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The medium-scale spatial patterns of soil seed banks (SSBs) and extant vegetation and the roles of abiotic factors are poorly understood. We selected the dry Minjiang River valley of southwest China to investigate SSB structure and corresponding extant vegetation in a medium-scale size (200-230 km long, 3-4 km wide) at eight sites across the valley using a germination method and field surveys. We found that, there was low seed density and species number in SSB and less coverage and litter thickness for community in extant vegetation at central sites compared with transitional sites across the dry valley; Quercus spp. occurred frequently in extant vegetation at transitional sites, while Caryopteris spp., Jasminum spp., Rabdosia parvifolia. Sophora davidii, Campylotropis spp., and Bauhinia faberi var. Microphylla was present frequently at central sites: Carex spp. and Artemisia spp. occurred frequently in SSB at transitional sites, while Ajania spp., Poa spp., and Fagopyrum caudatum was present more frequently at central sites. Hierarchical cluster analysis and Kendall’s correlation showed that the spatial variation of both SSB and extant vegetation had significant correlation with rainfall and air evaporation. Crown Copyright (C) 2011 Published by Elsevier Ltd. All rights reserved.