Impact assessment of land use change on the future rice production vulnerability in Deli Serdang Regency, Indonesia | |
| Author | Siagian, Deddy Romulo |
| Call Number | AIT Diss. no.NR-19-05 |
| Subject(s) | Land use--Indonesia Crops and climate--Indonesia Rice farming--Environmental aspects--Indonesia |
| Note | A dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy in Natural Resources Management, School of Environment, Resources and Development |
| Publisher | Asian Institute of Technology |
| Series Statement | Dissertation ; no. NR-19-05 |
| Abstract | The land use change is largely an anthropogenic phenomenon which may occur directly and indirectly at the global, regional, and local level at different rate and trend. Deli Serdang Regency, which is located in North Sumatera Province, Indonesia, is one of the regencies that produce the highest rice production and productivity. The total rice land area in the regency has decreased over time as it is converted to other land uses due to population growth, urban development, plantation expansion, and the inappropriate policies. Consequently, the regency is high vulnerability to loosing its all rice land and no rice production. It is important to protect main rice land areas from the future rice production point of view besides the rice land being one important ecosystem. The objectives of the study were to i) map out the land uses between 1989 to 2018 and investigate land use changes, ii) determine the significant factors of riceland change among biophysical and socio-economic factors, iii) simulate future land use changes under three different scenarios and iv) investigate the future rice production vulnerability under three different scenarios. The study employs a multidisciplinary approach by integrating the GIS and remote sensing technology, field and household-based survey, statistical analysis, land use modelling, and vulnerability analysis. The primary data were collected from field survey, soil analysis, and household-based survey, while the secondary data, such as the demographic and other statistical data were collected from the Statistical Institution of Deli Serdang Regency. The land use change was investigated by classifying the satellite images acquired for the years 1989,1994,2003,2009, and 2018 and overlaying in GIS. The factors affecting land use change, especially riceland area, were determined by combining the GIS and remote sensing together with statistical analysis (i.e. normalization and weight analysis, PCA, binary logistic regression) of the data collected from field and household-based survey. The Dyna-CLUE model was used to project the future land use by 2040 for three scenarios (Business as Usual or BAU, Potential Riceland Protection or PRP and Conservation- Oriented or CO). The vulnerability analysis was performed for each simulated-land use to investigate rice production vulnerability at the district level by considering the rice production and consumption data for the future. The forest and riceland were the predominant land uses in 1989, representing 35% and 34% of the total area, respectively but in 2018, the plantation became the predominant land use which covered 32% of the total area as forest and riceland had continuously decreased since 1989. The largest plantation expansion which replaced forest and riceland has occurred in the period of2009 to 2018 by 19,187 ha and 19,787 ha, respectively. The urban areas also gradually increased by more than three-fold in this period. The forest and riceland were converted by urban development by 2,640 ha and 10,782 ha, respectively. Among the biophysical and socio-economic variables as the factors of land use change, in particular to rice land area, the elevation, slope, distance to road, distance to stream, distance to the district capital, distance to the provincial capital, population density, and potential land were the significant biophysical factors. While family size, the inadequacy of water, off- farm income, frequency of flood and lack of awareness on resource degradation were the significant socio-economic factors. In terms of land use modelling, the result of the BAU scenario revealed that the plantation and urban continuously increased, which covered 44% and 15%, respectively in 2040. The majority of urban development took place near to the regency and provincial capitals. The riceland was drastically decreased, near to 40%, from 2018 to 2040. Meanwhile, the PRP scenario showed promising option to protect riceland and to increase its total area amounting to 31 % of the study area. Controlling the plantation expansion and urban development and together with implementing the spatial policy to protect potential riceland were the strategies for this achievement. For the CO scenario, the plantation and forest were the predominant land use in 2040, which covered 40% and 21 %, respectively. Unfortunately, the total area of riceland in this scenario is smaller than the total area of rice land in 2018, which is decreased by 32%. The expected output of CO scenario is to maintain the conservation zones, which is the majority covered by forest and mangrove. The milled rice production vulnerability analysis showed that the BAU scenario generated the worst possible occurrence in 2040 compare with the two scenarios. Out of 18 districts, 16 districts fell into severely vulnerable category in terms of rice production. The CO scenario showed a better result than the BAU scenario as there were only 14 districts in the severely vulnerable level category, and six districts will have a surplus in milled rice production. The total milled rice production from these both scenarios, BAU and CO scenarios, could not fulfil the milled rice consumption by 2040. The reasons behind this result were due to the loss of riceland caused by conversion issue and influenced by the total number of population. Meanwhile, the PRP scenario generated the best output, by resulting only 3 out of 9 shortage-districts categorized at the severely vulnerable. Also, there were 13 districts with a surplus milled rice production. Based on this scenario, a total of 516,091 tons of milled rice production can fulfil the milled rice consumption in 2040. However, implementation ofthe PRP scenario in the real world situation to anticipate future rice production vulnerability is not easy and simple. It needs collaboration of several stakeholders including local and high level governments, non-government organization, farmers, university/research institutions, insurance agencies, bank. In addition, it should be supported by some strategic actions to balance the social, economic and environmental aspects, such as by increasing the capacity building of farmers, by controlling the population growth, by stabilizing the farm price, by providing insurance to compensate the impact of climate change and environmental disasters, by protecting the potential riceland, by controlling the rate expansion of plantation and locating on the appropriate zone, by protecting the conservation zone and by constructing and developing an irrigation system and water catchment. |
| Year | 2019 |
| Corresponding Series Added Entry | Asian Institute of Technology. Dissertation ; no. NR-19-05 |
| Type | Dissertation |
| School | School of Environment, Resources, and Development (SERD) |
| Department | Department of Development and Sustainability (DDS) |
| Academic Program/FoS | Natural Resources Management (NRM) |
| Chairperson(s) | Shrestha, Rajendra Prasad |
| Examination Committee(s) | Shrestha, Sangam;Kuwornu, John K.M. |
| Scholarship Donor(s) | Indonesian Agency for Agricultural Research and Development (IAARD);Asian Institute of Technology Fellowship |
| Degree | Thesis (Ph.D.) - Asian Institute of Technology, 2019 |