Biodiversity and Species Distribution patterns in the low land of Yuanjiang Dry-Hot Valley
Feng-Chun Yang, Jing‐Xin Liu, Huaping Huang, Jian-Yong Gou, Li Ye, Xian Chen, Huiting Wen, Kritana Prueksakorn, Hong Anh Thi Nguyen, Chaya Sarathchandra
2022
Yuanjiang dry-hot valley is poorly vegetated as a fragile arid ecosystem. Although it was lushly forested in the past, it becomes a tropical montane savannah in recent decades. This study focus on the regime driving such a change which could help to understand the relationship between plants and their living environments in the low land of dry-hot valley, and also help to thrive the ecology policy in Yuanjiang-Red River. Plant species and their individuals are investigated in transects and plots arranging along the river channel. The first is L-transect lying along the river running direction while the second is P-transect lying perpendicular to river channel. Alpha and beta indices are employed to cope with biodiversity change in species and in environments. Expected species, rarity and abundance indices are subscribed to the correlation among species, population size, and their living circumstances, in the terms of Species_estimated, Singeltons, Uniques, ACE, ICE, and Chao2. Meanwhile, fifty years’ meteorological records in the valley including temperature and precipitation are collected for environmental references. The results indicate that: (1) in Yuanjiang dry-hot valley, alpha diversity is higher in the transects and plots closing to river channel than apart from while beta diversity increases from upper stream to the lower with Bray-Curtis < 0.500, but this condition is reversed in the transect perpendicular to the river; (2) tidal range contributes a lot in alpha biodiversity especially in the upper stream; (3) expected species, rarity and abundance indices are stronger in the sites closing to river channel and tidal range which is strongly indicating heterogeneous habitats. (4) Solanum virginianum is an ideal environmental indicator in the dry-hot valley. Conclusively, plants are not flourished in the low altitude ascribed to high temperature and poor precipitation. More attention should be laid on the micro habitat protection in our environmental management.
Evaluation of CMIP6 GCMs for simulations of temperature over Thailand and nearby areas in the early 21st century
Suchada Kamworapan, Phạm Thị Bích Thảo, Shabbir H. Gheewala, Sittichai Pimonsree, Kritana Prueksakorn
Heliyon · 2021
This study evaluates the performance of 13 global climate models (GCMs) from the Coupled Model Intercomparison Project Phase 6 (CMIP6) for simulating the temperature over Thailand during 2000-2014, for land-only, sea-only, and both land and sea. Both observation and reanalysis datasets are employed to compare with the GCMs, evaluated by five performance metrics including mean annual temperature, mean bias errors, mean seasonal cycle amplitude, correlation coefficient, and root mean square error. GCMs are ranked by relative error of all performance metrics. Results show that the temperatures from most GCM simulations are below the mean reference data (i.e., average of ground-based and reanalysis datasets), with north to south gradient in the range from 19 °C to 33 °C. In addition, all the GCM biases range from -0.07 °C to 2.78 °C and show severity of the temperature changes in spatial pattern ranging from -5 °C to 15 °C. The correlations of most GCMs range from 0.70 to 0.95, while the magnitudes of error are less than 2 °C. Study cases point out that the 13-MODEL ENSEMBLE, CESM2, and CNRM-CM6-1 perform better than the other models in simulating the temperature over Thailand for land-only and sea-only, and both land and sea cases, respectively, while MIROC6 performs the worst for all study cases in this study area. From the designed methodology, CNRM-CM6-1 has the best performance and is the most appropriate choice to simulate the temperature for the overall Thailand area.
How fern and fern allies respond to heterogeneous habitat — a case in Yuanjiang dry-hot valley
Fengchun Yang, Chaya Sarathchandra, Jing‐Xin Liu, Huaping Huang, Jian-Yong Gou, Ye Li, Xiao-Ye Mao, Huiting Wen, Zhao Jun, Ming-Fu Yang, Suthathong Homya, Kritana Prueksakorn
Communicative & Integrative Biology · 2021
The Yuanjiang dry-hot valley features hot and dry climate, low vegetation and soil degradation. It had lush vegetation in the past, but has become degraded in recent decades. Understanding the interrelationship between species and the habitat is necessary to explain this change. In this study, a link between fern and fern allies – a group that is hypersensitive to environmental factors and their circumstances is constructed. Intensive transects and plots were designed to be proxies for extant fern and fern allies, and their habitats. Fifty years of meteorological records of precipitation and temperature along altitude and river running direction (latitudinal) were employed. Alpha and beta diversity are used to access diversity. Species_estimated, Singletons, Uniques, ACE, ICE, and Chao2, which associate to abundance and rarity, are subscribed to the correlation between fern and fern allies, and their ecosystem. Eight species, Selaginella pseudopaleifera, Aleuritopteris squamosa, Adiantum malesianum, Pteris vittata, Davallia trichomanoides, Sinephropteris delavayi, Selaginella jugorum, and Lygodium japonicum are used as indicators of a typical xeric and sun-drying habitat. The results indicate (1) accompanied by dramatically shrinking habitats, fern and fern allies are in very low diversity and abundance, whereas the rarity is relatively high; (2) for fern and fern allies, environmental factors are positive when altitude goes up; and (3) eight indicator species are latitudinally correlated with fern and fern allies along the river running direction.
Indoor Air Quality Improvement by Simple Ventilated Practice and Sansevieria Trifasciata
Kanittha Pamonpol, Thanita Areerob, Kritana Prueksakorn
Atmosphere · 2020
Optimum thermal comfort and good indoor air quality (IAQ) is important for occupants. In tropical region offices, an air conditioner is indispensable due to extreme high temperatures. However, the poor ventilation causes health issues. Therefore, the purpose of this study was to propose an improving IAQ method with low energy consumption. Temperature, relative humidity, and CO2 and CO concentration were monitored in a poorly ventilated office for one year to observe seasonal variation. The results showed that the maximum CO2 concentration was above the recommended level for comfort. Simple ventilated practices and placing a number of Sansevieria trifasciata (S. trifasciata) plants were applied to improve the IAQ with the focus on decreasing CO2 concentration as well as achieving energy saving. Reductions of 19.9%, 22.5%, and 58.2% of the CO2 concentration were achieved by ventilation through the door during lunchtime, morning, and full working period, respectively. Placing S. trifasciata in the office could reduce the CO2 concentration by 10.47%–19.29%. A computer simulation was created to observe the efficiency of simple practices to find the optimum conditions. An electricity cost saving of 24.3% was projected for the most feasible option with a consequent reduction in global warming potential, which also resulted in improved IAQ.
Application of multi-monitoring methods to investigate the contamination levels and dispersion of Pb and Zn from tin mining in coastal sediments at Saphan Hin, Phuket, Thailand
Avirut Puttiwongrak, Thongchai Suteerasak, Phuong Khanh, Kiyota Hashimoto, Jorge Carlos Gonzalez, Rawee Rattanakom, Kritana Prueksakorn
Journal of Cleaner Production · 2019
Assessment of heavy metals in sediment at saphan hin, phuket
Akkajit Pensirim, Kaimook Jaileak, Thongchai Suteersak, Kritana Prueksakorn
DOAJ (DOAJ: Directory of Open Access Journals) · 2018
This study was conducted to assess the level of metal pollution in sediment samples at two different locations at Saphan Hin, which received water from Bang-Yai canal. The total content of Tin (Sn), Lead (Pb), and Zinc (Zn) were measured using inductively coupled plasma optical emission spectrometer (ICP-OES) by aqua regia digestion. The ranges of metal concentration (mg kg-1) were 9.04 - 32.17 mg kg-1 and 6.33 - 36.52 mg kg-1 of Pb in Core A and B; and 32.83 - 68.49 mg kg-1 and 21.63 - 73.59 mg kg-1 of Zn in Core A and B, which is below the Sediment Quality Guidelines of Threshold Effects Concentration (TEC) (35.8 mg Pb kg-1 and 121 mg Zn kg-1). Sn was not detected (< 0.03 mg kg-1). Analysis of the geo-accumulation index (Igeo) clearly indicated that most of the analysed sediment samples were not contaminated with the studied metals since low Igeo values were observed (Igeo Pb and Igeo Zn < 0). The detected enrichment factor (EFPb) values between2.0 and 6.0 indicated moderate enrichment, while most of the sediments had EFZn values below 2 which exhibited deficiency to minimal enrichment. The EF values in this study (EF > 1.5) indicates a significant portion of the trace metals was delivered from non-crustal materials and that may be delivered by other sources. Correlation analysis showed positive relationships between Pb and Zn in both cores (r = 0.5** Core A and 0.941** Core B). The association of Pb and Zn is possibly because they originated from the same sources. The determination of other metals should be considered further.