Oecologia

, Volume 184, Issue 1, pp 267–277 | Cite as

Chronic N enrichment and drought alter plant cover and community composition in a Mediterranean-type semi-arid shrubland

Community ecology – original research

Abstract

Anthropogenic nitrogen (N) deposition has caused a decline in native plant species and an increase in exotic plant species in many terrestrial ecosystems; however, vegetation change depends on the rate and/or duration of N input, individual species responses, interactions with other resources, and ecosystem properties such as species richness and canopy cover, soil texture, pH, and/or disturbance regime. Native shrub and exotic forb responses to N enrichment were evaluated over a 13-year field experiment in a mature coastal sage scrub (CSS) shrubland of southern California to test the hypothesis that dry-season N input will cause a decline in native shrubs and an increase in exotic annuals. Nitrogen enrichment caused the dominant native shrubs, Artemisia californica and Salvia mellifera, to respond differently, with A. californica initially increasing with N input but declining thereafter and S. mellifera declining consistently over the 13-year-period. Both species exhibited higher canopy dieback during drought conditions, especially in N plots. Brassica nigra, an exotic annual, invaded N plots significantly more than control plots, but only after 10 years of N addition and a prolonged drought, which increased native shrub canopy dieback. These results indicate a possible synergism between N enrichment and drought on native shrub and exotic forb abundance, which would have important implications for plant diversity in semi-arid shrublands of southwest US that are anticipated to experience an increase in anthropogenic N enrichment and the frequency and duration of drought.

Keywords

Anthropogenic N deposition Chaparral Climate change Coastal sage scrub Exotic species invasion 

Notes

Acknowledgements

This research was supported in part by the National Science Foundation-CAREER (DEB-0133259), National Institutes of Health- National Institute of General Medical Science-SCORE (S06 GM 59833), and the United States Department of Agriculture-National Institute of Food and Agriculture-HSI (2010-38422-21241) programs. Permission to use the Santa Margarita Ecological Reserve was graciously granted by the San Diego State University Field Station Programs.

Author contribution statement

GLV conceived, designed, and performed the experiments, analyzed the data, and wrote the manuscript.

References

  1. Allen EB, Egerton-Warburton LM, Hilbig BE, Valliere JM (2016) Interactions of arbuscular mycorrhizal fungi, critical loads of nitrogen deposition, and shifts from native to invasive species in a southern California shrubland. Botany 94:425–433. doi: 10.1139/cjb-2015-0266 CrossRefGoogle Scholar
  2. Bobbink R, Hicks K, Galloway J et al (2010) Global assessment of nitrogen deposition effects on terrestrial plant diversity: a synthesis. Ecol Appl 20(1):30–59CrossRefPubMedGoogle Scholar
  3. Bonham CD (1989) Measurements of terrestrial vegetation. John Wiley, New York, p 338Google Scholar
  4. Bozzolo FH, Lipson DA (2013) Differential responses of native and exotic coastal sage scrub plant species to N additions and the soil microbial community. Plant Soil 371:37–51. doi: 10.1007/s11104-013-1668-2 CrossRefGoogle Scholar
  5. Bytnerowicz A, Fenn ME (1996) Nitrogen deposition in California forests: a review. Environ Pollut 92:127–146CrossRefPubMedGoogle Scholar
  6. Cleland EE, Harpole WS (2010) Nitrogen enrichment and plant communities. Ann NY Acad Sci 1195:46–61. doi: 10.1111/j.1749-6632.2010.05458.x CrossRefPubMedGoogle Scholar
  7. Cox P, Delao A, Komorniczak A, Weller R (2009) The California almanac of emissions and air quality, 2009. Air resources board. California Environmental Protection Agency, SacramentoGoogle Scholar
  8. Cox RD, Preston KL, Johnson RF, Minnich RA, Allen EB (2014) Influence of landscape-scale variables on vegetation conversion to exotic annual grassland in southern California, USA. Glob Ecol Conser 2:190–203. doi: 10.1016/j.gecco.2014.09.008 CrossRefGoogle Scholar
  9. D’Antonio CM, Vitousek PM (1992) Biological invasions by exotic grasses, the grass fire cycle, and global change. Annu Rev Ecol Syst 23:63–87CrossRefGoogle Scholar
  10. Fenn ME, Poth MA (2004) Monitoring nitrogen deposition in throughfall using ion exchange resin columns: a field test in the San Bernardino mountains. J Environ Qual 33:2007–2014CrossRefPubMedGoogle Scholar
  11. Fenn ME, Haeuber R, Tonnesen GS et al (2003) Nitrogen emissions, deposition, and monitoring in the western United States. Bioscience 53:391–403CrossRefGoogle Scholar
  12. Fenn ME, Allen EB, Weiss SB et al (2010) Nitrogen critical loads and management alternatives for N-impacted ecosystems in California. J Environ Manage 91:2404–2423. doi: 10.1016/j.jenvman.2010.07.034 CrossRefPubMedGoogle Scholar
  13. Galloway JN, Dentener FJ, Capone DG et al (2004) Nitrogen cycles: past, present, and future. Biogeochemistry 70:153–226CrossRefGoogle Scholar
  14. Garfin G, Franco G, Blanco H et al (2014) Ch. 20: Southwest. Climate change impacts in the United States: the third national climate assessment. Melillo JM, Richmond TC, Yohe GW (Eds) US: Global Change Research Program, 462–486, doi:10.7930/J08G8HMNGoogle Scholar
  15. Gea-Izquierdo G, Gennet S, Bartolome JW (2007) Assessing plant–nutrient relationships in highly invaded Californian grasslands using non-normal probability distributions. Appl Veg Sci 10:343–350. doi:10.1658/1402-2001(2007)10[343:APRIHI]2.0.CO;2Google Scholar
  16. Gray JT, Schlesinger WH (1983) Nutrient use by evergreen and deciduous shrubs in southern California. II. Experimental investigations of the relationship between growth, nitrogen uptake, and nitrogen availability. J Ecol 71:43–56CrossRefGoogle Scholar
  17. Harpole WS, Potts DL, Suding KN (2007) Ecosystem responses to water and nitrogen amendment in a California grassland. Glob Change Biol 13:1–8. doi: 10.1111/j.1365-2486.2007.01447.x CrossRefGoogle Scholar
  18. Hintze J (2007) NCSS and PASS. Number Cruncher Statistical Systems, Kaysville. http://www.NCSS.com. Accessed 1 June 2011
  19. Homyak PM, Blankinship JC, Marchus K, Lucero DM, Sickman JO, Schimel JP (2016) Aridity and plant uptake interact to make dryland soils hotspots for nitric oxide (NO) emissions. PNAS 113:E2608–E2616. doi: 10.1073/pnas.1520496113 CrossRefPubMedPubMedCentralGoogle Scholar
  20. Isbell F, Reich PB, Tilman D et al (2013) Nutrient enrichment, biodiversity loss, and consequent declines in ecosystem productivity. Proc Natl Acad Sci 110:11911–11916. doi: 10.1073/pnas.1310880110 CrossRefPubMedPubMedCentralGoogle Scholar
  21. Keeley JE, Brennan TJ (2012) Fire-driven alien invasion in a fire-adapted ecosystem. Oecologia 169:1043–1052. doi: 10.1007/s00442-012-2253-8 CrossRefPubMedGoogle Scholar
  22. Kimball S, Goulden ML, Suding KN, Parker S (2014) Altered water and nitrogen input shifts succession in a Southern California coastal sage community. Ecol Appl 24:1390–1404CrossRefGoogle Scholar
  23. Knecht AA (1971) Soil survey for Western riverside area California. United States Department of Agriculture, Soil Conservation Service, WashingtonGoogle Scholar
  24. Kolb KJ, Davis SD (1994) Drought tolerance and xylem embolism in co-occurring species of coastal sage and chaparral. Ecology 75:648–659CrossRefGoogle Scholar
  25. Milchunas DG, Lauenroth WK (1995) Inertia in plant community structure: state changes after cessation of nitrogen-enrichment stress. Ecol Appl 5:452–458CrossRefGoogle Scholar
  26. Minnich RA, Dezzani RJ (1998) Historical decline of coastal sage scrub in the Riverside-Perris Plain California. Western Birds 29:366–391Google Scholar
  27. Myers N, Mittermeier RA, Mittermeier CG et al (2000) Biodiversity hotspots for conservation priorities. Nature 403:853–858CrossRefPubMedGoogle Scholar
  28. Naeem S, Knops JMH, Tilman D, Howe KM, Kennedy T, Gale S (2000) Plant diversity increases resistance to invasion in the absence of covarying extrinsic factors. Oikos 91:97–108CrossRefGoogle Scholar
  29. Padgett PE, Allen EB (1999) Differential responses to nitrogen fertilization in native shrubs and exotic annuals common to Mediterranean coastal sage scrub of California. Plant Ecol 144:93–101CrossRefGoogle Scholar
  30. Pearce ISK, Van der Wal R (2008) Interpreting nitrogen pollution thresholds for sensitive habitats: the importance of concentration versus dose. Environ Pollut 152:253–256CrossRefPubMedGoogle Scholar
  31. Phoenix GK, Hicks WK, Cinderby S et al (2006) Atmospheric nitrogen deposition in world biodiversity hotspots: the need for a greater global perspective in assessing N deposition impacts. Glob Change Biol 12:470–476. doi: 10.1111/j.1365-2486.2006.01104.x CrossRefGoogle Scholar
  32. Pivovaroff AL, Santiago LS, Vourlitis GL, Grantz DA, Allen MF (2016) Differing hydraulic response strategies of four Mediterranean-type shrubs to long-term dry season nitrogen deposition. Oecologia. doi: 10.1007/s00442-016-3609-2 PubMedGoogle Scholar
  33. Pratt JD, Mooney KA (2013) Clinal adaptation and adaptive plasticity in Artemisia californica: implications for the response of a foundation species to predicted climate change. Glob Change Biol 19:2454–2466. doi: 10.1111/gcb.12199 CrossRefGoogle Scholar
  34. Rao LE, Allen EB (2010) Combined effects of precipitation and nitrogen deposition on native and invasive winter annual production in California deserts. Oecologia 162:1035–1046. doi: 10.1007/S00442-009-1516-5 CrossRefPubMedGoogle Scholar
  35. Rao LE, Steers RJ, Allen EB (2011) Effects of natural and anthropogenic gradients on native and exotic winter annuals in a southern California desert. Plant Ecol 212:1079–1089. doi: 10.1007/s11258-010-9888-5 CrossRefGoogle Scholar
  36. Read DJ, Perez-Moreno J (2003) Mycorrhizas and nutrient cycling in ecosystems—a journey towards relevance? New Phytol 157:475–492CrossRefGoogle Scholar
  37. Roem WJ, Klees H, Berendse F (2002) Effects of nutrient addition and acidification on plant species diversity and seed germination in heathland. J Appl Ecol 39:937–948CrossRefGoogle Scholar
  38. Seabloom EW, Harpole WS, Reichmann OJ, Tilman D (2003) Invasion, competitive dominance, and resource use by exotic and native California grassland species. Proc Natl Acad Sci 100:13384–13389CrossRefPubMedPubMedCentralGoogle Scholar
  39. Sigüenza C, Crowley DE, Allen EB (2006) Soil microorganisms of a native shrub and exotic grasses along a nitrogen deposition gradient in southern California. Appl Soil Ecol 32:13–26. doi: 10.1016/j.apsoil.2005.02.015 CrossRefGoogle Scholar
  40. Simkin SM, Allen EB, Bowman WD et al (2016) Conditional vulnerability of plant diversity to atmospheric nitrogen deposition across the United States. Proc Natl Acad Sci. 113:4086–4091. doi: 10.1073/pnas.1515241113 CrossRefPubMedPubMedCentralGoogle Scholar
  41. Suding KN, Collins SL, Gough L et al (2005) Functional and abundance-based mechanisms explain diversity loss due to N fertilization. Proc Natl Acad Sci USA 102:4387–4392. doi: 10.1073/pnas.0408648102 CrossRefPubMedPubMedCentralGoogle Scholar
  42. Talluto MV, Suding KN (2008) Historical change in coastal sage scrub in southern California, USA in relation to fire frequency and air pollution. Landsc Ecol 23:803–815. doi: 10.1007/s10980-008-9238-3 CrossRefGoogle Scholar
  43. Valliere JM, Allen EB (2016) Interactive effects of nitrogen deposition and drought-stress on plant–soil feedbacks of Artemisia californica seedlings. Plant Soil 403:277–290. doi: 10.1007/s11104-015-2776-y CrossRefGoogle Scholar
  44. Vitousek PM, Howarth RW, Likens GE et al (1997) Human alteration of the global nitrogen cycle: sources and consequences. Ecol Appl 7:737–750Google Scholar
  45. Vourlitis GL (2012) Aboveground net primary production response of semi-arid shrublands to chronic experimental dry-season N input. Ecosphere 3:1–9. doi: 10.1890/ES11-00339.1 CrossRefGoogle Scholar
  46. Vourlitis GL, Fernandez JS (2012) Changes in the soil, litter, and vegetation nitrogen and carbon concentrations of semiarid shrublands in response to chronic dry season nitrogen input. J Arid Environ 82:115–122. doi: 10.1016/j.jaridenv.2012.02.006 CrossRefGoogle Scholar
  47. Vourlitis GL, Hentz CS (2016) Chronic N addition alters the carbon and nitrogen storage of a post-fire Mediterranean-type shrubland. J Geophys Res-Biogeosci. 121:385–398. doi: 10.1002/2015JG003220 CrossRefGoogle Scholar
  48. Vourlitis GL, Pasquini S (2009) Experimental dry-season N deposition alters species composition in southern Californian Mediterranean-type shrublands. Ecology 90:2183–2189CrossRefPubMedGoogle Scholar
  49. Vourlitis GL, Pasquini S, Mustard R (2009) Effects of dry-season N input on the productivity and N storage of Mediterranean-type shrublands. Ecosystems 12:473–488. doi: 10.1007/s10021-009-9236-6 CrossRefGoogle Scholar
  50. Westman WE (1983) Xeric Mediterranean-Type Shrubland Associations of Alta and Baja California and the Community/Continuum Debate. Vegetatio 52:3–19Google Scholar
  51. Wood YA, Meixner T, Shouse PJ, Allen EB (2006) Altered ecohydrologic response drives native shrub loss under conditions of elevated nitrogen deposition. J Environ Qual 35:76–92. doi: 10.2134/jeq2004.0465 CrossRefPubMedGoogle Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 2017

Authors and Affiliations

  1. 1.California State UniversitySan MarcosUSA

Personalised recommendations