A study was carried out at the treeline ecotone (3,730m-3,950m asl) of Langtang National Park in central Nepal with an aim to document the impact of climatic warming on ecological chracteristics. Three sampling sites were selected at Chaurikharka and Lauribina, where no serious anthropogenic pressure was noticed. The nearest meteorological station has records of climatic warming in recent years. Six tree species and three shrub species belonging to seven families were enumerated from the study plots. The average basal area for tree species was found to be 20.56 m2 per ha while average tree density was found to be 734 trees per ha with Abies spectabilis as dominant species. The mean DBH (diameter at breast height) of tree species was found to be 15.8 cm (max. 115.5cm). Density of dead trees accounted 2 no. per ha with basal area 0.195m2 per ha. Average sapling and seedling density of tree species per ha was observed to be 1,590 and 831 respectively. The average sapling and seedling density of A. spectabilis was 255 and 350 per ha respectively. Similarly, average shrub density (per ha) for the area was found to be 9,609 no/ha. The stand character showed that there was high level of recruitment of A. spectabilis in the recent years. The presence of sapling and seedling of A. spectabilis at higher altitude showing linear relationship with canopy coverage indicated prospects for a gradual and upward shift of A. spectabilis with increased temperature. Key words: Abies spectabilis; regeneration; climate change; DBH DOI: 10.3126/njst.v11i0.4132Nepal Journal of Science and Technology 11 (2010) 107-114

Viable seeds of paddy and barnyard grass in different concentrations of aqueous extracts ( 2, 4, 6, 8 and 10 %) of leaf, stem and root of Chromolaena odorata were germinated at room temperatures. The leaf extract had strong inhibitory effect on seed germination as well as linear growth of paddy and barnyard grass. The order of inhibition was leaf >stem >root on both tested seeds. Allelopathic effect increased with increased concentration of the extracts. Key Words: Allelopathy; Paddy; Barnyard grass; Aqueous extract; Root length; Shoot length. DOI: 10.3126/sw.v8i8.3854 Scientific World Vol.8(8) 2010 pp.73-75

A study on the regeneration of the Shorea robusta Gaertn in tropical forest of Palpa district was carried out during June-November, 2005. The altitude of study area ranged from 200 m -700 m asl in north facing slope. The study area was natural forest where, Shorea robusta and Terminalia alata, were dominant species .The size class distribution of Shorea robusta resembled the reverse J-shaped curve indicates better regeneration of sal in study area. Sapling and seedling density of Shorea robusta significantly correlated (p=0.01) but was no significant relation with soil parameter. Keywords: Regeneration; Shorea robusta; Size Class distribution Tropical Forest DOI: http://dx.doi.org/10.3126/sw.v9i9.5519 SW 2011; 9(9): 53-56   DOI: http://dx.doi.org/10.3126/sw.v9i9.5518