Altitude And Slope Affect On Biomass Of Rhodiola Fastigiata

Rhodiola fastigiata which is a perennial herbaceous plant of Crassulaceae is one of the important traditional Chinese herbal medicines. As its medicine use for Tonic Action, anti-senescence and so on, it have been picked up a lot, so it is in near danger state now and listed in The red list of china species(VOL.1). 19 altitude levels including the same altitude level in different slopes were set from 4070m to 4640m, the level transect with 100m×0.5m was surveyed each altitude. The crown length, crown breadth, stem diameter and stem length were measured. Individual number, stem length, soil status main species were all studied to explore altitude and slope which had influence on biomass and population density of Rhodiola fastigiata. The main results were shown below:1 Ontogeny law of Rhodiola fastigiataAs the altitude increases, the changing of stem dry weight, scape dry weight, leaves dry weight and aboveground dry weight appearsed to be wavy in sunny slope. The changing of stem dry weight and aboveground dry weight appearsed to be first decreased and then increased further reduce while the changing of scape dry weight and leaves dry weight appearsed to be first increased and then decreased in shady slope. As the altitude increases, the variation coefficient of stem dry weight, scape dry weight, leaves dry weight and aboveground dry weight had no obvious rule in sunny slope. As the altitude increases, the variation coefficient of stem dry weight appearsed to be first increased and then decreased further increased. The variation coefficient of scape dry weight was reduced, the aboveground dry weight and leaf dry weight coefficient of variation showed a V shape. Root-shoot ratio(R/T) of Rodiola fastigiata showed a tendency of decrease with increase of age.2 Changes in population density of Rodiola fastigiataPopulation density of Rodiola fastigiata was significantly greater in sunny slope than in shady slope (P <0.05). It was 0.193 individual/m2 in sunny slope, 0.101 individual/m2 in shady slope. Population density at 4640m which was 2.060 individual/m2 was the highest, while population density was less at other altitudes in sunny slope. Population density at 4470m was the highest and 1.440 individual/m2 while at 4570m was the smallest and 0.200 individual/m2 in shady slope. Population density was not significantly correlated with moss cover in sunny slope while population density was significantly negatively correlated with moss cover in shady slope. The correlation coefficient was -0.938 (p <0.05).3 Changes biomass of Rhodiola fastigiata(1)Changes biomass of Rhodiola fastigiata at different altitudesIt was at 4640m altitude where modular biomass and aboveground biomass of Rhodiola fastigiata was highest. The distribution ratio of biomass in stem, scape, leaves and fruit was stem> leaves> scape> fruit. Both stem and leaves had a large proportion.The distribution ratio of biomass in stem and scape was more than 80%.As the altitude increases, the changing of stem biomass, scape biomass leaves biomass and aboveground biomass appearsed to be the same rule. As the altitude increases, the changing of stem biomass showed an M shape at 4070—4470m while showed a J shape at 4520—4640m in sunny slope. The changing of biomass appearsed to be first increased and then decreased in shady slope. Biomass of Rhodiola fastigiata was no significant difference at 4420—4570m (P> 0.05) between in shady slope and in sunny slope.As the altitude increases, the changing of fruit biomass showed a N shape at 4070—4370m while Rhodiola fastigiata had no fruit at 4420m and the changing of fruit biomass showed a J shape at 4470—4640m in sunny slope. The changing of fruit biomass appearsed to be first decreased and then increased further reduced in shady slope. Fruit biomass of Rhodiola fastigiata was significant difference between in shady slope and in sunny slope at the same altitude (P<0.05). In sunny slope, Rhodiola fastigiata fruit biomass which was significantly positively correlated with population density and aboveground biomass was significantly negatively correlated shrub cover and total coverage. Fruit biomass was non-significantly correlated with environmental factors in shady slope.As stem biomass increases, scape biomass and leaves biomass of Rhodiola fastigiata were increased both in sunny slope and in shady slope. Rhodiola fastigiata scape biomass and leaves biomass were significantly positively correlated with stem biomass. Higher correlation coefficient was between 0.976 and 0.997.(2) Changes of Rhodiola fastigiata at deferent residual growth yearsThere was missing order at some altitudes in sunny slope. It was lack of gradeⅠindividual at 4070m and 4520m, gradeⅣindividual at 4620m and gradeⅥindividual at 4270m. There was not missing order in shady slope. It was greatest residual growth years which was different at different altitudes. As residual growth years increases, aboveground biomass and stem biomass had the same rule while scape biomass and leaves biomass had the same rule.(3)Changes biomass of Rhodiola fastigiata at different slopesRhodiola fastigiata biomass of stem, scape, leaves and aboveground were greater in sunny slope than in shady slope. Modular biomass of Rhodiola fastigiata was significantly different between in shady slope and in sunny slope (P<0.001).