TY - JOUR
T1 - Soil biological responses to C, N and P fertilization in a polar desert of Antarctica
AU - Ball, Rebecca
AU - Adams, Byron J.
AU - Barrett, J. E.
AU - Wall, Diana H.
AU - Virginia, Ross A.
N1 - Funding Information:
We thank Anthony Faiia and Paul Zietz (Dartmouth) and Natalya Zolotova (Keck Lab, ASU) for assistance with sample processing and analysis. Additional lab support was provided by Tim Pattyson (ASU). This research was supported by National Science Foundation Office of Polar Program grants to the McMurdo Long-Term Ecological Research Program ANT-0423595 , OPP-1115245 , and funds from the New College of Interdisciplinary Arts & Sciences at Arizona State University .
Publisher Copyright:
© 2018 Elsevier Ltd
PY - 2018/7
Y1 - 2018/7
N2 - In the polar desert ecosystem of the McMurdo Dry Valleys of Antarctica, biology is constrained by available liquid water, low temperatures, as well as the availability of organic matter and nutrient elements. These soil ecosystems are climate-sensitive, where projected future warming may have profound effects on biological communities and biogeochemical cycling. Warmer temperatures will mobilize meltwater from permafrost and glaciers, may increase precipitation and may be accompanied by pulses of nutrient availability. Enhanced water and nutrient availability have the potential to greatly influence desert soil biology and ecosystem processes. The objectives of this 5-year study were to determine which nutrient elements (C, N, P) are most limiting to dry valley soil communities and whether landscape history (i.e., in situ soil type and stoichiometry) influences soil community response to nutrient additions. After 3 years of no noticeable response, soil CO2 flux was significantly higher under addition of C+ N than the other treatments, regardless of in situ soil stoichiometry, but microbial biomass and invertebrate abundance were variable and not influenced in the same manner. A stable isotope incubation suggests that fertilization increases C and N mineralization from organic matter via stimulating microbial activity, with loss of both the applied treatments as well in situ C and N. However, these responses are relatively short-lived, suggesting long-term impacts on C and N cycling would only occur if meltwater and nutrient pulses are sustained over time, a scenario that is increasingly likely for the dry valleys.
AB - In the polar desert ecosystem of the McMurdo Dry Valleys of Antarctica, biology is constrained by available liquid water, low temperatures, as well as the availability of organic matter and nutrient elements. These soil ecosystems are climate-sensitive, where projected future warming may have profound effects on biological communities and biogeochemical cycling. Warmer temperatures will mobilize meltwater from permafrost and glaciers, may increase precipitation and may be accompanied by pulses of nutrient availability. Enhanced water and nutrient availability have the potential to greatly influence desert soil biology and ecosystem processes. The objectives of this 5-year study were to determine which nutrient elements (C, N, P) are most limiting to dry valley soil communities and whether landscape history (i.e., in situ soil type and stoichiometry) influences soil community response to nutrient additions. After 3 years of no noticeable response, soil CO2 flux was significantly higher under addition of C+ N than the other treatments, regardless of in situ soil stoichiometry, but microbial biomass and invertebrate abundance were variable and not influenced in the same manner. A stable isotope incubation suggests that fertilization increases C and N mineralization from organic matter via stimulating microbial activity, with loss of both the applied treatments as well in situ C and N. However, these responses are relatively short-lived, suggesting long-term impacts on C and N cycling would only occur if meltwater and nutrient pulses are sustained over time, a scenario that is increasingly likely for the dry valleys.
KW - Nutrient fertilization
KW - Polar desert
KW - Soil invertebrates
KW - Soil respiration
KW - Stoichiometry
KW - Water pulses
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U2 - 10.1016/j.soilbio.2018.03.025
DO - 10.1016/j.soilbio.2018.03.025
M3 - Article
AN - SCOPUS:85044744500
SN - 0038-0717
VL - 122
SP - 7
EP - 18
JO - Soil Biology and Biochemistry
JF - Soil Biology and Biochemistry
ER -