Abstract
The composition and density of soil seed banks beneath co-occurring Adenostoma fasciculatum and Ceanothus greggii shrubs from three chaparral stands last burned 9, 35 and 85 years before 1986 were investigated. The overall density of seeds in the soil, as estimated by germinations under greenhouse conditions, increased with time since fire (ca. 8000 to 25000/m2). However, this increase was due entirely to the accumulation of A. fasciculatum seed in the soil (ca. 2000 to 21000/m2). In contrast, the density of C. greggii seed was different in each of the three stands, but was not correlated with time since fire: maximum densities were recorded from the 35 year old stand (ca. 2000/m2).
A total of 31 taxa germinated and 17 occurred in sufficient numbers to be analyzed statistically. Germinable seed densities of three herb species were not influenced by soil source (beneath A. fasciculatum or C. greggii), time since fire, or the direct effects of a controlled fire treatment. Germinable seed densities of a further nine species were significantly influenced by the elapsed time since stands last burned. The densities of four decreased and five increased. Four of the species that increased in seed density over the three stands were annuals, suggesting that the chaparral sub-canopy habitat is not as unfavorable for annuals as is often assumed. The fire treatment decreased germinable seed densities of four annual species by 40–70%, but increased the germinable seed densities of the shrubs A. fasciculatum and C. greggii, and the annual Phacelia brachyloba. Our results indicate that seeds of A. fasciculatum will increase in the soil bank for at least 85 years after fire in chaparral where it is dominant. In contrast, seed reserves of C. greggii appear to be influenced primarily by site-specific patterns of seed production and by the intensity of post-dispersal seed predation.
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References
Bakker, J. P. 1985. The impact of grazing on plant communities, plant populations and soil conditions on salt marshes. Vegetatio 62: 391–398.
Brown, J. H., Reichman, O. J. & Davidson, D. W. 1979. Granivory in desert ecosystems. Ann. Rev. Ecol. Syst. 10: 201–227.
Canham, C. D. & Marks, P. L. 1985. The response of woody plants to disturbance: patterns of establishment and growth. In: Pickett, S. T. A. & White, P. S. (eds), The ecology of natural disturbance and patch dynamics, pp. 197–216. Academic Press, New York.
Cheplick, G. P. & Quinn, J. A. 1987. The role of seed depth, litter and fire in the seedling establishment of amphicarpic peanutgrass (Amphicarpum purshii). Oecologia 73: 459–464.
Christensen, N. L. & Muller, C. H. 1975a. Effects of fire on factors controlling plant growth in Adenostoma chaparral. Ecol. Monogr. 45: 29–55.
Christensen, N. L. & Muller, C. H. 1975b. Relative importance of factors controlling germination and seedling survival in Adenostoma chaparral. Am. Mid. Nat. 93: 71–78.
Cook, R. E. 1979. Patterns of juvenile mortality and recruitment in plants. In: Solbrig, O. T., Jain, S., Johnson, G. B. & Raven, P. H. (eds), Topics in plant population biology, pp. 207–231, Columbia University Press, New York.
Cook, R. E. 1980. The biology of seeds in the soil: In: Solbrig, O. T. (ed.), Demography and evolution in plant populations, pp. 107–129. Blackwell, Oxford.
Ewel, J., Berish, C., Brown, B., Price, N. & Raich, J. 1981. Slash and burn impacts on a Costa Rican wet forest site. Ecology 62: 816–829.
Freas, K. E. & Kemp, P. R. 1983. Some relationships between environmental reliability and seed dormancy in desert annual plants. J. Ecol. 71: 211–217.
Grime, J. P. 1979. Plant strategies and vegetation processes. John Wiley & Sons, New York.
Guevara, S. A. 1986. Plant species availability and regeneration in a Mexican tropical rainforest. Ph.D. Dissertation, Uppsala University.
Hassan, M. A. & West, N. E. 1986. Dynamics of soil seed pools in burned and unburned sagebrush semi-deserts. Ecology 67: 269–272.
Helsper, H. P. G. & Klerken, G. A. M. 1984. Germination of Calluna vulgaris (L.) Hull in vitro under different pH-conditions. Acta. Bot. Neerl. 33: 347–353.
Hobbs, R. J. & Gimingham, C. H. 1987. Vegetation, fire and herbivore interactions in heathland. Adv. Ecol. Res. 16: 87–173.
Hodgkinson, K. C., Harrington, G. N. & Miles, G. E. 1980. Composition, spatial and temporal variability of the soil seed pool in Eucalyptus populnea shrub woodland in central New South Wales. Aust. J. Ecol. 5, 23–29.
Hubbell, S. P. & Foster, R. B. 1986. Canopy gaps and the dynamics of a neotropical forest. In: Crawley, M. J. (ed.), Plant ecology, pp. 77–96. Blackwell, Oxford.
Hurlbert, S. H. 1984. Pseudoreplication and the design of ecological field experiments. Ecol. Monogr. 54: 187–211.
Huston, M. & Smith, T. 1987. Plant succession: life history and competition. Am. Nat. 130: 168–198.
Janzen, D. H. 1975. Intra-and inter-habitat variations in Guazuma ulmifolia (Sterculiaceae) seed predation by Amblycerus cistelinus (Bruchidae) in Costa Rica. Ecology 53: 258–261.
Keeley, J. E. 1977. Seed production, seed populations in the soil, and seedling production after fire for two congeneric pairs of sprouting and nonsprouting chaparral shrubs. Ecology 58: 820–829.
Keeley, J. E. 1986. Resilience of mediterranean shrub communities to fires. In: Dell, B., Hopkins, A. J. M. & Lamont, B. B. (eds), Resilience in mediterranean-type ecosystems, pp. 95–112. Dr W. Junk Publishers, Dordrecht.
Keeley, J. E. 1987. Role of fire in seed germination of woody taxa in California chaparral. Ecology 68: 434–443.
Keeley, J. E., Morton, B. A., Pedrosa, A. & Trotter, P. 1985. Role of allelopathy, heat and charred wood in the germination of chaparral herbs and suffrutescents. J. Ecol. 73: 445–448.
Keeley, J. E. & Keeley, S. C. 1987. Role of fire in the germination of chaparral herbs and suffrutescents. Madroño 34: 240–249.
Keeley, S. C., Keeley, J. E., Hutchinson, S. M. & Johnson, A. W. 1981. Postfire succession of the herbaceous flora in southern California chaparral. Ecology 62: 1608–1621.
Krausmann, W. J. 1981. An analysis of several variables affecting fire occurrence and size in San Diego County. Masters Thesis, San Diego State University, San Diego.
Kummerow, J. 1983. Comparative phenology of mediterranean-type plant communities. In: Kruger, F. J., Mitchell, D. T. & Jarvis, J. U. M. (eds), Mediterranean-type ecosystems: the role of nutrients, pp. 300–317. Springer-Verlag, New York.
Mallik, A. U. & Gimingham, C. H. 1983. Regeneration of heathland plants following burning. Vegetatio 53: 45–58.
Mallik, A. U., Hobbs, R. J. & Legg, C. J. 1984. Seed dynamics in Calluna-Arctostaphylos heath in north-eastern Scotland. J. Ecol. 72: 855–871.
Mills, J. N. In press. Herbivores, seed predators and chaparral succession. In: Keeley, S. C. (ed.), Proc. of the Symposium, The California chaparral: paradigms reexamined. Natural History Museum of Los Angeles County, California.
Mills, J. N. 1983. Herbivory and seedling establishment in postfire southern Californian chaparral. Oecologia 60: 267–270.
Mills, J. N. 1986. Herbivores and early postfire succession in southern California chaparral. Ecology 67: 1637–1649.
Moore, R. P. 1962. Tetrazolium as a universally acceptable quality test of viable seed. Proc. Int. Seed Test. Ass. 27: 795–805.
Price, M. V. & Reichman, O. J. 1987. Distribution of seeds in Sonoran Desert soils: implications for heteromyid rodent foraging. Ecology 68: 1797–1811.
Quick, C. R. & Quick, A. S. 1961. Germination of Ceanothus seeds Madroño 16: 23–30.
Roach, D. A. 1983. Buried seed and standing vegetation in two adjacent tundra habitats, northern Alaska. Oecologia 60: 359–364.
Schneider, R. L. & Sharitz, R. C. 1986. Seed bank dynamics in a southeastern riverine swamp. Am. J. Bot. 73: 1022–1030.
Stone, E. C. & Juhren, G. 1953. Fire stimulated germination. California Agriculture 7(9): 13–14.
Sweeney, J. R. 1956. Responses of vegetation to fire. A study of the herbaceous vegetation following chaparral fires. University of California Publ. in Botany 28: 143–221.
Templeton, A. R. & Levin, D. A. 1979. Evolutionary consequences of seed pools. Am. Nat. 114: 232–249.
Thompson, K. 1978. The occurrence of buried viable seeds in relation to environmental gradients. J. Biogeog. 5: 425–430.
Thompson, K. 1985. Buried seed banks as indicators of seed output along an altitudinal gradient. J. Biol. Educ. 19: 137–140.
Thompson, K. 1986. Small-scale heterogeneity in the seed bank of an acidic grassland. J. Ecol. 74: 733–738.
Vlahos, S. & Bell, D. T. 1986. Soil seed-bank components of the northern jarrah forest of Western Australia. Aust. J. Ecol. 11: 171–179.
Watkinson, A. R. 1986. Plant population dynamics. In: Crawley, M. (ed.), Plant ecology, pp. 137–184. Blackwell, Oxford.
Westoby, M. 1981. How diversified germination behaviour is selected. Am. Nat. 118: 882–885.
Wicklow, D. T. 1977. Germination response in Phacelia penduliflora (Hydrophyllaceae). Ecology 58: 201–205.
Young, K. R., Ewel, J. J. & Brown, B. J. 1987. Seed dynamics during forest succession in Costa Rica. Vegetatio 71: 157–173.
Zammit, C. A. & Westoby, M. 1987. Population structure and reproductive status of two Banksia shrubs at various times after fire. Vegetatio 70: 11–20.
Zedler, P. H. 1981. Vegetation change in chaparral and desert communities in San Diego Country, California. In: West, D. C., Shugart, H. H. & Botkin, D. B. (eds), Forest succession, pp. 406–430. Springer-Verlag, New York.
Zedler, P. H. & Zammit, C. A. In press. A population-based critique of concepts of change in the chaparral. In: Keeley, S. C. (ed.), Proc. of the Symposium, The California chaparral: paradigms reexamined. Natural History Museum of Los Angeles County, California.
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Zammit, C.A., Zedler, P.H. The influence of dominant shrubs, fire, and time since fire on soil seed banks in mixed chaparral. Vegetatio 75, 175–187 (1988). https://doi.org/10.1007/BF00045632
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DOI: https://doi.org/10.1007/BF00045632