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Copyright of Western North American Naturalist is the property of Monte L. Bean Life Science Museum 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.)

Neuro-symbolic models combine deep learning and symbolic reasoning to produce better-performing hybrids. Not only do neuro-symbolic models perform better, but they also deal better with data scarcity, enable the direct incorporation of high-level domain knowledge, and are more explainable. However, these benefits come at the cost of increased complexity, which may deter the uninitiated from using these models. In this work, we present a framework to simplify the creation of neuro-symbolic models for tree crown delineation and tree species classification via the use of object-oriented programming and hyperparameter tuning algorithms. We show that models created using our framework outperform their non-neuro-symbolic counterparts by as much as two F1 points for crown delineation and three F1 points for species classification. Furthermore, our use of hyperparameter tuning algorithms allows users to experiment with multiple formulations of domain knowledge without the burden of manual tuning. [ABSTRACT FROM AUTHOR]

The effective characterization of landscape water balance components—evapotranspiration, runoff, recharge, and soil storage—is critical for understanding the integrated effects of the water balance on vegetation dynamics, water availability, and associated environmental responses to climate change. An improved parameterization of these components can improve assessments of landscape stress and provide useful insights for predicting and managing vegetation responses to climate change. Hydrology models typically are not able to address water availability below the mapped soil profile, but we refined a landscape hydrology model, the Basin Characterization Model, by balancing measures of actual evapotranspiration (AET) with modeled subsurface soil water holding capacity, including bedrock storage. The purpose of this study was to characterize the effective rooting depth (the depth of soil and bedrock storage required to support AET) for 35 native vegetation types in California in order to quantify soil and bedrock water use, which ranged from 0 to 3.1 m for most vegetation types, exceeding mapped soil depths. This resulted in the quantification of bedrock water use, increasing available water 67% over that calculated by mapped soils alone. We found that mid-elevation vegetation types with lower water and energy limitations have the highest evapotranspiration rates and deepest effective rooting depth. We also evaluated the resilience to drought with this more spatially realistic characterization of water and vegetation interactions. [ABSTRACT FROM AUTHOR]

Shiyan Reservoir is situated in a densely populated urban area in Shenzhen, China, where its water quality and ecological health are crucial for the safety and security of the city's drinking water supply. To assess these factors, 13 water quality and ecological indicators were monitored over a 14-month period. Chlorophyll-a concentrations in Shiyan Reservoir ranged from 21.25 to 88.77 µg/L, with pronounced temporal heterogeneity and substantial variation. The highest chlorophyll-a levels, averaging around 85 µg/L, were recorded from April to July, indicating a high risk of algal blooms during this period. The reservoir's annual average water temperature (WT) was 25.31°C, with temperatures rising to approximately 30°C from May to September, further increasing bloom risk. Chemical oxygen demand (COD) ranged from 1.71 to 3.08 mg/L, and total organic carbon (TOC) varied from 2.22 to 5.13 mg/L, indicating minimal organic pollution that meets Class I surface water standards. However, total nitrogen (TN) pollution remains severe, with concentrations between 1.66 and 2.49 mg/L, aligning with Class V surface water standards. Although recent reductions in TN levels have been observed, it continues to be the primary pollutant in the reservoir. Total phosphorus (TP) concentrations, ranging from 0.01 to 0.043 mg/L, are sufficiently low to meet Class I-II surface water standards. The reservoir's monthly average integrated trophic state index fluctuated between 43.13 and 53.81, with an annual average of 50.49, indicating a state of light eutrophication from April to May and moderate eutrophication in other months. Correlation analyses revealed WT as the primary factor influencing phytoplankton dynamics during the flood season, with a correlation coefficient of 0.69. In the flood season, WT, TOC, nitrate nitrogen, and transparency were the main factors affecting phytoplankton growth, while in the dry season, TOC, dissolved oxygen (DO), and WT were the primary drivers. Two-way ANOVA results indicated that temporal factors and sampling location, along with their interactions, explained the variations in environmental factors, with temporal heterogeneity significantly exceeding spatial heterogeneity. Cyanobacteria dominated from May to October, while diatoms were prevalent from November to February. Correlation and canonical correspondence analyses (CCA) highlighted significant differences in the environmental drivers of cyanobacteria, diatoms, and green algae. WT was the primary influencing factor for all three algae types, while organic matter and nutrients from runoff during the pre-flood season acted as critical triggers for cyanobacterial blooms. Additionally, a negative correlation was found between the nitrogen-to-phosphorus ratio and the abundance of cyanobacteria, green algae, and diatoms, suggesting that phosphorus may be a limiting factor for algal growth in Shiyan Reservoir. [ABSTRACT FROM AUTHOR]

Aim: Shifting climates are reshaping ecosystems globally and are projected to intensify over the coming century. Understanding how biodiversity will respond to these shifts is crucial for developing effective climate adaptation measures. We generate predictive models built from long‐term data to hindcast historic fluctuations in small mammal abundances as they have responded to shifting rainfall and fire conditions. This data set serves as the basis for predicting historical variations (hindcasting) in small mammal abundances, allowing us to examine their responses to decadal changes in fire and rainfall conditions within our study landscape. Location: Australia (Victoria). Taxa: Small mammals (Mammalia). Time Period: 1970–2022. Methods: Small mammal abundance was surveyed at 36 long‐term trapping sites and modelled against coinciding fire history, vegetation productivity and rainfall using generalized additive mixed models. Six species were then used in predictive modelling against these variables for the decades preceding our monitoring programme (1970–2007). Results: All species abundances increased with higher rainfall. Time since fire was also an important variable in all but one species model, with species displaying varying responses to time since fire. Hindcasting predictions for small mammal abundances varied with some species showing marked declines over time. Clear trends emerged, indicating more volatile population fluctuations in response to intensified fire and rainfall extremes in the 21st century. This suggests that periods of higher rainfall and less frequent fire events in the decades preceding our monitoring period supported higher and more stable small mammal abundances. Conclusions: Native species show distinct sensitivity to the combined effects of drought and fire, which has occurred in recent times. Intensification of these drivers has caused increased volatility in small mammal abundances with low abundance extremes occurring more frequently. [ABSTRACT FROM AUTHOR]

Aim: Variation in spatial predictions of species' ranges made by various models has been recognized as a significant source of uncertainty for modelling species distributions. Consensus approaches that combine the results of multiple models have been employed to reduce the uncertainty introduced by different algorithms. We evaluate how estimates of habitat suitability, projected using species distribution models (SDMs), varied among different consensus methods relative to the variation introduced by different global climate models (GCMs) and representative concentration pathways (RCPs) used for projection. Location: California Floristic Province (California, US portion). Methods: We modelled the current and future potential distributions of 82 terrestrial plant species, developing model predictions under different combinations of GCMs, RCPs, time periods, dispersal assumptions and SDM consensus methods commonly used to combine different species distribution modelling algorithms. We assessed how each of these factors contributed to the variability in future predictions of species habitat suitability change and aggregate measures of proportional change in species richness. We also related variability in species‐level habitat change to species' attributes. Results: Assuming full dispersal capacity, the variability between habitat predictions made by different consensus methods was higher than the variability introduced by different RCPs and GCMs. The relationships between species' attributes and variability in future habitat predictions depended on the source of uncertainty and dispersal assumptions. However, species with small ranges or low prevalence tended to be associated with high variability in range change forecasts. Main Conclusions: Our results support exploring multiple consensus approaches when considering changes in habitat suitability outside of species' current distributions, especially when projecting species with low prevalence and small range sizes, as these species tend to be of the greatest conservation concern yet produce highly variable model outputs. Differences in vulnerability between diverging greenhouse gas concentration scenarios are most readily observed for end‐of‐century time periods and within species' currently occupied habitats (no dispersal). [ABSTRACT FROM AUTHOR]

Although the negative consequences of increased nitrogen (N) supply for plant communities and soil chemistry are well known, most studies have focused on mesic grasslands, and the fate of added N in arid and semi-arid ecosystems remains unclear. To study the impacts of long-term increased N deposition on ecosystem N pools, we sampled a 26-year-long fertilization (10 g N m -2 yr -1) experiment in the northern Chihuahuan Desert at the Sevilleta National Wildlife Refuge (SNWR) in New Mexico. To determine the fate of the added N, we measured multiple soil, microbial, and plant N pools in shallow soils at three time points across the 2020 growing season. We found small but significant increases with fertilization in soil-available NO 3- -N and NH 4+ -N, yet the soil microbial and plant communities do not appear to be taking advantage of the increased N availability, with no changes in biomass or N content in either community. However, there were increases in total soil N with fertilization, suggesting increases in microbial or plant N earlier in the experiment. Ultimately, the majority of the N added in this multi-decadal experiment was not found in the shallow soil or the microbial or plant community and is likely to have been lost from the ecosystem entirely. [ABSTRACT FROM AUTHOR]

To quickly and accurately obtain the moisture status of grape plants at the field scale, the treatments included three irrigation levels i.e. W3 (100%M, M as the irrigation quota), W2 (75% M) and W1 (50%M) and four fertilizer application rates i.e. F0 (0 kg/hm2), F1 (324 kg/hm2), F2 (486 kg/hm2) and F3 (648 kg/hm2). Grape leaf water content (LWC) was monitored nondestructively by an unmanned aerial vehicle (UAV) carrying multispectral (MS), visible light (RGB) and thermal infrared (TIR) cameras to extract band reflectance (BR), canopy coverage (CC) and canopy temperature (T) information, respectively. Using BR (included six bands: B, R, G, RE, NIR800, and NIR900), CC and T and their combinations as input variables brought into the partial least squares (PLS), random forest (RF), support vector machine (SVM) and extreme learning machine (ELM) algorithms. The prediction models for grape LWC were established by using four machine learning algorithms, and the optimal combination of variables was finally determined. The results represented that (1) the model built with BR + CC + T as predictor variables under different water treatments was better than other combinations of variables, with the coefficient of determination (R2) above 0.69 and the relative root mean square error (RRMSE) less than 2.5%; (2) modeling the LWC of grapes at different fertility periods based on the combination of BR + CC + T, the R2 ranged from 0.51 to 0.78 at the shoot-growing, anthesis, and fruit-inflating stages; (3) the top three important variables were T, NIR800, and NIR900 in the shoot-growing, anthesis, and fruit-inflating stages, while the top three important variables were RE, B, and T in the fruit-inflating stage. In summary, UAV multimodal data fusion has good application in predicting the LWC of grapes using RF algorithm modeling during the different growth stages. This study can supply a technical support for precise management of vineyard water regime using a UAV platform. [ABSTRACT FROM AUTHOR]

In this study, we quantify the differences in gross primary production (GPP), respiration (R), and algal nutrient limitation (nitrogen and phosphorus) in the littoral and pelagic habitats of an oligotrophic Patagonian lake (southern South America). We used submerged high frequency sensors that measure light, temperature, and dissolved oxygen and wind data to calculate GPP and R in both lake habitats. In addition, we carry out nutrient enrichment bioassays with nitrate, ammonium, and phosphate to determine which nutrient(s) limit algal growth in each lake habitat. On average, the productivity rate was 7.2 times higher at the epi-littoral (32.0 to 5.3 mmol O2 m−2 d−1) relative to the epi-pelagic (4.1 to 1.3 mmol O2 m−2 d−1). Algal growth in the littoral habitat was limited by nitrate and ammonium, while the pelagic habitat was co-limited by nitrogen (nitrate or ammonium) and phosphorus. Our work demonstrates that the littoral habitat of a Patagonian oligotrophic lake is more productive than the pelagic habitat and that the nutrients limiting algal growth in both habitats are different. These results underscore habitat variations and their significance in shaping the lake's trophic dynamics for the first time in the southern hemisphere. [ABSTRACT FROM AUTHOR]

The given document is a list of references for various scientific articles and reports related to climate change and its impact on biodiversity. The articles cover topics such as the effects of climate change on butterfly populations, the vulnerability of ecosystems to vegetation shifts, the decline of desert bird communities, and the projected range shifting of montane mammals. The references also include reports from organizations like the International Energy Agency and the Intergovernmental Panel on Climate Change. [Extracted from the article]

Increasing trends of atmospheric nitrogen (N) deposition resulting from a large number of anthropogenic emissions of reactive N are dramatically altering the global biogeochemical cycle of N. Nitrogen uptake by mosses occurs mainly from the atmosphere, making it a competent bio-indicator of N deposition. However, high uncertainties exist when using mosses to indicate N deposition, especially in choosing sampling periods and sampling frequencies. In this study, atmospheric N deposition and moss N content in the urban–agro–forest transition, a region with a high N deposition level of 27.46–43.70 kg N hm -2 yr -1 , were monitored, and the method for monitoring atmospheric N deposition by mosses was optimized. We found that the optimal sampling frequency is within 6 months per time, and the optimal sampling times are winter (January and February), autumn (October and November), and summer (July and August), which provides us with a more accurate estimation of atmospheric N deposition than other scenarios. In addition, the moss N content serves as a more reliable N species. This study eventually allowed mosses to be used more effectively and sensibly as an indicator of atmospheric N deposition and helped to improve the accuracy of the model for quantifying N deposition. [ABSTRACT FROM AUTHOR]

The accurate identification of forest degradation and its driving factors is a prerequisite for implementing high-quality forest management. However, distinguishing degradation patterns is often neglected in large-scale forest quality assessments. The indicators were constructed to identify typical forest degradation patterns using remote sensing indexes, followed by an analysis of the spatiotemporal dynamics of forest degradation and quantification of the contributions from various driving factors. The results indicated that the constructed indicators could effectively distinguish typical forest degradation patterns, with a fire degradation identification accuracy of 90.0% and a fitting accuracy of drought and pest degradation higher than 0.7. The cold temperate conifer forest zone had the largest proportion of fire degradation, accounting for 67.7% of the area, and totals of 99.0% of the subtropical evergreen broadleaf forest zone and 92.8% of the temperate conifer and broadleaf mixed forest zone were moderately to severely affected by drought, with long-term stability. Additionally, 0.1% of the temperate grassland region and 0.1% of the cold temperate conifer forest zone underwent severe pest infestations, with a long-term stable trend. Meteorological factors were the primary contributors to all typical degradation patterns, accounting for 81.35%, 58.70%, and 82.29%, respectively. The research developed an index for assessing forest degradation and explained the importance of natural and anthropogenic factors in forest degradation. The results are beneficial for the scientific management of forest degradation and for improving forest management efficiency. [ABSTRACT FROM AUTHOR]

COVID-19 posed challenges for global tourism management. Changes in visitor temporal and spatial patterns and their associated determinants pre- and peri-pandemic in Canadian Rocky Mountain National Parks are analyzed. Data was collected through social media programming and analyzed using spatiotemporal analysis and a geographically weighted regression (GWR) model. Results highlight that COVID-19 significantly changed park visitation patterns. Visitors tended to explore more remote areas peri-pandemic. The GWR model also indicated distance to nearby trails was a significant influence on visitor density. Our results indicate that the pandemic influenced tourism temporal and spatial imbalance. This research presents a novel approach using combined social media big data which can be extended to the field of tourism management, and has important implications to manage visitor patterns and to allocate resources efficiently to satisfy multiple objectives of park management. [ABSTRACT FROM AUTHOR]

Atmospheric acid deposition disrupted terrestrial-aquatic carbon cycling by drastically lowering dissolved organic carbon (DOC) loads in many lakes across NE North America and northern Europe during the 20th century. However, little is known about how acid deposition has altered the role of lakes as long-term carbon sinks. We present contemporary (n = 80) organic carbon accumulation rates (OCAR) and OCAR trends over the past ~ 150 years (n = 8), and other supporting infrared spectroscopic, isotopic, and elemental geochemical proxies, for lakes in and near Sudbury, Ontario, Canada – an area heavily affected by acid deposition from smelting activities in the late-19th and 20th centuries. Contemporary OCAR varied between 4.9 and 35.3 g m–2 yr–1 among study lakes (mean: 13.5±6.4 g m–2 yr–1). Sediment-inferred trends in lake-water DOC showed a strong response in DOC loadings to the effects of acid deposition during the past century, which is corroborated by increasing observed lake-water DOC concentrations (i.e., lake browning) since the 1980s. Despite these changes in DOC, as well as changes in water acidity, only lakes with direct physical watershed disturbances showed short-lived increases in OCAR, whereas OCAR changed little in remote Sudbury-region lakes with minimal direct human disturbances (mean OCAR: 14.3 ± 8.7 g m–2 yr–1). This is in stark contrast to many other northern forest lakes with minimal direct catchment disturbances that experienced significant increases in OCAR during the 20th century. Our results caution that lake browning may not be a dominant driver behind the widespread increase in organic C burial in northern lakes during recovery from acid deposition in recent decades. [ABSTRACT FROM AUTHOR]

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

Dissolved organic matter (DOM), often measured as dissolved organic carbon (DOC), plays a fundamental role in influencing the structure and function of lake ecosystems. Due to the myriad ecosystem effects of DOM, widespread observations of long‐term increasing DOM concentrations have received much attention from ecologists. DOM positively influences primary production and consumer production at low concentrations due to the fertilising influence of bound nutrients. However, beyond a unimodal peak in production, a reduced light environment may result in a negative effect on production. This unimodal model has been largely developed and tested in lakes with low to moderate DOM concentrations (i.e., typically ≤10 mg/L DOC).To understand ecological responses in lakes across a larger range in DOM concentrations, we examined the response of benthic invertebrate communities in 148 Swedish lakes with DOM concentrations ranging between 0.67 and 32.77 mg/L DOC.We found that increasing DOM concentrations had a strong effect on invertebrate community composition below c. 10 mg/L. Across this range, abundances of individual taxa both increased and decreased, probably in response to environmental change induced by DOM. However, in lakes above this concentration, increasing DOM had minimal influence on community composition.As DOM concentrations continue to increase, faunal communities in lakes below this 10 mg/L DOC threshold are likely to undergo substantial change whereas those above this threshold are likely to be minimally impacted. [ABSTRACT FROM AUTHOR]

The effects of climate change on vegetation composition and distribution are evident in different ecosystems around the world. Although some climate‐derived alterations on vegetation are expected to result in changes in lifeform fractional cover, disentangling the direct effects of climate change from different non‐climate factors, such as land‐use change, is challenging. By applying "Liebig's law of the minimum" in a geospatial context, we determined the climate‐limited potential for tree, shrub, herbaceous, and non‐vegetation fractional cover change for the conterminous United States and compared these potential rates to observed change rates for the period 1986 to 2018. We found that 10% of the land area of the conterminous United States appears to have climate limitations on the change in fractional cover, with a high proportion of these sites located in arid and semiarid ecosystems in the Southwest part of the country. The rates of change in lifeform fractional cover for the remaining area of the country are likely limited by non‐climate factors such as the disturbance regime, land management, land‐use history, soil conditions, and species interactions and adaptations. [ABSTRACT FROM AUTHOR]

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

The Arctic is the fastest warming biome on the planet, and environmental changes are having striking effects on freshwater ecosystems that may impact the regional carbon cycle. The metabolic state of Arctic lakes is often considered net heterotrophic, due to an assumed supply of allochthonous organic matter that supports ecosystem respiration and carbon mineralization in excess of rates of primary production. However, lake metabolic patterns vary according to regional climatic characteristics, hydrological connectivity, organic matter sources and intrinsic lake properties, and the metabolism of most Arctic lakes is unknown. We sampled 35 waterbodies along a connectivity gradient from headwater to downstream lakes, on southern Victoria Island, Nunavut, in an area characterized by low precipitation, organic‐poor soils, and high evaporation rates. We evaluated whether lakes were net autotrophic or heterotrophic during the open water period using an oxygen isotopic mass balance approach. Most of the waterbodies were autotrophic and sites of net organic matter production or close to metabolic equilibrium. Autotrophy was associated with higher benthic primary production, as compared to its pelagic counterpart, due to the high irradiance reaching the bottom and efficient internal carbon and nutrient cycling. Highly connected midstream and downstream lakes showed efficient organic matter cycling, as evidenced by the strong coupling between gross primary production (GPP) and ecosystem respiration, while decoupling was observed in some headwater lakes with significantly higher GPP. The shallow nature of lakes in the flat, arid region of southern Victoria Island supports net autotrophy in most lakes during the open water season. Ongoing climate changes that lengthen the ice‐free irradiance period and increase rates of nutrient evapoconcentration may further promote net autotrophy, with uncertain long‐term effects for lake functioning. [ABSTRACT FROM AUTHOR]

Macroinvertebrates play a vital role in coastal ecosystems and are an important indicator of ecosystem quality. Both anthropogenic activity and environmental changes may lead to significant changes in the marine macroinvertebrate community. However, the assembly process of benthic biodiversity and its mechanism driven by environmental factors at large scales remains unclear. Here, using the benthic field survey data of 15 years at large spatial and temporal scales from the Yellow Sea Large Marine Ecosystem, we investigated the relative importance of environmental selection, dispersal processes, random‐deterministic processes of macroinvertebrates community diversity assembly, and the responses of this relative importance driven by temperature and nutrients. Results showed that the macroinvertebrates community diversity is mainly affected by dispersal. Nitrogen and phosphorus are the most important negative factors among environmental variables, while geographical distance is the main limiting factor of β diversity. Within the range of 0.35–0.70 mg/L of nutrients, increasing nutrient concentration can significantly facilitate the contribution of the decay effect to β diversity. Within the temperature range studied (15.0–18.0°C), both warming and cooling can lead to a greater tendency for species diversity assembly processes to be dominated by deterministic processes. The analysis contributes to a better understanding of the assembly process of the diversity of coastal marine macroinvertebrates communities and how they adapt to global biogeochemical processes. [ABSTRACT FROM AUTHOR]

In recent years, there has been an increase in the pressure exerted by physical and sporting activities in the natural environment. In Spain, mountaineering, which usually takes place in Protected Natural Areas, is the first option in the order of preference of people who practice sport. Knowing the profile of visitors is a key aspect in managing public use of these environments. The objectives of the study focused on i) characterising the generic profile of mountaineers on Spain's emblematic summits and ii) identifying behavioural patterns with a view to contributing to a more sustainable management of these natural environments. The study was based on a survey of mountaineers who climbed one of the following summits during the summer of 2020: Mulhacén, Monte Perdido, Aneto, Pica d'Estats, and Pedraforca, with a sample of 578 participants. The main results obtained include the identification of an average profile characterised by being: male, between 26 and 35 years old, with a high level of education, with more than 10 years of seniority in mountaineering and a high degree of environmental sensitivity. Another of the results of this study was the observation of common patterns of behaviour when visiting the different summits. The results obtained were analysed in terms of their application to the overall management of mountaineering in this type of protected natural environment. [ABSTRACT FROM AUTHOR]

While spatial distribution shifts have been documented in many marine fishes under global change, the responses of elasmobranchs have rarely been studied, which may have led to an underestimation of their potential additional threats. Given their irreplaceable role in ecosystems and their high extinction risk, we used a 24‐year time series (1997–2020) of scientific bottom trawl surveys to examine the effects of climate change on the spatial distribution of nine elasmobranch species within Northeast Atlantic waters. Using a hierarchical modeling of species communities, belonging to the joint species distribution models, we found that suitable habitats for four species increased on average by a factor of 1.6 and, for six species, shifted north‐eastwards and/or to deeper waters over the past two decades. By integrating species traits, we showed changes in habitat suitability led to changes in the elasmobranchs trait composition. Moreover, communities shifted to deeper waters and their mean trophic level decreased. We also note an increase in the mean community size at maturity concurrent with a decrease in fecundity. Because skates and sharks are functionally unique and dangerously vulnerable to both climate change and fishing, we advocate for urgent considerations of species traits in management measures. Their use would make it better to identify species whose loss could have irreversible impacts in face of the myriad of anthropogenic threats. [ABSTRACT FROM AUTHOR]

Fire is a dominant force shaping patterns of plant diversity in Mediterranean‐type ecosystems. In these biodiversity hotspots, including California's endangered coastal scrub, many species remain hidden belowground as seeds and bulbs, only to emerge and flower when sufficient rainfall occurs after wildfire. The unique adaptations possessed by these species enable survival during prolonged periods of unfavorable conditions, but their continued persistence could be threatened by nonnative plant invasion and environmental change. Furthermore, their fleeting presence aboveground makes evaluating these threats in situ a challenge. For example, nitrogen (N) deposition resulting from air pollution is a well‐recognized threat to plant diversity worldwide but impacts on fire‐following species are not well understood. We experimentally evaluated the impact of N deposition on post‐fire vegetation cover and richness for three years in stands of coastal sage scrub that had recently burned in a large wildfire in southern California. We installed plots receiving four levels of N addition that corresponded to the range of N deposition rates in the region. We assessed the impact of pre‐fire invasion status on vegetation dynamics by including plots in areas that had previously been invaded by nonnative grasses, as well as adjacent uninvaded areas. We found that N addition reduced native forb cover in the second year post‐fire while increasing the abundance of nonnative forbs. As is typical in fire‐prone ecosystems, species richness declined over the three years of the study. However, N addition hastened this process, and native forb richness was severely reduced under high N availability, especially in previously invaded shrublands. An indicator species analysis also revealed that six functionally and taxonomically diverse forb species were especially sensitive to N addition. Our results highlight a new potential mechanism for the depletion of native species through the suppression of ephemeral post‐fire bloom events. [ABSTRACT FROM AUTHOR]

External nutrient loading can cause large changes in freshwater ecosystems. Many local field and laboratory experiments have investigated ecological responses to nutrient addition. However, these findings are difficult to generalize, as the responses observed may depend on the local context and the resulting nutrient concentrations in the receiving water bodies. In this research, we combined and analysed data from 131 experimental studies containing 3054 treatment‐control abundance ratios to assess the responses of freshwater taxa along a gradient of elevated nutrient concentrations. We carried out a systematic literature search in order to identify studies that report the abundance of invertebrate, macrophyte, and fish taxa in relation to the addition of nitrogen, phosphorus, or both. Next, we established mixed‐effect meta‐regression models to relate the biotic responses to the concentration gradients of both nutrients. We quantified the responses based on various abundance‐based metrics. We found no responses to the mere addition of nutrients, apart from an overall increase of total invertebrate abundance. However, when we considered the gradients of N and P enrichment, we found responses to both nutrients for all abundance metrics. Abundance tended to increase at low levels of N enrichment, yet decreased at the high end of the concentration gradient (1–10 mg/L, depending on the P concentration). Responses to increasing P concentrations were mostly positive. For fish, we found too few data to perform a meaningful analysis. The results of our research highlight the need to consider the level of nutrient enrichment rather than the mere addition of nutrients in order to better understand broad‐scale responses of freshwater biota to eutrophication, as a key step to identify effective conservation strategies for freshwater ecosystems. [ABSTRACT FROM AUTHOR]

Increasing trends of atmospheric nitrogen (N) deposition resulting from a large number of anthropogenic emissions of reactive N are dramatically altering the global biogeochemical cycle of N. Nitrogen uptake by mosses mainly from the atmosphere, making it a competent bio-indicator for N deposition. However, high uncertainties exist when using mosses to indicate N deposition, especially in choosing sampling period and sampling frequency. In this study, atmospheric N deposition and moss N content in the urban-agro-forest transition, a region with a high N deposition level of 27.46~43.70 kg N hm-2 yr-1, were monitored, and the method for atmospheric N deposition monitoring by mosses was optimized. We found that the optimal sampling frequency is within six months per time, and the optimal sampling time is autumn (October and November) and summer (July and August), which gives us a better estimation for atmospheric N deposition than other scenarios. In addition, the moss N content could better indicate total N deposition than the deposition of specific N species. This study eventually allowed moss to be used more effectively and sensibly as an indicator of atmospheric N deposition and helped to improve the accuracy of the model of quantifying N deposition by using mosses. [ABSTRACT FROM AUTHOR]

The Uncompahgre fritillary butterfly (Boloria improba acrocnema Gall LF, Sperling FAH (1980) A new high altitude species of Boloria from southwestern Colorado (Nyphalidae), with a discussion of phenetics and hierarchical decisions. J Lepidopterists' Soc 34:230–252 1980) was listed as federally endangered in 1991 and is considered a habitat indicator for alpine ecosystem health. They are found on patches of Salix nivalis in isolated habitats of the San Juan Mountains, Colorado, USA. Here, we estimated historical B. i. acrocnema abundance from annual distance sampling (2003–2020) at seven sub-colonies and sampled current (July 2021) measurements of herbaceous coverage, soil moisture content, and slope, aspect, and elevation at 700 sample sites. We used regression models to test the effects of these microhabitat characteristics on historical abundance. Our results show that increases in slope from 11° to 31°, individual coverage of five alpine plant species (S. nivalis, Geum rossii, Phacelia sericea, Noccaea fendleri, and Lewisia pygmaea), and soil moisture content between 0.09 m3/m3 and 0.38 m3/m3 positively influence butterfly abundance. However, increases in elevation, bare ground coverage, and presence of Salix planifolia, Aster alpinus, Antennaria media, and Androsace chamaejasme were correlated with lower abundance estimates. Implications for insect conservation Effects of climate change which decrease coverage of these alpine plant species, allow encroachment of lower elevation species, or reduce soil moisture will decrease B. i. acrocnema abundance. These results emphasize the extinction risk of B. i. acrocnema due to range limitations and prolonged drought conditions in the Western U.S. By defining additional resource requirements of B. i. acrocnema, we can model climate effects on survivorship and consider nearby microhabitats that may be habitable by this endangered species. [ABSTRACT FROM AUTHOR]

Forest decline events have increased worldwide over the last decades being holm oak (Quercus ilex L.) one of the tree species with the most worrying trends across Europe. Since this is one of the tree species with the southernmost distribution within the European continent, its vulnerability to climate change is a phenomenon of enormous ecological importance. Previous research identified drought and soil pathogens as the main causes behind holm oak decline. However, despite tree health loss is a multifactorial phenomenon where abiotic and biotic factors interact in time and space, there are some abiotic factors whose influence has been commonly overlooked. Here, we evaluate how land use (forests versus savannas), topography, and climate extremes jointly determine the spatiotemporal patterns of holm oak defoliation trends over almost three decades (1987–2014) in Spain, where holm oak represents the 25% of the national forested area. We found an increasing defoliation trend in 119 out of the total 134 holm oak plots evaluated, being this defoliation trend significantly higher in forests compared with savannas. Moreover, we have detected that the interaction between topography (which covariates with the land use) and summer precipitation anomalies explains trends of holm oak decline across the Mediterranean region. While a higher occurrence of dry summers increases defoliation trends in steeper terrains where forests dominate, an inverse relationship was found in flatter terrains where savannas are mainly located. These opposite relationships suggest different causal mechanisms behind decline. Whereas hydric stress is likely to occur in steeper terrains where soil water holding capacity is limited, soil waterlogging usually occurs in flatter terrains what increases tree vulnerability to soil pathogens. Our results contribute to the growing evidence of the influence of local topography on forest resilience and could assist in the identification of potential tree decline hotspots and its main causes over the Mediterranean region. [ABSTRACT FROM AUTHOR]

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Aim: Strong social‐ecological trade‐offs between resource extraction and protection have created challenges for large, protected area management in natural resource‐dependent countries. Therefore, local governments and community conservation activities are becoming common and information about low environmental exposure and high biodiversity can provide for planning localized conservation activities. Location: The western Indian Ocean. Methods: Coral reef sites were evaluated for local‐scale environmental and species richness to elucidate local patterns in spatial heterogeneity. Local coral and fish taxonomic richness and coral community susceptibility to stress were normalized to partially account for common and heterogenous disturbances to coral cover and fish biomass. Residuals of these three response variables were evaluated for local geographic patterns and specific relationships with 21 environmental variables using machine learning methods. Results: Richness was highly variable at local geographies and had a double‐peaked shape with latitudes. Thirteen of the 21 examined variables were selected and indicated complex, spatially heterogeneous and weak cumulative predictive relationships with specific environmental and human influences. For example, each selected variable contributed 7% to 25% of the variance but with different relationships for the three responses. Coral fish richness and coral community susceptibility correlations were positive but weak and therefore produced different local spatial patterns. Nevertheless, these spatial patterns exhibited some coarse‐scale similarities indicating locations with shared positive community attributes and potential climate refugia. Shared richness variables included depth and wave energy, temperature variables of SST skewness, excess heat and rate of rise. Human influences of distance to shore, human populations and cities were also selected for richness and community susceptibility responses. Main Conclusions: Planning to include local stress and richness patterns variability could contribute to species persistence. From these specific data, sites in the Pemba Channel between the Tanzanian mainland and Pemba Island, and northern Mozambique and Madagascar fit refugia characteristics. [ABSTRACT FROM AUTHOR]

On a global scale, rangelands occupy approximately half of the world's land base surface; have a critical role in carbon sequestration and biodiversity; and support a diverse and critical economy, but at the same time, are under threat by many factors, including climate change. California rangelands, which are no exception to these aforementioned characteristics, are also unique socio-ecological systems that provide a broad range of ecosystem services and support a >$3 billion annual cattle ranching industry. However, climate change both directly and indirectly poses significant challenges to the future sustainability of California rangelands and, ultimately, the management of livestock, which has important economic implications for the state's agricultural economy. In this study, we examined the changes in overall climate exposure and climatic water deficit (CWD), which was used as a physiological plant water stress gauge, to evaluate potential impacts of climate change on various rangeland vegetation types across California. We used two downscaled global climate models, MIROC and CNRM, under the 'business-as-usual' emissions scenario of RCP8.5 at a mid-century time horizon of 2040–2069 and known vegetation–climate relationships. Using the models, we predicted climate change effects using metrics and spatial scales that have management relevance and that can support climate-informed decision making for livestock managers. We found that more than 80% of the area of the rangeland vegetation types considered in this study will have higher CWD by 2040–2069. We evaluated these results with beef cattle inventory data from the U.S. Department of Agriculture by county and found that, on average, 71.6% of rangelands in the top 30 counties were projected to be highly climate-stressed. We found that current proactive and reactive ranching practices such as resting pastures, reducing herd size, and rotational grazing may need to be expanded to include additional strategies for coping with declining plant productivity. [ABSTRACT FROM AUTHOR]

Human activities and climate change threaten coldwater organisms in freshwater ecosystems by causing rivers and streams to warm, increasing the intensity and frequency of warm temperature events, and reducing thermal heterogeneity. Cold‐water refuges are discrete patches of relatively cool water that are used by coldwater organisms for thermal relief and short‐term survival. Globally, cohesive management approaches are needed that consider interlinked physical, biological, and social factors of cold‐water refuges. We review current understanding of cold‐water refuges, identify gaps between science and management, and evaluate policies aimed at protecting thermally sensitive species. Existing policies include designating cold‐water habitats, restricting fishing during warm periods, and implementing threshold temperature standards or guidelines. However, these policies are rare and uncoordinated across spatial scales and often do not consider input from Indigenous peoples. We propose that cold‐water refuges be managed as distinct operational landscape units, which provide a social and ecological context that is relevant at the watershed scale. These operational landscape units provide the foundation for an integrated framework that links science and management by (1) mapping and characterizing cold‐water refuges to prioritize management and conservation actions, (2) leveraging existing and new policies, (3) improving coordination across jurisdictions, and (4) implementing adaptive management practices across scales. Our findings show that while there are many opportunities for scientific advancement, the current state of the sciences is sufficient to inform policy and management. Our proposed framework provides a path forward for managing and protecting cold‐water refuges using existing and new policies to protect coldwater organisms in the face of global change. [ABSTRACT FROM AUTHOR]

Nitrogen (N) deposition has increased substantially since the second half of the 20th century due to human activities. This increase of reactive N into the biosphere has major implications for ecosystem functioning, including primary production, soil and water chemistry and producer community structure and diversity. Increased N deposition is also linked to the decline of insects observed over recent decades. However, we currently lack a mechanistic understanding of the effects of high N deposition on individual fitness, species richness and community structure of both invertebrate and vertebrate consumers. Here, we review the effects of N deposition on producer–consumer interactions, focusing on five existing ecological frameworks: C:N:P ecological stoichiometry, trace element ecological stoichiometry, nutritional geometry, essential micronutrients and allelochemicals. We link reported N deposition‐mediated changes in producer quality to life‐history strategies and traits of consumers, to gain a mechanistic understanding of the direction of response in consumers. We conclude that high N deposition influences producer quality via eutrophication and acidification pathways. This makes oligotrophic poorly buffered ecosystems most vulnerable to significant changes in producer quality. Changes in producer quality between the reviewed frameworks are often interlinked, complicating predictions of the effects of high N deposition on producer quality. The degree and direction of fitness responses of consumers to changes in producer quality varies among species but can be explained by differences in life‐history traits and strategies, particularly those affecting species nutrient intake regulation, mobility, relative growth rate, host‐plant specialisation, ontogeny and physiology. To increase our understanding of the effects of N deposition on these complex mechanisms, the inclusion of life‐history traits of consumer species in future study designs is pivotal. Based on the reviewed literature, we formulate five hypotheses on the mechanisms underlying the effects of high N deposition on consumers, by linking effects of nutritional ecological frameworks to life‐history strategies. Importantly, we expect that N‐deposition‐mediated changes in producer quality will result in a net decrease in consumer community as well as functional diversity. Moreover, we anticipate an increased risk of outbreak events of a small subset of generalist species, with concomitant declines in a multitude of specialist species. Overall, linking ecological frameworks with consumer life‐history strategies provides a mechanistic understanding of the impacts of high N deposition on producer–consumer interactions, which can inform management towards more effective mitigation strategies. [ABSTRACT FROM AUTHOR]

Climate change and atmospheric deposition of nitrogen (N) and sulfur (S) are important drivers of forest demography. Here we apply previously derived growth and survival responses for 94 tree species, representing >90% of the contiguous US forest basal area, to project how changes in mean annual temperature, precipitation, and N and S deposition from 20 different future scenarios may affect forest composition to 2100. We find that under the low climate change scenario (RCP 4.5), reductions in aboveground tree biomass from higher temperatures are roughly offset by increases in aboveground tree biomass from reductions in N and S deposition. However, under the higher climate change scenario (RCP 8.5) the decreases from climate change overwhelm increases from reductions in N and S deposition. These broad trends underlie wide variation among species. We found averaged across temperature scenarios the relative abundance of 60 species were projected to decrease more than 5% and 20 species were projected to increase more than 5%; and reductions of N and S deposition led to a decrease for 13 species and an increase for 40 species. This suggests large shifts in the composition of US forests in the future. Negative climate effects were mostly from elevated temperature and were not offset by scenarios with wetter conditions. We found that by 2100 an estimated 1 billion trees under the RCP 4.5 scenario and 20 billion trees under the RCP 8.5 scenario may be pushed outside the temperature record upon which these relationships were derived. These results may not fully capture future changes in forest composition as several other factors were not included. Overall efforts to reduce atmospheric deposition of N and S will likely be insufficient to overcome climate change impacts on forest demography across much of the United States unless we adhere to the low climate change scenario. [ABSTRACT FROM AUTHOR]

Meadows are valuable areas that play an important role in the carbon cycle. Depending on several factors, these areas can be carbon sinks or net emitters of carbon dioxide (CO2) into the atmosphere. In the present study, the use of an antitranspirant (AT) with silicon and the groundwater level in a subirrigation system in a three-cut meadow were evaluated on the carbon dioxide exchange balance and the yield of aboveground biomass. The study was carried out in four experimental plots: with high groundwater level (HWL), with a high water level with AT application (HWL_Si), with a lower groundwater level (LWL), and with a lower groundwater level and AT application (LWL_Si). Flux measurements were made using the closed dynamic chamber method. In the drier and colder 2021, the meadow was a net CO2 emitter (mean annual net ecosystem exchange (NEE) of all plots: +247.4 gCO2-C·m−2y−1), whereas in the more wet and warmer 2022, assimilation outweighed emissions (mean annual NEE of all plots: −187.4 gCO2-C·m−2y−1). A positive effect of the silicon antitranspirant application was observed on the reduction of carbon dioxide emissions and the increase of gross primary production (GPP) from the plots with higher groundwater levels. For the area with lower water levels, the positive impact of AT occurred only in the second year of the experiment. The yield of aboveground biomass was higher by 5.4% (in 2021) up to 11.7% (in 2022) at the plot with the higher groundwater level. However, the application of AT with silicon contributed to yield reduction in each cut, regardless of the groundwater level. On an annual basis, AT application with silicon reduced the yield by 11.1–17.8%. [ABSTRACT FROM AUTHOR]

Increased nitrogen (N) and phosphorus (P) availability, due to fertilization and deposition, is expected to influence soil microbial community structure and function. However, little is known about the sensitivity and dependency of soil microbial structure on the levels of N and P, and on the integration of N and P inputs in alpine meadow ecosystems. Here, we implemented a 3‐year manipulative fertilization study with four levels (0, 10, 20, and 30 g m−2) of N fertilization, P fertilization, and NP fertilization (N and P fertilization at a ratio of 1:1) in a Tibetan alpine meadow. We examined how greater N and P availability affected bacterial community diversity, community structure in the top‐ (0–10 cm) and sub‐top (10–20 cm) soil, network topological properties, and the potential mechanisms behind them. Although the α and β diversities of bacteria within top‐ and sub‐topsoil were not significantly different from those in the control across N, P, and NP fertilization levels, the integration of NP fertilization significantly changed the relative abundances of more bacterial phyla than the N and P fertilization did separately. Furthermore, the N10 and N20 fertilization treatments strengthened bacterial interactions, whereas P and NP fertilization did not affect the complexity and connectivity of the soil bacterial co‐occurrence network. In addition, the mechanism of structuring the bacterial community for separate N and P fertilization differed from that for NP fertilization. The separate application of N and P fertilization affected the bacterial community composition mainly through changes in the total and available P levels in the soil, respectively, whereas NP fertilization shifted the bacterial community composition through decreasing plant species richness. These findings provide a quantification of the response of soil bacterial diversity and composition to different levels of N, P, and NP fertilization. It also suggests that in the Tibetan alpine meadow, soil bacterial communities may alter their fitness according to the relative abundances of oligotrophic/copiotrophic bacterial taxa, rather than through changing their diversity. [ABSTRACT FROM AUTHOR]

Understanding the impact and dynamics of invasive alien species (IAS) is essential for tailoring appropriate management plans. This information can be difficult to obtain in the short term, and intrinsic difficulties of monitoring hard‐to‐reach areas may hamper prompt estimation of IAS distributions. Using the case of the invasive Asian common toad (Duttaphrynus melanostictus) in Madagascar, we show how public surveys coupled with a multi‐analytical approach can promptly provide accurate information on invasion dynamics and impacts. On the basis of key‐informant responses, we built polynomial regressions to investigate the spatiotemporal invasion patterns, false‐positive occupancy models to estimate species occupancy, and mixed‐effect models to evaluate the public perception and attitudes. The invasion followed a linear expansion of approx. 2 km year−1, with human‐mediated dispersal facilitating the spread of the species. Toad occupancy decreased towards the invasion front and increased in the southern portion of its range. Negative perception decreased in urban areas, where people were less concerned by toad impacts on ecosystems, and in recently invaded localities, suggesting density‐ or time‐dependent effects. We also identified 12 potential impacts, with "loss of domestic apiaries", "poisoning of poultry" and "decline of snakes" standing out for prevalence and potential severity. Our results bring important insights into the invasion dynamics and the human‐toad interactions in Madagascar, highlighting the versatility of public surveys to obtain essential information for invasion science and management, which can be especially useful in hard‐to‐monitor regions of the world with a low in‐country capacity to counter invasive species. [ABSTRACT FROM AUTHOR]

Environmental communication interventions are employed in nature-based tourism settings to achieve environmental protection. However, much still needs to be studied to understand what interventions work, how and why. This review summarises the research design and outcomes of 54 empirical studies, published in English-language peer-reviewed journals where communications were used to foster visitors' pro-environmental intentions or actual behaviours. Our analysis suggests that environmental communication can be a useful tool although mixed results were often observed. Personal interpretation interventions were slightly more common than non-personal communications, and produced a higher portion of positive changes in pro-environmental behaviors and intentions. The use of Theory of Planned Behaviour was most commonly observed. Research on the efficacy of environmental communications is increasing; we suggest priorities to guide this accelerating research activity. Under-researched communications approaches include visual communications and digital tools. Increased comparison of content and delivery modes within the same study and in different nature-tourism contexts is needed, especially with diverse populations (e.g. cultural) and distinct sub-groups (e.g. pro- vs. non-environmental market segments). We advocate for increased diversity of research methods (e.g. qualitative) and robust design (e.g. longitudinal) to better understand visitors' behaviours, with reduced use of attitudes, knowledge and intentions as dependent variables. [ABSTRACT FROM AUTHOR]

Recent declines in once‐common species are triggering concern that an environmental crisis point has been reached. Yet, the lack of long abundance time series data for most species can make it difficult to attribute these changes to anthropogenic causes, and to separate them from normal cycles. Genetic diversity, on the other hand, is sensitive to past and recent environmental changes, and reflects a measure of a populations' potential to adapt to future stressors. Here, we consider whether patterns of genetic diversity among aquatic insects can be linked to historical and recent patterns of land use change. We collated mitochondrial cytochrome c oxidase subunit I (COI) variation for >700 aquatic insect species across the United States, where patterns of agricultural expansion and intensification have been documented since the 1800s. We found that genetic diversity was lowest in regions where cropland was historically (pre‐1950) most extensive, suggesting a legacy of past environmental harm. Genetic diversity further declined where cropland has since expanded, even after accounting for climate and sampling effects. Notably though, genetic diversity also appeared to rebound where cropland has diminished. Our study suggests that genetic diversity at the community level can be a powerful tool to infer potential population declines and rebounds over longer time spans than is typically possible with ecological data. For the aquatic insects that we considered, patterns of land use many decades ago appear to have left long‐lasting damage to genetic diversity that could threaten evolutionary responses to rapid global change. see also the Perspective by Lane M. Atmore and Danielle L. Buss [ABSTRACT FROM AUTHOR]

Recent studies highlight the potential of climate change refugia (CCR) to support the persistence of biodiversity in regions that may otherwise become unsuitable with climate change. However, a key challenge in using CCR for climate resilient management lies in how CCR may intersect with existing forest management strategies, and subsequently influence how landscapes buffer species from negative impacts of warming climate. We address this challenge in temperate coastal forests of the Pacific Northwestern United States, where declines in the extent of late‐successional forests have prompted efforts to restore old‐growth forest structure. One common approach for doing so involves selectively thinning forest stands to enhance structural complexity. However, dense canopy is a key forest feature moderating understory microclimate and potentially buffering organisms from climate change impacts, raising the possibility that approaches for managing forests for old‐growth structure may reduce the extent and number of CCR. We used remotely sensed vegetation indices to identify CCR in an experimental forest with control and thinned (restoration) treatments, and explored the influence of biophysical variables on buffering capacity. We found that remotely sensed vegetation indices commonly used to identify CCR were associated with understory temperature and plant community composition, and thus captured aspects of landscape buffering that might instill climate resilience and be of interest to management. We then examined the interaction between current restoration strategies and CCR, and found that selective thinning for promoting old‐growth structure had only very minor, if any, effects on climatic buffering. In all, our study demonstrates that forest management approaches aimed at restoring old‐growth structure through targeted thinning do not greatly decrease buffering capacity, despite a known link between dense canopy and CCR. More broadly, this study illustrates the value of using remote sensing approaches to identify CCR, facilitating the integration of climate change adaptation with other forest management approaches. [ABSTRACT FROM AUTHOR]

In the context of climate change, the occurrence of water stress in forest ecosystems, which are solely dependent on precipitation, has exhibited a rising trend, even among species that are typically regarded as drought-tolerant. Remote sensing techniques offer an efficient, comprehensive, and timely approach for monitoring forests at local and regional scales. These techniques also enable the development of diverse indicators of plant water status, which can play a critical role in evaluating forest water stress. This review aims to provide an overview of remote sensing applications for monitoring water stress in forests and reveal the potential of remote sensing and geographic information system applications in monitoring water stress for effective forest resource management. It examines the principles and significance of utilizing remote sensing technologies to detect forest stress caused by water deficit. In addition, by a quantitative assessment of remote sensing applications of studies in refereed publications, the review highlights the overall trends and the value of the widely used approach of utilizing visible and near-infrared reflectance data from satellite imagery, in conjunction with classical vegetation indices. Promising areas for future research include the utilization of more adaptable platforms and higher-resolution spectral data, the development of novel remote sensing indices with enhanced sensitivity to forest water stress, and the implementation of modelling techniques for early detection and prediction of stress. [ABSTRACT FROM AUTHOR]

Information Technology tools have evolved and can be useful in bringing society closer to the administration of Protected Areas through Citizen Science-type initiatives. This study developed and tested two tools for National Parks (NPs) (Beta versions): 1) a cellphone app (Parceir@s Parques Nacionais), and 2) a website (Conserva Parques) that we hope will enable users to interact with NP managers who can gain more direct access to visitors' perceptions. The app's goal is to establish user-manager interactions through the registration of occurrences in the NPs, and through the website, thus providing society with a prediction of the degree of nature conservation in NPs by making hypothetical alterations to public use variables. The perceptions of those "beta-testers" were registered in an online form. Both tools achieved approval ratings of over 75%. The conclusion is that the testing of both tools developed in this study can progress to a phase directly with NP users. [ABSTRACT FROM AUTHOR]

Remote mountain lakes in protected areas are sentinels of the ecological impacts of extreme and novel environmental changes occurring at broad regional scales. Ecosystem responses to such stressors are often first detected as shifts in community composition. We surveyed phytoplankton communities across 82 mountain lakes to test the hypothesis that taxonomic composition is indicative of more environmental changes than are aggregate properties, such as total biomass. Phosphorus was the only significant predictor of chlorophyll-inferred algal biomass, a correlative finding supported by evidence from our nutrient amendment bioassays. Interlake variances in taxonomically diagnostic algal pigments and 78 genera were indicative of changes in total phosphorus, glacial coverage, underwater light availability, and dissolved organic carbon. Lack of concordance was observed between ordinations of pigment- and genus-based data as environmental variables captured more variance in the pigment data. Our findings provide a baseline for future lake monitoring programs in the Canadian Rockies as they increasingly experience interactive effects involving climate change and landscape features, such as variation in turbid glacial meltwaters and aeolian phosphorus deposition from wildfires. [ABSTRACT FROM AUTHOR]

Current temperatures in microrefugia may persist longer than in nearby areas as temperatures warm. However, locating and measuring the contribution of microrefugia to thermal inertia in a landscape is challenging. We measured the thermal buffering capacity of microrefugia across a 40,000 km2 region of complex mountain topography by quantifying environmental lapse rate and solar radiation effects on air temperature in 0.1 km2 hexagons, a resource management‐relevant scale for climate adaptation. The greatest buffering capacity is −1.62°C, and only 2.8% of the region can buffer 1°C or greater. Historical loss of local cooling capacity is low, but by 2069 only 6.9%–11% of the region retains baseline temperature conditions. This thermal buffer index can find the most climate change‐buffered areas in lands identified as high priority for habitat conservation, wildlife corridors, and forest preservation. Other processes such as cold air pooling can complement our approach but depend on additional factors. Plain Language Summary: Microrefugia are areas where local climate conditions may persist longer as temperatures warm because of their topographic features, which include the level of solar radiation and the elevation range they contain. Such areas are of conservation interest because their potential to retain current climate conditions longer, as global warming continues may be of particular importance for species with low dispersal capabilities. We modeled these features across a large mountainous region using 10 ha (25 acre) hexagons. The use of a standard size permitted inter‐comparison of 404,700 units to identify their relative capacity to retain their climate conditions from a temporal baseline of 1981–2010. We found that warming between the 1951–1980 and the baseline only affected about 14% of the region. However, by 2069, only 6.9%–11% of the hexagons still retained the conditions from baseline period, and by 2100 less than 1% of the landscape retains the baseline temperature conditions. The identification of hexagons with the most temperature buffering capacity can inform a number of land management and conservation strategies. We illustrate their use in frameworks for preserving vegetation types, landscape connectivity protection, and late seral forest preservation. Key Points: Species with low dispersal capacity may depend on local microrefugia to persist as temperatures warmOver a 40,250 km2 area, we found that microrefugia buffering capacity at 10 ha scale is only retained in ∼6.9%–11% of the region by 2069Quantifying local capacity to retain baseline temperatures can be used in a variety of natural resource strategies for climate adaptation [ABSTRACT FROM AUTHOR]

Widespread tree mortality events occur during periods of severe drought in temperate conifer forests and are expected to become more frequent in many areas due to climate change. Improved mapping of individual tree mortality is needed to identify risk factors and design effective conservation strategies. In this study, we used National Ecological Observatory Network (NEON) lidar and multispectral reflectance airborne observations to map individual tree mortality over a 160 km2 area during and after the 2012–2016 drought for two sites in California's Sierra National Forest. We used NEON lidar to derive tree locations and crown perimeters and multispectral data to map tree mortality for more than 1 million trees. We found that 25.4% of the trees in our study area died between 2013 and 2017, with considerably higher mortality at the lower‐elevation Soaproot Saddle site. Between 2017 and 2019, an additional 2.0%–2.8% of the trees died each year. Two wildfires in 2020 and 2021 increased tree mortality within burned area perimeters by 49%–89% between 2019 and 2021. Consistent with previous work, we found that tree mortality risk increased as a function of tree height. Tree mortality was positively associated with distance from rivers, trees per hectare, and decreasing slope at the lower elevation site. In contrast, increasing slope was positively associated with tree mortality at the higher elevation site. Our approach and dataset provide a means to study the combined effects of drought and wildfire on tree mortality and may improve projections of forest resilience under a changing climate. Plain Language Summary: Many trees died during the 2012–2016 California drought. Events like this could become more frequent as the climate warms. To understand the impact of the drought on California forests, we need to refine our estimates of tree death as new data become available. At two sites in the Sierra Nevada mountains, we used measurements of tree heights and high‐resolution reflectance data from aircraft to map out individual trees and identify when they died based on their shape and color. We mapped the location, height, and crown perimeter of more than 1 million trees, and we estimate that about one‐quarter of them died between 2013 and 2017. We found that taller trees, trees farther from rivers, and trees in dense stands were more likely to die, and these relationships were stronger at lower elevations. At lower elevations, shallower slopes were associated with more tree mortality, whereas steeper slopes were associated with higher mortality at higher elevations. Wildfires in 2020 and 2021 nearly doubled the number of dead trees within burned areas. Our study will help better predict when, where, and how trees die because of climate change. Key Points: We classified over 1 million trees as live or dead in the Sierra Nevada forests of California for five time points between 2013 and 2021Drought‐induced tree mortality was 25.4% between 2013 and 2017 and 2.0%–2.8% per year between 2017 and 2019Wildfires in 2020 and 2021 increased tree mortality by 49%–89% within burned area perimeters [ABSTRACT FROM AUTHOR]

The climate drives species distribution and genetic diversity; the latter defines the adaptability of populations and species. The ongoing climate crisis induces tree decline in many regions, compromising the mitigation potential of forests. Scientific‐based strategies for prioritizing forest tree populations are critical to managing the impact of climate change. Identifying future climate refugia, which are locations naturally buffering the negative impact of climate change, may facilitate local conservation. In this work, we conducted the populations' prioritization for Castanea sativa (sweet chestnut), a Neogene relict growing in the Caucasus global biodiversity hotspot. We generated genetic and ecological metrics for 21 sites in Georgia and Azerbaijan, which cover the natural range of sweet chestnut across the region. We demonstrated that climate primarily drives the pattern of genetic diversity in C. sativa, proved with a significant isolation‐by‐environment model. In future, climate change may significantly reorganize the species' genetic diversity, inducing even some genetic loss, especially in the very distinct eastern fringe of the species range in Azerbaijan. Based on our combined approach, we mapped populations suitable for ex situ and in situ conservation, accounting for genetic variability and the location of future climate refugia. [ABSTRACT FROM AUTHOR]

Monarch butterflies (Danaus plexippus) undergo an iconic multi‐generational migration, traveling thousands of kilometers from the summer breeding grounds in southern Canada to overwintering sites in central Mexico. This migration phenomena can be affected by climate change, which may have important implications on fitness and ultimately populations status. We investigated the long‐term trends in fall migration phenology of monarchs using a 25‐year dataset collected along the coast of Lake Erie in Ontario, Canada. We also investigated local long‐term trends in weather covariates that have the potential to influence migration phenology at this site. Patterns in standardized daily counts of monarchs were compared with local weather covariates using two methods (i.e., monthly averages and moving windows) to assess difference in outputs between analytical approaches. Our results suggest that monarch migration timing (migration midpoint, average peak, first peak, and late passage) and weather covariates have been consistent over time, in direct contrast to a similar study in Cape May, New Jersey, which showed a significant increase in both fall temperature and a 16‐ to 19‐day shift in monarch migration timing. Furthermore, our results differed between analytical approaches. With respect to annual variability in air temperature, our monthly average analysis suggested that for each degree increase in September air temperature, late season passage would advance 4.71 days (±1.59 SE, p =.01). However, the moving window analysis suggested that this result is likely spurious and found no significant correlations between migration timing and any weather covariates. Importantly, our results caution against extrapolating the effects of climate change on the migration phenology of the monarch across study regions and the need for more long‐term monitoring efforts to better understand regional drivers of variability in migration timing. [ABSTRACT FROM AUTHOR]