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Flow regulation has reduced the exchange of water, energy, and materials between rivers and floodplains, caused declines in native plant populations, and advanced the spread of nonnative plants. Naturalized flow regimes are regarded as a means to restore degraded riparian areas. We examined the effects of flood regime (short [SIFI] vs. long [LIFI] inter-flood interval) on plant community and soil inorganic nitrogen (N) dynamics in riparian forests dominated by native Populus deltoides var. wislizenii Eckenwalder (Rio Grande cottonwood) and nonnative Tamarix chinensis Lour. (salt cedar) along the regulated middle Rio Grande of New Mexico. The frequency of inundation (every 2–3 years) at SIFI sites better reflected...
In forests, total belowground carbon (C) flux (TBCF) is a large component of the C budget and represents a critical pathway for delivery of plant C to soil. Reducing uncertainty around regional estimates of forest C cycling may be aided by incorporating knowledge of controls over soil respiration and TBCF. Photosynthesis, and presumably TBCF, declines with advancing tree size and age, and photosynthesis increases yet C partitioning to TBCF decreases in response to high soil fertility. We hypothesized that these causal relationships would result in predictable patterns of TBCF, and partitioning of C to TBCF, with natural variability in leaf area index (LAI), soil nitrogen (N), and tree height in subalpine forests...
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This dataset contains measurements of chemical concentrations of soil samples representing 28 headwater drainage basins completely within the Adirondack Park of New York State (ADK Park), one basin partially in the ADK Park, and one watershed 2 kilometers from the ADK Park boundary. Seven of these watersheds have been sampled 2 or 3 times over periods of 12 to 22 years. Soil samples were collected from pit faces exposed by shoveling. Total mass of organic matter, carbon and nitrogen in the forest floor are also presented for 16 headwater drainage basins in the ADK Park. Forest floor mass data were determined from samples collected with soil corers. The presented data are organized by six projects: the Adirondack...
Categories: Data, Data Release - Revised; Types: ArcGIS REST Map Service, ArcGIS Service Definition, Downloadable, Map Service; Tags: Adirondack Park, Adirondack Park, New York, Ambient Monitoring, B horizon, B horizon, All tags...
Ecologists increasingly use plot-scale data to inform research and policy related to regional and global environmental change. For soil chemistry research, scaling from the plot to the region is especially difficult due to high spatial variability at all scales. We used a hierarchical Bayesian model of plot-scale soil nutrient pools to predict storage of soil organic carbon (oC), inorganic carbon (iC), total nitrogen (N), and available phosphorus (avP) in a 7962-km2 area including the Phoenix, Arizona, USA, metropolitan area and its desert and agricultural surroundings. The Bayesian approach was compared to a traditional approach that multiplied mean values for urban mesic residential, urban xeric residential, nonresidential...
We investigated the influence of long-term (56 years) grazing on organic and inorganic carbon (C) and nitrogen (N) contents of the plant-soil system (to 90 cm depth) in shortgrass steppe of northeastern Colorado. Grazing treatments included continuous season-long (May-October) grazing by yearling heifers at heavy (60-75% utilization) and light (20-35% utilization) stocking rates, and nongrazed exclosures. The heavy stocking rate resulted in a plant community that was dominated (75% of biomass production) by the C4 grass blue grama (Bouteloua gracilis), whereas excluding livestock grazing increased the production of C3 grasses and prickly pear cactus (Opuntia polycantha). Soil organic C (SOC) and organic N were not...
1 Phenolics are an important, biologically reactive component of the carbon (C) pool that moves from plants to soil. Once in soil, phenolics can regulate plant?soil feedbacks because of their influence on soil nitrogen biogeochemistry. 2 Roots are a largely overlooked potential source of below-ground phenolic C. We examined phenolic fluxes from plants to soil in an alpine ecosystem, where phenolics are associated with slow rates of nutrient cycling. Using a phenolic-rich forb (Acomastylis rossii) and a grass with low tissue phenolics (Deschampsia caespitosa), we asked whether leaves, leaf litter or roots are the dominant source of soil phenolics during the growing season. We also determined whether the composition...
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This data release includes metadata and tabular data that document estimates of litterfall, koa moth (Scotorythra paludicola) caterpillar frass production, soil nutrients, and foliar nutrients during 2013-2014 at Hakalau Forest National Wildlife Refuge. During this time, there was a massive defoliation event of Acacia koa (koa) trees by the koa moth. We monitored these metrics in 4 sites that varied in forest structure and composition at Hakalau. We used litter traps to monitor koa litter fall over time and foliar %N to estimate N inputs from litter. We used caterpillar counts, koa canopy estimates, frass production rates, and frass %N to estimate N inputs from frass on the landscape. We used resin bags under koa...
This data release includes metadata and tabular data that document estimates of litterfall, koa moth (Scotorythra paludicola) caterpillar frass production, soil nutrients, and foliar nutrients during 2013-2014 at Hakalau Forest National Wildlife Refuge. During this time, there was a massive defoliation event of Acacia koa (koa) trees by the koa moth. We monitored these metrics in 4 sites that varied in forest structure and composition at Hakalau. We used litter traps to monitor koa litter fall over time and foliar %N to estimate N inputs from litter. We used caterpillar counts, koa canopy estimates, frass production rates, and frass %N to estimate N inputs from frass on the landscape. We used resin bags under koa...
This data release includes metadata and tabular data that document estimates of litterfall, koa moth (Scotorythra paludicola) caterpillar frass production, soil nutrients, and foliar nutrients during 2013-2014 at Hakalau Forest National Wildlife Refuge. During this time, there was a massive defoliation event of Acacia koa (koa) trees by the koa moth. We monitored these metrics in 4 sites that varied in forest structure and composition at Hakalau. We used resin bags under koa canopy where frass was directly falling as compared to open grass sites where no frass was falling to monitor soil inorganic nitrogen and phosphorus over time. By comparing soil with frass inputs to frass inputs over time we could watch for...
The ability to exploit short-duration nutrient pulses may be an important factor in the competitive balance of plants and in shaping plant community structure. We investigated the growth responses and biomass production of six Great Basin plant species growing in monocultures in the field following a single pulse of nitrogen applied in early, mid, or late spring. As a control, we applied the same total quantity of N that was in each of the individual pulses as a continuous series of applications at twice-weekly intervals over 10 wk in the spring. Surprisingly, most of the species grown under the control, continuous N supply had lower growth rates, fewer tillers, and less biomass production than plants receiving...
Recent trends of increasing woody vegetation in arid and semiarid ecosystems may contribute substantially to the North American C sink. There is considerable uncertainty, however, in the extent to which woody encroachment alters dryland soil organic carbon (SOC) and total nitrogen (TN) pools. To date, studies assessing SOC and TN response to woody plant proliferation have not explicitly assessed the variability caused by shrub age or size and subcanopy spatial gradients. These factors were quantified via spatially intensive soil sampling around Prosopis velutina shrubs in a semidesert grassland, using shrub size as a proxy for age. We found that bulk density increased with distance from the bole (P < 0.005) and...
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We examined the 10-day response of soil microbial biomass-N to additions of carbon (dextrose) and nitrogen (NH4NO3) to water-amended soils in a factorial experiment in four plant communities of the Chihuahuan desert of New Mexico (U.S.A.). In each site, microbial biomass-N and soil carbohydrates increased and extractable soil N decreased in response to watering alone. Fertilization with N increased microbial biomass-N in grassland soils; whereas, fertilization with C increased microbial biomass-N and decreased extractable N and P in all communities dominated by shrubs, which have invaded large areas of grassland in the Chihuahuan desert during the last 100 years. Our results support the hypothesis that the control...
The nonnative annual grass Bromus tectorum has successfully replaced native vegetation in many arid and semiarid ecosystems. Initial introductions accompanied grazing and agriculture, making it difficult to separate the effects of invasion from physical disturbance. This study examined N dynamics in two recently invaded, undisturbed vegetation associations (C₃ and C₄). The response of these communities was compared to an invaded/disturbed grassland. The invaded/disturbed communities had higher surface NH₄� input in spring, whereas there were no differences for surface input of NO₃�. Soil inorganic N was dominated by NH₄�, but invaded sites had greater subsurface soil NO₃�. Invaded sites had greater...
Some single-factor experiments suggest that elevated CO2 concentrations can increase soil carbon, but few experiments have examined the effects of interacting environmental factors on soil carbon dynamics. We undertook studies of soil carbon and nitrogen in a multi-factor (CO2 × temperature × soil moisture) climate change experiment on a constructed old-field ecosystem. After four growing seasons, elevated CO2 had no measurable effect on carbon and nitrogen concentrations in whole soil, particulate organic matter (POM), and mineral-associated organic matter (MOM). Analysis of stable carbon isotopes, under elevated CO2, indicated between 14 and 19% new soil carbon under two different watering treatments with as...
Elaeagnus angustifolia L., a nonnative N2-fixer, has established within riparian corridors of the interior western United States and is now the fourth most frequently occurring woody riparian plant in this region. We examined whether E. angustifolia alters pools and fluxes of soil inorganic N at eight sites dominated by Populus deltoides ssp. wislizeni along the Rio Grande in New Mexico over 2 years. E. angustifolia contributed a small fraction of total leaf fall (<5% across sites) but accounted for a disproportionately high amount of N (19%) that entered the system from P. deltoides and E. angustifolia leaf fall, due to the high N content (>2%) of E. angustifolia senesced leaves. Soil inorganic N concentrations...
This data release includes metadata and tabular data that document estimates of litterfall, koa moth (Scotorythra paludicola) caterpillar frass production, soil nutrients, and foliar nutrients during 2013-2014 at Hakalau Forest National Wildlife Refuge. During this time, there was a massive defoliation event of Acacia koa (koa) trees by the koa moth. We monitored these metrics in 4 sites that varied in forest structure and composition at Hakalau. We used litter traps to monitor koa litter fall over time and foliar %N to estimate N inputs from litter. We used caterpillar counts, koa canopy estimates, frass production rates, and frass %N to estimate N inputs from frass on the landscape. We used resin bags under koa...
This data release includes metadata and tabular data that document estimates of litterfall, koa moth (Scotorythra paludicola) caterpillar frass production, soil nutrients, and foliar nutrients during 2013-2014 at Hakalau Forest National Wildlife Refuge. During this time, there was a massive defoliation event of Acacia koa (koa) trees by the koa moth. We monitored these metrics in 4 sites that varied in forest structure and composition at Hakalau. We used litter traps to monitor koa litter fall over time and foliar %N to estimate N inputs from litter. We used caterpillar counts, koa canopy estimates, frass production rates, and frass %N to estimate N inputs from frass on the landscape. We used resin bags under koa...
    map background search result map search result map Factors Determining Soil Microbial Biomass and Nutrient Immobilization in Desert Soils Adirondack New York soil chemistry data, 1992-2017 (ver. 1.1, December 2020) Hakalau litter, frass, soil, and understory foliar nitrogen during a koa moth outbreak, 2013-2014 Hakalau estimated frass production during a koa moth outbreak, 2013 Hakalau litterfall during a koa moth outbreak, 2013-2015 Hakalau soil nitrogen and phosphorus during a koa moth outbreak, 2013-2014 Hakalau understory foliar carbon and nitrogen during a koa moth outbreak, 2013-2014 Hakalau litter, frass, soil, and understory foliar nitrogen during a koa moth outbreak, 2013-2014 Hakalau estimated frass production during a koa moth outbreak, 2013 Hakalau litterfall during a koa moth outbreak, 2013-2015 Hakalau soil nitrogen and phosphorus during a koa moth outbreak, 2013-2014 Hakalau understory foliar carbon and nitrogen during a koa moth outbreak, 2013-2014 Factors Determining Soil Microbial Biomass and Nutrient Immobilization in Desert Soils Adirondack New York soil chemistry data, 1992-2017 (ver. 1.1, December 2020)