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It has been proposed that ectomycorrhizal (EcM) fungi slow down decomposition by competing with free-living saprotrophs for organic nutrients and other soil resources (known as the “Gadgil effect”), thereby increasing soil carbon sequestration. As such, this Gadgil effect should depend on soil organic matter age and quality, but this remains unstudied. In addition, the Gadgil effect is not expected to occur in arbuscular mycorrhizal (AM) forests since AM fungi cannot access directly nutrients from soil organic matter, yet few direct comparisons between EcM and AM forests have been made. We performed a two-year reciprocal decomposition experiment of soil organic horizons (litter—L, fragmented—F, humic—H) in adjacent temperate deciduous forests dominated by EcM or AM trees. Mesh bags were made of different mesh sizes allowing or excluding ingrowth of external fungal hyphae, which are primarily mycorrhizal in these forests other than for the most recent superficial litter horizon. As expected, EcM stands stored more soil carbon (up to 20 cm depth) than AM stands. Also, organic matter originating from deeper horizons and from EcM stands was of lower quality (for example, higher lignin to nitrogen ratios) and decomposed more slowly. However, contrary to the Gadgil effect, organic matter exposed to external fungal hyphae (that is, primarily mycorrhizal) actually decomposed faster in both forest types, and this effect was strongest in EcM forests, particularly in the F horizon. Unexpectedly, organic matter decomposition was faster in EcM than in AM forests, regardless of organic matter origin. Overall, our study reinforces the view that temperate EcM forests store greater amounts of soil organic carbon than AM forests, but suggests that this is due to factors other than the Gadgil effect.

The study of animal–habitat interactions is of primary importance for the formulation of conservation recommendations. Flying, gliding, and climbing animals have the ability to exploit their habitat in a three‐dimensional way, and the vertical canopy structure in forests plays an essential role for habitat suitability. Forest bats as flying mammals may seasonally shift their microhabitat use due to differing energy demands or changing prey availability, but the patterns are not well understood. We investigated three‐dimensional and seasonal habitat use by insectivorous bats in a temperate lowland old‐growth forest, the Belovezhskaya Pushcha in Belarus. We acoustically sampled broadleaved and mixed coniferous plots in the forest interior and in gaps in three heights during two reproductive periods (pregnancy/lactation vs. postlactation). In canopy gaps, vertical stratification in bat activity was less pronounced than in the forest interior. Vertical activity patterns differed among species. The upper canopy levels were important foraging habitats for the open‐space forager guild and for some edge‐space foragers like the Barbastelle bat Barbastella barbastellus and the soprano pipistrelle Pipistrellus pygmaeus. Myotis species had highest activity levels near the ground in forest gaps. Moreover, we found species‐dependent seasonal microhabitat shifts. Generally, all species and species groups considered except Myotis species showed higher activity levels during postlactation. Myotis species tended toward higher activity in the forest interior during postlactation. P. pygmaeus switched from high activity levels in the upper canopy during pregnancy and lactation to high activity levels near the ground during postlactation. We conclude that a full comprehension of forest bat habitat use is only possible when height in canopy and seasonal patterns are considered., We investigated three‐dimensional and seasonal habitat use by insectivorous bats in a temperate lowland old‐growth forest. We identified guild‐ and species‐specific differences in canopy height use and species‐dependent seasonal microhabitat shifts that can be explained by ecomorphological adaptations.

Global change impacts marine organisms and communities mainly through ocean warming, acidification, deoxygenation, and changes in nutrient inputs and water circulation. To assess the ecological impacts of global change, the effects of multiple interacting environmental drivers, including their fluctuations, should be tested at different levels of biological organization. In an outdoor mesocosm study, we investigated the differential effects of three simulated upwelling events coupled with ocean warming (1–5°C above ambient) on a temperate benthic community in the Western Baltic Sea. Ocean warming, especially in summer when temperatures are close to or above the physiological optimum of many species, is likely to impose thermal stress with species-specific impacts. As the properties of deep water vary seasonally, so will the effects of upwelling. Upwelling of cooler deep water in midsummer may alleviate thermal stress, although this mitigation may be modulated by upwelling-associated shifts in other water-quality parameters such as salinity, nutrients, or late-summer hypoxia. This investigation showed that in the Western Baltic Ocean warming was rather beneficial in early and late summer but detrimental when ambient temperatures were highest in midsummer. The effects of upwelling in the absence of ocean warming were generally weakly beneficial, while this effect tended to vanish with intensifying imposed ocean warming. Hypoxia associated with the late summer upwelling impacted some of the grazer species but did not impact the macroalgae. We conclude that in coastal temperate benthic communities, ocean warming is the predominant stressor that may partially and seasonally be buffered by upwelling.

Plant–mycorrhizal interactions mediate plant nitrogen (N) limitation and can inform model projections of the duration and strength of the effect of increasing CO2 on plant growth. We present dendrochronological evidence of a positive, but context-dependent fertilization response of Quercus rubra L. to increasing ambient CO2 (iCO2) along a natural soil nutrient gradient in a mature temperate forest. We investigated this heterogeneous response by linking metagenomic measurements of ectomycorrhizal (ECM) fungal N-foraging traits and dendrochronological models of plant uptake of inorganic N and N bound in soil organic matter (N-SOM). N-SOM putatively enhanced tree growth under conditions of low inorganic N availability, soil conditions where ECM fungal communities possessed greater genomic potential to decay SOM and obtain N-SOM. These trees were fertilized by 38 years of iCO2. In contrast, trees occupying inorganic N rich soils hosted ECM fungal communities with reduced SOM decay capacity and exhibited neutral growth responses to iCO2. This study elucidates how the distribution of N-foraging traits among ECM fungal communities govern tree access to N-SOM and subsequent growth responses to iCO2. Root-mycorrhizal interactions could help explain the heterogeneity of plant responses to CO2 fertilisation and nutrient availability. Here the authors combine tree-ring and metagenomic data to reveal that tree growth responses to increasing CO2 along a soil nutrient gradient depend on the nitrogen foraging traits of ectomycorrhizal fungi.

As the climate warms, endotherms are challenged with maintaining body temperature within a neutral range. Modifying behaviour to mitigate heat loads is a potentially low-cost response to avoid heat stress and may be critical to persistence in a changing environment, especially for large endotherms. We tested the hypothesis that bed sites are a thermal refuge and means of behavioural mitigation of heat loads for a large temperate ungulate especially prone to heat stress, the Shiras moose, Alces alces shirasi. We predicted that if bed sites are a thermal refuge, selection of bed sites should be consistent with sites that reduce heat gain or increase heat loss via convection or conduction. Moose selected cool bed sites with a substrate that was moist, wet or had standing water, and avoided bedding in open or sparse vegetation. On warm days and during the warmest periods of the day, moose increased selection for wet substrate and for bed sites in standing water with sparse vegetation, which they avoided on cool days and during cool periods of the day. Strong and context-dependent selection for bed sites that would reduce heat gain and ameliorate heat load supports the notion that bed sites are a thermal refuge and a way to behaviourally mitigate warming temperatures. Flexibility in habitat selection may be a primary way for large endotherms to combat a warming climate, although doing so is contingent on habitat assemblages that offer thermal refuge to limit heat gain and importantly, facilitate heat loss.

Background and Aims Carbon reserves are a critical source of energy and substrates that allow trees to cope with periods of minimal carbon gain and/or high carbon demands, conditions which are prevalent in high-latitude forests. However, we have a poor understanding of carbon reserve dynamics at the whole-tree level in mature boreal trees. We therefore sought to quantify the seasonal changes in whole-tree and organ-level carbon reserve pools in mature boreal Betula papyrifera. Methods Non-structural carbohydrate (NSC; soluble sugars and starch) tissue concentrations were measured at key phenological stages throughout a calendar year in the roots, stem (inner bark and xylem), branches and leaves, and scaled up to estimate changes in organ and whole-tree NSC pool sizes. Fine root and stem growth were also measured to compare the timing of growth processes with changes in NSC pools. Key Results The whole-tree NSC pool increased from its spring minimum to its maximum at bud set, producing an average seasonal fluctuation of 0.96 kg per tree. This fluctuation represents a 72 % change in the whole-tree NSC pool, which greatly exceeds the relative change reported for more temperate conspecifics. At the organ level, branches accounted for roughly 48–60 % of the whole-tree NSC pool throughout the year, and their seasonal fluctuation was four to eight times greater than that observed in the stemwood, coarse roots and inner bark. Conclusions Branches in boreal B. papyrifera were the largest and most dynamic storage pool, suggesting that storage changes at the branch level largely drive whole-tree storage dynamics in these trees. The greater whole-tree seasonal NSC fluctuation in boreal vs. temperate B. papyrifera may result from (1) higher soluble sugar concentration requirements in branches for frost protection, and/or (2) a larger reliance on reserves to fuel new leaf and shoot growth in the spring.

Summary The soil pathogen‐induced Janzen–Connell (JC) effect is considered as a primary mechanism regulating plant biodiversity worldwide. As predicted by the framework of the classic plant disease triangle, severity of plant diseases is often influenced by temperature, yet insufficient understanding of how increasing temperatures affect the JC effect contributes uncertainty in predictions about how global warming affects biodiversity.We conducted a 3‐yr field warming experiment, combining open‐top chambers with pesticide treatment, to test the effect of elevated temperatures on seedling mortality of a temperate tree species, Prunus padus, from a genus with known susceptibility to soil‐borne pathogens.Elevated temperature significantly increased the mortality of P. padus seedlings in the immediate vicinity of parent trees, concurrent with increased relative abundance of pathogenic fungi identified to be virulent to Prunus species.Our study offers experimental evidence suggesting that global warming significantly intensifies the JC effect on a temperate tree species due to increased relative abundance of pathogenic fungi. This work advances our understanding about changes in the JC effect linked to ongoing global warming, which has important implications for predicting tree diversity in a warmer future.

Silicon (Si) accumulation is known to alleviate various biotic and abiotic stressors in plants with potential ecological consequences. However, for dicotyledonous plants our understanding of Si variation remains limited. We conducted a comparative experimental study to investigate (1) interspecific variation of foliar Si concentrations across 37 dicotyledonous forbs of temperate grasslands, (2) intraspecific variation in foliar Si concentration in response to soil Si availability, the influence of (3) phylogenetic relatedness, and (4) habitat association to moisture. Foliar Si differed markedly (approx. 70-fold) across the investigated forbs, with some species exhibiting Si accumulation similar to grasses. Foliar Si increased with soil Si availability, but the response varied across species: species with higher Si accumulation capacity showed a stronger response, indicating that they did not actively upregulate Si uptake under low soil Si availability. Foliar Si showed a pronounced phylogenetic signal, i.e., closely related species exhibited more similar foliar Si concentrations than distantly related species. Significant differences in foliar Si concentration within closely related species pairs nevertheless support that active Si uptake and associated high Si concentrations has evolved multiple times in forbs. Foliar Si was not higher in species associated with drier habitats, implying that in dicotyledonous forbs of temperate grasslands high foliar Si is not an adaptive trait to withstand drought. Our results demonstrated considerable inter- and intraspecific variation in foliar Si concentration in temperate forbs. This variation should have pervasive, but so far understudied, ecological consequences for community composition and functioning of temperate grasslands under land-use and climate change. Supplementary Information The online version contains supplementary material available at 10.1007/s00442-021-04978-9.

This study aimed at investigating the influence of different postharvest treatments with oxalic acid (OA) and salicylic acid (SA) on quality attributes and postharvest shelf life of temperate grown apricot varieties stored under controlled atmosphere (CA) storage conditions. After each treatment was given, the samples were stored in CA store maintained at a temperature of 0 °C, 90 ± 5% relative humidity, 5% oxygen and 15% carbon dioxide for 30 days. Results indicated that both OA and SA treatments significantly (p ≤ 0.05) retained total soluble solids, titratable acidity, color profile, ascorbic acid content and total phenolic content of apricot varieties and had a positive effect on antioxidant activity and texture of samples compared to control. However, carotenoid content was found to be higher in control. Both the treatments reduced chilling injury index, weight loss and decay percentage of samples. Moreover, it was found that SA treatment was the most effective treatment in maintaining visual color of apricots while OA maintained fruit firmness and effectively decreased the decay percentage and chilling injury index of apricot varieties. In conclusion, it was found that both OA and SA have the potential to extend storage life of apricots and maintain quality attributes of the crop during CA storage.

To study the effects of a typhoon on a temperate, coastal bay community, the species composition, catch amount, and diversity of epipelagic fish assemblages were investigated. Fish samples were taken from catches of a purse seine fishery in Tachibana Bay, Japan between May and July 2011, covering before and after the passage of a typhoon in the area. Although major changes in total catch amount were not observed before and after the passage of the typhoon, the abundance of the Japanese anchovy, Engraulis japonicus Temminck et Schlegel, 1846, markedly decreased and bycatch of species increased, accompanied by increasing levels of diversity of the fish assemblage. Multivariate analysis showed that community differences before and after the passage were quantitative rather than qualitative. Comparisons in total length frequencies between the two periods indicated that specimens of the species compared were bigger in size for Trachurus japonicus (Temminck et Schlegel, 1844) and smaller for E. japonicus in the “after” period. These results suggest that the passage of the typhoon triggered not only interspecific faunal change but also intraspecific recruitment shifts in and around the bay., Acta Ichthyologica et Piscatoria, 51(2), pp. 175-183; 2021

Temperate mixedwoods (hardwood–softwood mixtures) in central and eastern United States and Canada can be classified into two overarching categories: those with shade-tolerant softwoods maintained by light to moderate disturbances and those with shade-intolerant to mid-tolerant softwoods maintained by moderate to severe disturbances. The former includes red spruce (Picea rubens Sarg.), balsam fir (Abies balsamea (L.) Mill.), or eastern hemlock (Tsuga canadensis (L.) Carr.) in mixture with northern hardwood species; the latter includes pine (Pinus) – oak (Quercus) mixtures. Such forests have desirable socio-economic values, wildlife habitat potential, and (or) adaptive capacity, but management is challenging because one or more softwood species in each can be limited by depleted seed sources, narrow regeneration requirements, or poor competitive ability. Appropriate silvicultural systems vary among mixedwood compositions depending on shade tolerance and severity of disturbance associated with the limiting softwoods, site quality, and level of herbivory. Sustainability of mixedwood composition requires that stand structure and composition be managed at each entry to maintain vigorous trees of species with different growth rates and longevities and to encourage development of advance reproduction or seed-producing trees of desired species. Regardless of silvicultural system, maintaining seed sources of limiting softwoods, providing suitable germination substrates, and controlling competition are critical. Here, we describe commonalities among temperate mixedwoods in central and eastern North America and present a framework for managing them.

Accurate biodiversity and population monitoring is a requirement for effective conservation decision making. Survey method bias is therefore a concern, particularly when research programs face logistical and cost limitations.We employed point counts (PCs) and autonomous recording units (ARUs) to survey avian biodiversity within comparable, high elevation, temperate mountain habitats at opposite ends of the Americas: nine mountains in British Columbia (BC), Canada, and 10 in southern Chile. We compared detected species richness against multiyear species inventories and examined method‐specific detection probability by family. By incorporating time costs, we assessed the performance and efficiency of single versus combined methods.Species accumulation curves indicate ARUs can capture ~93% of species present in BC but only ~58% in Chile, despite Chilean mountain communities being less diverse. The avian community, rather than landscape composition, appears to drive this dramatic difference. Chilean communities contain less‐vocal species, which ARUs missed. Further, 6/13 families in BC were better detected by ARUs, while 11/11 families in Chile were better detected by PCs. Where survey conditions differentially impacted method performance, PCs mostly varied over the morning and with canopy cover in BC, while ARUs mostly varied seasonally in Chile. Within a single year of monitoring, neither method alone was predicted to capture the full avian community, with the exception of ARUs in the alpine and subalpine of BC. PCs contributed little to detected diversity in BC, but including this method resulted in negligible increases in total time costs. Combining PCs with ARUs in Chile significantly increased species detections, again, for little cost.Combined methods were among the most efficient and accurate approaches to capturing diversity. We recommend conducting point counts, while ARUs are being deployed and retrieved in order to capture additional diversity with minimal additional effort and to flag methodological biases using a comparative framework., Using avian surveys conducted in comparable, high elevation, temperate mountain habitats at opposite ends of the Americas (British Columbia, Canada, and southern Chile), we show combined ARU and point count methods are among the most efficient and accurate approaches to capturing diversity. ARUs were predicted to capture ~93% of species present in British Columbia but only ~58% in Chile, despite Chilean mountain communities being less diverse. The use of combined methods enable studies to flag methodological biases using a comparative framework.

Phenological responses of plants to temperature dynamics are receiving attention due to the ongoing challenge with climate change. Most previous phenological studies have focused on flowering phenology rather than fruiting phenology. However, at mid-latitudes, the air temperature periodically changes during the growing period of plants. Hence, cool temperatures early and late in the growing period may affect reproductive success through pollination and fruit-development processes. To evaluate the linkages between reproductive phenology and success, we compared the phenologies, photosynthetic capacities, and fruit-set rates among 25 species within a cool-temperate community in northern Japan. The ambient temperature during the flowering periods of individual species increased with delays in flowering-onset time, whereas the ambient temperature during fruit-development periods was highest for species which bloomed in July. Fruit-set success among species was positively correlated with the ambient temperatures during the reproductive periods and with the photosynthetic capacity. Fruit production of early blooming species was limited by cool temperatures during the flowering period, presumably because of low pollinator activity, whereas that of late-blooming species was limited by cool temperatures during the fruit-development period because of slow fruit-development (i.e., sink limitation). Thus, limiting factors of fruit production varied depending on the flowering phenology of individual species within a community.

Temperate organisms are generally exposed to a more variable and cooler climate than tropical organisms, and are therefore expected to have broader thermal tolerance and a different thermal performance curve. This study investigated these hypotheses by comparing the thermal performance of two common tropical coral species found in the Great Barrier Reef with the two most common temperate coral species from the Mediterranean Sea. Photosynthesis rates, dark respiration rates, maximum PSII quantum yield (Fv/Fm) and electron transport rates (rETRm) were measured on coral fragments exposed to an acute temperature increase and decrease up to 5 °C above and below the average environmental seawater temperature. Dark respiration rates and Fv/Fm increased linearly with temperature, suggesting broad thermal tolerance. For photosynthesis and rETRm, the performance breadths were surprisingly similar between the tropical and temperate species. However, the thermal optimum for performance was generally below the local average temperature, and only coincided with the prevailing environmental temperature for one of the tropical species. The broad thermal tolerance for photosynthesis displayed in this study supports previous observations that corals can survive short periods of abnormally warm temperatures and suggests that corals adopt thermal generalist strategies to cope with temperature variation in the environment. Nevertheless, current mean temperatures are 10–30% above the thermal optimum for the species studied here, demonstrating that conditions are already pushing the boundaries of coral thermal tolerance.

Marine wood-boring invertebrates rapidly fragment coarse woody debris in the sea. These wood borers have the ability to digest wood cellulose, but other potential food sources have been less investigated. To assess the contribution of each potential food source to the diet of wood borers, we traced seasonal and environmental changes in δ13C of shipworms cultured under the same experimental conditions and related these changes to variations in δ13C of potential food sources, i.e., wood log and particulate organic matter (POM) by using multiple linear regression models rather than the Bayesian mixing model. Based on the standardized partial regression coefficients in the model, it became clear that wood-derived organic carbon was the main carbon source for the teredinids, and POM also accounted for 37.9% of the teredinids' carbon source. Furthermore, we clarified variations in supplemental nitrogen sources for the teredinids: one species depended on both POM and wood log, whereas the other three species depended on either POM or wood log for their nitrogen source. δ13C values of another wood-boring bivalve of Martesia (Pholadidae) increase as it grows, which suggests that the bivalve switches its feeding strategy from xylophagous to filter feeding as it grows. Wood borers are known to accelerate the transfer of organic materials derived from wood logs to marine ecosystems. However, this study suggests that autochthonous production strongly contribute to the diet of marine wood borers, helping them to decompose wood logs in temperate shallow water.

Resting bud cataphylls are often assumed to play an essential protective role in winter due to their widespread presence among temperate, woody plants. This view is challenged by our documentation of significant numbers of temperate woody angiosperm taxa with naked buds that overwinter without cataphyll protection. We inventoried temperate, woody angiosperm taxa reported to have resting buds without cataphyll protection in winter and for the first time characterised the morphological and functional diversity of naked buds. Using this new classification of bud types, the taxonomic and geographic distributions of taxa with naked buds were summarised and relationships between plant functional traits and bud type were investigated. Naked buds are not, as long presumed, markedly rare in temperate, woody floras. They occur in at least 87 genera in 42 families throughout the angiosperm phylogeny in various morphologically distinct manifestations. The geographic distribution of species with naked buds in temperate areas was found to be associated with summer precipitation, but not with winter climatic variables. Resting bud structure is not necessarily a trait optimised solely for winter survival. A taxon's bud composition may be influenced by factors such as biogeographic history and ontogenetic pattern of leaf formation over the growing season.

Climate change is rapidly altering the distributions of species and the composition of communities that have evolved over evolutionary time scales. Quantifying changes in species distributions and abundance in response to warming is critical to understanding how these changes modify structure, function and services provided by recipient communities. Changes in size structure of warm- and cool-affiliated species is an important indicator for climate-driven species redistributions over time, and has received relatively little attention. We quantified changes in length and biomass distributions of 25 species of Labridae fishes from 112 sites spanning 2000 km across a warm-cool temperate transition zone in south Western Australia. Length and biomass data were collected in 2005-2006 and 2014-2015 using diver operated stereo-video. In the decade between sampling events, south Western Australia experienced an extreme marine heatwave followed by repeated summers of anomalously warm ocean temperatures. Biomass of tropical and subtropical species increased 10-fold and 3-fold, respectively, between 2006 and 2015, whereas temperate species biomass remained relatively stable. In 2014-2015, the abundance and biomass of tropical species (e.g. Scarus ghobban) increased in the warmest regions and established multiple size classes poleward of their recorded 2005-2006 distributions, suggesting successful overwintering and recruitment where viable populations were not recorded in 2005-2006. Large, slow-growing temperate species such as Achoerodus gouldii and Bodianus frenchii decreased in small and medium size classes in warm regions. Our findings report a substantial change in the size structure and composition of labrid assemblages over a decade of climatic variability.

The composition of nonnative floras is influenced by a region’s socioeconomic history, yet rarely are these factors studied alongside plant naturalization rates over time. Such information is especially critical for archipelagos, which often host large numbers of nonnative plants and would benefit from prevention of inter-island spread. We compiled the first record of occurrence and first record of naturalization for all naturalized plants in Hawai‘i alongside data on their origin, native climate types, taxonomy, and likely introduction pathway and compared rates of naturalization with socioeconomic trends. We found that the rate of total plant naturalizations has increased at a roughly constant rate during the past century without any sign of plateauing. However, this relatively steady increase is underlain by notable fluctuations in naturalization rates for different introduction pathways, with ornamentals increasing recently, while agriculture-related plants have decreased. Furthermore, this trend mirrors a shift from an agriculture-dominated economy to a tourism-based one associated with increases in both resident and tourist populations as well as general economic well-being. We further found that the average naturalized species spreads at a rate of 1.86 islands per decade, eventually occupying most major islands in the archipelago, and the rate of spread appears to be increasing since Hawai‘i’s economic shift. Our findings also emphasize the diversity of Hawai‘i’s nonnative flora, which originates from a variety of climates, continents, and taxonomic groups. We demonstrated that many nonnative species have native ranges that include temperate climates, which is important, because these climates typically co-occur with higher-elevation, remnant patches of native-dominated ecosystems in Hawai‘i. This study reveals trends that may help predict a species’ ability to naturalize and spread within and between islands, and we discuss management implications that may be extended to other regions.

We use an Australian freshwater invertebrate species, Daphnia carinata, to assess whether variation in habitat permanence influences life-history traits in subpopulations. Using a life table experiment, we measure the life-history traits of populations from both permanent and temporary pools. We show that these habitat classes are associated with clear differences in important life-history traits and evidence of trade-offs in important traits influencing reproduction, diapause, and growth rate and suggest this is evidence for local adaptation. Here we use Daphnia from Australian populations spanning semi-arid and temperate climates generating results that are in broad agreement with similar studies in the northern hemisphere, and so extend these results to a new continent and its particular climate. Variation in habitat permanence, it appears, is a very general driver of life-history divergence.

Perennial pastures are the dominant feedbase in many regions of the world, and offer several advantages when compared with an annual pasture system. In Western Australia (WA) there has been a concerted effort over seven decades to develop new perennial pasture options and expand the adoption of suitable species. The agricultural region of WA (i.e. south-western Australia) is characterised by a Mediterranean climate where the 5–7 month summer drought has proved a considerable challenge with only a small number of the many promising species being adopted commercially. Research, development, and extension have covered a wide range of herbaceous perennial legumes, leguminous and native shrubs, herbs, and temperate and warm season grasses. This paper reviews the literature to determine whether a perennial pasture must satisfy the following criteria to be successful and widely adopted in south-western Australia: (i) sourced from a similar Mediterranean environment and adapted to the target soils; (ii) have a relative advantage over the annual-based system it replaces; (iii) a robust management package; and (iv) a viable seed supply. The findings of this review highlight that perennial pastures must indeed satisfy multiple criteria to be commercially successful. Notably, the requirement for the source of the germplasm to have a good match between climate and soils is less clear because some of the commercially successful species come from diverse environments. We conclude with some key learnings for future perennial pasture development as climate change intensifies the research challenge and the drive for producers to adapt.

Phenological escape, a strategy that deciduous understory plants use to access direct light in spring by leafing out before the canopy closes, plays an important role in shaping the recruitment of temperate tree seedlings. Previous studies have investigated how climate change will alter these dynamics for herbaceous species, but there is a knowledge gap related to how woody species such as tree seedlings will be affected. Here, we modeled temperate tree seedling leaf-out phenology and canopy close phenology in response to environmental drivers and used climate change projections to forecast changes to the duration of spring phenological escape. We then used these predictions to estimate changes in annual carbon assimilation while accounting for reduced carbon assimilation rates associated with hotter and drier summers. Lastly, we applied these estimates to previously published models of seedling growth and survival to investigate the net effect on seedling demographic performance. Our models predict that temperate tree seedlings will experience improved phenological escape and, therefore, increased spring carbon assimilation under climate change conditions. However, increased summer respiration costs will offset the gains in spring under extreme climate change leading to a net loss in annual carbon assimilation and demographic performance. Furthermore, we found that annual carbon assimilation predictions depend strongly on the species of nearby canopy tree that seedlings were planted near, with all seedlings projected to assimilate less carbon (and therefore experience worse demographic performance) when planted near Quercus rubra canopy trees as opposed to Acer saccharum canopy trees. We conclude that changes to spring phenological escape will have important effects on how tree seedling recruitment is affected by climate change, with the magnitude of these effects dependent upon climate change severity and biological interactions with neighboring adults. Thus, future studies of temperate forest recruitment should account for phenological escape dynamics in their models.

In temperate monsoon climate zones, which feature low precipitation in winter and spring, summer planting of Pinus tabuliformis Carr. seedlings may improve site restoration. The application of moderate water stress to improve seedling drought resistance may be an option to harden summer-plant seedlings. The objective of this study was to assess the effect of watering intensity and duration of acclimation treatments on seedling morphology and physiology attributes in the nursery and on the field performance of Pinus tabuliformis. We applied three watering intensities at 45%, 60%, 75% (control) of container capacity (CC) in the nursery for three durations (2, 3 and 4 weeks) during early summer and then correspondingly outplanted in three dates across July (i.e., 11th, 18th, and 27th). We measured seedling morphology, non-structural carbohydrates (TNC) and nitrogen (N) concentrations in the nursery, and in the field. Additionally, we measured field mortality and plant growth for three years. Drought hardening led to greater bud set and TNC reserves, along with lower shoot-to-root mass ratio (S/R). Longer drought hardening duration produced seedlings with larger stem volume, lower S/R and lower N concentration, but with greater root mass and bud set. Field mortality primarily occurred in the winter, with the three-week drought hardening causing increased winter mortality but enhanced field growth. Mortality during the first winter was negatively related to shoot TNC reserves but positively related to seedling field growth measured at the beginning of the fall, cold season. Mortality during the second winter was negatively related to seedling size but positively related to S/R measured at the end of second growing season. In contrast, drought hardening intensity had no effect on outplanting mortality and only a minor effect on field growth. Field growth in subsequent growing seasons was directly related to the size of the plant, N and TNC content at the beginning of the first fall cold season. This study demonstrates that higher TNC reserves were associated with smaller stem volume during the first growing season, suggesting a trade-off between growth and TNC storage. This suggests that under non-stressed conditions the TNC concentration and growth of seedlings before winter strongly affected their mortality during winter. Study results suggest that summer planting of P. tabuliformis container seedlings is feasible without the application of drought hardening acclimation treatments in geographic locations typically having summer rains. Optimizing the outplanting date during the summer and initial seedling size appear to be critical for good mid-term growth and low winter mortality.

Tropical ectotherm species tend to have narrower physiological limits than species from temperate areas. As a consequence, tropical species are considered highly vulnerable to climate change since minor temperature increases can push them beyond their physiological thermal tolerance. Differences in physiological tolerances can also be seen at finer evolutionary scales, such as among populations of ectotherm species along elevation gradients, highlighting the physiological sensitivity of such organisms.Here, we analyze the influence of elevation and bioclimatic domains, defined by temperature and precipitation, on thermal sensitivities of a terrestrial direct‐developing frog (Craugastor loki) in a tropical gradient. We address the following questions: (a) Does preferred temperature vary with elevation and among bioclimatic domains? (b) Do thermal tolerance limits, that is, critical thermal maximum and critical thermal minimum vary with elevation and bioclimatic domains? and (c) Are populations from high elevations more vulnerable to climate warming?We found that along an elevation gradient body temperature decreases as environmental temperature increases. The preferred temperature tends to moderately increase with elevation within the sampled bioclimatic domains. Our results indicate that the ideal thermal landscape for this species is located at midelevations, where the thermal accuracy (db) and thermal quality of the environment (de) are suitable. The critical thermal maximum is variable across elevations and among the bioclimatic domains, decreasing as elevation increases. Conversely, the critical thermal minimum is not as variable as the critical thermal maximum.Populations from the lowlands may be more vulnerable to future increases in temperature. We highlight that the critical thermal maximum is related to high temperatures exhibited across the elevation gradient and within each bioclimatic domain; therefore, it is a response to high environmental temperatures., Our study shows how the physiological thermal traits on a finer scale are shaped by heterogeneity environmental of the frogs of genus Craugastor. We measured different ecophysiological thermal traits in 15 populations along an elevation gradient and five bioclimatic landscapes and estimated the warming tolerance and cooling tolerance of the frogs. We highlight that the critical thermal limit maximum is a response to high environmental temperatures, suggesting the role of thermal plasticity is expressed in response to variation in environmental temperature. The results contribute to the understanding how resilience is critical in a warming world.

Vegetation optical depth (VOD) from microwave satellite observations has received much attention in global vegetation studies in recent years due to its relationship to vegetation water content and biomass. We recently have shown that VOD is related to plant productivity, i.e., gross primary production (GPP). Based on this relationship between VOD and GPP, we developed a theory-based machine learning model to estimate global patterns of GPP from passive microwave VOD retrievals. The VOD-GPP model generally showed good agreement with site observations and other global data sets in temporal dynamic but tended to overestimate annual GPP across all latitudes. We hypothesized that the reason for the overestimation is the missing effect of temperature on autotrophic respiration in the theory-based machine learning model. Here we aim to further assess and enhance the robustness of the VOD-GPP model by including the effect of temperature on autotrophic respiration within the machine learning approach and by assessing the interannual variability of the model results with respect to water availability. We used X-band VOD from the VOD Climate Archive (VODCA) data set for estimating GPP and used global state-of-the-art GPP data sets from FLUXCOM and MODIS to assess residuals of the VOD-GPP model with respect to drought conditions as quantified by the Standardized Precipitation and Evaporation Index (SPEI). Our results reveal an improvement in model performance for correlation when including the temperature dependency of autotrophic respiration (average correlation increase of 0.18). This improvement in temporal dynamic is larger for temperate and cold regions than for the tropics. For unbiased root-mean-square error (ubRMSE) and bias, the results are regionally diverse and are compensated in the global average. Improvements are observed in temperate and cold regions, while decreases in performance are obtained mainly in the tropics. The overall improvement when adding temperature was less than expected and thus may only partly explain previously observed differences between the global GPP data sets. On interannual timescales, estimates of the VOD-GPP model agree well with GPP from FLUXCOM and MODIS. We further find that the residuals between VOD-based GPP estimates and the other data sets do not significantly correlate with SPEI, which demonstrates that the VOD-GPP model can capture responses of GPP to water availability even without including additional information on precipitation, soil moisture or evapotranspiration. Exceptions from this rule were found in some regions: significant negative correlations between VOD-GPP residuals and SPEI were observed in the US corn belt, Argentina, eastern Europe, Russia and China, while significant positive correlations were obtained in South America, Africa and Australia. In these regions, the significant correlations may indicate different plant strategies for dealing with variations in water availability. Overall, our findings support the robustness of global microwave-derived estimates of gross primary production for large-scale studies on climate–vegetation interactions.

We tested the hypothesis that interspecific variation in chiropteran heat tolerance and evaporative cooling capacity is correlated with day-roost microclimates, using three vespertilionid bats that occur sympatrically during summer in Saskatchewan, Canada. We predicted that hoary bats (Lasiurus cinereus (Palisot de Beauvois, 1796); ∼22 g) would have higher heat tolerance than little brown bats (Myotis lucifugus (Le Conte, 1831); ∼7 g) and silver-haired bats (Lasionycteris noctivagans (Le Conte, 1831); ∼13 g), as the latter two species roost in tree crevices or cavities that are more thermally buffered than the foliage roosts of hoary bats. We measured core body temperature (Tb; passive integrated transponder tags), evaporative water loss, and resting metabolic rate (flow-through respirometry) while exposing individuals to a stepped profile of increasing air temperature (Ta) from ∼30 °C in ∼2 °C increments. Experiments were terminated when individuals became hyperthermic (Tb ≈ 42.5 °C), with maximum Ta (Ta,max) ranging from 42.0 to 49.7 °C. As predicted, hoary bats had the highest heat tolerance and evaporative cooling capacity, reaching Ta,max ∼2.4 and 1.2 °C higher than little brown and silver-haired bats, respectively. Our results are consistent with the hypothesis that heat tolerance of bats is correlated with roost microclimates, although interspecific variation in body mass and phylogeny may confound these conclusions.

From regional to global scales, anthropogenic environmental change is causing biodiversity loss and reducing ecosystem functionality. Previous studies have investigated the relationship between plant diversity and functional insect communities in temperate and also in tropical grasslands and forests. However, few studies have explored these dynamics in subtropical forests. Here, cavity-nesting Hymenoptera and associated parasitoids were collected across a controlled tree diversity experiment in subtropical China to test how predatory wasps, bees and parasitoids respond to tree species richness. Abundance and species richness of predatory wasps and parasitoids were positively correlated with tree species richness, while bee abundance and bee species richness were unrelated to tree species richness. Our results indicate that tree species richness increases the abundance and species richness of important communities such as predators and parasitoids. Moreover, the results highlight the importance of subtropical forests in maintaining abundance and species richness of key functional insect groups.

Global environmental changes have strongly affected forest demographic rates, particularly amplified tree mortality in high latitude forests (e.g., two to five times greater mortality probability over the half-century). Although forest functional composition is critical for multitrophic biodiversity and ecosystem functioning, it remains unclear how functional composition has changed over time across large high latitude regions, which have been warming twice the rate of the globe as a whole. Using extensive spatial and long-term forest inventory data (17,107 plots monitored 1951-2016) across Canada, we found that after accounting for stand age-dependent functional shifts, functional composition shifted toward fast-growing deciduous broadleaved trees and higher drought tolerance over time. The temporal shift toward deciduous broadleaved trees was consistent across the baseline climate. However, over the study period, drought tolerance increased (or shade tolerance decreased) by 300% in colder boreal regions, while drought tolerance did not shift significantly in warmer temperate climates. A further analysis accounting for temporal changes in atmospheric CO2 , temperature, and water availability indicated that the functional composition of colder regions shifted toward drought tolerance more rapidly with rising CO2 than warmer regions, suggesting the greater vulnerability of boreal forests than temperate forests under ongoing global environmental changes. Future ecosystem management practices should consider spatial differences in functional responses to global environmental change, focusing on high latitude forests experiencing higher rates of warming and compositional changes.

Anthropogenic nitrogen (N) input is known to alter plant and microbial α-diversity, but how N enrichment influences β-diversity of plant and microbial communities remains poorly understood. Using a long-term multilevel N addition experiment in a temperate steppe, we show that plant, soil bacterial and fungal communities exhibited different responses in their β-diversity to N input. Plant β-diversity decreased linearly as N addition increased, as a result of increased directional environmental filtering, where soil environmental properties largely explained variation in plant β-diversity. Soil bacterial β-diversity first increased then decreased with increasing N input, which was best explained by corresponding changes in soil environmental heterogeneity. Soil fungal β-diversity, however, remained largely unchanged across the N gradient, with plant β-diversity, soil environmental properties, and heterogeneity together explaining an insignificant fraction of variation in fungal β-diversity, reflecting the importance of stochastic community assembly. Our study demonstrates the divergent effect of N enrichment on the assembly of plant, soil bacterial and fungal communities, emphasizing the need to examine closely associated fundamental components (i.e., plants and microorganisms) of ecosystems to gain a more complete understanding of ecological consequences of anthropogenic N enrichment.

Fungi are essential in aquatic ecosystems, transforming organic matter into energy sources that support higher trophic levels. However, researchers do not yet know the extent of fungal diversity and species distribution within these important ecosystems. Therefore, we examined the detrital fungal communities from contrasting aquatic habitats (temperate peatlands and streams) to provide an in-depth inventory and greater understanding of how these communities differ. Fine submerged detritus or substrate on or beneath the stream bed were collected from 6 sites. Fungal cultures were isolated from samples collected in May, July/August, and November from 2 sites in 2014 and 4 sites in 2016. Culture-independent analyses were conducted on 42 environmental samples collected in November 2016. Results indicated that peatland and stream fungal communities were taxonomically diverse, phylogenetically distinct, and harbored many unknown taxa from the kingdom Fungi. Specifically, stream habitats were more species-rich, in both number of species and phylogenetic diversity, compared to peatland habitats. In addition, fungal species and phylogenetic distribution within most major fungal classes were distinct between peatland and stream fungal communities. In light of global climate change, habitat loss, and water pollution, it has become increasingly important to examine these understudied and essential fungal communities within these ecosystems.

Sediment oxygen demand (SOD) and hypolimnetic oxygen demand (HOD) drive deep-water dissolved oxygen (DO) depletion in lakes, yet these parameters can be difficult to be measure routinely. To addres...

Mistletoes are emerging as important co-contributors to tree mortality across terrestrial ecosystems, particularly when infected trees are stressed by water limitations during drought. While the mechanistic effects of mistletoe infection on host physiology are reasonably well understood, quantifying the effects of mistletoe infection on stand productivity, canopy turnover and ecosystem structure remains challenging. Moreover, the potential devastating effect of mistletoe infection on host survival has distracted from the challenges that mistletoe populations are facing when increasing drought and heat stress threaten their survival in healthy populations. We coupled intensive observations of mistletoe population dynamics with measurements of host tree stem growth, canopy turnover and stand structure in a severely infected temperate eucalypt woodland to monitor how mistletoe infection alters aboveground biomass distribution and to assess ecosystem recovery from severe mistletoe infection during and after a three-year drought. We show that severe mistletoe infection reduces live standing biomass and canopy volume, with mistletoe leaves contributing up to 43% to total stand litter fall. We further identified that a mistletoe:host leaf area ratio above 60% significantly reduced basal area growth, which provides a threshold for productivity losses due to mistletoe infection in eucalypts. Yet, concurrent increases in basal area and the thickening of canopy volume indicate that host trees recover rapidly after the three-year drought combined with record summer heat nearly extinguished the mistletoe population. How common, or how widespread such dynamic changes in mistletoe population dynamics are within Australian or global ecosystems remains subject to further exploration.

Ficus L., commonly known as Fig, is a member of the family Moraceae (mulberry family) comprises 37 genera and approximately 1,100 species distributed in diverse ecosystems, especially in tropical and temperate regions of the world. The Ficus genus stands out as a keystone resource provider in many tropical forests, which is probably because of continuous non-seasonal fruiting in many species. It is one of the largest genera in the angiosperms about 750 species. The present study was carried out in the Forest Research Institute (FRI) campus, Dehradun (Uttarakhand), India. The phytodiversity of Ficus L. and their socio-economic values worked out during the investigation, religious-spiritual attachment, food of wild animals, ethnomedicinal and timber significance. There were 16 species of Ficus L. recorded from New Forest, FRI, Dehradun based on the morphological observations of taxonomically significant characteristics. The species found in FRI New Forest Dehradun were, Ficus benjamina, F. religiosa, F. racemosa, F. rumphii, F. retusa, F. krishnae, F. elastica, F. virens, F. semicordata, F. auriculata, F. hispida, F. pumila, F. palmata, F. drupacea, F. benghalensis, F. pomifera. Out of the notified 16 species of Ficus, 11 species were trees, 3 shrubs and 2 climbers in nature. The maximum leaf size (30×27cm2) was reported in F. auriculata, followed by F. semicordata (28×10cm2), F. benghalensis (25×11cm2). However, minimum leaf size was noticed in F. benjamina (4×2cm2) and F. retusa (4×3cm2). Among, 15 species, axillary fig (fruit) arrangement was observed, while one species (F. racemosa) has stem position of fruits. The current finding is itself a pioneer study to present a glimpse of such immense species diversity of single genera from sub-valley areas and will be a milestone for future studies in conservation and management of these wild varieties.

Laternula elliptica is a key bivalve species and widely distributed around the Antarctic continent. This bivalve has been the study subject in several studies centered on ecological, physiological, biochemical, and behavioral patterns. However, little is known about the chemistry and the biomechanical properties of the shells of this mollusk. Here, we present the first report of the intra-population variability in the organic composition and mechanical properties of L. elliptica shells. Further, we analyze different morphological traits and their association with the metabolism of a population of L. elliptica from King George Island, Western Antarctic Peninsula. The summer metabolic rates and the hepatosomatic index values indicate good health conditions of this clam’s population. Shell periostracum chemistry is quite similar to bivalves from temperate regions, but the relative amount of protein increased ca. five-fold in shells of L. elliptica. The microhardness is approximately 32% lower than in bivalves from temperate regions. Our characterization of the L. elliptica shells suggests that periostracum chemistry could be specially fitted to avoid shell carbon exposure to dissolution (e.g., in corrosive acidified seawater). In contrast, the reduction in shell hardness may result from prioritizing behavioral (burial) and shell repairing strategies to confront biological (predators) and physical disturbances (e.g., ice scouring). Similar studies in other Antarctic mollusks will help understand the role of shell structure and function in confronting projected climate changes in the Antarctic ocean.

Nelsonia is an extant genus of North American woodrats, in which most of the biological information remains unknown. Only N. neotomodon and N. goldmani are recognized inhabiting in similar temperate environments. Recently, a biogeographic hypothesis for the genus pointed out that Nelsonia after diverging from Repomys or Protorepomys in the Californian-Rocky Mountains in USA, the Mexican highlands in Mexico played a significant role in how the two species of Nelsonia became established in two different mountain ranges: N. neotomodon in the Sierra Madre Occidental and N. goldmani in the Transmexican Volcanic Belt. However, no other evidence exists about the biogeographic history of both species that improve the explanation about how past climate events affected their distribution, as well as whether the current environmental space occupied by both species are similar such as previous studies have argued. Therefore, this study aimed to characterize the environmental niche of both species, to test environmental differences, overlap, equivalence, and niche similarity, and lastly, to build their current niche model and paleodistribution for three past scenarios: Pliocene, Last Interglacial, and Last Glacial Maximum. The results revealed significant differences in niche centroid, low niche overlap, and no niche equivalence or similarity, suggesting niche divergence. The current niche suitability showed that the two species have small and restricted potential habitats highlighting the need to reevaluate the current international conservation category of N. neotomodon. The paleodistribution suggested that both species of Nelsonia have contractions and expansions of niche suitability in the past.

Summary Fungi are known to exert a significant influence over soil organic matter (SOM) turnover, however understanding of the effects of fungal community structure on SOM dynamics and its consequences for ecosystem fertility is fragmentary.Here we studied soil fungal guilds and SOM decomposition processes along a fertility gradient in a temperate mountain beech forest. High-throughput sequencing was used to investigate fungal communities. Carbon and nitrogen stocks, enzymatic activity and microbial respiration were measured.While ectomycorrhizal fungal abundance was not related to fertility, saprotrophic ascomycetes showed higher relative abundances under more fertile conditions. The activity of oxidising enzymes and respiration rates in mineral soil were related positively to fertility and saprotrophic fungi. In addition, organic layer carbon and nitrogen stocks were lower on the more fertile plots, although tree biomass and litter input were higher. Together, the results indicated a faster SOM turnover at the fertile end of the gradient.We suggest that there is a positive feedback mechanism between SOM turnover and fertility that is mediated by soil fungi to a significant extent. By underlining the importance of fungi for soil fertility and plant growth, these findings furthermore emphasise the dependency of carbon cycling on fungal communities below ground.

Litter decomposition is an ecosystem process that allows energy and nutrients transfer from dead plant matter into detrital food webs. Several studies revealed that leaf litter decomposition rates differ across biomes, but the reasons for these differences are not yet clear. Here, we test the role of several leaf litter physical and chemical characteristics as predictors of decomposition rates and whether life forms (evergreen vs. deciduous) differ in decomposition rates. Leaves from dominant riparian trees were collected in four ecoregions (temperate deciduous forest, subtropical seasonal semideciduous forest, tropical Cerrado and subtropical dense ombrophylous forest) and their physical and chemical characteristics were measured. We then determined leaf litter decomposition, colonization by aquatic hyphomycetes and macroinvertebrates in a same stream (i.e., under the same environmental conditions), and consumption rates by shredders under laboratory conditions. Deciduous and evergreen tree species did not differ in the measured litter characteristics, but deciduous leaves decompose faster than evergreens. Leaf litter from tree species from the four ecoregions differed in their physical and chemical characteristics. Litter from temperate deciduous species decomposed faster than litter from the other three ecoregions, generally supported higher aquatic hyphomycete species richness and sporulation rates and higher consumption rates by shredders. There were significant negative correlations between litter decomposition and associated biotic variables and litter initial lignin concentration and lignin:N ratio. We conclude that lignin concentration and lignin:N ratio are important predictors of litter decomposition, although other unmeasured parameters such as micronutrients may also play important roles in this key ecosystem process.

Many species are responding to global warming by shifting their distributions upslope to higher elevations, but the observed rates of shifts vary considerably among studies. Here we test the hypothesis that this variation is in part explained by latitude, with tropical species being generally more responsive to warming temperatures than are temperate species. We find support for this hypothesis in each of two independent empirical datasets—shifts in species’ elevational ranges, and changes in composition of forest inventory tree plots. Tropical species are tracking rising temperatures 2.1–2.4 times (range shift dataset) and 10 times (tree plot dataset) better than their temperate counterparts. Models predict that for a 100 m upslope shift in temperature isotherm, species at the equator have shifted their elevational ranges 93–96 m upslope, while species at 45° latitude have shifted only 37–42 m upslope. For tree plots, models predict that a 1°C increase in temperature leads to an increase in community temperature index (CTI), a metric of the average temperature optima of tree species within a plot, of 0.56 °C at the equator but no change in CTI at 45° latitude (–0.033). This latitudinal gradient in temperature tracking suggests that tropical montane biotas may be on an “escalator to extinction” as global temperatures continue to rise.

Stomatal and mesophyll conductance were the dominant limitations to photosynthesis in response to heat stress during severe drought in both a temperate and a tropical tree species. Drought and heat stress cause a significant reduction in forest primary production. The current study aims to determine the major limitations to photosynthesis in a temperate and tropical tree species experiencing a combination of drought and heat stress; an increasingly common situation in the face of climate change. Two tree species, one temperate (Fraxinus chinensis) and the other tropical (Radermachera sinica) were subjected in growth chambers to a 2-day heat stress of 40 °C during ca. 2-week period of drought, followed by re-watering. The limitations by three factors that affect photosynthesis (stomatal and mesophyll conductance, and biochemical processes) were partitioned based on measurements of gas exchange, net assimilation rate—intercellular CO2 concentration (Anet—Ci) curves and chlorophyll fluorescence. Under the drought-only condition, photosynthesis was primarily limited by stomatal conductance in both species. Unexpectedly, heat stress did not further reduce photosynthesis during drought in either tree species. In both species, carbon assimilation during drought and added heat stress was primarily limited by stomatal and mesophyll conductance. Drought decreased mesophyll conductance in both species but the effects were more pronounced in the tropical tree species, R. sinica. Biochemical limitation remained low throughout the stress period. These results suggest the importance of balancing water conservation and transpirational cooling in the diffusive pathway in response to, not only drought, but also the combination of water and heat stress in forest trees.

Context Mangroves and intertidal habitats have been identified as particularly challenging environments for bait application within both tropical and temperate environments, because bait applied to areas that are tidally inundated could degrade rapidly or become inaccessible to rats. Aims To determine rat density, ranging behaviour and probability of detection using different monitoring devices; additionally, to determine the availability (persistence, durability and uptake) of rodenticide baits within tidally inundated mangrove habitats. Methods The population biology of black rats (Rattus rattus) was studied in two contrasting mangrove habitats on Europa Island, and spatially explicit mark–recapture studies were performed to estimate densities and activity of rats. A series of bait availability trials was conducted to determine the durability of rodenticide baits on the ground and uptake in the canopy (‘bait bolas’). Key results Black rats were found to be abundant in mangrove, and despite daily tidal inundation, still maintained ranging behaviour consistent with rats in adjacent terrestrial habitats. Larger rodenticide bait blocks remained within tidally inundated habitat throughout tidal cycles and were available and remained palatable to rats for at least three consecutive nights, although strong bait competition occurred with crabs. Bait bolas were available in mangrove canopy exclusively to rats and consumption commenced on the first night. Conclusions The results provide evidence that mangrove habitats are an important habitat for rats, but the biology of rats in these habitats does not meaningfully differ from adjacent terrestrial habitats. With the use of larger rodenticide blocks, tidal inundation does not affect bait availability, but crabs remain a major competitor for these baits. Alternatively, the present study revealed that bait bolas limit bait access to rats alone. Development as an aerial eradication technology should be also recommended. Implications These results provide a proof of concept that eradication of rats from tidally inundated habitats such as mangrove should be possible with only small modifications to current best practice.

Scavenging is an important function within ecosystems where scavengers remove organic matter, reduce disease, stabilize food webs, and generally make ecosystems more resilient to environmental changes. Global change (i.e., changing climate and increasing human impact) is currently influencing scavenger communities. Thus, understanding what promotes species richness in scavenger communities can help prioritize management actions. Using a long-term dataset from camera traps deployed with animal carcasses as bait along a 1881 km latitudinal gradient in the Appalachian Mountains of eastern USA, we investigated the relative impact of climate and humans on the species richness and diversity of vertebrate scavengers. Our most supported models for both mammalian and avian scavengers included climatic, but not human, variables. The richness of mammalian and avian scavengers detected was highest during relatively warm (5-10°C) and dry (100-150 mm precipitation) winters, when food was likely limited and both reliance on and detection of carrion was high. The diversity of mammalian and avian scavengers detected was highest under drier conditions. We then used these results to project the future species richness of scavengers that would be detected within our sampling area and under the climate scenario of 2070 (emissions level RCP8.5). Our predictions suggest up to 80% and 67% reductions, respectively, in the richness of avian and mammalian scavengers that would be detected at baited sites. Climate-induced shifts in behavior (i.e., reduction in scavenging, even if present) at this scale could have cascading implications for ecosystem function, resilience, and human health. Further, our study highlights the importance of conducting studies of scavenger community dynamics within ecosystems across wide spatial gradients within temperate environments. More broadly, these findings build upon our understanding of the impacts of climate-induced adjustments in behavior that can likely have negative impacts on systems at a large scale.

Understanding the mechanisms of biological invasion is fundamental for biodiversity conservation in the Anthropocene. This study focused on a large-scale colonization pattern of exotic seed plants, which include 1094 species characterized by different geographical origins, into the insular flora of Japan. We investigated a nation-wide pattern of species richness and phylogenetic structure (clustering/over-dispersion) of exotic and its recipient native species (4664 species). We tested the invasion hypotheses associated with environmental filtering, biological resistance of recipient assemblages, human disturbance and biogeographical origins of exotics. The exotics originated from the same (Palearctic and Indo-Malay) and adjacent (Nearctic and Oceanic) biogeographical regions were widely distributed across the country under temperate climate condition, whereas tropical exotic plants from remote regions (Afrotropic, Australasian, and Neotropical) colonized mainly the south-western parts of Japan. Exotic species richness and phylogenetic structure, especially those from the same/adjacent regions, were well explained by climatic, edaphic, and topographic factors, supporting the environmental filtering hypothesis. For all the biogeographical origins, exotic richness was positively associated with native richness, opposing the biological resistance hypothesis. Human disturbance was positively associated with exotic richness, while its relationships with the exotics’ phylogenetic structure varied according to their biogeographical origins. These findings indicate that site’s invasibility was determined by the combination of exotic’s biogeographical origins and abiotic/biotic conditions of its recipient native flora. Our results suggest that global warming may accelerate the northward expansion of tropical exotic plants while future land-use changes can promote biological invasion regardless of exotics’ origins.

Endodormancy and the related chilling requirement synchronize the seasonal development of trees from the boreal and temperate regions under the climatic conditions prevailing at their native growing sites. The phenomenon of endodormancy has been known at the whole-plant level for 100 years, and in the last couple of decades, insights into the physiological and molecular basis of endodormancy and its release have also been obtained. Intriguingly, recent studies have shown experimentally that subtropical trees also show endodormancy and a chilling requirement. Motivated by the climatic differences between the subtropical and more northern zones, here we address the similarities and differences in endodormancy between trees growing in the subtropical zone and those growing in more northern zones.

Breeding in perennial fruit crops is time consuming process with relatively low success rate as compared with annual crops. Apple fruit coloration is painstaking as noticeable marker of maturity (early to late) and outer quality during the fruit breeding. The occurrence of spontaneous bud mutations in plants has often led to their subsequent development as commercial cultivars. Keeping in view, present investigation was undertaken to identify bud sports in apple (Malus domestica Borkh.) in H.P. of India. In this study, based upon pre-selection criteria such as time of colour development and time of fruit maturation were implemented, one bud sport ‘Kalpa 1’ was identified as distinctive late in fruit skin development as compared to fully red coloured fruits on its mother tree of cv. Starking Delicious in H.P. India with red streaked fruits over yellow ground colour on the bud sports did not mature even at harvesting, respectively. Apart from the distinguishing character for which the bud sports were identified, they also differed in fruit shape and size, fruit firmness, fruit maturity, TSS, acidity and starch iodine test strain area. The identified bud sport has unique character of late maturity indices in H.P. This unique variety can be grown in other temperate regions of India with the same soil and climatic condition.

The utility of elevational gradients as tools to test either ecological hypotheses and delineate elevation‐associated environmental factors that explain the species diversity patterns is critical for moss species conservation. We examined the elevational patterns of species richness and evaluated the effects of spatial and environmental factors on moss species predicted a priori by alternative hypotheses, including mid‐domain effect (MDE), habitat complexity, energy, and environment proposed to explain the variation of diversity. Last, we assessed the contribution of elevation toward explaining the heterogeneity among sampling sites. We observed the hump‐shaped distribution pattern of species richness along elevational gradient. The MDE and the habitat complexity hypothesis were supported with MDE being the primary driver for richness patterns, whereas little support was found for the energy and the environmental factors., We observed the hump‐shaped distribution pattern of species richness along elevational gradient. The mid‐domain effect (MDE) and the habitat complexity hypothesis were supported with MDE being the primary driver for richness patterns, whereas little support was found for the energy and the environment. Moss species richness pattern in the mountain is driven by ecological and evolutionary effects, whereas evolutionary factors predominately shape the large heterogeneity through dispersal, extinction, and speciation processes.

Terrestrial ecosystems are experiencing increasing frequency and intensity of droughts as a result of climate change. Despite a wealth of previous studies investigating soil responses to drought, the importance of historical land use in mediating drought effects remains poorly understood. To identify interactions between drought and historical land use, we sampled soils from two adjacent forested watersheds at the USFS Coweeta Hydrologic Laboratory: a ‘reference’ forest that has remained undisturbed for approximately a century and a ‘disturbed’ forest with a history of conversion to pasture followed by abandonment to forest succession. We incubated intact soil cores in the laboratory under one of two moisture treatments: a constant moisture control and a drought-rewet treatment, which involved a six-week drought followed by rewetting and six additional weeks at constant moisture. We measured respiration and characterized soil C and N pools and microbial communities multiple times throughout the experiment. Soils exposed to drought-rewetting had higher cumulative respiration than control soils, which was driven by particularly strong respiration responses of disturbed soils. In addition, drought-rewetting reduced microbial biomass and increased total extractable N and NH4+, with greater responses in reference watershed soils. Microbial communities also exhibited responses, with increased biomass C:N, increased fungal:bacterial ratios, and decreased nitrifier abundance in response to drought-rewetting. Overall, our results show that drought responses of forests will vary among land use histories and among soil parameters, which should be considered when seeking to predict biogeochemical responses of temperate ecosystems to climate stressors such as intensifying droughts.

During soil drought (i.e., limited soil water availability to plants), woody species may adjust the structure of their vessel network to improve their resistance against future soil drought stress. Impacts of soil drought on intervessel lateral contact remain poorly understood despite of its significance to xylem transport efficiency and safety. Here, we analysed drought-induced modifications in xylem structures of temperate angiosperm trees with a focus on intervessel lateral contact. Anatomical analyses were performed both in stems of seedlings cultivated under different substrate water availability and annual rings of mature individuals developed during years of low and high soil drought intensities. In response to limited water availability, a decrease in vessel diameter (up to -20%) and simultaneous increase in vessel density (up to +60%) were observed both in seedlings and mature trees. Conversely, there were only small and inconsistent drought-induced changes in intervessel contact frequency and intervessel contact fraction (typically up to ±15%) observed across species, indicating that intervessel lateral contact is a conservative trait. The small adjustments in intervessel lateral contacts were primarily driven by changes in the contact frequencies between neighbouring vessels (i.e., vessel grouping) rather than by changes in proportions of shared cell walls. Our results demonstrate that angiosperm tree species, despite remarkable adjustments in vessel dimensions and densities upon soil drought, exhibit surprisingly invariant intervessel lateral contact architecture. This article is protected by copyright. All rights reserved.

The growing interest in commercial cultivation of bamboos (Poaceae subfamily Bambusoideae) has led to the introduction of new alien species into South Africa. The rate at which bamboos are being planted in South Africa is a cause for concern because of the impacts of bamboo invasions in other parts of the world. To understand the risks associated with new introductions and new plantings, we assess the outcomes of past introductions of bamboos into South Africa. To this end we: (1) produce an inventory of alien bamboo taxa; (2) assess the distribution of bamboos; (3) determine the rate of spread of bamboo at a site with a high density of naturalised stands; and (4) evaluate the current regulatory status of alien bamboos in South Africa. We used a combination of expert opinion, literature, historical records of populations, and public participation to produce a species list and locate populations of alien bamboos. We also attempted to confirm species identities using DNA barcoding. We found that 28 currently-accepted species of bamboo have been recorded in South Africa. However, we have little confidence in this estimate, as 20 of the species could not be confirmed or identified as present in the country. Bamboos are an inherently challenging group to identify using vegetative material, and DNA barcoding was inconclusive. The distribution of bamboos across the country varied with the type or lineage (e.g. herbaceous, tropical or temperate) and the source of information (e.g. herbarium records, in-field observation or public contribution). Although alien bamboos are naturalised at several sites, we found no large invasive stands nor evidence of widespread negative environmental impacts. Nonetheless, we recommend caution regarding future introductions of bamboos for commercial cultivation, as the nature of the plantings will likely differ from the historical situation in both the location, configuration, and the scale of cultivation, and as new species are likely to be introduced. We propose several changes to the current listing of bamboo taxa in national legislation pertaining to alien and invasive species.

Eisenia arborea Areschoug is a temperate kelp first described from California, and commonly reported as far south as Mexico. Floristic surveys in cold-temperate waters of the Northeast Pacific, however, have revealed its presence on the Canadian archipelago of Haida Gwaii (at latitude 53.3799°N), last reported from the area in 2000 by Sloan and Bartier. Here, we present COI-5P data for E. arborea and confirm its presence at two sites on the west coast of Haida Gwaii in the years 2015 and 2018. These collections update a recently published list of genetically confirmed kelp species from Haida Gwaii. Our surveys suggest that northern populations of E. arborea are likely scattered throughout the western portions of the archipelago. The Haida Gwaii populations reported here represent potential monitoring sites for ecological and evolutionary investigations of E. arborea.