草业学报2012，Vol.21Issue(4)：307-312,6.
黄土高原典型草原草地根冠比的季节动态及其影响因素
Seasonal dynamics of root-shoot ratio and the effect of factors in grazed and ungrazed grasslands of the Loess Plateau
摘要
Abstract
The allocation between above-ground and under-ground biomass is influenced by many factors such as plant species, plant age and climate conditions. It can influence carbon input from plant to soil and the carbon cycle in terrestrial ecosystems. Because it is difficult to measure the root biomass precisely, there are still some uncertainties in the root-shoot ratio (R/S) , which is considered an important parameter in carbon cycle models of terrestrial ecosystems. The seasonal dynamics of R/S were investigated in grazed and ungrazed grasslands of the Loess Plateau in 2007, 2008, and 2009, and the relationships between R/S, precipitation, and air temperature were analyzed to provide useful information for prediction of under-ground biomass and carbon cycle mod-, els in terrestrial ecosystems. The seasonal dynamics of R/S in both grasslands showed an anti-parabolic pattern, with the minimum values occurring in September. The mean R/S values in the three years in the grazed grassland (3. 13, 3. 36 and 3. 77 respectively) were significantly higher than those in the un-grazed grassland (2. 55, 2. 56 and 3. 13 respectively) (P<0. 05); At a seasonal scale, there were significant negative correlations between R/S with precipitation and mean temperature in the last two months (P<0. 05). Multiple regression equations were built to better predict R/S.关键词
围封草地/放牧草地/根冠比/降水量/气温Key words
ungrazed grassland/grazed grassland/root-shoot ratio/precipitation/temperature分类
农业科技引用本文复制引用
李旭东,张春平,傅华..黄土高原典型草原草地根冠比的季节动态及其影响因素[J].草业学报,2012,21(4):307-312,6.基金项目
中国科学院战略性先导科技专项(XDA05050403) （XDA05050403）
科技部科技支撑计划项目(2008BAD95B03) （2008BAD95B03）
国家自然科学基金项目(31070412)和兰州大学中央高校基本科研业务费专项资金(lzujbky-2010-154)资助. （31070412）
