Amorpha Fruiticosa Phenotypic Plasticity And Plant Resource Allocation In The Qinghai-tibet Plateau

At present, the Qinghai-Tibet Plateau desertification is expanding and spreading, it has become a long-term and arduous project to prevent desertification, especially in cold areas. Amorpha fruiticosa, the various characteristics of which to different habitat, is an excellent alpine shrub in the northwest and southwest of China. Discuss and compare morphological characteristics, nutrient concentrations of A. fruticosa in the Qinghai-Tibet Plateau (Lhasa, Maqu), there was complex correlation between morphological indexes and nutrient element concentrations of A. fruiticosa in both regions, which reveals various potential nutrition value and adaptive strategies of A. fruiticosa to alpine habitat. This study reported in the first time the variation in the main morphological characteristics of A. fruticosa plants in the alpine regions which may have important implications for the management of such alpine grasslands in China.17morphological characteristic indexes and11nutritive elements(organic carbon, nitrogen, rhizosphere and so on) of five different parts of A. fruticosa which was planted in the Qinghai-Tibet Plateau (Lhasa, Maqu) were comparatively analyzed.The results showed that:1,There were striking differences in some of the morphological characteristics within and among A. fruticosa populations when compared the average coefficients of variation in these morphological characteristics. Principal component analysis (PCA) indicated that the accumulated contribution of the first four principal components was89.550%, suggesting that the first four principal components explained most of the variation in the morphological characteristics. New branch length, old branch diameter, total length of the second-order lateral root, new branch diameter, and second-order lateral root length explained the majority of the variation in morphological characteristics of A. fruticosa populations.2,Correlation analysis also indicated that there were complicated relationships between main factors (soil organic carbon, total nitrogen and so on) in the rhizosphere and the above five morphological characteristics. New branch length, old branch diameter showed significant positive or negative correlations (P<0.05) with the contents of soil nutrients, and in particular the content of soil organic carbon, total nitrogen were significantly and negatively correlated (P<0.05) with the five morphological characteristics, but the content of nitrate were significantly and positively correlated (P<0.05) with the five morphological characteristics.3, A. fruiticosa phenotypic differences existed in both regions, especially, the morphological indexes of underground parts were significantly different. The biomass proportion and nutritive element concentrations differences existed in different bodies of A. fruiticosa and between Lhasa and Maqu., which was caused by the response of plant resource allocation to alpine habitat. There was complex correlation between morphological indexes and nutrient element concentrations of A. fruiticosa in both regions.