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Accueil du site → Master → Chine → 2017 → Effect of Trampling Disturbance on Infiltration of Biological Soil Crust in the Hilly Loess Plateau Region,China

Northwest A&F University (2017)

Effect of Trampling Disturbance on Infiltration of Biological Soil Crust in the Hilly Loess Plateau Region,China

石亚芳;

Titre : Effect of Trampling Disturbance on Infiltration of Biological Soil Crust in the Hilly Loess Plateau Region,China

Auteur : 石亚芳;

Grade : Master’s Theses 2017

Université : Northwest A&F University

Résumé partiel
Biological soil crust(biocrusts)extensively developed in the Hilly Loess Plateau region after the“Grain for Green” eco-project was implemented in the region,with an average coverage of 60%-70%.Biocrusts played an important role in the soil hydrological cycle,affecting the process of water infiltration.Disturbance was a common natural phenomenon,and biocrusts were very sensitive to the varieties of natural and human disturbance.In this paper,aimed to determination of different disturbance intensities on the biocrusts community composition,soil physical and chemical properties and soil infiltration,simulated rainfall trails,linear run-on method and infiltration test and natural rainfall monitoring test were used in the typical Hilly Loess Plateau,combined with indoor analysis.The influence of the disturbance on the biocrustal soil infiltration was revealed by the mathematical statistics analysis,which provided the scientific basis for the ecological restoration construction and the scientific management of the cultivated land in the Hilly Loess Plateau.The results are as follows :(1)Disturbance could significantly affect the coverage and composition of biocrusts.The degree of impact was related to the disturbance intensities.Disturbance significantly reduced the coverage of biocrusts,increased the coverage of the bare soil,which was related to the disturbance intensities.The disturbance significantly reduced the biomass of cyanobacteria and moss,which was related to the intensities of disturbance.The biomass of cyanobacteria and moss decreased linearly with the increase of disturbance intensities.In the biocrustal soil box,compared with the undisturbed treament,20%-50% disturbance decreased by 7.7%,15.0%,14.8% and 32.8%,respectively.The reduction of moss coverage was 5.2%,7.2%,11.7% and 8.3%.The increase of bare soil coverage was 8.7%,17.4%,30.9% and 35.8% respectively.In the field scale,the biocrusts coverage of 9%-30% disturbance decreased by 7.7%,14.2%,23.4%,18.5% and 5.7% than that of the background.The cyanobacteria coverage of undisturbed reduced by 1.6% that of background.And the cyanobacteria coverage of 9%-20% disturbance decreased respectively 2.5%,9.6%,13.7%,5.5% than the background.The cyanobacteria coverage at 30% disturbance was increased by 0.7% than that of the background.And the moss coverage of 9%-30% disturbance decreased respectively 13.9%,6.8%,5.5%,7.4%,12.1% and 5.6% than the background.Coverage of cyanobacteria and bare soil under 9% and 14% disturbance increased by 3.5% and 9.4%,respectively,compared with the background.The difference was not significant.The coverage of disturbed and bare soil coverage at 17% and 30% disturbance increased significantly by 12.1%,14.3% and 23.3%,respectively than that of the background..The cyanobacteria biomass at 9%-30% disturbance decreased by 8.1%,21.1,28.4 %,37.8% and 38.3%,respectively than that of the background.And the moss biomass decreased by 67.1%,55.1%,55.1%,65.7% and 92.7% respectively than that of the background.(2)Disturbance significantly affected the biocrustal soil physical and chemical properties,and the degree of influence was related to the disturbance intensities and soil depth.Disturbance reduced the content of soil organic matter in the biocrusts and increased the surface roughness of the biocrusts.Disturbance had no significant effect on the physical and chemical properties in 0-2 cm soil layer.The content of soil organic matter in the biocrustal soil was decreased by 5.5%,24.6%,3.6%,4.4% and 3.3%,respectively than that of background.The change of organic matter in the biocrustal layer at the treatment of 14% disturbance was significantly lower than that of the background.The change of organic matter of other treatments decreased than that undisturbed treatment,but the difference was not significant.After one year,the content of organic matter in 0-2cm soil layer decreased with the disturbance of different intensities,and the changes of different treatments were not significant.Compared with the background,the bulk density at 9%-30% disturbance was increased by 6.6%,6.2%,5.7%,8.3% and 8.7%,respectively.The porosity of biocrustal soil was lower than that background.Compared with the background,the porosity at 9%-30% disturbance was decreased by 4.2%,4.1%,3.8%,5.0% and 5.3% respectively.T

Mots clés : biological soil crusts; tramping disturbance; community composition; infiltration; linear run-on method;

Présentation (CNKI)

Page publiée le 19 janvier 2018