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Fluorinated nitriles have been proposed as low-global-warming-potential substitutes for industrial applications such as plasma etching and as dielectric materials in high-voltage equipment. FT-IR spectroscopy was used to measure the radiative efficiency of CH2FCN and its reactivity towards Cl and OH radicals, and to determine products from the Cl reaction. Relative rate experiments yielded rate constants for Cl and OH reactions of (2.1 ± 0.3) × 10−14 and (7.0 ± 1.0) × 10−14 cm3 molecule−1 s−1, respectively. The estimated atmospheric lifetime of CH2FCN with respect to radical attack was estimated to be 0.45 years, which, combined with the radiative efficiency of 0.042 W m−2 ppb−1, implies a 100-year global warming potential of 20. FCOCN was observed as the only organic product of the Cl-atom reaction in air, consistent with a dominant role for H-abstraction. Absolute infrared cross-sections for FCOCN were determined, to assist future experiments where this molecule may be formed. Quantum calculations at the CBS-APNO//B2PLYP-D3/cc-pVTZ level indicate similar energy barriers to addition and abstraction for OH radical attack, but the looser transition state and greater opportunity for tunneling also favor abstraction in this case. [ABSTRACT FROM AUTHOR]

Honey is prepared by bees from nectar or honeydew and has great nutritional and therapeutic benefits. However, air pollution affects honey quality as bees collect nectar, pollen, water and propolis from polluted and unpolluted areas. For this study, air pollution measurement and bee hive experiment were carried out concomitantly in Olakha (urban) and Ngabiphu (rural) in the Thimphu District in 2022. It was found that the annual mean PM2.5 was 19.43 µg/m3 and 8.87 µg/m3 while PM1 recorded were 16.63 µg/m3 and 4.05 µg/m3 in Olakha and Ngabiphu respectively. The honey produced by using Apis mellifera hive experiment from Ngabiphu and Olakha was collected, and the honey produced from Apis cerana sold by farmers at the Thimphu Centenary Farmers Market was purchased to compare pH, ash content, and heavy metals mainly Pb, Cd, Ni, and Cu. Twenty four samples from three places (8 each) were kept at room temperature and in the dark until laboratory analysis was carried out in Nepal Environmental and Scientific Services in Kathmandu. The data were analyzed using One-way Anova. It was found that the ash content and pH of the honey were within the international permissible limit. The Pb and Ni were not detected but the Cd content was detected only in six honey samples. There was a statistically significant difference of Cu content (p= 0.003816, a=0.05) in honeys and the mean readings were 2.86 ±0.84 µg/g, 2.55±0.91 µg/g, and 4.24±1.05 µg/g in Olakha, Ngabiphu and Market honey respectively. [ABSTRACT FROM AUTHOR]

Human wildlife conflict (HWC) represents a growing concern for the agro-pastoral community living near protected areas. We investigated the effects of crop damage by wild animals on the food security of local households and explored potential solutions. Data were collected through semi-structured interviews conducted with 250 households and 21 key informant interviews around the Koshi Tappu Wildlife Reserve, Nepal. Our results revealed that 96% of the respondents had experienced conflicts with wild animals, of which 66% reported rice as a major damaged crop. Annually, 320 kg of rice per household was damaged, which is equivalent to one-third of the annual consumption for each household in the study area. Wild elephants were the key contributors (62%) to this damage. To mitigate HWC, 59% respondents suggested construction of concrete walls around the affected areas. In addition, mobilization of the local community in conservation stewardship helps reduce HWC. [ABSTRACT FROM AUTHOR]

In many developing countries, the only affordable approach to recover ecosystem structure and function is through passive restoration. We conducted a 3 year study of passive restoration in mixed Dipterocarp forests dominated by Shorea robusta to examine the effectiveness of exclusion (fencing and fire suppression) on diversity, density, and richness of regenerating tree seedlings and saplings. We analyzed excluded and disturbed paired sites. We observed exclusion was effective in increasing seedling richness and occurrence of S. robusta and Syzygium cumini. A significant improvement in sapling strata (diversity, density, and richness) from excluding the disturbances was observed. Mean sapling density estimated was about 500% higher in excluded compared to disturbed sites. Probability of occurrence of S. robusta and Dalbergia latifolia saplings increased due to exclusion. That said, presence of exotic species Chromolaena odorata was higher in excluded sites reflecting the need for assisted natural regeneration in forests. This study has demonstrated passive restoration as an effective approach for improving natural regeneration in mixed Dipterocarp forest ecosystems and possibly other similar forest types, and will serve as a reference document for future restoration interventions. [ABSTRACT FROM AUTHOR]

The Smooth-coated Otter (Lutrogale perspicillata) (SCO) is a semi-aquatic, top predator and a biological indicator of freshwater environments. We assessed the distribution of SCO and its relation to habitat variables in the Kauriala branch of the Karnali River. We searched for evidence of SCO in plots of 100m x 10m in the middle of each of 70 transects of 1 km, on both sides of the river, on a 39km stretch of river. Signs of ocupancy were observed in stretches where the river width ranged from 50 m to 300 m, but river width was negatively associated with probability of occurrence of SCO. Observed signs of SCO were maximal in areas of shrub cover and sandy substrate. Human activity is considered to be the most pressing threat, followed by grazing, stone extraction, fishing and construction activities. Formulation and implementation of a SCO conservation action plan should be prepared to protect the species in the Karnali River. [ABSTRACT FROM AUTHOR]