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چکیده
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Investigating of seed bank and seed dispersal mapping of weeds in different ecosystems is necessary. Comparing these two, can provide a long-term weed management and also predict the existence of specific weeds. Therefore, this study was carried out in autumn 2011 in farmland, orchards and pastures at Saqqez city, Kurdistan province, Iran to evaluate seed dominance of different species in different ecosystems. Different crop rotations were randomly selected around the town (approximately 20 km distance from each other). There were 5 different rotations included two continuous cultivation of wheat (dry and irrigated; ww), wheat – sugar beet (ws), wheat – peas (wp), pasture (p) and orchard (o). Seed bank sampling was a systematic w pattern which was done in three depths (0 - 5, 5 - 15 and 15 - 25 cm). Then seeds from these samples were isolated and identified. Different soils in this study were contained 114 plant species from 24 plant families. Results showed that Eragrostis cilianensis (All.) Vign., Roemeria refracta DC. were the common species among all ecosystems. Disturbance factor seems to have no effect on the mentioned species as they can survive in all ecological conditions. No rotation, but pasture affected Amaranthus chlorostachys auct. and produce different proportions. Amaranthus had the most frequency in ws (50%) and Salsola ruthenica L. only found in wp rotation and was more common in disturbed dry lands. Also, Sinapis arvensis L. and Vaccaria oxydonta Boiss. had the highest frequency in wp rotation. Dicot species of Galium tricornutum Dandy, Lamium amplexicaule L., Portulaca oleracea L., and Avena ludoviciana Durieu had notable abundance in the irrigated monoculture wheat fields as the common method of weed control was 2,4-D application which did not affect them. There were a dominance and diverse composition seed bank of annual broadleaf, winter grasses and perennials species (Lactuca serriola L., Avena ludoviciana Durieu, Setaria viridis L. and Cynod
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