Floristic composition of Bryophytes and its diversity along the elevation gradient of Palpa District, Nepal

Abstract

Bryophytes are very important groups of land plant with a varied ecological and economic importance. These are second most diverse group after angiosperm, though least concerned group in the field of research and documentation. Various studies have suggested making an initiation to promote research on various unexplored region of Nepal so as to complete the documentation process of bryoflora. The aim of this study is to record the floristic information of the bryophytes, its species richness in relation to various environmental variables including the soil macronutrient along the tropical and sub-tropical band Palpa district where no studies are taken place till date. Systematic random sampling methods was used where the circular plots of 10 m radius was laid with 5 (1 m x 1 m) subplots each. Similar 5 sample plots were laid 50 m in each elevation band. The elevation band of the study area was from 300 m- 1500 m where the plots were laid at an interval 300± 85 m depending upon the topography. In each plot various environmental variables were recorded such as elevation, canopy cover, bareground, rock cover, other plants, herb cover, bryophytes cover, organic carbon, nitrogen content, phosphorous, potassium. In total 39 species were collected from the study area with dominancy of mosses. The regression analysis showed statistically significant linear inclining relation with elevation gradient. Declining linear relation was found for canopy cover and total species richness and also for both liverworts and mosses but the variable was insignificant for the hornworts. Declining linear relation was also shown for bare ground and the relation with other plants species, rock cover, herb cover, herb cover and various soil parameter (Organic matter, Nitrogen, Potassium, Phosphorous) was insignificant but mosses showed significant declining relationship with Potassium content though various studies showed significant relations with the soil macro-nutrients. We expected that the study will give more species as compared to previous study done in the western region in the same elevation which was not true. So, there might be soil and rock parameters which may be the reason of low richness of the species. So, further research with soil micro- nutrients and rock parameter may suggest the clear reason of the low number of species.