(Luận văn) soil erosion modeling using geographical information system research study in binh gia district, lang son province

THAI NGUYEN UNIVERSITY UNIVERSITY OF AGRICULTURE AND FORESTRY lu an va n JOSE ALBERTO UMALI DUNCA gh tn to p ie SOIL EROSION MODELING USING GEOGRAPHICAL INFORMATION SYSTEM: RESEARCH STUDY IN BINH GIA DISTRICT, LANG SON PROVINCE d oa nl w oi lm ul nf va an lu BACHELOR THESIS z at nh Study Mode: Full-time Major: Environmental Science and Management z m co l gm @ Batch: 2012-2016 an Lu n va Thai Nguyen, 2016 ac th i si Thai Nguyen University of Agriculture and Forestry Degree program Bachelor of Environmental Science and Management Full name Jose Alberto Umali Dunca Student ID DTN1353110554 Soil Erosion Modeling Using Geographical Information Thesis title System: Research Study In Binh Gia District, Lang Son lu Province an MSC NGUYEN VAN HIEU n va Supervisor gh tn to Supervisor Signature Abstract: Land area is one major component in the progress of the p ie w world’s biophysical resources Nowadays, soil erosion is an emerging topic oa nl regarding in the land’s degradation Erosion whether by the subjects’ water, d wind, or tillage; involves three (3) diverse actions – soil detachment, lu va an movement and deposition Soil erosion is not just an ecological issue in human life and property oi lm ul nf Vietnam in general; additionally flash flooding is a significant danger to z at nh Binh Gia District is located75 kilometers far from the capital city of the province which is Lang Son City It is located in the tropical monsoon z gm @ climate, influenced by the general climate of the north; the climate is humid season is 212 mm per month m co l tropical monsoon Average annual rainfall is 1,540 mm, and during the rainy an Lu RUSLE is an erosion model designed average soil losses from sheet and n va rill erosion under specified condition and was developed by Wischmeier and ac th ii si Smith in 1978 However, there are significant limitations due the model only estimates rill and inter-rill erosion, this means that no wind erosion was taken in consideration for the simulation.By the used of GIS technology, this method was adapted by the researcher in conducting a case study in Binh Gia District to model soil erosion The result of the analysis showed that the amount of soil loss in the research area ranges from to 5893.09t/ha/year Furthermore the total soil loss in the area was about 80169 ton per year from 11.1 thousand lu an hectare va n Soil Erosion, RUSLE Method, Geographical tn to Keywords Information System (GIS) gh 59 p ie Number of pages Date of submission d oa nl w oi lm ul nf va an lu z at nh z m co l gm @ an Lu n va ac th iii si Acknowledgements First of all I want to express my sincerest gratitude to my Research Adviser MSc Nguyen Van Hieu to this support to my Bachelor’s Thesis, as well as for his patience, motivation, and great knowledge His guidance has helped me from the beginning, from learning at first, and all throughout my research and for the writing of this thesis as well My special thanks also to his assistants for their support to the lu completion of my paper an n va Deepest thanks to Laguna State Polytechnic University Siniloan Campus, Nguyen University of Agriculture and Forestry to their acceptance to study full-time in p ie gh tn to Siniloan, Laguna to their recommendation to us to study abroad, and also to Thai w their University with a 100% scholarship oa nl Sincere thanks also to Nguyen Vu Tuan Anh, Jimlea Nadezhda Mendoza, d Keraia Vince Geronimo, and Paul Ezekiel Losaria for always around to help, and share lu va an their knowledge for me to finish my study oi lm ul nf Last but not the least, I want to thank God for everything he gave to us; for my family, my aunt and uncle, grandma and grandpa for their love, supports and their this is for you z at nh challenges for me to study hard and be a better student than before And for my Dad, z l gm @ Thai Nguyen, 2016 m co Student an Lu Jose Alberto Umali Dunca n va ac th iv si Table of Contents Table of Contents v LIST OF FIGURES LIST OF TABLES LIST OF ABBREVIATION PART I INTRODUCTION lu an 1.1 Background and rationale n va 1.3 The requirement p ie gh tn to 1.2 Research objective w 1.4 The significance d oa nl PART II.LITERATURE REVIEW an lu 2.1 Theoretical basis nf va 2.1.1 Soil Erosion oi lm ul 2.1.2 Geographical Information System (GIS) 13 2.2 Practical Basis 14 z at nh PART III.METHODS 26 z gm @ 3.1 Materials 26 m co l 3.2 The content 26 3.3 Methods 26 an Lu 3.3.1 Collecting and selecting data 26 n va 3.3.2 Inherited method 26 ac th v si 3.4 The Revised Universal Soil Loss Equation (RUSLE) 27 3.4.1 R factor (rainfall erosivity) 29 3.4.2 K Factor (soil erodibility) 29 3.4.3 LS Factor (Slope Steepness and Slope Length) 32 3.4.4 Factor C (Crop Management) 34 3.4.5 P Factor (Management Practice) 35 PART IV.RESULTS 37 lu an 4.1 The natural conditions and socioeconomic in research area (Binh Gia va n District) 37 tn to 4.1.1 Area’s Climate and weather 38 p ie gh 4.1.2 Digital Elevation Model Map of Binh Gia District 38 4.1.3 Water Resources 39 nl w d oa 3.1.4 Forest resources 39 4.1.5 Mineral Resources 40 an lu 4.1.6 Human 41 nf va oi lm ul 4.2 Result of soil erosion map 42 4.2.1 Rainfall Erosivity Factor (R) 42 z at nh 4.2.2 Soil Erodibility Factor (K) 43 4.2.3 Slope length and Slope steepness factor (LS) 44 z gm @ 4.2.4 Crop Management (C) 48 l 4.2.5 Erosion Management Practice Factor (P) 50 m co 4.2.6 Map editor (In ArcGIS 10.2 Software) 54 an Lu PART V DISCUSSION AND CONCLUSION 57 n va PART VI.REFERENCES 59 ac th vi si LIST OF FIGURES Figure 3.1 Diagrams of RUSLE Method Figure 3.2 Diagrams of Calculating LS Factor Figure 4.1 Binh Gia District Map Figure 4.2 DEM of Binh Gia District Figure 4.3 Rainfall Erosivity Map (Factor R) lu Figure 4.4 Soil Erodibility Map (Factor K) an n va Figure 4.5 Slope Map of Binh Gia District Figure 4.7 Flow Directions and Accumulation ie gh tn to Figure 4.6 Slope Steepness (Factor S) p Figure 4.8 Factor M and F oa nl w Figure 4.9 Slope Lengths (Factor L) d Figure 4.10 Topographic Map (Factor LS) lu va an Figure 4.11 Normalized Difference Vegetation Index Map ul nf Figure 4.12 Crop Management Map (Factor C) Figure 4.15 Date Frame Tool Figure 4.18 Edited Soil Erosion Map of Binh Gia District m co l gm @ Figure 4.17 Other map elements z Figure 4.16 Map Locator z at nh Figure 4.14 Soil erosion chart oi lm Figure 4.13 Soil Loss Map of Binh Gia an Lu n va ac th si LIST OF TABLES Table 3.1 K Factor Value in Northern Part of Vietnam Table 3.2 Coefficient of Vegetation in Vietnam Table 4.1 Soil Erosion Value in every commune lu an n va p ie gh tn to d oa nl w oi lm ul nf va an lu z at nh z m co l gm @ an Lu n va ac th si LIST OF ABBREVIATION ADB: Asian Development Bank DBMS: Database Management System DEM: Digital Elevation Model ESRI: Environmental Systems Research Institute ETM: Enhanced Thematic Mapper FAO: Food And Agriculture Organization lu an GIS: Geographical Information System va n IDW: Inverse Distance Weighted gh tn to MNF: Minimum Noise Fraction p ie MSEC: Management Of Soil Erosion Consortium NDVI: Normalized Difference Vegetation Index nl w d oa PLER: Predict And Localize Erosion And Runoff SLR: Soil Loss Ratio nf va an lu RUSLE: Revised Universal Soil Loss Equation oi lm ul SMA: Spectral Mixture Analysis SWAT: Soil And Water Assessment Tools z USLE: Universal Soil Loss Equation z at nh TIN: Triangulated Irregular Network m co l gm WCP: World Climate Programme @ USPED: Unit Stream Power Erosion/Deposition an Lu n va ac th si PART I INTRODUCTION 1.1 Background and rationale Land area is to be deliberated as the one important geographic sector in the progress advancement of the world's biophysical assets (Bakimchandra, 2011) Impacts of soil erosion picking up the danger of lessening area accessibility and crisp lu water accessible per capita, in this way, nourishment security and manageable an advancement are vital issues in the low accessible area per capita nations (Dercon et va n al., 2012), for example, in Vietnam The essential reason of soil erosion are ecological ie gh tn to debasement, for example, deforestation, heightened land use, and the expanding scene p populace (Ahmed et al., 2010), atmosphere and morphological conditions, for nl w occurrence high concentrated precipitation, steep hill slopes Sometime ago in tropical d oa locales, the top soil layer was regularly ensured by thick vegetation spread, root an lu frameworks (Kefi et al., 2011) ul nf va Soil erosion is not just an ecological issue in Vietnam in general; additionally oi lm flash flooding is a significant danger to human life and property Flash floods are characterized as remarkable floods delivered by extreme precipitation, over rapidly z at nh reacting of catchments and happen inside six hours of the causal precipitation z occurrences gm @ Binh Gia District is located in the hilly and mountainous part of Lang Son l m co Province Binh Gia’s population is 53 214 and covering land area of 1,091 km2 Binh Gia district is fragmented by rocky hills that have a slope of 25-300 or more The an Lu valley is narrow that annual crops are not much, leading to low revenue It is located in va n the tropical monsoon climate, influenced by the general climate of the north; the ac th si lu an n va tn to p ie gh Figure 4.9.Slope Length (Factor L) d oa nl w oi lm ul nf va an lu z at nh z m co l gm @ an Lu Figure 4.10.Topographic Map of Binh Gia District n va ac th 47 si Topographic factor LS was represented by a more complex layer The slope steepness was very much affected by how the chosen the grid cell dimensions in the DEM Wu (2005) stated that the estimation of soil loss by empirical models decreases significantly when the grid cell size is increased This was mainly due to the reduction in general slope steepness The next step in the calibration was therefore mainly focused on determining the right conditions for the LS-factor layer in terms of the grid cell resolution In order to calibrate the model it was executed lu an using a 10, 15, 20, 25, 30, 40 and 50 meter grid cell size n va p ie gh tn to 4.2.4 Crop Management (C) d oa nl w oi lm ul nf va an lu z at nh z l gm @ m co Figure 4.11.Normal Difference Vegetation Index Map of Binh Gia an Lu To calculate the Normal Difference Vegetation Index (NDVI) the researcher followed the formula using the landsat images: “(band5-band4)/(band5+band4)” n va ac th 48 si lu an n va gh tn to p ie Figure 4.12.Crop Management Map (Factor C) of Binh Gia w oa nl After Calculating the NDVI of the research area next step is calculating the C factor d which resulted in the picture above va an lu The C-factor is based on the concept of a standard deviation, in this case an area ul nf oi lm under clean-tilled continuous-fallow conditions The Soil Loss Ratio (SLR) is then an estimate of the ratio of soil loss under actual conditions to losses experienced under the z at nh reference conditions "C" represents the effects of plants, soil cover, soil biomass, and z gm @ soil disturbing activities on erosion RUSLE uses a sub factor method to compute soil loss ratios, which are the ratios at any given time in a cover management sequence to l m co soil loss from the unit plot Soil loss ratios vary with time as canopy, ground cover, an Lu roughness, soil biomass and consolidation change A "C" factor value is an average soil loss ratio weighted according to the distribution of R during the year The sub va n factors used to compute a soil loss ratio values are canopy, surface cover, surface ac th 49 si roughness, prior land use and antecedent soil moisture If a C factor of 0.15 represents the specified cropping management system, it signifies that the erosion will be reduced to 15 percent of the amount that would have occurred under continuous fallow conditions 4.2.5 Erosion Management Practice Factor (P) The erosion management practice, P value, is also one factor that governs the soil lu erosion rate The P-value ranges from 0-1 depending on the soil management activities an n va employed in the specific plot of land In this case the researcher used p = Using the following formula: ie gh tn to Modeling the soil erosion map p A = R K LS C P d oa nl w Using Raster Calculator tool oi lm ul nf va an lu z at nh z m co l gm @ an Lu n va ac th 50 si lu an n va p ie gh tn to d oa nl w oi lm ul nf va an lu z at nh Figure 4.13.Soil Loss Map of Binh Gia z m co l gm @ an Lu n va ac th 51 si Table 4.1.Soil Erosion Value in every commune Communes lu an n va p ie gh tn to d oa nl w Total 15.6 44.6 102 162.2 153 8.5 26 57.8 120.2 76.3 23.1 13 142.6 36.2 21.3 26.2 66 81.3 127.2 45.3 34.3 57.2 34.5 38.1 526 1035 1928.8 807.7 1036.8 395.7 647.2 1512.7 692.5 1324.8 1176.7 1150.8 643.4 1579.7 1056.2 1458.9 429.3 858.2 1500 1925.7 2722.4 6171.4 1911.1 3676.1 2123.1 2290.5 3546.7 1798 3501.7 4612.5 2899.1 1732.5 4243.1 2702.9 4810.9 1544.2 2483.1 4516.3 2460.2 3783.4 8158 2839 4789.2 2541.9 2950.7 5202 2526.7 4847.8 5815.4 4115.9 2457.2 5950 3804.4 6304.1 2030.7 3375.8 6054.4 899.5 1489.5 3140.6 1185.4 2409.3 1288.2 1001.2 1312.5 900.9 991.1 2438.1 1815.9 1439.6 2411.8 1687.2 2196.1 965 1562.1 1726.3 3359.7 5272.9 11298.6 4024.4 7198.5 3830.1 3951.9 6514.5 3427.6 5838.9 8253.5 5931.8 3896.8 8361.8 5491.6 8500.2 2995.7 4937.9 7780.7 59313.3 80169 31013.3 111182.3 lu Strong Moderate Weak Total Area (ha) 315.2 No Erosion (ha) Total Area (ha) oi lm ul nf va an Binh Gia (Townlet) Binh La Hoa Binh Hoa Tham Hoang Van Thu Hong Phong Hong Thai Hung Dao Minh Khai Mong An Quang Trung Quy Hoa Tan Hoa Tan Van Thien Hoa Thien Long Thien Thuat To Hieu Vinh Yen Yen Lo Soil Erosion (ha) 1050.7 19805 z at nh Value of (T/ha/year) (Ministry of Natural Resources and Environment, 2012.Circular z land degradation) n va Strong Erosion: ≥ 50 an Lu Moderate Erosion: ≥ 10 - 50 m co Weak Erosion: < 10 l No erosion: gm @ 14/2012 / TT - BTNMT on Administrative Rules Committee investigation techniques ac th 52 si Soil Erosion 1% 18% 28% lu an n va 53% tn to Strong Moderate Weak No Erosion ie gh p Figure 4.14.Soil Erosion Chart oa nl w Based on the result after processing the data using ArcGIS 10.2, it shows that the amount of soil loss in Binh Gia District was about 80169 ton per year from 11.1 d lu va an thousand hectare The size of the research area is 111182.3 Binh Gia district’s 31013.3 of land area have no erosion Hoa Tam and Quy Hoa are the communes ul nf oi lm that are not having a great number of soil erosion Minh Khai commune is the largest area having strong erosion, measuring of 142.6 followed by Thien Hoa commune z at nh then Hoang Van Thu The total area having strong erosion in the research area is z gm @ 1050.7 ha, only 1% of the total land area 18% of the total area of Binh Gia District is affected by moderate erosion Binh Gia townlet, Hong Tai and To Hieu communes l m co have the least number of moderate losses of soil Around a half of the land area of an Lu Binh Gia district have weak soil erosion with the total of 59313.3 Most of the communes have much number of it compare to the area having strong, moderate and n va no erosion ac th 53 si The spatial areas of the high spot range for soil disintegration in the study uncovered that the potential soil misfortune is regularly more prominent along the more extreme incline banks of tributaries Other high soil disintegration ranges scattered all through the bowl and is ordinarily connected with high disintegration potential area employments The plain range of the bowl demonstrates the slightest defenseless against soil disintegration lu an va n 4.2.6 Map editor (In ArcGIS 10.2 Software) ie gh tn to Creating a new page layout p The first step in ArcMap was changing the map view to layout d oa nl w nf va an lu oi lm ul Figure 4.15.Data frame tool Adding a data frame to the page layout z at nh The data frame displays a collection of layers drawn in a particular order for z a given map extent and map projection Adding a data frame to the page layout using l gm @ the Insert menu From this menu, insert additional data frames These additional data frames for m co locator or detail maps If using multiple data frames, may want to consider using extent an Lu indicators to show the extent of one data frame within another data frame A good locator va map will also contain an indicator, such as an outline, showing where the extent of the n ac th 54 si detail map fits within a larger extent For example, the locator map might show the location of a state within a country lu an va n Figure 4.16.Map Locator gh tn to Adding other map elements to the page layout p ie Using the Insert menu to select other map elements to add to layout Using this menu to add a title to the page The added text will be the same as the text nl w d oa entered for the title in the Map Document Properties dialog box Along with a title, oi lm ul nf va an lu it’s can be add (static) Text and Dynamic Text z at nh z gm @ Figure 4.17.Other map elements m co l an Lu Printing and exporting layout n va ac th 55 si After completed this work on the layout, printing the map or create other types of output formats—PDF files, PostScript files, or Illustrator files Under the file menu, using options to open the Page and Print Setup dialog box, Print Preview, Print the page, or to Export Map lu an n va p ie gh tn to d oa nl w oi lm ul nf va an lu z at nh z m co l gm @ an Lu Figure 4.18.Edited Soil Erosion Model Map of Binh Gia District n va ac th 56 si PART V DISCUSSION AND CONCLUSION The goal of the study was to assess the capital distribution of soil loss in Binh Gia District, Lang Son Province By the used of ARCGIS 10.2 software the researcher modeled soil loss map of the research area After applying RUSLE method in modeling soil erosion map of Binh Gia District, the researcher found that the research lu an area was not greatly affected by soil erosion, only in Southwest part where the n va vegetation was on moderate level RUSLE method has limitation and it is clearly means that no wind erosion is taken in consideration for the simulation p ie gh tn to stated on the definition that the model only estimates rill and inter-rill erosion This w Application of RUSLE method using ARCGIS 10.2 software serves as a useful oa nl tool for soil erosion modeling in a large scale However, there are significant d boundaries of remotely sensed data due to coarse resolution and geometric distortions lu va an that constrains the accuracy of erosion modeling In spite of the fact that, dirt oi lm ul nf disintegration hazard displaying suits a few shortcomings, disintegration hazard maps will help ecological and normal assets administration offices screen the status of z at nh disintegration and influenced components to soil Soil Erosion, for example, land spread, land use, and topographic elements, z gm @ overlaying disintegration hazard maps and slant limit maps empower land supervisors m co l and strategy producers to at first recognize areas and territories of assurance backwoods which can diminish soil disintegration and enhance environment quality an Lu Moreover, it is conceivable to incorporate remotely detected information and the n va RUSLE inside GIS stages as a screening apparatus when settling on choices on ac th 57 si selecting fitting area use situations Be that as it may, reenacted disintegration dangers ought to be reviewed and accepted with genuine information Land supervisors and strategy producers ought to lead soil disintegration hazard appraisal for upland zones in the area use arranging Fusing additionally supporting information, for example, nearby learning, financial states of neighborhood family units, approach, and others, to assemble a multi-criteria or multi-operators model - based woodland land arranging lu an n va p ie gh tn to d oa nl w oi lm ul nf va an lu z at nh z m co l gm @ an Lu n va ac th 58 si PART VI.REFERENCES Ahmed M Y, Biswajeet P, & Abdallah M H (2010) Flash flood risk estimation along the St Katherine road, southern Sinai, Egypt using GIS 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