Regional patterns of sulfur retention in watersheds of the Eastern US

Rochelle, Barry P.; Church, M. Robbins

doi:10.1007/bf00450620

Cited by 65 publications

(18 citation statements)

References 19 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…These changes can occur even in the absence of additional depositionai changes. For example, in the mid-Appalachian and southeastern portions of the United States, soils are continuing to retain sulfate by inorganic absorption onto oxide surfaces and will not achieve steady state for several decades (Rochelle and Church 1987). Therefore, one would not want to use observed relationships between depositional fluxes of sulfate and the concentrations of this species in surface waters to project future surface water sulfate concentrations.…”

Section: Empirical and Statistical Analysesmentioning

confidence: 98%

A national critical loads framework for atmospheric deposition effects assessment: IV. Model selection, applications, and critical loads mapping

Holdren¹,

Strickland²,

Cosby

et al. 1993

Environmental Management

View full text Add to dashboard Cite

ABSTRACT/The critical loads approach is emerging as an attractive means for evaluating the effects of atmospheric deposition on sensitive terrestrial and aquatic ecosystems. Various approaches are available for modeling ecosystem responses to deposition and for estimating critical load values. These approaches include empirical and statistical relationships, steady-state and simple process models, and integrated-effects models. For any given ecosystem, the most technically sophisticated approach will not necessarily be the most appropriate for all applications; identification of the most useful approach depends upon the degree of accuracy needed and upon data and computational requirements, biogeochemical processes being modeled, approaches used for representing model results on regional bases, and desired degree of spatial and temporal resolution. Different approaches are characterized by different levels of uncertainty. If the limitations of individual approaches are known, the user can determine whether an approach provides a reasonable basis for decision making. Several options, including point maps, grid maps, and ecoregional maps, are available for presenting model results in a regional context. These are discussed using hypothetical examples for choosing populations and damage limits.

show abstract

Section: Empirical and Statistical Analysesmentioning

confidence: 98%

A national critical loads framework for atmospheric deposition effects assessment: IV. Model selection, applications, and critical loads mapping

Holdren¹,

Strickland²,

Cosby

et al. 1993

Environmental Management

View full text Add to dashboard Cite

show abstract

“…Export of SO4-appears to be due to oxidation of the organic S contained in the forest vegetation and soil by fire and leaching of the released SO 4-via streamflow. Clearcutting (and herbicide application) would presumably release S contained in the dead debris but the appearance of SO4-in streams is mediated by soil absorption which varies widely in North America (Rochelle & Church 1987).…”

Section: Chemical Concentrations In Stream After Firementioning

confidence: 99%

Effects of forest fire and drought on acidity of a base-poor boreal forest stream: similarities between climatic warming and acidic precipitation

et al. 1992

View full text Add to dashboard Cite

Abstract. In a boreal forest catchment in the Experimental Lakes Area in northwestem Ontario, wildfire caused an increase in the concentrations of strong acid anions and base cations of the stream. In the naturally base-poor Northwest (NW) Subbasin, a 1980 wildfire caused exports of strong acid anions to increase more than export of base cations, causing a 2.5 fold increase in the acidity of the stream. Mean annual stream pH declined from 5.15 prior to fire to 4.76 two years after fire. Acid-neutralizing capacity (ANC), calculated as the difference between total base cations and strong acid anions, decreased to 20% of pre-fire values. Sulfate and chloride were the strong acid anions responsible for the decline in ANC, increasing four-fold. While nitrate increased eleven-fold, concentrations were too low to significantly affect ANC. There was a significant correlation between weekly sulfate concentration and base cation concentration (r 2 ~ 0.83) in the two years after fire. Recovery of ANC was caused by the more rapid decline in concentration of sulfate than by changes in base cations. Drought produced a similar but weaker response than fire, with increased sulfate concentrations and decreased stream pH. Climatic warming that increases drought and fire frequency would have effects that mimic the impacts of acidic precipitation (i.e. higher sulfate concentrations and acidic stream waters). Areas which have higher concentrations of stored S from past acid precipitation or have large areas of peatlands in the watershed may have aggravated losses of S and H + after drought and fire.

show abstract

“…As SO 4 -S inputs have decreased to WS4, we may be seeing release of S in recent years due to lower concentrations in deposition, as hypothesized by Rochelle and Church (1987) and Reuss and Johnson (1986). Sulfate adsorption can be induced by increasing SO 4 concentration and suggesting saturation of SO adsorption capacity, at least in the streamside zone.…”

Section: Internal Cyclingmentioning

confidence: 93%