Season In Thailand Research Articles

Electrical resistivity tomography (ERT) exploration data in drought prone areas case study: Buriram Province, Thailand

An electrical resistivity tomography (ERT) investigation was conducted across four drought-prone districts in the Buriram Province, Thailand. The primary objective was to evaluate and map the potential of groundwater reservoirs as sources of water for household and agricultural purposes during the dry season. It was accomplished through the implementation of the Schlumberger array configuration. An electrical resistivity survey instrument was used to generate a 2D resistivity model of the electrical resistance profiles, or pseudo section profiles. The survey instrument included more than 50 electrodes, enabling the investigation of the profile to a depth of up to 50 m from the ground surface. The resistivity values obtained from the field data were recorded and converted or interpreted using RES2DINV software. The data were analysed by comparing them with the geological information about the site and referencing the geological borehole data as at 50 m depth from the surface. The results of the ERT survey indicated that groundwater in the arid areas of the Buriram Province can be found at shallow depths around 10–20 m from the surface and it is deposited in sedimentary and clay layers, and it has remained relatively stable over a 2-year period with the water level measured by an electric probe in the summer, winter and rainy seasons in Thailand.

Regional-scale flood impacts on a small mountainous catchment in Thailand under a changing climate

Abstract Extreme rainfall and flooding are common during the summer monsoon season in Thailand. In this study, we utilized Robust Empirical Quantile Mapping (RQUANT) to correct the bias in precipitation, and total runoff data obtained from the latest Couple Model Intercomparison Project phase 6 (CMIP6) for the upper Lam Takong river basin. Five different methods were employed to estimate the river discharge and four estimations based on Budyko functions. Our analysis revealed that the ‘Total runoff’ method yielded the most accurate representation of the observed discharge. Impacts of change in land use are examined in terms of compound roughness. The Multi-Model Ensemble (MME) precipitation under medium-emission (SSP2-4.5) and high-emission (SSP5-8.5) scenarios is projected to increase by 5.74 and 10.91%, respectively. Correspondingly, the discharges are expected to increase by 4.57 and 11.05% for the far-future periods. In general, the Flo-2D model satisfactorily simulated the water level in the main channel but it underestimated small inundation depth (<0.5 m) across the floodplain. Comparing inundation maps among different scenarios and timelines, changes in the inundation area were relatively small (0.05%), especially when compared to changes in floodplain storage (6.85%) due to the mountainous nature of the river basin.

Simultaneous Confidence Intervals for the Ratios of the Means of Zero-Inflated Gamma Distributions and Its Application

Heavy rain in September (the middle of the rainy season in Thailand) can cause unexpected events and natural disasters such as flooding in many areas of the country. Rainfall series that contain both zero and positive values belong to the zero-inflated gamma distribution, which combines the binomial and gamma distributions. Precipitation in various areas of a country can be estimated by using simultaneous confidence intervals (CIs) for the ratios of the means of multiple zero-inflated gamma populations. Herein, we propose six simultaneous CIs constructed using the fiducial generalized CI method, Bayesian and highest posterior density (HPD) interval methods based on the Jeffreys’rule or uniform prior, and method of variance estimates recovery (MOVER). The performances of the proposed simultaneous CI methods were evaluated using a Monte Carlo simulation in terms of the coverage probabilities and expected lengths. The results from a comparative simulation study show that the HPD interval based on the Jeffreys’rule prior performed the best in most cases, while in some situations, the fiducial generalized CI performed well. All of the methods were applied to estimate the simultaneous CIs for the ratios of the means of natural rainfall data from six regions in Thailand.

Mushroom poisoning in Thailand between 2003 and 2017.

The frequent occurrence of mushroom poisoning cases in the wet season in Thailand has long been recognized but has never been quantitatively analyzed. This study aims to analyze mushroom poisoning cases in Thailand between 2003 and 2017 and focused on their association with the rainfall. The results revealed 22,571 cases and 106 deaths in this period. Cases were higher for females than males, adults than children, and agriculturists than people in other occupations. Cases were higher in the northeastern and northern regions than in the central, south, and east regions. There are strong effects of seasonality on mushroom poisoning cases. Over the 15-y period, 17,337 cases occurred in the wet season (May-Sep) compared with 5,234 cases in the dry season (Oct-Apr). The number of monthly poisoning cases were high in men, mature adults, agriculturists, people living in the rural areas and people living in the Northeastern and Northern provinces. Moreover, a strong positive correlation was shown between the number of monthly poisoning cases and the amount of monthly rainfall.

Semen production capacity among boar breeds and effect of organic antioxidant supplementation on sperm characteristics during the hot season in Thailand

Semen production capacity among boar breeds and effect of organic antioxidant supplementation on sperm characteristics during the hot season in Thailand

Investigation of kidney function changes in sea salt workers during harvest season in Thailand.

Occupational factors have previously been mentioned as contributing to decreased kidney function and the development of chronic kidney disease of unknown cause. Sea salt workers are one of the occupations facing high outdoor temperatures and a highly, intensive workload. The purpose of the study was to examine whether the kidney function of sea salt workers at the beginning of the harvest season differs from kidney function at the end of the harvest season and to identify factors that can predict the change of kidney function. Data were collected from salt workers (n=50) who were between 18–60 years of age without hypertension, diabetes, and kidney disease in Samut Sakhon province, Thailand. Urine specific gravity (USG) was used for hydration status and the estimated glomerular filter rate (eGFR) was used to measure kidney function. The mixed model was used to find differences over the harvest season and prediction of factors. On average, the eGFR was estimated to decrease by 15.2 ml/min/1.73 m2 over the harvest season. The decline in eGFR of sea salt workers with moderate and heavy workloads were significantly faster than their light workload counterparts after controlling for other covariates. Similarly, dehydration (USG ≥ 1.030) significantly accelerated the rate of kidney function loss. Our study confirmed exposure to heat over the harvest season leads to decreased eGFR in sea salt workers. The rate of change of eGFR could be predicted by workload and hydration status. Workers with dehydration who performed medium to heavy workloads in farms showed faster kidney function decline than those who performed light workload.

Characteristics, sources, and health risks of ambient nanoparticles (PM0.1) bound metal in Bangkok, Thailand

The objective of this study was to characterize ambient nanoparticles (PM 0.1 )-bound metals in Bangkok, Thailand and assess the health risks of these materials to human. A year-long sampling campaign was conducted between November 2014 and October 2015. The PM 0.1 mass concentration ranged from 10 to 27 μg/m 3 , and the average PM 0.1 mass concentration was 15 ± 2 μg/m 3 . The total concentration of the thirteen elements was 345 ± 31 ng/m 3 , with Fe, K, Na, Al, Cu, Mg, and Zn (>10 ng/m 3 ) being the dominant species. The highest total element concentration occurred in the cold dry season followed by the hot dry and wet seasons. A principal component analysis (PCA) indicated that the primary sources of PM 0.1 were derived from road traffic, the industrial sector, and biomass burning. The high concentrations of metals found in the cold dry season suggest that PM 0.1 -bound metal derived from road traffic and biomass burning from neighboring areas were transported to Bangkok. High level of K indicates that biomass burning was a major source during cold dry season. Total cancer risk from all the carcinogenic elements was 5.84 × 10 −6 in adults, which does not exceed the upper limit of the acceptable risk assessment range. The findings of this study provide further clarification of the emission source profile and the pattern of PM 0.1 particles and should be of value for emission control and mitigation of PM emission in an urban area. • The PM 0.1 fraction as a function of the season in Thailand examined in detail. • Sources of PM 0.1 were traffic, industry, and biomass fires. • The level of PM 0.1 during haze pollution is increased substantially. • Carcinogenic risk is assessed to be tolerable.

Quantitative Evaluation of Macro-Nutrient Uptake by Cassava in a Tropical Savanna Climate

Matching fertilization with crop needs is important for maximizing yields and reducing fertilizer losses. Seasonal variation in nutrient uptake dynamics is poorly understood and thus, the ability to optimize fertilization strategies is limited. This study aims to investigate the effects of planting dates on macronutrient uptake dynamics in cassava genotypes with full irrigation. The performance of cassava genotypes, i.e., CMR38-125-77, Kasetsart 50 and Rayong 11, were evaluated in the early rainy (ERS) and post rainy seasons (PRS) for two years using a randomized complete block design with four replicates. The plants were harvested at 1, 3, 6, 9 and 12 months. Planting dates had significant effects on the accumulation of dry matter and storage roots as well as nutrient uptakes and partitioning. On average, the total nutrient uptake per plant to produce 2831–3279 g of biomass with 1244–1810 g of storage roots in the ERS varied among cassava genotypes, ranging from 21.1–24.3 g N, 5.1–5.9 g P, 26.5–29.5 g K, 14.1–22.2 g Ca, 6.1–7.6 g Mg and 2.0–2.3 g S. The total nutrient uptake per plant to produce 3353–3824 g of biomass with 1604–2253 g of storage roots in the PRS ranged from 27.1–32.4 g N, 5.2–6.0 g P, 29.1–31.3 g K, 11.9–20.3 g Ca, 7.3–9.9 g Mg and 1.2–1.5 g S. In the ERS, the majority of the total nutrient uptake occurred at the early growth stages, whereas in the PRS, this occurred at the mid- to late growth stages. At final harvest, the percentages of nutrient removal by the storage roots for ERS were 24.7–36.0% N, 26.0–32.3% P, 43.4–51.5% K, 12.4–17.6% Ca, 22.2–31.5% Mg and 27.2–31.5% S, whereas in the PRS the percentages were 30.4–44.4% N, 33.3–41.6% P, 44.7–57.3% K, 12.0–15.1% Ca, 20.2–28.1% Mg and 12.0–25.4% S. CMR38-125-77 exhibited satisfactory performance in nutrient uptake, nutrient use efficiency and storage roots yield across the planting dates. The evidence obtained from this study would greatly facilitate more efficient adoption of precision agriculture in cassava production by applying recommended fertilizers, e.g., rates, kinds and timings, according to crop demand in each growing season in Thailand and for choosing superior cassava genotypes.

Phallus chiangmaiensis sp. nov. and a Record of P. merulinus in Thailand

During the rainy season in Thailand, specimens of Phallus chiangmaiensis sp. nov. and P. merulinus were collected from Chiang Mai and Samut Sakhon Provinces, respectively. Molecular phylogenetic analyses based on sequences of the nuclear ribosomal large subunit (LSU), nuclear ribosomal 5.8S gene including the internal transcribed spacer regions 1 and 2 (ITS), and the protein-coding gene atp6 (mitochondrial adenosine triphosphate [ATP] synthase subunit 6) support the placement of the new species within Phallus. Phallus chiangmaiensis has a well-developed white indusium and campanulated caps with reticulate surfaces. It differs morphologically from the related species, as supported by the phylogenetic data. Phallus merulinus is reported here as a species that was re-encountered in Thailand. The descriptions of the species are accompanied by illustrations of macro- and micro- morphological features, and a discussion of the related taxa is presented.

Changing Land Use and Population Density Are Degrading Water Quality in the Lower Mekong Basin

Establishing reference conditions in rivers is important to understand environmental change and protect ecosystem integrity. Ranked third globally for fish biodiversity, the Mekong River has the world’s largest inland fishery providing livelihoods, food security, and protein to the local population. It is therefore of paramount importance to maintain the water quality and biotic integrity of this ecosystem. We analyzed land use impacts on water quality constituents (TSS, TN, TP, DO, NO3−, NH4+, PO43−) in the Lower Mekong Basin. We then used a best-model regression approach with anthropogenic land-use as independent variables and water quality parameters as the dependent variables, to define reference conditions in the absence of human activities (corresponding to the intercept value). From 2000–2017, the population and the percentage of crop, rice, and plantation land cover increased, while there was a decrease in upland forest and flooded forest. Agriculture, urbanization, and population density were associated with decreasing water quality health in the Lower Mekong Basin. In several sites, Thailand and Laos had higher TN, NO3−, and NH4+ concentrations compared to reference conditions, while Cambodia had higher TP values than reference conditions, showing water quality degradation. TSS was higher than reference conditions in the dry season in Cambodia, but was lower than reference values in the wet season in Thailand and Laos. This study shows how deforestation from agriculture conversion and increasing urbanization pressure causes water quality decline in the Lower Mekong Basin, and provides a first characterization of reference water quality conditions for the Lower Mekong River and its tributaries.

Temperature profiles and electric energy consumption for wood/Poly(vinyl chloride) composite and fibre cement board houses

Temperature profiles of wood/poly(vinyl chloride) (WPVC) and fibre cement board (FCB) were studied under solar exposure for houses constructed at the same time. Wall temperatures of WPVC and FCB houses during both day-time and night-time were compared for three different seasons in Thailand, with and without air conditioning. Electric energy consumption (EEC) for the houses was also estimated for energy saving purpose. The temperature profiles indicate that during the winter season, the maximum exterior temperatures of WPVC and FCB houses under solar exposure moved from east to south and from west to north during the day-time while the maximum temperature was obtained at the southern direction. As expected, the differences in temperature between the exterior and interior walls with air conditioning were larger than without air conditioning. In the summer season, the maximum temperatures of WPVC and FCB houses moved from east to west and from north to south while the maximum temperature appeared at the eastern wall. For the rainy season, the temperature profile results including the effects of air conditioning and materials were more similar to those of the summer season. For all seasons, the exterior-interior temperature differences of WPVC house were larger than those of FCB house, regardless of the effects of air conditioning and direction, the maximum temperature differences (ΔT) between WPVC and FCB walls were 6.78 °C for winter season, 8.92 °C for summer season, and 6.72 °C for rainy season. This suggested that the WPVC material exhibited highly potential use as better housing insulator as compared with the FCB material. The EEC values clearly indicated that the WPVC house was more economical than the FCB house by 22–26%.

Heat Stress, Physiological Response, and Heat-Related Symptoms among Thai Sugarcane Workers.

Prolonged or intense exposure to heat can lead to a range of health effects. This study investigated heat exposure and heat-related symptoms which sugarcane workers (90 sugarcane cutters and 93 factory workers) experienced during a harvesting season in Thailand. During the hottest month of harvesting season, wet bulb globe temperature was collected in the work environment, and workloads observed, to assess heat stress. Urine samples for dehydration test, blood pressure, heart rate, and body temperature were measured pre- and post-shift to measure heat strain. Fluid intake and heat-related symptoms which subjects had experienced during the harvesting season were gathered via interviews at the end of the season. From the results, sugarcane cutters showed high risk for heat stress and strain, unlike factory workers who had low risk based on the American Conference of Governmental Industrial Hygiene (ACGIH) threshold limit values (TLVs) for heat stress. Dehydration was observed among sugarcane cutters and significant physiological changes including heart rate, body temperature, and systolic blood pressure occurred across the work shift. Significantly more sugarcane cutters reported experiencing heat-related symptoms including weakness/fatigue, heavy sweating, headache, rash, muscle cramp, dry mouth, dizziness, fever, dry/cracking skin, and swelling, compared to sugarcane factory workers. We conclude that the heat stress experienced by sugarcane cutters working in extremely hot environments, with high workloads, is associated with acute health effects. Preventive and control measures for heat stress are needed to reduce the risk of heat strain.

Enterovirus infections in pediatric patients hospitalized with acute gastroenteritis in Chiang Mai, Thailand, 2015-2018.

BackgroundInfection with viruses especially rotavirus, norovirus, astrovirus, and adenovirus has been known to be a major cause of acute gastroenteritis in children under 5 years of age globally, particularly in developing countries. Also, some genotypes of enteroviruses (EVs) have been reported to be associated with gastroenteritis. This study is aimed to investigate the prevalence and genotype diversity of EV in children admitted to hospitals with acute gastroenteritis.MethodsA total of 1,736 fecal specimens were collected from children hospitalized with diarrhea in Chiang Mai, Thailand from 2015 to 2018. All specimens were tested for the presence of EV by RT-PCR of the 5′ untranslated region. The genotypes of EV were further identified by nucleotide sequencing and phylogenetic analysis of the viral protein 1 (VP1) gene.ResultsEV was detected in 154 out of 1,736 specimens (8.9%) throughout the study period. The prevalence of EV detected in 2015, 2016, 2017, and 2018 was 7.2%, 9.0%, 11.2%, and 8.6%, respectively. EV was detected all year round with a high prevalence during rainy season in Thailand. Overall, 37 genotypes of EV were identified in this study. Among these, coxsackievirus (CV)-A24 and CV-B5 (7.5% each), and EV-C96 (6.8%) were the common genotypes detected.ConclusionThis study demonstrates the prevalence, seasonal distribution, and genotype diversity of EV circulating in children hospitalized with acute gastroenteritis in Chiang Mai, Thailand during the period 2015 to 2018.

Backcross breeding for improvement of heat tolerance at reproductive phase in Thai rice (Oryza sativaL.) varieties

AbstractHeat stress during the reproductive and grain-filling stages leads to severe yield losses in rice, especially in irrigated areas during the dry season in Thailand. Thus, breeding for heat-tolerant rice is one of the strategies for developing rice crops adapted to the effects of high temperature in major growing regions. M9962, a fast neutron-induced mutant, was identified as a heat-tolerant line that was then used as a donor parent and crossed with the Phisanulok 2 (PSL2) cultivar (the recurrent parent) in a backcross breeding programme. Heat tolerance scoring under controlled greenhouse and field conditions was based on the percentage of spikelet fertility. Yield trials for the BC2F7and BC3F6lines were subsequently conducted under field conditions at three locations and under controlled greenhouse conditions during the dry season of 2019 (DS2019). In the early generation, 210 plants of the BC1F1population and 440 plants of BC2F1population were evaluated for their heat tolerance, and the spikelet fertility distribution within the BC1F1, BC2F1and BC3F1populations showed a skewed-right pattern. In addition, most rice plants in every generation were heat sensitive. Finally, compared with PSL2, the four-candidate heat-tolerant lines exhibited a high percentage of spikelet fertility and high yield. In addition, the one candidate line, BC2F7-6-5-4-1-1-21 was most similar to PSL2 in terms of genetic background, plant type and grain quality. Thus, backcross breeding programmes via the spikelet fertility can be used as an indirect trait to select for heat tolerance.

Effect of planting pattern and season on some agronomic performances and yield of sweet potato cv. Japanese Orange

Sweet potato (Ipomoea batatas (L.) is one of the most important root crops in the world. It is primarily grown as a second crop during the dry season in Thailand. Several cultivars are produced with some being imported from Japan, especially cv. Japanese Orange, Yellow and Purple which are popular because they have high value and are rich in phytochemicals. Thai farmers use only one planting pattern for production although there are five recommended patterns available. The objectives of this study were to investigate the effect of different planting patterns on yield, agronomic traits, and determine associations among agronomic traits of sweet potato cv. Japanese Orange. The experiments were conducted during the rainy and dry seasons of 2017. An RCBD with 5 planting patterns and 3 replications were used. Tuber yield, no. of tuber/plant, no. of tuber/ha, no. branch/plant, tuber diameter and tuber fresh weight were measured. The results revealed that during the rainy season, pattern 5 (three vines per hole) had highest tuber yield (11.2 ton/ha), no. of tubers/plant (7.7) and number of tubers/ha (408.9×103) whereas pattern 3 (one vine) had highest no of branches/plant (4.7) and tuber diameter (36.9 mm). In the dry season, patterns 1, 5 and 3 had the highest yields (7.13, 6.71 and 6.48 ton/ha, respectively) pattern 1 had significantly higher tuber fresh weight (84.17 g) than the other four patterns. Pattern 5 had the highest number of tubers/plant and number of tubers/ha during the dry season. We found positive correlations between tuber yield and number of tuber per plant, number of tuber per ha, vine length, vine girth, number of nodes per plant at 60 and 75 DAP.

Time series modeling of pneumonia admissions and its association with air pollution and climate variables in Chiang Mai Province, Thailand

This study aimed to predict the number of pneumonia cases in Chiang Mai Province. An autoregressive integrated moving average (ARIMA) was used in data fitting and to predict future pneumonia cases monthly. Total pneumonia cases of 67,583 were recorded in Chiang Mai during 2003–2014 that the monthly pattern of case was similar every year. Monthly pneumonia cases were increased during February and September, which are the periods of winter and rainy season in Thailand and decreased during April to July (the period of summer season to early rainy season). Using available data on 12 years of pneumonia cases, air pollution, and climate in Chiang Mai, the optimum ARIMA model was investigated based on several conditions. Seasonal change was included in the models due to statistically strong season conditions. Twelve ARIMA model (ARMODEL1–ARMODEL12) scenarios were investigated. Results showed that the most appropriate model was ARIMA (1,0,2)(2,0,0)[12] with PM10 (ARMODEL5) exhibiting the lowest AIC of − 38.29. The predicted number of monthly pneumonia cases by using ARMODEL5 during January to March 2013 was 727, 707, and 658 cases, while the real number was 804, 868, and 783 cases, respectively. This finding indicated that PM10 held the most important role to predict monthly pneumonia cases in Chiang Mai, and the model was able to predict future pneumonia cases in Chiang Mai accurately.

Application of nonwoven as a bunch cover for banana during winter season in Thailand

Application of nonwoven as a bunch cover for banana during winter season in Thailand

The onset and withdrawal of the rainy season in Thailand and their effects on oyster farming

Oyster farming is among the main economic activities in eastern Thailand. The timing of when to harvest and to seed the new mollusk larvae is determined by the salinity of the river, which in turn depends on the influence of the monsoon. The harvest has to be carried out before a mass of fresh water flows down the river in July. The farmers seed the larvae for the next year’s products in December. Global warming potentially extends and intensifies the rainy season, disrupting the harvest cycle and harming oyster products. This research attempts to predict when the rainy season will end by looking at the relationship between the onset of the season in May and the withdrawal in October. Based on statistical analysis, years with an early onset have a late withdrawal, and years with a late onset have an early withdrawal. This knowledge can help farmers decide when to seed the mollusk larvae, and is a useful adaptation tool in dealing with the effects of global warming.

Genetic parameters for resistance against Flavobacterium columnare in Nile tilapia Oreochromis niloticus (Linnaeus, 1758).

Columnaris disease is a major cause of mortality in tilapia hatcheries and commonly occurs during the summer season in Thailand. One way of reducing the problem is by selective breeding for increased disease resistance. The objective of this study was to estimate quantitative genetic parameters for resistance against columnaris in the Chitralada 4 strain of Nile tilapia. Data from 43 full-sib families (2,580 records) of fry (age=32±4days post-hatch) were used in the analyses. Initially, fry were subjected to bath challenge with Flavobacterium columnare (LD50 concentration=1.2×106 CFU/ml) for 14 days. Disease resistance was defined as the number of days from challenge until death (DD) or as a binary trait (dead/alive) on day 14. Linear animal and sire-dam models were used for DD, while threshold animal, threshold sire-dam, binary linear animal and binary linear sire-dam models were used for binary outcomes. Covariate effect of age, fixed effect of challenge day and random effects of the individual animals or sires and dams were included in the models. Mean survival was 32.4±11.6%, and survival rates of the best and poorest families were 70% and 8%, respectively. The highest estimate of heritability (0.30±0.025) was obtained under the threshold sire-dam model. Heritability estimates for DD (0.16±0.034 and 0.17±0.046) were comparable to those obtained from the threshold animal (0.15±0.031) and the binary linear (0.14±0.045 and 0.15±0.044) models. The linear animal and sire-dam models for DD and the threshold sire-dam models performed equally with similar values of rEBV (0.629, 0.628 and 0.627) and accuracy of selection (0.793, 0.793 and 0.791). This study reveals the potential of selective breeding to increase disease resistance to F.columnare in the studied population of Nile tilapia.

Effect of Temperature on Increasing Biogas Production from Sugar Industrial Wastewater Treatment by UASB Process in Pilot Scale

An UASB system is anaerobic wastewater treatment that produces biogas with low operation cost. The main problem of this process is operating at temperatures below 25OC which occurs in the winter season in Thailand. The aim of this work was to improve the efficiency of UASB system by mixing water condensate from electrical power plant with sugar influent before delivery to UASB reactor. The optimized temperature was investigated. The result shows the efficiency of VFA and COD removal was obtained ca. 92% with temperature at 29-40°C. The maximum methane production (0.38 m3CH4/kgCOD) has higher than design parameters about 27.51% at 40OC. The methane production is reduced when the operating temperature is higher than 40OC. Furthermore, the UASB could be considered for decreasing LPG cost in sugar refinery process.