Environmental and human factors influencing fire trends in ENSO and non-ENSO years in tropical México.

Román-Cuesta RM, Gracia M, Retana J (2003) Environmental and human factors influencing fire trends in ENSO and non-ENSO years in tropical México. Ecological Applications 13:1177-1192.

Resprouting patterns after fire and response to stool cleaning of two coexisting Mediterranean oaks with contrasting leaf habits on two different sites.

Espelta JM, Retana J, Habrouk A (2003) Resprouting patterns after fire and response to stool cleaning of two coexisting Mediterranean oaks with contrasting leaf habits on two different sites. Forest Ecology and Management 179:401-414.

An economic and ecological multi-criteria evaluation of reforestation methods to recover burned Pinus nigra forests in NE Spain.

Espelta JM, Retana J, Habrouk A (2003) An economic and ecological multi-criteria evaluation of reforestation methods to recover burned Pinus nigra forests in NE Spain. Forest Ecology and Management 180:185-198.

Seed ecology of a Mediterranean perennial herb with an exceptionally extended flowering and fruiting season

Picó F.X., Retana J. (2003) Seed ecology of a Mediterranean perennial herb with an exceptionally extended flowering and fruiting season. Botanical Journal of the Linnean Society. 142: 273-280.
Enllaç
Doi: 10.1046/j.1095-8339.2003.00172.x

Resum:

Lobularia maritima is a Mediterranean short-lived herb with a flowering and fruiting season that lasts for ten months. Previous studies have shown that recruitment in periods other than autumn of the flowering season has few demographic implications; that is contributes little to the population growth rate. Since environmental conditions in periods other than autumn would allow recruitment, we examined to what extent the seed ecology of L. maritima accounts for recruitment shortage for the greater part of the year. To this end, we studied the effects of selfing and outcrossing on seed production and germination, within- and between-year variation in seed mass and germination, seed characteristics in the soil seed bank throughout the year, and the effect of temperature as a factor controlling seed germination. Results indicate that selfing does not decrease recruitment, and thus the observed changes in visitation rate and pollinator composition throughout the year cannot account for differences in recruitment. Germinability decreases throughout the year, suggesting a possible cost in reproduction associated with extended flowering. L. maritima has a transient seed bank whose seeds also experience a decrease in their germination throughout the year. Finally, temperature affects seed germination patterns, indicating the existence of quiescence mechanisms that prevent germination in the months prior to the summer drought. Overall, the results obtained support and, at least partly, explain the recruitment patterns of L. maritima observed in the field. © 2003 The Linnean Society of London.

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