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Soil bioturbation activity affects soil texture, bulk density, soil water content and redistribution of nutrients. All of these factors influence surface and subsurface sediment and hydrological processes, and thus are expected to shape the surface on large temporal scales. Previous studies have shown that the impact of bioturbation on these processes is not homogenous.However, the factors, which determine if bioturbation will positively or negatively affect the named processes, remain unknown. For this reason, the inclusion of bioturbation into erosion and landscape models have up until now been limited. The few models which include it in their algorithms assume a linear positive relationship between bioturbation rates, and erosion, soil mixing and vegetation cover.In our study, we tested the possibilities and limitations of including bioturbation into soil erosion modelling. We modelled the impact of bioturbation on sediment redistribution, surface runoff, subsurface runoff and infiltration capacity within several climate zones and identified environmental parameters determining the positive or negative impact of bioturbation on surface processes.Our study area was located along Chilean climate gradient. We measured the needed soil properties and location of burrows created by bioturbating animals in the field. Then we applied machine learning algorithms and used satellite data as predictors to upscale the soil properties and burrow distribution into the catchment. At each of the predicted burrow locations we adjusted the topography, soil properties and vegetation cover accordingly. We implemented the predicted parameters into a semi-empirical model and ran the model for a time period of 3 years under two conditions: With and without integrated bioturbation. We validated the model using sediment fences located at the base of each catchment.Model with integrated bioturbation activity had an R2 of 0.71 while a model without bioturbation activity had an R2 = 0.45. Bioturbation increased sediment redistribution in all but humid climate zone. The surface runoff increased in semi-arid zone while the infiltration capacity and subsurface runoff increased in the mediterranean and humid climate zone. Bioturbation increased sediment erosion at high and middle values of elevation, at high values of inclination and connectivity, and at low values of profile curvature. Bioturbation increased sediment accumulation at high values of surface roughness and topographic wetness index and at low values of vegetation cover.

Phenology, the seasonal timing of life events, is an essential component of biodiversity which partly results from species´ life cycle synchronisation to optimal seasonal moments1. The mechanisms involved are, however, complex2–4 and understudied which limits our ability to predict biodiversity responses to global change drivers5. Thermoregulation is crucial for shaping diversity patterns, particularly in ectotherms such as insects. Dark-bodied species are able to inhabit colder areas due to their higher absorbance of solar radiation – a pattern known as Thermal Melanism Hypothesis (TMH). Thermal melanism is well supported to drive spatial variation of insect diversity6, but whether it also may influence phenological patterns remains unexplored. Here we show, using a unique dataset of thousands of spatio-phenologically explicit dragonfly and damselfly assemblages, that dragonfly body colour lightness patterns respond to seasonal variation of solar radiation, with darker early- and late-season assemblages and lighter mid-season assemblages. This suggests that colour-based thermoregulation can determine insect phenology in relation to optimal seasonal conditions. We also show that the phenological pattern of dragonfly colour lightness advanced significantly over the last 30 years. Together with static nature of solar radiation, our results suggest that global warming may drive flight periods to suboptimal seasonal conditions. Our findings open a new research avenue for a more mechanistic understanding of phenology and spatio-phenological impacts of climate warming on insects and other ectotherms.

Our understanding of how biotic interactions influence animal community assembly is largely restricted to local systems due to the difficulty of obtaining ecologically meaningful assemblage data across large spatial extents. We used a unique dataset of thousands of spatio-phenologically high-resolution assemblages across three distinct European regions together with a functional diversity approach to understand community assembly of dragonflies and damselflies (Odonata), a group characterized by a pronounced competitive reproductive biology. We found that dragonfly, but not damselfly, assemblages were consistently overdispersed in the morphological traits driving inter-specific reproductive encounters, which supports the role of competition. As predicted by ecological theory, support for competition varied spatially and seasonally as a result of changes in temperature stress and niche packing. Our study provides uniquely consistent and general evidence for the role of competition in animal community assembly, and illustrates mechanistically how spatio-temporal diversity patterns arise from variation in assembly processes.

Recent small-scale and experimental studies have shown that colour lightness variation can have important physiological implications, with darker species having greater heating rates, as well as protection against pathogens and photooxidative damage. Using data for 41% (3,059) of all frog and toad species (Anura) from across the world, we reveal ubiquitous and strong clines of decreasing colour lightness towards colder regions and regions with higher pathogen pressure and UVB radiation. The relative importance of pathogen resistance was higher in the tropics and that of thermoregulation was higher in temperate regions. These functions strongly influenced colour lightness evolution in anurans and filtered for more similarly coloured species under climatic extremes, while concurrent mechanisms resulted in high within-assemblage variation in productive regions. The findings establish three fundamentally important functions of colour lightness that were previously unknown in anurans, and they substantially broaden support for colour lightness–environment relationships in ectotherms.

Bioturbating animals can affect physical and chemical soil properties on near-surface soil by either foraging for food or constructing suitable habitats. Thereby, bioturbation can influence the soil texture either sorting or mixing the different grain sizes clay, silt and sand during burrowing. Additionally, bioturbating animals can increase the macronutrients carbon (C), nitrogen (N) and phosphorus (P) through the transport of nutrients by vertically mixing the soil column and the addition of the bioturbators’ feces to the soil surface. To date, it is not clear how the effects of bioturbation on soil properties vary along an ecological gradient. Therefore, we compared the physical properties clay, silt and sand and the chemical contents of the macronutrients C, N and P for soil samples from mounds and the surrounding area as controls in three different climatic regions (arid, semi-arid and Mediterranean) of coastal Chile. To do so, we calculated the difference between the concentrations of paired mound and control samples. When comparing soil texture, we did not find significant differences between mound and control soil samples. For the macronutrient contents, the difference between mound and control C and N contents increased in the arid site and decreased in the two other research sites with increasing vegetation cover. Since we aimed to cover bioturbation patterns on a broader scale, we additionally compared our findings to other bioturbation studies performed in different biomes. Thereby, we found that other studies also show small differences in soil properties caused by bioturbation which are already sufficient to increase soil fertility.

Soil bioturbation activity affects soil texture, bulk density, soil water content and redistribution of nutrients. All of these parameters influences sediment redistribution, which shapes the earth surface. Hence it is important to include bioturbation into erosion models. However, up to present, the inclusion of bioturbation into erosion models was limited. This is because to realistically include bioturbation into the modelling, the interplay between bioturbation, sediment redistribution and environmental parameters is not understood. Here, we included bioturbation into a soil erosion model and interpreted the impacts of bioturbation on sediment redistribution. To do this, we measured the needed soil properties and location of burrows created by bioturbating animals in four research sites located along the Chilean climate gradient. Then, we parametrized a semi-empirical erosion model by applying machine learning algorithms to upscale soil properties and burrow distribution. We ran the model for a time period of 6 years under two conditions: With and without bioturbation. We validated the model using several sediment fences in the field. We estimated the modelled sediment redistribution and surface runoff in all climate zones. Lastly, we identified environmental parameters determining the positive or negative impact of bioturbation on sediment redistribution. We found that the model with integrated bioturbation performed much better (R2 = 0.71, RMSE = 0.63) than the model without integrated bioturbation (R2 = 0.17, RMSE = 1.18), meaning that model runs which considered bioturbation predicted the sediment redistribution more realistically. Furthermore, bioturbation increased sediment redistribution in all but the humid climate zone, especially in the Mediterranean zone. The quantity of sediment redistributed due to bioturbation was reliant on an interplay between elevation, slope, surface roughness and sink connectivity. Overall, bioturbation enhances sediment erosion in areas where more erosion is expected, and enhances sediment accumulation in areas which are more prone to accumulate sediment. In other words, considering bioturbation when studying earth surface evolution means an amplification of existing tendencies in sediment redistribution, and leads to a faster hillslope relief equalisation.

Latitudinal body size-clines are primarily discussed in the context of thermoregulation, sensu Bergmann. However, body size patterns are ambiguous in ectotherms and this heterogeneity remains poorly understood. We hypothesised that the contrasting effects of thermoregulation and resource constraints obscure latitude–size relationships. Using data for 43% of all odonate species, we tested whether body size increases with decreasing temperature and increasing productivity in phylogenetically and spatially comparative analyses. We found strong but contrasting effects for temperature between Anisoptera and Zygoptera and consistent positive effects for productivity that explained 35%–57% of body size variation. We concluded that temperature, productivity, and conservatism in size-based thermoregulation synergistically determine the distribution of ectotherms, while the taxon-specific importance of these factors can lead to contrasting results and weak latitude–size relationships. Our results reinforce the importance of body size as a determinant of species distributions and responses to climate change.

Although macroecology is a well-established field, much remains to be learned about the large-scale variation of fungal traits. We conducted a global analysis of mean fruit body size of 59 geographical regions worldwide, comprising 5340 fungal species exploring the response of fruit body size to latitude, resource availability and temperature. The results showed a hump-shaped relationship between mean fruit body size and distance to the equator. Areas with large fruit bodies were characterised by a high seasonality and an intermediate mean temperature. The responses of mutualistic species and saprotrophs were similar. These findings support the resource availability hypothesis, predicting large fruit bodies due to a seasonal resource surplus, and the thermoregulation hypothesis, according to which small fruit bodies offer a strategy to avoid heat and cold stress and therefore occur at temperature extremes. Fruit body size may thus be an adaptive trait driving the large-scale distribution of fungal species.

Recent reports of insect decline highlight the need for extensive large-scale insect monitoring. However, obtaining abundance or species richness data at high spatial and temporal resolution is difficult due to personnel, maintenance, and post-processing costs as well as ethical considerations. Non-invasive automated insect monitoring systems could provide a solution to address these constraints. However, every new insect monitoring design needs to be evaluated with respect to reliability and bias based on comparisons with conventional methods.In this study, we evaluate the effectiveness of an automated moth trap (AMT), built from off-the-shelf-hardware, in capturing variations in moth abundance, by comparing it to a conventional, lethal trap. Both trap types were operated five times on 16 plots from the beginning of July 2021 to the end of August 2021.Moth abundance scaled isometrically between the two trap types. Consequently, the respective seasonal patterns in abundance determined over the monitoring period were similar.The AMT samples phenological patterns using a robust and non-lethal method. However, an initial quantitative in-field test revealed that its long-term applicability must be preceded by several adjustments to the power supply and to data transfer. Depending on the software implementation, the AMT can be used to address a broad range of research questions while also reducing both energy expenditure and the disturbance of non-target animals.

Climate change influences the global and regional distribution of many species. For thermophilic insects, range expansions towards the north and to higher elevations are expected in the course of climatic warming across the Northern Hemisphere. The distribution of the European mantis (Mantis religiosa) has recently expanded from Mediterranean regions in France to Hesse in central Germany. This is interpreted as a response to rising mean temperatures, and further northward expansion is expected to occur with increasing climate warming. In this study, potential changes in the regional distribution across Hesse were modeled for Mantis religiosa using the present distribution and climate across Europe as the baseline. We estimated potential changes in the regional distribution for two time periods until 2080 based on two climate change scenarios. The results showed that the current range of M. religiosa in Hesse is smaller than expected based on its climatic niche, i.e., the distribution is not in equilibrium with the present climate. With climate warming the model predicts an expansion of the potential distribution for the period 2041–2060. For the period 2061–2080, our model predicts, however, a range contraction in spite of continued warming. This unexpected result warrants further investigation in order to elucidate whether the ongoing climate change may have negative consequences for thermophilic species such as M. religiosa.

Several studies on wind turbine collision mortality in raptors suggest a bias towards adult birds, while sex-biased mortality has not yet been documented. We compared collision mortality in relation to all known causes of mortality and in relation to demographic data for the German population of the White-tailed Eagle and found collision mortality to be sex biased but not age biased. We suggest that these contrasting results may in part be explained by the lack of baseline data about the demographic structure of surveyed populations in previous studies. Our results stress the importance of baseline data for inferring demographic consequences of wind turbine collision mortality.

The most basic behavioural states of animals can be described as active or passive. However, while high-resolution observations of activity patterns can provide insights into the ecology of animal species, few methods are able to measure the activity of individuals of small taxa in their natural environment. We present a novel approach in which the automated VHF radio-tracking of small vertebrates fitted with lightweight transmitters (< 0.2 g) is used to distinguish between active and passive behavioural states.A dataset containing > 3 million VHF signals was used to train and test a random forest model in the assignment of either active or passive behaviour to individuals from two forest-dwelling bat species (Myotis bechsteinii (n = 50) and Nyctalus leisleri (n = 20)). The applicability of the model to other taxonomic groups was demonstrated by recording and classifying the behaviour of a tagged bird and by simulating the effect of different types of vertebrate activity with the help of humans carrying transmitters. The random forest model successfully classified the activity states of bats as well as those of birds and humans, although the latter were not included in model training (F-score 0.96–0.98).The utility of the model in tackling ecologically relevant questions was demonstrated in a study of the differences in the daily activity patterns of the two bat species. The analysis showed a pronounced bimodal activity distribution of N. leisleri over the course of the night while the night-time activity of M. bechsteinii was relatively constant. These results show that significant differences in the timing of species activity according to ecological preferences or seasonality can be distinguished using our method.Our approach enables the assignment of VHF signal patterns to fundamental behavioural states with high precision and is applicable to different terrestrial and flying vertebrates. To encourage the broader use of our radio-tracking method, we provide the trained random forest models together with an R-package that includes all necessary data-processing functionalities. In combination with state-of-the-art open-source automated radio-tracking, this toolset can be used by the scientific community to investigate the activity patterns of small vertebrates with high temporal resolution, even in dense vegetation.

Burrowing animals influence surface microtopography and hillslope sediment redistribution, but changes often remain undetected due to a lack of autonomous high resolution field monitoring techniques. In this study we present a new approach to quantify microtopographic variations and surface changes caused by burrowing animals and rainfall-driven erosional processes applied to remote field plots in arid and mediterranean Chile. We compared the mass balance of redistributed sediment within plot areas affected and not affected by burrowing animals, quantified the cumulative sediment redistribution caused by animals and rainfall, and upscaled the results to the hillslope scale. The new instrument showed a very good detection accuracy. The cumulative sediment redistribution within areas affected by burrowing animals was higher (−10.44 cm3 cm−2 year−1) in the mediterranean than the arid climate zone ( −1.41 cm3 cm−2 year−1). Daily sediment redistribution during rainfall within areas affected by burrowing animals were up to 350 % / 40 % higher in the mediterranean / arid zone compared to the unaffected areas, and much higher than previously reported in studies not based on continuous microtopographic monitoring. Furthermore, 38 % of the sediment eroding from the burrows accumulated within the burrow entrance while 62 % was incorporated into overall hillslope sediment flux. The cumulative sediment excavation by the animals was 14.62 cm3 cm−2 year−1 in the mediterranean and 16.41 cm3 cm−2 year−1 in the arid climate zone. Our findings can be implemented into long-term soil erosion models that rely on soil processes but do not yet include animal-induced surface processes on microtopographical scales in their algorithms.

Burrowing animals influence surface microtopography and hillslope sediment redistribution, but changes often remain undetected due to a lack of automated high-resolution field monitoring techniques. In this study, we present a new approach to quantify microtopographic variations and surface changes caused by burrowing animals and rainfall-driven erosional processes applied to remote field plots in arid and Mediterranean climate regions in Chile. We compared the mass balance of redistributed sediment between burrow and burrow-embedded area, quantified the cumulative sediment redistribution caused by animals and rainfall, and upscaled the results to a hillslope scale. The newly developed instrument, a time-of-flight camera, showed a very good detection accuracy. The animal-caused cumulative sediment excavation was 14.6 cm3 cm−2 yr−1 in the Mediterranean climate zone and 16.4 cm3 cm−2 yr−1 in the arid climate zone. The rainfall-related cumulative sediment erosion within burrows was higher (10.4 cm3 cm−2 yr−1) in the Mediterranean climate zone than the arid climate zone (1.4 cm3 cm−2 yr−1). Daily sediment redistribution during rainfall within burrow areas was up to 350 %(40 %) higher in the Mediterranean (arid) zone compared to burrow-embedded areas and much higher than previously reported in studies that were not based on continuous microtopographic monitoring. A total of 38 % of the sediment eroding from burrows accumulated within the burrow entrance, while 62 % was incorporated into hillslope sediment flux, which exceeds previous estimations 2-fold. On average, animals burrowed between 1.2–2.3 times a month, and the burrowing intensity increased after rainfall. This revealed a newly detected feedback mechanism between rainfall, erosion, and animal burrowing activity, likely leading to an underestimation of animal-triggered hillslope sediment flux in wetter climates. Our findings hence show that the rate of sediment redistribution due to animal burrowing is dependent on climate and that animal burrowing plays a larger than previously expected role in hillslope sediment redistribution. Subsequently, animal burrowing activity should be incorporated into soil erosion and landscape evolution models that rely on soil processes but do not yet include animal-induced surface processes on microtopographical scales in their algorithms.

Insect populations have become increasingly threatened during the last decades due to climate change and landuse intensification. Species characteristics driving these threats remain poorly understood. Trait-based analyses provide a straight-forward approach to gain a mechanistic understanding of species' extinction risk, guiding the development of conservation strategies. We combined morphological traits and phylogenetic relationship for 332 European species of butterflies and 115 species of odonates (dragon and damselflies) to model their red list status via phylogenetically controlled ordered logistic regression. We hypothesized that extinction risk increases with increasing body volume and wing area, decreasing range size, and is larger for brighter species. All investigated traits exhibited a strong phylogenetic signal. When controlling for phylogenetic relationship, we found that extinction risk of butterflies increased with decreasing range size. The extinction risk of odonates showed no relationship with the selected traits. Our results show that there is no universal trait defining the extinction risk of our investigated insect taxa. Furthermore, evolutionary history, measured as the phylogenetically predicted part of our analyzed traits, poorly predicted extinction risk. Our study confirms the focus of conservation measures on European butterfly species with small range sizes.

Made available in DSpace on 2022-04-28T19:44:08Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-09-02 The amount of carbon stored in deadwood is equivalent to about 8 per cent of the global forest carbon stocks1. The decomposition of deadwood is largely governed by climate2–5 with decomposer groups—such as microorganisms and insects—contributing to variations in the decomposition rates2,6,7. At the global scale, the contribution of insects to the decomposition of deadwood and carbon release remains poorly understood7. Here we present a field experiment of wood decomposition across 55 forest sites and 6 continents. We find that the deadwood decomposition rates increase with temperature, and the strongest temperature effect is found at high precipitation levels. Precipitation affects the decomposition rates negatively at low temperatures and positively at high temperatures. As a net effect—including the direct consumption by insects and indirect effects through interactions with microorganisms—insects accelerate the decomposition in tropical forests (3.9% median mass loss per year). In temperate and boreal forests, we find weak positive and negative effects with a median mass loss of 0.9 per cent and −0.1 per cent per year, respectively. Furthermore, we apply the experimentally derived decomposition function to a global map of deadwood carbon synthesized from empirical and remote-sensing data, obtaining an estimate of 10.9 ± 3.2 petagram of carbon per year released from deadwood globally, with 93 per cent originating from tropical forests. Globally, the net effect of insects may account for 29 per cent of the carbon flux from deadwood, which suggests a functional importance of insects in the decomposition of deadwood and the carbon cycle. Ecosystem Dynamics and Forest Management Group School of Life Sciences Technical University of Munich Berchtesgaden National Park Epidemiology Biostatistics and Prevention Institute University of Zurich Southern Research Station USDA Forest Service Field Station Fabrikschleichach University of Würzburg Biological Sciences University of Toronto Scarborough Fenner School of Environment and Society The Australian National University Department of Biogeography University of Bayreuth Department of Disturbance Ecology University of Bayreuth Instituto de Ecología Regional CONICET-Universidad Nacional de Tucumán Department of Animal Ecology and Tropical Biology University of Würzburg Laboratory of Environmental Microbiology Institute of Microbiology The Czech Academy of Sciences Agricultural and Natural Resources Research Centre of Mazandaran Lancaster Environment Centre Lancaster University Universidade Federal de Lavras Department of Biodiversity Conservation Goethe-University Frankfurt Bavarian Forest National Park CIRAD UMR Ecologie des Forêts de Guyane (EcoFoG) AgroParisTech CNRS INRA Universite des Antilles Universite de Guyane Environmental Change Institute University of Oxford Grassland Vegetation Lab Federal University of Rio Grande do Sul Faculty of Environmental Sciences and Natural Resource Management Norwegian University of Life Sciences Institute of Ecology and Botany Centre for Ecological Research Institute for Wildlife Management and Nature Conservation Hungarian University of Agriculture and Life Sciences Animal Ecology University of Marburg École d’Ingénieurs de Purpan Université de Toulouse UMR 1201 Dynafor Ecosystem Science and Management Program University of Northern British Columbia Laboratory of Applied Ecology University of Abomey-Calavi Department of Ecology University of Granada Réserves Naturelles de France Royal Alberta Museum Conservation Ecology University of Marburg Science and Engineering Faculty Queensland University of Technology Centre for the Environment Institute for Future Environments Forest Research Institute Malaysia International Institute of Tropical Forestry USDA Forest Service Forest Entomology Swiss Federal Research Institute WSL Evolutionary Zoology University of Salzburg Natural Resources Canada Canadian Forest Service Eurofins Ahma Oy Department of Plant Systematics University of Bayreuth Department of Wildlife Fish and Environmental Studies Swedish University of Agricultural Sciences Applied Landscape Ecology Chuo University School of Forest Sciences University of Eastern Finland School of Agricultural Forest and Food Sciences Bern University of Applied Sciences CAS Key Laboratory for Plant Diversity and Biogeography of East Asia Kunming Institute of Botany Chinese Academy of Sciences ECNU-Alberta Joint Lab for Biodiversity Study Tiantong National Station for Forest Ecosystem Research East China Normal University Institute of Biological Sciences University of the Philippines Los Banos Department of Thermodynamics Universidad Nacional del Nordeste Tropical Forests and People Research Centre University of the Sunshine Coast Forest Ecosystem Monitoring Laboratory National University of Mongolia School of Environment and Science Griffith University School of Biological Earth and Environmental Sciences University College Cork Edge Hill University Institute of Forestry Tribhuvan University Institute of Evolution University of Haifa Scion (New Zealand Forest Research Institute) School of Forestry University of Canterbury Institute of Zoology University of Hamburg Faculté des Sciences Université d’Antananarivo Tropical Biodiversity and Social Enterprise Departamento de Ecologia Universidade Estadual Paulista Ecology Group University Erlangen-Nuremberg H. J. Andrews Experimental Forest Environmental and Conservation Sciences Murdoch University Environmental Futures Research Institute Griffith University Ashoka Trust for Research in Ecology and the Environment ARC Centre for Forest Value University of Tasmania Terrestrial Ecology Research Group School of Life Sciences Technical University of Munich EcoBank Team National Institute of Ecology College of Forestry Beijing Forestry University Departamento de Ecologia Universidade Estadual Paulista

The increasing number of wind farms for energy production raises concerns about their effects on wildlife and particularly on birds. To date it is unclear whether models that combine data on wind turbine densities and habitat suitability can explain the actual spatial occurrence of collision fatalities and how well these models perform in comparison to models including measures of bird population densities (e.g., the distribution and density of nest sites). Here we analysed whether collision mortality increases with wind turbine density and whether a high population density or habitat suitability in the vicinity of wind turbines amplifies the effect of wind turbine density on collision mortality. We combined opportunistic records of dead White-tailed Eagles by the public in Northeast Germany during the period 2003 to 2014 with data on the distribution of wind turbines, nest sites and habitat suitability. As expected, wind turbine density was a strong predictor of collision mortality. In addition, we found that wind turbine density and habitat suitability had synergistic effects on collision mortality, so that the effect of wind turbine density was amplified in areas of high habitat suitability. Moreover, combining wind turbine density and habitat suitability allowed for better predictions of collision mortality than combining wind turbine density and nest site density. These results suggest that assessments of the spatial occurrence of collision fatalities based on models that combine data on wind turbine densities and habitat suitability can be useful for the strategic planning of wind farm development on regional scales. In particular, our study highlights that wind turbines should not be placed in core population areas of vulnerable bird species because synergies between wind turbine densities and habitat suitability may cause disproportionate increases in mortality. This might undermine the positive effects of parallel conservation efforts.

Herbivores and mycorrhizal fungi interactively influence growth, resource utilization, and plant defense responses. We studied these interactions in a tritrophic system comprising Quercus robur, the herbivore Lymantria dispar, and the ectomycorrhizal fungus Piloderma croceum under controlled laboratory conditions at the levels of gene expression and carbon and nitrogen (C/N) allocation. Taking advantage of the endogenous rhythmic growth displayed by oak, we thereby compared gene transcript abundances and resource shifts during shoot growth with those during the alternating root growth flushes. During root flush, herbivore feeding on oak leaves led to an increased expression of genes related to plant growth and enriched gene ontology terms related to cell wall, DNA replication, and defense. C/N-allocation analyses indicated an increased export of resources from aboveground plant parts to belowground. Accordingly, the expression of genes related to the transport of carbohydrates increased upon herbivore attack in leaves during the root flush stage. Inoculation with an ectomycorrhizal fungus attenuated these effects but, instead, caused an increased expression of genes related to the production of volatile organic compounds. We conclude that oak defense response against herbivory is strong in root flush at the transcriptomic level but this response is strongly inhibited by inoculation with ectomycorrhizal fungi and it is extremely weak at shoot flush.

Tropical montane forests, particularly Andean rainforest, are important ecosystems for regional carbon and water cycles as well as for biological diversity and speciation. Owing to their remoteness, however, ecological key-processes are less understood as in the tropical lowlands. Remote sensing allows modeling of variables related to spatial patterns of carbon stocks and fluxes (e.g., biomass) and ecosystem functioning (e.g., functional leaf traits). However, at a landscape scale most studies conducted so far are based on airborne remote sensing data which is often available only locally and for one time-point. In contrast, multispectral satellites at moderate spectral and spatial resolutions are able to provide spatially continuous and repeated observations. Here, we investigated the effectiveness of Landsat-8 imagery in modeling tropical montane forest biomass, its productivity and selected canopy traits. Topographical, spectral and textural metrics were derived as predictors. To train and validate the models, in-situ data was sampled in 54 permanent plots in forests of southern Ecuador distributed within three study sites at 1000 m, 2000 m and 3000 m a.s.l. We used partial least squares regressions to model and map all response variables. Along the whole elevation gradient biomass and productivity models explained 31%, 43%, 69% and 63% of variance in aboveground biomass, annual wood production, fine litter production and aboveground net primary production, respectively. Regression models of canopy traits measured as community weighted means explained 62%, 78%, 65% and 65% of variance in leaf toughness, specific leaf area, foliar N concentration, and foliar P concentration, respectively. Models at single study sites hardly explained variation in aboveground biomass and the annual wood production indicating that these measures are mainly determined by the change of forest types along with elevation. In contrast, the models of fine litter production and canopy traits explained between 8%–85% in variation depending on the study site. We found spectral metrics, in particular a vegetation index using the red and the green band to provide complementary information to topographical metrics. The model performances for estimating leaf toughness, biochemical canopy traits and related fine litter production all improved when adding spectral information. Our findings therefore revealed that differences in fine litter production and canopy traits in our study area are driven by local changes in vegetation edaphically induced by topography. We conclude that Landsat-derived metrics are useful in modeling fine litter production and biochemical canopy traits, in a topographically and ecologically complex tropical montane forest.