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On 16 May 2021, a storm petrel was photographed on a pelagic trip in the Benguela Current off Cape Town, South Africa, exhibiting the diagnostic features of Pincoya Storm Petrel Oceanites pincoyae. This sighting occurred far from other records, the closest being approximately 7500 km away. The record, therefore, requires us to reassess our understanding of the movements and ecology of Pincoya Storm Petrel, which was previously known only from shallow waters in fjords and adjacent seas in south-central Chile. Pincoya Storm Petrel is considered Data Deficient by the International Union for Conservation of Nature (IUCN), the breeding range remains unknown, and the population was estimated to number only around 3000 individuals. While Pincoya Storm Petrel is recognised as a valid species by the International Ornithological Congress (IOC), eBird/Clements checklists, and the South American Classification Committee, its taxonomic status has been questioned. This sighting of a bird with all the features of Pincoya Storm Petrel distant from previous sightings, and in a markedly different ecological setting, may lead us to re-evaluate our understanding of species limits and phenotypic variation in Oceanites storm petrels. Further research to collect phenotypic, phylogenetic, and phenological data will allow us to re-examine species boundaries in Oceanites and enhance our understanding of this fascinating genus. [ABSTRACT FROM AUTHOR]

In terms of contribution to global food security, this study aimed to build a crop monitoring system for within-season yield prediction of US corn and soybeans by using the Moderate Resolution Imaging Spectroradiometer (time-series data, which consists of three essential core algorithms (crop phenology detection, early crop classification, and crop yield prediction methods)). Within-season predictions for 2018-2022 were then made to evaluate the performance of the proposed system by comparing it with the United States Department of Agriculture's (USDA's) monthly forecasts and the fixed statistical data. The absolute percentage errors of the proposed system for predicting national-level yield and production were less than 5% for all simulation years as of day of year (DOY) 279. The prediction accuracy as of DOY 247 and DOY 279 were comparable to the USDA's forecasts. The proposed system would enable us to make a comprehensive understanding about overview of US corn and soybean crop condition by visualizing detail spatial pattern of good- or poor harvest regions on a within-season basis. [ABSTRACT FROM AUTHOR]

In this long-term study, the timing of autumn migration, stopover duration, wing and third primary length, body mass, fat load, and pectoral muscle of the Common Blackbird (Turdus merula) were studied between 1998 and 2022 in Tömörd, Hungary. We found a significant increase in Common Blackbirds passing through the study site. There was no substantial difference between the timings of autumn migration in the two sexes. Still, the adults started their migration slightly later than juveniles. This timing was unchanged between 1998 and 2022, indicating that juveniles and adults of both sexes use the same adaptation strategy to determine the departure time. We found that wing length slightly but significantly decreased in both age and sex groups, whereas there was an increase in the length of the third primary during the study period. In our view, these wing morphology changes cannot be explained by local adaptations but by a change in the population composition: most individuals captured are short-distance migrants. Our results indicated that body mass and condition of all groups increased from September to November within a year, which can be interpreted in two ways: on the one hand, it could be caused by an increase in the proportion of adults, and on the other hand, there could be an increase in the proportion of Common Blackbirds arriving from territories to the north of the Pannonian region as the autumn migration progresses. The similarity in changes in the phenology and morphological traits of the different age and sex groups during the study period emphasizes that environmental change caused no detectable intraspecific selection pressures. [ABSTRACT FROM AUTHOR]

Vegetation phenology is an important indicator of environmental change and strongly connected to forest ecosystem productivity change. This study aimed to analyse the pattern of phenological variations derived from digital imagery for the interpretation of ecosystem productivity. For 2014, 2015 and 2016, the seasonal phenological development of savanna was analysed by using towerbased imagery from a digital camera. The green excess index (GEI) was the best at representing the phenological transition dates (PTDs) and useful for investigating the gross primary production (GPP) in the savanna ecosystem. There was a significant correlation between the monthly pattern of the strength of green (Sgreen), green excess index (GEI) and vegetation contrast index (VCI) and GPP throughout the year. Additionally, the annual pattern of colour indices had significant relationship (p < 0.05) with GPP but this was not seasonal. The air temperature (air T) and soil temperature (soil T) were strongly significantly correlated (p < 0.001) with the start of growing season (SGS) and caused the advance in green-up and the timing of the start of the growing season in 2014 and 2016. The short growing season length (GSL) had an impact on the productivity. The colour indices from the digital camera images not only provided the phenological pattern of a forest canopy but also revealed the forest ecosystem productivity by showing the response to environmental factors. Our results indicate that daily continuous digital camera images might be useful for ecologists to use as a tool for future prediction of the long-term phenological modelling. [ABSTRACT FROM AUTHOR]

Urban vegetation phenology is important for understanding the relationship between human activities on urban ecosystems and carbon cycle. The relationship between urban and rural vegetation phenology and environmental and meteorological factors were studied across urban-rural gradients. However, the relationship of intra-urban urbanization intensity (UI) gradients on vegetation at the start of season (SOS) is unclear. Here, we used remote sensing data to quantitatively assess the relationship of vegetation SOS to UI gradients at mid-high latitudes in the northern hemisphere. The results showed that urban area vegetation SOS widely presented earlier than for rural area vegetation. Across the cities we investigated the extent UI gradient was prevalent as a threshold (33.2% ± 2.3%) of surface temperature to SOS advance enhancement and offset. At low urbanization enhanced surface temperature on sos advances, while at high urbanization offset surface temperature on SOS advances. Overall, UI demonstrated a nonlinear relationship with sos. The results of this study suggest that there may be thresholds of impact on vegetation SOS in future global climate and environment change processes, where opposite effects can occur below and above thresholds. [ABSTRACT FROM AUTHOR]

Phenology is the study of recurrent biological events of animals and plants. In this article, we trace the history of phenological studies, understand the factors that drive phenology, discuss various ways one can observe phenological events, and how these observations are important and cost-effective ways to detect signatures of climate change. Finally, we discuss how using the latest technology, we can contribute to furthering phenological studies. [ABSTRACT FROM AUTHOR]

The study of vegetative and reproductive phenophases of plants is critical for understanding aspects related to plant behavior in different environments. In the tropics, there is a gap of understanding related to plant phenology since the theoretical framework on the topic has been built from perspectives of the temperate region. Furthermore, there are few studies in tropical regions influenced by anthropic conditions, which may be important for understanding these issues in the face of future climate scenarios. This study aimed to describe the vegetative and reproductive phenology of trees in an urban subtropical forest community and to test the influence of climatic variables on the tree community. In an urban forest fragment in Rio Grande do Sul, Brazil, eight individuals of locally dominant species were monitored: Allophylus edulis, Casearia sylvestris, Guarea macrophylla, Mimosa bimucronata, Myrsine coriacea, Myrsine umbellata, Schinus glandulosum, and Schinus terebinthifolia. The monitoring occurred every two weeks, for two years, with the recording of the presence of leaf flushing, leaf shedding, flowering, and fruiting phenophases for each tree. The seasonality of the species was tested using the Rayleigh test. We described the common pattern of community phenological activity by a Principal Component Analysis. Finally, we correlated the common patterns of each phenophase in the community with climatic variables of total precipitation, average temperature, and day length. All species showed a non-uniform phenological pattern for the evaluated phenophases despite the variable intensity. We evidenced common patterns for the community only for the vegetative phenophases. The reproductive phenophases of flowering and fruiting present themselves independently among species in the community. Finally, we identified influences only of temperature and day length on the vegetative phenophases. [ABSTRACT FROM AUTHOR]

Climatic conditions can influence plant reproduction directly, but also via changes in plant traits, interactions with animals, and the surrounding environment. Such indirect effects can often be complex and involve multiple steps including climatic effects on interacting species, and on the context in which these interactions occur. The joint effects of climatic variation and indirect effects in terms of plant-animal interactions have sometimes been assessed at larger spatial scales. However, less is known about how microclimatic variation affects within-population variation in reproductive performance, in spite of that it is becoming increasingly clear that variation in climatic conditions can occur over very short distances. We studied the direct and indirect effects of microclimate on within-population variation in reproductive performance of the plant Gentiana pneumonanthe in presence of the myrmecophagous and seed predator butterfly Phengaris alcon. We found that microclimatic effects on plant performance were mainly indirect, and that effects of temperature and moisture were interactive. The number of seeds per flower of G. pneumonanthe decreased in cold and moist microsites, and these effects were mediated by an increased oviposition by P. alcon in these microsites. The effects of soil temperature and moisture on the incidence of oviposition and plant performance were mediated by effects on plant phenology, density and phenology of neighbouring host plants, and host ant abundance. Plants that flowered earlier and where host ants were more abundant, and especially plants surrounded by fewer and later-flowering neighbours, produced fewer seeds per flower because of a higher incidence of oviposition. Our results demonstrate that effects of microclimatic variation on plant reproductive performance can be mostly indirect and largely mediated by species interactions. These findings highlight that among individual variation in small-scale environmental conditions within populations can cause variation in individual plant performance through multiple pathways. [ABSTRACT FROM AUTHOR]

Shifts in plant phenology associated with climate change have received unprecedented attention from land managers, policymakers, and the scientific community, with important implications for the structure and function of the biosphere. Eddy covariance (EC) has been used to measure carbon exchange between the land surface and atmosphere, which provides an opportunity to describe the seasonality of ecosystem processes. Using BASE flux products provided by the AmeriFlux network and a non-linear modeling approach, this study developed a vegetation carbon phenology (VCP) dataset, which we termed VCPNET (version 1.0). VCPNET was developed with fine spatial and temporal scales for a total of 87 EC sites (2820 site-years of data) across North America, including nine vegetation types. We extracted phenology metrics by site to provide long-term VCP metrics across these ecosystems. Analyses revealed significant differences in photosynthetic capacity and respiration rate-derived VCP metrics across the landscape, as well as differences associated with whether daily cumulative or half-hourly maximum measurements were used. Daily carbon fluxes may be more consistent in simulating phenology behavior than 30-min maximum fluxes across all vegetation types, except in sites classified as Grassland. Overall vegetation types, the seasonality of photosynthetic capacity may exert a larger control on the net carbon uptake of the ecosystem compared to the respiration rate. Thus, model-estimated photosynthesis-activated seasons may better represent true phenology, particularly the development of above- and below-ground plant biomass in tree-covered areas, which is crucial in forecasting ecosystem carbon sequestration. In addition, a nonlinear model can robustly capture day-to-day variation in carbon flux; however, precise simulation of phenological patterns with multiple peaks, typically observed in disturbed ecosystems, must be addressed during model optimization. The cross-ecosystem phenology metrics provided by VCPNET could be utilized for regional-global analysis and calibration of satellite-based vegetation indices, which accurately scale land surface phenology. Our findings provide a prospective tool for a deeper understanding of ecosystem function, allowing a direction and foundation for optimizing phenology models and algorithms and ultimately contributing to developing new ecological theories and practices in response to climate change. [Display omitted] • VCPNET is a vegetation phenology dataset developed using AmeriFlux data. • Phenological metrics derived from daily cumulative flux have higher ecological utility than shorter time scales. • Seasonality in photosynthetic capacity alters ecosystem C uptake more than respiration. • VCPNET can improve the scaling of land surface phenology. [ABSTRACT FROM AUTHOR]

Changes in climate can greatly affect the phenology of plants, which can have important feedback effects, such as altering the carbon cycle. These phenological feedback effects are often induced by a shift in the start or end dates of the growing season of plants. The normalized difference vegetation index (NDVI) serves as a straightforward indicator for assessing the presence of green vegetation and can also provide an estimation of the plants' growing season. In this study, we investigated the effect of soil temperature on the timing of the start of the season (SOS), timing of the peak of the season (POS), and the maximum annual NDVI value (PEAK) in subarctic grassland ecosystems between 2014 and 2019. We also explored the impact of other meteorological variables, including air temperature, precipitation, and irradiance, on the inter-annual variation in vegetation phenology. Using machine learning (ML) techniques and SHapley Additive exPlanations (SHAP) values, we analyzed the relative importance and contribution of each variable to the phenological predictions. Our results reveal a significant relationship between soil temperature and SOS and POS, indicating that higher soil temperatures lead to an earlier start and peak of the growing season. However, the Peak NDVI values showed just a slight increase with higher soil temperatures. The analysis of other meteorological variables demonstrated their impacts on the inter-annual variation of the vegetation phenology. Ultimately, this study contributes to our knowledge of the relationships between soil temperature, meteorological variables, and vegetation phenology, providing valuable insights for predicting vegetation phenology characteristics and managing subarctic grasslands in the face of climate change. Additionally, this work provides a solid foundation for future ML-based vegetation phenology studies. • Studied soil temperature's impact on vegetation phenology in subarctic grasslands. • Linear models leave much variance unexplained, prompting a machine learning approach. • Observed that higher soil temperatures result in an earlier start of the season. • Meteorological variables have the largest impact on plant growth based on SHAP values. • Demonstrated that soil temperature is responsible for intra-annual variability. [ABSTRACT FROM AUTHOR]

Plant phenology is the study of cyclical events in a plant life cycle such as leaf bud burst, flowering, and fruiting. In this article the problem of olive phenology prediction is addressed through the use of Deep Learning. Although Neural Networks have already been used in this area, to the best of our knowledge, this is the first implementation of Probabilistic Bayesian Neural Networks for olive phenology prediction. This architecture gives particular emphasis to estimating the model uncertainty, both aleatoric and epistemic. The Bayesian Inference method, more precisely the Variational Inference one, is compared with the Monte Carlo Dropout technique, which is known to be a less computationally intensive approximation of Variational Inference. For validation purposes, models performance is compared to the state-of-the-art results. • Novel approach to ML-based olive phenology modeling. • Model uncertainty estimation using Bayesian theory within a Deep Learning framework. • Comparison between Variational Inference and Monte Carlo Dropout implementations. • Proven usefulness of the target feature re-labeling during the training phase. • Competitive results with state-of-the-art models. [ABSTRACT FROM AUTHOR]

For organisms living in seasonal environments, timing of breeding is key to ensuring reproductive success. Accordingly, temperate and polar seabird species follow seasonal pulses, matching their breeding events with peaks in ocean productivity. However, the seasonality of breeding has been much less explored in tropical seabirds. Here, we report seasonal variation in oceanography that affects reproductive success of the Brown Booby Sula leucogaster, a species widely distributed in the tropics. We monitored 61 nests during the 2019 breeding season at Bona Island, Gulf of Panama, and collected remote-sensing information for upwelling, sea-surface temperature, rainfall, chlorophyll-α concentration, wind speed, and wind direction. We used egg/chick survival probability and a sliding-window statistical approach to assess temporal changes in reproductive success. Maximum chlorophyll-α concentrations (linear and quadratic expressions) had the strongest influence over survival probability in the two to three weeks prior to the death of the egg/chick. After model averaging, we found that survival probability was positively correlated with maximum chlorophyll-α (confidence interval CI(β) = 0.19 to 2.54 mg/m³) and negatively correlated with (maximum chlorophyll-α)² (CI(β) = −4.19 to −0.31 mg/m³). In addition, survival probability decreased with later laying dates (CI(β) = 0.43 to 1.74 days), indicating that chicks born earlier in the breeding season had higher chances of survival. Given the correlation between chlorophyll-α and upwelling, we concluded that Brown Booby reproductive success in the Gulf of Panama is influenced by upwelling and that breeding in this tropical species follows seasonal pulses like those observed in polar and temperate species. [ABSTRACT FROM AUTHOR]

In the Cerrado, the sequential chaining of phenological events during the dry season is a pattern observed in many plant species. In this season, many plants completely lose their leaves, and soon after deciduous, there is an expressive production of leaf buds. In this study, we investigated the effect of irrigation and early defoliation on the triggering of leaf budding of the deciduous species Peixotoa tomentosa A.Juss. in the dry season of a seasonal environment with water restrictions. Therefore, we set up an experiment with three groups of plants: control (n = 15), irrigation treatment (n = 15), and removal treatment (n = 15), and after the complete deciduousness of the plants, we carried out phenological monitoring of the development of leaf buds in these plants. From July to August 2022, the leaf budding phenology of the 45 individuals was evaluated twice a week. To test whether there is a difference in the number of leaf buds between treatments, we built generalized linear mixed models (GLMMs). Plants in the removal treatment had a statistically higher number of leaf buds produced than the plants in the irrigation and control groups (P < 0.05). However, the control group and the irrigation treatment did not differ from each other (P > 0.05). We showed that early defoliation influenced the triggering of leaf buds in P. tomentosa, increasing the production of young leaves in their individuals in a seasonal environment with water restrictions. Irrigation was not able to break the dormancy of leaf buds. Our findings contribute to a better understanding of the triggering of vegetative phenophases in deciduous Cerrado plants, showing that leaf fall may play a more important role than rain in the production of leaf buds in the dry season. [ABSTRACT FROM AUTHOR]

Climate change alters many aspects of weed performance and may also alter the effectiveness of management practices to control pests. Despite this concern, entire categories of widely used management practices, such as physical control, remain understudied in this context. We conducted a field experiment growing the invasive pest musk thistle (Carduus nutans) at ambient and experimentally elevated temperatures. We tested mowing management strategies that varied in the timing of a single mowing event relative to thistles' stem elongation phenology and compared these with an unmowed control. Results from this experiment informed demographic models to project population growth rates for different warming/mowing scenarios. Compared to plants grown under ambient conditions, warmed thistles were more likely to survive the same mowing treatment, flowered earlier in the season, grew to taller heights, and produced more flowering capitula. Proportional reductions in plant height and capitulum production caused by mowing were smaller under warming. Warming did not change the relative ranking of mowing treatments; mowing late in the growing season (2 weeks after individuals first reached a height of 40 cm) was most effective at ambient temperatures and under warming. Warming caused significant increases in projected local population growth rate for all mowing treatments. For invasive musk thistle, warmed individuals outperformed individuals grown at ambient temperatures across all the mowing treatments we considered. Our results suggest that to achieve outcomes comparable to those attainable at today's temperatures, farmers will need to apply supplemental management, possibly including additional mowing effort or alternative practices such as chemical control. We recommend that scientists test management practices under experimental warming, where possible, and that managers monitor ongoing management to identify changes in effectiveness. Information about changes in managed weeds' mortality, fecundity, and phenology can then be used to make informed decisions in future climates. [ABSTRACT FROM AUTHOR]

Climate change is widely known to affect plant phenology, but little is known about how these impacts manifest in the widespread sagebrush ecosystem of the Western United States, which supports a number of wildlife species of concern. Shifts in plant phenology can trigger consequences for the plants themselves as well as the communities of consumers that depend upon them. We assembled historical observations of first‐flowering dates for 51 species collected in the 1970s and 1980s in a montane sagebrush community in the Greater Yellowstone Ecosystem and compared these to contemporary phenological observations targeting the same species and locations (2016–2019). We also assembled regional climate data (average spring temperature, day of spring snowmelt, and growing degree days) and tested the relationship between first‐flowering time and these variables for each species. We observed the largest change in phenology in early‐spring flowers, which, as a group, bloomed on average 17 days earlier, and as much as 36 days earlier, in the contemporary data set. Mid‐summer flowers bloomed on average 10 days earlier, nonnative species 15 days earlier, and berry‐producing shrubs 5 days earlier, while late summer flowering plants did not shift. The greatest correlates of early‐spring and mid‐summer flowering were average spring temperature and day of snowmelt, which was 21 days earlier, on average, in 2016–2019 relative to the 1973–1978 observations. The shifts in flowering phenology that we observed could indicate developing asynchronies or novel synchronies of these plant resources and wildlife species of conservation concern, including Greater Sage‐grouse, whose nesting success is tied to availability of spring forbs; grizzly bears, which rely heavily on berries for their fall diet; and pollinators. This underscores the importance of maintaining a diverse portfolio of native plants in terms of species composition, genetics, phenological responsiveness to climatic cues, and ecological importance to key wildlife and pollinator species. Redundancy within ecological niches may also be important considering that species roles in the community may shift as climate change affects them differently. These considerations are particularly relevant to restoration and habitat‐enhancement projects in sagebrush communities across western North America. [ABSTRACT FROM AUTHOR]

Global temperatures are generally increasing, and this is leading to a well documented advancement and extension of seasonal activity of many pest insects. Effects of changing precipitation have received less attention, but might be complex because rain and snow are increasing in some places but decreasing in others. This raises the possibility that altered precipitation could accentuate, or even reverse, the effects of rising temperatures on pest outbreaks. We used >592 K aphid suction‐trap captures over 15 years, in the heavily farmed central USA, to examine how the activity of Aphis glycines (soybean aphid), Rhopalosiphum maidis (corn aphid), and Rhopalosiphum padi (bird cherry‐oat aphid) changed with variation in both temperature and precipitation. Increasing precipitation caused late‐season flight activity of A. glycines and early‐season activity of R. padi to shift earlier, while increasing temperature did the same for early‐season activity of A. glycines and R. maidis. In these cases, precipitation and temperature exhibited directionally similar, but independent, effects. However, precipitation sometimes mediated temperature effects in complex ways. At relatively low temperatures, greater precipitation generally caused late‐season flights of R. maidis to occur earlier. However, this pattern was reversed at higher temperatures with precipitation delaying late‐season activity. In contrast, greater precipitation delayed peak flights of R. padi at lower temperatures, but caused them to occur earlier at higher temperatures. So, in these two cases the interactive effects of precipitation on temperature were mirror images of one another. When projecting future aphid flight phenology, models that excluded precipitation covariates consistently underpredicted the degree of phenological advance for A. glycines and R. padi, and underpredicted the degree of phenological delay for R. maidis under expected future climates. Overall, we found broad evidence that changing patterns of aphid flight phenology could only be understood by considering both temperature and precipitation changes. In our study region, temperature and precipitation are expected to increase in tandem, but these correlations will be reversed elsewhere. This reinforces the need to include both main and interactive effects of precipitation and temperature when seeking to accurately predict how pest pressure will change with a changing climate. [ABSTRACT FROM AUTHOR]

The main goal of this study was to describe in detail the structure and phenology of flocks of the Common Linnet (Linaria cannabina) passing through eastern Spain. Data were compiled during the spring and autumn migrations of 2019 to 2021 (excluding spring 2020), by counting and by capture for ringing. We counted 6151 flocks, comprising 17 732 birds, of which 7638 individuals were captured. The size of flocks ranged from 1 to 30 Linnets (mean ± 95% CI, 2.8 ± 0.1), with a higher proportion of solitary migrants in spring (46.8%) than in autumn (33.8%). Passage in spring peaked during the third hour after dawn, whilst in autumn this peak was just after dawn. There were more females than males (56%), probably as an indicator of latitudinal differential migration. Juveniles were significantly more abundant (c. 80%) than adults. The phenological pattern of the passage was more variable in spring than in autumn, and such variation could be useful to explore potential impacts of climate change on the migration ecology of the species. [ABSTRACT FROM AUTHOR]

• Vulnerability of Mediterranean high mountains. • Importance of monitoring early warning indicator species. • Impact of climatic fluctuations on Arenaria nevadensis. • Climatic stochasticity resulting in changing population trends in the species. • Importance of Arenaria nevadensis as indicator species; conservation strategies and knowledge gaps. Mountain ecosystems are proving to be particularly vulnerable to the effects of global change, with Mediterranean high mountains standing out as among the most susceptible regions worldwide. The impact of climate change on biota operates across key levels: metabolism, phenology, evolution, and spatial distribution. Monitoring species within these ecosystems is crucial to establish early warning indicators for effective mitigation and adaptation strategies. Within this context, annual plants, like the critically endangered species Arenaria nevadensis endemic to Sierra Nevada, could offer advantages as indicators due to their rapid life cycles and dependence on water sources. This study aims to investigate the impact of climatic change on this specific annual, endemic, and threatened species while assessing its potential as an indicator for shifting snow patterns affecting alpine biota. Analyzing data collected between 2005 and 2021 from four populations of Arenaria nevadensis alongside hydro-meteorological data revealed notable variations in population parameters linked to climatic fluctuations. Factors such as precipitation and snowpack significantly influenced plant size, reproductive potential, and population size, with neighboring populations showing distinct responses to climatic variations. The observed unpredictability in population trends across consecutive years underscores the climatic stochasticity inherent in Mediterranean mountains, particularly Sierra Nevada. Forecasts of decreased precipitation and increased temperatures are expected to diminish snowpack depth and duration, posing a severe threat to this critically endangered species. Conservation efforts should prioritize managing higher elevation populations and exploring new suitable habitats for restoration or assisted migration. While Arenaria nevadensis demonstrates promise as a climate change indicator owing to its short life cycle, restricted distribution, and sensitivity to climatic shifts, comprehensive understanding of its germination ecology, seed bank role, and reproductive biology remains lacking. Addressing these knowledge gaps is crucial to enhance its effectiveness as an indicator species. [ABSTRACT FROM AUTHOR]

Heterogeneous vegetation supports higher species richness than homogenous vegetation, which is why efficiently identifying heterogenous vegetation can be useful for biodiversity conservation. Satellite remote-sensing data provide an opportunity to generate vegetation heterogeneity metrics and to explore the phenology of vegetation patterns. Phenoclusters are vegetation types with similar phenological characteristics, and valuable for capturing vegetation habitat heterogeneity patterns. Our goal was to map phenoclusters for Wisconsin, USA, at 10-m spatial resolution based on land surface phenology metrics from EVI (Enhanced Vegetation Index) Sentinel-2 data. We characterized each phenocluster based on landcover composition and structure, phenology timing, and environmental factors, and compared them to bird species richness. We also calculated the diversity of phenoclusters at multiple spatial extents. We identified 14 phenoclusters in Wisconsin, each with distinct landcover composition and structure, and unique phenological characteristics. Our remotely-sensed phenoclusters effectively captured environmental gradients, with elevation and temperature emerging as the most important driving variables. Furthermore, the phenoclusters successfully captured bird biodiversity patterns, especially richness of forest and grassland specialist. Our results identified phenological patterns among Wisconsin's forests, shrublands, and grasslands, capturing phenological timing both among and within the same tree species. Phenoclusters are a valuable tool for capturing vegetation habitat heterogeneity, phenology diversity and biodiversity patterns, as well as climate change effects. • We mapped Wisconsin's phenoclusters at 10-m spatial resolution • We also mapped the diversity of phenoclusters at multiple spatial extents • Phenoclusters capture habitat heterogeneity and phenological patterns • Phenoclusters characterize phenology among and within species • Phenoclusters are valuable tools for biodiversity applications [ABSTRACT FROM AUTHOR]

A wide variety of organisms use the regular seasonal changes in photoperiod as a cue to align their life cycles with favorable conditions. Yet the phenological consequences of photoperiodism for organisms exposed to new climates are often overlooked. We present a conceptual approach and phenology model that maps voltinism (generations per year) and the degree of phenological mismatch that can arise when organisms with a short‐day diapause response are introduced to new regions or are otherwise exposed to new climates. Our degree‐day‐based model combines continent‐wide spatialized daily climate data, calculated date‐specific and latitude‐specific day lengths, and experimentally determined developmental responses to both photoperiod and temperature. Using the case of the knotweed psyllid Aphalara itadori, a new biological control agent being introduced from Japan to North America and Europe to control an invasive weed, we show how incorporating a short‐day diapause response will result in geographic patterns of attempted voltinism that are strikingly different from the potential number of generations based on degree‐days alone. The difference between the attempted and potential generations represents a quantitative measure of phenological mismatch between diapause timing and the end of the growing season. We conclude that insects moved from lower to higher latitudes (or to cooler climates) will tend to diapause too late, potentially resulting in high mortality from inclement weather, and those moved from higher to lower latitude (to warmer climates) may be prone to diapausing too early, therefore not fully exploiting the growing season and/or suffering from insufficient reserves for the longer duration in diapause. Mapped output reveals a central region with good phenology match that shifts north or south depending on the geographic source of the insect and its corresponding critical photoperiod for diapause. These results have direct relevance for efforts to establish populations of classical biocontrol agents. More generally, our approach and model could be applied to a wide variety of photoperiod‐ and temperature‐sensitive organisms that are exposed to changes in climate, including resident and invasive agricultural pests and species of conservation concern. [ABSTRACT FROM AUTHOR]

Forest biodiversity conservation and species distribution modeling greatly benefit from broad‐scale forest maps depicting tree species or forest types rather than just presence and absence of forest, or coarse classifications. Ideally, such maps would stem from satellite image classification based on abundant field data for both model training and accuracy assessments, but such field data do not exist in many parts of the globe. However, different forest types and tree species differ in their vegetation phenology, offering an opportunity to map and characterize forests based on the seasonal dynamic of vegetation indices and auxiliary data. Our goal was to map and characterize forests based on both land surface phenology and climate patterns, defined here as forest phenoclusters. We applied our methodology in Argentina (2.8 million km2), which has a wide variety of forests, from rainforests to cold‐temperate forests. We calculated phenology measures after fitting a harmonic curve of the enhanced vegetation index (EVI) time series derived from 30‐m Sentinel 2 and Landsat 8 data from 2018–2019. For climate, we calculated land surface temperature (LST) from Band 10 of the thermal infrared sensor (TIRS) of Landsat 8, and precipitation from Worldclim (BIO12). We performed stratified X‐means cluster classifications followed by hierarchical clustering. The resulting clusters separated well into 54 forest phenoclusters with unique combinations of vegetation phenology and climate characteristics. The EVI 90th percentile was more important than our climate and other phenology measures in providing separability among different forest phenoclusters. Our results highlight the potential of combining remotely sensed phenology measures and climate data to improve broad‐scale forest mapping for different management and conservation goals, capturing functional rather than structural or compositional characteristics between and within tree species. Our approach results in classifications that go beyond simple forest–nonforest in areas where the lack of detailed ecological field data precludes tree species–level classifications, yet conservation needs are high. Our map of forest phenoclusters is a valuable tool for the assessment of natural resources, and the management of the environment at scales relevant for conservation actions. [ABSTRACT FROM AUTHOR]

The ongoing wide‐scale introduction of nonnative plants across the world may negatively influence native invertebrate fauna, due to a lack of coevolved traits related to the novel plants, e.g., unique phytochemicals or shifted phenology. Nonnative plants, specifically trees, are common in urban environments, areas that already pose novel habitats to plants and wildlife through a wide array of anthropogenic factors. For example, impervious surfaces contribute to increased ambient temperatures, the so‐called urban heat island effect (UHI), which can affect local plant phenology. Yet, few studies have simultaneously studied the effects of urbanization and tree species origin on urban invertebrate communities. We measured the city‐level UHI and phenology of nine native and seven nonnative tree species in five city‐center parks in southern Sweden, as well as four common native species in a rural control forest. We quantified the abundance of invertebrates on a subset of native and nonnative tree species through shake sampling, sticky traps, and frass collection. In the urban environment, nonnative trees hosted significantly fewer invertebrates compared to native trees. Furthermore, the nonnative trees had a delayed phenology compared to native species, while the peak of caterpillars associated with the subset of trees surveyed for this measure was significantly earlier compared to that of the native species studied. The effect of tree species origin on urban invertebrate abundance was of a greater magnitude (effect size) than the effect of urbanization on invertebrate abundance in native tree hosts. Hence, the results indicate that the impact of nonnative vegetation may be a stronger driver of invertebrate declines in urban areas than other factors. As the effect of species origin on tree phenology was at a level comparable to the urban effect, increasing prevalence of nonnative vegetation can potentially obscure effects of urbanization on phenology in large‐scale studies, as well as induce mismatches to invertebrate populations. Since parks harbor a large proportion of urban biodiversity, native trees play a crucial role in such habitats and should not be considered replaceable by nonnative species in terms of conservation value. [ABSTRACT FROM AUTHOR]

The goal of this study was to see how a combination of Rhizobium inoculant, S, and Zn nutrients affected chickpea nodulation and yield (Cicer arientinum L.) at Gewane, northeastern Ethiopia. The experiment included 12 treatments arranged in factorial combination of levels of inoculation (Rhizobium inoculated, un-inoculated), three rates of S (0, 15, 30 kg Sulphur ha-1) and rates of Zn (0, 1.5 kg Zinc ha-1). The treatment becomes laid out in randomized complete block design with 3 replications. Analysis of variance showed that yield and yield associated parameters (main branches, number of pod, quantity of seed, hundred seed weight, grain and straw yield), crop phenology (days to 50% flowering and days to physiological maturity), nodulation scores (nodule amount, nodule volume, nodule dry weight, effective nodule and nodulation score), N and P uptake at both locations had been significantly affected by the treatments. The best (1775.5 kg ha-1) suggest rate of seed yield over locations changed into acquired from blended costs of rhizobium and 30 kg S ha-1 which led to 28 % (389 kg ha-1) growth over the control. Consequently, rhizobium inoculation with rate of 30 kg S ha-1is recommended for chickpea production on the experimental site. [ABSTRACT FROM AUTHOR]

Copyright of Ecosistemas y Recursos Agropecuarios is the property of Universidad Juarez Autonoma de Tabasco 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.)

Copyright of Brazilian Journal of Biology is the property of Instituto Internacional de Ecologia 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.)

Copyright of Brazilian Journal of Biology is the property of Instituto Internacional de Ecologia 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.)

The differences between the phenology of plants in rural and urban areas are the subject of research all over the world. The aim of this study is to assess the impact of urban conditions and distance from the town center on the phenology of ornamental species: Forsythia x intermedia; Mahonia aquifolium; Spiraea x vanhouttei; Albizia julibrissin; Syringa vulgaris; Chaenomeles japonica, Aesculus hippocastanum; Prunus cerasifera; Catalpa bignonioides; Tilia tomentosa. The study assesed the date of average onset of individual phenological phases of some ornamental species, analyzing the variability of dates when bud-bursting, flowering and fruit-setting occur, in relation to the two areas analyzed, namely the town center and a neighboring area located 5 km from the town center. In order to compare the bud-bursting (09 BBCH), the first open flowers (60 BBCH), the end of flowering (69 BBCH) and the ripe fruit (89 BBCH), the F-Test Two - Sample for Variances test was used. The results show the variation of phenological phases from one species to another, from one area to another and the influence of urban environment on phenology, on vegetation season of the analyzed species, each phenological phase starting earlier in the town center compared to the neighboring area, 5 km away. [ABSTRACT FROM AUTHOR]

Unseasonal fire occurrence is increasing globally, driven by climate change and other human activity. Changed timing of fire can inhibit postfire seedling recruitment through interactions with plant phenology (the timing of key processes, e.g., flower initiation, seed production, dispersal, germination), and therefore threaten the persistence of many plant species. Although empirical evidence from winter‐rainfall ecosystems shows that optimal seedling recruitment is expected following summer and autumn (dry season) fires, we sought experimental evidence isolating the mechanisms of poor recruitment following unseasonal (wet season) fire. We implemented a seed‐sowing experiment using nine species native to fire‐prone, Mediterranean‐climate woodlands in southwestern Australia to emulate the timing of postfire recruitment and test key mechanisms of fire seasonality effects. For seeds sown during months when fire is unseasonal (i.e., August–September: end of the wet winter season), seedling recruitment was reduced by up to 99% relative to seeds sown during seasonal fire months (i.e., May–June: end of the dry summer season) because of varying seed persistence, seedling emergence, and seedling survival. We found that up to 70 times more seedlings emerged when seeds were sown during seasonal fire months compared to when seeds were sown during unseasonal fire months. The few seedlings that emerged from unseasonal sowings all died with the onset of the dry season. Of the seeds that failed to germinate from unseasonal sowings, only 2% survived exposure on the soil surface over the ensuing hot and dry summer. Our experimental results demonstrate the potential for unseasonal fire to inhibit seedling recruitment via impacts on pregermination seed persistence and seedling establishment. As ongoing climate change lengthens fire seasons (i.e., unseasonal wildfires become more common) and managed fires are implemented further outside historically typical fire seasons, postfire seedling recruitment may become more vulnerable to failure, causing shifts in plant community composition towards those with fewer species solely dependent on seeds for regeneration. [ABSTRACT FROM AUTHOR]

Copyright of Biotechnologie, Agronomie, Societe et Environnement is the property of Les Presses Agronomiques de Gembloux 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.)

An early crop classification method is functionally required in a near-real-time crop-yield prediction system, especially for upland crops. This study proposes methods to estimate the mixed-pixel ratio of corn, soybean, and other classes within a low-resolution MODIS pixel by coupling MODIS-derived crop phenology information and the past Cropland Data Layer in a random-forest regression algorithm. Verification of the classification accuracy was conducted for the Midwestern United States. The following conclusions are drawn: The use of the random-forest algorithm is effective in estimating the mixed-pixel ratio, which leads to stable classification accuracy; the fusion of historical data and MODIS-derived crop phenology information provides much better crop classification accuracy than when these are used individually; and the input of a longer MODIS data period can improve classification accuracy, especially after day of year 279, because of improved estimation accuracy for the soybean emergence date. [ABSTRACT FROM AUTHOR]

Monitoring seabirds and their responses to ecosystem change provides essential information for understanding the reasons behind any changes in productivity or populations. However, many species nest in remote locations, which poses logistical challenges for long-term studies. Remote cameras offer an opportunity to confront this issue. The Black-legged Kittiwake Rissa tridactyla (kittiwake) has been used as an indicator of changes in its environment and is a prime candidate for monitoring via remote cameras. To investigate the potential for camera application, we used a remote camera system to collect six years (2010-2015) of reproductive data from a sub-colony of kittiwakes in Resurrection Bay near Seward, Alaska, USA. Our objective was to identify factors influencing the reproductive success of kittiwakes at our study location by 1) establishing the reproductive phenology and estimates of productivity, 2) determining the effect of physical nest-site characteristics and locations on individual nest success, and 3) identifying the effect of seasonal weather patterns on nest, egg, and chick loss events. We found a significant positive correlation between nest success and both nest height from mean high tide level and nest location on island vs. mainland habitat. Nest loss was positively correlated with wind speed; egg loss was negatively correlated with wind speed; and chick loss was uncorrelated with measured weather conditions, including rainfall and air temperature. Remote camera technology proved to be a useful tool in monitoring and identifying factors influencing nesting parameters in this cliff-nesting seabird. [ABSTRACT FROM AUTHOR]

Tree growth is the most important factor in determining the carbon sequestration processes of forest ecosystems. However, the growth phenology (seasonal growth pattern) and responses of tree growth to climatic variables vary considerably among different species, especially between deciduous and evergreen species. Thus, it is crucial to explore the seasonal growth patterns of different tree species in relation to climate to better understand the responses of tree physiology to climate changes, especially in mixed-species forest stands. In this study, we monitored the daily basal area increments of 220 individuals belonging to 15 common broadleaved tree species, nine deciduous and six evergreen species, in mixed-species experimental stands in subtropical China and analysed the relationships between radial stem growth and seasonal climate at a high-temporal resolution. We fitted daily increments of stem diameters with four frequently used nonlinear models and chose the best model for each species. The results showed that the evergreen trees grew faster than the deciduous trees, both annually and within the growing season. The tested nonlinear models (Korf, Weibull, logistic and Gompertz) produced good fits for the growth patterns of all species. Overall, the evergreen species began stem growth earlier and finished later during the growing season than that of the deciduous species. Within the growing season, the radial growth of trees in mixed stands containing both types of species was strongly positively correlated with humidity. In spring, increases in both temperature and moisture increased the daily relative basal area increment of all species. Maximum growth rates occurred when the soil water content reached its highest level and gradually decreased when the soil water content decreased. In summer, high temperatures combined with low amounts of precipitation led to heat-induced summer drought, to which the evergreen trees appeared to be more tolerant than the deciduous trees, which was reflected in the reduced stem growth of the latter. These results indicate the different climate-dependent seasonal growth strategies of evergreen and deciduous trees related to the trade-off described by the leaf economics spectrum, i.e., short-lived leaves with higher assimilation rates in deciduous and longer-lived leaves with a greater drought tolerance in evergreen species. [ABSTRACT FROM AUTHOR]

Many organisms respond to anthropogenic environmental change through shifts in their phenology. In plants, flowering is largely driven by temperature, and therefore affected by climate change. However, on smaller scales climatic conditions are also influenced by other factors, including habitat structure. A group of plants with a particularly distinct phenology are the understory herbs in temperate European forests. In these forests, management alters tree species composition (often replacing deciduous with coniferous species) and homogenizes stand structure, and as a consequence changes light conditions and microclimate. Forest management should thus also affect the phenology of understory herbs. To test this, we recorded the flowering phenology of 16 early‐flowering herbs on 100 forest plots varying in management intensity, from near‐natural to intensely managed forests, in central and southern Germany. We found that in forest stands with a high management intensity, such as Norway spruce plantations, the plants flowered on average about 2 weeks later than in unmanaged forests. This was largely because management also affected microclimate (e.g., spring temperatures of 5.9°C in managed coniferous, 6.7 in managed deciduous, and 7.0°C in unmanaged deciduous plots), which in turn affected phenology, with plants flowering later on colder and moister forest stands (+4.5 d per −1°C and 2.7 d per 10% humidity increase). Among forest characteristics, the percentage of conifers had the greatest influence on microclimate, but also the age, overall crown projection area, structural complexity and spatial distribution of the forest stands. Our study indicates that forest management alters plant phenology, with potential far‐reaching consequences for the ecology and evolution of understorey communities. More generally, our study demonstrates that besides climate change other drivers of environmental change, too, can influence the phenology of organisms. [ABSTRACT FROM AUTHOR]

Tracking phenological change in a regionally explicit context is a key to understanding ecosystem status and change. The current study investigated long‐term trends of satellite‐observed land surface phenology (LSP) in the 17 National Ecological Observatory Network (NEON) domains across the conterminous United States (CONUS). Characterization of LSP trends was based on a high temporal resolution (3‐d) time series of the two‐band enhanced vegetation index (EVI2) derived from a long‐term data record (LTDR) of the Advanced Very High Resolution Radiometer (AVHRR) and the Moderate Resolution Imaging Spectroradiometer (MODIS). We identified significant trend patterns in LSP and their seasonal climate and land use/land cover drivers for each NEON domain. Key findings include (1) the start of season (SOS) predominantly shifted later in 13 out of 17 domains (24.3% of CONUS by area) due potentially to both a lack of spring warming in the eastern United States and changes in agronomic practices over agricultural lands; (2) the end of season (EOS) became predominantly later in nine domains dominated by natural vegetation (14.1% of CONUS by area) in response to widespread warming in autumn; (3) the EOS predominantly shifted earlier in three domains (10.6% of CONUS by area) over primarily agricultural lands as potentially affected by changes in crop growth cycles; and (4) earlier shift in the SOS was mostly found in the Northwest (3.6% of CONUS by area) and was predominant only in the moist Pacific Northwest (27.7% of the domain by area) in response to more pronounced spring warming in the region. The overall patterns of SOS and EOS trends across CONUS appeared constrained by continental‐scale temperature trends as characterized by a west‐east dipole and the distribution of the nation's agricultural lands. In addition, seasonal trend analysis revealed that most NEON domains (15/17) became predominantly greener in part of or throughout the growing season, potentially contributed by both climate change‐induced growth increase and improved agricultural productivity. The domain‐wide LSP trends with their underlying drivers identified here provide important contextual information for NEON science as well as for investigations within CONUS using other distributed observatories (e.g., LTER, LTAR, FLUXNET, USA‐NPN, etc.). [ABSTRACT FROM AUTHOR]

For ungulates and other long‐lived species, life‐history theory predicts that nutritional reserves are allocated to reproduction in a state‐dependent manner because survival is highly conserved. Further, as per capita food abundance and nutritional reserves decline (i.e., density dependence intensifies), reproduction and recruitment become increasingly sensitive to weather. Thus, the degree to which weather influences vital rates should be associated with proximity to nutritional carrying capacity—a notion that we refer to as the Nutritional Buffer Hypothesis. We tested the Nutritional Buffer Hypothesis using six moose (Alces alces) populations that varied in calf recruitment (33–69 calves/100 cows). We predicted that populations with high calf recruitment were nutritionally buffered against the effects of unfavorable weather, and thus were below nutritional carrying capacity. We applied a suite of tools to quantify habitat and nutritional condition of each population and found that increased browse condition, forage quality, and body fat were associated with increased pregnancy and calf recruitment, thereby providing multiple lines of evidence that declines in calf recruitment were underpinned by resource limitation. From 2001 to 2015, recruitment was more sensitive to interannual variation in weather (e.g., winter severity, drought) and plant phenology (e.g., duration of spring) for populations with reduced browse condition, forage quality, and body fat, suggesting these populations lacked the nutritional reserves necessary to buffer demographic performance against the effects of unfavorable weather. Further, average within‐population calf recruitment was determined by regional climatic variation, suggesting that the pattern of reduced recruitment near the southern range boundary of moose stems from an interaction between climate and resource limitation. When coupled with information on habitat, nutrition, weather, and climate, life‐history theory provides a framework to estimate nutritional limitation, proximity to nutritional carrying capacity, and impacts of climate change for ungulates. [ABSTRACT FROM AUTHOR]

Knowledge of the ecology of the Eastern Black Rail (Laterallus jamaicensis jamaicensis) has remained nearly as elusive as the rail itself. Camera trapping methods facilitated the first study of breeding phenology and chick development, courtship and brood rearing behaviors, and flightless molt phenology and duration. Broods (n = 33) were observed between August 2015 - September 2019. Chicks were capable of flight at approximately 40 days after hatching. Nesting was initiated as early as 17 April 2019 (x̄ = 5 June ± 30.0 SD) and fledging occurred as late as 30 September 2019 (x̄ = 10 August). Behavioral observations combined with phenology data provided evidence of pairs raising two or more broods during a breeding season. Flightless molt (n = 10 adults in molt), which was initiated as early as 15 August 2019 and completed as late as 11 October 2019, was completed within approximately 21 days of initiation. Conservation and management strategies should take into consideration periods of vulnerability, which coincide with increasingly severe and frequent coastal flooding events and hurricanes. It is necessary to understand factors key to fecundity and survival to effectively develop conservation strategies to ensure the persistence of the subspecies. [ABSTRACT FROM AUTHOR]

Short-tailed fruit bats typically breed twice a year, fitting a seasonal bimodal polyestry pattern in many ecosystems along their distributional range. For two species, Carollia perspicillata and C. benkeithi, reproductive timing was studied on a monthly basis and related to environmental seasonality (climatic factors and fruit resource availability) in a Peruvian premontane forest with a secondary succession plant composition. Sex, age and reproductive condition were assessed through morphological inspection. Plant species, whose fruits were known to be consumed by these bats, were scored for fruit resource availability. For C. perspicillata, lactation followed a bimodal pattern with peaks at the onset (September–October) and the middle of the rainy season (February–March). The proportion of lactating females was positively correlated with rainfall, temperature and fruit resource availability. In contrast, reproductive males, as indicated by descended testes, occurred during the dry season and its proportion was negatively correlated with rainfall. For C. benkeithi, records of reproductive females suggest that births also occur during the rainy season. This study supports the previously suggested synchronization of births with higher fruit resource availability for Carollia species, and contributes with information about the geographic variation of their reproductive phenology. [ABSTRACT FROM AUTHOR]

Copyright of SHILAP Revista de Lepidopterologia is the property of Sociedad Hispano-Luso-Americana de Lepidopterologia 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.)

NIRvP, the product of the remotely sensed near infrared reflectance of vegetation (NIRv) and photosynthetically active radiation (PAR), has been demonstrated to be a good proxy for terrestrial gross primary productivity (GPP) due to their strong theoretical correlation. Currently, a linear relationship with a constant slope parameter (k) is used to estimate GPP with NIRvP. However, this parameter may vary with plant phenology, potentially leading to uncertainty in GPP estimation. In this study, we hypothesized that considering the influence of phenology on k could improve the accuracy of GPP estimation. To test this hypothesis, we used pair measurements of ground eddy covariance-derived GPP and satellite-derived NIRvP across nine temperate deciduous forest sites, and compared the modeling results of two parameterization schemes: one with a constant k throughout the entire growing season (termed the global scheme) and another with dynamic k parameters across different phenophases (e.g., greenup, mature and senescence phases; termed the phenophase scheme). Our results show that relative to the global scheme, the phenophase scheme significantly improved GPP estimation with a reduction in bias by 63.71 ± 16.46%, 53.71 ± 26.17% and 32.96 ± 32.07% in the greenup, maturity and senescence phases across all study sites, respectively. Moreover, the efficiency of this improvement is meaningful in terms of the Akaike Information Criterion (AIC). Further regression analysis revealed that k varies with phenophase, which can be attributed to variations in photosynthetic capacity and canopy optical properties due to leaf aging and canopy structure development. These findings collectively improve our understanding of the influence of phenology on the GPP-NIRvP relationship and emphasize the effectiveness of using the phenophase-dependent k parameterization scheme, which would ultimately contribute to improving the accuracy of GPP estimation in temperate forest ecosystems. • Seasonal relationships between GPP and satellite-based NIRvP were detected for DBFs. • The GPP-NIRvP correlations were significant but diverse during different phenophases. • The slope of the linear regression model between GPP and NIRvP varied with phenology. • The NIRvP-based model with phenology significantly improved GPP estimation accuracy. [ABSTRACT FROM AUTHOR]

Mediterranean oak-dominated agro-silvo-pastoral systems of southwestern Europe (called montado in Portugal and dehesa in Spain) are semi-natural, savannah-style High Nature Value farmlands (HNVfs) shaped by centuries of anthropogenic (e.g., cultivation, grazing) and natural (e.g., drought) disturbances. Therefore, changes in grazing and precipitation may alter their vegetation composition and ecosystem properties and impact upon their long-term viability. We quantified the responses of soil organic carbon (SOC) and plant taxonomic and functional trait diversities to cattle grazing and inter-annual changes in precipitation across three open-woodland sites within the montado landscape in Alentejo, southern Portugal. The sites are characterised by the presence or absence of cattle grazing and different amounts of mean annual precipitation (ranging from semiarid to dry subhumid). Three different precipitation periods were used: a shorter autumn-to-spring period and longer 12- and 18-month periods before sampling. Specific leaf area, plant height and seed mass were used to estimate single-trait community weighted means and a multi-trait measure of community functional diversity (Rao's Q). SOC and plant species richness responded negatively to the presence of cattle grazing but positively to increase in precipitation (and its interaction with cattle grazing), while trait-based measures were largely unresponsive to cattle grazing and precipitation (though RLQ analysis revealed strong controls of the environmental variables on plant life cycle, growth form, leaf phenology and dispersal strategies). SOC was most responsive to longer-term (18-month) changes in precipitation, whereas plant species richness was most responsive to shorter-term (autumn-to-spring) changes in precipitation. These results suggest that different components of plant diversity respond differently to external drivers in montado HNVfs, while the response time of soil properties may be longer than that of plant taxonomic diversity. • We assessed three sites in oak woodlands under different amounts of precipitation. • Taxonomic and functional diversity respond differently to grazing and precipitation. • Plant species richness is most responsive to autumn-to-spring precipitation. • Soil organic carbon is most responsive to 18-month changes in precipitation. • Soil organic carbon responds negatively to grazing but positively to precipitation. [ABSTRACT FROM AUTHOR]

Plant phenology has been and continues to be impacted by climate change. Process-oriented modeling of phenology reveals biological characteristics through interpretation of model results and parameter values. This paper aims to implement a cold hardiness model using historical Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) data, determine if model results improve with data clustering by seed source or growing location, and interpret model results into biological meaning. These interpretations have applications for reforestation and studies of plant phenological response to climate change. Cold hardiness data were compiled through literature review. A dynamic process-oriented cold hardiness model driven by thermal time based on daily temperatures was applied to multiple data clustering scenarios. Model results were analyzed for goodness of fit to determine model error, efficiency, and bias. A sensitivity analysis was performed to determine parameter sensitivity, and further validate the model calibration. Data clustering by seed source improved fit compared to clustering by growing location or no clustering, when applied to the full dataset. Using only temperature inputs, model results had low error when data modeled were similar. Results show that for cold hardiness acclimation a linear growing degree function with a threshold of 10 °C was adequate across testing data, as was an upper limit cold hardiness temperature of –3 °C. Interpretation of model results show that both acclimation to growing sites and seed source genetics impact cold hardiness response, though clustering by seed source improved model performance. This model could be applied to mitigate cold related risks to seedlings during production and establishment, and serve as a template for predicting phenological responses in simulated future climate scenarios. • Grouping by genetic factors results in improved model prediction in cold hardiness modeling of Douglas-fir. • A process oriented dynamic cold hardiness model using daily temperature as input can predict conifer cold hardiness phenology. • Parameter estimates with low variability and sensitivity are candidates for fixed values, which may also reveal biological temperature thresholds: the upper limit of cold hardiness (H c, ul) of -3 °C and the threshold temperature of acclimation (T th,a) of 10 °C. [ABSTRACT FROM AUTHOR]

Progressive global warming and decreasing freshwater resources are forcing to look for alternative solutions in plants cultivation. The use of saltwater and cultivation in saline areas becomes increasingly common. Wild strawberry is a rich source of antioxidant compounds beneficial for human health. The aim of the study was to investigate the effect of Tytanit® on the physiological activity of wild strawberry grown under different salinity levels (32.5, 50 and 100 mM L-1 NaCl). Assimilatory pigments content, free proline concentration, chlorophyll fluorescence and relative water content were measured at two phenological phases BBCH 15 and 60. Results analysis revealed that the applicability of Tytanit® to mitigate physiological stress in wild strawberry caused by salinity did not produce the desired effect. [ABSTRACT FROM AUTHOR]

While more and more studies are exploring the application of remote sensing in assessing biodiversity for different ecosystems, most consider biodiversity at one point in time. Using several remote‐sensing‐based metrics, we asked how well remote sensing can detect biodiversity (both α‐ and β‐diversity) in a prairie grassland across time using airborne hyperspectral data collected in two successive years (2017 and 2018) and at different periods in the growing season (2018). The ability to detect biodiversity using "spectral diversity" and "spectral species" types indeed varied significantly over a 2‐yr timespan. Toward the end of the growing season in 2018, the relationship between field‐ and remote‐sensing‐based α‐ and β‐diversity weakened compared to data collected from the same season in the previous year. This contrasting pattern between the two years was likely influenced by prescribed fire, altered weather, and the resulting shifting species composition and phenology. These findings indicate that direct detection of α‐ and β‐diversity in grasslands should be multi‐temporal when possible and should consider the effect of disturbances, climate variables, and phenology. We demonstrate an essential role for airborne platforms in developing a global biodiversity monitoring system involving forthcoming space‐borne hyperspectral sensors. [ABSTRACT FROM AUTHOR]

Manx Shearwaters are transequatorial migrants, and most of the world's population breeds in Britain and winters off the Patagonian Shelf in the western South Atlantic. The migration route of British birds follows a well-known clockwise movement between the North and South Atlantic, taking advantage of the winds. Whether this main Manx Shearwater migration corridor is used by the smaller populations breeding in the western North Atlantic is unknown. Here, we report our findings from tracking two adults from a newly-established colony of Manx Shearwaters in Maine, USA using miniature geolocators. The tracked shearwaters followed a post-breeding migration route southward along the US East Coast, through the Caribbean Sea, and along the coast of eastern South America. Such a route greatly differs from the western North Atlantic birds' southbound migration route, being instead the reverse of the British birds' spring migration route. We also used the tracking data to provide insight into the phenology of the birds' annual cycle. Although our sample size is very small, our findings reveal a previously unknown migration route of Manx Shearwaters and raise questions about the origin of birds on western North Atlantic colonies and the mechanisms controlling migratory direction in the species. [ABSTRACT FROM AUTHOR]

Copyright of Revista de la Academia Colombiana de Ciencias Exactas, Físicas y Naturales is the property of Academia Colombiana de Ciencias Exactas, Fisicas y Naturales 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.)