Climatic Effects on Foliar Elemental Compositions of Si, Al and Fe from C4 Grass Family, China

The climate controls vegetation distribution and the vegetation reflects regional climates. Understanding the effects of climate on the elemental composition of plants is important to reveal vegetation's elemental compositions -climate relationships, and to offer references for global climate change research. China's data sets including 201 observations of leaf silicon (Si), aluminum (Al), iron (Fe) for Foxtail grass (Setaria viridis), Feather grass (Chloris virgata), Goose grass (Eleusine indica) at 55 sites and their associated climate indices demonstrate an important acclimation response of the plants to climatic factors (variability in precipitation, temperature and latitude etc..). Our studies showed that, leaf Si and Al contents and the Si/Al ratio were correlated with latitude, mean annual temperature (MAT) and annual rainfall (MAP), and leaf Fe was correlated with MAP in Foxtail grass across China; Leaf Si and Fe were correlated with latitude, and leaf Al was correlated with MAT, and leaf Al and Fe were correlated with MAP in Feather grass; Leaf Fe was correlated with latitude, leaf Al and Fe were correlated with MAT, and leaf Si, Al and Fe were correlated with MAP in Goose grass. All of this indicates that geographic gradients of precipitation and temperature constrain contents and ratios of Si, Al and Fe in plants. These findings can help initiate a more holistic approach and offer references for the eventual development of alternative indices of precipitation and temperature factors in climate change research.