Seasonal effect of three desert halophytes on soil microbial functional diversity

Abstract

The objective of this study was to evaluate the effect of some plant ecophysiological adaptations on soil microbial functional diversity in a Negev Desert ecosystem. Soil samples from the upper 0-10 cm layer were collected at the study site under three species of halophyte shrubs, Zygophyllum dumosum, Hammada scoparia, and Reaumuria negevensis. These halophytes represent the most typical cover of the Negev Desert and each of them develops complex strategies that enable greater adaptation and hence, survival. The microhabitat of the shrubs showed differences in trends and magnitude of organic matter content, electrical conductivity, total soluble nitrogen, microbial functional diversity, and C compound utilization. The trends are assumed to be driven by various mechanisms of shrub adaptation in order to be able to survive the harsh desert environment. This study provides evidence that ecophysiological strategies developed by halophytes force microbial communities (from the point of view of activity, composition, and substrate utilization) to adapt to a beneficial plant-microorganism relationship.

Key words： desert shrubs; ecophysiology; soil biota; functional diversity; desert ecosystem

References

1 Ashraf M, McNeilly T (1994). Responses of 3 arid zone grasses to N-deficiency-A greenhouse study. Arid Soil Res Rehabil, 8: 125-136

2 Bossio D, Scow K, Gunapala N, Graham K (1998). Determinants of soil microbial communities: effects of agricultural management, season, and soil type on phospholipid fatty acid profiles. Microb Ecol, 36: 1-12

3 Charley J, West N (1978). Micropattern of nitrogen mineralization activity in soils of some shrub-dominated semi desert ecosystem in Utah. Soil Biol Biochem, 9: 357-365

4 Dan J, Yaalon D, Koyumdji H, Raz Z (1972). The soil association map of Israel (1:1,000,000). Isr J Earth Sci, 2: 29-49

5 Evenari M, Shanan L, Tadmor W (1982). The Negev: The Challenge of a Desert. Cambridge: Harvard University Press, USA

6 Fisher F, Zak J, Cunningham G, Whitford W (1988). Water and nitrogen effects on growth and allocation patterns of creosotebush in the Northern Chihuahuan Desert. J Range Manage, 41: 387-391

7 Fliessbach A, Mader P (1997). Carbon source utilization by microbial communities in soils under organic and conventional farming practice. In: Insam H, Rangger A, eds. Microbial Communities Functional Versus Structural Approaches. Berlin: Springer-Verlag, 109-120

8 Garland J(1996). Patterns of potential C source utilization by rhizosphere communities. Soil Biol Biochem, 28: 223-230

9 Hadley N, Szarek S (1981). Productivity of desert ecosystems. Bioscience, 31: 747-753

10 Jackson R, Caldwell M (1993). The scale of nutrient heterogeneity around individual plants and its quantification with geostatistics. Ecology, 74: 612-614

11 Kennedy A, Smith K (1995). Soil microbial diversity and the sustainability of agricultural soils. PlantSoil, 170: 75-86

12 Kinsbursky R, Degani R, Barness G, Steinberger Y (1990). Root-microbial population dynamics in a soil profile under the canopy of the desert shrub Zygophyllum dumosum. J Arid Environ, 19: 261-267

13 Kourtev P, Ehrenfeld J, Haggblom M (2003). Experimental analysis of the effect of exotic and native plant species on the structure and function of soil microbial communities. Soil Biol Biochem, 35: 895-905

14 Lahav I, Steinberger Y (2001). Soil bacterial functional diversity in a potato field. Eur J Soil Biol, 37: 59-67

15 Lynch J, Benedetti A, Insam H, Nuti M, Smalla K, Torsvik V, Nannipieri P (2004). Microbial diversity in soil: ecological theories, the contribution of molecular techniques and the impact of transgenic plants and transgenic microorganisms. Biol Fertil Soils, 40: 363-385

16 Marilley L, Aragno M (1999). Phylogenetic diversity of bacterial communities differing in degree of proximity of Lolium perenne and Trifolium repens roots. Appl Soil Ecol, 13: 127-136

17 Mills A, Wasser R (1980). Aspects of diversity measurement for microbial communities. Appl Environ Microbiol, 41: 578-586

18 Nannipieri P, Ascher J, Ceccherini M, Landi L, Pietramellara G, Renella G (2003). Microbial diversity and soil functions. Eur J Soil Sci, 54: 655-670

19 Noy-Meir I (1973). Desert ecosystems: Environment and producers. Ann Rev Ecol Syst, 4: 25-51

20 Noy-Meir I (1985). Desert ecosystem structure and function. In: Evenari M, Noy-Meir I, Goodall D, eds. Hot Desert and Arid Shrub-lands. Ecosystems of the World. Amsterdam: Elsevier Science Publishers, 93-104

21 Powlson D, Brookes P, Christensen B (1987). Measurement of soil microbial biomass provides an early indication of changes in the total soil organic matter due to straw incorporation. Soil Biol Biochem, 19: 159-164

22 S.F.A.S. (1995). Manual-San Plus Analyzer. Breda: The Netherlands: SKALAR Analytical

23 Sarig S, Steinberger Y (1994). Microbial biomass response to seasonal fluctuation in soil salinity under the canopy of desert halophytes. Soil Biol Biochem, 26: 1405-1408

24 Sarig S, Barness G, Steinberger Y (1994). Annual plant-growth and soil characteristics under desert halophyte canopy. Acta Oecol, 15: 521-527

25 Shmida A, Evenari M, Noy-Meir I (1986). Hot desert ecosystems. An integrated view. In: Evenari M, Noy-Meir I, Goodall D, eds. Ecosystems of the World: Hot Deserts and Arid Shrublands. Amsterdam: Elsevier Science Publishers, 379-387

26 Skujins J (1984). Microbial ecology of desert soils. Adv Microb Ecol, 7: 49-91

27 Sokal R, Rohlf F (1981). Biometry, Principles, Practices and Statistics in Biological Research, 2nd edition. San Francisco: W. H. Freeman and Co., USA

28 Steinberger Y, Shmida A, Whitford W (1990). Decomposition along a rainfall gradient in the Judean Desert, Israel. Oecologia, 82: 322-324

29 ter Braak C (1995). Ordination (Chapter 5). In: Jongman R H G, ter Braak C, Van Tongeren O, eds. Data Analysis in Community and Landscape Ecology. Cambridge: Cambridge University Press, UK, 91-173

30 Torsvik V, Ovreas L, Thingstad T (2002). Prokaryotic diversity- Magnitude, dynamics, and controlling factors. Science, 296: 1064-1066

31 Vahjen W, Munch J, Tebbe C (1995). Carbon source utilisation of soil extracted microorganisms as a tool to detect the effects of soil supplemented with genetically-engineered and non-engineered Corynebacterium glutamicum and a recomibinant peptide at the community level. FEMS Microbiol Ecol, 18: 317-328

32 von Wintzingerode F, Gobel U, Stackebrandt E (1997). Determination of microbial diversity in environmental samples: pitfalls of PCR-based rRNA analysis. FEMS Microbiol Rev, 21: 213-229

33 West N, Skujins J (1978). Nitrogen in Desert Ecosystems, US/IBP no. 9. Dowden, Hutchinson and Ross, Stroudsburg, USA

34 Westover K, Kennedy A, Kelley S (1997). Patterns of rhizosphere microbial community structure associated with co-occurring plant species. J Ecol, 85: 863-873

35 Whitford W (1986). Pattern in desert ecosystem: Water availability and nutrient interactions. In: Dubinsky Z, Steinberger Y, eds. Environmental Quality and Ecosystem Stability. Ramat Gan: Bar-Ilan University Press, Israel, 109-117

36 Whitford W, Steinberger Y, Mackay W, Parker L, Freckman D, Wallwork J, Weems D (1986). Rainfall and decomposition in the Chihuahuan Desert. Oecologia, 68: 512-515

37 Wilson E (1988). Biodiversity. Washington: National Academy Press, USA

38 Zak J, Willig M, Moorhead D, Wildman H (1994). Functional diversity of microbial communities: a quantitative approach. Soil Biol Biochem, 26: 1101-1108

39 Zak J, Sinsabaugh R, MacKay W (1995). Windows of opportunity in desert ecosystems: their implication to fungal community development. Can J Bot, 73: S1407-S1414