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Cliffs are marginal and poorly studied habitats that are home to a high proportion of endemic or threatened species. Here, we reviewed the survival patterns and population dynamics of plants growing on vertical cliffs and compared them to other plants with similar life forms that grow on the ground. To this end, we have compiled studies of cliff and ground-level plants from two main sources: MONITO and COMPADRE. The resulting dataset after applying some filters included a total of 243 populations of 134 plant species monitored for several years in the northern hemisphere. We tested whether survival rates of seedlings and older stages, population growth rates, and their temporal variability showed similar patterns between cliff and ground plants, and the relationship between those demographic parameters. Cliff plants showed higher survival rates for both seedlings and older life stages, as well as lower distance to population equilibrium and more stable population trends over time, compared to plants growing in the ground. Population equilibrium and temporal stability was highly correlated with the survival of post-seedling stages in both groups. These results suggest that cliff plants may be better adapted to withstand climatic variability than the more common ground-level plants occurring in less stressful environments. [ABSTRACT FROM AUTHOR]

Cliffs are marginal and poorly studied habitats that are home to a high proportion of endemic or threatened species. Here, we reviewed the survival patterns and population dynamics of plants growing on vertical cliffs and compared them to other plants with similar life forms that grow on the ground. To this end, we have compiled studies of cliff and ground-level plants from two main sources: MONITO and COMPADRE. The resulting dataset after applying some filters included a total of 243 populations of 134 plant species monitored for several years in the northern hemisphere. We tested whether survival rates of seedlings and older stages, population growth rates, and their temporal variability showed similar patterns between cliff and ground plants, and the relationship between those demographic parameters. Cliff plants showed higher survival rates for both seedlings and older life stages, as well as lower distance to population equilibrium and more stable population trends over time, compared to plants growing in the ground. Population equilibrium and temporal stability was highly correlated with the survival of post-seedling stages in both groups. These results suggest that cliff plants may be better adapted to withstand climatic variability than the more common ground-level plants occurring in less stressful environments.

This research is motivated by the lack of use of interesting learning media for students. Teachers still do not use interactive learning media, only using textbooks containing the material. This research aims to develop Microsite learning media in the science and sciences subject for material on Harmony in Ecosystems for class V elementary school. This type of research and development uses Research and Development (RnD) research with the ADDIE (Analyze, Design, Development, Implementation and Evaluation) development model. The five stages of analysis will be carried out through analysis of material, language and media which will be validated by the Principal of SD N Tegaldowo, namely Mrs. Riri. Practicality is carried out by distributing questionnaires to teachers and students to see the responses given, while for effectiveness it is carried out by distributing questions to students. to test their learning abilities with microsite learning media. The results of developing this microsite learning media were declared Very Valid. Based on the results obtained from validator media with an average of 83%, it is in the Very Valid category with practicality results with an average of 87% being considered Very Practical and for effectiveness with an average of 87% and recommended as Very Effective. Thus, it can be concluded that the Microsite learning media that has been created and developed is very valid, practical and effective for use by teachers during learning activities. [ABSTRACT FROM AUTHOR]

Aerial seeding with drones has great potential in forest restoration but faces enormous challenges to be efficient and scalable. Current protocols use blanket seeding throughout the area to be restored, meaning a high demand for seed since many seeds arrive in sites unsuitable for establishment. High precision seeding directed to safe microsites at submeter scale could reduce seed use per hectare, reducing economic and ecological costs, while increasing establishment success. Here, we propose an alternative, precision approach to make drone seeding more successful and efficient. This requires (1) submeter‐scale selection of target microsites for seeding founded in ecological knowledge; (2) high‐resolution remote sensing imagery to train artificial intelligence (AI) systems in target microsite recognition; and (3) process automation by transferring target microsite coordinates from the AI system to the drone. This will reduce seed inputs per unit area, seedling establishment failure risks, and drone operation costs. [ABSTRACT FROM AUTHOR]

Penelitian ini bertujuan untuk mengembangkan media pembelajaran berbasis microsite untuk materi Pancasila pada siswa kelas V Sekolah Dasar. Metode penelitian yang digunakan adalah model pengembangan Richey dan Klein yang meliputi tiga tahap: desain, produksi, dan evaluasi. Analisis kebutuhan fungsional dan non-fungsional dilakukan untuk menentukan elemen-elemen penting dalam pembuatan microsite. Validasi oleh ahli materi dan media menunjukkan bahwa microsite ini sangat valid dengan nilai persentase masing-masing di atas 90%. Penggunaan microsite dalam pembelajaran memberikan beberapa keunggulan seperti kemudahan akses, fleksibilitas, dan kemampuan untuk menyajikan media lain yang mendukung proses belajar. Uji coba pada 20 siswa menunjukkan peningkatan hasil belajar yang signifikan, terlihat dari perbandingan skor pretest dan posttest. Hasil penelitian ini mengindikasikan bahwa penggunaan microsite dapat meningkatkan pemahaman siswa terhadap materi Pancasila, memotivasi mereka untuk belajar, dan menyediakan pengalaman belajar yang lebih terstruktur dan menarik. Oleh karena itu, penerapan teknologi dalam pendidikan, khususnya melalui media microsite, merupakan langkah penting untuk memajukan sistem pembelajaran yang adaptif dan inovatif.

A novel multistatic integrated sensing and communication (ISAC) system based on macro–micro cooperation for the sixth-generation (6G) mobile network is proposed. Instead of using macrosites at both the transmitter and receiver sides, microsites are considered as receivers in cooperative sensing. This system is important since microsites can be deployed more flexibly to reduce their distances to the sensing objects, providing better coverage for sensing service. In this work, we first analyze the deployment problem of microsites, which can be deployed along the radius and azimuth angle to cover macrosite cells. The coverage area of each microsite is derived in terms of its position in the cell. Then, we describe an efficient estimating approach for obtaining the position and velocity of sensing objects in the macrosite cell. By choosing multiple microsites around the targeted sensing area, joint data processing with an efficient optimization method is also provided. Simulation results show that the multistatic ISAC system employing macro–micro cooperation can improve the position and velocity estimation accuracy of objects compared to systems employing macrosite cooperation alone, demonstrating the effectiveness and potential for implementing the proposed system in the 6G mobile network. [ABSTRACT FROM AUTHOR]

Road construction generates environmental impacts on ecosystems, fragmenting and transforming habitats. They affect the assemblage of species in degraded areas, contributing to the introduction and increase of invasive exotic plant species. The introduction of invasive species changes the abundance and composition of native species, which represents a threat to global biodiversity. Our objective was to analyze the standing vegetation assemblage and seed bank and to identify invasive species in roadsides embankment of Nothofagus antarctica shrublands in northwest Patagonia. The composition, richness, diversity, and abundance of exotic and native species and functional groups of the standing vegetation and in the seed bank were analyzed on road slopes and reference areas. The road slopes presented different floristic composition, with lower total vegetation cover and seed density, lower richness and cover of native species, and lower seed density of exotic species than the reference areas. The similarity between standing vegetation and seed bank was high for exotic species. The vegetation on the slopes of the road was dominated by annual/biannual and perennial herbs and exotic invasive species and by native perennial herbs and grasses and shrubs; no shrub seeds were found there. The presence of exotic species on road slopes may respond to the conditions of the microsites and the traits of the species that colonize them, such as their ability to form seed banks, their high seed production, or their life form and life cycle. This work showed that in the shrublands of northwestern Patagonia, roadsides and nearby areas present potentially invasive exotic species, highlighting the importance of early identification for their control. [ABSTRACT FROM AUTHOR]

Background: Due to the effects of climate change and overgrazing in recent decades, alternative stable states in the alpine Kobresia meadow degradation process have coexisted in the same geographical and climatic environment, with variations occurring among microsites. Methods: We used a space‐for‐time substitution approach to explore the synergies of microsite variation according to its numerical characteristics and the proportion of each stable state at various stages of succession in alpine Kobresia meadows on the Qinghai–Tibetan Plateau. Results: (1) The highest average aboveground biomass in summer was 196.2 ± 20.3 g m−2, with significantly higher levels of biomass in ≤3.65 sheep unit ha−1 than in other levels of grazing intensity, while the parameters showed no significant differences among grazing intensity levels in >3.65 sheep unit ha−1. (2) The importance of plant functional groups, aboveground biomass, and niche breadth of Poaceae and Cyperaceae significantly decreased as the grazing intensity increased. (3) The effects of ≥0°C accumulated temperature, total precipitation, altitude, longitude, and latitude cumulatively contributed less than 20% of the variation in the distribution of functional group characteristics across microsites. Conclusions: (1) Overgrazing decreases primary production in alpine Kobresia meadows, but ecosystem responses regulate plant community structure and botanical components so as to partially counteract grazing disturbance. (2) Overgrazing changed the proportion of microsites, which in turn led to regime shift in the plant community and subsequent synergies between the microsites of plant communities and their stable states. [ABSTRACT FROM AUTHOR]

Many plant species exhibit strong seed dormancy. This attribute benefits the species' long-term survival but can impede restoration when rapid establishment is required. Soaking seeds in gibberellic acid (GA3) can overcome dormancy and increase germination but this treatment may not be effective outside the laboratory. An easier and potentially more effective method to apply this hormone is to coat seeds with a GA3-impregnated polymer. Seed dormancy can also be mitigated by creating a favorable microsite with increased soil moisture. We compared the emergence and establishment of penstemon seeds coated with GA3 to those of uncoated seeds planted in shallow drill rows versus deep, U-shaped furrows. Overall, 6 times more Palmer's penstemon (Penstemon palmeri; p < 0.01) and 21 times more thickleaf penstemon (P. pachyphyllus; p < 0.001) established when coated with GA3, but GA3 coating did not affect the establishment of firecracker penstemon (P. eatonii; p = 1). Establishment was higher from deep furrows than shallow rows (p < 0.001). These results indicate that GA3 seed coating and deep, U-shaped furrows may improve the restoration success of some native forbs by breaking dormancy and providing a favorable microsite. Land managers could use these techniques to restore native forbs in dry, disturbed areas. [ABSTRACT FROM AUTHOR]

Masalah dalam penelitian ini adalah siswa kesulitan dalam memahami materi klasifikasi makhluk hidup dan kesulitan menghafal nama-nama ilmiah. Peneliti berusaha merancang suatu media yang cocok untuk mengatasi permasalahan tersebut. Penelitian ini bertujuan untuk mengembangkan media pembelajaran yang tepat sesuai dengan permasalahan dalam pembelajaran Biologi dan mengembangkan media pembelajaran berupa flashcard materi klasifikasi makhluk hidup yang panduan penggunaan, materi, serta kuisnya dapat diakses melalui microsite. Penelitian ini dilakukan di SMA Negeri 2 Gorontalo. Metode penelitian yang digunakan adalah metode kualitatif yang memberikan penjelasan lebih analisis dan bersifat subjektif. Desain yang digunakan yaitu R&D model Borg and Gall yang telah dimodifikasi oleh Sugiyono, dengan melaksanakan 6 tahap dari 10 tahapan yaitu analisis potensi dan masalah, mengumpulkan informasi, desain produk, validasi oleh ahli, revisi desain, dan revisi produk. Teknik pengumpulan data dengan melakukan wawancara. Penentuan kelayakan dilakukan dengan melakukan validasi pada ahli bahasa, ahli materi, dan ahli media. Penelitian dan pengembangan menghasilkan media flashcard yang berbentuk kartu bolak-balik yang layak digunakan berdasarkan penilaian dari (1) validator ahli bahasa memperoleh penilaian 90% (2) validator ahli materi memperoleh penilaian 100%, (3) validator ahli media memperoleh penilaian 95%. Dengan demikian, dapat disimpulkan bahwa produk flashcard pada materi klasifikasi makhluk hidup (hewan dan tumbuhan) secara keseluruhan kualitasnya sangat baik dan layak digunakan sebagai media pembelajaran untuk siswa kelas X.

A novel multistatic integrated sensing and communication (ISAC) system based on macro–micro cooperation for the sixth-generation (6G) mobile network is proposed. Instead of using macrosites at both the transmitter and receiver sides, microsites are considered as receivers in cooperative sensing. This system is important since microsites can be deployed more flexibly to reduce their distances to the sensing objects, providing better coverage for sensing service. In this work, we first analyze the deployment problem of microsites, which can be deployed along the radius and azimuth angle to cover macrosite cells. The coverage area of each microsite is derived in terms of its position in the cell. Then, we describe an efficient estimating approach for obtaining the position and velocity of sensing objects in the macrosite cell. By choosing multiple microsites around the targeted sensing area, joint data processing with an efficient optimization method is also provided. Simulation results show that the multistatic ISAC system employing macro–micro cooperation can improve the position and velocity estimation accuracy of objects compared to systems employing macrosite cooperation alone, demonstrating the effectiveness and potential for implementing the proposed system in the 6G mobile network.

IntroductionIncreasing temperatures associated with climate change can lead to more challenging conditions for tree seedlings, including greater soil surface temperatures and reduced growing season soil moisture. Downed woody debris (DWD) may provide microsite effects, such as shade, that moderate these conditions for seedlings. However, few studies have conducted fine-scale assessments of the strength of the microsite as a function of distance from DWD or how the microsite effect differs between species or across topographic gradients.MethodsIn this study, conducted in the Palouse region of eastern Washington State, we placed three large pieces of DWD (5 m length × 40–50 cm small-end diameter, oriented east–west) on each of three topographic facets (north-facing, flat ridge-top, and south-facing), and planted transects of seedlings of a xerophytic conifer (ponderosa pine, Pinus ponderosa) and a mesophytic conifer (Douglas-fir, Pseudotsuga menziesii) on both sides of the DWD at fixed distances (0, 0.25, 0.5, and 1.5 m). The 1.5 m distance was assumed to serve as a control, with no measurable influence from DWD. Seedling responses (stress rating, survival, basal diameter and height growth, and dark-adapted chlorophyll fluorescence) over two growing seasons were used to interpret the influence of DWD on seedling health and survival, especially during stressful episodes of extreme heat, such as occurred during July 2021, the first growing season of the experiment. Soil surface temperature and soil volumetric water content (10 cm depth) were measured at all seedling locations to understand biophysical contributors to seedling response.ResultsWe found that seedlings of both conifers displayed lower stress ratings, higher survival, and greater height growth close to the north side of DWD, with this effect especially pronounced on the flat ridge-top and the south-facing slope. Soil surface temperature decreased greatly in the “shade zone” at 0.0 m and 0.25 m distances on the north side of DWD, and soil volumetric water content declined more quickly outside of the shaded microsite.DiscussionThese findings suggest that creating or retaining DWD on stressful sites may prove an important climate adaptive management strategy in ecosystem restoration or forest management, especially if extreme heat events continue to increase in frequency.

Adapting to site conditions is a central part of forest regeneration and can be done through selection of different planting positions. Requirements are tree species specific, and the use of soil moisture maps could be a way to support decision making in forest regeneration planning. At two experimental sites with varying soil moisture conditions in southern Sweden Norway spruce (Picea abies (L.) Karst.), Scots pine (Pinus sylvestris L.), and silver birch (Betula pendula Roth) seedlings were planted in four different planting positions following mounding site preparation; Depression, Hinge, Mound and Unscarified. Soil moisture estimates were obtained from a high-resolution depth-to-water raster for each planting spot. The effect of soil moisture, planting position and their interactions on mortality, height and diameter was evaluated for each tree species. In wet conditions mounds proved to be the best option to minimize seedling mortality for conifers, but with decreasing soil moisture, differences between the planting positions decreased. Birch on the other hand had the greatest survival in the hinge. The coniferous species displayed increased height and diameter when planted in mounds independent of the soil moisture conditions, whereas silver birch was less dependent on a specific planting position. Results from this study shows that a soil moisture map can explain mortality, height and diameter and thus can be a useful tool when choosing planting position in different soil moisture conditions.

Aim of study: Detecting possible small-scale soil effects on height growth of single trees in monospecific stands of three important tree species (Abies alba, Fagus sylvatica, and Picea abies). Area of study: 37 mature stands along an ecological gradient in Southern Germany from the cold and wet “optimal niche zone” to warmer and drier niche zones, including gravelly soils with poor water supply. Material and methods: Measurement of achieved height and age of 15 to 20 sample trees per stand. Estimation of the available water capacity of the soil (AWC) in close proximity to sample trees based on soil texture following the German soil survey guidelines. Examining height growth depending on niche zone and AWC. Main results: On sites (stand level) with the lowest water regime, height growth increased significantly with AWC of microsites. The estimated effect on height growth over the whole range of AWC values was almost 8 m at those sites. In contrast, the effect was negative on optimal sites. For intermediate and marginal sites, the effect was positive, albeit not significant for marginal sites. Research highlights: To our knowledge this is the first study about small-scale effects of AWC on height growth of single trees in temperate European forests. Small-scale soil variability should be considered in future scientific studies and practical evaluation, involving single tree performance at stands with low water regime. This seems particularly important in genetic environmental associations studies and in the process of selecting trees for breeding purposes in such stands.

It is well documented that the recovery of dryland plant communities following wildfire can be variable, and that legacies of fire can have long‐lasting effects on aboveground plant communities. However, our understanding of the degree to which dryland soil seed banks, or the viable seeds in situ, are impacted by fire and their subsequent postfire succession remains extremely poor. To address this important knowledge gap, we used a time‐since‐fire approach to investigate soil seed bank community changes approximately 15 and 30 years after wildfire and to determine the influence of microsites (e.g., shrub vs. interspace) on seed bank composition. We assessed soil seed bank metrics across four North American deserts, including two cold desert sites (Colorado Plateau and Great Basin) and two warm desert sites (Chihuahuan and Sonoran). In greenhouse emergence trials, we found that seed bank characteristics diverged between warm and cold desert sites, such that warm desert sites had seed banks dominated by annual plants while our cold desert sites had seed banks with greater proportions of perennial species, regardless of fire history. In cold desert sites, fire significantly altered seed bank species composition even 30 years after fire. Shrub versus interspace microsites had no observed influence on seed bank composition in any desert. However, seed bank species richness was greater under shrubs in both warm deserts. Non‐native species were present in the seed banks of all deserts and some were particularly abundant in the burned sites. Despite the presence of native species in both burned and unburned seed banks, the presence of non‐native species suggests some degree of vulnerability to future disturbances because fire can create amplifying feedback with many non‐native plants. Our results highlight strong differences in fires' relationship with seed banks for warm and cold desert sites and lend insight into how fire relates to the composition and diversity of the seeds that play a fundamental role in future plant communities. [ABSTRACT FROM AUTHOR]

Many plant species exhibit strong seed dormancy. This attribute benefits the species’ long-term survival but can impede restoration when rapid establishment is required. Soaking seeds in gibberellic acid (GA3) can overcome dormancy and increase germination but this treatment may not be effective outside the laboratory. An easier and potentially more effective method to apply this hormone is to coat seeds with a GA3-impregnated polymer. Seed dormancy can also be mitigated by creating a favorable microsite with increased soil moisture. We compared the emergence and establishment of penstemon seeds coated with GA3 to those of uncoated seeds planted in shallow drill rows versus deep, U-shaped furrows. Overall, 6 times more Palmer’s penstemon (Penstemon palmeri; p < 0.01) and 21 times more thickleaf penstemon (P. pachyphyllus; p < 0.001) established when coated with GA3, but GA3 coating did not affect the establishment of firecracker penstemon (P. eatonii; p = 1). Establishment was higher from deep furrows than shallow rows (p < 0.001). These results indicate that GA3 seed coating and deep, U-shaped furrows may improve the restoration success of some native forbs by breaking dormancy and providing a favorable microsite. Land managers could use these techniques to restore native forbs in dry, disturbed areas.

As labour for manual tree planting becomes scarcer, regeneration costs are steadily increasing in Nordic forestry. Today's intermittently advancing tree planting machines provide excellent silvicultural results, but are expensive to operate because of poor productivity. In contrast, continuously advancing planting machines, thanks to high productivities, are increasingly being regarded as a solution to these runaway regeneration costs. The Silva Nova was a historical, continuously advancing tree planting machine with high productivity. However, Silva Nova's weaknesses included high labour costs (it required two operators) and the random nature of how it chose planting spots. In contrast, SuperSilva, a purely conceptual modernisation of Silva Nova, involves both automation and microsite identification to make the machine more efficient. We used discrete-event simulation to analyse the stocking rate and spatial distribution of tree planting with SuperSilva. The simulation results showed that introducing sensors for identifying suitable microsites will allow continuously advancing planting machines (like SuperSilva) to plant seedlings in a numerically and spatially adequate manner on moraine soils. Hence, these sensors will increase the competitiveness and versatility of tree planting machines. Unfortunately, such reliable and robust sensor technology (unaffected by a wide variety of operating conditions) is not yet commercially available.

Abstract Microsites created by soil‐disturbing animals are important landscape elements in arid environments. In the Pre‐Namib, dust‐bathing behavior of the near‐endemic Hartmann's mountain zebra creates unique rolling pits that persist in the landscape. However, the ecohydrological characteristics and the effects of those microsites on the vegetation and on organisms of higher trophic levels are still unknown. In our study, we characterized the soil grain size composition and infiltration properties of rolling pits and reference sites and recorded vegetation and arthropod assemblages during the rainy season of five consecutive years with different amounts of seasonal rainfall. We further used the excess green vegetation index derived from drone imagery to demonstrate the different green up and wilting of pits and references after a rainfall event. In contrast to the surrounding grassland, rolling pits had finer soil with higher nutrient content, collected runoff, showed a higher infiltration, and kept soil moisture longer. Vegetation in the rolling pits was denser, dominated by annual forbs and remained green for longer periods. The denser vegetation resulted in a slightly higher activity density of herbivorous arthropods, which in turn increased the activity density of omnivorous and predatory arthropods. In times of drought, the rolling pits could act as safe sites and refuges for forbs and arthropods. With their rolling pits, Hartmann's mountain zebras act as ecosystem engineers, contributing to the diversity of forb communities and heterogeneity of the landscape in the Pre‐Namib.

Improving post‐wildfire restoration of foundational plant species is crucial for conserving imperiled ecosystems. We sought to better understand the initial establishment of sagebrush (Artemisia sp.), a foundational shrubland species over a vast area of western North America, in the first 1–2 years post‐wildfire, a critical time period for population recovery. Field data from 460 sagebrush populations sampled across the Great Basin revealed several patterns. Sagebrush seedlings were uncommon in the first 1–2 years after fire, with none detected in 69% of plots, largely because most fires occurred in areas of low resistance to invasive species and resilience to disturbance (hereafter, R&R). Post‐fire aerial seeding of sagebrush dramatically increased seedling occupancy, especially in low R&R areas, which exhibited a 3.4‐fold increase in occupancy over similar unseeded locations. However, occupancy models and repeat surveys suggested exceptionally high mortality, as occupancy rates declined by as much as 50% between the first and second years after fire. We found the prevalence of "fertile island" microsites (patches beneath fire‐consumed sagebrush) to be the best predictor of seedling occupancy, followed by aerial seeding status, native perennial grass cover, and years since fire. In populations where no sagebrush seeding occurred, seedlings were most likely to occur in locations with a combination of high fertile island microsite cover and close proximity to a remnant sagebrush plant. These important attributes were only present in 13% of post‐fire locations, making them rare across the Great Basin. Finally, in the absence of fertile islands and remnant plants, seedling establishment was not observed in any unseeded areas, and rarely in seeded locations. Thus, local extirpation of sagebrush could have important, long‐term implications for sagebrush reestablishment following future fires if there are no mature individuals to leave behind fertile islands or serve as remnant individuals. These findings highlight the importance of landscape legacy effects and could help guide where and how big sagebrush restoration is conducted in the future. [ABSTRACT FROM AUTHOR]

Miller's witch-alder (Fothergilla milleri, Hamamelidaceae) is a newly described globally imperiled shrub that is known from disjunct populations in coastal Alabama, the panhandle of Florida, and one location in Georgia. Little is currently known about the natural history or ecology of the species. We conducted inventories of three populations of F. milleri in Alabama and Florida. A total of 3060 ramets were found; 45% were in one subpopulation ≤0.5 ha in area and 79% were in one population within an area of 4.5 ha. Low ramet counts in few locations makes the species particularly vulnerable to extinction due to stochastic events. Also, all seed capsules found within the surveys were infected by an aphid, which is possibly preventing sexual reproduction within the populations. Microsite habitat data indicated F. milleri grows in a unique transitional habitat between upland conifer forest and wetlands. The sites where extant populations of F. milleri inhabit tend to have acidic and well-drained soils with a high sand content. Further, many populations were under thick midstory vegetation. Thus, fire or other forms of removal may be needed to release those subpopulations before they may become shaded out. Lastly, a habitat suitability model was developed to better facilitate conservation efforts. However, only 0.5% of the study area was within the highest level of suitability. Fothergilla milleri is facing multiple threats that could lead to its extirpation from the wild, and direct and intense conservation action may be necessary to ensure F. milleri remains on the landscape. [ABSTRACT FROM AUTHOR]

Abstract Improving post‐wildfire restoration of foundational plant species is crucial for conserving imperiled ecosystems. We sought to better understand the initial establishment of sagebrush (Artemisia sp.), a foundational shrubland species over a vast area of western North America, in the first 1–2 years post‐wildfire, a critical time period for population recovery. Field data from 460 sagebrush populations sampled across the Great Basin revealed several patterns. Sagebrush seedlings were uncommon in the first 1–2 years after fire, with none detected in 69% of plots, largely because most fires occurred in areas of low resistance to invasive species and resilience to disturbance (hereafter, R&R). Post‐fire aerial seeding of sagebrush dramatically increased seedling occupancy, especially in low R&R areas, which exhibited a 3.4‐fold increase in occupancy over similar unseeded locations. However, occupancy models and repeat surveys suggested exceptionally high mortality, as occupancy rates declined by as much as 50% between the first and second years after fire. We found the prevalence of “fertile island” microsites (patches beneath fire‐consumed sagebrush) to be the best predictor of seedling occupancy, followed by aerial seeding status, native perennial grass cover, and years since fire. In populations where no sagebrush seeding occurred, seedlings were most likely to occur in locations with a combination of high fertile island microsite cover and close proximity to a remnant sagebrush plant. These important attributes were only present in 13% of post‐fire locations, making them rare across the Great Basin. Finally, in the absence of fertile islands and remnant plants, seedling establishment was not observed in any unseeded areas, and rarely in seeded locations. Thus, local extirpation of sagebrush could have important, long‐term implications for sagebrush reestablishment following future fires if there are no mature individuals to leave behind fertile islands or serve as remnant individuals. These findings highlight the importance of landscape legacy effects and could help guide where and how big sagebrush restoration is conducted in the future.

Fire regimes are changing in several regions of the world. In those regions, some exotic species may be better adapted to new regimes than the native species. This study focused on identifying the microsite characteristics associated with the occurrence of post-fire Eucalyptus globulus regeneration from seeds, outside the species native-range. This information is important in helping to assess the naturalization status of the species, to understand its invasion risk, and to manage wildlings in plantations. To characterize the establishment niche, pairs of microsites (sapling presence/absence) were sampled in four salvage-logged plantations of E. globulus two years after fire (20 pairs/plantation). Microsites of wildlings from three size classes and control microsites were established in one of these plantations (20 quartets) in order to characterize the recruitment niche and to assess ontogenic niche shifts. Two post-fire wildling cohorts were identified. The first emerged just after fire and was abundant. The second emerged after logging and was scarce, probably due to seed limitation. First-cohort wildlings were observed in microsites characterized by a high incidence of fire-related variables (charcoal, ash, increased soil pH and K). The aggregated distribution of these wildlings and their association with other species may indicate the existence of facilitative relationships and/or the exploitation of resource-rich patches. All these factors were relevant for first-cohort persistence and likely also for its establishment and recruitment. Second-cohort wildlings occurred in microsites where salvage-logging disturbance was evident, showing the importance of this disturbance for its emergence. Wildling size diversity was explained by the two recruitment events and by the asymmetrical competition between wildlings and adults. No niche shifts were detected. The high densities of E. globulus wildlings found established in burnt plantations indicated naturalization was in progress. The timing of major recruitment events and the phenology of the species should be considered for monitoring this regeneration and scheduling control interventions, if required. [ABSTRACT FROM AUTHOR]

Thermokarst disturbance in permafrost landscapes is likely to increase across the tundra biome with climate warming, resulting in changes to topography, vegetation, and biogeochemical cycling. Tundra shrubs grow on permafrost, but shrub–thermokarst relationships are rarely studied in detail. Since the 1980s, Alaska's North Slope has experienced increased thermokarst activity, including retrogressive thaw slumps (RTSs) on hillslopes. Within decades, RTSs near Toolik Lake, Alaska, were colonized by tall (≥0.5 m) deciduous shrubs. We used dendrochronology methods on 66 shrubs (182 stem cross sections) representing dominant deciduous species: willows (Salix pulchra and S. glauca) and dwarf birch (Betula nana) at two RTS chronosequences on Alaska's North Slope comprising seven sites, to quantify thermokarst and climate effects (25 years of temperature and precipitation records) on shrub secondary growth (i.e., annual rings) in RTS‐disturbed and undisturbed moist acidic tussock (MAT) tundra. Across species, average growth ring widths were two times wider for shrubs in RTSs than in MAT, and ring widths decreased with RTS age. A 1°C June temperature increase was associated with 2% wider rings across species and sites, but shrubs showed marginal growth in warmer summers, supporting tundra‐wide shrub climate sensitivity studies. A 4.5% average ring width increase per 1 mm of previous year's September precipitation was seen in shrubs in mid‐successional RTSs, suggesting protective effects of early snowfall in RTSs versus open tundra. Retrogressive thaw slump age category explained 47% and 30% of average ring width variance of willows and dwarf birch, respectively, in linear mixed‐effects models. Climate variables explained 2% average ring width variance across species. Our results suggest that RTS exerts strong successional effects on tundra shrub growth. Climate effects appear to show weaker synoptic patterns across the study area. Retrogressive thaw slumps will likely contribute to tundra greening where RTS activity is increasing. [ABSTRACT FROM AUTHOR]

Context. Conservation translocations are increasingly being used in the management of rare plants, yet have low success in maintaining populations through recruitment. Aims. We investigated whether the survival of translocated plants, recruitment and, therefore, cost effectiveness, can be improved by selecting optimal microsites for both adults and seedlings. Methods. Caladenia colorata plants propagated symbiotically with Serendipita australiana (n = 735) were introduced to four sites where the pollinator was present and vegetation matched wild populations. Plant demography was monitored over 6 years. The relationship between microsite variables and measures of orchid survival, re-emergence, flowering and recruitment were analysed with generalised linear mixed-effects models. We then estimated potential improvement in emergence and recruitment, if microsite selection was optimised. Key results. A total of 77% of plants survived translocation, and populations grew by 84% through recruitment (n = 615). Survival was positively associated with cover of leaf litter, graminoids and cryptogams. Recruitment was positively correlated with soil moisture. The majority of recruitment was within 5 cm of adult C. colorata plants. The potential improvement by selecting favourable microsites increased adult survival by up to 8% and recruitment by 10-40%. Conclusions. Incorporating both the germination niche and adult plant niche within plant translocations more broadly could significantly improve long-term population persistence and the utilisation of conservation funding. Implications. Our results are directly applicable to 58 endangered Caladenia species in the subgenus Calonema, owing to their shared mycorrhizal association with S. australiana. Furthermore, our results are applicable to all plant translocations as understanding germination niche and microhabitat requirements is likely to improve success overall. [ABSTRACT FROM AUTHOR]

Abstract Thermokarst disturbance in permafrost landscapes is likely to increase across the tundra biome with climate warming, resulting in changes to topography, vegetation, and biogeochemical cycling. Tundra shrubs grow on permafrost, but shrub–thermokarst relationships are rarely studied in detail. Since the 1980s, Alaska's North Slope has experienced increased thermokarst activity, including retrogressive thaw slumps (RTSs) on hillslopes. Within decades, RTSs near Toolik Lake, Alaska, were colonized by tall (≥0.5 m) deciduous shrubs. We used dendrochronology methods on 66 shrubs (182 stem cross sections) representing dominant deciduous species: willows (Salix pulchra and S. glauca) and dwarf birch (Betula nana) at two RTS chronosequences on Alaska's North Slope comprising seven sites, to quantify thermokarst and climate effects (25 years of temperature and precipitation records) on shrub secondary growth (i.e., annual rings) in RTS‐disturbed and undisturbed moist acidic tussock (MAT) tundra. Across species, average growth ring widths were two times wider for shrubs in RTSs than in MAT, and ring widths decreased with RTS age. A 1°C June temperature increase was associated with 2% wider rings across species and sites, but shrubs showed marginal growth in warmer summers, supporting tundra‐wide shrub climate sensitivity studies. A 4.5% average ring width increase per 1 mm of previous year's September precipitation was seen in shrubs in mid‐successional RTSs, suggesting protective effects of early snowfall in RTSs versus open tundra. Retrogressive thaw slump age category explained 47% and 30% of average ring width variance of willows and dwarf birch, respectively, in linear mixed‐effects models. Climate variables explained 2% average ring width variance across species. Our results suggest that RTS exerts strong successional effects on tundra shrub growth. Climate effects appear to show weaker synoptic patterns across the study area. Retrogressive thaw slumps will likely contribute to tundra greening where RTS activity is increasing.

This paper describes a study on the translocation and reestablishment of the federally endangered species Lupinus nipomensis (Fabaceae) and aims to better understand the effect of various biotic and abiotic conditions on plant growth.

Aim: Climate warming is expected to drive upward and poleward shifts at the leading edge of tree species ranges. Disturbance has the potential to accelerate these shifts by altering biotic and abiotic conditions, though this potential is likely to vary by disturbance type. In this study, we assessed whether recent wildfires and spruce beetle outbreaks promoted upward range expansion of trembling aspen. Location: The San Juan Mountains of southern Colorado, USA (37°34′–37°50′N, 106°49′–107°21′W). Taxon: Populus tremuloides. Methods: We used aerial imagery to determine the upper elevational limit of adult aspen and conducted seedling surveys at and above this upper limit in burned and unburned areas, which had already incurred high canopy mortality due to spruce bark beetle (Dendroctonus rufipennis) outbreaks. We compared characteristics of burned versus unburned bark beetle‐killed sites and assessed microsite conditions related to aspen seedling establishment using generalized linear models and interaction indices. Results: Aspen seedling establishment occurred upslope of its previous range within burns, but not in unburned areas, despite severe beetle‐driven canopy mortality across all sites before the fire. Aspen seedling establishment was associated more with the light and mineral soil created by fire than the presence of nearby seed sources. Aspen seedlings were associated with nurse objects such as logs and rocks at the highest elevations, where these objects may ameliorate a range of stressors associated with the high elevation range boundary. Main conclusions: Not all disturbance types are equal in promoting tree species migrations at the leading edge. Range shifts can be highly localized, and microsites are important for driving local range expansions in transitional environments. The mosaic of future disturbances across the landscape will drive forest compositional shifts, depending on the disturbance types and the species they promote. [ABSTRACT FROM AUTHOR]

The extant literature has indicated that interacting with customers to obtain their input during new service development projects is key to developing successful new services. However, the literature has focused mostly on the use of traditional face-to-face interaction with the customers. Lately, a growing trend among many B2B firms is to collaborate with the customers via various social media platforms. Yet, the literature has overlooked the use of social media as a key mode of interaction for obtaining customer input for new service development. Also, the question, how to use social media for customer interaction alongside other traditional modes of interactions has remained unanswered. Therefore, the objective of this research is to investigate the use of social media along with the traditional modes of customer interaction for developing new B2B financial services. To achieve the above research objective, we developed a multi-phase, longitudinal and robust qualitative research design. We collected data from several new service development projects being pursued by a large financial service firm in India. First, we interviewed 17 managers, who were in charge of the new service projects in the firm. In addition, we interviewed 92 customers that were involved in interaction with the managers during the new service development process. During and after the interviews, several documents and archival records were consulted to triangulate the data provided by the respondents. We also ethnographically observed social media interactions among customers and managers for about 11 months. We analyzed the data using open, axial, and selective coding and maintained a robust case study database. The findings highlight a promising new facet of customer interaction in which both traditional modes and social media can be effectively combined for obtaining rich customer input thereby increasing the odds for developing successful new services in the B2B financial services industry. The findings also suggest that social media alone cannot help a firm obtain rich customer input because social media interactions produce mainly corroborative information. Thus, to develop innovative new services a firm must combine various modes of interaction, both traditional modes and social media. The article has implications for the literature related to B2B services industry. Particularly, the findings of this study advance the current knowledge of social media interaction and new service development in B2B firms. We also contribute to the important but relatively sparse literature treating social media as a mode of customer interaction. Our study also advances the literature of new service development and global marketing by studying the new service development process in the emerging market of India. Customer interaction should be a key element in a firm's new service development activity. This article has proposed several customer interaction strategies in order to outline a course of action that the service managers can apply in their quest for successful new services. In particular, our research offers actionable guidance to the managers and companies in the emerging markets aiming to use the strategy of customer interaction and leveraging the power of social media for their NSD programs. Many B2B financial service firms in the emerging markets will find the strategy and process described in this research useful for developing successful new services for their business customers. This study reflects the current academic and practitioner interest in the emerging role of social media particularly in the B2B context. Arguably, this is the first study that bridges the gap between research on social media and customer interaction for the purpose of developing new B2B services. Particularly, combining the traditional modes of interaction with social media interaction is a unique contribution of this study. The research also adds to the emergent research theme of customer interaction for developing new B2B services in the emerging market. Overall, this study offers new insights into the current understanding of customer interaction against the backdrop of increasing digitization of various business functions including new service development in the B2B context. [ABSTRACT FROM AUTHOR]

Successful plant recruitment is crucial for maintaining forest ecosystems, but knowledge of the responses of early life stages of tropical montane tree species to complex environmental factors is still limited across the Himalayas. Vegetation was surveyed along an altitudinal gradient (2450–3070 m) in six altitudinal bands in a tropical montane forest of Myanmar. We examined the effects of microclimate, soil, and microsite conditions on seedling and sapling recruitment in three dominant tree species (Quercus semecarpifolia, Rhododendron arboreum, and Symplocos lucida). We found that densities of R. arboreum and Q. semecarpifolia were higher in high and mid-altitudinal bands (2800–3000 m), whereas density of S. lucida was higher in lower altitudinal bands (2600–2700 m). Seedlings showed better recruitment in humid conditions and more sensitive to soil properties than saplings. R. arboreum and S. lucida preferred debris microsites, followed by shrub and grass microsites, whereas Q. semecarpifolia showed no significant microsite preference. Seedling recruitment mainly depended on soils and microsites, whereas sapling recruitment depended on microclimate and altitude. The study provides information on species-specific preferences and responses of montane tree species to complex environmental factors, which may contribute to restoration and sustainable forest conservation. [ABSTRACT FROM AUTHOR]

Microsites created by soil‐disturbing animals are important landscape elements in arid environments. In the Pre‐Namib, dust‐bathing behavior of the near‐endemic Hartmann's mountain zebra creates unique rolling pits that persist in the landscape. However, the ecohydrological characteristics and the effects of those microsites on the vegetation and on organisms of higher trophic levels are still unknown. In our study, we characterized the soil grain size composition and infiltration properties of rolling pits and reference sites and recorded vegetation and arthropod assemblages during the rainy season of five consecutive years with different amounts of seasonal rainfall. We further used the excess green vegetation index derived from drone imagery to demonstrate the different green up and wilting of pits and references after a rainfall event. In contrast to the surrounding grassland, rolling pits had finer soil with higher nutrient content, collected runoff, showed a higher infiltration, and kept soil moisture longer. Vegetation in the rolling pits was denser, dominated by annual forbs and remained green for longer periods. The denser vegetation resulted in a slightly higher activity density of herbivorous arthropods, which in turn increased the activity density of omnivorous and predatory arthropods. In times of drought, the rolling pits could act as safe sites and refuges for forbs and arthropods. With their rolling pits, Hartmann's mountain zebras act as ecosystem engineers, contributing to the diversity of forb communities and heterogeneity of the landscape in the Pre‐Namib. [ABSTRACT FROM AUTHOR]

Abstract The altitudinal patterns of lichen communities in altitudinal gradients are very variable. The changes that occur along the mountains depend on climatic factors but also on microsite variables such as substrate type and aspect. The effect of altitude and aspect on richness, cover and composition of saxicolous lichens communities along an elevation gradient in extra Andean mountains from the central-west of Argentina was studied. Rock outcrops on the north and south aspect of three mountain summits distributed between 2,500 and 4,500 m.a.s.l. were sampled. Lichen species present in a 20 × 20 cm square were identified and the relative cover was measured using digital photography. Richness, cover and composition were analyzed through linear models and multivariate analysis. Fifty-eight saxicolous lichen species were identified between the three sites. Richness and cover were maximum at middle altitude. Also compositional differences among communities of each mountain summit were found. Finally, the effect of the aspect was significant at lower altitudes for cover and composition.

Factors affecting successional processes are critical determinants of the structural and compositional changes in a plant community. The present study examines the role of plant traits, such as seed size and dispersal mode, habitat factors such as canopy closure, leaf litter, soil moisture, disturbance, fire frequency, and landscape forest cover, in arrival and establishment of tree species in the oak-pine forests of the Western Himalayas. For this, we compared the regeneration, abundance, and composition of tree species in pine forests (pioneer stage) with that in oak-dominated hardwood forests (climax stage). The microsite factors and landscape forest cover varied significantly between the two stages. While species diversity was comparable across seedling, sapling, and pole stages, density of regenerating individuals was relatively lower in oak forest sites. The extent of overlap in species composition between oak and pine forest sites was also found to be low for both regeneration and adult stages. The amount of forest cover surrounding the study sites (landscape forest cover) did not significantly impact regeneration. Instead, factors related to establishment were determined to be more important. Regeneration density decreased with an increase in canopy closure (light environment) and litter depth, implying their crucial role in driving the successional trajectories. When plant traits were considered, all three regeneration stages of large-seeded and animal-dispersed species were of comparable densities in pine and oak forests, suggesting an absence of dispersal or arrival limitation. However, anthropogenic disturbance was found to negatively impact density of zoochorous species while fire frequency negatively influenced the diversity of large-seeded species. Control of extractive pressures, reducing incidence of fire, and retention of protected oak stands may be necessary to enable regeneration of zoochorous and of large-seeded species and thereby, natural succession to oak-dominated hardwood forest in this human-dominated landscape. • Successional trajectory largely dependent on microsite factors. • No evidence of dispersal limitation in oak and pine forests. • Disturbance negatively affected regeneration of zoochorous species. [ABSTRACT FROM AUTHOR]

As labour for manual tree planting becomes scarcer, regeneration costs are steadily increasing in Nordic forestry. Today's intermittently advancing tree planting machines provide excellent silvicultural results, but are expensive to operate because of poor productivity. In contrast, continuously advancing planting machines, thanks to high productivities, are increasingly being regarded as a solution to these runaway regeneration costs. The Silva Nova was a historical, continuously advancing tree planting machine with high productivity. However, Silva Nova's weaknesses included high labour costs (it required two operators) and the random nature of how it chose planting spots. In contrast, SuperSilva, a purely conceptual modernisation of Silva Nova, involves both automation and microsite identification to make the machine more efficient. We used discrete-event simulation to analyse the stocking rate and spatial distribution of tree planting with SuperSilva. The simulation results showed that introducing sensors for identifying suitable microsites will allow continuously advancing planting machines (like SuperSilva) to plant seedlings in a numerically and spatially adequate manner on moraine soils. Hence, these sensors will increase the competitiveness and versatility of tree planting machines. Unfortunately, such reliable and robust sensor technology (unaffected by a wide variety of operating conditions) is not yet commercially available. [ABSTRACT FROM AUTHOR]

Increasing temperatures and drought in desert ecosystems are predicted to cause decreased vegetation density combined with barren ground expansion. It remains unclear how nutrient availability, microbial diversity, and the associated functional capacity vary between the vegetated canopy and gap soils. The specific aim of this study was to characterize canopy versus gap microsite effect on soil microbial diversity, the capacity of gap soils to serve as a canopy soil microbial reservoir, nitrogen (N)-mineralization genetic potential (ureC gene abundance) and urease enzyme activity, and microbial-nutrient pool associations in four arid-hyperarid geolocations of the western Sonoran Desert, Arizona, United States. Microsite combined with geolocation explained 57% and 45.8% of the observed variation in bacterial/archaeal and fungal community composition, respectively. A core microbiome of amplicon sequence variants was shared between the canopy and gap soil communities; however, canopy soils included abundant taxa that were not present in associated gap communities, thereby suggesting that these taxa cannot be sourced from the associated gap soils. Linear mixed-effects models showed that canopy soils have significantly higher microbial richness, nutrient content, and organic N-mineralization genetic and functional capacity. Furthermore, ureC gene abundance was detected in all samples, suggesting that ureC is a relevant indicator of N mineralization in deserts. Additionally, novel phylogenetic associations were observed for ureC, with the majority belonging to Actinobacteria and uncharacterized bacteria. Thus, key N-mineralization functional capacity is associated with a dominant desert phylum. Overall, these results suggest that lower microbial diversity and functional capacity in gap soils may impact ecosystem sustainability as aridity drives open-space expansion in deserts. [ABSTRACT FROM AUTHOR]

Question: Fine‐scale environmental heterogeneity supports floristic diversity in forest ecosystems by increasing the variety of niches available for specialist species. Although recognized in concept, the niche function of microsites has not been well documented. This study tests whether microsites at the base of large trees are physically or edaphically distinct from the forest floor in general, and whether forest herb composition responds to this form of heterogeneity. Location: Long‐established deciduous forest in the unglaciated section of southeastern Ohio, USA. Methods: We measured fourteen herb‐relevant environmental variables and censused the herb flora at the bases of large trees and in control plots away from trees. Results: Moss cover, exposed root cover, and canopy openness were significantly greater at large‐tree bases than in control plots, while leaf litter cover was significantly lower at tree bases. Species richness and stem density were higher in tree‐base plots, and multivariate species composition differed significantly between tree bases and controls. Two species, Eurybia divaricata and Cardamine douglassii, were significantly more abundant at tree bases. Gradients of litter cover and root exposure accounted for the compositional difference between tree bases and controls. Coarse woody debris, moss cover, and soil root fraction accounted for differences orthogonal to the tree‐base/control axis indicating heterogeneity within tree‐base microsites. Conclusions: Tree bases are physically distinct microsites which support diversity by providing niches to some forest herb species. Because availability of such microsites is linked to tree size, this aspect of community diversity appears to be controlled by stand development. [ABSTRACT FROM AUTHOR]

The altitudinal patterns of lichen communities in altitudinal gradients are very variable. The changes that occur along the mountains depend on climatic factors but also on microsite variables such as substrate type and aspect. The effect of altitude and aspect on richness, cover and composition of saxicolous lichens communities along an elevation gradient in extra Andean mountains from the central-west of Argentina was studied. Rock outcrops on the north and south aspect of three mountain summits distributed between 2,500 and 4,500 m.a.s.l. were sampled. Lichen species present in a 20 x 20 cm square were identified and the relative cover was measured using digital photography. Richness, cover and composition were analyzed through linear models and multivariate analysis. Fifty-eight saxicolous lichen species were identified between the three sites. Richness and cover were maximum at middle altitude. Also compositional differences among communities of each mountain summit were found. Finally, the effect of the aspect was significant at lower altitudes for cover and composition. [ABSTRACT FROM AUTHOR]

The mobility and bioavailability of phosphate in paddy soils are closely coupled to redox-driven Fe-mineral dynamics. However, the role of phosphate during Fe-mineral dissolution and transformations in soils remains unclear. Here, we investigated the transformations of ferrihydrite and lepidocrocite and the effects of phosphate pre-adsorbed to ferrihydrite during a 16-week field incubation in a flooded sandy rice paddy soil in Thailand. For the deployment of the synthetic Fe-minerals in the soil, the minerals were contained in mesh bags either in pure form or after mixing with soil material. In the latter case, the Fe-minerals were labeled with 57 Fe to allow the tracing of minerals in the soil matrix with 57 Fe Mössbauer spectroscopy. Porewater geochemical conditions were monitored, and changes in the Fe-mineral composition were analyzed using 57 Fe Mössbauer spectroscopy and/or X-ray diffraction analysis. Reductive dissolution of ferrihydrite and lepidocrocite played a minor role in the pure mineral mesh bags, while in the 57 Fe-mineral-soil mixes more than half of the minerals was dissolved. The pure ferrihydrite was transformed largely to goethite (82-85%), while ferrihydrite mixed with soil only resulted in 32% of all remaining 57 Fe present as goethite after 16 weeks. In contrast, lepidocrocite was only transformed to 12% goethite when not mixed with soil, but 31% of all remaining 57 Fe was found in goethite when it was mixed with soil. Adsorbed phosphate strongly hindered ferrihydrite transformation to other minerals, regardless of whether it was mixed with soil. Our results clearly demonstrate the influence of the complex soil matrix on Fe-mineral transformations in soils under field conditions and how phosphate can impact Fe oxyhydroxide dynamics under Fe reducing soil conditions.

Coastal sand dunes near the Baltic Sea are a dynamic environment marking the boundary between land and sea and oftentimes covered by Scots pine (Pinus sylvestris L.) forests. Complex climate-environmental interactions characterize these ecosystems and largely determine the productivity and state of these coastal forests. In the face of future climate change, understanding interactions between coastal tree growth and climate variability is important to promote sustainable coastal forests. In this study, we assessed the effect of microsite conditions on tree growth and the temporal and spatial variability of the relationship between climate and Scots pine growth at nine coastal sand dune sites located around the south Baltic Sea. At each site, we studied the growth of Scots pine growing at microsites located at the ridge and bottom of a dune and built a network of 18 ring-width and 18 latewood blue intensity chronologies. Across this network, we found that microsite has a minor influence on ring-width variability, basal area increment, latewood blue intensity, and climate sensitivity. However, at the local scale, microsite effects turned out to be important for growth and climate sensitivity at some sites. Correlation analysis indicated that the strength and direction of climate-growth responses for the ring-width and blue intensity chronologies were similar for climate variables over the 1903–2016 period. A strong and positive relationship between ring-width and latewood blue intensity chronologies with winter-spring temperature was detected at local and regional scales. We identified a relatively strong, positive influence of winter-spring/summer moisture availability on both tree-ring proxies. When climate-growth responses between two intervals (1903–1959, 1960–2016) were compared, the strength of growth responses to temperature and moisture availability for both proxies varied. More specifically, for the ring-width network, we identified decreasing temperature-growth responses, which is in contrast to the latewood blue intensity network, where we documented decreasing and increasing temperature-growth relationships in the north and south respectively. We conclude that coastal Scots pine forests are primarily limited by winter-spring temperature and winter-spring/summer drought despite differing microsite conditions. We detected some spatial and temporal variability in climate-growth relationships that warrant further investigation.

Copyright of Journal of Field Ornithology is the property of Resilience Alliance 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.)

Evaluation of the spatial distribution of 2 ecologically similar, but different, in terms of their spatial ranges, earthworm species, D. octaedra and D. attemsi, in the belt forests of northwestern Caucasus were based on our own natural data and using geographic information system (GIS) modeling of modern potential distributions. The quantitative records of earthworms were collected in beech, deciduous, dark coniferous, coniferous-deciduous, and pine forests (1028 geographic locations). Of the most important microsites inhabited by the epigeic earthworms, 2 (plant litter and deadwood) were examined. It was demonstrated that there was high correlation of the 2 species with the humidity of the habitat and the presence of deadwood at different stages of decomposition, especially for D. attemsi, which lives mainly in deadwood in all of the forest types. The high correlation of these species to coniferous-deciduous forests and dark coniferous forests was demonstrated on both the basis of the field data analysis and the GIS modeling results. [ABSTRACT FROM AUTHOR]

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

A critical stage in the establishment of new individuals is seedling emergence and litter is a main factor affecting this stage. Recent research found that adults of Chuquiraga avellanedae are over-dispersed. Among several mechanisms, this pattern might be due to the negative influences of adults on seedlings through root competition. We performed field and glasshouse experiments to evaluate (i) the effects of C. avellanedae leaf litter and root presence on the emergence of conspecific seedlings, and (ii) the effects of leaf litter type (C. avellanedae litter, inert litter, no litter) and seed burial depth (seed at the surface or buried) on the emergence of C. avellanedae and Nassella tenuis (dominant grass) seedlings. The field experiment demonstrated root competition from adult plants on shrub seedlings, reducing seedling emergence. However, the effect of root competition did not differ between microsites (under-shrubs vs. between-shrubs). We dismiss the effect of allelopathy because inert litter (i.e., plastic leaves) had the same negative effect as C. avellanedae litter, indicating a mechanical effect. The glasshouse experiment revealed a species-specific response of seedling emergence. C. avellanedae litter limits the emergence of conspecific seedlings but was neutral with regard to the emergence of grass seedlings (N. tenuis). No differences in root competition between microsites and reduction of shrub seedlings by litter suggest that the over-dispersed pattern found for C. avellanedae is caused, at least partially, by litter effects on seedling emergence. [ABSTRACT FROM AUTHOR]

Avian responses to high environmental temperatures include retreating to cooler microsites and/or increasing rates of evaporative heat dissipation via panting, both of which may affect foraging success. We hypothesized that behavioural trade-offs constrain the maintenance of avian body condition in hot environments, and tested predictions arising from this hypothesis for male Southern Yellow-billed Hornbills (Tockus leucomelas) breeding in the Kalahari Desert. Operative temperatures experienced by the hornbills varied by up to 13 °C among four microsite categories used by foraging males. Lower prey capture rates while panting and reductions associated with the occupancy of off-ground microsites, resulted in sharp declines in foraging efficiency during hot weather. Consequently, male body mass (Mb) gain between sunrise and sunset decreased with increasing daily maximum air temperature (Tmax), from ~ 5% when Tmax < 25 °C to zero when Tmax = 38.4 °C. Overnight Mb loss averaged ~ 4.5% irrespective of Tmax, creating a situation where nett 24-h Mb loss approached 5% on extremely hot days. These findings support the notion that temperature is a major determinant of body condition for arid-zone birds. Moreover, the strong temperature dependence of foraging success and body condition among male hornbills provisioning nests raises the possibility that male behavioural trade-offs translate into equally strong effects of hot weather on female condition and nest success. Our results also reveal how rapid anthropogenic climate change is likely to substantially decrease the probability of arid-zone birds like hornbills being able to successfully provision nests while maintaining their own condition. [ABSTRACT FROM AUTHOR]

Wildlife monitoring is essential for assessing the size of species of conservation or management concern. Wildlife monitoring could be undertaken by selected volunteers when limited resources are available. Here, we study the sources of variation in the detectability of red fox scats and to improve the monitoring of the species by means of volunteers who were briefly trained. We selected nine transects to experimentally evaluate the differences in red fox scat detectability between observers, microsite, and scat abundance. Scats were deposited in five microsites, where we simulate low, medium, and high fox scat abundance. We tested the proposed effects by using GLMM analysis incorporating observer effect as a random factor. Our results indicated effects on scat detectability of observer identity and microsite type. We did not observe the effects of scat abundance on detectability of scats. Detectability was lower for scats located in the middle of the transect and on the rocks. We conclude that large-scale red foxes surveys might be conducted using volunteers, but due to the moderate differences detected among observers should be minimized using a training period. [ABSTRACT FROM AUTHOR]

Aims: In many mixed grass-shrub ecosystems, increased shrub biomass tends to promote overall carbon storage, but the distribution of carbon pools may be complicated by disturbances such as wildfires. We investigated the spatial distribution of surface soil organic carbon (SOC) and its relative contribution from grasses and shrubs after fires in a grass-shrub transition zone in the northern Chihuahuan Desert, USA.Methods: We used a prescribed fire to create a burned treatment, then collected soil and plant samples. The biogeochemical approaches, geostatistical analyses, and carbon partitioning analyses were used to quantify the SOC and soil δ13C spatial patterns.Results: Before the prescribed fire, up to 98% of the spatial dependence of SOC was autocorrelated at a distance of 1.91 m, corresponding to the approximate average shrub canopy diameter, but the spatial dependence dropped to 81% at a larger autocorrelation distance (3.74 m) two windy seasons after the fire. C4 grasses and C3 shrubs contributed approximately equal amounts of carbon to the surface SOC pool before the prescribed fire. However, C4 grasses became the dominant source of SOC two windy seasons following the fire. For individual microsites, a substantially increased proportion of SOC was derived from C4 grasses at the shrub microsites following the fire.Conclusions: The higher proportion of C4 grasses-derived SOC at the shrub microsites post-fire suggests that SOC may have preferred pathways to move among different microsites following fire disturbance. The distinct spatial distribution patterns of δ13C, and the increased contribution of SOC from grasses may be explained by the rapid recovery of grasses following the fire. Overall, our results provide insights into how fire might be used as a management tool to alter soil carbon pools in the context of shrub encroachment. [ABSTRACT FROM AUTHOR]

Abstract Nitrification inhibitor 3,4-dimethylpyrazole phosphate (DMPP) could be used to reduce nitrogen (N) loss and improve N use efficiency in agroecosystems. However, the DMPP effect on N dynamics at the microscale remains largely unknown. A microcosm experiment was conducted to evaluate the effects of DMPP and fertilizer application method on N fate, including 15NH 4 +-N, (15NO 3 −+15NO 2 −)-N, MB15N and N losses at the centimeter-scale. The isotope labelled 15N-urea was applied to soil with or without DMPP. Two fertilizer application methods were compared, including mixed with soil (mix-application) or concentrated on the soil surface (spot-application). After 28 days of incubation at 28 °C, DMPP amended with urea significantly increased soil pH and 15NH 4 +-N concentrations but decreased (15NO 3 −+15NO 2 −)-N concentrations in both horizontal and vertical directions compared with urea application alone. Such effect was more obvious within 0–2 cm and weakened with increasing distance from the fertilizer zone. DMPP addition significantly increased N losses compared with urea application alone, which is mainly due to the increased ammonia volatilization caused by high pH and NH 4 + concentrations. The application method of urea and DMPP also had different effects on N performance, depending on the distance and spatial directions of microsites. And the N losses in the mix-application treatment (32%) were significantly lower than in the spot-application treatment (37%) when urea was applied alone. We concluded that DMPP addition significantly slowed down nitrification processes, and urea mixed with soil is better than concentrated on the soil surface in reducing N losses when urea was applied alone. Highlights • DMPP increased NH 4 +-N but decreased (NO 3 − + NO 2 −)-N concentrations at the microscale. • Nitrification inhibition was more evident within 0–2 cm from fertilization zone. • The efficiency of DMPP was weakened with the increasing distance. • Urea mixed with soil was better than spot on the soil surface in reducing N loss. [ABSTRACT FROM AUTHOR]