Study On Ecological Benefit Of Artificial Bush Dune-Fixing Forest In Yulin Sand Land

Based on theories of landscape ecology,systems engineering and sustainable development,according to combing standard plot investigation and permanent plot observation,single technology and corresponding technology,located observation and experimental analysis,mathematical methods and computer technology,the paper researched on the ecological function of fixing sand forest in Yulin sandy land,established the synthesis ecological benefit evaluating indicator system,evaluated the comprehensive ecology function of windproof solid sand scrub forest's.That provided the theory instruction for the artificial vegetation construction and the region ecological environment improvement of Yulin desert region.The main conclusions show as following:(1) The bush dune-fixing forest increased the surface roughness,weakened the surface layer wind speed,and reduced the surface load,played the windproof solid sand role.(2) In the solid sand bush,the soil physics and chemistry nature were changed,the soil structure was improved,and the soil fertility was enhanced.The soil clay was increased 2～2.75 times,meanwhile the organic matter increased 2～20 times,the entire N increased 3～22 times,the fast-acting P increased 10%～160%.(3) The solar energy use efficiency of the solid sand bush energy was low extremely,it had 0.02%～0.05%equally,and thus the biomass of dune-fixing forest was low.The biomass in lands between dunes was high relatively by in foredune.The difference of biomass between both sites reached to 33%～162%.(4) The comprehensive ecological benefit of the primary five sand-fixed shrubs was evaluated,the result order is Hedysarunlaeve(40.81)>Amorpha fruticasaL(39.13)> Caragana korshinskii(37.43)>Salix psammophila(37.31)>H.scoparium(35.19) by the evaluate score.In the windward slope of the sand Hedysarunlaeve is the best,Taking mixed forest can increase structural the stability and improve the eco-benefit.