| The alpine shrub communities distributed in Jinqianghe of the eastern Qilian Mountains are two subtypes: evergreen corious leaf shrub community including Rhododendron capitation + R. thymifolhm and R. przewalsldi, and alpine deciduous shrub community including Salix cupularis, Dasiphora fruticosa, Berberis diaphana, Caragana brevtfolia, Sibiraea angitstata and Hippophae tibetica. The aspect and degree of slope are main factors affecting me distribution of above-mentioned shrub communities.The shrubs of Rhododendron community are low-growing and dense. The leaf of Rhododendrons is featured with tinsel, cereous, corious and evolute aspects. Most of species are hemicryptophytes, phanerophytes and geophytes, meanwhile, the therophytes and chamaephytes account ftr only 10.5%.The aboveground phytomass of the community shows a single peak curve, and it reaches the peak value (9502 g/m2 DM) in August The community phytomass is comprised mainly by Rhododendrons, it accounts for 72.5% of aboveground and 62.8% of underground phytomass. The caloric values of R. capitation and R. thymifotium are 21.94 KJ/g and 21.68 KJ/g. The caloric value order of./?, capitation and R. thymifolhm for different part is leaf > stem > root The aboveground net primary productivity of Rhododendron is 301.7 g/m2 DM, and its total solar conversion efficiency is 0.1021%. The community keeps a low increasing pattern during growth period; this is one of features of climax.The life history of Rhododendrons includes 4 stage: germination stage, pie-over-winter stage and winter quiescent stage/The order of blooming date of Rhododendrons is R. przewalsldi, R. OiyintfoKiim,R.capiiarumm&R.anthopogonoidesLanzhou, the Rhododendrons appear inadaptation. But X. przewalstu has the potential adaptation among them.The water content in leaf and stem of Rhododendrons is higher in June, July and August and the maximum is in July. The growth increment of stem accounts for 60% ~ 80%. The net photosynthetic rate varies among Rhododendrons and R. przewalskii lasts longer photosyntheticIaccumulation. Light repression is the adaptation of Rhododendron community with high canopy density to environment, it reflects the dependence of plants in alpine area on temperature during photosynthate accumulation.Rhododendron community has the significant segregative feature within the range of altitude from 2950 m to 3700 m. R. thymifoliwn and R. capitation are dominant in the area under 3300 m. R. anthopogonoides and R. przewalskii appear from 3100 m. Their coverage is increasing rapidly from 3300 m and become constructive and dominant species. The constructive species are replaced by R. przewalskii from 3600 m. All shrubs except R. przewalskii show random distribution in the lower area, however, along with the altitude, the distribution pattern of R. przewalskii changes from random distribution to aggregated distribution because of its higher adaptability to harsh climate.The weak electric signal from stem and leaf of Rhododendrons is composed with periodic group waves. With the increase of water culture time, the wave period occurs prolongation. The minimal sawtooth waves turn up within amplitudes of two single waves when sever water loss symptom of leaf represents. In CV graphs and DPV graphs, the summit current of oxidoreduction electric potential is decreased significantly and the oxidoreduction electric potential difference is increased relatively. This means the DNA of 4 Rhododendrons interact with CoCen^3*. The adaptive strategy were analyzed in quantity by the CV graphs, DPV graphs and the value of A Ep /A260 on the interaction between the DNA and Co(en)33+. The results from electrochemistry analysis are same as the result of morphology and physiology, i.e. R. przewalskii > R, anthopogonoides > /?. capitation.The content of organic matter (OM) in the soil of Rhododendron community shows a saw-like fluctuation. The available nitrogen (AN) is positively correlated with OM ( r = 0.8794, /*<0.01). The contents of total nitrogen (TN) and total phosph...
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