Runoff generation and soil erosion from different age of acaia plantation forest in truong son commune, luong son district, hoa binh province, viet nam master thesis in forest science

99999999999999999999999999999999999999999999999999999999999999 MINISTRY OF EDUCATION AND TRAINING MINISTRY OF AGRICULTURE AND RURAL DEVELOPMENT 999999999999999999999999999999999999999999999999999999 VIETNAM NATIONAL UNIVERSITY OF FORESTRY  CHIN KOLYAN RUNOFF GENERATION AND SOIL EROSION FROM DIFFERENT AGE OF ACACIA PLANTATION FOREST IN TRUONG SON COMMUNE, LUONG SON DISTRICT, HOA BINH PROVINCE, VIETNAM MASTER THESIS IN FOREST SCIENCE Hanoi, 2018 MINISTRY OF EDUCATION AND TRAINING MINISTRY OF AGRICULTURE AND RURAL DEVELOPMENT VIETNAM NATIONAL UNIVERSITY OF FORESTRY  CHIN KOLYAN RUNOFF GENERATION AND SOIL EROSION FROM DIFFERENT AGE OF ACACIA PLANTATION FOREST IN TRUONG SON COMMUNE, LUONG SON DISTRICT, HOA BINH PROVINCE, VIETNAM Major: Forest Science Code: 8620201 MASTER THESIS IN FOREST SCIENCE Signature: ……………………… Supervisor: Assoc Prof Dr Bui Xuan Dung Hanoi, 2018 ii ABSTRACT Vegetation cover is the key factors that protect the soil, reduce surface runoff and soil erosion Present days, citizens are paying more attention to the industrial plantation in Vietnam, especially Acacia magium plantation as it takes part in improving the socio-economic condition To propose a solution to mitigate the impact of Acacia plantation, understanding about runoff generation and soil erosion are needed To determine the characteristic of runoff generation and soil erosion derived at the different ages of Acacia plantation forest in Luong Son headwater of Vietnam, four plots (15m2) were set up Of those, plots (up-hill and down-hill) in 1-year-old Acacia plantation and plots (up-hill and down-hill) in 5-years-old Acacia plantation The main finding includes: (1) runoff coefficient at Acacia 1year-old down and up was (0.36% - 0.46%) with the average 0.41% And Acacia 5years-old, down and up was (0.35% - 0.39%) with the average 0.37% It shows the slightly different between the locations of two years due to the different ground cover However, t-test result showed that the difference between locations in years one and year-5 are not significant (P-value = 0.31 and P-value = 0.96 respectively) T-test also indicated that there was no significant difference in term of an runoff at two different ages of Acacia plantation with (P-value = 0.95 > 0.05); (2) soil erosion is significantly different between two years of Acacia plantation (P-value = 0.004 < 0.05) Total soil erosion in year-1 and year-5 were 21.84 ton/ha/6months and 14.20 ton/ha/6months, respectively that is classified as strong erosion (level IV) base on TCVN5299:2009; (3) both runoff and soil erosion at different ages of Acacia plantation forest has strongly depended on the amount of precipitation (R2 range from 0.52-0.85, with P-value = 0.00) This suggests that the amount of runoff and soil erosion at Acacia 1-year-old was a greater amount of soil erosion because of fewer vegetation covers we need to be more concerned and apply suitable management for reducing the negative impact of Acacia plantation forest at the headwater of Vietnam i TABLE OF CONTENT ABSTRACT i TABLE OF CONTENT ii ABBREVIATIONS iv LIST OF TABLES v LIST OF FIGURES vi CHAPTER I: INTRODUCTION CHAPTER II: LITERATURE REVIEW 2.1 Runoff generation and soil erosion globally 2.2 Runoff generation and soil erosion in Vietnam 10 CHAPTER III: STUDY SITE AND METHODS 13 3.1 Study site 13 3.2 Methods 15 3.2.1 Plots design for an experiment 15 3.2.2 Measure runoff 19 3.2.3 Measure soil erosion 20 3.2.4 Measure precipitation 21 3.2.5 Soil moisture measuring 21 3.2.6 Measure porosity of the soil 22 3.2.7 Soil texture 23 3.2.8 Vegetation observation 25 3.2.9 Topographic survey 25 3.3 Data analysis 25 CHAPTER IV: RESULTS 26 4.1 Runoff generation at different ages of Acacia plantation 26 4.2 Soil erosion at different ages of Acacia plantation 30 4.3 The relationship among runoff, soil erosion, and precipitation 35 4.4 Suggested solution 39 ii CHAPTER V: DISCUSSION 41 5.1 Runoff generation at two different ages of Acacia plantation forest 41 5.2 Soil erosion at two different ages of Acacia plantation forest 44 CHAPTER VI: CONCLUSION 49 ACKNOWLEDGMENT 50 REFERENCES APPENDIX iii ABBREVIATIONS 1-Down Plot 1-down at Acacia 1-year-old 1-Up Plot 1-up at Acacia 1-year-old 5-Down Plot 5-down at Acacia 5-years-old 5-Up Plot 5-up at Acacia 5-years-old API7 Antecedent precipitation index for days C Carbon Cm3 Cubic centimeter df Degree of freedom FAO Food and Agriculture Organization Fig Figure GIS Geography Information System GPS Global position system Hectare N-P-K Nitrogen - Phosphorus - Potassium P-value Probability R2 Coefficient of determination RUSLE Revised Universal Soil Loss Equation SPSS Statistical Package for the Social Sciences USA United States of America USDA US Department of Agriculture iv LIST OF TABLES Table 3.1 Observation plots characteristic at the study site 17 Table 3.2 Soil texture at study site follow FAO classification 2006 17 Table 4.1 The summary result from SPSS (Appendix table1) 30 Table 4.2 The summary result from SPSS (Appendix table 1) 34 Table 4.3 Summary of correlation analysis between runoff, soil erosion, and both rainfall and soil moisture characteristics 38 Table 4.4 TCVN5299: 2009 Method for determination of soil erosion by rainfall 39 Table 5.1 Comparison the runoff coefficient with other studies (the unit for first two columns are %/6months while the rests are a %/1 year) 43 Table 5.2 Compare the soil erosion among Acacia plantation forest year-1, year-5 (ton/ha/6months) with other land types (ton/ha/year for the rest) 47 v LIST OF FIGURES Fig 2.1 Soil erosion effect by human impact in Madagascar, (Source: US news) Fig 2.2 Soil erosion by water globally (ton/ha/year) Fig 2.3 Soil erosion in Lai Chau after heavy rain in June 2018 .12 Fig 3.1 The map of the study site: a) Location of Hoa Binh province on Viet Nam map, b) Contour line map of four plots location; c) Acacia 1-year-old; d) Acacia 5years-old .14 Fig 3.2 Picture a) Contour line map shows the location of four plots, b) Model illustrates elevation, slope, and distance of plots at the study site 16 Fig 3.3 Picture plot 1-down and 1-up of Acacia 1-year-old and, plot 5-down and plot 5-up of Acacia 5-years-old planation forest at study site .16 Fig 3.4 The model of plot and experiment conducted, a) gutter, b) plastic tube, c) aluminum sheet, d) plastic container 18 Fig 3.5 A measured amount of runoff 19 Fig 3.6 Took eroded soil to dried and weighted in the Laboratory 20 Fig 3.7 US standard plastic rain gauge 21 Fig 3.8 (a) Bulk density tube, (b) took a soil sample, (c) soil sample keep in zipper plastic bag, (d) measured wet soil .23 Fig 3.9 (A) Removed fraction, (B) rock and roots, (C) soil after grind and (D)pipette 24 Fig 4.1 Runoff generation and precipitation at the study site 26 Fig 4.2 Runoff coefficient from four plots .27 Fig 4.3 Runoff accumulation and precipitation from four plots 28 Fig 4.4 Runoff generation box chat plot 29 Fig 4.5 Precipitation and soil erosion from four plots .31 Fig 4.6 Soil erosion accumulation from four plots 31 Fig 4.7 Soil erosion box chat plot 33 vi Fig 4.8 The model illustrates the result of runoff and soil erosion at two different ages of Acacia plantation forest from April to September 2018 34 Fig 4.9 Correlation between precipitation and runoff from four plots 35 Fig 4.10 Correlation between soil erosion and precipitation from four plots 36 Fig 4.11 Correlation between soil erosion and runoff from four plots 37 vii CHAPTER I: INTRODUCTION Runoff and erosion are considered the main cause of soil and water resources degradation (Clement et al., 2006; Yang et al., 2003) Runoff is a process of water surface flow, other sources flow over the earth’s surface Runoff is one of the main factors that support for non-point source pollution It’s also the main cause of sediment delivery to stream and river (Braskerud, 2002) However, sometimes runoff can start before all surface depressions have been filled (Moore and Larson, 1979) Erosion is the action of the surface process of soil due to a water drop and wind, under the impact of gravity on earth (Ellison, 1945) Previous researches indicated that runoff and erosion have a close relationship with precipitation (Ramos‐ Scharrón and MacDonald, 2007) Soil erosion is a natural phenomenon but this phenomenon is becoming more serious (Hudson, 1995) It not only directly affects the agroforestry production activities but also affects the environment and the life of the downstream communities as land degrades rapidly in all aspects: chemistry, physics, and biology (Joseph, 2005) The characteristics of runoff and erosion will have a direct impact on soil quality, stream health and water quality In the rapid developing speed of the world, the environmental problem has emerged as one of the most important challenges that the world together must face Industrialization and agriculture activities have left behind serious impact on the natural condition Globally Soil erosion has been an environmental concern in such countries as China and those bordering the Mediterranean Sea for millennia (Morgan, 2009) The potential of soil loss estimated is about 0.38mm/year The most seriously affected region in the world in Southeast Asia It nearly 60% of present soil erosions are induced by human activity, global warming, the increasing trend of precipitation and population (Yang et al., 2003) Erosion happens quite frequently in Asia, Africa and South America with the soil mass from 30 to 40 tons per hectare for every year (Barrow, 1991) In Cambodia, the degradation of soil and water quality will lead to REFERENCES Altieri, M.A., 1999 The ecological role of biodiversity in agroecosystems, in: Invertebrate Biodiversity as Bioindicators of Sustainable Landscapes Elsevier, pp 19–31 Ananda, J., Herath, G., 2003 Soil erosion in developing countries: a socioeconomic appraisal J Environ Manage 68, 343–353 Barbier, E.B., Bishop, J.T., 1995 Economic values and incentives affecting soil and water conservation in developing countries J Soil Water Conserv 50, 133– 137 Barrow, C.J., 1991 Land degradation: development and breakdown of terrestrial environments Cambridge University Press Bauters, T., Steenhuis, T., DiCarlo, D., Nieber, J., Dekker, L., Ritsema, C., Parlange, J.-Y., Haverkamp, R., 2000 Physics of water repellent soils J Hydrol 231, 233–243 Bonell, M., 1998 SELECTED CHALLENGES IN RUNOFF GENERATION RESEARCH IN FORESTS FROM THE HILLSLOPE TO HEADWATER DRAINAGE BASIN SCALE JAWRA J Am Water Resour Assoc 34, 765–785 Braskerud, B., 2002 Factors affecting phosphorus retention in small constructed wetlands treating agricultural non-point source pollution Ecol Eng 19, 41– 61 Bruijnzeel, L.A., 2004 Hydrological functions of tropical forests: not seeing the soil for the trees? 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at hillslope scale in Lanjaron, Spain Environmentalist 24, 39–48 Zuazo, V.H.D., Pleguezuelo, C.R.R., 2009 Soil-erosion and runoff prevention by plant covers: a review, in: Sustainable Agriculture Springer, pp 785–811 APPENDIX Appendix 1: Plots descriptive statistic Plot N Minimum Maximum Sum Mean Std Deviation 1- 55 0.00 1.3 20.0 0.36 0.28 1-up 55 0.00 1.4 25.5 0.46 0.34 5- 55 0.00 1.5 22.3 0.35 0.32 5-up 55 0.00 1.1 21.1 0.39 0.27 1- 55 0.00 1.01 8.84 0.16 0.18 down Runoff coefficient (%) down down Runoff 1-up 55 0.00 1.1 10.90 0.20 0.20 (mm) 5- 55 0.00 1.4 11.11 0.17 0.27 5-up 55 0.00 0.71 9.72 0.18 0.18 1- 55 0.00 8505.58 217385.24 3952.5 2312.1 1-up 55 0.00 11352.4 298316.4 5423.9 3113.8 5- 55 0.00 6183.9 188709.03 3431.1 1790.9 55 0.00 6723.1 213115.3 3874.8 1820.2 down down Soil erosion (g/15m2) down 5-up Appendix Monitored storm event, runoff, and erosion Day Precipitation Rainfall intensity API7 (mm) (mm/h) Runoff (mm) Runoff coefficient Soil loss (g) (mm) 1-down 1-up 5-down 5-up 1-down 1-up 5-down 5-up 1-down 1-up Soil loss (mm) 5-down 5-up 1-down 1-up 5-down 5-up 22/4/2018 32.0 9.85 0.0 0.17 0.21 0.11 0.18 0.5 0.6 0.3 0.6 205.5 325.8 155.3 235.2 0.005 0.008 0.004 0.006 25/4/2018 43.5 9.00 10.7 0.28 0.32 0.20 0.23 0.6 0.7 0.5 0.5 385.7 446.6 185.0 261.6 0.010 0.011 0.005 0.007 30/4/2018 35.7 8.39 8.7 0.21 0.25 0.12 0.20 0.6 0.7 0.3 0.6 250.0 350.1 167.2 250.8 0.006 0.009 0.004 0.006 3/5/2018 28.8 11.52 11.9 0.16 0.17 0.10 0.13 0.5 0.6 0.4 0.5 180.1 220.2 145.2 210.2 0.005 0.006 0.004 0.005 5/5/2018 24.8 7.82 21.5 0.12 0.15 0.09 0.11 0.5 0.6 0.4 0.4 150.6 200.3 100.5 150.1 0.004 0.005 0.003 0.004 8/5/2018 29.0 8.69 14.0 0.14 0.16 0.11 0.12 0.5 0.5 0.4 0.4 156.2 199.2 150.1 170.9 0.004 0.005 0.004 0.004 12/5/2018 54.0 11.57 10.8 0.34 0.35 0.21 0.29 0.6 0.7 0.4 0.5 545.3 572.4 293.9 468.4 0.014 0.014 0.007 0.012 13/5/2018 7.3 5.80 59.8 0.00 0.00 0.00 0.00 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.000 0.000 0.000 0.000 16/5/2018 10.9 7.27 16.0 0.05 0.11 0.03 0.04 0.5 1.0 0.3 0.4 0.0 0.0 0.0 0.0 0.000 0.000 0.000 0.000 18/5/2018 42.0 13.26 15.9 0.24 0.32 0.19 0.44 0.6 0.8 0.5 1.1 344.5 466.9 240.8 329.4 0.009 0.012 0.006 0.008 19/5/2018 5.0 2.02 54.5 0.00 0.00 0.00 0.00 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.000 0.000 0.000 0.000 21/5/2018 12.0 3.88 18.7 0.07 0.13 0.04 0.05 0.6 1.1 0.3 0.4 0.0 0.0 0.0 0.0 0.000 0.000 0.000 0.000 24/5/2018 5.7 5.70 12.0 0.00 0.00 0.00 0.00 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.000 0.000 0.000 0.000 26/5/2018 34.5 9.41 6.0 0.12 0.19 0.18 0.28 0.4 0.6 0.5 0.8 110.8 297.0 301.3 308.1 0.003 0.007 0.008 0.008 27/5/2018 83.6 13.19 38.3 0.30 0.41 1.27 0.51 0.4 0.5 1.5 0.6 350.3 488.4 727.5 530.2 0.009 0.012 0.018 0.013 28/5/2018 6.1 2.98 108.5 0.00 0.00 0.00 0.00 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.000 0.000 0.000 0.000 29/5/2018 20.0 15.0 46.6 0.03 0.05 0.05 0.06 0.2 0.3 0.2 0.3 0.0 0.0 0.0 0.0 0.000 0.000 0.000 0.000 30/5/2018 14.5 8.70 60.4 0.00 0.00 0.00 0.00 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.000 0.000 0.000 0.000 1/6/2018 14.2 6.53 37.9 0.00 0.00 0.00 0.00 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.000 0.000 0.000 0.000 2/6/2018 59.5 11.16 44.0 0.18 0.27 0.79 0.52 0.3 0.5 1.3 0.9 110.5 382.1 472.5 380.2 0.003 0.010 0.012 0.010 4/6/2018 54.5 40.88 41.6 0.10 0.19 0.16 0.27 0.2 0.4 0.3 0.5 80.7 160.1 110.5 215.8 0.002 0.004 0.003 0.005 6/6/2018 6.5 4.88 47.0 0.00 0.00 0.00 0.00 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.000 0.000 0.000 0.000 9/6/2018 2.5 1.50 21.5 0.00 0.00 0.00 0.00 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.000 0.000 0.000 0.000 10/6/2018 25.5 20.68 13.2 0.02 0.02 0.15 0.10 0.1 0.1 0.6 0.4 0.0 0.0 0.0 0.0 0.000 0.000 0.000 0.000 11/6/2018 7.5 3.26 35.8 0.01 0.01 0.01 0.02 0.1 0.2 0.1 0.3 0.0 0.0 0.0 0.0 0.000 0.000 0.000 0.000 14/6/2018 5.0 4.57 9.3 0.00 0.00 0.00 0.00 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.000 0.000 0.000 0.000 16/6/2018 19.5 7.31 8.6 0.01 0.02 0.05 0.03 0.1 0.1 0.3 0.2 0.0 0.0 0.0 0.0 0.000 0.000 0.000 0.000 19/6/2018 117.5 17.63 7.5 0.24 0.37 1.36 0.71 0.2 0.3 1.2 0.6 20/6/2018 2.3 1.13 123.2 0.00 0.00 0.00 0.00 0.0 0.0 0.0 0.0 112.1 394.3 0.0 0.0 539.5 389.8 0.003 0.010 0.014 0.010 0.0 0.0 0.000 0.000 0.000 0.000 28/6/2018 9/7/2018 24.0 21.3 11.08 7.08 0.0 0.02 0.02 0.07 0.05 0.1 0.1 0.3 0.2 0.0 0.0 0.0 0.0 0.000 0.000 0.000 0.000 0.0 0.01 0.03 0.05 0.08 0.1 0.2 0.2 0.4 0.0 0.0 0.0 0.0 0.000 0.000 0.000 0.000 70.5 115.2 205.1 220.9 0.002 0.003 0.005 0.006 10/7/2018 59.5 7.93 21.3 0.09 0.17 0.33 0.50 0.1 0.3 0.6 0.8 20/7/2018 64.0 6.92 0.0 0.30 0.40 0.37 0.53 0.5 0.6 0.6 0.8 390.6 490.5 208.2 235.1 0.010 0.012 0.005 0.006 21/7/2018 44.0 7.54 64.0 0.24 0.30 0.13 0.14 0.5 0.7 0.3 0.3 285.3 400.8 96.6 100.2 0.007 0.010 0.002 0.003 22/7/2018 49.5 6.19 76.0 0.27 0.31 0.17 0.18 0.5 0.6 0.3 0.4 375.4 422.5 110.5 125.1 0.009 0.011 0.003 0.003 23/7/2018 32.5 5.27 92.8 0.17 0.21 0.11 0.15 0.5 0.7 0.0 0.5 210.6 320.6 99.1 105.0 0.005 0.008 0.002 0.003 24/7/2018 24.5 7.74 87.9 0.12 0.17 0.03 0.04 0.5 0.7 0.1 0.2 0.0 0.0 0.0 0.0 0.000 0.000 0.000 0.000 26/7/2018 52.5 6.85 44.8 0.29 0.32 0.18 0.21 0.6 0.6 0.3 0.4 350.7 423.1 112.2 130.0 0.009 0.011 0.003 0.003 28/7/2018 73.5 5.80 57.7 0.83 0.93 0.61 0.61 1.1 1.3 0.8 0.8 500.0 510.2 250.1 270.2 0.013 0.013 0.006 0.007 29/7/2018 81.0 7.48 108.3 1.01 1.13 0.66 0.67 1.3 1.5 0.8 0.8 530.3 585.6 251.1 271.2 0.013 0.015 0.006 0.007 13/8/2018 35.0 6.00 0.0 0.19 0.23 0.23 0.17 0.6 0.7 0.7 0.5 220.0 320.0 100.8 111.2 0.006 0.008 0.003 0.003 14/8/2018 29.0 9.67 35.0 0.13 0.18 0.18 0.11 0.4 0.6 0.6 0.4 102.0 120.0 85.7 95.1 0.003 0.003 0.002 0.002 16/8/2018 52.0 8.00 26.2 0.28 0.30 0.30 0.23 0.5 0.6 0.6 0.4 320.0 370.0 120.0 140.1 0.008 0.009 0.003 0.004 18/8/2018 22.0 8.80 37.0 0.10 0.13 0.13 0.04 0.5 0.6 0.6 0.2 0.0 0.0 0.0 19/8/2018 47.0 12.53 50.9 0.23 0.28 0.28 0.19 0.5 0.6 0.6 0.4 280.0 340.0 0.0 0.000 0.000 0.000 0.000 105.1 113.1 0.007 0.009 0.003 0.003 20/8/2018 31.0 5.47 80.8 0.14 0.19 0.19 0.12 0.5 0.6 0.6 0.4 108.0 120.0 86.3 96.2 0.003 0.003 0.002 0.002 22/8/2018 33.5 7.44 45.2 0.17 0.21 0.21 0.15 0.5 0.6 0.6 0.4 210.0 311.0 99.1 105.0 0.005 0.008 0.002 0.003 24/8/2018 33.0 7.33 73.8 0.16 0.21 0.21 0.17 0.5 0.6 0.6 0.5 200.0 309.0 100.0 109.5 0.005 0.008 0.003 0.003 26/8/2018 42.0 8.69 35.8 0.21 0.24 0.24 0.18 0.5 0.6 0.6 0.4 244.0 323.0 108.5 110.2 0.006 0.008 0.003 0.003 27/8/2018 44.0 5.50 64.1 0.22 0.25 0.25 0.19 0.5 0.6 0.6 0.4 251.0 325.0 103.7 112.0 0.006 0.008 0.003 0.003 28/8/2018 50.0 5.56 85.8 0.25 0.27 0.27 0.21 0.5 0.5 0.5 0.4 290.0 333.0 113.6 121.3 0.007 0.008 0.003 0.003 29/8/2018 55.0 5.50 97.4 0.28 0.31 0.31 0.23 0.5 0.6 0.6 0.4 325.0 380.0 120.0 130.7 0.008 0.010 0.003 0.003 30/8/2018 51.0 4.64 110.7 0.24 0.27 0.27 0.22 0.5 0.5 0.5 0.4 260.0 330.0 119.0 120.4 0.007 0.008 0.003 0.003 31/8/2018 21.0 7.88 112.1 0.08 0.10 0.10 0.03 0.4 0.5 0.5 0.2 0.0 0.0 0.0 0.0 0.000 0.000 0.000 0.000 3/9/2018 12.0 6.86 45.4 0.00 0.00 0.00 0.00 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.000 0.000 0.000 0.000 0.0