Deposition and processing of airborne nitrogen pollutants in Mediterranean-type ecosystems of southern California

Riggan, Philip J.; Lockwood, Robert N.; Lopez, Ernest N.

doi:10.1021/es00139a003

Cited by 130 publications

(125 citation statements)

References 12 publications

Supporting

Mentioning

120

Contrasting

Order By: Relevance

“…However, forests that are stagnant, in decline, or have been disturbed (Swank 1988 (Riggan et al 1985). (Mitchell et al 1996a).…”

Section: Nitrate Leaching and Exportmentioning

confidence: 99%

“…Fire suppression has contributed to the development of N saturation in fire-adapted ecosystems in southern California by allowing N to accumulate in soil and the forest floor (Riggan et al 1985. Implementing prescribed fire in N-saturated, fire-adapted ecosystems will: (1) release N from the system, and (2) prepare a seedbed for regeneration of seedlings or induce resprouting of shrubs that will later be much stronger N sinks than decadent vegetation.…”

Section: Potential Management Practicesmentioning

confidence: 99%

See 1 more Smart Citation

Nitrogen Excess in North American Ecosystems: Predisposing Factors, Ecosystem Responses, and Management Strategies

Fenn¹,

Poth²,

Aber³

et al. 1998

Ecological Applications

328

492

View full text Add to dashboard Cite

Abstract. Most forests in North America remain nitrogen limited, although recent studies have identified forested areas that exhibit symptoms of N excess, analogous to overfertilization of arable land. Nitrogen excess in watersheds is detrimental because of disruptions in plant/soil nutrient relations, increased soil acidification and aluminum mobility, increased emissions of nitrogenous greenhouse gases from soil, reduced methane consumption in soil, decreased water quality, toxic effects on freshwater biota, and eutrophication of coastal marine waters. Elevated nitrate ( ) loss to groundwater Ϫ

show abstract

“…However, forests that are stagnant, in decline, or have been disturbed (Swank 1988 (Riggan et al 1985). (Mitchell et al 1996a).…”

Section: Nitrate Leaching and Exportmentioning

confidence: 99%

Section: Potential Management Practicesmentioning

confidence: 99%

Nitrogen Excess in North American Ecosystems: Predisposing Factors, Ecosystem Responses, and Management Strategies

Fenn¹,

Poth²,

Aber³

et al. 1998

Ecological Applications

328

492

View full text Add to dashboard Cite

show abstract

“…The effects of chronic nitrogen (N) deposition in areas of the western United States include increased greenhouse gas emissions (Fenn et al 1996(Fenn et al , 2003b, higher N concentrations in plant tissues (Fenn et al 2003a), and increased nitrification rates and nitrate (NO 3 À ) levels in soil, streams, and lakes (Riggan et al 1985;Williams et al 1996;Fenn and Poth 1999;Sickman et al 2002). N deposition has caused some environmental problems such as reduced drinking water quality and eutrophication of recipient water bodies, NO 3 À -induced changes in plant community composition, disruption, and contributions to regional haze and impaired visibility Fenn et al (2003a, b).…”

Section: Introductionmentioning

confidence: 99%

“…The long-term dynamics of water, carbon (C) and N in chaparral ecosystems under the effects of N deposition are not well known. Field studies of C and N biogeochemistry in chaparral ecosystems over the last three decades have included biomass and net primary production (NPP) (Mooney and Rundel 1979;Schlesinger and Gill 1980;Parsons and Stohlgren 1986), nutrient cycling (Christensen and Muller 1975;Rundel and Parsons 1980;Gary and Schlesinger 1983;Graham and Wood 1991;Ulery et al 1995;Fenn et al 1996), ecological effects of N deposition (Riggan et al 1985(Riggan et al , 1994Fenn et al 1996Fenn et al , 2003a, greenhouse gaseous N emissions (Anderson and Poth 1989;Fenn et al 1996), and stream NO 3 À export (Davis 1989;Fenn et al 2003c). Our understanding of ecological processes in chaparral ecosystems is derived from short-term studies of less than a few years at a limited set of intensively studied sites.…”

Section: Introductionmentioning

confidence: 99%

Decadal-scale Dynamics of Water, Carbon and Nitrogen in a California Chaparral Ecosystem: DAYCENT Modeling Results

Meixner

Sickman

et al. 2006

Biogeochemistry

View full text Add to dashboard Cite

Abstract. The Mediterranean climate, with its characteristic of dry summers and wet winters, influences the hydrologic and microbial processes that control carbon (C) and nitrogen (N) biogeochemical processes in chaparral ecosystems. These biogeochemical processes in turn determine N cycling under chronic N deposition. In order to examine connections between climate and N dynamics, we quantified decadal-scale water, C and N states and fluxes at annual, monthly and daily time steps for a California chaparral ecosystem in the Sierra Nevada using the DAYCENT model. The daily output simulations of net mineralization, stream flow and stream nitrate (NO 3 À ) export were developed for DAYCENT in order to simulate the N dynamics most appropriate for the abrupt rewetting events characteristic of Mediterranean chaparral ecosystems. Overall, the magnitude of annual modeled net N mineralization, soil and plant biomass C and N, nitrate export and gaseous N emission agreed with those of observations. Gaseous N emission was a major N loss pathway in chaparral ecosystems, in which nitric oxide (NO) is the dominant species. The modeled C and N fluxes of net primary production (NPP), N uptake and N mineralization, NO 3 À export and gaseous N emission showed both high inter-annual and intraannual variability. Our simulations also showed dramatic fire effects on NPP, N uptake, N mineralization and gaseous N emission for three years of postfire. The decease in simulated soil organic C and N storages was not dramatic, but lasted a longer time. For the seasonal pattern, the predicted C and N fluxes were greatest during December to March, and lowest in the summer. The model predictions suggested that an increase in the N deposition rate would increase N losses through gaseous N emission and stream N export in the chaparral ecosystems of the Sierra Nevada due to changes in N saturation status. The model predictions could not capture stream NO 3 À export during most rewetting events suggesting that a dry-rewetting mechanism representing the increase in N mineralization following soil wetting needs to be incorporated into biogeochemical models of semi-arid ecosystems.

show abstract

“…Chaparral ecosystem responses to N deposition include elevated NO 3 -leaching in streamwater and nitric oxide (NO) emissions from soil, increased direct transport Factors predisposing both California chaparral and forests to N loss are the active nitrifying characteristics of the soils , Fenn et al 1993, Riggan et al 1985, Vourlitis and Zorba 2007. Chaparral soils exposed to chronic N deposition exhibit elevated N cycling, as evidenced by lower carbon:nitrogen (C:N) ratios, higher N mineralization rates, and increased  15 N (Vourlitis and Zorba 2007).…”

Section: Ecosystem Responses To N Depositionmentioning

confidence: 99%

Assessment of Nitrogen deposition effects and empirical critical loads of Nitrogen for ecoregions of the United States

Pardo¹,

Robin-Abbott²,

Driscoll³

2011

View full text Add to dashboard Cite

Human activity in the last century has led to a substantial increase in nitrogen (N) emissions and deposition. This N deposition has reached a level that has caused or is likely to cause alterations to the structure and function of many ecosystems across the United States. One approach for quantifying the level of pollution that would be harmful to ecosystems is the critical loads approach. The critical load is defi ned as the level of a pollutant below which no detrimental ecological effect occurs over the long term according to present knowledge.The objective of this project was to synthesize current research relating atmospheric N deposition to effects on terrestrial and aquatic ecosystems in the United States and to identify empirical critical loads for atmospheric N deposition. The receptors that we evaluated included freshwater diatoms, mycorrhizal fungi and other soil microbes, lichens, herbaceous plants, shrubs, and trees. The main responses reported fell into two categories: (1) biogeochemical, and (2) individual species, population, and community responses.The range of critical loads for nutrient N reported for U.S. ecoregions, inland surface waters, and freshwater wetlands is 1 to 39 kg N ha -1 y -1. This broad range spans the range of N deposition observed over most of the country. The empirical critical loads for N tend to increase in the following sequence for different life forms: diatoms, lichens and bryophytes, mycorrhizal fungi, herbaceous plants and shrubs, trees.The critical loads approach is an ecosystem assessment tool with great potential to simplify complex scientifi c information and effectively communicate with the policy community and the public. This synthesis represents the fi rst comprehensive assessment of empirical critical loads of N for ecoregions across the United States.

show abstract

Deposition and processing of airborne nitrogen pollutants in Mediterranean-type ecosystems of southern California

Cited by 130 publications

References 12 publications

Nitrogen Excess in North American Ecosystems: Predisposing Factors, Ecosystem Responses, and Management Strategies

Nitrogen Excess in North American Ecosystems: Predisposing Factors, Ecosystem Responses, and Management Strategies

Decadal-scale Dynamics of Water, Carbon and Nitrogen in a California Chaparral Ecosystem: DAYCENT Modeling Results

Assessment of Nitrogen deposition effects and empirical critical loads of Nitrogen for ecoregions of the United States

Contact Info

Product

Resources

About