| The taxonomic status of Longwhip Rhodiola (Rhodiola fastigiata) is at Ser. Fastigiatae, Sect. Chamaerhodiola, Rhodiola, Crassulaceae. There are 9 species in the Ser. Fastigiatae, and 8 species are distributed in China. They have unique life form/chamaephyte & nanophanerophyte. The life form of others from Rhodiola is hemicryptophyte & geophyte. It is very special that Longwhip Rhodiola's life form is nanophanerophyte as herbaceous psychrophyte. The plant live age can be identified by scape ring's quantity in caudex.Longwhip Rhodiola's quantitative characters have been researched at 7 types of community, they are fir forest(P1), juniper open forest(P2), rhododendron shrubs(P3), procumbent willow brushwood(P4), rhododendron dumi(P5), willow shrubs(P6) and subshrub thicket(P7) in altitude 4150～4680 m. The average density range is P3>P1>P2>P4>P6>P7>P5. The average basal diameter range is P6>P2>P7>P5>P4>P1>P3. The average height range is P6>P2>P7>P5>P1>P3>P4. The scape quantity range is P6>P7>P2>P1>P3>P5>P4. The scape ring quantity range is P7>P6>P5>P2>P1>P3>P4. The branch quantity range is P6>P1>P3>P2>P4>P7>P5. The importance value range is P5>P7>P4>P3>P2>P1>P6. The young is lesser, adult and agedness is major on the whole. The population reproduces in large quantities with periods about 11～15 years. Various growth parameters are positive correlation with basal diameter grade.The biomass in juvenile phase accumulates at underground part mainly. After they became to maturity, the biomass root-canopy ratio changed shrunken with that annual increment of caudex length is round about 1.5cm, annual increment of biomass is about 0.5g, while the fleshy roots perished gradually and regenerative adventitious roots possessed minuscule biomass. Production and reserve of nutrient, still including breeding activity depend on the growth of caudex. Individual biomass of overground part has not any pertinence to altitude, but sunny place is greater than shady place.Spatial distribution pattern of Longwhip Rhodiola population shows conjoint state between aggregated distribution and random distribution in the mass, but it approached to aggregated distribution.The niche breadth of Longwhip Rhodiola is most, and of the other dominant species has small difference. In the community, each dominant species distribute evenly and widely. Among the populations, competition is invisible and sharing is obvious to resources. The niches overlap highly between Longwhip Rhodiola and the most of other populations, but there is not intense competition among them.The population density has not any pertinence to altitude. The average density is 1.37 one·m-2 by typical population in investigation zone.The population biomass of overground part is the most/96.60 g·m-2 at 4640m. Its changes have not any pertinence to altitude, but the discrepancy is very large that the most multiple is 369 times (sunny 4640m/shady 4570m), and is 138 times at same slope aspect(sunny 4640m/sunny 4520m). The average population biomass of overground part is 1.90g·m-2 (without 4640m'96.60 g·m-2) as impersonal data with resources appraisal. Biomass proportion of each apparatus shows caudex>leaf>scape>fruit. The caudex predominates absolutely with 73.2% at sunny place,59.3% at shady place, and their changes have not any pertinence to altitude. The population biomass of fruit at sunny place shows the most distinct positive correlation to population density and biomass of overground part, and shows distinct negative correlation to coverage of shrubs and trees. The population biomass of fruit at shady place has invisible pertinence to E-factor. The population at shady place is more senescent than at sunny place.Genetic variation' 27.79% is among the associations, and 72.21% is in the associations.The seeds of Longwhip Rhodiola pertain to enforced dormancy type. It has been unsuccessful that was by artificial seeding in situ. Germinant process is not conditioned by mutative and constant temperature. Its most suitable temperature is at 20～25℃, incompatible to arctic-alpine habitat. Author deduced that Longwhip Rhodiola was traceable in the lower altitudes, and is in a selected or adaptive phase at present. Its simplex fecundity is higher distinctly than Salix pilosomicrophylla, which is a kind of dioecism/chamaephyte/psychrophyte at same habitat with Longwhip Rhodiola, but dormant ability of seeds is lower greatly than Salix pilosomicrophylla.Seeds germination and seedling growth of Longwhip Rhodiola are restricted by other species. The inhibiting effect attained very conspicuous level through the growing process of seedlings, from which the inhibitor was respective water extracts of fir, willow and moss, and. it attained conspicuous level from water extracts of Rhododendron. It is not conspicuous that Longwhip Rhodiola affects itself seedlings.According to the regular mensuration at MDA, SOD, POD, CAT, AsA, chlorophyll, carotenoid, osmoregulatory matter, UV-B protection parasites, the results show that low temperature and UV-B is arctic-alpine stress factor to Longwhip Rhodiola, low temperature is an important stress factor, the compound with UV-B and low temperature has conspicuous threatening effect. However, there is a complementary mechanism among the various compositions in Longwhip Rhodiola's stress-response system, and its population has been provided with a strong resistibility.The effect of rhizosphere microbe is highly significant, and there are a mass of PGPR and mycorrhizal fungi.Longwhip Rhodiola possesses hermaphrodite flowers and female flowers only, do not male flower. The ripening rate of hermaphrodite flower is very low (only 2.85%), and they only officiate the function of male flowers. The main limiting factor of its reproductive success is resource limited that is reflected at the site condition. It has large reproductive potential but small fecundity, and the loss rate of buds is 61.5%, of inflorescent flowers is 50.2%, of ovules is 89.6% during the process from buds to seeds, these changes have not obvious pertinence to altitude.The florescence of its population is about 30 days with starting in late June and ending in late July. The illumination affects abloom process. Hermaphroditic's florescence (9.29 days) is greater than gynoecious's (7.06 days), and hermaphroditic blossom out earlier than gynoecious. The peak period of gynoecious's blossom out was earlier than of hermaphroditic, that this is propitious to reduce the pollen limiting. The florescence of a single has distinct positive correlation with flowers quantity, distinct negative correlation with early blooming. The early blooming of gynoecious has distinct pertinence with flower quantity, florescence and fruit yield. The index of abloom synchrony has distinct pertinence with fruit yield, but has not any pertinence with early blooming. The florescence of a single and the early blooming is main factor for fruit and seed yield. It is 14.6 that are the average quantity of seeds in a fruit, the estimated value of seed average yield in a plant is 228.6.Longwhip Rhodiola is representative heliophyte (in favor of high heliophyte), the best normal region lie in 4470～4520m, and its growing speed was decreased by altitude increasing.11～20 years age group is main body of the population at prevalent state that they seize hold of 56% and almost of them come from vegetative propagation. The plants which they own the character of seed propagation only present to 1～3 years age group and a small of 4～10 years age group. By the renewal investigation, seedling of 1～3 yeas age group has 80.6%, but of 4～10 years age group only has 0.9% that its seed propagation appears a serious breakdown. Around about 60% plants have completed vegetative propagation successfully, and vegetative propagation is a main approach for Longwhip Rhodiola population's renewal.Longwhip Rhodiola owns definite ability to withstand arctic-alpine, but is imperiled by people's collecting action. Its life history strategy is that the basis is vegetative propagation for keeping stable quantity of the population farthest, and the chance is seed propagation at infinitesimal quantity for keeping stable climbing quality of the population frailly. It is a vulnerable species. The total resources of caudex are 146.41×104t in Southeastern Tibet.The protection measure is that collecting quantity must be controlled severely, the outlay of bioreactor developing is increased for depressing cost of production, and he outlay of domesticating is increased for that they can grow properly at the low altitude and the commercial caudex contains active ingredient substantially, author offered.
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