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S.W. Bailey

Publications and source records attributed to S.W. Bailey.

9 recordsLinked to original sources
USGS2020

Reversal of forest soil acidification in the northeastern United States and eastern Canada: Site and soil factors contributing to recovery

As acidic deposition has decreased across Eastern North America, forest soils at some sites are beginning to show reversal of soil acidification. However, the degree of recovery appears to vary and is not fully explained by deposition declines alone. To assess if other site and soil factors can help to explain degree of recovery from acid deposition, soil resampling chemistry data (8- to 24-year time interval) from 23 sites in the United States and Canada, located across 25° longitude from Eastern Maine to Western Ontario, were explored. Site and soil factors included recovery years, sulfate (SO 4 2− ) deposition history, SO 4 2− reduction rate, C horizon pH and exchangeable calcium (Ca), O and B horizon pH, base saturation, and exchangeable Ca and aluminum (Al) at the time of the initial sampling. We found that O and B horizons that were initially acidified to a greater degree showed greater recovery and B horizon recovery was further associated with an increase in recovery years and lower initial SO 4 2− deposition. Forest soils that seemingly have low buffering capacity and a reduced potential for recovery have the resilience to recover from the effects of previous high levels of acidic deposition. This suggests, that predictions of where forest soils acidification reversal will occur across the landscape should be refined to acknowledge the importance of upper soil profile horizon chemistry rather than the more traditional approach using only parent material characteristics.

Soil Systems↗
USGS2010

Identifying sources of stream water sulfate after a summer drought in the Sleepers River watershed (Vermont, USA) using hydrological, chemical, and isotopic techniques

In many forested headwater catchments, peak SO 4 2 - concentrations in stream water occur in the late summer or fall following drought potentially resulting in episodic stream acidification. The sources of highly elevated stream water SO 4 2 - concentrations were investigated in a first order stream at the Sleepers River watershed (Vermont, USA) after the particularly dry summer of 2001 using a combination of hydrological, chemical and isotopic approaches. Throughout the summer of 2001 SO 4 2 - concentrations in stream water doubled from ???130 to 270 ??eq/L while flows decreased. Simultaneously increasing Na + and Ca 2+ concentrations and ?? 34 S values increasing from +7??? towards those of bedrock S (???+10.5???) indicated that chemical weathering involving hydrolysis of silicates and oxidation of sulfide minerals in schists and phyllites was the cause for the initial increase in SO 4 2 - concentrations. During re-wetting of the watershed in late September and early October of 2001, increasing stream flows were accompanied by decreasing Na + and Ca 2+ concentrations, but SO 4 2 - concentrations continued to increase up to 568 ??eq/L, indicating that a major source of SO 4 2 - in addition to bedrock weathering contributed to peak SO 4 2 - concentrations. The further increase in SO 4 2 - concentrations coincided with an abrupt decrease of ?? 34 S values in stream water SO 4 2 - from maximum values near +10??? to minimum values near -3???. Soil investigations revealed that some C-horizons in the Spodsols of the watershed contained secondary sulfide minerals with ?? 34 S values near -22???. The shift to negative ?? 34 S values of stream water SO 4 2 - indicates that secondary sulfides in C-horizons were oxidized to SO 4 2 - during the particularly dry summer of 2001. The newly formed SO 4 2 - was transported to the streams during re-wetting of the watershed contributing ???60% of the SO 4 2 - during peak concentrations in the stream water. Thereafter, the contribution of SO 4 2 - from oxidation of secondary sulfides in C-horizons decreased rapidly and pedogenic SO 4 2 - reemerged as a dominant SO 4 2 - source in concert with decreasing SO 4 2 - concentrations in spring of 2002. The study provides evidence that a quantitative assessment of the sources of stream water SO 4 2 - in forested watersheds is possible by combining hydrological, chemical and isotopic techniques, provided that the isotopic compositions of all potential SO 4 2 - sources are distinctly different. ?? 2010 Elsevier Ltd.

Applied Geochemistry↗
USGS2008

Climatically driven loss of calcium in steppe soil as a sink for atmospheric carbon

During the last several thousand years the semi-arid, cold climate of the Russian steppe formed highly fertile soils rich in organic carbon and calcium (classified as Chernozems in the Russian system). Analysis of archived soil samples collected in Kemannaya Steppe Preserve in 1920, 1947, 1970, and fresh samples collected in 1998 indicated that the native steppe Chernozems, however, lost 17-28 kg m-2 of calcium in the form of carbonates in 1970-1998. Here we demonstrate that the loss of calcium was caused by fundamental shift in the steppe hydrologic balance. Previously unleached soils where precipitation was less than potential evapotranspiration are now being leached due to increased precipitation and, possibly, due to decreased actual evapotranspiration. Because this region receives low levels of acidic deposition, the dissolution of carbonates involves the consumption of atmospheric CO2. Our estimates indicate that this climatically driven terrestrial sink of atmospheric CO2 is ???2.1-7.4 g C m-2 a-1. In addition to the net sink of atmospheric carbon, leaching of pedogenic carbonates significantly amplified seasonal amplitude of CO2 exchange between atmosphere and steppe soil. Copyright 2008 by the American Geophysical Union.

Global Biogeochemical Cycles↗
USGS2008

Fine root dynamics and forest production across a calcium gradient in northern hardwood and conifer ecosystems

Losses of soil base cations due to acid rain have been implicated in declines of red spruce and sugar maple in the northeastern USA. We studied fine root and aboveground biomass and production in five northern hardwood and three conifer stands differing in soil Ca status at Sleepers River, VT; Hubbard Brook, NH; and Cone Pond, NH. Neither aboveground biomass and production nor belowground biomass were related to soil Ca or Ca:Al ratios across this gradient. Hardwood stands had 37% higher aboveground biomass (P = 0.03) and 44% higher leaf litter production (P < 0.01) than the conifer stands, on average. Fine root biomass (<2 mm in diameter) in the upper 35 cm of the soil, including the forest floor, was very similar in hardwoods and conifers (5.92 and 5.93 Mg ha-1). The turnover coefficient (TC) of fine roots smaller than 1 mm ranged from 0.62 to 1.86 y-1 and increased significantly with soil exchangeable Ca (P = 0.03). As a result, calculated fine root production was clearly higher in sites with higher soil Ca (P = 0.02). Fine root production (biomass times turnover) ranged from 1.2 to 3.7 Mg ha-1 y-1 for hardwood stands and from 0.9 to 2.3 Mg ha-1 y -1 for conifer stands. The relationship we observed between soil Ca availability and root production suggests that cation depletion might lead to reduced carbon allocation to roots in these ecosystems. ?? 2008 Springer Science+Business Media, LLC.

Ecosystems↗
USGS2006

One-day rate measurements for estimating net nitrification potential in humid forest soils

Measurements of net nitrification rates in forest soils have usually been performed by extended sample incubation (2-8 weeks), either in the field or in the lab. Because of disturbance effects, these measurements are only estimates of nitrification potential and shorter incubations may suffice. In three separate studies of northeastern USA forest soil surface horizons, we found that laboratory nitrification rates measured over 1 day related well to those measured over 4 weeks. Soil samples of Oa or A horizons were mixed by hand and the initial extraction of subsamples, using 2 mol L-1 KCl, occurred in the field as soon as feasible after sampling. Soils were kept near field temperature and subsampled again the following day in the laboratory. Rates measured by this method were about three times higher than the 4-week rates. Variability in measured rates was similar over either incubation period. Because NO3- concentrations were usually quite low in the field, average rates from 10 research watersheds could be estimated with only a single, 1-day extraction. Methodological studies showed that the concentration of NH4+ increased slowly during contact time with the KCl extractant and, thus, this contact time should be kept similar during the procedure. This method allows a large number of samples to be rapidly assessed. ?? 2006 Elsevier B.V. All rights reserved.

Forest Ecology and Management↗
USGS2005

Climate dependency of tree growth suppressed by acid deposition effects on soils in Northwest Russia

Increased tree growth in temperate and boreal forests has been proposed as a direct consequence of a warming climate. Acid deposition effects on nutrient availability may influence the climate dependency of tree growth, however. This study presents an analysis of archived soil samples that has enabled changes in soil chemistry to be tracked with patterns of tree growth through the 20th century. Soil samples collected in 1926, 1964, and 2001, near St. Petersburg, Russia, showed that acid deposition was likely to have decreased root-available concentrations of Ca (an essential element) and increased root-available concentrations of Al (an inhibitor of Ca uptake). These soil changes coincided with decreased diameter growth and a suppression of climate-tree growth relationships in Norway spruce. Expected increases in tree growth from climate warming may be limited by decreased soil fertility in regions of northern and eastern Europe, and eastern North America, where Ca availability has been reduced by acidic deposition. ?? 2005 American Chemical Society.

Environmental Science & Technology↗
USGS2005

Identifying calcium sources at an acid deposition-impacted spruce forest: A strontium isotope, alkaline earth element multi-tracer approach

Depletion of calcium from forest soils has important implications for forest productivity and health. Ca is available to fine feeder roots from a number of soil organic and mineral sources, but identifying the primary source or changes of sources in response to environmental change is problematic. We used strontium isotope and alkaline earth element concentration ratios of trees and soils to discern the record of Ca sources for red spruce at a base-poor, acid deposition-impacted watershed. We measured 87 Sr/ 86 Sr and chemical compositions of cross-sectional stemwood cores of red spruce, other spruce tissues and sequential extracts of co-located soil samples. 87 Sr/ 86 Sr and Sr/Ba ratios together provide a tracer of alkaline earth element sources that distinguishes the plant-available fraction of the shallow organic soils from those of deeper organic and mineral soils. Ca/Sr ratios proved less diagnostic, due to within-tree processes that fractionate these elements from each other. Over the growth period from 1870 to 1960, 87 Sr/ 86 Sr and Sr/Ba ratios of stemwood samples became progressively more variable and on average trended toward values that considered together are characteristic of the uppermost forest floor. In detail the stemwood chemistry revealed an episode of simultaneous enhanced uptake of all alkaline earth elements during the growth period from 1930 to 1960, coincident with reported local and regional increases in atmospheric inputs of inorganic acidity. We attribute the temporal trends in stemwood chemistry to progressive shallowing of the effective depth of alkaline earth element uptake by fine roots over this growth period, due to preferential concentration of fine roots in the upper forest floor coupled with reduced nutrient uptake by roots in the lower organic and upper mineral soils in response to acid-induced aluminum toxicity. Although both increased atmospheric deposition and selective weathering of Ca-rich minerals such as apatite provide possible alternative explanations of aspects of the observed trends, the chemical buffering capacity of the forest floor-biomass pool limits their effectiveness as causal mechanisms.

Biogeochemistry↗
USGS1997

Streamwater chemistry and nutrient budgets for forested watersheds in New England: Variability and management implications

Chemistry of precipitation and streamwater and resulting input-output budgets for nutrient ions were determined concurrently for three years on three upland, forested watersheds located within an 80 km radius in central New England. Chemistry of precipitation and inputs of nutrients via wet deposition were similar among the three watersheds and were generally typical of central New England. In contrast, chemistry and nutrient outputs in streamwater varied dramatically between watersheds, with chemistries ranging from acidic to alkaline. Comparisons with data reported for 159 other upland, forested watersheds in central New England show that our study watersheds span the regional range likely to be encountered in stream chemistry. The regional variability stems in part from past natural disturbances such as wildfire, and variations in source of soil parent material. An approach is presented for predicting the important influence of glacial till on stream chemistry, including acid-base relationships, aluminum content, and nutrient outputs. Knowledge of streamwater chemistry and controlling factors can serve as an index of how terrestrial and aquatic ecosystems will respond to forest management activities and atmospheric deposition.

Forest Ecology and Management↗