三峡库区农林复合系统根系分布及分形研究

通过对柑桔×小麦+金乔麦植物篱、柑桔×小麦+茶树植物篱、柑桔×小麦+银合欢植物篱等系统的组成植物材料不同径级根系垂直分布、水平分布和系统的根系分布及竞争,以及柑桔、银合欢的根片段分形研究表明:植物材料根系呈典型的Gauss曲线分布,少数呈Lorentz分布;柑桔×小麦+茶树植物篱复合系统根系存在着较强的竞争关系,与柑桔×小麦+金乔麦植物篱复合系统相比,小麦减产18.5%,柑桔单果平均重减小14.3%;柑桔和银合欢的大部分分形参数与林龄或Ln-1间存在着3/4的标度关系,分形研究将丰富农林复合系统的结构优化方法,提高科学性、可操作性、可预见性。

Study on Root Distribution and Fractional Structure of Agro-forestry Systems in Three Gorges Reservoir Region

By inspecting and analyzing on vertical,horizontal distribution and competition of roots in Citrus intercropping wheat and planting Fagopyrum Mill as hedgerows,Citrus intercropping wheat and planting Camellia sinensis CL O.kuntze as hedgerows,Citrus intercropping wheat and planting Leucaena glauca as hedgerows etc agro-forestry systems,and fractional structure discipline of Citrus and Leucaena glauca,this research displays that root vertical and horizontal distribution curves obey typical Gauss curve and Lorentz curve;in comparison with Citrus intercropping wheat and planting Fagopyrum Mill as hedgerows,roots in agro-forestry system of Citrus intercropping wheat and planting Camellia sinensis CL O.kuntze as hedgerows have stronger competitive relation,reduction of output of wheat reaches 18.5 percent,average weight of Citrus decreases 14.3 percent;some fractional parameters of Citrus and Leucaena glauca have relation with 3/4 square of age of forest or L_(n-1).Studying on fractional branching principle will enrich optimizing methods on structure of agro-forestry systems,enhances its scientificness,maneuverability and foreseeable capacity.