Find research datasets worth reusing
Search datasets from major research repositories and use ShareScore to quickly assess how well each record supports discovery, access, and reuse.
709
datasets available to search
ShareScore release 0.7.1
Dataset results
709 results for “soil carbon”
Soil carbon flux: Effect of Burning Patterns on Vegetation in the Fish Lake Burn Compartments
This study examines the effects of long-term prescribed burning treatments on vegetation structure and composition, productivity, and nutrient cycling in upland oak savanna and woodland vegetation. The basis for the study is an ongoing, experimental prescribed burning program begun in 1964 at Cedar Creek, and a similar program operating since 1962 on the adjacent Helen Allison Savanna property (owned by The Nature Conservancy). These prescribed burning programs are designed to subject upland oak communities (and some old fields) to different burn frequencies and patterns of burning, with the ultimate objectives of 1) restoring and maintaining the historically important savanna and open woodland vegetation, and 2) providing information about the effects of different burning patterns on vegetation structure and composition. This study addresses the latter of these two purposes and expands on it by also investigating possible influences of fire on resource availability (nutrients, water, and light) and net primary productivity. This study represents a continuation and expansion of experiments 015 and 094.
Soil carbon: Nitrogen Addition and Dynamics of Recovery from Cessation of N Addition
This experiment was established on top of E002 in fields A and C. In the spring of 1992, 3 randomly chosen replicates of each nutrient treatment of experiment E002 were chosen to receive no more fertilizer. For a description of these plots, see E002. For a description of fertilizer added to E097, see file fertilization details. For a list of treatments, see the treatment layouts in file trmte97.
Soil carbon: Fire X Nitrogen: Interactive Effects in a Prairie-Like Grassland
This experiment was established on top of E002 in field B. In the spring of 1992, 3 randomly chosen replicates of each nutrient treatment of experiment E002 were chosen to be burned each spring. For a description of these plots, see E002. For a list of treatments, see the treatment layouts in file trmte98.
Soil carbon: Long-Term Nitrogen Deposition: Population, Community, and Ecosystem Consequences
The purpose of this experiment is to measure how adding nitrogen over a long time will affect the number of species, the type of species present, the amount of annual growth, and the change from year to year in the growth of each species in a plant community which is also relieved of grazing by large and small mammals. The experiment is being conducted within fields (A, B, C, and D) which were initially low in soil nutrients. There are 8 different levels of nitrogen addition with other nutrients added to ensure that nitrogen remains the limiting nutrient, and a control which receives no nutrients. There are 6 replicates of the 9 treatments in fields A, B, and C and 5 replicates in field D. The treatments were randomly assigned to the plots. In fields A, B, and C the plots are in 6 by 9 grids and are 4 by 4 meters in size with 1 meter aisles between plots. In field D the plots are 1.5 by 4 meters and are placed in a 3 by 17 grid. The plots are enclosed by a fence to keep out mammalian herbivores. Gophers are trapped and removed as they appear. Nitrogenfertilizer (NH4NO3) is applied twice per year, once in early May and once in late June. This experiment was begun in 1982 by David Tilman.
Soil carbon: Herbivory by Nitrogen Interactive Effects on Community and Ecosystem Processes and Dynamics
E172 is an herbivory experiment established by Dave Tilman in fall 2004 by enclosing in deer fences three randomly selected plots from the six replicates of each control and each treatment in the N addition E001 experiment in field C. These plots still receive the nutrient treatments prescribed in the Experiment 001 protocols. From 1982-2004 a fence containing all of e001 plots in Field C was designed to exclude deer and all small mammals, including mice, voles and pocket gophers. This fence was removed in Fall of 2004 and individual plots designated for e172 were enclosed in deer fences. The purpose of E001 was to measure how adding nitrogen over a long time would affect the number of species, the type of species present, the amount of annual growth, and the change from year to year in the growth of each species in a plant community which is also relieved of grazing by large and small mammals. There are 8 different levels of nitrogen addition with other nutrients added to ensure that nitrogen remains the limiting nutrient, and a control which receives no nutrients. The plots are in a 6 by 9 grid and are 4 by 4 meters in size with 1 meter aisles between plots. Nitrogen fertilizer (NH4NO3) is applied twice per year, once in early May and once in late June.
Total and non-hydrolyzable soil carbon and nitrogen:BioCON : Biodiversity, Elevated CO2, and N Enrichment
BioCON (Biodiversity, CO2, and Nitrogen) is an ecological experiment started in 1997 at the University of Minnesota's Cedar Creek Ecosystem Science Reserve. BioCON's goal is to explore the ways in which plant communities will respond to three environmental changes that are known to be occurring on a global scale: increasing nitrogen deposition, increasing atmospheric CO2, and decreasing biodiversity. Why Biodiversity, CO2, and Nitrogen? While there are many uncertainties in global change biology, there are also some well documented facts. Some of these are: 1. The amount of carbon dioxide (CO2) in the atmosphere is rising. Since the industrial revolution, the CO2 concentration in the atmosphere has increased from approximately 275 parts per million (ppm) to about 378 ppm today. This has been largely the result of fossil fuel burning. It is expected that CO2 levels will continue to rise, and that by the year 2050 these levels will be approximately 550 ppm. CO2 is the raw material for photosynthesis and is known to affect plant growth and development. 2. The amount of nitrogen moving through terrestrial ecosystems has increased in the recent past. While natural "background" levels of nitrogen fixation have remained constant, human additions to the system through fertilizer production and fossil fuel use have increased dramatically. Nitrogen is a key nutrient for plant growth and plays a critical role in plant community structure and composition in many environments. 3. Biodiversity levels are falling. While the research and data are not as complete as they are for CO2 and nitrogen, data indicate that the number of species globally, is being reduced. Perhaps more important for ecosystem function, diversity levels on local to regional scales have fallen due to land use change, biotic invasion and many other drivers. While much is known about how each of these factors affects ecosystem functioning, many questions remain. There is also little data on how these issues affe
Soil carbon and nitrogen:Biodiversity: A field test of biofuel production and ground-water quality
Bioenergy could be an important part of the solution to the projected climate problems of the future, and in addition could provide auxiliary ecological services. The project described here aims to parameterize expected benefits of diverse prairie biofuel plantations for groundwater quality, and also to further evaluate its biofuel potential. This project, done in cooperation with the USGS, grows out of purely scientific discoveries in other Cedar Creek experiments. We know that diverse prairie systems are better able to retain inorganic nitrogen than monoculture systems (e.g., Dijkstra etal. 2007). However, nitrogen is just one pollutant of many being delivered to surface-water and ground-water from agricultural systems. There are a number of others including phosphorus, pesticides, and veterinary pharmaceuticals. This fact combined with the rising demand for corn grain ethanol could lead to further declines in the water quality of agricultural regions in the United States. Perennial vegetative buffers, in particular diverse prairies and/or hay (CRP), are proposed solutions. The vegetation in such buffers can be used for biofuel and simultaneously appear to be attenuate leaching of agricultural compounds through the unsaturated zone to groundwater. This 3-year cooperative USGS and UMN study will (1) examine the ability of prairies and hay (CRP) to attenuate leaching of agricultural compounds to ground-water (2) compare biofuel production of four cropping systems: diverse prairie, hay (CRP), corn grown with chemical fertilizer, and corn grown with a combination of manure and chemical fertilizer, (3) provide for future investigations into microbial antibiotic resistance and (4) provide a better understanding of the unsaturated zone hydrology and shallow groundwater recharge at Cedar Creek. The project will take place in the E120 field.
Soil carbon flux:Effects of Long Term Fertilization and Oak Canopy Cover on Plant Communities and Ecosystem Processes
In 1996 E142 was established in field D on top of the E004 macroplots. E004 was conducted in fields A, B, C and D by Dave Tilman. The purpose of E004 was to see what effect NH4NO3 addition has on large areas over a longer period of time with exposure to naturally-occurring levels of herbivory. The nutrient addition treatments in E004, E142 plots have been applied annually since 1982. These experiments, along with others at Cedar Creek, examine the community and ecosystem consequences of chronic nutrient loading.
TeRaCON eight years data - species composition, productivity (NPP), soil carbon emissions and plant carbon stocks:BioCON: Biodiversity, CO2, and Nitrogen
BioCON (Biodiversity, CO2, and Nitrogen) is an ecological experiment started in 1997 at the University of Minnesota's Cedar Creek Ecosystem Science Reserve. BioCON's goal is to explore the ways in which plant communities will respond to three environmental changes that are known to be occurring on a global scale: increasing nitrogen deposition, increasing atmospheric CO2, and decreasing biodiversity. Why Biodiversity, CO2, and Nitrogen? While there are many uncertainties in global change biology, there are also some well documented facts. Some of these are: 1. The amount of carbon dioxide (CO2) in the atmosphere is rising. Since the industrial revolution, the CO2 concentration in the atmosphere has increased from approximately 275 parts per million (ppm) to about 378 ppm today. This has been largely the result of fossil fuel burning. It is expected that CO2 levels will continue to rise, and that by the year 2050 these levels will be approximately 550 ppm. CO2 is the raw material for photosynthesis and is known to affect plant growth and development. 2. The amount of nitrogen moving through terrestrial ecosystems has increased in the recent past. While natural "background" levels of nitrogen fixation have remained constant, human additions to the system through fertilizer production and fossil fuel use have increased dramatically. Nitrogen is a key nutrient for plant growth and plays a critical role in plant community structure and composition in many environments. 3. Biodiversity levels are falling. While the research and data are not as complete as they are for CO2 and nitrogen, data indicate that the number of species globally, is being reduced. Perhaps more important for ecosystem function, diversity levels on local to regional scales have fallen due to land use change, biotic invasion and many other drivers. While much is known about how each of these factors affects ecosystem functioning, many questions remain. There is also little data on how these issues affe
TeRaCON eight year mean of NPP, carbon pools, and soil flux:BioCON : Biodiversity, Elevated CO2, and N Enrichment
BioCON (Biodiversity, CO2, and Nitrogen) is an ecological experiment started in 1997 at the University of Minnesota's Cedar Creek Ecosystem Science Reserve. BioCON's goal is to explore the ways in which plant communities will respond to three environmental changes that are known to be occurring on a global scale: increasing nitrogen deposition, increasing atmospheric CO2, and decreasing biodiversity. Why Biodiversity, CO2, and Nitrogen? While there are many uncertainties in global change biology, there are also some well documented facts. Some of these are: 1. The amount of carbon dioxide (CO2) in the atmosphere is rising. Since the industrial revolution, the CO2 concentration in the atmosphere has increased from approximately 275 parts per million (ppm) to about 378 ppm today. This has been largely the result of fossil fuel burning. It is expected that CO2 levels will continue to rise, and that by the year 2050 these levels will be approximately 550 ppm. CO2 is the raw material for photosynthesis and is known to affect plant growth and development. 2. The amount of nitrogen moving through terrestrial ecosystems has increased in the recent past. While natural "background" levels of nitrogen fixation have remained constant, human additions to the system through fertilizer production and fossil fuel use have increased dramatically. Nitrogen is a key nutrient for plant growth and plays a critical role in plant community structure and composition in many environments. 3. Biodiversity levels are falling. While the research and data are not as complete as they are for CO2 and nitrogen, data indicate that the number of species globally, is being reduced. Perhaps more important for ecosystem function, diversity levels on local to regional scales have fallen due to land use change, biotic invasion and many other drivers. While much is known about how each of these factors affects ecosystem functioning, many questions remain. There is also little data on how these issues affe
Assessing the use of bison for savanna restoration at Cedar Creek Ecosystem Science Reserve: Soil Carbon and Nitrogen
Oak savanna is the most threatened ecosystem in Minnesota and fire, alone, is not restoring and preserving it. Our savanna restoration research started more than a half century ago in what had once been native savanna at Cedar Creek. It has shown that burning about 4 to 7 times per decade eliminates shrubs and non-savanna tree species and restores prairie grassland species. However, our 50 years of research is also showing that these frequent and intense fires are preventing oaks from regenerating. Bison are now known to be a keystone species for restoring and preserving grasslands, but their roles in savanna ecosystems remain unknown. In grasslands, bison preferentially graze the dominant warm season grasses that would otherwise outcompete wildflowers, thereby promoting plant coexistence and enhancing plant diversity. Here we propose to test whether bison grazing might promote the growth and survivorship of oak seedlings in burned savannas by reducing grass fuel for fires and by knocking back dominant grass competitors. We will maintain the existing fire frequencies and the design of the long-term burning experiment, while adding bison grazing as an additional factor in part of several burn units on the southeast side of the property. Bison will graze during the summer and early fall seasons. Grazing exclosures will be established, and oak seedlings will be planted, to test effects of bison grazing on early oak growth and survivorship. The outcomes we plan to achieve are to: (1) discover better restoration and preservation practices for savanna ecosystems; (2) determine how these practices impact savanna biodiversity; and (3) educate Minnesotans about the ecological heritage of their state, including the roles that bison, fire and biodiversity play in the functioning of savannas and other Minnesota ecosystems. We will achieve these goals and outcomes by: (1) restoring bison grazing to 200 acres of oak savanna; (2) experimentally testing whether bison grazing promot
Vegetation cover and Soil Organic Carbon along gradients of cattle grazing intensity in the Jornada Basin, July-August 2016
The goal of this Master’s thesis project, which was carried out in July and August of 2016, was to assess the effect of inferred grazing intensity on 1) vegetation cover type and 2) soil organic carbon (SOC) at the Jornada Experimental Range in southern New Mexico. A sampling transect was established at each of 3 long term cattle water sources (85-106 years old), beginning 5m from the water source and continuing 1500m outward. Soil bulk density, soil organic carbon, soil organic nitrogen, and dominant plant cover type (shrub, grass, and bare soil) were sampled at 20 locations on each transect. Two hypotheses evaluated in this study are: 1) higher grazing pressure near the water source will lead to reduced vegetation cover and C inputs into the soil, leading to higher SOC stocks in soil with far proximity to the water source; and 2) Grazing very close to the water source will exert high disturbance and deposit SOC via defecation, leading to higher SOC stocks in soil with close proximity to the water source.
SGS-LTER Ecosystem Stress Area - Soil Carbon & Nitrogen in shortgrass steppe on the Central Plains Experimental Range in Nunn, Colorado, USA 1991, ARS Study Number 3
This data package was produced by researchers working on the Shortgrass Steppe Long Term Ecological Research (SGS-LTER) Project, administered at Colorado State University. Long-term datasets and background information (proposals, reports, photographs, etc.) on the SGS-LTER project are contained in a comprehensive project collection within the Digital Collections of Colorado (http://digitool.library.colostate.edu/R/?func=collections&collection_id=3429). The data table and associated metadata document, which is generated in Ecological Metadata Language, may be available through other repositories serving the ecological research community and represent components of the larger SGS-LTER project collection. Water, nitrogen, and water-plus-nitrogen at levels beyond the range normally experience by shortgrass steppe communities were applied from 1971 through 1975, plant densities were sampled through 1977, and then sampling resumed in 1982, with sampling frequencies changing from annually to every other year. The initial sampling from 1970 to 1974 showed that the water and water plus nitrogen treatments had the strongest effect on plant community structure, both treatments increased biomass, and exotic weed species were noted on the water plus nitrogen treatment. Later sampling from 1982 to 1991 showed a ten-fold increase in exotic weed species on the water plus nitrogen plots as compared to the controls (Milchunas and Lauenroth 1995), a community change that has persisted on this site due to a chronic elevation of soil nitrogen caused by a plant tissue/soil organic matter feedback mechanism (Vinton and Burke 1995). In 1998, Six new treatments were superimposed on the historic study site. The six new treatments were: control, sugar, lignin, sawdust, lignin and sugar, and sawdust and sugar.In 2010, plots will be sampled every 5 years. Our objective in this study is to examine how plant communities change through time and explore implications of these changes for monitoring
SGS-LTER Ecosystem Stress Area - Soil Carbon & Nitrogen in shortgrass steppe on the Central Plains Experimental Range in Nunn, Colorado, USA 1991, ARS Study Number 3
This data package was produced by researchers working on the Shortgrass Steppe Long Term Ecological Research (SGS-LTER) Project, administered at Colorado State University. Long-term datasets and background information (proposals, reports, photographs, etc.) on the SGS-LTER project are contained in a comprehensive project collection within the Digital Collections of Colorado (http://digitool.library.colostate.edu/R/?func=collections&collection_id=3429). The data table and associated metadata document, which is generated in Ecological Metadata Language, may be available through other repositories serving the ecological research community and represent components of the larger SGS-LTER project collection. Water, nitrogen, and water-plus-nitrogen at levels beyond the range normally experience by shortgrass steppe communities were applied from 1971 through 1975, plant densities were sampled through 1977, and then sampling resumed in 1982, with sampling frequencies changing from annually to every other year. The initial sampling from 1970 to 1974 showed that the water and water plus nitrogen treatments had the strongest effect on plant community structure, both treatments increased biomass, and exotic weed species were noted on the water plus nitrogen treatment. Later sampling from 1982 to 1991 showed a ten-fold increase in exotic weed species on the water plus nitrogen plots as compared to the controls (Milchunas and Lauenroth 1995), a community change that has persisted on this site due to a chronic elevation of soil nitrogen caused by a plant tissue/soil organic matter feedback mechanism (Vinton and Burke 1995). In 1998, Six new treatments were superimposed on the historic study site. The six new treatments were: control, sugar, lignin, sawdust, lignin and sugar, and sawdust and sugar.In 2010, plots will be sampled every 5 years. Our objective in this study is to examine how plant communities change through time and explore implications of these changes for monitoring
SGS-LTER Ecosystem Stress Area - Soil Carbon & Nitrogen in shortgrass steppe on the Central Plains Experimental Range in Nunn, Colorado, USA 1991, ARS Study Number 3
This data package was produced by researchers working on the Shortgrass Steppe Long Term Ecological Research (SGS-LTER) Project, administered at Colorado State University. Long-term datasets and background information (proposals, reports, photographs, etc.) on the SGS-LTER project are contained in a comprehensive project collection within the Digital Collections of Colorado (http://digitool.library.colostate.edu/R/?func=collections&collection_id=3429). The data table and associated metadata document, which is generated in Ecological Metadata Language, may be available through other repositories serving the ecological research community and represent components of the larger SGS-LTER project collection. Water, nitrogen, and water-plus-nitrogen at levels beyond the range normally experience by shortgrass steppe communities were applied from 1971 through 1975, plant densities were sampled through 1977, and then sampling resumed in 1982, with sampling frequencies changing from annually to every other year. The initial sampling from 1970 to 1974 showed that the water and water plus nitrogen treatments had the strongest effect on plant community structure, both treatments increased biomass, and exotic weed species were noted on the water plus nitrogen treatment. Later sampling from 1982 to 1991 showed a ten-fold increase in exotic weed species on the water plus nitrogen plots as compared to the controls (Milchunas and Lauenroth 1995), a community change that has persisted on this site due to a chronic elevation of soil nitrogen caused by a plant tissue/soil organic matter feedback mechanism (Vinton and Burke 1995). In 1998, Six new treatments were superimposed on the historic study site. The six new treatments were: control, sugar, lignin, sawdust, lignin and sugar, and sawdust and sugar.In 2010, plots will be sampled every 5 years. Our objective in this study is to examine how plant communities change through time and explore implications of these changes for monitoring
Data from: Differential impacts of nitrogen addition on rhizosphere and bulk-soil carbon sequestration in an alpine shrubland
<p><span><span>1. Due to complex root-soil interactions, the responses of carbon (C) dynamics in the rhizosphere to elevated nitrogen (N) deposition may be different from those in bulk soil. However, the potentially different response of C dynamics in the rhizosphere and bulk soils and their contributions to soil C sequestration under N deposition is still not elucidated.</span></span></p> <p><span><span>2. We conducted an N addition experiment in an alpine shrubland dominated by <i>Sibiraea angustata</i> located on the eastern Qinghai-Tibet Plateau (QTP). We measured the soil organic C (SOC) contents and density fractions in the rhizosphere and bulk soils in the top 15 cm of mineral soil and then employed a numerical model based on the rhizosphere extent to evaluate how the rhizosphere modulates soil C sequestration under N addition. We also measured the microbial gene abundance and C-acquisition enzyme activities to assess microbial community responses to N addition.</span></span></p> <p><span><span>3. The results showed that nitrogen addition had opposite effects on the rhizosphere and bulk-soil C stocks. Specifically, N addition decreased the rhizosphere SOC content through increasing bacterial abundance, β-glucosidase activity, and thus accelerating the loss of free light fraction C (FLF-C). However, N addition increased the bulk-soil C content, which was corresponding with the reduced oxidase activities and the accelerated accumulation of heavy fraction C (HF-C) under N addition. Numerical model analysis showed that the decrease induced by N addition in rhizosphere SOC stock ranged from 0.11 to 3.01 kg C m<sup>-2</sup> as root exudation diffusion distance extended from 0.5 mm to 2 mm, while the corresponding increase in the bulk-soil C stock ranged from 1.91 to 4.08 kg C m<sup>-2</sup>. By synthesizing the dynamics of the SOC stocks in these two soil compartments under N addition, the SOC stock at the ecosystem level exhibited an increase in range of 0.73-2.44 kg C m<sup>-2</sup>.</span></span></p> <p><span><span>4. <i>Synthesis</i> Our results suggest that alpine shrublands on the eastern QTP have great potential for soil C sequestration under N deposition, and the magnitude of the sequestration would depend closely on the responses of rhizosphere microbial C processes and the rhizosphere extent. Our results highlight the importance of integrating rhizosphere processes into land surface models to accurately predict ecosystem functions in the background of elevated N deposition.</span></span></p>
Data from: Dynamics of deep soil carbon - insights from 14C time series across a climatic gradient
Quantitative constraints on soil organic matter (SOM) dynamics are essential for comprehensive understanding of the terrestrial carbon cycle. Deep soil carbon is of particular interest, as it represents large stocks and its turnover times remain highly uncertain. In this study, SOM dynamics in both the top and deep soil across a climatic (average temperature ~1-9 °C) gradient are determined using time-series (~20 years) 14C data from bulk soil and water-extractable organic carbon (WEOC). Analytical measurements reveal enrichment of bomb-derived radiocarbon in the deep soil layers on the bulk level during the last two decades. The WEOC pool is strongly enriched in bomb-derived carbon, indicating that it is a dynamic pool. Turnover time estimates of both the bulk and WEOC pool show that the latter cycles up to a magnitude faster than the former. The presence of bomb-derived carbon in the deep soil, as well as the rapidly turning WEOC pool across the climatic gradient implies that there likely is a dynamic component of carbon in the deep soil. Precipitation and bedrock type appear to exert a stronger influence on soil C turnover time and stocks as compared to temperature.
Effect of soil carbon amendments in reversing the legacy effect of plant invasion
<p>1. Invasive plant species are key drivers of global environmental changes leading to the disruption of ecosystems they invade. Many invasive species engage in novel niche construction through plant-soil feedbacks facilitated by the input of secondary compounds, which help their further spread and survival. These compounds can persist in soil even after the removal of the invader thus creating a legacy effect that inhibits the return of native flora and fauna. Thus, formulating active intervention strategies that can reverse niche construction is critical for the restoration of these invaded ecosystems.</p> <p>2. We hypothesized that the management practices that can reverse the soil carbon and nutrient cycling in invaded ecosystems can facilitate the rapid restoration of the invaded sites. We predicted that adding soil C amendments such as activated carbon and biochar can alter the microbial functional activity and nutrient cycling leading to the restoration of invaded habitats. We tested this hypothesis in an old-field in Massachusetts that has been invaded by Japanese knotweed (Polygonum cuspidatum) for >20 years.</p> <p>3. After two years of treatment application, the activated carbon and biochar amended plots had 80% more biomass of the prairie species than the control plots. The C amendments also altered soil nutrient cycling and fungal biomass and enzyme activity compared to the control plots. The nitrate content of C amended plots was 5 times higher than the non-amended control plots indicating an increased nitrogen mineralization in C amended plots potentially due to the sorption of phenolic compounds by activated carbon and biochar that makes them unavailable. This was further supported by the increased phenol oxidase activity which might have been less inhibited by tannins and led to increased organic matter decomposition.</p> <p>4. Synthesis and conclusions: Our results thus reveal the potential of soil C amendments in reversing niche construction and legacy effects of polyphenol-rich invasive species and indicate that biochar could be a more economically feasible alternative to activated carbon in restoring invaded ecosystems. Our results also emphasize that understanding the mechanism through which invasive species engage in niche construction is vital in formulating suitable knowledge-based restoration practices for invaded ecosystems.</p>
Soil organic carbon accumulation modes between pioneer and old-growth forest ecosystems
<p>1. Increasing evidence suggests that high biomass and litterfall do not necessarily bring about soil organic carbon (SOC) sinks, contrary to the assumption that higher litterfall implies higher SOC when designing carbon models. The underlying mechanism is related to the quality of litter. 2. We conducted 15 years (2000–2015) of consecutive field measurements of δ13C values in SOC and plants in a pioneer forest (Pinus massoniana forest, PF) and an old-growth forest (monsoon evergreen broadleaved forest, BF), using an isotope mixing model based on mass balance to quantify the effects of vegetation on SOC stock and soil characteristics. 3. The carbon to nitrogen (C/N) ratio of litter in BF was lower than that in PF. The proportion of organic carbon yield input to the soil (Cinput) to the total litter carbon loss during decomposition was 38.7 ± 3.3% and 28.0 ± 2.1% in BF and PF, respectively. New carbon input was higher in BF (148.7 ± 8.8 g C m−2 yr−1) than PF (99.7 ± 4.5 g C m−2 yr−1), though there was a non-significant difference in annual litterfall between the two forests. Moreover, the Cinput was concentrated in the topsoil layer in PF but distributed in a more dispersed state across the whole soil profile in BF. Consequently, only the δ13C values of SOC decreased in the topsoil layer of PF, whereas these decreased at both soil depths in BF from 2000 to 2015. 4. Compared with PF, BF exhibited higher carbon input and a more favourable soil environment for carbon storage. It was the amount of intermediate product (i.e., Cinput) of litter decomposition, not the amount of litterfall itself, that drove the contrasting differences in SOC status. 5. Synthesis and applications. Litter quality controls SOC accumulation by regulating the fate of decomposing litter, which may explain why old-growth forests can sustainably accumulate carbon in soil. This finding questions the carbon models that predict the dependence of SOC accumulation on biomass and litter yield and suggests that litter quality should be valued in future carbon cycling models.30-Jul-2020</p>
Data from: Montane meadows: A soil carbon sink or source?
<p>As the largest biogeochemically active terrestrial reserve of carbon (C), soils have the potential to either mitigate or amplify rates of climate change. Ecosystems with large C stocks and high rates of soil C sequestration, in particular, may have outsized impacts on regional and global C cycles. Montane meadows have large soil C stocks relative to surrounding ecosystems. However, anthropogenic disturbances in many meadows may have altered the balance of C inputs and outputs, potentially converting these soils from net C sinks to net sources of C to the atmosphere. Here, we quantified ecosystem-level C inputs and outputs to estimate the annual net soil C flux from 13 montane meadows spanning a range of conditions throughout the California Sierra Nevada. Our results suggest that meadow soils can be either large net C sinks (577.6 ± 250.5 g C m−2 y−1) or sources of C to the atmosphere (− 391.6 ± 154.2 g C m−2 y−1). Variation in the direction and magnitude of net soil C flux appears to be driven by belowground C inputs. Vegetation species and functional group composition were not associated with the direction of net C flux, but climate and watershed characteristics were. Our results demonstrate that, per unit area, montane meadows hold a greater potential for C sequestration than the surrounding forest. However, legacies of disturbance have converted some meadows to strong net C sources. Accurate quantification of ecosystem-level C fluxes is critical for the development of regional C budgets and achieving global emissions goals.</p>
ScienceDex guides
Understand access before you commit
These curated guides explain access requirements, typical timelines, costs, and reuse considerations for widely used research datasets.
Allen Brain Atlas
Allen Brain Atlas is an Allen Institute collection of brain map atlases, datasets, APIs, and analysis tools covering mouse, human, and non-human primate brain resources.
Annotated Behaviour and Observability Dataset (ABODe)
ABODe is a University of Edinburgh DataShare dataset for behavior classification in group-housed mice using home-cage video, identities, bounding boxes, ground-plate positions, and annotator labels.
DANDI Archive for NWB datasets
DANDI is a BRAIN Initiative archive for publishing and sharing neurophysiology data, including electrophysiology, optophysiology, and behavioral data packaged as NWB and related standards.
International Brain Laboratory public data
The International Brain Laboratory public data releases expose standardized mouse decision-making experiments, including Neuropixels recordings, widefield calcium imaging, behavior, and session metadata accessed through the ONE API.
OpenNeuro
OpenNeuro is a free, open platform for sharing neuroimaging datasets, with public search, dataset pages, and download paths for web, S3, DataLad, and the OpenNeuro CLI.