%A Yan Pan, Jirui Gong, Taogetao Baoyin, Qinpu Luo, Zhanwei Zhai, Sha Xu, Yihui Wang, Min Liu, Lili Yang %T Effect of Seasonal Grazing on Trade-off Among Plant Functional Traits in Root, Stem and Leaf of Leymus chinensis in the Temperate Grassland of Inner Mongolia, China %0 Journal Article %D 2017 %J Chinese Bulletin of Botany %R 10.11983/CBB16109 %P 307-321 %V 52 %N 3 %U {https://www.chinbullbotany.com/CN/abstract/article_3173.shtml} %8 2017-05-01 %X

Grazing represents the main way for utilization of grassland, and different seasonal grazing affects compensatory growth and regrowth by affecting the trade-off among plant functional traits. To understand the trade-off and variation among the ‘soft’ and ‘hard’ traits under different seasonal grazing, we measured soft traits such as plant height, internode length, and tillers and hard traits such as photosynthetic capacity, antioxidant system and substance contents of osmotic adjustment in root, stem and leaf of Leymus chinensis. Compared with spring grazing, under continuous grazing, L. chinensis adopts stronger avoidance and tolerance strategies. The soft traits and some hard traits, such as photosynthetic capacity, chlorophyII fluorescence characteristics and energy partition show the same trend: net photosynthetic rate decreasing in June and increasing in August. However, the plants have higher photosynthetic product in leaf under spring grazing, which is harmful for regrowth, with vast organic matter contents eaten after grazing. However, under continuous grazing, L. chinensis allocates more to stem and root, which is conducive to uptake water from soil and regrow by using the remaining organic matter. Thus, under three-year grazing, continuous grazing is better for regrowth of L. chinensis and sustainable for grassland.