根系生态学过程是植物生态学研究的热点和难点。细根作为根系中快速周转的功能单元，在全球生态系统碳氮循环中占有极其重要的地位。但目前对于细根生长、死亡的了解十分有限，尤其缺乏细根寿命对气候变化响应的研究。本项目拟通过增加夏季降水和氮沉降的控制试验，依托新疆策勒站的长期根系生态学试验场，采用自行研制的大型根窗法，研究干旱区三种功能群12种多年生植物的出生时间、死亡时间；明确细根寿命在物种和功能群尺度上的变异格局；阐明增加夏季降水和氮沉降对细根的出生季节、出生高峰、死亡季节、死亡高峰、分布深度的交互作用；进而揭示细根寿命与功能群、物种、降水、氮沉降、分布深度、出生季节之间的相关关系，确定影响细根寿命的主要因子；建立细根寿命与增加夏季降水和氮沉降的关联模型，预测并量化增加夏季降水和氮沉降对细根寿命的影响，完善AEM模型缺乏的寿命数据，为干旱区气候变化背景下的根系生态学过程研究提供定量化分析工具。

The study of root system process is currently a hot topic and a difficult point in plant ecology. As an important function unit in root system, fine root plays quite an important role in the cycling of carbon and nutrient in global ecosystem. But the knowlege on the basic function of root system and other aspects, such as growth, death and metabolic is very limited, especially in the context of global climate change. The project choose the comprehensive testing ground in Cele National Field Research Station in Xinjiang as research base, under the conditions of increased summer precipitation and nitrogen deposition, 12 kinds of perennials as research object. We use large rhizotrons to verify the basic pattern of fine root life span of plant 12 species, including 4 arbors, 4 shrubs, and 4 herbs, through the comparsion of life span at different soil depth in the variation of different species to define the basic pattern of fine root life span in the 12 species. By exploring the pattern of variation of the main functional characteristics of roots in arbors, shrubs, and herbs, the conservation and variation pattern of plant on different stages of evaluation, and finally to quantify the impact of inreased summer precipitation and nitrogen deposition on the fine root life span and to complement AEM model and provide quantitative analysis tools for the study of arid zone under climate change background.