Estimating greenhouse gas fluxes from constructed wetlands used for water quality improvement

Methane (CH4 ), nitrous oxide (N2O) and carbon dioxide (CO2 ) fluxes were evaluated from constructed wetlands (CWs) used to improve domestic wastewater quality. Experiments employed subsurface flow (SF) and free water surface flow (FWS) CWs planted with Cyperus spp. Results showed seasonal fluctuations of greenhouse gas fluxes. Greenhouse gas fluxes from SF-CWs and FWS-CWS were significantly different (p<0.05) while pollutant removal efficiencies of both CWs were not significantly different. The average CH4 , N2O and CO2 fluxes from SF-CWs were 2.9±3.5, 1.0±1.7, and 15.2±12.3 mg/m2 /hr, respectively, corresponding to the average global warming potential (GWP) of 392 mg CO2 equivalents/m2 /hr. For FWS-CWs, the average CH4 , N2O and CO2 fluxes were 5.9±4.8, 1.8±1.0, and 29.6±20.2 mg/m2 /hr, respectively, having an average GWP of 698 mg CO2 equivalents/m2 /hr. Thus, FWS-CWs have a higher GWP than SF-CWs when they were used as a system for domestic water improvement

Seasonal and Land Use Effects on Amphibian Abundance and Species Richness in the Sakaerat Biosphere Reserve, Thailand

Habitat destruction and degradation in the tropics have led to a dramatic increase in altered habitats. Understanding the impacts of these disturbed areas on biodiversity will be critical to future conservation efforts. Despite heavy deforestation, Southeast Asia is underrepresented in studies investigating faunal communities in human-modified landscapes. This project assessed the herpetofaunal community in dry dipterocarp forest, secondary disturbed forest, and Eucalyptus plantations in the Sakaerat Biosphere Reserve. In May, June, and September of 2015, we surveyed using 10 passive trapping arrays. Both the Eucalyptus plantations and secondary disturbed forest habitats (224 and 141 individuals, respectively) had higher amphibian abundance than the dry dipterocarp forest (57 individuals), but we observed significant seasonal variation in amphibian abundance. During the wetter month of September, we recorded higher numbers of amphibian individuals and species. In particular, we noted that distance to a streambed influenced amphibian abundance during the rainy season. The three most abundant species in May and June were Microhyla fissipes, Fejervarya limnocharis, and Microhyla pulchra. In September, the three most abundant species were Microhyla fissipes, Glyphoglossus molossus, and Kaloula mediolineata. Our findings suggest that seasonal resources should be considered when conducting monitoring programs and making conservation decisions for amphibians

How do King Cobras move across a major highway? Unintentional wildlife crossing structures may facilitate movement

Global road networks continue to expand, and the wildlife responses to these landscape-level changes need to be understood to advise long-term management decisions. Roads have high mortality risk to snakes because snakes typically move slowly and can be intentionally targeted by drivers. We investigated how radio-tracked King Cobras (Ophiophagus hannah) traverse a major highway in northeast Thailand, and if reproductive cycles were associated with road hazards. We surveyed a 15.3 km stretch of Highway 304 to determine if there were any locations where snakes could safely move across the road (e.g., culverts and bridges). We used recurse analyses to detect possible road-crossing events, and used dynamic Brownian Bridge Movement Models (dBBMMs) to show movement pathways association with possible unintentional crossing structures. We further used Integrated Step Selection Functions (ISSF) to assess seasonal differences in avoidance of major roads for adult King Cobras in relation to reproductive state. We discovered 32 unintentional wildlife crossing locations capable of facilitating King Cobra movement across the highway. While our dBBMMs broadly revealed underpasses as possible crossing points, they failed to identify specific underpasses used by telemetered individuals; however, the tracking locations pre- and post-crossing and photographs provided strong evidence of underpass use. Our ISSF suggested a lower avoidance of roads during the breeding season, although the results were inconclusive. With the high volume of traffic, large size of King Cobras, and a 98.8% success rate of crossing the road in our study (nine individuals: 84 crossing attempts with one fatality), we strongly suspect that individuals are using the unintentional crossing structures to safely traverse the road. Further research is needed to determine the extent of wildlife underpass use at our study site. We propose that more consistent integration of drainage culverts and bridges could help mitigate the impacts of roads on some terrestrial wildlife. © 2022 The Authors. Ecology and Evolution published by John Wiley & Sons Ltd.Open access journalThis item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at [email protected]

Soil Respiration of Natural Forest, Forest Plantation and Agricutural Incubated Soils

รายงานการวิจัย--มหาวิทยาลัยเทคโนโลยีราชมงคลพระนคร, 2553Recently, scientists have focused attention on soil as a major source and sink for atmospheric CO2. Three replications of two-depth soils from eleven different ecosystem types from Sakaerat Environmental Research Station (SERS), Sakaerat Silvicultural Research Station (SSRS) and Suranaree University of Technology (SUT), Nakhon Ratchasima were collected during the first week of March, 2010. The soils were then incubated at 25°C for three days and measured their respiration rates. The highest soil respiration rate was found in sunflower with 0.823 μmol CO2 g-1 h-1 while the lowest was found in eucalyptus plantation in SUT with 0.005 μmol CO2 g-1 h-1. Additionally between two natural forests at SERS, the respiration rate of dry evergreen forest was higher than in dry dipterocarp forest with the value of 0.037 and 0.016 μmol CO2 g-1 h-1 respectively. Whereas the soil respiration rate at SSRS forests was highest in the eucalyptus plantation (0.048 μmol CO2 g-1 h-1) and lowest in acacia plantation (0.027 μmol CO2 g-1 h-1). The overall respiration rate was higher for soils from 0-5 cm than 5-15 cm, but not statistically significant difference. Soil water content and pH were positively significant related with soil respiration (p<0.01). Soil carbon, however, was also positively significant related with soil respiration but in lesser degree (p<0.05). Therefore soil water content and pH should be major driving forces for soil respiration.Rajamangala University of Technology Phra Nakho

Preliminary Census Study of Red-shanked Douc Langur and Other Primates in Hin Namno, Khammouane, Lao PDR

หนึ่งอาจารย์หนึ่งผลงาน ประจำปี 255

Application of New MODIS-Based Aerosol Index for Air Pollution Severity Assessment and Mapping in Upper Northern Thailand

This paper reports capability of a newly-proposed index called the aerosol prediction index (API) in the determination and mapping of near-ground PM10 concentrations (at spatial resolution of 500 x 500 m) during the 2009 and 2010 burning seasons in upper northern Thailand. API is a normalized index defined based on the difference in the observed reflectance data at two spectral bands of the MODIS instrument aboard NASA�s Terra satellite; Band 3 (blue) and Band 7 (mid-infrared). Initial analysis suggested that API had strong correlation with the corresponding MODIS-AOD and AERONET-AOD with coefficient of determination (R2) about 0.62 in both cases, and also with the reference PM10 data with R2 of 0.66. In terms of predictive performance, it exhibited low bias at low PM10 condition and achieved impressive prediction accuracy with relative error of 10.78 %. The near-ground PM10 concentration map yielded from the proposed index was proved very useful in the comprehensive assessment of aerosol pollution situation over entire area at fine spatial detail. This task could not be fulfilled from sole use of the ground-based measured data or standard MODIS-AOD product. These findings indicate that API should be a promising tool for the regular monitoring of air pollution severity over the concerned area