Dissertation > Excellent graduate degree dissertation topics show

An Applied Research of Small Watershed Soil Erosion Model in the Loess Plateau

Author: QinLing
Tutor: QinFen
School: Henan University
Course: Cartography and Geographic Information Systems
Keywords: Chabagou watershed annual empirical model distributed precipitation model soil erosionmathematics model system applicability
CLC: S157.1
Type: Master's thesis
Year: 2013
Downloads: 0
Quote: 0
Read: Download Dissertation

Abstract


For a long time, the Loess Plateau is one of the worst areas suffering soil erosion in theworld, especially the sandy area in the Yellow River Basin. Long-time soil erosion has causedexiguous vegetations, worsening environment and weak co-logical environment. Abundantsoil erosion has easily led to sediment deposition of stream channels in the lower area andraised many problems like floods. Therefore, the highpoint of scholars’ research subjects fromhome and abroad is building a model of soil erosion applicable to this area and using such amodel to simulate erosion and sediment, make a forecast about the soil erosion in the LoessPlateau, provide scientific evidences and to make improvement on regional ecologicalenvironment. It also becomes a pressing task for governing the Yellow River.Chabagou watershed is situated in the sandy area where waterfall and geographicfeatures are typical. Therefore the study on the adaptability of different erosion and sedimentyield model will be of great importance to the productive practice and the research on erosionand sediment in sandy areas. The thesis chooses different types of erosion models （empiricalmodel of watershed scale and distributed mechanism model） and compares watershedapplicability of different models and model applicability of different geomorphic unit with theaid of GIS and remote sensing technique. On one hand, the thesis analyzes the geomorphicunit of high sediment yield in order to take specific measures on protection and management;On the other hand, by extending the range of models application, the thesis aims at making amodel transplantation. The main research content and results of the thesis are as follows:（1）Choose two systems of high accuracy with different erosion mechanism model bycomparing the advantages, disadvantages and application of different models based on theconditions of the soil erosion model of Chabagou watershed. Analyze the two mechanism andmake improvement on the model systems.（2）Use two models to calculate the erosion and sediment yield under the mathematicalmodel system of soil loss in loess plateau. The results show that both the two models havehigh simulation accuracy. The higher the simulation accuracy, the more applicable to thecalculation of watershed annual sediment yield.（3）Analyze the erosion and sediment yield contribution in different soil via ArcGIS,among which open forest and moderate covering grassland have a sharp inhibition to erosionand sediment yield. The contribution of slope farmland is comparatively big and it suffers aserious sand loss. The two different models both have high accuracy on sediment yield modelin different soil and can be used in sand yield calculation.（4）Pick up the erosion unit of the Liangang slope, gully slope and ditch based on theDEM data. When the slope of the gully slope is within25o~45o, soil erosion can easily emergewith a biggest contribution. Compared with annual empirical model, precipitation mechanismmodel is applicable to the sediment yield calculation of gully slope unit. When used inLiangang slope unit and and ditch unit, both of the two models have high accuracy and can beused in its calculation of yield unit.（5）Heavy rain in Chabagou watershed is mainly in July, August and September, whenthe sand yield is fourth times larger than that in other months. It is of great importance to study the applicability model in heavy rains. Through comparative analysis it turns out thatprecipitation mechanism model has a higher accuracy than annual empirical model and ismore applicable to analog computation of sediment yield in heavy rains.By comparing the two different models, the thesis comes up with a result that Chabagouwatershed is the most suitable soil erosion model for sediment yield simulation and enlargesthe application range of the two models. The thesis also provides a certain help for themanagement of soil erosion in sandy area in the Yellow River Basin and make a guidance tothe study of erosion and yield in similar landscapes.

Related Dissertations

  1. Japanese Language Proficiency Test ( 2 ) Full ni concise analyzes on the applicability of materials,H36
  2. The room sell \,D923.2
  3. Evaluation Research on Applicability of Broadbanding,F224
  4. Study on the Influencing Factors of Building Life,TU201
  5. Research on the Applicability of the CC-LM in the Less-Developed Regions in China,F822.0
  6. Study of Dynamic Equivalent of Power System Based on Parameter Identification,TM712
  7. Microblogging spread within the enterprise Applicability,F272
  8. Asphalt Pavement Preventive Maintenance Decision Support System,U418.6
  9. Capital Asset Pricing Model in Shanghai Stock Market Analysis,F832.51
  10. Applicability Evaluation About Several Typical Physical and Chemical Pretreatment Technologies for Landfill Leachate,X703
  11. An Analysis on Application of Anti-Trust Law in the Insurance Industry of China,D922.294
  12. Criminal fine study,D924.1
  13. The Mode of Operation Research about Increase and Decrease of Urban and Rural Construction,F301
  14. Research on the Management for E-government Geographical Information Service Application Model,P208
  15. Study on Public Space Design of Urban Residence Community in NanChang Affordable Husing,TU984.12
  16. Analysis of Applicability of Communicative Distance Theory in Chinese Cultural Context,H0-05
  17. ADR in the applicability of research to resolve environmental disputes in China in,D925
  18. The Design and Implementation of Technical Standard System and Its Management Platform for the Pillar Industries in Liuzhou,F203
  19. Research on Saving Energy and Applicability in Surface Water Source Heat Pump System,TU831.3
  20. The Applicability of Inflation Targeting in China,F822.5
  21. Study on Evaluation of Enterprise Value Based on REVA,F275

CLC: > Agricultural Sciences > Agriculture as the foundation of science > Soil > Soil and Water Conservation > The causes and prevention of soil erosion
© 2012 www.DissertationTopic.Net  Mobile