MINISTRY OF EDUCATION AND MINISTRY OF AGRICULTURE AND RURAL TRAINING DEVELOPMENT VIETNAM NATIONAL UNIVERSITY OF FORESTRY  SENG RAVOR SOIL PROPERTIES IN RUBBER PLANTATION AND ECONOMIC EFFICIENCY IN THACH THANH DISTRICT, THANH HOA 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  SENG RAVOR SOIL PROPERTIES IN RUBBER PLANTATION AND ECONOMIC EFFICIENCY IN THACH THANH DISTRICT, THANH HOA PROVINCE, VIETNAM Major: Forest Science Code: 8620201 MASTER THESIS IN FOREST SCIENCE Signature: …………………………… Academic advisor: Dr PHI DANG SON Hanoi, 2018 Abstract In Vietnam land use for rubber is in the south region; however in the north of Vietnam still some areas are suitable for natural rubber farming The soil is recommended to all stakeholders who want to become rubber farm owner There are not many studies existed on the effect of rubber plantation on soil properties and the sustainability of agricultural development in Vietnam This study aimed to evaluate the effects of rubber and turmeric land use on soil property from 0-105 cm depth and separated to two layers (topsoil from 0-30 cm and subsoil at 40105 cm) The results have shown that soil texture almost clay Soil physical property such as soil porosity was 63.43% highest in turmeric farm and the lowest was 43.10% in the rubber plantation established in 1999 The percentages of soil moisture at 0-30 cm depth was significance at p-value = 0.000 < 0.05 whereas, at 40-105 cm depth not-significant difference under rubber planted in 2007 at p-value = 0.135 > 0.05 The soil density was significantly different at p-value = 0.010 at the topsoil Soil bulk density (g/cm3) at topsoil such as the rubber plantation was created in 1999, 2017, turmeric and rubber-turmeric there is no-significant difference at p-value = 0.091 That all soils were acidic in land use types Soil chemical property such as nitrogen content has no significance different in land used types especially, highest at 40-105 cm depth and the p-value was 0.911 In the rubber and turmeric farms the phosphorous content there were significance different particularly, at subsoil in rubber-turmeric (p-value = 0.000) and the carbon content in topsoil with the highest content in rubber-turmeric was 3.453 mg/100g and lowest in turmeric farm was 2.356 mg/100g of soils while, the carbon content from 40-105 cm were lower significant difference existed in rubber and turmeric farms was (p-value = 0.007) This suggests that fertilizers including chemical and organic to make crop root systems better to uptake nutrients from soil depths easily To explain the prices of rubber, turmeric and sugarcane, data obtain from surveys were conducted in Thanh Hoa province, Vietnam that rubber was started from last i decades The price of natural rubber always fluctuation in lower, almost rubber growers have suggested, led to wish to change the crops and major problems Agricultural diversifications have done recommend to all rubber growers during rubber still young age due to enough spaces to practices The price of rubber in 2018 in Thach Thanh and Cam Thuy districts, Thanh Hoa province was 25,000 VND per kg, turmeric was 6,000 NVD per kg and sugarcane was 900 to 1,000 VND per kg ii Table of Content Abstract i List of figure v List of table vi Abbreviation vii CHAPTER I: INTRODUCTION 1.2.1 Goal 1.2.2 Specific objectives 1.2.3 Research questions CHAPTER II: LITERATURE REVIEW 2.1 General overview rubber plantation in the world and in Vietnam 2.1.1 Rubber plantation history in the world 2.1.2 Rubber plantation in Vietnam 2.1.3 Biological characteristics of rubber 2.1.4 Natural condition requirements of rubber 2.2 Soil quality indicators 10 2.2.1 Soil texture 10 2.2.2 Soil bulk density 10 2.2.3 Soil density 11 2.2.4 Soil porosity 11 2.2.5 pH of the soil 12 2.2.6 Soil moisture 13 2.2.7 Nitrogen 13 2.2.8 Phosphorus 13 2.2.9 Carbon 14 2.3 Natural rubber-intercropping 14 2.3.1 Challenges of intercropping in a rubber plantation 16 2.3.2 Benefits of intercropping in a rubber plantation 16 2.4 Economic 17 2.4.1 Marketing management 17 2.4.2 Labour management 17 CHAPTER III: RESEARCH METHODOLOGY 19 3.1 Brief of Thach Quang Farm 19 3.1.1 Geographic of the location 19 3.1.2 Topography 20 iii 3.1.3 The climate 20 3.1.4 The Soil 21 3.1.5 The Vegetation 21 3.1.6 The Economic 21 3.1.7 The land use in Thach Quang Farm 22 3.1.8 Labour and employment 23 3.2 Data collection 25 3.3 Data analysis 26 3.3.1 Laboratory processing 26 CHAPTER IV: RESULTS AND DISCUSSION 28 4.1 SOIL PHYSICAL PROPERTY 28 4.1.1 Soil texture 28 4.1.2 Soil porosity 31 4.1.3 Soil moisture content 32 4.1.6 Dynamic of soil pH level 37 4.2 SOIL CHEMICAL PROPERTY 39 4.2.1 Total content of nitrogen, phosphorus and carbon 39 4.3 ECONOMIC EFFICIENCY OF RUBBER, SUGARCANE AND TUMERIC CROPS 41 4.3.1 Evaluation of household‟s economic efficiency of rubber owners 41 4.3.2 Relationship between income and socio-economic growers and agronomic characteristics of rubber 42 4.3.3 The opinions of farmers on the rubber, sugarcane and turmeric crops 44 4.4 Recommendation 45 CHAPTER V: CONCLUSION 46 ACKNOWLEDGEMENT 48 REFERENCES 49 APPENDIX 53 iv List of figure Figure 2.1 Map of rubber plantation areas in the world…………………………………… Figure 2.3 Possible pH ranges under the natural soil…………………………………… 12 Figure 3.1 Map of study area…………………………………………………………… 19 Figure 3.2 Plot design…………………………….……………….……………………… 25 Figure 4.1 Particle size compositions of soil texture in rubber and turmeric land use types at topsoil …………………………………… 29 Figure 4.2 Particle size compositions of soil texture in rubber and turmeric land use types at subsoil …………………………………… 30 Figure 4.3 Soil porosity in rubber and turmeric land use types at topsoil ………….….….31 Figure 4.4 Soil moisture in rubber and turmeric land use types at topsoil ………… … 33 Figure 4.5 Soil moisture in rubber and turmeric land use types at subsoil…… …33 Figure 4.6 Soil density in rubber and other plantation at topsoil……………………… 34 Figure 4.7 Soil bulk density in rubber and other plantation at topsoil………………… 36 Figure 4.8 Soil pH (H2O) unit in rubber and turmeric land use types at topsoil… 37 Figure 4.9 Soil pH (H2O) unit in rubber and turmeric land use types at subsoil……… 37 Figure 4.10 Soil pH (KCl) unit in rubber and turmeric land use at topsoil ….………… 38 Figure 4.11 Soil pH (KCl) unit in rubber and turmeric land use at topsoil ….………… 38 Figure 4.12 Evaluation of household‟s economic efficiency of rubber, sugarcane and turmeric owners……………………………………………………………………… 42 Figure 4.13 Opinions of farmers on the rubber, sugarcane and turmeric crops ……… 44 v List of table Table 2.1 Rubber areas, production and average annual yield Table 3.1 Land use in the Thach Quang farm 22 Table 3.2 Employing situation at Thach Quang farm .23 Table 4.1 Summary result from SPSS (Soil texture at topsoil in rubber and turmeric land use) 30 Table 4.2 Summary result from SPSS (Soil texture at subsoil in rubber and turmeric land use) .30 Table 4.3 Summary result from SPSS (Soil porosity in rubber and turmeric land use) .32 Table 4.4 Summary result from SPSS (Soil moisture in rubber and turmeric land use) 33 Table 4.5 Summary result from SPSS (Soil density in rubber and turmeric land use) 34 Table 4.6 Summary result from SPSS (Bulk density in rubber and turmeric land use) 36 Table 4.7 Summary result from SPSS (Soil pH (H2O) in rubber and turmeric land use) 38 Table 4.8 Summary result from SPSS (Soil pH (KCl) in rubber and turmeric land use) 40 Table 4.9 Chemical property of soil under rubber, turmeric and rubber-turmeric farms (mg/100g) 41 Table 4.10 Summary result from SPSS (Total content of N, P and C in rubber and turmeric land use types) .41 Table 4.11 The relationship between income and socio-economic growers and agronomic characteristics of rubber 43 vi Abbreviation ANRPC = Association of Natural Rubber Producing Countries A(n) = Annuity C = Carbon Df = Degree of freedom VND = Vietnamese Dong g/cm3 = Gram per cubic centimetre GDP = gross national product Ha = Hectare KCl = Potassium chloride M (%) = Moisture content Mw = Mass of waters Ms = Mass of solids NR = Natural rubber N = Nitrogen pH = Power of hydrogen P = Phosphorous PV = Present value RB = Rubber RSS = Ribbed smoked sheets TSR = Technically specified rubber vii CHAPTER I: INTRODUCTION 1.1 Background Rubber is a very good economic, useful and valuable crop to companies and farmers in Southeast Asia In recent decades rubber has attracted a great number of scientists focusing on practices for propagations and cultivation methods which includes nutrition management and mixed cropping species plantations with rubber trees Rubber-mixed with other crops are more valuable in term of income This study will provide information and awareness of soil properties on rubber and arable farms conditions to the local people in Thach Thanh district, Thanh Hoa province Rubber tree (Hevea brasiliensis) is a good species that crucial to producing natural latex The conversion from tropical forest to rubber plantation can change the soil properties, for examples, soil organic matter content, nitrogen and soil moisture (Li et al., 2012) In the Southeast region of Viet Nam, rubber trees are encouraged to plant where suitable climate are fullfil for rubber plantation The mountainous and coastal area in the north of Vietnam, cultivation of rubber crop has been subsequently expanded Even annual rainfall is enough in the rainy season but, around months are in dry has marked often suffer to these regions The average of temperature in the Northern Mountains in some months are coldest can even reach 16 oC It means that the temperature in south of Vietnam is remarkable higher than North Vietnam in some months (Tran and Nguyen, 2016) The changing effects are normally externalized, for the whole society is being higher than farming operating Farm size extension with mechanization using is increased Crop conversions and noncrop features losing in diversity have been decreasing (Stoate et al., 2001) The soil properties under rubber at different ages were analyzed and compared to check the changing of physical and chemical properties During the first 18 years, the changing of total soil porosity and bulk density content were slight The results APPENDIX Appendix 2a: Soil texture Plot RB 1999 RB 2007 Turmeric RubberTurmeric Silt Topsoil 41.09 35.07 31.84 45.82 44.21 42.05 35.95 35.97 32.78 43.02 38.42 37.58 Subsoil 38.77 34.55 41.80 28.84 38.65 33.01 32.44 51.21 39.76 37.91 47.38 41.43 Clay Topsoil Subsoil 50.20 44.56 43.03 41.27 46.35 33.18 32.25 46.23 37.33 46.35 44.78 53.17 45.96 47.28 48.44 29.78 50.90 44.94 44.85 50.87 41.99 32.42 44.32 47.09 Sand Topsoil Subsoil 50.20 44.56 43.03 41.27 46.35 33.18 32.25 46.23 37.33 46.35 44.78 53.17 45.96 47.28 48.44 29.78 50.90 44.94 44.85 50.87 41.99 32.42 44.32 47.09 Appendix 2b: Soil physical properties Plot RB 1999 RB 2007 Turmeric RubberTurmeric Porosity 43.07 43.26 42.7 53.14 56.25 48.56 54.6 69.13 66.57 58.02 54.13 60.2 Soil physical properties (Topsoil) Density Bulk density 1.25 2.64 1.15 2.59 1.32 2.58 1.26 2.68 1.28 2.64 1.22 2.56 1.14 2.85 1.13 2.82 1.17 2.82 1.22 2.78 1.23 2.61 1.28 2.58 56 Appendix 2c: Soil moisture Plot RB 1999 RB 2007 Turmeric RubberTurmeric Soil moisture Topsoil Subsoil 26.19 33.63 27.99 30.57 27.06 33.05 32.58 33.25 31.58 31.79 31.05 35.72 28.58 32.50 29.32 33.91 28.50 34.56 33.74 35.74 32.93 34.33 36.81 39.05 Appendix 2d: Soil pH Plot RB 1999 RB 2007 Turmeric RubberTurmeric pH (H2O) Topsoil Subsoil 5.3 5.7 5.4 5.7 5.7 4.8 5.6 5.8 5.4 5.5 5.1 5.7 5.8 4.8 5.5 5.2 4.9 5.5 6.4 5.5 5.7 5.5 5.7 57 pH (KCl) Topsoil Subsoil 3.8 3.8 4 3.9 4 3.9 3.8 3.9 4.8 3.8 4.7 3.8 4.8 4.2 4.4 4.8 4.3 4.8 4.2 4.7 Appendix 2e: Soil chemical properties Plot RB 1999 RB 2007 Turmeric RubberTurmeric Nitrogen Topsoil Subsoil 0.03 0.06 0.03 0.04 0.09 0.08 0.01 0.08 0.01 0.15 0.02 0.03 0.03 0.13 0.04 0.05 0.06 0.05 0.07 0.06 0.04 0.04 0.14 0.13 Phosphorous Topsoil Subsoil 0.2 0.13 0.23 0.03 0.13 0.45 0.39 0.18 0.68 0.19 0.7 0.1 0.14 1.26 0.1 1.07 0.31 1.68 0.61 0.1 0.65 0.11 0.88 0.09 58 Carbon Topsoil Subsoil 2.74 1.7 2.2 1.8 2.21 1.49 1.7 2.21 3.6 1.57 2.35 1.71 2.56 2.57 2.24 2.95 2.27 3.86 3.97 2.56 3.74 2.18 2.65 2.31 APPENDIX Appendix 3a: Rubber plantation (Smallholders) GENERAL INFORMATION Name……………………….… Occupation ………………………… Age……………………… … Gender: Male Female Hamlet………………………… Commune ………………… District………………… … 1.1 Type of family system Intensive Improve extensive Integrated rubber-other crops 1.2 The plantation Total area …………………….…ha The name of clone………………and How old is rubber………………….…years Rubber…………… Other crops ……………… Did you contract farming with the company: Yes No If yes, why ………………………………………………………………………………… ……………………………………………………………………………………………… CURRENT MANAGEMENT 2.1 How did you prepare the site of planting? Soil preparation/ clearing ……………………………………………………………………………………………… ……………………………………………………………………………………………… ……………………………………………………………………………………………… How much did you cost for soil preparation/cleaning……………………………VND/ha Planting pit (dug pits): By machinery by hand Size of pit ……………….……… Planting density ……………….… Did you use fertilizer: Yes No What kind of fertilizer did you use to put into pits……………………………………… … 59 How much did you put………………………… ….kgs/pit How many……………………………………… ….bags/ha How many ……………………………………… …kgs/bag EXPENDITURE FOR RUBBER PLANTATION 3.1 Where did you obtain the planting stock? Nursery Purchased If nursery, how much did you cost …………………… VND/ If purchased, how much did you cost ………………… VND/ Other………………………………………………………………………………………… 3.2 Planting Planting by: Yourself Labour Both How much did you cost to transport form nursery to plantation……………………VND/ha Plating cost……………………… VND/ha Replanting…………………………VND/ha Labour……………………… ……VND/ha per month Other………………………………………………………………………………………… …………………………………………………………………… ………………………… 3.3 Fertilizer using: Did you use fertilizer? Yes No If used, Could you help to explain? Fertilizer/year1 …….… …time/ ha…………….VND/time………….……….VND/year Fertilizer/year2 ……… …time/ ha………… VND/time…….……….……VND/year Fertilizer/year3 …… ……time/ ha…………… VND/time……….…………VND/year Fertilizer/year4 …… ……time/ ha………… VND/time…….…………….VND/year Fertilizer/year5 …… ……time/ ha………… VND/time…….…………….VND/year Fertilizer/year6 …….… …time/ ha…………… VND/time………….………VND/year Fertilizer/year7 ……… …time/ ha………… VND/time…….……….… VND/year Fertilizer/year8 …… ……time/ ha………… …VND/time……….…………VND/year Fertilizer/year9 …… ……time/ ha………… VND/time…….……………VND/year Fertilizer/year10 …… ….time/ ha………… VND/time…….……………VND/year Fertilizer/year11 ……….…time/ ha…………… VND/time………….………VND/year 60 Fertilizer/year12 ……….…time/ ha…………… VND/time…….….…….….VND/year Fertilizer/year13:…… … time/ ha………… …VND/time…….……………VND/year Fertilizer/year14: ……….…time/ ha…………….…VND/time………….………VND/year Fertilizer/year15: ……….…time/ ha………… …VND/time…….……….……VND/year 3.4 Pest and weed controlling: Did you use them? (Pesticides, Insecticides, Herbicides and Fungicides) Yes No If used, can you help to explain? How many times did you use, how much per time and how many hours per time? - Pesticides……… times/ha, How much…………… VND/time……………hours/time - Insecticides…… times/ha, How much…………… VND/time……………hours/time - Herbicides……… times/ha, How much…………… VND/time……………hours/time - Fungicides……… times/ha, How much…………… VND/time……………hours/time Can you explain from year by year? Year1…………………VND/ ha, Dosage/ha………………… time to use………….…… Year2…………………VND/ ha, Dosage/ha………………… time to use………….…… Year3…………………VND/ ha, Dosage/ha………………… time to use………….…… Year4…………………VND/ ha, Dosage/ha………………… time to use…………….… Year5…………………VND/ ha, Dosage/ha………………… time to use…………….… Year6…………………VND/ ha, Dosage/ha………………… time to use…………….… Year7…………………VND/ ha, Dosage/ha………………… time to use…………….… Year8…………………VND/ ha, Dosage/ha………………… time to use…………….… Year9…………………VND/ ha, Dosage/ha………………… time to use…………….… Year10……….….……VND/ ha, Dosage/ha………….….… time to use……… …… Year11………….….…VND/ ha, Dosage/ha………………….time to use……… ….… Year12………….….…VND/ ha, Dosage/ha………… …….time to use……… ….… Year13…………… …VND/ ha, Dosage/ha………… …….time to use……… ….… Year14………….….…VND/ ha, Dosage/ha………… …….time to use……… ….… Year15…………… …VND/ ha, Dosage/ha………… …….time to use……… ….… 3.5 Did you pruning the rubber trees farm Yes No 61 If yes, at what age………… to …………years Pruning…………… time/year1……….……VND/time and …………… …… VND/year Pruning…………… time/year2……….……VND/time and ………… ……… VND/year Pruning…………… time/year3……….……VND/time and …………… …… VND/year Pruning…………… time/year4……….……VND/time and …………… …… VND/year Pruning…………… time/year5……….……VND/time and …………… …… VND/year Pruning…………… time/year6…….………VND/time and …………… …… VND/year What did you use the pruning for? Firewood Sale Other………………………………………………………………………………………… ……………………………………………………………………………… ……………… If sold, pleas detail Year1……………… VND/ha Year2……………… VND/ha Year3……………… VND/ha Year4……………… VND/ha Year5……………… VND/ha Year6……………… VND/ha HARVESTING SYSTEM How many months per year you use harvest? ………………………………months/year What tapping system are you choosing D2 D3 Other……………………… Rubber tapping S/2 S/3 S/4 Other……………………… Note: D2: tapping every day 2, D3: tapping every day 3, D4: tapping every day Note: S/2: ½ of tree tapping, S/3: 1/3 of tree tapping, S/4: ¼ of tree tapping HARVESTING ACTIVITIES 5.1 Did you plant mixed crops Yes No 62 D4 If planted, what kind of crops did you plant? ……………………………………………………………………………………………… ……………………………………………………………………………………………… Year1………………VND/ and How much…………… VND/kg…….………… kgs/ha Year2………………VND/ and How much…………… VND/kg…….………… kgs/ha Year3………………VND/ and How much…………… VND/kg…….………… kgs/ha Year4………………VND/ and How much…………… VND/kg…….………… kgs/ha Year5………………VND/ and How much…………… VND/kg…….………… kgs/ha Year6………………VND/ and How much…………… VND/kg…….………… kgs/ha 5.2 Natural rubber products What types of natural rubber products sell on the market? Latex Coagulum Smoke Sheet Other If you have, please detail: …………………………………………………………… …… ………………………… ……………………………………………………………………………………………… How much did you earn from sell rubber products? Year1: How many…………………kgs/ha and How much……………….……… VND/kg Year2: How many…………………kgs/ha and How much……………….……… VND/kg Year3: How many…………………kgs/ha and How much………….…………… VND/kg Year4: How many…………………kgs/ha and How much………………….…… VND/kg Year5: How many…………………kgs/ha and How much………………….…… VND/kg Year6: How many…………………kgs/ha and How much………………….…… VND/kg Year7: How many…………………kgs/ha and How much…………………….… VND/kg Year8: How many…………………kgs/ha and How much………………….…… VND/kg Year9: How many…………………kgs/ha and How much………………….…… VND/kg Year10: How many…………… …kgs/ha and How much………………….…… VND/kg Year11: How many…………… …kgs/ha and How much………………….…… VND/kg Year12: How many…………… …kgs/ha and How much……………….……… VND/kg Year13: How many…………… …kgs/ha and How much……………….……… VND/kg Year14: How many…………… …kgs/ha and How much…………………….… VND/kg Year15: How many…………… …kgs/ha and How much…………………….… VND/kg 63 5.3 Transportation What did you use to transport rubber products? Truck Motorbike Other If yes, how much did you cost for: a truck a motorbike ……… VND How much you cost for rubber products transportation………………………VND/day? How much you cost for rubber products transportation……………………VND/month? How much did you cost to fixing truck……………………… VND/month? How much did you cost to fixing truck……………………… VND/year? How much did you cost to fixing motorbike………………… VND/month? How much did you cost to fixing motorbike………………… VND/year? MAJOR PROBLEMS AND PREDICTION Do you have any issue or problem at rubber plantation? Yes No If yes, what are the main problems? …… ………………………………………………………………………………………… ……………………………………………………………………………………………… And why? ……… ……………………………………………………………………………………… …… ……… ……………………………………………………………………………… Can you predict some problems for the future? ……………………………………………………………………………………………… ……………………………………………………………………………………………… Plantation changing Did you change from rubber to other plantations in the past? Yes No hat kind of crop did you plant…………………………………………………………… How about results ………………………………………………………………………… Did you change from other crops to rubber plantation? Yes No Why? ……………………………………………………………………………… ……………………………………………………………………………………………… ……………………………………………………………………………………………… 64 SUGGESTIONS Do you have some suggestions to government or stakeholders to involve you need in nowadays and in the future? Yes No If yes, please mention: ……………………………………………………………………………………………… ……………………………………………………………………………………………… ……………………………………………………………………………………………… ……………………………………………………………………………………………… 65 Appendix 3b: Arable farm GENERAL INFORMATION Name…………………………… Occupation………………………… Age…………………………… Gender: Male Female Hamlet………………………….Commune………………………….… District………………………… 1.1 Type of family system Intensive Improve extensive Integrated with-other crops 1.2 The farm What kind of crop did you plant? Turmeric Sugarcane Total area………………………… Other crops………………………………………………………….…………… ……… CURRENT MANAGEMENT How did you prepare the site of planting or sowing? Soil preparation/ clearing: ……………………………………………………………………………………………… …………………………………………………………………………… ………………… How much did you cost for soil preparation/cleaning……………………………VND/ha By machinery by hand Did you use fertilizer when preparing the soil: Yes No hat kind of fertilizer did you use…………………………………… …………………… How many of fertilizer ………………… kgs/ha How many……………………………… kgs/bag How much did you pay…………………? VND/bag 66 EXPENDITURE FOR ARABLE FARM 3.1 Where did you obtain the planting stock? Nursery Purchased If nursery, how much did you pay ……………………… VND/ If purchased, how much did you pay …………………… VND/ Other………………………………………………………………………………………… 3.2 Planting Planted by yourself Labour Plating or sowing cost……………………… VND/ha Replanting………………………………….…VND/ha Labour…………………………………………VND/ha per month Other……………………………………………………………………………………… 3.3 Fertilizer using: Did you use fertilizer? Yes No If used, How many times/season: ………………… How much did you cost: First ……………….…VND/ …………… Hours/time Second……………… VND/ …………… Hours/time Third………………… VND/ …………… Hours/time Other………………………………………………………………………………………… 3.4 Pest and weed controlling: Did you use them? (Pesticides, Insecticides, Herbicides and Fungicides) Yes No If used, could you help to explain? How many times did you use? - Pesticides………… times/ha, How much…………… VND/time……………hours/time - Insecticides……… times/ha, How much…………… VND/time……………hours/time - Herbicides…… … times/ha, How much…………… VND/time……………hours/time - Fungicides……… times/ha, How much…………… VND/time……………hours/time Can you explain from year by year? First ………………VND/ ha, Dosage/ha………………and time to use…………………… Second…………….VND/ha, Dosage/ha……………….and time to use …… …………… 67 Third………………VND/ha, Dosage/ha……………….and time to use…………… …… Other………………………………………………………………………………………… HARVESTING hat age did you start to harvest…………………………….years? How many times per year you plant? …………………… times/year Other……………………………………………….………………………………………… …………………………………………………………………………………………… HARVESTING ACTIVITIES 5.1 Did you plant mixed with other crops Yes No If planted, what types of crops you plant? ……………………………………………………………………………………………… 5.2 Arable farm products What types of arable products did you sell on the market? ………………………………… ……………………………………………………… … …………………………………… …………………………………………………… … How much did you earn from sell arable farm products? First: How many……… …………kgs/ha and How much……………………… VND/kg Second: How many…………… …kgs/ha and How much……………………… VND/kg Third: How many…………….……kgs/ha and How much……………………… VND/kg Other………………………………………….……………………………………………… ……………………………………………… ……………………………………………… 5.3 Transportation What you transport rubber products? Truck Motorbike other If yes, how much did you cost for: truck motorbike … ……… VND How much did you cost for arable products transportation ………… …VND/time? How much did you cost for arable products transportation…………… ……VND/season? How much did you cost to fixing truck………………………………… VND/season? How much did you cost to fixing truck……………………………… … VND/year? 68 How much did you cost to fixing motorbike………………………………….VND/season? How much did you cost to fixing motorbike…………………………………….VND/year? MAJOR PROBLEMS AND PREDICTION Did you have any issues or problems at your farm? Yes No If yes, what are the main problems? ……………………………………………… ……………………………………………… …………………………………………… ………………………………………………… And why? ……………………………………… ……………………………………………………… ………………………………………………… …………………………………………… Can you predict some problems for the future? ………………………………………………………………… …………………………… ………………………………………………………………… …………………………… PLANTATION CHANGING Did you change from this crop to other crops in the past? Yes No hat kind of crops did you plant…………………………….……………………………… How about results…………………………………………………………………………… hy……………………………………………………………………………………… …………………………………………………………………………… ………………… Do you want to change from this crop to other crops in the future? Yes No What types of crops you wish to change? ……………………………………………………………………………………………… ……………………………………………………………………………………………… hy……………………………………………………………………………………… ……………………………………………………………………………………………… hat does yours expect……………………………………………………………………… ……………………………………………………………………………………………… ……………………………………………………………………………………………… ……………………………………………………………………………………………… 69 SUGGESTIONS Do you have some suggestions to government or stakeholders to involve your requirement in nowadays and in the future? Yes No If yes, please mention: ……………………………………………………………………………………………… ……………………………………………………………………………………………… ……………………………………………………………………………………………… ……………………………………………………………………………………………… 70 ... 4.6 Soil density in rubber and other plantation at topsoil Table 4.5 Summary result from SPSS (Soil density in rubber and turmeric land use) Soil density in rubber and turmeric land use Soil. .. increase the income of smallholders It also helped in maintaining the rubber plantation, increase soil organic matter and improve soil physical and chemical fertility Wide row spacing in rubber plantation. .. Figure 4.9 Soil pH (H2O) unit in rubber and turmeric land use types at subsoil The figure (4.8 & 4.9) shows the soil pH (H2O) in topsoil and subsoil in different land use and rubber plantation