陆地生态系统植物的氮源及氮素吸收

氮是植物生长发育所必需的营养元素,也是其主要的限制因子之一.陆地生态系统植物所需氮的来源及植物对氮素的吸收利用均受控于其种类和生长环境.环境条件的改变,一方面可能改变植物生长区原有氮的形态、浓度、赋存方式等,从而改变氮对植物的供给状况;另一方面可能引起植物生长区土壤质量、水分利用状况、光照等的改变,从而产生耦合现象,直接影响植物的生理生态特性,使植物对氮素的吸收利用发生改变,导致植物生长区的种群类型及物种多样性发生改变,并直接影响到生态系统的功能及演替.本文主要对陆地生态系统中高等植物生长发育所需氮素的来源及植物对氮素吸收利用过程中的影响因素进行了综述和讨论,并结合国内外在该领域的研究现状对其研究前景进行了展望.

Nitrogen source and its uptake by plants in terrestrial ecosystems

Nitrogen is a necessary nutritional element, and also, a main limiting factor in plant growth. The nitrogen source and its uptake by plants in terrestrial ecosystems are controlled by their types and habitats. The change of environments can change the plant nitrogen supply through changing the nitrogen form, concentration and distribution, and may lead to the change of soil quality, water regime, and illumination condition. These changes often bring coupling phenomena, and affect plant physiological and ecological characteristics, which subsequently affect the nitrogen uptake and utilization by plants. Moreover, these changes also lead to the variations of plant populations and biological diversity, and hence, directly affect the function and evolution of ecosystem. This paper mainly summarized the nitrogen sources in higher plants growing in terrestrial ecosystems, and analyzed the affecting factors during their nitrogen uptake and utilization. The prospect in this research field was discussed.