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Through the establishment of standards, Baise City, Guangxi Hechi City Grain for Green Project octagonal (Illiciumverum), walnut (Juglans regia), chestnut (Castanea mollissima) Masson pine (Pinusmassoniana) southwest birch (Betula alnoides) and eucalyptus (Eucalyptus) The other six kinds of different vegetation restoration patterns understory vegetation. The results are as follows: 1, the total biomass of the tree layer increases with increasing farmland time, site conditions, fertilization or not the initial planting density; species speed by nature, planting density, site conditions affect tree layer each proportion of organ biomass; timber mode shrub and grass biomass by the obvious impact of tree layer canopy density, canopy density, biomass, canopy density, biomass, shrub and grass biomass and economic forest mode by human influence tending tending wide range of large and small biomass Conversely large biomass. Mode of understory plants herbal-based, community structure is simple, the level of differentiation is not obvious, positive herbaceous dominant herbaceous communities, Gramineae, Compositae occupies an important position in the species composition of each mode; shrub layer and herb layer species diversity indices are very small, are below 2.5796; smaller shrubs, herbaceous layer species diversity index as the Abandoned increasing age difference; different Abandoned time, vegetation recovery mode shrub, herbaceous species diversity index no significant differences in the only octagonal vegetation recovery mode herbaceous species diversity index significant differences because tending intensity caused; 2004 farmland southwest birch and pine, southwest birch and walnut, eucalyptus and walnut, Shannon-Wiener index, chestnut and walnut shrub layer there is a very significant difference; eucalyptus and chestnut herb layer species diversity index very significant difference; masson pine and chestnut herb layer Simpson index, there is a very significant difference. 3 Litters thickness between 1-3cm, with increasing farmland time the vegetation recovery mode Litters thickness has increased; dry weight of litter size by the shrub and grass biomass and strength of human tending, shrub and grass large biomass of litter dry weight, and vice versa, human tending the strength of litter dry weight, otherwise small; of of litter absorbent multiples and dry The falling objects constitute, shrub and grass easier decomposition of litter proportion of litter absorbent multiples less decomposition of masson pine, eucalyptus Litters proportion, litter the water absorption multiples In small; dry weight of litter water absorption and litter, litter multiples of water absorption, litter descending order of the amount of water absorption: southwest birch> walnut> eucalyptus> anise> Masson pine> Chestnut.
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