen broad-leaved forest, Dysoxylum- Machilus foothill evergreen broad-leaved forest and Aglaia- Ficus foothill evergreen broad-leaved forest. Azonal types are Illicium- Cyclobalanopsis tropical winter monsoon forest, Pyrenaria- Machilus subtropical winter monsoon forest, Diospyros- Champereia tropical rock-outcrop forest, Zelkova- Quercus subtropical rock-outcrop forest, Pinus successional woodland, Alnus successional woodland, Trema- Mallotus successional woodland, Scaevola- Hibiscus seashore woodland and Kandelia mangrove. Conclusions The diversity of forest vegetation in Taiwan is strongly structured by the temperature and moisture gradient. Along the temperature gradient, five altitudinal zones can be recognized. Azonal forest types develop at sites affected by the winter monsoon, on steep slopes, rocky soils, in seashore saline habitats and in places disturbed by fire, landslides and human activities. Zonal vegetation contains a higher ratio of endemic and Pacific species and occurs in wetter habitats, whereas azonal vegetation contains co-existing species from different regions and usually occurs in drier habitats. [ABSTRACT FROM AUTHOR]

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Aim Understanding patterns of species turnover along environmental gradients and their consistency across taxonomic groups is central to the study of biodiversity. We may expect congruence in diversity patterns across groups whose ranges could be influenced by species interactions. We explore associations between bird and vegetation communities in the tropical Andes to determine whether patterns of species richness and turnover in birds and trees are congruent with elevation, and whether tree species composition, vegetation structure, elevation, or a combination of these best predicts bird species composition. Location A forested 2600-m elevational gradient on the eastern slope of the Peruvian Andes. Methods Bird surveys and vegetation measurements were conducted at 172 points, and a subset of these were spatially matched with fourteen 1-ha tree inventory plots. Diversity patterns were described for trees, birds, and avian foraging guilds. We used dissimilarity matrices to examine patterns of turnover and nestedness. Turnover of birds and trees was examined by comparing compositional change of adjacent plots along the gradient. Multiple regression on distance matrices was employed to determine contributions of tree species composition, vegetation structure and elevation to explaining variation in bird species composition. Results Species richness was higher for trees than for birds, and whereas diversity in both taxa decreased with elevation, tree richness showed a low-elevation plateau before declining at higher elevations. Tree species had narrower distributions compared to birds, but patterns of turnover were largely congruent between taxa. Nestedness contributed much less to dissimilarity than turnover, although birds showed higher nestedness, particularly at high elevations. Tree species composition, elevation and vegetation structure were all important predictors of bird species composition; the best model explained 78% of bird dissimilarity across plots. Tree species composition was always included in the best models, for all birds and foraging guilds. Main conclusions Our assessment of Andean bird and vegetation communities suggests strong correspondence, perhaps due to direct interactions or similar underlying drivers. We hypothesize that with climate change, range shifts in these groups may not occur independently. Rather, birds may have delayed upslope shifts or may be limited to high-elevation patches where appropriate vegetation communities exist. [ABSTRACT FROM AUTHOR]

This study examines how fragmentation through changes in patch size and increasing distances between forest patches affects bird species richness. Numbers of bird species were higher in large forest patches and decrease with decreasing patch size. Bird species richness also decreased with increased isolation of forest patches. Suitable trees should be planted in the gaps between the forests that will create wildlife corridors to maintain connectivity. [ABSTRACT FROM AUTHOR]

Aim Our aims were to provide a detailed chronology of past vegetation changes in the tropical mountains of west-central Africa since the Last Glacial Maximum and to discuss montane forest responses to climate change in terms of distribution and biodiversity. Location Lake Bambili, western Cameroon (05°56′ N, 10°14′ E, 2273 m a.s.l.). Methods Fossil pollen was extracted from a long, continuous and well-dated sedimentary sequence extending back 20,000 years. Pollen diversity and evenness estimates were based on rarefaction analysis and on Simpson's (1/ D) index. Results Forest was nearly absent from high elevations during the last glacial period. It expanded gradually from 18.4 cal. kyr bp, interrupted only by reversals coincident with the Heinrich 1 (H1) and Younger Dryas ( YD) climatic events, and then suddenly collapsed at 3.3 cal. kyr bp. This switch from forest to grassland communities occurred within a time span of three centuries. After 3.3 cal. kyr bp only short and taxon-poor forest phases are recorded, specifically between 2.7 and 1 cal. kyr bp and in recent centuries. Main conclusions Our data indicate that the mountain forests of Cameroon are recent, resulting from plant migrations from various sources from 18.4 cal. kyr bp onwards. Their progressive development closely followed intensification of the Atlantic monsoon, leading to the formation of a dense forest between 11.7 and 3.3 cal. kyr bp. The composition of this forest included the co-occurrence of species whose ranges do not overlap today, and indicates the potential for the development of unique iterations of climax forests through time. These forests appear to be very sensitive to Northern Hemisphere climate change, with phases of expansion/contraction coeval with the boreal deglacial signal, including widely recognized events such as H1, the YD and the 8.2 ka event. From 8.2 cal. kyr bp onwards, the progressive opening of the canopy is likely to reflect increased seasonality in rainfall related to more frequent El Niño/Southern Oscillation ( ENSO) events. The final step of this history was the collapse of the montane forest at 3.3 cal. kyr bp. During the last millennium, very severe disruptions have meant that only the most rapidly dispersing species could spread, contributing to a drastic loss of forest biodiversity that has been accentuated by human impact in the last few centuries. [ABSTRACT FROM AUTHOR]

ABSTRACT In humid, forested mountain belts, bedrock landslides can harvest organic carbon from above ground biomass and soil (OCmodern) while acting to refresh the landscape surface and turnover forest ecosystems. Here the impact of landslides on organic carbon cycling in 13 river catchments spanning the length of the western Southern Alps, New Zealand is assessed over four decades. Spatial and temporal landslide maps are combined with the observed distribution and measured variability of hillslope OCmodern stocks. On average, it is estimated that landslides mobilized 7.6 ± 2.9 tC km−2 yr−1 of OCmodern, ~30% of which was delivered to river channels. Comparison with published estimates of OCmodern export in river suspended load suggests additional erosion of OCmodern by small, shallow landslides or overland flow in catchments. The exported OCmodern may contribute to geological carbon sequestration if buried in sedimentary deposits. Landslides may have also contributed to carbon sequestration over shorter timescales (<100 years). 5.4 ± 3.0 tC km−2 yr−1 of the eroded OCmodern was retained on hillslopes, representing a net-carbon sink following re-vegetation of scar surfaces. In addition, it was found that landslides caused rapid turnover of the landscape, with rates of 0.3% of the surface area per decade. High rates of net ecosystem productivity were measured in this forest of 94 ± 11 tC km−2 yr−1, which is consistent with rapid landscape turnover suppressing ecosystem retrogression. Landslide-OCmodern yields and rates of turnover vary between river catchments and appear to be controlled by gradients in climate (precipitation) and geomorphology (rock exhumation rate, topographic slope). Copyright © 2011 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Amphibians are declining worldwide, but these declines have been particularly dramatic in tropical mountains, where high endemism and vulnerability to an introduced fungal pathogen, Batrachochytrium dendrobatidis (Bd), is associated with amphibian extinctions. We surveyed frogs in the Peruvian Andes in montane forests along a steep elevational gradient (1200-3700 m). We used visual encounter surveys to sample stream-dwelling and arboreal species and leaf-litter plots to sample terrestrial-breeding species. We compared species richness and abundance among the wet seasons of 1999, 2008, and 2009. Despite similar sampling effort among years, the number of species (46 in 1999) declined by 47% between 1999 and 2008 and by 38% between 1999 and 2009. When we combined the number of species we found in 2008 and 2009, the decline from 1999 was 36%. Declines of stream-dwelling and arboreal species (a reduction in species richness of 55%) were much greater than declines of terrestrial-breeding species (reduction of 20% in 2008 and 24% in 2009). Similarly, abundances of stream-dwelling and arboreal frogs were lower in the combined 2008-2009 period than in 1999, whereas densities of frogs in leaf-litter plots did not differ among survey years. These declines may be associated with the infection of frogs with Bd. B. dendrobatidis prevalence correlated significantly with the proportion of species that were absent from the 2008 and 2009 surveys along the elevational gradient. Our results suggest Bd may have arrived at the site between 1999 and 2007, which is consistent with the hypothesis that this pathogen is spreading in epidemic waves along the Andean cordilleras. Our results also indicate a rapid decline of frog species richness and abundance in our study area, a national park that contains many endemic amphibian species and is high in amphibian species richness. [ABSTRACT FROM AUTHOR]

This chapter analyses the climatic conditions prevailing at sites where tropical montane cloud forests (TMCF) have been reported. Spatial data-sets of climate were used to describe the climate at 477 cloud forest sites identified by United Nations Environment Program (UNEP)-WCMC. Some 85% of the sites are found at altitudes between 400 and 2800 m a.s.l., with an average altitude of 1700 m. The range of altitudes at which cloud forests are found is extensive (220-5005 m). The climate of cloud forests is highly variable from site to site, with an average rainfall of ∼2000 mm year and an average temperature of 17·7 °C. In addition, cloud forests are found in seasonal and aseasonal environments alike, both in terms of rainfall and temperature. There are some clear differences in the climates of cloud forests found in Africa, Latin America and the Caribbean, and those in Asia. Cloud forests are found to be wetter (with incident rainfall being 184 mm year higher on average), cooler (by 4·2 °C on average), and less seasonally variable than other montane forests not affected significantly by fog and low cloud. Cloud forests are also almost completely confined to a zone within 350 km from the nearest coast. Finally, the climatic representativity of 14 intensively studied cloud forest sites (ISS) was analysed, as a group, the sites provided a fair representation of the climates found in cloud forests, evenly covering the ranges in temperature and rainfall. The majority of cloud forest sites occur in regions with 2000-2600 mm of rainfall and annual mean temperatures ( T) of 14-18 °C. Relatively dry cloud forest sites (<1000 mm of rain year) are under-represented in the UNEP-WCMC data-base. Copyright © 2010 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

This study used hourly data of rainfall, water captured by a sheltered fog gauge and wind speed as collected at a montane forest site in northern Thailand during nearly 3 years to test the efficiency of the rain-protected passive fog gauge as a predictor of fog occurrence. To separate possible contributions by wind-driven rain (WDR) from fog, the maximum rate of water input to the fog gauge during rainless periods (Fog) was derived as a function of wind speed. During periods with rain and fog, the fog gauge often produced values above the Fog line, suggesting contributions by WDR. The specific conditions of rainfall intensity and wind speed under which this happened were identified and the corresponding data were excluded from the fog data-set for subsequent reanalysis. Based on the recalculated data-set, inter-annual and seasonal variations as well as the diurnal pattern of fog occurrence at the studied forest are described. Fog-induced canopy drip during rainless periods was only 19·3 mm over the 3 years, being less than 0·5% of total throughfall and ∼33% of the corresponding catch by the fog gauge (58 mm). However, the fog gauge captured nearly 18 times more water (1033 mm) during all times when WDR could reasonably be excluded. Copyright © 2010 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Questions: How do gap aspect, openness, age and gap density in the surroundings affect diversity and composition of lianas within treefall gaps? Are the variation patterns in liana communities within treefall gaps associated with their climbing mechanisms? Location: Subtropical montane forests in northwestern Argentina. Methods: We used ordination analyses (NMDS) and multiple regressions to describe liana communities (species and climbing groups, stems ≥ 1 cm) in 35 gaps located in a 6-ha plot and to assess relationships with aspect, canopy and subcanopy openness, age and density of recant (three to eight years old) and old (> 8 years old) gaps. Results: Treefall gaps segregated in the ordination diagrams bused on their liana species and climbing mechanisms composition: gaps surrounded by a higher density of recent gaps showed higher densities of lianas species using tendrils, spines / hooks and voluble stems. Liana density and richness (independent of stem density) were also positively associated with the density of recent gaps in the surroundings, and negatively associated to gap age. The number of liana species corrected per area was negatively associated to gap aspect and subcanopy openness, and absolute number of liana species was positively associated to gap canopy openness. Conclusions: This study integrates the analysis of different factors influencing liana communities within treefall gaps, and shows that spatial context of gap density (a variable largely neglected in previous studies) is particularly important on lianas composition and diversity, probably by increasing propagule input and the availability of small trellises for support. [ABSTRACT FROM AUTHOR]

Montane evergreen forest in SE Asia is structurally and floristically different from lowland habitats. The response of large mammals to this variation is largely unexplored. We used sign transects to compare community structure of large mammals in montane (>1100 m), and lowland (<1100 m) forest types over 4 yr in western Thailand. Relative abundance of most ungulate species was significantly higher in lowland forest, except for elephant ( Elephas maximus) and tapir ( Tapirus indicus), which were most abundant in montane forest (based on chi-square tests of sign encounter rates). Sexual segregation was apparent for gaur ( Bos gaurus): breeding herds were concentrated in the lowlands, whereas single males were most abundant in montane forest. Large cat abundance was similar in both elevation zones. Tapir, single gaur, and bears ( Ursus spp.) characterized the montane mammal community, whereas most other ungulate species and social groups were indicative of lowland forest (based on discriminant function analysis). Results pertain only to the dry season; seasonal movements could alter the patterns we observed. Differences in community structure between elevation zones are hypothesized to result from differences in habitat structure, resource availability, and human impacts. Lowland forests provide bamboo, grass, and mineral licks, probably accounting for higher ungulate densities despite higher levels of hunting. These resources are scarce in montane forest. However, montane forest functions as a refuge for at least three globally threatened large mammal species, because commercial hunting is concentrated in the more accessible lowlands. [ABSTRACT FROM AUTHOR]

Unlike the seriate lowland rain forests in SE Asia, the tropical vegetation of Xishuangbanna (SW China) has developed in habitats with comparatively lower temperatures and precipitation. Consequently, although most of the families and genera of the flora are components of tropical ecosystems, many have reached their distribution limits in latitude. Selection pressures on sexual systems in these environments may be different from that experienced in lowland tropical regions. Here, we examine the sexual systems of 685 species of flowering plants belonging to 109 families and 356 genera based on 42 plots with a total area of 15.4 ha and compare our results with surveys of sexual systems from other tropical ecosystems. Among these species, 60.6 percent were hermaphroditic, 14.3 percent were monoecious, and 25.1 percent were dioecious. The percentage of dioecious sexual system among tree species (26.1%) was similar or higher than that of other tropical tree floras. Monoecy was significantly associated with the tree growth form and was relatively common in seasonal forest vegetation. Sexual systems involving unisexual flowers (dicliny) are particularly well represented in the tropical forests of Xishuangbanna accounting for 39.4 percent of all species surveyed. This pattern may be associated with the prevalence of relatively small inconspicuous flowers in the tropical forests of SE Asia and their correlation with diclinous sexual systems generally. [ABSTRACT FROM AUTHOR]

Although swarm-raiding army ants are considered keystone predators in tropical forest ecosystems, information on the prey spectra of most species is based on anecdotal reports and not on systematic studies with extensive sampling. We analysed prey samples of 18 colonies of the two afrotropical species Dorylus ( Anomma) molestus and Dorylus ( Anomma) wilverthi (4289 prey items in total) to examine the prey composition variation within and between species and to determine the best methodology to obtain reliable prey spectrum estimates for a given species, site and season. Variation in prey composition was substantial for D. molestus even within a single site and season, with the biomass proportion of the most important prey type differing by a factor of 12. Conclusions from studies using small samples sizes may thus be misleading. We demonstrate that the method of assessing prey spectra in terms of relative prey item numbers often produces biased results, and therefore recommend relative prey biomass as the more useful parameter. The near absence of earthworms, which always constituted a substantial part of the D. molestus prey, in the diet of D. wilverthi is interpreted to result from subtle differences in swarm-raiding behaviour between these two species, but could alternatively also be due to low availability. Similar studies recording prey composition as biomass proportions and analysing large samples sizes from many colonies are needed to understand the effect of army ant swarm raids on invertebrate communities in afrotropical forests. [ABSTRACT FROM AUTHOR]

Aim To show that the frequently reported positive trend in the abundance–range-size relationship does not hold true within a montane bird community of Afrotropical highlands; to test possible explanations of the extraordinary shape of this relationship; and to discuss the influence of island effects on patterns of bird abundance in the Cameroon Mountains. Location Bamenda Highlands, Cameroon, Western Africa. Methods We censused birds during the breeding season in November and December 2003 using a point-count method and mapped habitat structure at these census points. Local habitat requirements of each species detected by point counts were quantified using canonical correspondence analysis, and the size of geographical ranges of species was measured from their distribution maps for sub-Saharan Africa. We tested differences in abundance, niche breadth and niche position between three species groups: endemic bird species of the Cameroon Mountains, non-endemic Afromontane species, and widespread species. Results We detected neither a positive nor negative abundance–range-size relationship in the bird community studied. This pattern was caused by the similar abundance of widespread, endemic and non-endemic montane bird species. Moreover, endemic and non-endemic montane species had broader local niches than widespread species. The widespread species also used more atypical habitats, as indicated by the slightly larger values of their niche positions. Main conclusions The relationship detected between abundance and range size does not correspond with that inferred from contemporary macroecological theory. We suggest that island effects are responsible for the observed pattern. Relatively high abundances of montane species are probably caused by their adaptation to local environmental conditions, which was enabled by climatic stability and the isolation of montane forest in the Cameroon Mountains. Such a unique environment provides a less suitable habitat for widespread species. Montane species, which are abundant at present, may also have had large ranges in glacial periods, but their post-glacial distribution may have become restricted after the retreat of the montane forest. On the basis of comparison of our results with studies describing the abundance structure of bird communities in other montane areas in the Afrotropics, we suggest that the detected patterns may be universal throughout Afromontane forests. [ABSTRACT FROM AUTHOR]

Aim For epiphytic plants trees are habitat units, and tree size determines epiphyte species richness. While growing, trees generate vertical microhabitats that are exploited by epiphytes. One would expect to find four different types of relationship between tree size and epiphyte species richness: positive linear (young trees), neutral (old trees), negative (old decaying trees) and positive asymptotic (trees of mixed size class in a mature forest). We tested these relationships in plots of colonizing sweetgum trees in pastureland, isolated remnant trees in pastureland (old oaks) and sweetgum and oaks in a pristine forest. Location The study was carried out in a landscape shaped by the fragmentation of lower montane cloud forest in San Andrés Tlalnelhuayocan (19°30′56′′ N and 96°59′50′′ W; 1500–1600 m a.s.l.) in central Veracruz, Mexico. Methods We measured the d.b.h. of all oaks and sweetgum trees (d.b.h. ≥ 5 cm) present in pastureland and in three 100 m2 plots of a lower montane cloud forest. All trees were climbed and species richness of the epiphytes recorded. Results As expected, colonizer trees in pastureland showed a linear positive relationship. Although we found evidence that remnant oaks in pastureland had a neutral relationship between tree size and epiphyte species richness, the low power of the test did not allow us to make conclusions about the kind of relationship. Mixed size-class pristine forest trees showed a positive linear relationship between tree size and epiphyte species richness instead of a positive asymptotic one. Main conclusions Our results suggest that in the study area epiphyte communities are unsaturated, as the number of species increases with tree size and does not reach a ceiling. This evidence supports the idea that the species–area relationship is not asymptotic. However, the epiphyte community on remnant pastureland oaks may be saturated as epiphyte species richness did not increase with tree size, but a larger sample size is needed to confirm the neutral pattern. Neutral, asymptotic and negative patterns in the relationship between tree size and epiphyte species richness depend on the saturation of the trees by epiphytes. Other studies have suggested tree saturation, but further research is necessary in order to confirm or rule out these patterns. [ABSTRACT FROM AUTHOR]

This study investigates diversity patterns of vascular plants and plant-feeding geometrid moths during montane rain forest regeneration in relation to the biogeographical and historical conditions of Mt Kilimanjaro. Investigations were undertaken on the south-western slopes of Mt Kilimanjaro at altitudes between 2075 and 2265 m. Thirteen plots were selected for this study. Four of these were situated in the middle of large clearings (> 1000 m2), three in secondary forest, two in mature forest remnants surrounded by secondary forest and four plots within continuous closed mature forest. Vascular plant species were recorded in an area of 20 × 20 m2. Geometrid moths were attracted using lamps placed inside reflective gauze cylinders. Ninety-three species of vascular plants were recorded on the plots. Plant diversity increased in the course of forest regeneration from clearings and secondary forest to mature forest remnants and mature forest. This increase was visible in all vegetation strata as well as in the species number of Dicotyledoneae. The diversity of geometrid moths conversely decreased from early to late successional stages. A total of 2276 Geometridae representing 114 morphospecies were included in the study. Local values of Fisher's α varied from 10.3 to 18.3 on clearings and in secondary forest, whereas they remained below 8.0 in mature forest and mature forest remnants. There was a significant negative correlation between the diversity of Geometridae and the number of dicots, and of plant species in the shrub layer. Contrary to an expected positive correlation between the diversity of vascular plants and herbivorous geometrid moths, diversity patterns of these two groups are strongly diverging due to biogeographical and ecological factors differently affecting the two groups. The increase in plant diversity can chiefly be explained with an increase in epiphyte diversity which is related to the occurrence of suitable habitats in extensive moss layers on huge Ocotea usambarensis (Engl.) trees in the mature forest. The low diversity of geometrid moths in these forests may be connected to the isolation and relatively young age of the montane rain forests on Mt Kilimanjaro. Hence only a small number of moth species adapted to the cool and perhumid conditions within moist mature forest have so far immigrated into these habitats, and time was insufficient for the evolution of many new species. [ABSTRACT FROM AUTHOR]

Successional patches are a large component of forest ecosystems throughout the world and their vegetation composition is conditioned by multiple factors such as land use history, disturbances, environmental conditions and landscape context. We investigated the relative contribution of historical, environmental, biotic and spatial factors in determining vegetation composition and invasion by exotic species in secondary forest patches of Sierra de San Javier, Tucumán, Argentina. We estimated canopy cover for shrub, vine and tree species distributed over 51 patches with known land use history. We also recorded environmental, historical and spatial variables and used multivariate techniques to explore the relationship between forest composition and explanatory variables. Land use, time since abandonment, altitude, slope and cover of different strata were related to the vegetation pattern in the study site, and they were all significantly structured over space. Exotic species appeared to differ from natives in their response to explanatory variables. Overall, exotic species were dominant on the edges of young patches originated from herbaceous crops, but the total number of exotic species was related to the distance to urban areas and small farms identified as potential sources of exotic propagules. Vegetation composition of secondary forests in NW Argentina was related to historical and environmental factors, but spatial variables strongly influenced vegetation composition as well as the variation in explanatory variables. [ABSTRACT FROM AUTHOR]

Abstract Crassulacean acid metabolism (CAM), an advanced photosynthetic pathway conferring water conservation to plants in arid habitats, has enigmatically been reported in some species restricted to extremely wet tropical forests. Of these, epiphytic Bromeliaceae may possess absorbent foliar trichomes that hinder gas-exchange when wetted, imposing further limitations on carbon dioxide (CO2 ) uptake. The hypothesis that the metabolic plasticity inherent to CAM confers an ecological advantage over conventional C3 plants, when constant rainfall and mist might inhibit gas-exchange was investigated. Gas-exchange, fluorometry and organic acid and mineral nutrient contents were compared for the bromeliads Aechmea dactylina (CAM) and Werauhia capitata (C3 ) in situ at the Cerro Jefe cloud forest, Panama (annual rainfall > 4 m). Daily carbon gain and photosynthetic nutrient use efficiencies were consistently higher for A. dactylina , due to a greater CO2 uptake period, recycling of CO2 from respiration and a dynamic response of CO2 uptake to wetting of leaf surfaces. During the dry season CAM also had water conserving and photoprotective roles. A paucity of CAM species at Cerro Jefe suggests a recent radiation of this photosynthetic pathway into the wet cloud forest, with CAM extending diversity in form and function for epiphytes. [ABSTRACT FROM AUTHOR]

The article presents a study that examines the effect of natural vs. anthropogenic landscape matrices on the abundance of neotropical birds in forest sites. It evaluates the influence of three contrasting matrices on the relative abundance of 113 bird species in a subandean region. The results of the study suggest that structurally complex anthropogenic matrices have potential as management tools for bird conservation by complementing habitat protection and restoration.

Results presented in this paper demonstrate the relationship between two data sets from Mubwindi Swamp, south-west Uganda. The first data set is form a survey of dryland montane forest within the immediate catchment and the second is in the form of pollen spectra recovered from surface samples of sediment. Numerical analysis grouped pollen types encountered into five categories, according to their level of representivity when compared with abundances of the same taxa in the sampled vegetation; under representative, moderately under representative, representative, moderately over representative, and over representative. The northern part of Mubwindi Swamp also yielded a 5-m-long sequence of organic-rich sediments (core MB6) from which sub-fossil pollen and radiocarbon data have been previously obtained. This provides an opportunity to apply calibration factors derived from modern pollen-vegetation relationships to sub-fossil pollen data that were obtained from the same site. These calibration factors effectively down-weighted the influence of over representative pollen types and permitted the discrimination of a phase of forest disturbance that had not previously been so clearly visible in sub-fossil pollen data. [ABSTRACT FROM AUTHOR]

We estimated the live aboveground biomass (AGB) and soil nutrient pools of the Scalesia pedunculata monodominant tropical montane forest at 600 m above sea level on Santa Cruz, Galápagos, an isolated oceanic island. The estimated AGB was 60.4 Mg ha-1, which was considerably lower than that of other montane forests of similar climates elsewhere. Nutrient pools were ample for inorganic N, soluble P, and exchangeable cations. We suggest that the low AGB, in spite of the ample nutrients, is related to the absence of tall-statured climax species, that have high demands for nutrients (particularly N) to fix C, due to the isolation. [ABSTRACT FROM AUTHOR]

In 1987 particularly, but also in 1988, primaeval montane coniferous forests of northern Scandinavia experienced needle loss on an unprecedented scale, which affected the character of the entire landscape in certain regions. This study elucidates the dieback event for Norway spruce [Picea abies (L.) Karst.] in an area of the Swedish Scandes. The study includes visual assessment of percentage needle loss, age structure, radial growth and various environmental parameters, along altitudinal transects and within a larger sample plot. Frequency and magnitude of foliage damage were found to be related to elevation. The dieback process of closed forest stands was interpreted as a response to short-term climatic variability. Damage mainly developed during one of the coldest early winters (December-January 1986/7) of this century. In combination with sub-normal depth of the snow cover, the severe cold promoted exceptionally deep and persistent soil frost in spruce forest stands. It is hypothesized that damage was mainly due to winter/spring drought (frost-drought). Phenotypically closed forest stands may change in just a few years in response to cooling, a feature which has not been realized previously. The possibility of major retrogressive responses to short-term climatic events should therefore he considered in studies of historical biogeography and when modelling vegetation succession. The forest studied was probably established after a severe wind storm in 1837. The restocking process was facilitated by the post-Little Ice Age warming, but the stands are at present suffering severe dieback due to the recent cooling of the climate. The results stress the potential importance of short-term climatic disturbance in boreal forest succession. Reasonably, rapid cold-induced dieback of forest stands may have been a recurrent feature of Holocene forest history in the Boreal zone. [ABSTRACT FROM AUTHOR]

Eight newly developed polymorphic microsatellite markers are presented for Abies guatemalensis Rehder, an endangered tree endemic to Mexico and Central America. These microsatellite markers are useful for evaluating the population genetics of the species which is threatened by greenery poaching in natural populations. Novel conservation plans are needed to secure a more sustainable use strategy and to preserve the genetic diversity of the species. [ABSTRACT FROM AUTHOR]

We describe the isolation of 10 tetranucleotide microsatellites from the spot-throat using an enrichment protocol. All loci were highly variable with the number of alleles ranging from six to 20 and observed heterozygosity ranging from 0.410 to 0.940. Although all loci were in Hardy–Weinberg equilibrium, locus Mst95 showed significant homozygote excess in both surveyed populations, possibly a consequence of the presence of null alleles at this locus. These loci will be used to determine the extent to which spot-throat populations are isolated in order to help set conservation priorities for this ancient African lineage. [ABSTRACT FROM AUTHOR]

Considering the high energetic costs of maintaining constant body temperature, mammals must adjust their thermoregulatory behaviors in response to cold temperatures. Although primate daytime thermoregulation is relatively well studied, there is limited research in relation to nighttime strategies. To investigate how Skywalker hoolock gibbons (Hoolock tianxing) cope with the low temperatures found in montane forests, we collected sleep‐related behavior data from one group (NA) and a single female (NB) at Nankang (characterized by extensive tsaoko plantations) between July 2010 and September 2011, and one group (BB) at Banchang (relatively well‐managed reserve forest) between May 2013 and May 2015 in Mt. Gaoligong, Yunnan, China. The annual mean temperature was 13.3°C at Nankang (October 2010 to September 2011) and 13.0°C at Banchang (June 2013 to May 2015) with temperatures dropping below −2.0°C at both sites, making them the coldest known gibbon habitats. The lowest temperatures at both sites remained below 5.0°C from November to March, which we, therefore, defined as the "cold season". The hoolock gibbons remained in their sleeping trees for longer periods during the cold season compared to the warm season. Sleeping trees found at lower elevations and closer to potential feeding trees were favored during cold seasons at both sites. In addition, the gibbons were more likely to huddle together during cold seasons. Our results suggest that cold temperatures have a significant effect on the sleeping behavior of the Skywalker hoolock gibbon, highlighting the adaptability of this threatened species in response to cold climates. Research Highlights: We studied thermoregulatory sleeping behavior of two gibbon groups living in the coldest gibbon habitat across the world.Compared to warm seasons, gibbons stayed longer in their sleeping trees, sleeping at lower elevations and closer to potential feeding trees, and were more likely to huddle together during cold seasons.We call for more research regarding behavioral thermoregulatory responses of primates to cold climates. [ABSTRACT FROM AUTHOR]

Habitat loss is one of the main threats to wildlife. Therefore, knowledge of habitat use and preference is essential for the design of conservation strategies and identification of priority sites for the protection of endangered species. The yellow‐tailed woolly monkey (Lagothrix flavicauda Humboldt, 1812), categorized as Critically Endangered on the IUCN Red List, is endemic to montane forests in northern Peru where its habitat is greatly threatened. We assessed how habitat use and preference in L. flavicauda are linked to forest structure and composition. The study took place near La Esperanza, in the Amazonas region, Peru. Our objective was to identify characteristics of habitat most utilized by L. flavicauda to provide information that will be useful for the selection of priority sites for conservation measures. Using presence records collected from May 2013 to February 2014 for one group of L. flavicauda, we classified the study site into three different use zones: low‐use, medium‐use, and high‐use. We assessed forest structure and composition for all use zones using 0.1 ha Gentry vegetation transects. Results show high levels of variation in plant species composition across the three use zones. Plants used as food resources had considerably greater density, dominance, and ecological importance in high‐use zones. High‐use zones presented similar structure to medium‐ and low‐use zones; thus it remains difficult to assess the influence of forest structure on habitat preference. We recommend focusing conservation efforts on areas with a similar floristic composition to the high‐use zones recorded in this study and suggest utilizing key alimentation species for reforestation efforts. Research Highlights: Forest composition is more important than forest structure for Lagothrix flavicauda habitat preference in the northern Peruvian Andes.Zones highly used by L. flavicauda in the study site show similar floristic composition and natural regeneration of feeding plants. [ABSTRACT FROM AUTHOR]