PDF(Pubmed)
Abstract：
Plant pH is an emerging functional trait that plays important roles in physiological processes and nutrient cycling. However, how root pH varies among plant functional groups (PFGs) and the regulatory factors on a large scale remain unclear. Therefore, we quantified root pH variation of herbaceous plants in four PFGs from 20 sites on the Tibetan Plateau along a 1600 km transect and explored the correlations between root pH and different PFGs, climate and soil conditions. The results showed that the root pH of herbaceous plants was slightly acidic (6.46 ± 0.05). Grasses had the highest root pH (6.91 ± 0.10) across all functional groups (p < .05), whereas legumes had the lowest (5.90 ± 0.08; p < .05). The root pH decreased with mean annual precipitation, aridity index, soil water content and soil stress coefficient, whereas the significant positive correlation with soil pH. PFGs, climate and soil explained 5.39, 11.15 and 24.94% of the root pH variance, respectively. This study provided a comprehensive analysis of root pH patterns in herbaceous plants over a large spatial scale. Root pH was controlled by the combined influence of PFGs, climate and soil properties, with moisture status being the main influential factor. In contrast to the leaf pH, the root pH of herbaceous plants is strongly affected by the soil pH along environmental gradients. Our findings provide new insights into root functional traits and survival strategies of herbaceous plants in alpine ecosystems.
摘要：
植物pH是一种新兴的功能性状，在生理过程和养分循环中起着重要作用。然而,植物官能团（PFG）和调节因子之间的根pH如何变化尚不清楚。因此,我们量化了来自青藏高原20个地点的四个PFGs中草本植物的根系pH变化，沿着1600km的样带，并探讨了根系pH值与不同PFGs之间的相关性。气候和土壤条件。结果表明,草本植物根系pH呈微酸性(6.46±0.05)。在所有功能组中，草的根pH值最高（6.91±0.10）（p<0.05），而豆类最低（5.90±0.08；p<.05）。根系pH值随年平均降水量而下降，干旱指数，土壤含水量和土壤应力系数，而与土壤pH呈显著正相关。PFGs,气候和土壤解释了根系pH变异的5.39、11.15和24.94%，分别。这项研究提供了在大空间尺度上对草本植物根系pH模式的全面分析。根pH值由PFGs的联合影响控制，气候和土壤特性，水分状况是主要影响因素。与叶片的pH值相反,草本植物的根系pH值受环境梯度土壤pH值的强烈影响。我们的发现为高山生态系统中草本植物的根系功能特征和生存策略提供了新的见解。
