Farmers' adaptation to rainfall variability and salinity in embankment and non-embankment areas of the lower Ayeyarwaddy Delta, Myanmar | |
| Author | Seinn Seinn Mu |
| Call Number | AIT Diss. no.RD-16-02 |
| Subject(s) | Salinity--Myanmar Embankment--Myanmar |
| Note | A dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy in Regional and Rural Development Planning |
| Publisher | Asian Institute of Technology |
| Series Statement | Dissertation ; no. RD-16-02 |
| Abstract | The alterations of rainfall pattern and incre asing sea level rise pose significant threats to the agriculture sector of Ayeyarwaddy Delta , where a griculture and fishery are the major livelihoods of its inhabitants . Apart from climate change, d ense population, degradation of mangrove forests and mono cropping of rice have negatively impacted d elta ecosystem. Agriculture, which accounts for 26 % of the total GDP, is central to Myanmar’s economy and is also highly vulnerable to climate change. Boosting the national rice yield by hybrid rice growing prog rams and expansion of irrigated area have been the principal driver s for improper land utilization with heavy use of chemical fertilizer. S ummer rice growing is the short - term coping way of increasing farm income but , on the long term, it cannot maintain t he production in a sustainable manner. T his study has attempted to assess the farmers’ adaptation in existing agricultural system of the embankment (EMB) and non - embankment (NEMB) areas of Ayeyarwaddy D elta focus ing on two areas: i) the impacts of rain fal l variability and salinity on crop ping system and crop variety use between 1993 to 2013 ; and ii) factors influencing on adoption of agricultural adaptation practices and the effect of adaptation on farm income . The study draws o n both primary and secondar y data sources related to crop production, land utilization, sea water intrusion and salinity, climate data of rainfall, temperature and adaptation practices. Primary data was collected through a survey among 240 rice farming households where the 135 house holds come from the NEMB area and the remaining 105 households from the EMB area of Labutta, lower Ayeyarwaddy Delta . Several analytical tools were employed in this study such as the non - parametric test (chi square) , t - test of means, Analysis of Variance ( ANOVA), Weighted Average Index (WAI), Benefit - Cost analysis and M ultivariate P robit model (MVP) . The results indicate that the increasing trend in precipitation is prominent and 17 times of positively deviated years during 1993 - 2013 . The major causes of s alinity in the d elta region were sea level rise and the seasonal tidal regime. In the d elta area, the mean tidal level as well as the spring tide level fluctuates seasonally. Sp ring tides are highest in summer season leading t o strong seasonal salinization . Consequently, t he rice growing are as in the d elta are not completely protected against a periodic saltwater intrusion even in rainy season . Depending on different geographical location, agricultural adaptation practices adopted by farmers vary . In the NE MB area , it was mainly constrained and unprotected by inflow of saline water in the summer season, making farmers more vulnerable . With this, farmers in the NEMB area applied a higher number of adaptation practices to respond better t o salinity. Findings of the study suggest that t he most common adaptation initiatives in the NEMB area were transplanting, salt tolerant varieties, application of compost, intermittent flooding and short - lived rice varieties as adopted by 74%, 68 %, 59 %, 48 % and 46 % of the farmers, respectively. Likewise, in the EMB area, the use of short - lived rice varieties, shifting from direct seeding to transplanting, application of compost and manure and salt - tolerant rice varieties were commonly adopted by 72 %, 67 %, 53 % and 46 % of the farmers, respectively. A multivariate probit model was used to estimate the simultaneous interdependent decisions by the farm households to explain the factors influencing the adaptation of rice farmers ’ response towards rainfall variability and salin ity. Irrespective of correlation signs,the most significant determinants in adaptations of NEMB area are farm size, farm income, non - farm income, training and lowland followed by educational level, family agricultural labor, land ownership, farming experi ence and the institutional credit. On the hand , in the EMB area, five variables out of 12 were found to be most influential on the adoption of agricultural adaptation practices, namely, farm size, farm income, training frequency, credit and existing of ver y lowland soil. Changing the adapted cropping system from conventional cropping could increase the income of farmers in both areas. In the EMB area, the net income provided from combination of monsoon rice and vegetables per hectare ( 800 to 1200 USD ) is re latively higher than conventional cropping sys tem of rice - fallow (226.4 USD). In both areas, adapted cropping system with rice and vegetables can increase the benefit - cost ratio of NEMB farmers from 1.70 to 2.0 and that of EMB farmers from 1.8 to 2.13. L ikewise , the higher profit from short - lived, aromatic and salt tolerant rice suggests that these varieties are not only resilient in salinity and rainfall variability but it is economically adapted as well. Notably, c ultivating aromatic rice from long - live d rice could increase the benefit - cost ratio from 1.52 to 1.92 in the EMB area and 1.57 to 1.68 in the NEMB area. Cultivating salt tolerant rice from long - lived rice could increase the benefit - cost ratio from 1.52 to 1.79 in the EMB area and 1.57 to 1.82 i n the EMB area. Thus, it estimated that cultivating aromatic rice in EMB area is as profitable as cultivating salt tolerant rice in NEMB area after short - lived rice. Apart from crop variety selection , farmers can facilitate rainfall variability and salini ty by combining cultural, soil and water management practices. In case of portfolio adaptation, inte gration of adaptation practices and s upportive infrastructure are possible attributes for higher productivity of rice. The poor linkage of extension and tra ining programs are reflective of po or lowland soil condition and cultural practices. Although double cropping of rice in monsoon and summer has provided higher cropping intensity and farm income, this has contributed to soil salinity and environmental unsu stainability. Policy instruments are therefore suggested for an effective impl ementation of soil conservation , initiation of improved adaptable rice varieties , and integrated cropping system in lowland rainfed rice - based cropping system of Ayeyarwaddy Delta. |
| Year | 2016 |
| Corresponding Series Added Entry | Asian Institute of Technology. Dissertation ; no. RD-16-02 |
| Type | Dissertation |
| School | School of Environment, Resources, and Development (SERD) |
| Department | Department of Development and Sustainability (DDS) |
| Academic Program/FoS | Rural Development, Gender and Resources (RD) |
| Chairperson(s) | Ahmad,Mokbul Morshed |
| Examination Committee(s) | Shrestha, Rajendra Prasad ;Thapa, Gopal Bahadur |
| Scholarship Donor(s) | Ministry of Foreign Affairs, Norway |
| Degree | Thesis (Ph. D.) - Asian Institute of Technology, 2016 |