Soil fertility influence on sustainable irrigated rice production in Bangladesh : a precision agriculture approach | |
| Author | Haque, Abu Ahmed Mokammel |
| Call Number | AIT Diss. no.AE-07-06 |
| Subject(s) | Soil fertility--Bangladesh Rice--Soils--Bangladesh Precision farming--Bangladesh |
| Note | A dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy in Agricultural Systems and Engineering, School of Environment, Resources and Development |
| Publisher | Asian Institute of Technology |
| Series Statement | Dissertation ; no. AE-07-06 |
| Abstract | This dissertation research aimed to evaluate the feasibility of optimizing the nutrient management system and to determine the effects of soil fertility on irrigated rice production in Bangladesh. A secondary objective of this research was to conduct resources based optimization analysis of sustainable rice production system in Bangladesh which may have applications in South and South-East Asia. The study was conducted in Trishal sub-district of Bangladesh in 2006 irrigated rice (Boro) season where cropping intensity was >200%; and land-labour was used intensively. The study area was located between 24°32'44" and 24°36'41" North latitude; 90°22'47" and 90°28'45" East longitude; in AEZ 9, Old Brahmaputra Flood Plain which is nearly the central part of Bangladesh. A methodological and analytical frame-work were developed based on system analysis approach considering two HY rice varieties; BR14 and BRRI Dhan 29, three fertilizers effects; Zero, farmer practice (FP), and soil test based (STB), and four conceptual loads; neutral, zero, imbalance and optimum. Geo-referenced 100 FP plots (sampling density 3.22 ha), 10 zero inputs plots and 10 optimum STB inputs plots (sampling density 322 ha) were selected which covered the major component variables of sustainability. Site-specific micro-level resources optimization processes were used by using higher order statistical and GIS analyses. Data-sets were split into three, sub-systems: i) inputs - nutrients from natural resources (land utilization), nutrients from applied organic and inorganic such as fertilizers and manure, nutrients from rain and irrigation water etc.; ii) outputs - nutrient outputs as plant uptake covered harvested grain and straw yield, residual and lost form of nutrients in soil; and iii) economic aspects - using input-output data on nutrients, production related all input costs (labour cost, cost of irrigation water, cost of chemicals and fertilizers, seeds etc.); and output return from yields (grain and straw). Selected different types of variables were statistically analyzed and presented in tables and graphs as effects and interactions of land blocks and land types, while overall values represented as `average effect' of the whole system. For all variables, geo-reference maps were created and management zones were conceptually classified by using graduated gray color scale. Different zones representing variables (i.e. inputs, outputs and economic aspects), temporal variability from lowest to highest inside the system were created under low cost precision agriculture aspect for further use. Research results revealed that irrigated rice production system was influenced by soil clay, SOM and soil N etc. Overall system status indicated very low soil nutrients; possessed very low to low soil total N, soil available P and K, low to medium soil available S and medium status of soil available Zn. The soil properties analyzed before cultivation and after rice harvest (i.e. conceptual neutral load state) revealed their inter-relationships, interactions influencing all other variables at different stages of rice production season in terms of three sub-system component variables. Under conceptual load categories and fertilizers effects, the systems research results indicated that: i) at zero load (i.e. zero fertilization level) condition- SOM played as predictor of yield (R²=0.64); ii) at imbalance load (i.e. FP fertilization level) condition- available soil K, N and S nutrients played as predictor of yield (R²=0.30) even though they were in luxuriant level. Available soil P nutrient was in deficit level and played as yield limiting factor; and iii) at Optimum load (i.e. STB fertilization approach) condition- soil available N nutrient played as predictor of yield (R²=0.59) if other nutrients would be in optimum level. Based on nutrients activities in the system, input (available nutrients) versus output (nutrients for yield partitioning) was plotted as yield performance curve; and whole system input cost versus output return was plotted as economic performance curve. This specific system evaluation process could statistically identify system boundary limits, model curves, best curve fit conditions and some scope and limitations for better system performance such as labour utilization, and small scale mechanization etc. Based on the key sustainability indicators of the system such as economic-production performance, soil resources holding capacity, SNNS potentiality, labour potentiality, nutrient management potential and land degradation, a `system sustainability graph' was developed. Statistically the graph could quantify the system sustainability boundaries for resources optimization, thrust sector identification and system risk minimization for sustainable irrigated rice production. In addition, this study offered a methodology showing quantitative approach for sustainability index estimation based on available nutrient input-outputs and economic aspects for irrigated rice production in Bangladesh |
| Year | 2007 |
| Corresponding Series Added Entry | Asian Institute of Technology. Dissertation ; no. AE-07-06 |
| Type | Dissertation |
| School | School of Environment, Resources, and Development (SERD) |
| Department | Department of Food, Agriculture and Natural Resources (Former title: Department of Food Agriculture, and BioResources (DFAB)) |
| Academic Program/FoS | Agricultural and Food Engineering (AE) |
| Chairperson(s) | Jayasuriya, H. P. W.; |
| Examination Committee(s) | Salokhe, Vilas M.;Thipathi, Nitin K.;Preeda Parkpian; |
| Scholarship Donor(s) | Asian Institute of Technology Fellowship;Protected Cultivation Project; |
| Degree | Thesis (Ph.D.) - Asian Institute of Technology, 2007 |