Direct and indirect effects of shifting rainfall on soil microbial respiration and enzyme activity in a semi-arid system
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Background and aims
Higher interannual precipitation variability is predicted for Southern California’s shrub-dominated systems, promoting soil moisture variation and changing community composition. We asked if soil microbial responses to rainfall regime will depend on litter inputs; showing direct effects of altered precipitation through soil moisture and indirect effects resulting from shifting litter inputs.
Soils were collected from a 2-year field rainfall manipulation experiment. Under lab conditions soils were subjected to high or low moisture pulses with litter amendments from native and exotic species in all combinations.
Soil respiration was higher with larger water pulses, but rose over time in low pulse treatments (direct response). Litter additions from exotic species promoted greater respiration, and results were stronger under higher soil moisture (indirect response). Extracellular enzyme activities generally were higher with exotic litter and under high moisture pulses. Those involved in N-cycling had much larger increases activity for the exotic litter addition - high moisture pulse scenarios compared to other treatments.
Our results indicate the potential for microbial acclimation to drought conditions over short timescales and that below-ground processes are sensitive to direct and indirect effects of shifting rainfall regimes, especially where invasion is promoted by future climate change.
KeywordsChaparral Exotic species Extracellular enzyme activity Microbial acclimation Microbial biomass Microbial respiration
Extracellular enzyme activity
We thank Rachel Abbott, Angie Ashbacher, and Christopher Kopp for maintaining the field experiment along with Rochelle Aran and Magali Porrachia for their laboratory assistance. This work was performed at the University of California Natural Reserve System and supported by a Mildred E. Mathias Graduate Student Research Grant from the University of California Natural Reserve System. This material is based upon work supported by the National Science Foundation Graduate Research Fellowship under Grant No. (DGE-1144086) and also a National Science Foundation Division of Environmental Biology grant (DEB 1154082). Any opinions, findings, and conclusions or recommendations expressed in this material are those of the authors and do not necessarily reflect the views of the National Science Foundation.
- American Public Health Association (1994) Water Environment Federation (1998) Standard methods for the examination of water and wastewater. Washington, DC, USAGoogle Scholar
- Ashbacher AC, Cleland EE (2015) Native and exotic plant species show differential growth but similar functional trait responses to experimental rainfall. Ecosphere 6. doi: 10.1890/Es15-00059.1
- Brando PM, Nepstad DC, Davidson EA, Trumbore SE, Ray D, Camargo P (2008) Drought effects on litterfall, wood production and belowground carbon cycling in an Amazon forest: results of a throughfall reduction experiment. Philos T R Soc B 363:1839–1848. doi: 10.1098/Rstb.2007.0031 CrossRefGoogle Scholar
- Cayan D et al. (2009) Climate change scenarios and sea level rise estimates for the California 2008 climate change scenarios assessment California Climate Change Center CEC-500-2009-014-D doi:http://www.energy.ca.gov/2009publications/CEC-500-2009-014/CEC-500-2009-014-D.PDF
- Charlotte J Alster, Donovan P German, Ying Lu, Steven D Allison (2013) Microbial enzymatic responses to drought and to nitrogen addition in a southern California grassland. Soil Biology and Biochemistry 64:68–79Google Scholar
- Collins M et al. (2013) Long-term climate change: projections, commitments and irreversibility. In: Stocker TF et al. (eds) Climate Change 2013: The Physical Science Basis. Contribution of Working Group 1 to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change. Cambridge University Press, Cambrige, pp. 1029–1136. doi: 10.1017/CBO9781107415324.024 Google Scholar
- D’Antonio CM (2000) Fire, plant invasions, and global changes. In: Mooney HA, Hobbs RJ (eds) Invasive species in a changing world. Island Press, Washington, D.C., pp. 65–94Google Scholar
- de Vries FT, Shade A (2013) Controls on soil microbial community stability under climate change. Front Microbiol 4. doi: 10.3389/fmicb.2013.00265
- Fox J, Weisberg S (2011) An R companion to applied regression, Second edn. Sage, Thousand OaksGoogle Scholar
- Hobbs RJ, Mooney HA (2005) Invasive species in a changing world: the interactions between global change and invasives. In: Mooney HA (ed) Invasive alien species: a new synthesis. Island Press, Washington, DCGoogle Scholar
- Hugh AL, Henry, John D Juarez, Christopher B Field, Peter M Vitousek (2005) Interactive effects of elevated CO2, N deposition and climate change on extracellular enzyme activity and soil density fractionation in a California annual grassland. Global Change Biology 11 (10):1808–1815Google Scholar
- IPCC (2012) Managing the risks of extreme events and disasters to advance climate change adaptation. Cambridge University Press, CambridgeGoogle Scholar
- KR Saiya-Cork, RL Sinsabaugh, DR Zak (2002) The effects of long term nitrogen deposition on extracellular enzyme activity in an Acer saccharum forest soil. Soil Biology and Biochemistry 34 (9):1309–1315Google Scholar
- Pysek P, Jarosik V, Hulme PE, Pergl J, Hejda M, Schaffner U, Vila M (2012) A global assessment of invasive plant impacts on resident species, communities and ecosystems: the interaction of impact measures, invading species’ traits and environment. Glob Chang Biol 18:1725–1737. doi: 10.1111/J.1365-2486.2011.02636.X CrossRefPubMedCentralGoogle Scholar
- R Core Team (2016) R: A language and environment for statistical computing. R Foundation for Statistical Computing, Vienna, AustriaGoogle Scholar
- Robert L Sinsabaugh, Christian L Lauber, Michael N Weintraub, Bony Ahmed, Steven D Allison, Chelsea Crenshaw, Alexandra R Contosta, Daniela Cusack, Serita Frey, Marcy E Gallo, Tracy B Gartner, Sarah E Hobbie, Keri Holland, Bonnie L Keeler, Jennifer S Powers, Martina Stursova, Cristina Takacs-Vesbach, Mark P Waldrop, Matthew D Wallenstein, Donald R Zak, Lydia H Zeglin, (2008) Stoichiometry of soil enzyme activity at global scale. Ecology LettersGoogle Scholar
- Sinsabaugh RL (1994) Enzymatic analysis of microbial pattern and process Biol Fert. Soils 17:69–74Google Scholar
- Stevenson, FJ, Cole, MA (1999) Cycles of soils: carbon, nitrogen, phosphorus, sulfur, micronutrients. WileyGoogle Scholar