Carbon flow and management in regional rice production in Thailand

This research aims to study the Carbon (C) flow, stock and management in rice production system, including rice cultivation, rice processing and management of rice by-products. The study boundaries are the rice production systems of four districts in Phayao province and the assessment technique is Material Flow Analysis (MFA). The results show that there was a positive C stock each year from large input of biomass residue. However, C loss from soil respiration still was very high because of the long fallow period. Straw was plowed back to the soil and tilled just a few days before flooding time causing high methane emissions at the beginning of cultivation. The recommendations for technology and management practices include harvesting straw for composting and returning the compost to soil, plowing the rest of the straw back to soil more than 30 days before the flooding period, accepting crop rotation practice instead of leaving the land fallow and finally, setting up a gasification or pyrolysis plant using straw to produce energy and by-product of bio-char for farmer to return it back to the soil. Applying feed-in-tariff or incentives like C-credit for reducing methane and C-credit for increasing C stock in the soil are also recommended

An integrated decision support tool for more sustainable management of biomass resources in agricultural regions

Agriculture currently faces a number of environmental sustainability issues. Three key issues that are the focus of this study are greenhouse gas emissions, depletion of mineral phosphorus resources and cadmium contamination in agricultural soil. Biomass can potentially be used as a renewable energy source and can also be returned to improve the nutrient and drainage structure of agricultural soils. Sustainable management of biomass and agriculture can have significant impacts on reducing greenhouse gas emissions from a region. Moreover, it reduces the demand for external energy supply, phosphorous (P) based fertilizer, and its associated Cadmium (Cd) impurity which can contaminate the soil, plant and food chains. These three issues have typically been considered separately, and managed by different agencies or organisations. The aim of this thesis is to develop an integrated decision support tool that can be used for evaluating alternative options for management and resource recovery from biomass for enhancing recovery of energy, returning carbon (C) and phosphorus (P) from biomass back to soil, reducing greenhouse gas emissions and also cadmium (Cd) contamination in an agricultural region. This research employed a combination of the tools of Material Flow Analysis (MFA), Geographic Information System (GIS) and Cost-Benefit Analysis (CBA). MFA is used as the primary tool for this research. GIS and CBA are combined with MFA in later stages of the overall procedure to develop an integrated decision support tool.This integrated tool has been applied to the Murrumbidgee Irrigation Area (MIA) in Australia. Tracking the flow of essential substances using MFA has identified current resource management efficiency and substances accumulation across the region. Integrating a spatial analysis tool (GIS) with MFA has provided a feedback driven monitoring tool for evaluating trends of spatial accumulation of substances on agricultural land. This enables the time remaining before acceptable limits are exceeded to be estimated on a spatial basis. Integrated MFA and CBA has been applied to evaluate the tradeoffs and potential synergies of alternative biomass management options. Overall the tool can assist in evaluating the effectiveness of alternative scenarios and visualise the results to stakeholders in a systematic way

Measuring sustainability performance of rice cultivation in Thailand using Sustainable Rice Platform indicators

The sustainability level of current rice farming practices in Thailand was assessed based on in-field data from interviewing 2000 farmers covering six rice varieties and their different production systems. Data were collected on farmers’ characteristics and farming activities according to the 41 requirements of the Sustainable Rice Platform (SRP) standard. The SRP scores ranged from 53 to 81%, with the best performance by Khao Dawk Mali 105 cultivated in rainfed, organic production systems. The key success factors were linked to the formation of a farmer group resulting in very good performance on farm management, Integrated Pest Management, health and safety, and water use. The proposed 12 performance indicators (PIs) interconnected with the 41 requirements are considered appropriate to measure and monitor progress toward sustainable rice cultivation for policy makers. PIs for good governance, affordability of living costs, energy-use efficiency, and life satisfaction could potentially be added, considering the local context in relation to sustainable agriculture goals. The successful cases of SRP-certified rice farms and the benefits from SRP implementation should be conveyed to with other rice farmers to induce wider implementation. The SRP scores and PIs were useful to identify areas requiring priority interventions to make progress toward sustainability