The response of native plants to allelopathic interference of invasive species may differ from species to species. In this study, the phytotoxic effects ofAgeratina adenophorawere tested on two native shrubs (Osbeckia stellataandElsholtzia blanda) of Nepal. Both the shrubs were grown in pots under treatments ofA. adenophorafresh leaves and root leachates, and litter. Then, the seedling length and biomass were compared among the treatments. The results show thatA. adenophoralitter has stimulatory effects but the leachates from fresh leaves and root are phytotoxic to the growth and development of native shrubs. Infrared Spectroscopy (IR) analysis confirmed the presence of O–H (Hydroxyl), N–H (Amines), C≡C (Alkynes), and C–H stretching (Aromatic) or C–O–C stretching (Ethers) in the leachates representing harmful allelochemicals. The invaded soil byA. adenophorahad low pH and a high amount of organic matter, total nitrogen, phosphorus, and potassium than the uninvaded soil. The results indicate that the nativeO. stellataandE. blandaare harmed byA. adenophorain nature by leaching of allelochemicals and probably by reducing the soil pH. Overall, this study has provided valuable insights regarding the effects ofA. adenophorainvasion on native shrubs and revealing the potential mechanism of its invasiveness.

Water quality deterioration has threatened aquatic life around the world including Nepal, which has been a serious issue for environmental sustainability and economic development. This study evaluated and interpreted hydrochemical parameters of the Beeshazar and associated lakes in Central Himalaya, Nepal. The study revealed that the water in the lake was slightly alkaline as the average pH was 7.52. The correlation and principal component analysis (PCA) identified both geogenic and anthropogenic processes as the controlling factors of hydrochemistry whereas the cluster analysis (CA) showed relatively more pollution in the associated Laxmi Lake. Also, the water quality index (WQI) classified the water as “good” for drinking purposes (i.e., WQI = 33.90), while the pollution index (PI) values were characterized as sub-cleanness and slightly polluted. In general, both the WQI and PI signify that water in the lake complex is currently safe for drinking purposes. It is further confirmed from the comparative analysis of chemical variables with other lakes in the region, WHO and national water quality guidelines for aqua culture that the most of the analyzed water parameters exhibited relatively low concentrations and were within the prescribed guidelines. However, the elevated concentrations of NO₃⁻and PO₄³⁻may pose serious problems for retaining water quality in the future. The results could be considered for future planning and management of the Ramsar Lakes of the lowland areas in the Himalaya and also as a valuable reference for the freshwater researchers at the national and international levels.

The contamination of trace elements (TEs) in freshwater sources has become an alarming issue globally. This study evaluates the contamination level of TEs, their spatial distributions, and the health risks in the Ghodaghodi Lake complex, Nepal. Altogether, ten water samples were collected, and As, Ba, Cd, Co, Cr, Cs, Cu, Li, Mn, Ni, Pb, Rb, Sc, Sr, Ti, Tl, V, Y, and Zn were determined by inductively coupled plasma mass spectrometry. The results revealed that Sr, Zn, Cu, As, Sc, and Rb were dominated TEs, contributing to the contamination. The principal component analysis and correlation matrices demonstrated both the geogenic and anthropic origin of the TEs in the lake. The water quality index (WQI=10.08) and hazard indices <1 exhibited that the TEs pose a low risk to human health and, hence the water of the lake was suitable for drinking purposes. However, exposure risk assessment results suggested that children are relatively more vulnerable compared to adults. The outcome of this study will provide new insights to local people and the concerned authorities for the sustainable management of Ramsar listed Ghodaghodi Lake complex.

Rice is the most important staple crop in Nepal, playing a critical role in both the economy and food security. This study analyzes the trends in rice cultivation, production, imports, and exports from fiscal years 2011/2012 to 2021/2022 and also presents population data from the initial and final years. Over the study period, the area of rice cultivation declined by 0.81% annually, while the production grew by 1.5% per year, and the yield improved at a rate of 1.97% per year. Trend analysis indicated no significant changes in cultivation area or production, but a significant positive trend was observed in the yield. Rice import showed a significant annual increase of 5.61% in price value and 12.80% in quantity, while exports also grew by 1.95% in quantity and 2.39% in value. However, exports remain negligible compared to imports. Nepal's rice self‐sufficiency ratio (SSR) has declined by 1.15% annually, falling from 92.72% in 2011/2012 to 82.01% in 2021/2022 while its import dependency ratio (IDR) has increased by 5.89% annually. These trends suggest that Nepal is becoming increasingly vulnerable in terms of rice food security. Population dynamics based on two census records revealed a notable 14% rise in the foreign population. This situation underscores the urgent need for policy interventions to address the decline in rice self‐sufficiency, labor shortages, and growing import dependency, ensuring sustainable rice production and food security in Nepal.