Song Cheng-Jun, Ma Ke-Ming, Fu Bo-Jie, Qu Lai-Ye, Liu Yang, Zhong Jian-Fei
State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, China.
Ying Yong Sheng Tai Xue Bao. 2009 Aug;20(8):1797-804.
To study the influence of resources thresholds on plant growth is a major theme in restoration ecology. Based on the simulation of the natural thresholds of soil moisture, nitrogen (N), and phosphorus (P) under drought condition in the arid valley of Mingjiang River, a full factorial experiment was designed to study the dynamics of Bauhinia faberi seedlings survival rate, growth, biomass production, and resources use efficiency across one growth season. High soil moisture (40% field water capacity), high soil P (24 mg P x kg(-1)), and low N (100 mg N x kg(-1)) increased the seedlings survival rate, and promoted the seedlings growth, biomass production, and water use efficiency. There was a significant coupling effect between soil N and P, but the interactions between soil moisture and soil N and P were not obvious. High N (240 mg N x kg(-1)) restrained the seedlings growth markedly, while high P mitigated the negative effects of high N via increasing root area, root length, and root mass to promote the seedlings N and P uptake. The N and P use efficiency across one growth season kept steady, and had significant positive correlation with root/shoot mass ratio. The combination of high soil moisture, low N, and high P promoted the seedlings growth effectively, while that of low soil moisture, low P, and high N inhibited the seedlings growth markedly.
研究资源阈值对植物生长的影响是恢复生态学的一个主要主题。基于对岷江干旱河谷干旱条件下土壤水分、氮（N）和磷（P）自然阈值的模拟，设计了一个全因子试验，以研究一个生长季节内峨眉紫茎泽兰幼苗存活率、生长、生物量生产和资源利用效率的动态变化。高土壤水分（田间持水量的40%）、高土壤P（24 mg P x kg(-1)）和低N（100 mg N x kg(-1)）提高了幼苗存活率，促进了幼苗生长、生物量生产和水分利用效率。土壤N和P之间存在显著的耦合效应，但土壤水分与土壤N和P之间的相互作用不明显。高N（240 mg N x kg(-1)）显著抑制幼苗生长，而高P通过增加根面积、根长和根质量来促进幼苗对N和P的吸收，从而减轻高N的负面影响。一个生长季节内N和P的利用效率保持稳定，且与根冠质量比呈显著正相关。高土壤水分、低N和高P的组合有效地促进了幼苗生长，而低土壤水分、低P和高N的组合则显著抑制了幼苗生长。
