Salinity stress modulates habitat selection in the clonal plant Aeluropus sinensis subjected to crude oil deposition1,2

摘要

DING, W. J. (Institute of Ecology and Biodiversity, School of Life Sciences, Shandong University, Jinan 250100, P. R. China), J. LIU (Institute of Environment Research, Shandong University, Jinan 250100, P. R. China), D. Q. WU, Y. WANG (Institute of Ecology and Biodiversity, School of Life Sciences, Shandong University, Jinan 250100, P. R. China), C. C. CHANG (Department of Civil and Environmental Engineering, University of Maryland, Baltimore County, Maryland, 21250), and R. Q. WANG (Institute of Ecology and Biodiversity, School of Life Sciences, Shandong University, Jinan 250100, P. R. China). Salinity stress modulates habitat selection in the clonal plant Aeluropus sinensis subjected to crude oil deposition. J. Torrey Bot. Soc. 138: 262-271. 2011. - Environmental stresses and disturbances are common in terrestrial ecosystems. Clonal integration and foraging behavior are often, but not always, beneficial for clonal plants grown in heterogeneous stressful environments. In this study, clonal fragments of the clonal perennial herb, Aeluropus sinensis (Debeaux) Tzvel (Poaceae), were grown with stolons connected or severed at five salinity levels (0, 50, 100, 200, and 400 mmol L^sup -1^ NaCl). In each clonal fragment, the apical ramet was exposed to crude oil on the sediment surface while the basal ramet was not. We proposed three possible scenarios: growth of the apical ramet subjected to crude oil would be (1) enhanced, (2) limited, or (3) not affected by clonal integration. Results supported scenario (2). Responses to crude oil differed between plants grown at low and high salinity levels. For A. sinensis, at high salinity levels, clonal integration promoted habitat selection by decreasing biomass of apical parts to escape the oil polluted habitats and increasing clonal growth of basal parts to select the unpolluted habitats, while at low salinity levels, connection did not influence growth of the basal or apical parts. Salinity modulates the behavior of a clonal plant subjected to heterogeneous crude oil contamination, at least in A. sinensis.