Impacts of CFC/FAO/ICRISAT Livelihood Improvement project in Asia Region II Thailand

This is a report on the impact assessment survey, which was done as part of the CFC/FAO/ICRISAT project entitled Enhanced Utilization of Sorghum and Pearl Millet Grains in Poultry Feed Industry to Improve Livelihoods of Smallscale Farmers in Asia. The project was implemented from May 2005 to March 2009 in the sorghum growing area of Thailand, both in white sorghum planting area (Suphan Buri and Kanchanaburi) and the red sorghum planting area (Nakhon Sawan and Lopburi). A detailed final survey was conducted through questionnaires. All information contained herein is based on the interviews and questionnaires, and therefore reflects the views of the respondents. The respondents who participated in the project were interviewed and the cost of sorghum production was recorded. Respondents outside the project area were similarly interviewed for comparison

Vulnerability to Climate Change: Adaptation Strategies and Layers of Resilience - Quantifying Vulnerability to Climate Change in Thailand. Research Report No. 9

The main objective of vulnerability analysis is to understand the extent to which the system is susceptible to the sustaining damage from climate change. The analysis was carried out based on the different sets of socio-economic variables using the standard IPCC methodology. The northeastern region of Thailand is highly vulnerable compared to the other regions. Further, the provincial vulnerability mapping for the northeastern region was also undertaken. This study was done as a precursor to the micro/household analysis on exposure, sensitivity and adaptive capacity

Mainstreaming Grassroots Level Adaptation and Building Climate Resilient Agriculture in Thailand

Climate change is becoming severe and has had a negative impact on agriculture and farmers’ livelihoods in Thailand. The climate change impacts on crop yield possibly leads to food insecurity globally. Scientists have projected a major climate change in the middle of the 21st century (2045-2065). The average monthly maximum temperature in Thailand is expected to increase by 3-4ºC and monthly minimum temperature is expected to increase by more than 4ºC throughout the country (Chinvanno 2010). The regions, ie, the Northeast, Central and the Northern, received less than 1,200 mm annual rainfall (1970-2005) and it is the driest area of the country. Agriculture in Thailand is already impacted by frequent drought or dry spells, flood, unpredictable rainfall and heat waves

Comparative analysis of different tillage systems used in sugarcane (Thailand)

In order to reduce the impact of decreasing profit margins in crop production systems, all possible options that will increase net profits need to be explored. Land preparation and stool removal in sugarcane production can be a major contributor to overall production costs. Since estimates that mechanization can contribute as much as 50% of the total production costs, considerable savings can potentially be made if the number of tillage operations is reduced. Such savings however, have to be offset against other costs associated with minimum or no-tillage systems, such as the increased need for herbicide. In addition, conventional tillage systems have been implicated in yield decline over the long-term and therefore yield benefits are envisaged, together with cost savings, by the adoption of minimum and no-tillage sugarcane production. A comparative analysis of five sugarcane tillage systems using data from eight years, showed that minimum tillage, with mechanical stool removal and machine planting gave the best economic returns, being 29.3 and 39.4% more profitable than the conventional and no-tillage treatments, respectively. Other minimum tillage treatments, with sub-soiling and machine / manual planting combinations also performed well. Whilst the no-tillage treatment made substantial savings from the non-use of machinery, these were offset to a large degree by the extra costs associated with herbicide use and extra labour requirements

Fate of urea nitrogen applied to a banana crop in the wet tropics of Queensland

This paper reports a study in the wet tropics of Queensland on the fate of urea applied to a dry or wet soil surface under banana plants. The transformations of urea were followed in cylindrical microplots (10.3 cm diameter x 23 cm long), a nitrogen (N) balance was conducted in macroplots (3.85 m x 2.0 m) with N-15 labelled urea, and ammonia volatilization was determined with a mass balance micrometeorological method. Most of the urea was hydrolysed within 4 days irrespective of whether the urea was applied onto dry or wet soil. The nitrification rate was slow at the beginning when the soil was dry, but increased greatly after small amounts of rain; in the 9 days after rain 20% of the N applied was converted to nitrate. In the 40 days between urea application and harvesting, the macroplots the banana plants absorbed only 15% of the applied N; at harvest the largest amounts were found in the leaves (3.4%), pseudostem (3.3%) and fruit (2.8%). Only 1% of the applied N was present in the roots. Sixty percent of the applied N was recovered in the soil and 25% was lost from the plant-soil system by either ammonia volatilization, leaching or denitrification. Direct measurements of ammonia volatilization showed that when urea was applied to dry soil, and only small amounts of rain were received, little ammonia was lost (3.2% of applied N). In contrast, when urea was applied onto wet soil, urea hydrolysis occurred immediately, ammonia was volatilized on day zero, and 17.2% of the applied N was lost by the ninth day after that application. In the latter study, although rain fell every day, the extensive canopy of banana plants reduced the rainfall reaching the fertilized area under the bananas to less than half. Thus even though 90 mm of rain fell during the volatilization study, the fertilized area did not receive sufficient water to wash the urea into the soil and prevent ammonia loss. Losses by leaching and denitrification combined amounted to 5% of the applied N

Significance of gaseous nitrogen loss from a tropical dairy pasture fertilised with urea

This paper reports a study in the wet tropics of Queensland on the fate of urea applied to a dairy pasture in the absence of grazing animals. A nitrogen balance was conducted in cylindrical plots with N-15-labelled urea, and ammonia volatilisation was determined using a mass balance micrometeorological method. The pasture plants took up 42% of the applied nitrogen in the 98 days between fertiliser application and harvest. At harvest 18% of the applied nitrogen was found in the soil, and 40% was lost from the plant-soil system. The micrometeorological study showed that 20% of the unrecovered nitrogen was lost by ammonia volatilisation. As there was no evidence for leaching or runoff losses it was concluded that the remaining 20% of the applied nitrogen was lost by denitrification. It is evident from these results that fertiliser nitrogen is not being used efficiently on dairy pastures, and that practices need to be changed to conserve fertiliser nitrogen and reduce contamination of the environment

Effect of fertilizer placement on nitrogen loss from sugarcane in tropical Queensland

This paper reports on the fate of nitrogen (N) in a first ratoon sugarcane (Saccharum officinarum L.) crop in the wet tropics of Queensland when urea was either surface applied or drilled into the soil 3–4 days after harvesting the plant cane. Ammonia volatilization was measured with a micrometeorological method, and fertilizer N recovery in plants and soil, to a depth of 140 cm, was determined by mass balance in macroplots with 15N labelled urea 166 and 334 days after fertilizer application. The bulk of the fertilizer and soil N uptake by the sugarcane occurred between fertilizing and the first sampling on day 166. Nitrogen use efficiency measured as the recovery of labelled N in the plant was very low. At the time of the final sampling (day 334), the efficiencies for the surface and subsurface treatments were 18.9% and 28.8%, respectively. The tops, leaves, stalks and roots in the subsurface treatment contained significantly more fertilizer N than the corresponding parts in the surface treatment. The total recoveries of fertilizer N for the plant-trash-soil system on day 334 indicate significant losses of N in both treatments (59.1% and 45.6% of the applied N in the surface and subsurface treatments, respectively). Drilling the urea into the soil instead of applying it to the trash surface reduced ammonia loss from 37.3% to 5.5% of the applied N. Subtracting the data for ammonia loss from total loss suggests that losses by leaching and denitrification combined increased from 21.8% and 40.1% of the applied N as a result of the change in method of application. While the treatment resulted in increased denitrification and/or leaching loss, total N loss was reduced from 59.1% to 45.6%, (a saving of 13.5% of the applied N), which resulted in an extra 9.9%of the applied N being assimilated by the crop

The availability of nitrogen from sugarcane trash on contrasting soils in the wet tropics of North Queensland

Sugarcane crop residues ('trash') have the potential to supply nitrogen (N) to crops when they are retained on the soil surface after harvest. Farmers should account for the contribution of this N to crop requirements in order to avoid over-fertilisation. In very wet tropical locations, the climate may increase the rate of trash decomposition as well as the amount of N lost from the soil-plant system due to leaching or denitrification. A field experiment was conducted on Hydrosol and Ferrosol soils in the wet tropics of northern Australia using N-15-labelled trash either applied to the soil surface or incorporated. Labelled urea fertiliser was also applied with unlabelled surface trash. The objective of the experiment was to investigate the contribution of trash to crop N nutrition in wet tropical climates, the timing of N mineralisation from trash, and the retention of trash N in contrasting soils. Less than 6% of the N in trash was recovered in the first crop and the recovery was not affected by trash incorporation. Around 6% of the N in fertiliser was also recovered in the first crop, which was less than previously measured in temperate areas (20-40%). Leaf samples taken at the end of the second crop contined 2-3% of N from trash and fertilizer applied at the beginning of the experiment. Although most N was recovered in the 0-1.5 m soil layer there was some evidence of movement of N below this depth. The results showed that trash supplies N slowly and in small amounts to the succeeding crop in wet tropics sugarcane growing areas regardless of trash placement (on the soil surface or incorporated) or soil type, and so N mineralisation from a single trash blanket is not important for sugarcane production in the wet tropics