Drought advances spring growth phenology of the Mediterranean shrub Erica multiflora

Bernal M., Estiarte M., Peñuelas J. (2011) Drought advances spring growth phenology of the Mediterranean shrub Erica multiflora. Plant Biology. 13: 252-257.
Enllaç
Doi: 10.1111/j.1438-8677.2010.00358.x

Resum:

Current climate projections predict drier and warmer conditions in the Mediterranean basin over the next century. While advanced spring growth due to warming has been described in the literature, few data are available on the effects of drought on phenology. Hence, the phenology and growth of two Mediterranean shrubs, Erica multiflora and Globularia alypum, was studied in a rainfall exclusion field experiment to simulate spring drought in a natural shrubland. We estimated the onset of growth in spring by monitoring the appearance of new stems, and the end of growth in summer by following the elongation of stems. Drought treatment caused earlier onset of the spring growing season in E. multiflora, whereas no advance was observed in G. alypum. However, growth cessation was not affected in E. multiflora. Drought reduced the growth of both shrubs, as reflected in less stem elongation. The results show that a drier climate might affect not only growth but also spring phenology of some Mediterranean species. We suggest that a reduction in the cooling effect of transpiration may have analogous effects to warming and might advance the start of growth in E. multiflora, a species whose phenology has been described as warming-sensitive. The lengthening of the growing season resulting from advanced growth did not imply higher productivity, as growth was restricted by drought. © 2010 German Botanical Society and The Royal Botanical Society of the Netherlands.

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Large delay in flowering in continental versus coastal populations of a Mediterranean shrub, Globularia alypum

Estiarte M., Puig G., Peñuelas J. (2011) Large delay in flowering in continental versus coastal populations of a Mediterranean shrub, Globularia alypum. International Journal of Biometeorology. 55: 855-865.
Enllaç
Doi: 10.1007/s00484-011-0422-9

Resum:

Globularia alypum is a perennial shrub typical of western Mediterranean thermophilous shrublands. Nine populations of G. alypum located in different localities of Catalonia (NE Spain) were surveyed for flowering phenology. Flower-head buds were present in all the populations in July. Flowering time in the area spans from the late summer-early autumn to the next spring depending on the populations; there are two groups of populations, early and late flowering. Early populations grow mostly in coastal localities and flower from September to November, whereas late flowering populations grow in inland localities and flower from February to April. The flowering order of the populations correlated with minimum temperature of most months except the warmest ones, and correlated with maximum and mean temperatures of the coldest months. Correlations were similar when tested with annual climate. The flowering order also correlated with the thermic interval for most months except the coldest and with the index of continentality. Early populations alone did not present correlations with any variable, whereas late populations alone correlated similarly to all populations together. Flowering order did not correlate with precipitation. Late populations are proposed to be regulated by temperature according to our results whereas early populations could be regulated by timing in precipitation after summer drought, according to published results. We discuss the possibilities of the two flowering patterns, early and late, being due to phenotypic plasticity or to genetic adaptation to local climates. We also discuss the consequences at the plant and ecosystem level of climate warming causing shifts from late to early patterns, a possibility that is likely in the warmest of the late populations if flowering is modulated phenotypically. © 2011 ISB.

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The world's largest database on wild plants is published.

Sardans J, Peñuelas J, Estiarte M, Ogaya R, Llusià J (2011) The world's largest database on wild plants is published. UABdivulga 09/2011.

Llebot E. (ed). Impactes, vulnerabilitat i retroalimentacions climàtiques als ecosistemes terrestres catalans. Segon informe sobre el canvi climàtic a Catalunya.

Peñuelas J, Filella I, Estiarte M, Ogaya R, Llusià J, Sardans J, Jump A, Curiel J, Carnicer J, Rutishauser T, Rico L, Keenan T, Garbulsky M, Coll M, Diaz de Quijano M, Seco R, Rivas-Ubach A, Silva J, Boada M, Stefanescu C, Lloret F, Terradas J (2011) Llebot E. (ed). Impactes, vulnerabilitat i retroalimentacions climàtiques als ecosistemes terrestres catalans. Segon informe sobre el canvi climàtic a Catalunya. Institut d'Estudis Catalans i Generalitat de Catalunya. Barcelona, pp. 373-407.

TRY - a global database of plant traits

Kattge J., Diaz S., Lavorel S., Prentice I.C., Leadley P., Bonisch G., Garnier E., Westoby M., Reich P.B., Wright I.J., Cornelissen J.H.C., Violle C., Harrison S.P., Van Bodegom P.M., Reichstein M., Enquist B.J., Soudzilovskaia N.A., Ackerly D.D., Anand M., Atkin O., Bahn M., Baker T.R., Baldocchi D., Bekker R., Blanco C.C., Blonder B., Bond W.J., Bradstock R., Bunker D.E., Casanoves F., Cavender-Bares J., Chambers J.Q., Chapin F.S., Chave J., Coomes D., Cornwell W.K., Craine J.M., Dobrin B.H., Duarte L., Durka W., Elser J., Esser G., Estiarte M., Fagan W.F., Fang J., Fernandez-Mendez F., Fidelis A., Finegan B., Flores O., Ford H., Frank D., Freschet G.T., Fyllas N.M., Gallagher R.V., Green W.A., Gutierrez A.G., Hickler T., Higgins S.I., Hodgson J.G., Jalili A., Jansen S., Joly C.A., Kerkhoff A.J., Kirkup D., Kitajima K., Kleyer M., Klotz S., Knops J.M.H., Kramer K., Kuhn I., Kurokawa H., Laughlin D., Lee T.D., Leishman M., Lens F., Lenz T., Lewis S.L., Lloyd J., Llusia J., Louault F., Ma S., Mahecha M.D., Manning P., Massad T., Medlyn B.E., Messier J., Moles A.T., Muller S.C., Nadrowski K., Naeem S., Niinemets U., Nollert S., Nuske A., Ogaya R., Oleksyn J., Onipchenko V.G., Onoda Y., Ordonez J., Overbeck G., Ozinga W.A., Patino S., Paula S., Pausas J.G., Penuelas J., Phillips O.L., Pillar V., Poorter H., Poorter L., Poschlod P., Prinzing A., Proulx R., Rammig A., Reinsch S., Reu B., Sack L., Salgado-Negret B., Sardans J., Shiodera S., Shipley B., Siefert A., Sosinski E., Soussana J.-F., Swaine E., Swenson N., Thompson K., Thornton P., Waldram M., Weiher E., White M., White S., Wright S.J., Yguel B., Zaehle S., Zanne A.E., Wirth C. (2011) TRY - a global database of plant traits. Global Change Biology. 17: 2905-2935.
Enllaç
Doi: 10.1111/j.1365-2486.2011.02451.x

Resum:

Plant traits - the morphological, anatomical, physiological, biochemical and phenological characteristics of plants and their organs - determine how primary producers respond to environmental factors, affect other trophic levels, influence ecosystem processes and services and provide a link from species richness to ecosystem functional diversity. Trait data thus represent the raw material for a wide range of research from evolutionary biology, community and functional ecology to biogeography. Here we present the global database initiative named TRY, which has united a wide range of the plant trait research community worldwide and gained an unprecedented buy-in of trait data: so far 93 trait databases have been contributed. The data repository currently contains almost three million trait entries for 69000 out of the world's 300000 plant species, with a focus on 52 groups of traits characterizing the vegetative and regeneration stages of the plant life cycle, including growth, dispersal, establishment and persistence. A first data analysis shows that most plant traits are approximately log-normally distributed, with widely differing ranges of variation across traits. Most trait variation is between species (interspecific), but significant intraspecific variation is also documented, up to 40% of the overall variation. Plant functional types (PFTs), as commonly used in vegetation models, capture a substantial fraction of the observed variation - but for several traits most variation occurs within PFTs, up to 75% of the overall variation. In the context of vegetation models these traits would better be represented by state variables rather than fixed parameter values. The improved availability of plant trait data in the unified global database is expected to support a paradigm shift from species to trait-based ecology, offer new opportunities for synthetic plant trait research and enable a more realistic and empirically grounded representation of terrestrial vegetation in Earth system models. © 2011 Blackwell Publishing Ltd.

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Drought-resistant fungi control soil organic matter decomposition and its response to temperature

Yuste J.C., Peñuelas J., Estiarte M., Garcia-Mas J., Mattana S., Ogaya R., Pujol M., Sardans J. (2011) Drought-resistant fungi control soil organic matter decomposition and its response to temperature. Global Change Biology. 17: 1475-1486.
Enllaç
Doi: 10.1111/j.1365-2486.2010.02300.x

Resum:

Microbial-mediated decomposition of soil organic matter (SOM) ultimately makes a considerable contribution to soil respiration, which is typically the main source of CO2 arising from terrestrial ecosystems. Despite this central role in the decomposition of SOM, few studies have been conducted on how climate change may affect the soil microbial community and, furthermore, on how possible climate-change induced alterations in the ecology of microbial communities may affect soil CO2 emissions. Here we present the results of a seasonal study on soil microbial community structure, SOM decomposition and its temperature sensitivity in two representative Mediterranean ecosystems where precipitation/throughfall exclusion has taken place during the last 10 years. Bacterial and fungal diversity was estimated using the terminal restriction fragment length polymorphism technique. Our results show that fungal diversity was less sensitive to seasonal changes in moisture, temperature and plant activity than bacterial diversity. On the other hand, fungal communities showed the ability to dynamically adapt throughout the seasons. Fungi also coped better with the 10 years of precipitation/throughfall exclusion compared with bacteria. The high resistance of fungal diversity to changes with respect to bacteria may open the controversy as to whether future 'drier conditions' for Mediterranean regions might favor fungal dominated microbial communities. Finally, our results indicate that the fungal community exerted a strong influence over the temporal and spatial variability of SOM decomposition and its sensitivity to temperature. The results, therefore, highlight the important role of fungi in the decomposition of terrestrial SOM, especially under the harsh environmental conditions of Mediterranean ecosystems, for which models predict even drier conditions in the future. © 2010 Blackwell Publishing Ltd.

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