| As a kind of biological groups with special significance in the history of biological evolution,desert algae play an important role in the comprehensive management of desertification.Desert algae crust with wind and sand,to prevent soil erosion,improve soil quality and species of colonization and other aspects of ecological functions.Therefore,in today's increasingly serious desertification,the desert algal crust has a very positive meaning to improve the soil,wind and sand.The technology of artificial desert algal crust is a process of taking a series of m easures to make the desert algae form a layer of biological crust rapidly on the surface of quicksand.In this study,Microcoleus vaginatus as experimental materials,through field sampling combined with indoor experiment,from the following four aspects,such as,the impact of artificial algal crusts on soil physicochemical properties of artificial algal crusts on four kinds of seed germination of desert plants,the effects of artificial algal crusts against surface erosion,the effects of in-situ and crusts on physico chemical properties of desert soil;A preliminary study of artificial algal crust of sand-fixation technique Minqin,Gansu Province semi-desert areas.The experimental results show that:(1)The formation of artificial algae crust,the phy sical and chemical properties of the soil has a significant impact.Compared with CK group,the soil bulk density and p H value showed a decreasing trend,while the soil's maximum water holding capacity,total soil porosity,organic matter,total N,total P content and available N available P and available K content are showing an upward trend.The improvement of soil quality was the greatest in the initial inoculum amount of 10 ?g · cm-2,and the improvement of soil nutrients was most significant in the soi l matrix of the leeward slope in different site conditions.(2)Different artificial algal crusts on the formation of four kinds of seed germination of desert plant effects vary by species,artificial algal crusts have obvious promoting effect on the germination of seeds of three species of Sand rice,seeds of Artemisia arundinacea and red sand,has obvious inhibitory effect on the germination of seeds of the Hedysarum scoparium.The results showed that the seed germination of the three kinds of plant seeds was the highest at the initial inoculation amount of 10 ?g·cm-2 on the top of the slope,the windward slope and the leeward slope.However,in the crust of the soil between sand dunes;the crusts were the highest in the seed germination of the three plant seeds at the initial inoculation amount of 5 ?g·cm-2;the germination rate of Hedysarum scoparium on artificial algae crust was significantly lower than that on quicksand,and decreased with the increase of initial inoculation amount.(3)The formation of artificial algae crust can effectively improve the wind speed of soil particles and reduce the wind erosion intensity of soil.At larger wind speed,the crust of desert algae can obviously improve the aerodynamic roughness length and friction wind speed,there was a positive correlation between dynamic roughness length and friction wind speed with crust damage rate.The wind speed profile of different algae crusts was logarithmically distributed,and the influence of crust on wind speed was mainly in the height of 150 mm.When the crust damage rate is 50%,the crustal aerodynamic roughness length,friction wind speed and wind speed profile change is most obvious.(4)In the wild,the artificial algae crusts had obvious enrichment effect on the soil nutrient,and the nutrient enrichment increased with the increase of crustal age.At the same time,the results showed that in the field in the process of application of crust technology,the initial inoculation amount should be 10 ?g·cm-2 inoculated for the best,and the artificial management and care stage should be the ini tial watering volume of 1000 m L·m-2,watering mode W(evening Watering)is appropriate. |
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