Improving Irrigation Water Use Efficiency of Robusta Coffee (Coffea canephora) Production in Lam Dong Province, Vietnam
Abstract
:1. Introduction
2. Materials and Methods
2.1. Study Area
2.2. Data Collection and Sampling
2.3. Empirical Models
2.3.1. Data Envelopment Analysis (DEA)
Determining Technical Efficiency (TE)
2.3.2. DEA Approach of IWUE
2.3.3. Regression Models
3. Results
3.1. Characteristics of Coffee Farmers
3.2. The Response of Robusta Coffee Productivity to the Level of Irrigation Water Used
3.3. The DEA Results-TE and IWUE Scores
3.4. Tobit Model Results
4. Discussion
5. Conclusions
Author Contributions
Funding
Institutional Review Board Statement
Informed Consent Statement
Data Availability Statement
Acknowledgments
Conflicts of Interest
References
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Abbreviation | Definitions |
---|---|
TE | Technical Efficiency |
DEA | Data Envelopment Analysis |
IWUE | Irrigation Water Use Efficiency |
SFA | Stochastic Frontier Analysis |
DMUs | Decision-Making Units |
CRS | Constant Returns to Scale |
VRS | Variable Returns to Scale |
Variable Name | Explanation | Expected Sign |
---|---|---|
AGE | Age of trees (years) | Negative |
DIS | Distance from the source of irrigated water to farm (m) | Negative |
OWN | Ownership of irrigation system | Positive |
EDU | Education level (dummy variable) | Positive |
EXP | Farmer’s irrigation experience (years) | Positive |
EXT | Extension contact (dummy variable) | Positive |
CRE | Access to credit (dummy variable) | Positive |
Variables | Kinh Group | Indigenous Group | All | |||
---|---|---|---|---|---|---|
Mean | S.D | Mean | S.D | Mean | S.D | |
Age of household head (years) | 44.0 * | 11.0 | 42.0 * | 12.0 | 44.0 | 12.0 |
Education level | 3.0 * | 0.7 | 2.0 * | 0.8 | 2.6 | 0.8 |
Household size (people) | 5.0 * | 1.4 | 6.0 * | 2.2 | 5.0 | 1.7 |
Experience (years) | 18.9 | 6.1 | 20.7 | 6.9 | 19.4 | 6.4 |
Farm size (hectares) | 2.2 | 1.3 | 2.3 | 1.3 | 2.3 | 1.3 |
Irrigation water use (m3) | 4719.6 | 3321.2 | 4766.8 | 3167.7 | 4733.0 | 3270.3 |
Family labor (man-days/ha) | 66 | 43 | 78 | 60 | 69 | 49 |
Working capital (1000 VND/ha) | 55,353.7 * | 40,801.2 | 46,465.2 * | 30,007.2 | 52,833.7 | 38,140.1 |
Coffee productivity (Kg) | 5864.4 | 3487.6 | 5051.1 | 2857.3 | 5633.8 | 3334.2 |
Independent Variable | Coefficient | Std. Err | t-Value | p-Value |
---|---|---|---|---|
Log constant | 4.581 * | 0.690 | 6.63 | 0.059 |
Log working capital | 0.072 ** | 0.038 | 1.90 | 0.005 |
Log labor | 0.175 ** | 0.062 | 2.84 | 0.001 |
Log irrigation water use | 0.163 ** | 0.047 | 3.50 | 0.000 |
Log farm size | 0.536 ** | 0.063 | 8.56 | 0.000 |
R-square | 0.792 | |||
Adjusted R-square | 0.788 | |||
F (4, 189) | 180.24 | |||
Prob > F | 0.0000 | |||
Root MSE | 0.2928 |
Efficiency (%) | TE | |||||
---|---|---|---|---|---|---|
VRS | CRS | |||||
Kinh Group | Indigenous Group | All | Kinh Group | Indigenous Group | All | |
Summary Statistics | ||||||
Mean | 0.76 | 0.81 | 0.72 | 0.67 | 0.75 | 0.66 |
Minimum | 0.31 | 0.30 | 0.24 | 0.21 | 0.29 | 0.21 |
Maximum | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 |
Std. Dev. | 0.18 | 0.19 | 0.19 | 0.18 | 0.19 | 0.18 |
Efficiency Interval | ||||||
100 | 23 (17) | 17 (31) | 21 (11) | 9 (6) | 9 (16) | 16 (8) |
90–100 | 14 (10) | 9 (16) | 24 (12) | 9 (6) | 6 (11.5) | 10 (5) |
80–90 | 27 (19) | 4 (7) | 24 (12) | 15 (11) | 11 (20) | 17 (9) |
70–80 | 16 (12) | 8 (15) | 31 (16) | 20 (14) | 6 (11.5) | 31 (15) |
60–70 | 28 (20) | 9 (16) | 32 (16) | 34 (25) | 9 (16) | 40 (21) |
50–60 | 23 (16) | 6 (11) | 44 (23) | 35 (25) | 9 (16) | 48 (25) |
40–50 | 4 (3) | 1 (2) | 11 (6) | 11 (8) | 4 (7) | 21 (11) |
30–40 | 4 (3) | 0 (0) | 6 (3) | 6 (4) | 0 (0) | 8 (4) |
<30 | 0 (0) | 1 (2) | 1 (1) | 1 (1) | 1 (2) | 3 (2) |
Total | 139 (100) | 55 (100) | 194 (100) | 139 (100) | 55 (100) | 194 (100) |
Efficiency (%) | IWUE | |||||
---|---|---|---|---|---|---|
VRS | CRS | |||||
Kinh Group | Indigenous Group | All | Kinh Group | Indigenous Group | All | |
Summary Statistics | ||||||
Mean | 0.54 | 0.69 | 0.52 | 0.40 | 0.52 | 0.39 |
Minimum | 0.14 | 0.11 | 0.13 | 0.10 | 0.10 | 0.12 |
Maximum | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 |
Std. Dev. | 0.29 | 0.30 | 0.28 | 0.24 | 0.27 | 0.24 |
Efficiency Interval | ||||||
100 | 15 (11) | 14 (25) | 17 (9) | 5 (4) | 6 (11) | 9 (5) |
90–100 | 14 (10) | 7 (13) | 15 (8) | 7 (5) | 3 (5) | 6 (3) |
80–90 | 8 (6) | 5 (9) | 9 (5) | 1 (0) | 0 (0) | 2 (1) |
70–80 | 3 (2) | 1 (2) | 11 (6) | 4 (3) | 3 (5) | 5 (3) |
60–70 | 8 (6) | 4 (7) | 10 (5) | 6 (4) | 8 (15) | 8 (4) |
50–60 | 18 (13) | 6 (11) | 24 (12) | 10 (7) | 6 (11) | 13 (7) |
40–50 | 14 (11) | 4 (7) | 24 (12) | 16 (12) | 7 (13) | 24 (12) |
30–40 | 21 (15) | 9 (16) | 32 (16) | 28 (20) | 8 (15) | 37 (19) |
<30 | 38 (27) | 5 (9) | 52 (27) | 62 (45) | 14 (25) | 90 (46) |
Total | 139 (100) | 55 (100) | 194 (100) | 139 (100) | 55 (100) | 194 (100) |
Variables | Coefficient | Std. Dev | t-Value | p-Value |
---|---|---|---|---|
Intercept | −0.155 NS | 0.116 | −1.34 | 0.183 |
Age of coffee plant (AGE) | 0.002 NS | 0.28 | 0.85 | 0.395 |
Distance to water source (DIS) | −0.00009 * | 0.00003 | −2.56 | 0.011 |
Ownership of irrigation system (OWN) | 0.060 ** | 0.019 | 3.11 | 0.002 |
Education level (EDU) | 0.066 ** | 0.025 | 2.66 | 0.008 |
Experience (EXP) | 0.007 * | 0.003 | 2.31 | 0.022 |
Extension contact (EXT) | 0.123 * | 0.043 | 2.89 | 0.004 |
Access to credit (CRE) | 0.122 * | 0.041 | 2.94 | 0.004 |
Number of observations | 194 | |||
LR chi2 (7) | 59.38 | |||
Prob > chi2 | 0.0000 | |||
Pseudo R2 | 0.3912 |
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Tran, D.N.L.; Nguyen, T.D.; Pham, T.T.; Rañola, R.F., Jr.; Nguyen, T.A. Improving Irrigation Water Use Efficiency of Robusta Coffee (Coffea canephora) Production in Lam Dong Province, Vietnam. Sustainability 2021, 13, 6603. https://doi.org/10.3390/su13126603
Tran DNL, Nguyen TD, Pham TT, Rañola RF Jr., Nguyen TA. Improving Irrigation Water Use Efficiency of Robusta Coffee (Coffea canephora) Production in Lam Dong Province, Vietnam. Sustainability. 2021; 13(12):6603. https://doi.org/10.3390/su13126603
Chicago/Turabian StyleTran, Duyen Nhat Lam, Tien Dinh Nguyen, Thuy Thu Pham, Roberto F. Rañola, Jr., and Thinh An Nguyen. 2021. "Improving Irrigation Water Use Efficiency of Robusta Coffee (Coffea canephora) Production in Lam Dong Province, Vietnam" Sustainability 13, no. 12: 6603. https://doi.org/10.3390/su13126603
APA StyleTran, D. N. L., Nguyen, T. D., Pham, T. T., Rañola, R. F., Jr., & Nguyen, T. A. (2021). Improving Irrigation Water Use Efficiency of Robusta Coffee (Coffea canephora) Production in Lam Dong Province, Vietnam. Sustainability, 13(12), 6603. https://doi.org/10.3390/su13126603