| Seriphidium transiliense belongs to Compositae Seriphidium plant that it concentrated distributed in the flatland and low mountain region of north, which is the main forage of spring-autumn pasture in Xinjiang. Because the ecological environment is fragile, nature condition is poor, in addition, the management is shortage, overgrazing, people's factors and so on. All the reasons caused the type grassland serious degradation, at the same time, it also leaded regional ecological environment deterioration, the coverage of vegetation decreased, the area of bare land was increased, grass- soil-livestock imbalanced, which seriously restricted the stable development of livestock husbandry. The experiment based on the manual setting of different mowing intensities in a small sacle range, the method of sampling was taken multiple times in a year, and we studyed the dynamic change and their formation law for physiological resistance, variation of modules composition, leaf founction characters resistance of S. transiliense. Simultaneously, we experimentially chosed the representatively typical plots in large scale range, explored the influence for modules and molecular level of S. transiliense in different habitats and different terrains under nature condition. Sampling only once in autumn,we researched the response for habitats and terrains in modules, soil and genetic diversity. In order to comprehensively revealed the ecological plasticity and disvergence adaptation mechanism, and provided scientific basis for grassland practical productical use. The main results were as follows:(1)The ecological adaptation regularity of mowing intensity for S. transiliense's physiological resistance Chlorophyll and storage nutrition substances, leaf exhibited a law as increased→decreased→increased; Stem and root had a same change law, they all presented increased→decreased→increased→decreased; Starch's root was contrary. Osmosis regulating substances had a identical law in leaf, stem and root, they all presented increased→decreased→increased→decreased; With the change of mowing intensity, C2 possesed the absolute advantage, C0 was at disadvantage. The content of nutrition substance was lower in 2008 than 2009, the main reason was the precipitation less in 2008 than in 2009, the plant had a stronger ecological adaptation.(2)The ecological adaptation regularity of mowing intensity for S. transiliense's modules With the mowing intensity increased, C2 could promote modules of plant individual in a advantage position with mowing intensity increased, it showed that proper mowing could stimulate plant toward benign direction growth; Plant individual of C0 tended to dwarf, miniaturization and creeping finally, usually, C0 could lowered plant height, reduced branch numbers, and stopped sexual reproduction, underground, plant individual could increase root dry weight or other measures to adapt mowing stress and maintain life; Mowing time had a large influence for plant, mowing in autumn stressed for plant more serious than mowing in spring.(3)The ecological adaptation regularity of mowing intensity for S. transiliense's leaf function charactersCompared with LDMC and single leaf relative water content, SLA had more sensitive for mowing intensity than other indexes; Mowing in spring was more obvious influence than mowing in autumn, C5 appreciably possessed advantage, C0 was also ranking in the end, it had the worst ecological adaptation for mowing intensity.(4)The ecological adaptation for habitats and terrains of S. transiliense's modulesThere could be determined that growth condition of Chabuchaer country was the first in different habitats, Xinyuan country, Shawan country and Urumqi city were in the middle, and Qitai country was the last one. Plant individual difference was the smallest and uniformity was the best of Qitai country in the five habitats. The contribution rate of stem dry weight for aboveground biomass and main root dry weight for underground biomass all were the largest, and there even was a strong positive correlation and had a similar fitting function between them, and also had same material production and accumulation trend. In different terrains, the S. transiliense in flatland and sunny slope had a stronger ecology adaptation than in shady slope or hilly. The contribution rate and fitting function of aboveground and underground biomass in different habitats and different terrains got a similar conclusion.(5)The ecological adaptation for habitats and terrains of S. transiliense's soil chemical propertiesHabitats and terrains had a influence for soil chemical properties and there was existing interaction or hindrance effect in every index, but organtic matter,available nitrogen,available kalium and available phosphorus had a consistent change trend on soil profile structure, which were 0-10cm>10-20cm>20-30cm, soil pH was 0-10cm<10-20cm<20-30cm, and soil total salt was 10-20cm>20-30cm>0-10cm. Soil total salt and pH had a negative correlation with other soil nutrients. The main form in soil organtic matter, available nitrogen, available kalium and available phosphorus all were flatland>sunny slope>shady slope>hilly. There was no explicited law in terrains for soil pH, soil total salt presented a strong law that was shady slope>sunny slope>flatland.(6)The ecological adaptation for habitats and terrains of S. transiliense's genetic diversityPercentage of polymorphism loci of S. transiliense was 78.4%, polymorphism band numbers were probably at the same level in different population amplification on the same primer combination. In one population, it presented that plant individual could divide two types according to water and heat, which the first type was flatland and sunny slope, the other type was shady slope; In five populations, it could be divided two types, the first one contained Chabuchaer country and Qitai country, the other one contained Urumqi city, Shawan country and Xinyuan country, and terrains effect was large than habitabs for genetic diversity of S. transiliense.
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