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In this study, Wuqi County, Shaanxi typical abandoned farmland in the Loess Plateau in northern wind erosion crisscross region as research subjects, different aspect Abandoned Lands different Abandoned years as a research plots of farmland on the number of years were 0 (agricultural land), 2 years, 3 years, 8 years, 9 years, 12 years (samples were selected as a comparative study of slope and sunny slope), 20 years and 30 years of Abandoned plots of ground vegetation conditions and soil seed bank conducted a field survey sampling and indoor germination experiment, through the analysis of the basic characteristics of the soil seed bank, the comparative study of the ground vegetation characteristics, the following results were obtained: (1) the number of the study area, the kind of soil seed bank seed germination time distribution pattern is not with the farmland of years increase in an upward trend, but was increased and then decreased peak change, changes in density values ??between 467.0 ± 34.4 ~ 4283.0 ± 312.2 grains / m2, Abandoned life of 8 and 9 plots of soil seed Gallery maximum density. (2) or more years of different Abandoned plots soil seed bank germination soil experiments, 0 to 5cm soil germination seed density changes in between 367.0 ± 36.0 ~ 2833.0 ± 224.0 grain / m2, 5 ~ 10cm soil layer of changes in soil seed bank density was 100.0 ± 14.9 ~ 1450.0 ± 104.2 Li / m2, 0 to 5cm soil layer of soil seed bank density is 5 ~ 10cm layer of 2 to 3 times. (3) of the study area, the soil seed bank, germination of seed plants dicotyledons majority, the number of its seed germination average of 1,136 / m2 monocotyledon seed germination number 713 / m2, only accounted for seed germination 38.5% of the total. (4) in the aboveground vegetation statistics to 6 families, 15 genera and 25 species of plants, which major plant species the Gramineae (7 species) and Compositae (7 species), legumes (4 species), Rosaceae (5) second; analysis from the life form of plants, the highest proportion of perennial herbaceous plants, the proportion of semi-shrubby plants followed a biennial herb lowest proportion. Farmland in the study area, the soil seed bank Artemisia gmelinii, some of the early successional species up to call inside Lespedeza, Stipa and Leymus dominated. Soil seed bank and aboveground vegetation had no woody appears, therefore, to speed up the process of vegetation restoration in the study area, should be appropriate to introduce a number of late-successional species to shorten recovery and succession of time, the revegetation process in the region, artificially added Jianqun tree various sources, promote vegetation restoration of the Loess Plateau in northern wind erosion crisscross zone.
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