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Autotrophic and heterotrophic organisms require resources in stoichiometrically balanced ratios of carbon (C) to nutrients, the demand for which links organismal and ecosystem-level biogeochemical cycles. In soils, the relative availability of C and nitrogen (N) also defines the strength of competition for ammonium between autotrophic nitrifiers and heterotrophic decomposers, which may influence the coupled dynamics between N mineralization and nitrification. Here, we use data from the publicly available US National Science Foundation funded Long Term Ecological Research (LTER) network to evaluate the influence of soil C concentration on the relationship between net nitrification and net N mineralization. We found that soil C availability constrains the fraction of mineralized N that is ultimately nitrified across the continental gradient, contributing to reduced rates of nitrification in soils with high C concentrations. Nitrate, which is produced by nitrification, is a highly mobile ion that easily leaches to aquatic ecosystems or denitrifies into the greenhouse gas nitrous oxide (N2O). Understanding the connection between soil C concentration and soil N transformations is thus important for managing potential ecosystem N losses, understanding the biogeochemical constraints of these losses, and accurately representing coupled C-N dynamics in ecosystem models. [ABSTRACT FROM AUTHOR]

Net ecosystem carbon balance is a comprehensive assessment of ecosystem function that can test restoration effectiveness. Coastal peatlands are globally important carbon sinks that are vulnerable to carbon loss with saltwater intrusion. It is uncertain how wetland carbon stocks and fluxes change during freshwater restoration following exposure to saltwater and elevated nutrients. We restored freshwater to sawgrass (Cladium jamaicense) peat monoliths from freshwater marshes of the Everglades (Florida, U.S.A.) that had previously been exposed to elevated salinity (approximately9 ppt) and phosphorus (P) loading (1 g P m−2 year−1) in wetland mesocosms. We quantified changes in water and soil physicochemistry, plant and soil carbon and nutrient standing stocks, and net ecosystem productivity during restoration. Added freshwater immediately reduced porewater salinity from >8 to approximately 2 ppt, but elevated porewater dissolved organic carbon persisted. Above‐ and belowground biomass, leaf P concentrations, and instantaneous rates of gross ecosystem productivity (GEP) and ecosystem respiration (ER) remained elevated from prior added P. Modeled monthly GEP and ER were higher in marshes with saltwater and P legacies, resulting in negative net ecosystem productivities that were up to 12× lower than controls. Leaf litter breakdown rates and litter P concentrations were 2× higher in marshes with legacies of added saltwater and P. Legacies of saltwater and P on carbon loss persisted despite freshwater restoration, but recovery was greatest for freshwater marshes exposed to saltwater alone. Our results suggest that restoration in nutrient‐limited freshwater wetlands exposed to saltwater intrusion and nutrient enrichment is a slow process. [ABSTRACT FROM AUTHOR]

Spatial synchrony is the correlation between the temporal dynamics of local populations. This pattern may be driven by spatially correlated environmental variation (i.e., Moran effect), dispersal and trophic interactions. Investigating geographic patterns of synchrony can help disentangle the relative importance of these drivers.Using fish abundance data from long‐term ecological research (17 years) in the Upper Paraná River floodplain, we studied the relative roles of dispersal distance, density dependence differences, and environmental synchrony in determining spatial synchrony of the most common species in this floodplain. We also investigated the geography of spatial synchrony by estimating modularity and site‐level contributions to synchrony and anti‐synchrony networks.We found positive spatial synchrony for most species, but levels were relatively low. For most species, our explanatory matrices were poorly related to spatial synchrony. We detected modular structures in some species networks, which reflected complex spatial patterns in synchrony. We also detected sites with high importance to spatial synchrony patterns that could be managed to increase metapopulation stability.The variable levels of spatial synchrony for fish species in the Upper Paraná River floodplain implies the need to monitor several sites to understand their dynamics in this region. Also, some migratory species of high importance to regional fisheries, such as Prochilodus lineatus, may deserve special monitoring attention due to the increased regional extinction risk associated with their high levels of spatial synchrony.Finally, we speculate that hydrological manipulation from upstream reservoirs should consider the timing of water releases to avoid spatially correlated population declines. [ABSTRACT FROM AUTHOR]

Fire shapes ecological diversity, but its influence on bird communities is poorly understood. Fire is often considered crucial to management of savanna systems. Here, we assess effects of fire on bird species richness and density after a wildfire in September 2021, in an arid South African savanna where fire is infrequent. Point counts initially surveyed in 2004 now occurred in burnt and unburnt habitats, and were revisited five times across seasons from December 2021 to January 2023. This enabled identification of interaction effects of change over time and with fire from linear models using site and survey as predictor variables in a Before-After Control-Impact (BACI) framework. Patterns of bird species richness were explored using subsets of repeated points and those of summer to autumn surveys. To explore fire impacts on bird density, we used 'Distance Sampling' using additional surveys. Although total species richness during counts did not differ between survey periods and burnt and unburnt areas, densities of all birds were ca. 50% higher in unburnt veld relative to burnt, with this difference driven mostly by granivores. Three of 24 common species were significantly negatively influenced by fire. Fires may profoundly affect this arid zone bird community, a finding that would be overlooked if only species richness had been considered, and densities not accounted for. Fire, although potentially positive for biodiversity in mesic savannas, may negatively impact multiple taxa in arid savannas, which have a very different evolutionary and ecological history to that of more mesic savannas. These differences must be considered in management strategies. • Massive wildfire impact on avian communities in arid savanna: Bird density varied, but species richness remained unchanged in burnt vs. unburnt areas. • Granivorous species were negatively impacted by the fire, indicating the importance of considering dietary guilds alongside species richness when assessing fire effects. • While species richness alone may not reflect the true ecological effects of fire, turnover in species composition was observed, suggesting wildfire events in arid savanna's are subtle yet profound. [ABSTRACT FROM AUTHOR]

The study of ecosystem processes over multiple scales of space and time is often best achieved using comparable data from multiple sites. Yet, long-term ecological observatories have often developed their own data collection protocols. Here, we address this problem by proposing a set of ecological protocols suitable for widespread adoption by the ecological community. Scientists from the European ecological research community prioritized terrestrial ecosystem parameters that could benefit from a more consistent approach to data collection within the resources available at most long-term ecological observatories. Parameters for which standard methods are in widespread use, or for which methods are evolving rapidly, were not selected. Protocols were developed by domain experts, building on existing methods where possible, and refined through a process of field testing and training. They address above-ground plant biomass; decomposition; land use and management; leaf area index; soil mesofaunal diversity; soil C and N stocks, and greenhouse gas emissions from soils. These complement existing methods to provide a complete assessment of ecological integrity. These protocols offer integrated approaches to ecological data collection that are low cost and are starting to be used across the European Long Term Ecological Research community. [ABSTRACT FROM AUTHOR]

Question What are the direct and indirect effects of cattle grazing on temporal turnover in Mediterranean herbaceous communities, and are there differences between species (taxonomic) and functional turnover rates? Are turnover rates related to changes in precipitation patterns? Location The long term ecological research ( LTER) station, Ramat Hanadiv Nature Park, Israel. Methods We used data from a Mediterranean LTER site to analyse temporal turnover in herbaceous communities under cattle grazing and control conditions, while accounting for the potential effects of precipitation and woody cover. We analysed two types of temporal turnover: taxonomic turnover (changes in species composition) and turnover in functional traits (changes in the relative abundance of species with different functional traits). Results We found that communities exhibited rapid taxonomic turnover between sampling years, which was mostly explained by changes in precipitation patterns. Furthermore, there was a strong and consistent directional trend in taxonomic turnover (21% per decade) throughout the study period, which was correlated with a long-term trend of decreasing precipitation. This trend, however, was not significantly explained by grazing, woody cover change or their interaction. Grazing did have a significant effect on short-term turnover rates, but its effects varied in both direction and magnitude among sites located in different habitats. Temporal turnover in functional traits was much slower than taxonomic turnover, and was also inconsistent among traits and sites. Grazing reduced the bi-annual turnover rates in the composition of different life forms, and reduced the decadal turnover rate in the composition of different height groups in the community. Conclusions The results of this analysis suggest that the effect of cattle grazing on the temporal dynamics of herbaceous communities in Mediterranean ecosystems is habitat- and trait-specific, and unrelated to changes in woody cover. In contrast, inter-annual changes in precipitation patterns have a much stronger effect on turnover rates. The relationship between temporal species turnover and precipitation in these communities is therefore in line with modern co-existence theory, by which fluctuating environmental conditions facilitate long-term species co-existence. [ABSTRACT FROM AUTHOR]

The drivers and pressures experienced by farmland, forestry and upland sites in the UK Environmental Change Network (ECN) over the last 20 years are reported through the lens of recognised approaches to the assessment of ecosystem service delivery. Temporal trends in ecosystem service delivery were examined using two methods: qualitative narratives and quantitative scoring of ecosystem service delivery according to land cover. While all sites included in this study are within the same national governance unit (i.e. UK), individual local management decisions were the main agents driving change, influenced by EU and national policies. Gradual change in focus from provisioning to cultural ecosystem services was a persistent trend across most sites, and apparent in both methods. There was generally no net loss in regulating services at the sites. The two methods were subjective but as data were not available for the breadth of ecosystem services present at the sites between 1993 and 2012, it was concluded that it is more informative for holistic assessments to draw on qualitative expert opinion than to ignore less quantifiable services such as many of the cultural services. [ABSTRACT FROM AUTHOR]

Liming and fertilization of grasslands have been used for centuries to sustain hay production. Besides improving hay yields, these practices induce compositional shifts in plant and soil microbial communities, including symbiotic arbuscular mycorrhizal (AM) fungi. However, in spite of increasing interest in soil carbon (C) sequestration to offset anthropogenic CO 2 emissions, little is known about the long-term effects of these agronomic interventions on soil C stocks. We examined how plants, AM fungi, and soil C respond to more than seven decades of annual applications of lime, mineral nitrogen (N), and mineral phosphorus (P) to test the hypotheses that (1) management practices increasing aboveground plant production decrease C allocation to roots, AM fungi and the soil; and (2) the relative availability of N and P predicts belowground C allocation in a consistent manner. Our study was conducted at the Rengen Grassland Experiment, established in 1941. Lime combined with N increased hay yields and promoted development of AM fungal hyphae in soil, while reducing relative C allocation to roots. Simultaneous enrichment of soil with lime, N, and P further boosted hay production, promoted grasses and suppressed other plant functional groups. This treatment also decreased soil organic C and strongly suppressed AM fungi in the soil, although the response to P varied among different AM fungal taxa. Our results indicate that agricultural management practices aimed at maximization of hay production may, in the long run, significantly (−20%) reduce belowground C storage. This is a great concern with respect to the intended use of grasslands as anthropogenic CO 2 sinks because the fertilization-induced decrease in soil C stocks can partly or fully negate the C sequestration potential of the grassland ecosystems as a whole. [ABSTRACT FROM AUTHOR]

Background: Water resources are of fundamental importance to society, and are better managed by stakeholders who understand resource issues. Gaining such knowledge is a lifelong process best begun at an early age and best supported by educational approaches integrating across science, technology, engineering and mathematics (STEM). Research scientists can bring resource education to young audiences through children’s books and curricula that emphasise and integrate across STEM principals. Aims: To encourage empathy for the environment in younger students, researchers at the Niwot Ridge Long Term Ecological Research site have developed a children’s book series and methods for training teachers in water science education. Methods: Children’s books in theMy Waterseries are paired with curricula, hands-on learning kits, teacher development training and dissemination of materials through school districts to further water science education. Results: Thousands of children and educators have received training through theMy Waterbook series, and a more broadly focused, federally funded Schoolyard Children’s Book Series has grown out of these efforts towards water resource education. Conclusions: Children’s books and curricula that integrate STEM principals can play a key role in the development of environmental empathy and lifelong learning to support resource management. [ABSTRACT FROM PUBLISHER]

Italy entered the International Long Term Ecological Research Network (ILTER) in 2006, contributing a group of research sites in marine, freshwater and terrestrial ecosystems to the global network. Five forest sites are included in the Italian Network. They are representative of the main forest ecosystems in Italy and integrate 15 research stations managed by different institutes. Starting from LTER rationale and basic concepts, the first part of the paper reviews the status of LTER Italy forest sites, the strengths resulting from multidisciplinary expertise and site management, current activities and available datasets. Long term data series on key environmental parameters show the high scientific value of these sites, where monitoring and/or research is still ongoing. But two main LTER issues are currently arising in the international context: (1) overall consistency of datasets; (2) harmonization of sampling methods. For this reason, the second part of the paper investigates the suitability of Italian forest sites to address recommended long term research topics and ecological issues of global concern and to investigate the shift from in-site monitoring to crosssite cooperation and inter-site research. [ABSTRACT FROM AUTHOR]

Simple Summary: Rain seldom falls in the extremely arid Namib Desert in Namibia, but when a certain amount falls, it causes seeds to germinate, grass to grow and seed, dry, and turn to litter that gradually decomposes over the years. It is thought that such periodic flushes and gradual decay are fundamental to the functioning of the animal populations of deserts. This notion was tested with litter-consuming darkling beetles, of which many species occur in the Namib. Beetles were trapped in buckets buried at ground level, identified, counted, and released. The numbers of most species changed with the quantity of litter, but some mainly fed on green grass and disappeared when this dried, while other species depended on the availability of moisture during winter. Several species required unusually heavy rainfalls to gradually increase their populations, while others the opposite, declining when wet, thriving when dry. All 26 beetle species experienced periods when their numbers were extremely low, but all had the capacity for a few remaining individuals to repopulate the area in good times. The remarkably different relationships of these beetles to common resources, litter, and moisture, explain how so many species can exist side by side in such a dry environment. Noy-Meir's paradigm concerning desert populations being predictably tied to unpredictable productivity pulses was tested by examining abundance trends of 26 species of flightless detritivorous tenebrionid beetles (Coleoptera, Tenebrionidae) in the hyper-arid Namib Desert (MAP = 25 mm). Over 45 years, tenebrionids were continuously pitfall trapped on a gravel plain. Species were categorised according to how their populations increased after 22 effective rainfall events (>11 mm in a week), and declined with decreasing detritus reserves (97.7–0.2 g m−2), while sustained by nonrainfall moisture. Six patterns of population variation were recognised: (a) increases triggered by effective summer rainfalls, tracking detritus over time (five species, 41% abundance); (b) irrupting upon summer rainfalls, crashing a year later (three, 18%); (c) increasing gradually after series of heavy (>40 mm) rainfall years, declining over the next decade (eight, 15%); (d) triggered by winter rainfall, population fluctuating moderately (two, 20%); (e) increasing during dry years, declining during wet (one, 0.4%); (f) erratic range expansions following heavy rain (seven, 5%). All species experienced population bottlenecks during a decade of scant reserves, followed by the community cycling back to its earlier composition after 30 years. By responding selectively to alternative configurations of resources, Namib tenebrionids showed temporal patterns and magnitudes of population fluctuation more diverse than predicted by Noy-Meir's original model, underpinning high species diversity. [ABSTRACT FROM AUTHOR]

Percentile-Range Indexed Mapping and Evaluation (PRIME) is a new tool to visualize and quantifying spatio-temporal dynamics of long-term datasets. PRIME is based on categorical partitioning of magnitude based on user defined indices assigned to ranges of percentile and mapping subsets of data at selected percentiles of long-term data. Indices can reflect attributes such as water management decisions, tolerable range of water quality to a species, ecological risk, response to and recovery from disturbance, and values of ecosystem services. PRIME provides visual and robust datascapes and flexibility to evaluate variability in space and time for long-term environmental assessment. Here, we demonstrate the utility of PRIME using 16 years of hydrologic and salinity data from 14 sites representing three unique hydrological systems in the Florida Coastal Everglades (FCE). The resulting PRIME datascapes reveal interaction between water management and sea-level rise to drive salinity levels in the FCE. • Introduces PRIME, a new tool for synthesis and visualization of long-term data. • PRIME provides a novel mapping strategy by scaling time series data to percentiles. • PRIME allows for comparison among different types of datasets. • PRIME is intended for both non-specialist users and experts. [ABSTRACT FROM AUTHOR]

Large‐scale observational data from citizen science efforts are becoming increasingly common in ecology, and researchers often choose between these and data from intensive local‐scale studies for their analyses. This choice has potential trade‐offs related to spatial scale, observer variance, and interannual variability. Here we explored this issue with phenology by comparing models built using data from the large‐scale, citizen science USA National Phenology Network (USA‐NPN) effort with models built using data from more intensive studies at Long Term Ecological Research (LTER) sites. We built statistical and process based phenology models for species common to each data set. From these models, we compared parameter estimates, estimates of phenological events, and out‐of‐sample errors between models derived from both USA‐NPN and LTER data. We found that model parameter estimates for the same species were most similar between the two data sets when using simple models, but parameter estimates varied widely as model complexity increased. Despite this, estimates for the date of phenological events and out‐of‐sample errors were similar, regardless of the model chosen. Predictions for USA‐NPN data had the lowest error when using models built from the USA‐NPN data, while LTER predictions were best made using LTER‐derived models, confirming that models perform best when applied at the same scale they were built. This difference in the cross‐scale model comparison is likely due to variation in phenological requirements within species. Models using the USA‐NPN data set can integrate parameters over a large spatial scale while those using an LTER data set can only estimate parameters for a single location. Accordingly, the choice of data set depends on the research question. Inferences about species‐specific phenological requirements are best made with LTER data, and if USA‐NPN or similar data are all that is available, then analyses should be limited to simple models. Large‐scale predictive modeling is best done with the larger‐scale USA‐NPN data, which has high spatial representation and a large regional species pool. LTER data sets, on the other hand, have high site fidelity and thus characterize inter‐annual variability extremely well. Future research aimed at forecasting phenology events for particular species over larger scales should develop models that integrate the strengths of both data sets. [ABSTRACT FROM AUTHOR]