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Oil palms (OP) produce palm oil, a unique commodity without commercial alternatives. A serious disease of OP is basal stem rot (BSR) caused by Ganoderma boninense Pat. Climate change will likely increase BSR, thereby causing mortality of OP and reduced yields of palm oil. Work is being undertaken to produce modified OP (mOP) to resist BSR, although this will take decades for full development, if successfully produced at all. mOP will not be 100% effective, and it would be useful to know the effect of mOP on the key parameters of BSR incidence, OP mortality, and yield loss. The current paper employed CLIMEX modeling of suitable climates for OP and modeling narratives for Indonesia and Thailand. Indonesia is the largest producer of OP and Thailand is a much smaller manufacturer, and it was informative to compare these two countries. The gains from using mOP were substantial compared to the current production of some other continents and countries. The current paper, for the first time, assessed how climate change will affect BSR parameters for conventional and mOP. Greater consideration of the potential benefits of mOP is required to justify investing in the technology. [ABSTRACT FROM AUTHOR]

To avoid the potential adverse impacts of climate change from global warming, it is suggested that the target of net zero emissions should be reached by this mid-century. Thailand is aiming to achieve carbon neutrality by 2050. Since electricity generation is one of the largest producers of carbon dioxide emission, the associated emissions must be greatly reduced to achieve the targets mentioned above. Thus, new generation expansion plans must be well developed. This paper discusses the development of generation expansion plans considering Thailand's latest policies along with enhancement of the existing multi-period linear programming model, allowing new electricity generation technologies having low emissions, e.g., solar PV with battery and hydrogen blending in natural gas, to be integrated into generation expansion planning. Then, four generation expansion plans with different levels of hydrogen blending in natural gas are proposed and discussed. It is found that Thailand can achieve carbon neutrality by 2050 by promoting more use of renewable energy altogether with trade-off between land for solar PV installation and amount of hydrogen blended in natural gas. The lesson learned from this study provides crucial information about possible pathways to achieve carbon neutrality in the electricity sector for policy makers in other countries. [ABSTRACT FROM AUTHOR]

The Indo-Pacific, a vast biogeographic of Earth, is influenced by both the Indian and East Asian monsoons. Despite its geographical importance, this region has been less studied compared to East Asia and India. Here, we present speleothem records from southern Thailand that cover the last 1500 years, including a hiatus during the Little Ice Age, providing insights into the interactions among climate dynamics, human influences, and ecological responses to climate change. Notably, our records lack the characteristic cold and warm periods observed in other regions, such as the Dark Ages Cold Period and Medieval Warm Period, which may reflect the complexity of the tropical climate system or the region's unique topography. The analysis reveals a link between ENSO multi-decadal variability and hydroclimate conditions in southern Thailand, as evidenced by speleothem δ18O. Furthermore, a comparison between speleothem δ13C and the Normalized Difference Vegetation Index (NDVI) indicates significant vegetation changes in the last three decades, corresponding with increased atmospheric CO2 levels and expansion of agricultural land due to human activities during the Current Warm Period. Additionally, our study suggests that an abrupt increase in sea surface temperatures may enhance vegetation growth in the Indo-Pacific by influencing atmospheric circulation and increasing precipitation. [ABSTRACT FROM AUTHOR]

This study evaluated the impacts of climate change on hydro-meteorological droughts in the Chao Phraya River Basin (CPRB), Thailand under two Representative Concentration Pathway (RCP) scenarios (RCP4.5 and RCP8.5). We used three Reginal Climate Models (RCMs) of the Southeast Asia Regional Climate Downscaling/Coordinated Regional Climate Downscaling Experiment—Southeast Asia (SEACLID/CORDEX-SEA), which are bias corrected. The Soil and Water Assessment Tool (SWAT) was used to simulate streamflow for future periods. The Standardized Precipitation Index (SPI) and Standardized Streamflow Index (SSI) were estimated and used for drought characterization at three time scales (3, 6, and 12 months). The lag time between meteorological and hydrological droughts is approximately 1–3 months. The results suggest that the CPRB is likely to experience less frequent hydro-meteorological drought events in the future. The meteorological drought is projected to be longer, more severe, and intense. The severity of hydrological drought tends to decrease, but the intensity could increase. Climate change has been discovered to alter drought behaviors in the CPRB, posing a threat to drought monitoring and warning because droughts will be less predictable in future climate scenarios. The characterization of historical and future droughts over the CPRB is therefore valuable in developing an improved understanding of the risks of drought. [ABSTRACT FROM AUTHOR]

The sustainability of Indigenous Socioecological Systems (ISES) largely depends on well-crafted policy regulations. In particular, Indigenous traditional food systems (ITFS) are an essential component of ISES that provide a variety of culturally accepted, healthy foods while also playing an important role in cultural, spiritual, and economic value to the Indigenous people (IP). Thus, sustainably managing these traditional natural resources must be a priority. As custodians of much of the world's ecological system, IP have, for generations, exhibited sustainable lifestyles in governing these systems. However, Indigenous perspectives and voices have not been properly reflected in the ISES sustainability discourse, and few comparative case studies have addressed this issue. This study contributes to fill this research gap using a desktop research method based on the Political Ecological Theoretical Framework (PETF) to examine how existing regulatory policies may affect the resilience and sustainability of ISES-ITFS, especially in relation to growing environmental and climatic pressures. Two Indigenous communities, the Karen in Thailand and different Indigenous groups in the Republic of Sakha (Yakutia) in Russia, are examined as case studies. Our study provides crucial insight that should help the development of robust policy interventions that integrate Indigenous concerns into policies and regulations, emphasizing self-determination, cultural preservation, and land rights. The findings emphasize the necessity for comprehensive legal frameworks prioritizing Indigenous involvement and concerns in climate and sustainability policy implementations. The ultimate goal is to foster meaningful dialogues between policymakers and IP in navigating the climate and sustainability challenges of our time. [ABSTRACT FROM AUTHOR]

Simple Summary: Mecoptera, commonly known as scorpionflies and hangingflies, are an interesting, but small, and rarely-observed order of moderately-sized insects, with at least 22 species in Thailand. These insects typically prefer cool, moist mature forested habitats with broken sunlight, often on low vegetation bordering small mountain streams. They are poor fliers thus limiting their ability to disperse. For these reasons, they serve as a valuable bioindicator for monitoring changes in climatic and forest communities. However, no ecological study has previously been conducted for this insect group. This study exploits data from Project Tiger, where specimens were collected using Malaise and pan traps from 18 national parks across Thailand to characterize the biodiversity of Mecoptera with a focus on the influences of elevational and climatic factors. We found 21 species in total with 52% of them being specific to particular regions. Negative correlations between species richness and abundance of Mecoptera with both elevation and temperature were observed, suggesting a predominance of species in mid-altitude areas with a peak in the rainy season (21 species) followed by the hot (10 species) and cold (7 species) seasons. We suggest that the narrow distribution and preference for mid-altitude make Mecoptera particularly vulnerable to global warming, raising urgent conservation concerns. Ecological analyses of the small and lesser-known insect order Mecoptera in Thailand are presented. Specimens were collected monthly over a period of 12 consecutive months, using both Malaise and pan traps, from 29 sampling sites located in 18 national parks throughout Thailand. A total of 21 species in four genera were identified from 797 specimens, including Panorpa (1 species), Neopanorpa (18 species), Bittacus (1 species), and Terrobittacus (1 species), with the latter genus representing a new genus record to Thailand. Neopanorpa harmandi, N. siamensis, N. byersi, and N. malaisei were the most abundant species, representing 27.4%, 11.3%, 10.3% and 8.8% of the total specimens, respectively. The species with the highest frequency, as indicated by the high percentage of species occurrence (%SO), was N. siamensis (51%), followed by N. byersi (34%), N. harmandi (34%), N. spatulata (27%), and N. inchoata (27%). Eleven species (52%) exhibited specific regional occurrences. N. tuberosa and N. siamensis had the widest distribution, being found in almost all regions except for western and southern regions for the first and second species, respectively. The seasonal species richness of Mecoptera was high during the rainy season in the northern, northeastern, central, eastern, and western regions, with the highest richness observed in July (15 species), followed by the hot (10 species) and cold seasons (7 species), while there was no significant difference in species richness between seasons in the southern region. Multiple regression models revealed a negative association between species richness and abundance of Mecoptera with both elevation and temperature, and a positive association between rainfall and species evenness. It is predicted that climatic changes will have a detrimental effect on the mecopteran community. The results of this study enhance the understanding of the ecological aspects of Mecoptera, offering crucial insights into its biodiversity and distribution, which are vital for conservation and forest management. [ABSTRACT FROM AUTHOR]

Groundwater vulnerability has gained widespread attention, particularly in Chiang Mai Province, one of Thailand's fastest-growing cities, which is experiencing rapid development in both economic and social sectors. The expansion of urban communities and the industrial, tourism, and agriculture sectors has resulted in the overutilization of available resources, notably water resources. This overuse, coupled with the adoption of modern technology to boost productivity and meet market demands, has led to an increased reliance on groundwater to supplement surface water sources, providing benefits across all sectors. However, the economic and social growth plays a pivotal role in shaping the diversity of land use, encompassing residential, commercial, industrial, and agricultural activities. These activities, in turn, directly contribute to environmental pollution, particularly in terms of the risk of groundwater contamination in Chiang Mai Province. This study aims to predict the future vulnerabilities of groundwater resources under an ensemble of climate change scenarios and changes in land-use patterns. Chiang Mai Province in northern Thailand is one of the fastest-growing cities and therefore is experiencing rapid urbanization, as well as land-use pattern changes, which was important for the case study. The new DRASTIC model, namely the DRASTIC-LP model, combined with GIS-based techniques and overlay techniques, was used to generate the map of groundwater resource vulnerabilities. A point pollution source (P)-related land-use pattern (L) that represents contamination impacts was considered an additional new DRASTIC parameter. The study's findings reveal the high reliability and maximum effectiveness of the new DRASTIC-LP model in assessing groundwater vulnerability and contamination-risk areas under a climate change scenario (by MIROC-ESM-CHEM model under RCP.8.5 scenario) and land-use pattern changes (by CA_Markov Chian Model) for both the current year (2020) and the next 50-year period (2021–2070). Furthermore, the new DRASTIC-LP model is employed to trace the movement of pollutants from high- to very high-risk areas based on the groundwater vulnerability and contamination-risk maps. The results highlight that waste disposal dumping sites pose a more critical distribution and movement of pollutants when compared to industrial sites. Additionally, unconsolidated aquifers and cracked consolidated rock aquifers show a potentially higher occurrence of pollutant distribution and movement when compared to consolidated aquifers. Consequently, the study's outcomes are applied to formulate guidelines for the management and control of groundwater resource contamination. These guidelines serve as valuable tools for decision makers, aiding in pollution prevention and the effective management of contamination risks in groundwater resources. [ABSTRACT FROM AUTHOR]

This document is a summary of a journal article titled "Impacts of Human Activities and Climate Change on Freshwater Fish—Volume II." The article explores the threats faced by freshwater fish due to human activities and climate change, including changes in land and water use, pollution, invasive species, and climate change. It presents case studies from different regions, covering topics such as the importance of macrophytes for fish diversity, the presence of microplastics in fish gastrointestinal tracts, the effects of atrazine exposure on fish behavior, genetic and morphological variations in barbel species, heat tolerance of Thai river fish species, trophic structure of fish communities in subtropical lakes, habitat suitability of native fish species in Central Anatolia, and factors influencing fish beta diversity and size diversity. The article provides valuable insights into the impacts of human-induced changes on freshwater fish and offers potential solutions for conservation efforts. Additionally, the article discusses a study on the ecology of balitorid fish in Thailand, which found that high ammonia levels and river temperatures negatively affected the occurrence and diversity of balitorid fish, while dissolved silica had a positive influence. The study concluded that balitorid fish are vulnerable to climate change and pollution, and recommended reducing anthropogenic pressure to preserve their freshwater habitat. [Extracted from the article]

Climate change (CC) and land-use change (LUC) will alter a basin's hydrological processes and water balance. Quantifying their significance is imperative in formulating appropriate countermeasures and management plans. This study assesses projected changes in hydrological variables under CC and LUC scenarios to provide multi-dimensional insight into water balance relevant to an agricultural watershed in Northeast Thailand. The soil and water assessment tool (SWAT) is utilized to simulate hydrological variables (evapotranspiration, soil moisture, surface runoff, and water yield) for the baseline (1981–2010) and the near-future (2021–2050) after calibrating the model. CC projections considering the CMIP6 model ensemble for the high-emission scenario (SSP5-8.5) show the annual rainfall may not change significantly (0.5% increase compared to baseline). However, the surface runoff will likely increase by 33% due to the projected increase in rainfall intensity and extremes. The increase in urban areas due to LUC for the business as usual (BAU) scenario is also expected to boost surface runoff by 38–87%. Similarly, the LUC scenario with forest expansion will increase evapotranspiration by up to 1.3%. While CC is anticipated to raise water yield by 11%, LUC may reduce it by 6%. Under the combined scenario, the yield is expected to increase by 8%, indicating CC as the dominating driver. The results show that although CC governs the runoff from the basin, land-use change will also impact flows at a monthly scale. Importantly, soil moisture in the future will decrease (8–9%) under both stressors, which will reverberate in the basin's agricultural livelihood and socioeconomic settings unless the appropriate adaptation measures are implemented. [ABSTRACT FROM AUTHOR]

Bruguiera gymnorhiza (L.) Savigny is one of the most important and widespread mangrove species in the Indo-West Pacific region. Here, the population structure and genetic diversity of B. gymnorhiza along the coastlines of Thailand were examined. A total of 73 B. gymnorhiza accessions in 15 provinces were sequenced using RAD-seq to generate their SNPs. Based on the high-quality SNPs, the topology of the maximum likelihood phylogenetic tree clearly presented two genetically distinct groups corresponding to two geographic regions, the Gulf of Thailand and the Andaman Sea coasts. The results for the population structure provided by STRUCTURE and PCA also showed two main genetic clusters and their genetic admixture. A moderate genetic diversity was observed among the accessions, with average observed and expected heterozygosity values of 0.397 and 0.317, respectively. A high genetic differentiation (FST = 0.16, p < 0.001) between the two subpopulations was significantly found. An analysis of molecular variance revealed 83.95% of the genetic variation within populations and 16.05% of the genetic variation among populations. A high genetic variation within the populations and admixture may facilitate adaptation to local environments and climate changes. These results provide important information on the population genetic structure and genetic diversity of B. gymnorhiza in Thailand for further mangrove management. [ABSTRACT FROM AUTHOR]

To narrow the gap of agricultural water insufficiency in the Lam Takong River Basin, Thailand, we conducted an assessment of water availability and agricultural water demand under climate and land use changes. The water availability was estimated by SWAT, which was calibrated and validated during 2008–2012 and 2013–2018 against the observed daily discharge at the M.164 station. Measured and simulated discharges showed good agreement during calibration and validation, as indicated by values of 0.75 and 0.69 for R2 and 0.74 and 0.63 for Nash–Sutcliffe Efficiency, respectively. The results of GCMs (IPSL-CM5-MR, NorESM1-M, and CanESM2) under RCPs 4.5 and 8.5 were calculated to investigate changes in rainfall and temperature during 2020–2099. The warming tendencies of future maximum and minimum temperatures were projected as 0.018 and 0.022 °C/year and 0.038 and 0.045 °C/year under RCPs 4.5 and 8.5, respectively. The future rainfall was found to increase by 0.34 and 1.06 mm/year under RCPs 4.5 and 8.5, respectively. As compared to the 2017 baseline, the future planted areas of rice, maize, and cassava were projected to decrease during 2020–2099, while the sugarcane plantation area was expected to increase until 2079 and then decline. The top three greatest increases in future land use area were identified as residential and built-up land (in 2099), water bodies (in 2099), and other agricultural land (in 2059), while the three largest decrease rates were paddy fields (in 2099), forest land (in 2099), and orchards (during 2059–2079). Under the increased reservoir storage and future climate and land use changes, the maximum and minimum increases in annual discharge were 1.4 (RCP 8.5) and 0.1 million m3 (RCP 4.5) during 2060–2079. The sugarcane water demand calculated by CROPWAT was solely projected to increase from baseline to 2099 under RCP 4.5, while the increase for sugarcane and cassava was found for RCP 8.5. The future unmet water demand was found to increase under RCPs 4.5 and 8.5, and the highest deficits would take place in June and March during 2020–2039 and 2040–2099, respectively. In this context, it is remarkable that the obtained results are able to capture the continued and growing imbalance between water supply and agricultural demand exacerbated by future climatic and anthropogenic land use changes. This research contributes new insight for compiling a comprehensive set of actions to effectively build resilience and ensure future water sufficiency in the Lam Takong River Basin. [ABSTRACT FROM AUTHOR]

Species of Paramyrothecium that are reported as plant pathogens and cause leaf spot or leaf blight have been reported on many commercial crops worldwide. In 2019, during a survey of fungi causing leaf spots on plants in Chiang Mai and Mae Hong Son provinces, northern Thailand, 16 isolates from 14 host species across nine plant families were collected. A new species Paramyrothecium vignicola sp. nov. was identified based on morphology and concatenated (ITS, cmdA, rpb2, and tub2) phylogeny. Further, P. breviseta and P. foliicola represented novel geographic records to Thailand, while P. eichhorniae represented a novel host record (Psophocarpus sp., Centrosema sp., Aristolochia sp.). These species were confirmed to be the causal agents of the leaf spot disease through pathogenicity assay. Furthermore, cross pathogenicity tests on Coffea arabica L., Commelina benghalensis L., Glycine max (L.) Merr., and Dieffenbachia seguine (Jacq.) Schott revealed multiple host ranges for these pathogens. Further research is required into the host–pathogen relationship of Paramyrothecium species that cause leaf spot and their management. Biotic and abiotic stresses caused by climate change may affect plant health and disease susceptibility. Hence, proper identification and monitoring of fungal communities in the environment are important to understand emerging diseases and for implementation of disease management strategies. [ABSTRACT FROM AUTHOR]

The draft post-2020 Global Biodiversity Framework asks CBD parties to conserve at least 30% of the planet by 2030 'through a well-connected and effective system of protected areas ... with the focus on areas particularly important for biodiversity'. We use Thailand as a case study for the ability of a densely populated, hyper diverse, tropical, middle-income country to meet this target at a national level. Existing protected areas (PAs) total 24.3% of Thailand's land area. Adding forest on government land adjacent to existing PAs, plus unprotected areas of Ramsar sites, raises this to 29.5%. To assess the importance for biodiversity, we used modeled distributions of birds and mammals plus, as proxies for other biodiversity components, elevation, bioclimate, forest type, and WWF ecoregion. All modeled species occur in the current PA system but <30% meet representation targets. Expansion of the system increases the proportion of mammals and birds adequately protected and increases the protection for underrepresented bioclimatic zones and forest types. The expanded system remains fragmented and underrepresents key habitats, but opportunities for increasing protection of these are limited. It is also still vulnerable to climate change, although projected impacts are reduced. Additional protection is needed for wetland and coastal habitats, and limestone karsts. [ABSTRACT FROM AUTHOR]

Indigenous upland rice (Oryza sativa L.) is an important staple food for people. The productivity of upland rice is generally lower than lowland rice since crop yield depends on the amount of rainfall. Climate change is a major problem in rice production due to the unpredictable rainfall. The flowering time, maturity days, growth duration, and photoperiod sensitivity in rice are important for determining productivity. Therefore, in this study, indigenous upland rice germplasm was classified according to their flowering-related traits in the basic vegetative phase (BVP), photoperiod sensitivity index (PSI), grain yield (GY), and yield components. The results reveal that the BVP ranges from 12 to 76 days (mainly less than 30 days) while the PSI ranges from −0.14 to 0.89. Classification of the three groups was based on the PSI: 24 insensitivities (G1; PSI = −0.14–0.30), 214 weakly sensitive (G2; PSI = 0.31–0.70), and 63 strongly sensitive (G3; PSI = 0.71–0.89). Grain yield showed different correlations with day to flowering (DTF), PSI, and BVP in each group. The results suggest that the selection criteria were not only based on GY and DTF but also PSI and BVP. The new ideotypes for upland rice selection under unpredictable conditions such as rainfall and light duration are weakly sensitive (PSI range 0.30–0.60), low BVP (20–30 days), and less than 105 days of DTF, such as ULR189, ULR039, ULR036, ULR403, ULR364, ULR342, and ULR245 genotypes. [ABSTRACT FROM AUTHOR]

The carbon storage value of forest restoration, by the framework species method (FSM) in northern Thailand, was assessed for trees (using a partial harvesting technique) and soil and compared with restoration costs. Forest carbon accumulation amounted to 143.08 tC/ha in trees and 8.56 tC/ha in soil over 14 years, with a combined value of USD 27,173.63 (net present value (NPV), discounted at 2.85%/year)) (at the current European carbon credit (EUA) price of 55.98 EUR/tCO2 = 242.21 USD/tC). Restoration costs increased from 2190.27 to 5680.72 USD/ha with declining pre-existing natural regeneration or 3.99–10.34 USD per ton of sequestered CO2. Profits over 14 years ranged in NPV from 22,215.45 to 25,157.04 USD/ha, breaking even from just over 4 years to just under 7, respectively. In contrast, profits from maize cultivation (a major regional deforestation driver) averaged 96.25 USD/ha/year, or just 1347.53 USD/ha over 14 years. Consequently, forest restoration could become a financially attractive alternative land use, provided an open, transparent, carbon market is created. Therefore, this study supports creation of a forest-carbon trading system in Thailand, to incentivize forest restoration and fire prevention, increase farmers' incomes, reduce smoke-related public health problems, protect watersheds, and conserve biodiversity. [ABSTRACT FROM AUTHOR]

Calcifying macroalgae contribute significantly to the structure and function of tropical marine ecosystems. Their calcification and photosynthetic processes are not well understood despite their critical role in marine carbon cycles and high vulnerability to environmental changes. This study aims to provide a better understanding of the macroalgal calcification process, focusing on its relevance concerning seawater carbonate chemistry and its relationship to photosynthesis in three dominant calcified macroalgae in Thailand, Padina boryana, Halimeda macroloba and Halimeda opuntia. Morphological and microstructural attributes of the three macroalgae were analyzed and subsequently linked to their calcification rates and responses to inhibition of photosynthesis. In the first experiment, seawater pH, total alkalinity and total dissolved inorganic carbon were measured after incubation of the macroalgae in the light and after equilibration of the seawater with air. Estimations of carbon uptake into photosynthesis and calcification and carbon release into air were obtained thereafter. Our results provide evidence that calcification of the three calcified macroalgae is a potential source of CO2, where calcification by H. opuntia and H. macroloba leads to a greater release of CO2 per biomass weight than P. boryana. Nevertheless, this capacity is expected to vary on a diurnal basis, as the second experiment indicates that calcification is highly coupled to photosynthetic activity. Lower pH as a result of inhibited photosynthesis under darkness imposes more negative effects on H. opuntia and H. macroloba than on P. boryana, implying that they are more sensitive to acidification. These effects were worsened when photosynthesis was inhibited by 3-(3,4-dichlorophenyl)-1,1-dimethylurea, highlighting the significance of photosynthetic electron transport-dependent processes. Our findings suggest that estimations of the amount of carbon stored in the vegetated marine ecosystems should account for macroalgal calcification as a potential carbon source while considering diurnal variations in photosynthesis and seawater pH in a natural setting. [ABSTRACT FROM AUTHOR]