Neue wissenschaftliche Aufsätze
Ecosystems
| Latest Results for Ecosystems | ||
| The latest content available from Springer | ||
| Fire History and Long-Term Carbon Accumulation in Hemi-boreal Peatlands | ||
| 31. Mai 2023 | ||
| Abstract Fire can play an important role in peatlands by modifying plant communities and carbon (C) stocks. However, baseline disturbance data on peatland fire history are lacking in the hemi-boreal region. We sampled 29 peatlands in northern Michigan, Wisconsin, and Minnesota and used peat core records, radiocarbon dating, and infrared spectrometry to identify and date past fire events in 4 major hemi-boreal peatland ecotypes including open poor fens, treed poor fens, forested poor fens, and forested rich fens. In this region all types of poor fens had widely variable... | ||
| Seasonal Rainfall, Shrub Cover and Soil Properties Drive Production of Winter Annuals in the Northern Sonoran Desert | ||
| 30. Mai 2023 | ||
| Abstract Winter annual plants play an important role in arid and semiarid ecosystems because of their rapid response to resource pulses, which drive primary production that provides resources for herbivores and pollinators. Understanding the factors that control annual plant growth is key to predicting how arid and semiarid ecosystems will respond to changes in climate and resource availability from anthropogenic activities. We used a long-term nutrient enrichment experiment that spanned precipitation and urbanization gradients in central Arizona, USA, to examine the... | ||
| Tree Species Effects on Soil CO2 and CH4 Fluxes in a Mixed Temperate Forest | ||
| 30. Mai 2023 | ||
| Abstract Temperate forest soils are net sources of carbon dioxide (CO2) and net sinks for methane (CH4), the two greenhouse gases most responsible for contemporary global climate change. Both soil carbon fluxes are sensitive to their local tree communities due to the direct effects of tree traits as well as indirect effects of associated soil properties. We asked how tree species identity and diversity predicts the flux of CO2 and CH4 from soils, how the two net fluxes are related, and what tree and soil characteristics predict their magnitudes. In a mixed temperate forest... | ||
| Spatial and Temporal Patterns of Nitrogen Mobilization in Residential Lawns | ||
| 25. Mai 2023 | ||
| Abstract Identifying locations prone to exporting nitrogen (N), also called export control points, within residential landscapes, is key to determining N mitigation strategies. Within residential landscapes, lawns have the potential to act as either a sink of N via uptake and denitrification, or a source of N via additions such as fertilizer. Lawns draining to impervious surfaces are more likely to be sources of N loading to receiving water bodies through directly connected curb and sewer flow paths. We utilized small-scale rainfall experiments to examine whether... | ||
| Variable Tissue Stoichiometry Influences Nutrient Recycling by Invasive Freshwater Mussels in Nutrient-Poor Lakes | ||
| 23. Mai 2023 | ||
| Abstract Animal excretion provides nutrients for primary productivity and can be a crucial component of ecosystem nutrient cycling. The concentrations of carbon (C), nitrogen (N), and phosphorus (P) in an animal’s excretion are strongly influenced by the C:N:P stoichiometry (molar ratios) of its body and of the food it eats. We measured the C:N:P ratios of quagga mussel (Dreissena rostriformis bugensis) tissues and excreta and of seston across wide environmental and spatial gradients in the upper Laurentian Great Lakes. We then investigated how mussel excretion rates... | ||
| Assessing Energetic Pathways and Time Lags in Estuarine Food Webs | ||
| 11. Mai 2023 | ||
| Abstract Detecting strong species interactions in food webs is often challenging due to difficulties related to adequate experimentation and the prevalence of generalist diets throughout nature. A promising new mathematical technique, empirical dynamic modeling (EDM), has demonstrated the potential to identify trophic interactions between populations by assessing time lags between associated time series. We attempted to analyze trophic linkages both within a subtropical estuary, as well as a simulated, theoretical ecosystem, to determine how energy moves through these... | ||
| Decreased Soil Microbial Nitrogen Under Vegetation ‘Shrubification’ in the Subarctic Forest–Tundra Ecotone: The Potential Role of Increasing Nutrient Competition Between Plants and Soil... | ||
| 10. Mai 2023 | ||
| Abstract The consequences of warming-induced ‘shrubification’ on Arctic soil carbon storage are receiving increased attention, as the majority of ecosystem carbon in these systems is stored in soils. Soil carbon cycles in these ecosystems are usually tightly coupled with nitrogen availability. Soil microbial responses to ‘shrubification’ may depend on the traits of the shrub species that increase in response to warming. Increase in deciduous shrubs such as Betula nana likely promotes a loss of soil carbon, whereas the opposite may be true if evergreen shrubs such... | ||
| Deterioration of the Littoral–Benthic Ecosystem Following Recent Expansion of Signal Crayfish (Pacifastacus leniusculus) in the World’s Clearest Large Lake | ||
| 03. Mai 2023 | ||
| Abstract Some biological invasions can result in algae blooms in the nearshore of clear lakes. We studied if an invasive crayfish (Pacifastacus leniusculus) modified the biomass and community composition of benthic macroinvertebrates and therefore led to a trophic cascade resulting in increased periphyton biomass, elevated littoral primary productivity, and benthic algae bloom in a lake with remarkable transparency [Crater Lake, Oregon, USA]. After quantifying the changes in the spatial distribution of invasive crayfish over a 13-year period, we compared biomass and... | ||
| Carbon Stocks and Total Belowground Carbon Flux Respond to Weather and Grazing in Semiarid Montane Meadows | ||
| 24. April 2023 | ||
| Abstract Montane meadow ecosystems are regional carbon (C) hot spots relative to surrounding uplands and can be substantial C sinks or sources. In the semiarid Great Basin region of the western United States, meadows are vital to hydrology, livestock production, and wildlife. To elucidate factors contributing to meadow C cycling in the Great Basin, we measured the impact of interannual weather, grazing, vegetation communities, and edaphic characteristics on carbon stocks and total belowground C flux (TBCF) in meadows. Meadow carbon stocks were three times larger than... | ||
| Different Cerrado Ecotypes Show Contrasting Soil Microbial Properties, Functioning Rates, and Sensitivity to Changing Water Regimes | ||
| 24. April 2023 | ||
| Abstract Soil moisture is among the most important factors regulating soil biodiversity and functioning. Models forecast changes in the precipitation regime in many areas of the planet, but how these changes will influence soil functioning, and how biotic drivers modulate such effects, is far from being understood. We evaluated the responses of C and N fluxes, and soil microbial properties to different soil water regimes in soils from the main three ecotypes of the world's largest and most diverse tropical savanna. Further, we explored the direct and indirect effects of... | ||
| The Relative Importance of Coarse-Scale Climate and Fine-Scale Nitrogen Availability Contrasts in Driving Home-Field Advantage Effects in Litter Decomposition | ||
| 20. April 2023 | ||
| Abstract Understanding the relative importance of climates at coarse scales and nitrogen (N) availability at fine scales in driving litter decomposition is crucial for ecosystem functioning. In this study, we explored the relative importance of coarse-scale climatic contrast (China vs. France) and local soil fertility contrast related to N availability in determining ‘home-field advantage (HFA)’ effects. Four tree-species litters from four forest types with contrasting chemical properties from China and France were reciprocally transplanted in a litterbag... | ||
| Species Diversity and Stability of Dominant Species Dominate the Stability of Community Biomass in an Alpine Meadow Under Variable Precipitation | ||
| 14. April 2023 | ||
| Abstract The stability of aboveground net primary productivity (ANPP) is critical for ecosystem functions and services, and have been studied across a wide range of ecosystems. An intriguing and challenging question emerging from these studies is how precipitation fluctuations, especially extreme precipitation, affect the temporal stability of ANPP in alpine meadow. We investigated the changes in plant community composition and aboveground biomass in an alpine meadow over six consecutive years under five precipitation treatments (increase of 50%, natural precipitation... | ||
| Mycorrhiza Better Predict Soil Fungal Community Composition and Function than Aboveground Traits in Temperate Forest Ecosystems | ||
| 12. April 2023 | ||
| Abstract Forests in the northeastern US are experiencing shifts in community composition due to the northward migration of warm-adapted tree species and certain species’ declines (for example, white ash and eastern hemlock) due to invasive insects. Changes in belowground fungal communities and associated functions will inevitably follow. Therefore, we sought to investigate the relative importance of two important tree characteristics—mycorrhizal type [ectomycorrhizal (EcM) or arbuscular mycorrhizal (AM)] and leaf habit (deciduous or evergreen) on soil fungal community... | ||
| Simulating Soil Atmosphere Exchanges and CO2 Fluxes for an Ongoing Peat Extraction Site | ||
| 10. April 2023 | ||
| Abstract When extracting peat for horticultural use, drainage ditches are prepared, a peatland’s vegetation is removed, and peat is harvested. These land-use changes dramatically alter the carbon, water, and energy exchanges of the peatland and convert it from a moderate sink to a large source of CO2. We adapted the CoupModel to simulate the soil CO2 emission and its associated abiotic drivers for an ongoing horticultural peat extraction site, located in Riviére-du-loup (RdL), Quebec Canada. The model outputs were first evaluated against three years (2019–2021) of... | ||
| Experimental Evidence that Forest Structure Controls Detrital Decomposition | ||
| 10. April 2023 | ||
| Abstract Much remains unknown regarding the linkages between forest structure and microclimate as they regulate detrital decomposition. In this study, we use a factorial field experiment that included canopy gap creation and downed woody material (DW) additions conducted in a mature northern hardwood forest. Our objectives were to (1) test the individual and combined effects of canopy gaps and DW additions on detrital mass loss; (2) determine whether the factors regulating mass loss are similar among leaf litter, experimental wood stakes, and coarse DW; and (3) assess the... | ||
| Soil-Litter Mixing Mediates Drivers of Dryland Decomposition along a Continuum of Biotic and Abiotic Factors | ||
| 07. April 2023 | ||
| Abstract Litter decomposition is a key ecosystem process that determines rates of carbon and nutrient cycling. Photodegradation and soil-litter mixing have emerged as important drivers of dryland litter decomposition, but how these processes interact with decomposing microorganisms has received less attention. In this study, we examined the effects of ultraviolet-B radiation (UV-B; 280–315 nm) and soil-litter mixing on the decomposition of litter and its associated microbial community in an arid shrubland. We performed a full factorial litter decomposition experiment... | ||
| Toward a Standardized Method for Quantifying Ecosystem Hot Spots and Hot Moments | ||
| 04. April 2023 | ||
| Abstract Ecosystem “hot spots” and “hot moments”—respectively, places and times of disproportionately high biogeochemical activity—are an important and often invoked concept in ecosystem science. Despite the popularity of the concept, there is no standard approach to quantifying hot spots and hot moments, hindering progress in understanding the phenomenon. For example, lack of a standard quantitative approach hinders advances arising from synthesis across datasets and studies potentially representing different processes, ecosystem types, places, and times. We... | ||
| Integrating Beaver Ponds into the Carbon Emission Budget of Boreal Aquatic Networks: A Case Study at the Watershed Scale | ||
| 03. April 2023 | ||
| Abstract The ongoing recovery of beaver populations across the boreal biome of North America entails an increasing proliferation of beaver ponds in aquatic networks. Ecosystem-scale studies have demonstrated that beaver ponds are hotspots of carbon dioxide (CO2) and methane (CH4) production. However, beaver pond carbon (C) emissions have rarely been incorporated into estimates of inland water C budgets. Therefore, this potentially represents a major source of uncertainty for the C budget of the boreal biome. In this study, we combined a detailed geospatial analysis with... | ||
| Embracing Uncertainty and Probabilistic Outcomes for Ecological Critical Loads | ||
| 01. April 2023 | ||
| Abstract Species are a sensitive gauge of air quality only if the “signal” of their response to atmospheric deposition is properly distinguished from the “noise” of model error, measurement error and ecological variation. Here, we quantified and mapped uncertainty in ten lichen-based critical loads (CLs) or exceedances for nitrogen and sulfur deposition in the USA. We tested the effects of model error by Monte Carlo resampling of model parameters, and the effects of measurement error in the number and identity of species using bootstrap resampling. Measurement... | ||
| Pyric Herbivory and the Nexus Between Forage, Fire and Native and Introduced Large Grazing Herbivores in Australian Tropical Savannas | ||
| 01. April 2023 | ||
| Abstract Earth’s tropical savannas typically support high biomass of diverse grazing herbivores that depend on a highly fluctuating resource: high-quality forage. An annual wet–dry cycle, fire and herbivory combine to influence forage quality and availability throughout the year. In the savannas of northern Australia, a depauperate suite of large native (marsupial) herbivores (wallaroos [Osphranter spp.] and the agile wallaby [Notamacropus agilis]) compete for resources with non-native large herbivores introduced in the late nineteenth century, particularly bovines... | ||
