极小种群野生植物资源冷杉与入侵阔叶树的地下竞争关系研究

植物根系对土壤养分的竞争在自然界普遍发生，很多研究发现根系竞争深刻影响了植物群落的个体数量和物种结构。在全球气候变化驱动下，极小种群植物资源冷杉(Abies ziyuanensis)的生境逐步被阔叶树种侵占，但此过程中阔叶树与资源冷杉的根系对土壤养分的竞争机制尚未得到应有的研究。本项研究从幼苗根系的形态塑性和生理塑性入手，系统分析资源冷杉和阔叶竞争种之间的土壤养分竞争机制。具体研究内容涵盖4个方面：(1)设置养分处理探测参试植物的根系形态塑性。(2)利用氮同位素和磷同位素示踪侦测参试植物的根系生理塑性。(3)根系形态和养分吸收效率在种内竞争下的变化趋势。(4)根系形态和养分吸收效率在种间竞争下的变化趋势。项目力图阐明资源冷杉-阔叶植物竞争种间的根系觅食竞争机制，以从崭新视角深入剖析资源冷杉种群衰退的复杂原因，为资源冷杉的有效保护和种群恢复奠定重要理论基础。

Root foraging competition is commonly occurrence in nature. Many studies had revealed that root foraging competition had  a profound impact on the plants individual numbers and species compositions in communities。 Under the background of global climate change, the habitat of Abies ziyuanensis, a critical endangered fir, has been occupied by broad leaf plant species year by year. Nevertheless, the underlying mechanism of root foraging competition between Abies ziyuanensis and broad leaf plants had not been studied. Starting from the seedlings root morphological plasticity and physiological plasticity, this project aims to systematically study on the mechanism of root foraging competition between Abies ziyuanensis and broad leaf plants. The research contents include four aspects: (1) Testing of seedlings root morphological plasticity under different nutrient treatments. (2) Testing of seedling root physiological plasticity by 15N isotope tracing technique. (3) The morphological change and nutrient uptake efficiency difference of seedling root in intra-species competition. (4) The morphological change and nutrient uptake efficiency difference of seedling root in inter-species competition. This project design to reveal the root foraging competition mechanism between Abies ziyuanensis and broad leaf plants, and furthermore to thoroughly analyze the complex interactions leading to the Abies ziyuanensis population decline, and finally to lay the solid theoretical foundation for the efficiency conservation and population restoration of Abies ziyuanensis.