Size of precipitation pulses controls nitrogen transformation and losses in an arid Patagonian ecosystem

Laura Yahdjian, Osvaldo Sala

Research output: Contribution to journalArticle

53 Citations (Scopus)

Abstract

Arid ecosystems receive precipitation pulses of different sizes that may differentially affect nitrogen (N) losses and N turnover during the growing season. We designed a rainfall manipulation experiment in the Patagonian steppe, southern Argentina, where we simulated different precipitation patterns by adding the same amount of water in evenly spaced three-small rainfall events or in one-single large rainfall event, three times during a growing season. We measured the effect of the size of rainfall pulses on N mineralization and N losses by denitrification, ammonia volatilization, and nitrate and ammonia leaching. Irrigation pulses stimulated N mineralization (P < 0.05), with small and frequent pulses showing higher responses than large pulses (P < 0.10). Irrigation effects were transient and did not result in changes in seasonal net N mineralization suggesting a long-term substrate limitation. Water pulses stimulated gaseous N losses by denitrification, with large pulses showing higher responses than small pulses (P < 0.05), but did not stimulate ammonia volatilization. Nitrate leaching also was higher after large than after small precipitation events (P < 0.05). Small events produced higher N transformations and lower N losses by denitrification and nitrate leaching than large events, which would produce higher N availability for plant growth. Climate change is expected to increase the frequency of extreme precipitation events and the proportion of large to small rainfall events. Our results suggest that these changes would result in reduced N availability and a competitive advantage for deep-rooted species that prefer nitrate over ammonia. Similarly, the ammonium:nitrate ratio might decrease because large events foster nitrate losses but not ammonium losses.

Original languageEnglish (US)
Pages (from-to)575-585
Number of pages11
JournalEcosystems
Volume13
Issue number4
DOIs
StatePublished - 2010
Externally publishedYes

Fingerprint

Ecosystems
Nitrogen
Nitrates
Rain
nitrates
rain
Ammonia
ammonia
ecosystems
denitrification
ecosystem
Denitrification
nitrate
nitrogen
rainfall
leaching
mineralization
Leaching
volatilization
Vaporization

Keywords

  • Ammonia volatilization
  • Arid ecosystems
  • Denitrification
  • Net N mineralization
  • Nitrate leaching
  • Nitrogen-water interactions
  • Patagonian steppe
  • Precipitation pulses
  • Soil inorganic N

ASJC Scopus subject areas

  • Ecology, Evolution, Behavior and Systematics
  • Ecology
  • Environmental Chemistry

Cite this

Size of precipitation pulses controls nitrogen transformation and losses in an arid Patagonian ecosystem. / Yahdjian, Laura; Sala, Osvaldo.

In: Ecosystems, Vol. 13, No. 4, 2010, p. 575-585.

Research output: Contribution to journalArticle

@article{ab4e91161ddb4f6bb8cedc17e45f339b,
title = "Size of precipitation pulses controls nitrogen transformation and losses in an arid Patagonian ecosystem",
abstract = "Arid ecosystems receive precipitation pulses of different sizes that may differentially affect nitrogen (N) losses and N turnover during the growing season. We designed a rainfall manipulation experiment in the Patagonian steppe, southern Argentina, where we simulated different precipitation patterns by adding the same amount of water in evenly spaced three-small rainfall events or in one-single large rainfall event, three times during a growing season. We measured the effect of the size of rainfall pulses on N mineralization and N losses by denitrification, ammonia volatilization, and nitrate and ammonia leaching. Irrigation pulses stimulated N mineralization (P < 0.05), with small and frequent pulses showing higher responses than large pulses (P < 0.10). Irrigation effects were transient and did not result in changes in seasonal net N mineralization suggesting a long-term substrate limitation. Water pulses stimulated gaseous N losses by denitrification, with large pulses showing higher responses than small pulses (P < 0.05), but did not stimulate ammonia volatilization. Nitrate leaching also was higher after large than after small precipitation events (P < 0.05). Small events produced higher N transformations and lower N losses by denitrification and nitrate leaching than large events, which would produce higher N availability for plant growth. Climate change is expected to increase the frequency of extreme precipitation events and the proportion of large to small rainfall events. Our results suggest that these changes would result in reduced N availability and a competitive advantage for deep-rooted species that prefer nitrate over ammonia. Similarly, the ammonium:nitrate ratio might decrease because large events foster nitrate losses but not ammonium losses.",
keywords = "Ammonia volatilization, Arid ecosystems, Denitrification, Net N mineralization, Nitrate leaching, Nitrogen-water interactions, Patagonian steppe, Precipitation pulses, Soil inorganic N",
author = "Laura Yahdjian and Osvaldo Sala",
year = "2010",
doi = "10.1007/s10021-010-9341-6",
language = "English (US)",
volume = "13",
pages = "575--585",
journal = "Ecosystems",
issn = "1432-9840",
publisher = "Springer New York",
number = "4",

}

TY - JOUR

T1 - Size of precipitation pulses controls nitrogen transformation and losses in an arid Patagonian ecosystem

AU - Yahdjian, Laura

AU - Sala, Osvaldo

PY - 2010

Y1 - 2010

N2 - Arid ecosystems receive precipitation pulses of different sizes that may differentially affect nitrogen (N) losses and N turnover during the growing season. We designed a rainfall manipulation experiment in the Patagonian steppe, southern Argentina, where we simulated different precipitation patterns by adding the same amount of water in evenly spaced three-small rainfall events or in one-single large rainfall event, three times during a growing season. We measured the effect of the size of rainfall pulses on N mineralization and N losses by denitrification, ammonia volatilization, and nitrate and ammonia leaching. Irrigation pulses stimulated N mineralization (P < 0.05), with small and frequent pulses showing higher responses than large pulses (P < 0.10). Irrigation effects were transient and did not result in changes in seasonal net N mineralization suggesting a long-term substrate limitation. Water pulses stimulated gaseous N losses by denitrification, with large pulses showing higher responses than small pulses (P < 0.05), but did not stimulate ammonia volatilization. Nitrate leaching also was higher after large than after small precipitation events (P < 0.05). Small events produced higher N transformations and lower N losses by denitrification and nitrate leaching than large events, which would produce higher N availability for plant growth. Climate change is expected to increase the frequency of extreme precipitation events and the proportion of large to small rainfall events. Our results suggest that these changes would result in reduced N availability and a competitive advantage for deep-rooted species that prefer nitrate over ammonia. Similarly, the ammonium:nitrate ratio might decrease because large events foster nitrate losses but not ammonium losses.

AB - Arid ecosystems receive precipitation pulses of different sizes that may differentially affect nitrogen (N) losses and N turnover during the growing season. We designed a rainfall manipulation experiment in the Patagonian steppe, southern Argentina, where we simulated different precipitation patterns by adding the same amount of water in evenly spaced three-small rainfall events or in one-single large rainfall event, three times during a growing season. We measured the effect of the size of rainfall pulses on N mineralization and N losses by denitrification, ammonia volatilization, and nitrate and ammonia leaching. Irrigation pulses stimulated N mineralization (P < 0.05), with small and frequent pulses showing higher responses than large pulses (P < 0.10). Irrigation effects were transient and did not result in changes in seasonal net N mineralization suggesting a long-term substrate limitation. Water pulses stimulated gaseous N losses by denitrification, with large pulses showing higher responses than small pulses (P < 0.05), but did not stimulate ammonia volatilization. Nitrate leaching also was higher after large than after small precipitation events (P < 0.05). Small events produced higher N transformations and lower N losses by denitrification and nitrate leaching than large events, which would produce higher N availability for plant growth. Climate change is expected to increase the frequency of extreme precipitation events and the proportion of large to small rainfall events. Our results suggest that these changes would result in reduced N availability and a competitive advantage for deep-rooted species that prefer nitrate over ammonia. Similarly, the ammonium:nitrate ratio might decrease because large events foster nitrate losses but not ammonium losses.

KW - Ammonia volatilization

KW - Arid ecosystems

KW - Denitrification

KW - Net N mineralization

KW - Nitrate leaching

KW - Nitrogen-water interactions

KW - Patagonian steppe

KW - Precipitation pulses

KW - Soil inorganic N

UR - http://www.scopus.com/inward/record.url?scp=77953609641&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=77953609641&partnerID=8YFLogxK

U2 - 10.1007/s10021-010-9341-6

DO - 10.1007/s10021-010-9341-6

M3 - Article

AN - SCOPUS:77953609641

VL - 13

SP - 575

EP - 585

JO - Ecosystems

JF - Ecosystems

SN - 1432-9840

IS - 4

ER -