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Role of seed banks in the dynamics of desert communities

  • M. Ajmal Khan
  • Farhat Agha
  • Bilquees Gul

Abstract

Sub-tropical deserts of Karachi, Pakistan are dominated by perennial shrubs and grasses, usually in a mono-specific stands. Seed bank dynamics of three stands about a kilometer away from the coast were selected and monitored for 2 years. These stands were dominated by Atriplex stocksii, Cyperus arenarius and Cressa cretica, respectively, with few individuals of other species in each stand. Soil analysis of the C. arenarius community showed seeds of A. stocksii and C. arenarius were present throughout both of the seasons; however, only A. stocksii maintained a persistent seed bank that had some relationship with the aboveground vegetation. The C. cretica dominated community had a substantial presence of C. arenarius seed in the soil with some seeds of C. cretica, Salsola imbricata and A. stocksii. However, C. cretica maintained a small persistent seed bank showing a close relationship between seed bank and vegetation. A. stocksii maintained a large persistent seed bank during both seasons indicating a good seed bank-vegetation relationship.

Keywords

Salt Marsh Seed Bank Aboveground Vegetation Perennial Shrub Persistent Seed Bank 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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References

  1. 1.
    Ungar IA (2001) Seed bank and seed population dynamics of halophytes. Wetland Ecol Manag 9: 499–510CrossRefGoogle Scholar
  2. 2.
    Bertness MD, Gough L, Shumway SW (1992) Salt tolerance and the distribution of fugitive salt marsh plants. Ecology 73: 1842–1851CrossRefGoogle Scholar
  3. 3.
    Gulzar S, Khan MA (1994) Seed banks of coastal shrub communities. Ecoprint 1: 1–6Google Scholar
  4. 4.
    Aziz S, Khan MA (1995) Role of disturbance of the seed bank and demography of Leucus urticifolia (Labiatae) population in a maritime subtropical desert of Pakistan. Int J Plant Sci 156: 834–840CrossRefGoogle Scholar
  5. 5.
    Cantero JJ, Leon R, Cisneros JM, Cantero A (1998) Habitat structure and vegetation relationships in central Argentina salt marsh landscapes. Plant Ecol 137: 79–100CrossRefGoogle Scholar
  6. 6.
    Shiferaw H, Teketay D, Nemomissa S, Assefa F (2005) Some biological characteristics that foster the invasion of Prosopis juliflora (SW.) DC at middle east Rift Valley Area, north eastern Ethiopia. J Arid Environ 58: 135–154CrossRefGoogle Scholar
  7. 7.
    Wang SM, Zhang X, Li Y, Zhang L, Xiong YC, Wang G (2005) Spatial distribution patterns of the soil seed bank of Stipagrostis pinnata (Trin.) de Winter in the Gurbantonggut Desert of north-west China. J Arid Environ 63: 203–222CrossRefGoogle Scholar
  8. 8.
    Ungar IA (1995) Seed bank ecology of halophytes. In: MA Khan, IA Ungar (eds): Biology of Salt Tolerant Plants. University of Karachi, Pakistan, 65–79Google Scholar
  9. 9.
    Jutila HME (1998) Effect of different treatments on the seed bank of grazed and ungrazed Baltic seashore meadows. Can J Bot 76: 1188–1197CrossRefGoogle Scholar
  10. 10.
    Jutila HME (1998) Seed banks of grazed and ungrazed Baltic seashore meadows. J Veg Sci 9: 395–408CrossRefGoogle Scholar
  11. 11.
    Jerling L (1984) Composition and viability of the seed bank along a successional gradient on a Baltic Sea shore meadow. Holarctic Ecol 6: 150–156Google Scholar
  12. 12.
    Jefferies RL, Davy AJ, Rudmick J (1981) Population biology of the salt marsh annual Sali-cornia europaea agg. J Ecol 69: 17–31CrossRefGoogle Scholar
  13. 13.
    Hartman JM (1988) Recolonization of small disturbance patches in a New England salt marsh. Am J Bot 75: 1625–1631CrossRefGoogle Scholar
  14. 14.
    Hopkins DR, Parker VT (1984) A study of the seed bank of a salt marsh in northern San Francisco Bay. Am J Bot 71: 348–355CrossRefGoogle Scholar
  15. 15.
    Valiela I, Rietsma CS (1995) Disturbance of salt marsh vegetation by wrack mats in Great Sippewissett Marsh. Oecologia 102: 106–112Google Scholar
  16. 16.
    Badger KS, Ungar IA (1990) Seedling competition and the distribution of Hordeum jubatum L. along a soil salinity gradient. Funct Ecol 4: 639–644CrossRefGoogle Scholar
  17. 17.
    Badger KS, Ungar IA (1994) Seed bank dynamics in an inland salt marsh with special emphasis on the halophyte Hordeum jubatum L. Int J Plant Sci 155: 66–72CrossRefGoogle Scholar
  18. 18.
    Egan TP, Ungar IA (2000) Similarity between seed banks and aboveground vegetation along a salinity gradient. J Veg Sci 11: 189–194CrossRefGoogle Scholar
  19. 19.
    Hutchings MJ, Russell PJ (1989) The seed regeneration dynamics of an emergent salt marsh. J Ecol 77: 615–637CrossRefGoogle Scholar
  20. 20.
    Ungar IA, Woodell SRJ (1993) The relationship between the seed bank and species composition of plant communities in two British salt marshes. J Veg Sci 4: 531–536CrossRefGoogle Scholar
  21. 21.
    Ungar IA, Woodell SRJ (1996) Similarity of seed bank to the aboveground vegetation in grazed and ungrazed salt marsh communities on the Gower Peninsula, South Wales. Int J Plant Sci 157: 746–749CrossRefGoogle Scholar
  22. 22.
    Zaman AU, Khan MA (1992) The role of buried viable seeds in a saline desert plant community. Bangladesh J Bot 21:1–10Google Scholar
  23. 23.
    Khan MA (1993) Relationship of seed bank to plant distribution in saline arid communities. Pak J Bot 25: 73–82Google Scholar
  24. 24.
    Khan MA (1990) The relationship of seed bank to vegetation in a saline desert community. In: DN Sen, S Mohammad (eds): Proceedings International Seed Symposium, Jodhpur, India, 87–92Google Scholar
  25. 25.
    Aziz S, Khan MA (1996) Seed bank dynamics of a semiarid coastal shrub community in Pakistan. J Arid Environ 34: 81–87CrossRefGoogle Scholar
  26. 26.
    Gul B, Khan MA (2001) Seasonal seed bank patterns of an Arthrocnemum macrostachyum (Chenopodiaceae) community along a coastal marsh inundation gradient on the Arabian Sea near Karachi, Pakistan. Pak J Bot 33: 305–314Google Scholar
  27. 27.
    Cottam G, Curtis JT (1956) The use of distance measurements in phytosociology sampling. Ecology 37: 451–460CrossRefGoogle Scholar
  28. 28.
    Khan MA, Gul B (1999) Seed bank strategies of coastal populations at Arabian Sea coast. In: ED McArthur, WK Ostler, CL Wambolt (eds): Proceedings of the symposium on Shrubland Ecotones. Proceedings RMRS-P-11, Ogden, UT: US. Department of Agriculture, Forest Service, Rocky Mountain Research Station USA, 227–230Google Scholar
  29. 29.
    Gul B, Weber DJ (2001) Seed bank dynamics in a Great Basin salt playa. J Arid Environ 49: 785–794CrossRefGoogle Scholar
  30. 30.
    Adam MA, Marsh DM, Knox JS (2005) Importance of seed bank for population viability and population monitoring in a threatened wetland herb. Biol Conserv 124: 425–436CrossRefGoogle Scholar
  31. 31.
    Jutila HME (2002) Seed banks of river delta meadows on the west coast of Finland. Ann Bot Fennici 39: 49–61Google Scholar
  32. 32.
    Ungar IA (1978) Halophyte seed germination. Bot Rev 44: 2333–2264CrossRefGoogle Scholar
  33. 33.
    Woodell SRJ (1985) Salinity and seed germination in coastal plants. Vegetatio 61:223–230CrossRefGoogle Scholar
  34. 34.
    Keiffer CH, Ungar IA (1997) The effect of extended exposure to hypersaline conditions on the germination of five inland halophyte species. Am J Bot 84: 104–111CrossRefGoogle Scholar
  35. 35.
    Khan MA, Ungar IA (1997) Effects of thermoperiod on recovery of seed germination of halophytes from saline conditions. Am J Bot 84: 279–283CrossRefGoogle Scholar
  36. 36.
    Dodd GL, Donovan LA (1999) Water potential and ionic effects on germination and seedling growth of two cold desert shrubs. Am J Bot 86: 1146–1153PubMedCrossRefGoogle Scholar
  37. 37.
    Ungar IA (1987) Population ecology of halophyte seeds. Bot Rev 53: 301–334CrossRefGoogle Scholar
  38. 38.
    Pugnaire FI, Lazaro R (2000) Seed bank and understory species composition in a semi-arid environment: The effect of shrub age and rainfall. Ann Bot 86: 807–813CrossRefGoogle Scholar
  39. 39.
    Boudell JA, Link SO, Johansen JR (2002) Effect of soil microtopography on seed bank distribution in the shrub-steppe. West N Am Natur 62:14–24Google Scholar
  40. 40.
    Khan MA, Ungar IA (1986) Life history and population dynamics of Atriplex triangularis. Vegetatio 66: 17–25CrossRefGoogle Scholar

Copyright information

© Birkhäuser Verlag/Switzerland 2008

Authors and Affiliations

  • M. Ajmal Khan
    • 1
  • Farhat Agha
    • 1
  • Bilquees Gul
    • 1
  1. 1.Department of BotanyUniversity of KarachiKarachiPakistan

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