caa a22 4500 475751434 CHVBK 20180406123524.0 cr unu---uuuuu 170329e20001001xx s 000 0 eng 10.1023/A:1026541428547 doi (NATIONALLICENCE)springer-10.1023/A:1026541428547 Indirect effects in a desert plant community: is competition among annuals more intense under shrub canopies? [Elektronische Daten] [Katja Tielbörger, Ronen Kadmon] An unresolved discussion in contemporary ecology deals with the relative importance of competition along environmental gradients. In deserts, local-scale differences in environmental productivity may be caused by the presence of shrubs, which represent a favorable habitat for annual populations within a nutrient-poor matrix. In this study, we attempted to test the hypothesis that facilitation of desert annuals by shrubs increase the intensity of competition among the annual plants. Such negative indirect effects have so far been ignored in studies about plant-plant interactions. We tested our hypothesis by measuring seedling survival and fecundity of four abundant annual plant species with and without neighbors in open areas and under shrub canopies in a sandy desert area. Our findings did not indicate indirect negative effects of shrubs on their understory annuals. Sensitivity to the presence of neighbors varied between species and surprisingly, the species with the smallest seeds was the only one which was not negatively affected by the presence of neighbors. In contrast to our hypothesis, there was no difference between the habitat types shrubs and openings in absolute and relative competition intensity. Our overall results suggest that negative indirect effects of shrubs are unimportant in determining demographic response of understory annual plants. Kluwer Academic Publishers, 2000 Annual plants nationallicence Competition nationallicence Desert nationallicence Environmental gradients nationallicence Experiments nationallicence Facilitation nationallicence Indirect interactions nationallicence Sand dunes nationallicence Seed size nationallicence Shrubs nationallicence Tielbörger Katja Institut für Vegetationsökologie und Naturschutz, Universität Potsdam, 14469, Maulbeerallee 2, Potsdam, Germany aut Kadmon Ronen Department of Evolution, Systematics and Ecology, The Hebrew University of Jerusalem, 91904, Jerusalem, Israel aut Plant Ecology Kluwer Academic Publishers 150/1-2(2000-10-01), 53-63 1385-0237 150:1-2<53 2000 150 11258 https://doi.org/10.1023/A:1026541428547 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1023/A:1026541428547 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Tielbörger Katja Institut für Vegetationsökologie und Naturschutz, Universität Potsdam, 14469, Maulbeerallee 2, Potsdam, Germany aut NATIONALLICENCE 700 1- Kadmon Ronen Department of Evolution, Systematics and Ecology, The Hebrew University of Jerusalem, 91904, Jerusalem, Israel aut NATIONALLICENCE 773 0- Plant Ecology Kluwer Academic Publishers 150/1-2(2000-10-01), 53-63 1385-0237 150:1-2<53 2000 150 11258 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer