J Plant Ecol ›› 2023, Vol. 16 ›› Issue (4): rtac085.DOI: 10.1093/jpe/rtac085

• Research Articles •    

Aboveground net primary productivity was not limited by phosphorus in a temperate typical steppe in Inner Mongolia

Yumeng Guo1,2,†, Meng Zhou1,†, Jun Sheng1,2, Yujia Yuan1,2, Guangyuan Yuan1,2, Wen-Hao Zhang1,2, Wenming Bai1,*   

  1. 1State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China;
    2College of Life Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
  • Received:2022-03-11 Revised:2022-05-10 Accepted:2022-08-13 Online:2022-08-25 Published:2023-08-01
  • Contact: E-mail: bwming@ibcas.ac.cn
  • About author:†These authors contributed equally to this work.

磷不是内蒙古温带典型草原地上净初级生产力的主要限制因素

Abstract: Phosphorus (P) is an essential element for plant growth, however, whether the aboveground net primary productivity (ANPP) of typical steppe was limited by P remains obscure. To detect the effects of P addition on primary productivity and aboveground biomass of different plant functional groups both under ambient and N addition conditions, ANPP and aboveground biomass of grasses and forbs were measured from 2016 to 2020 on a 16-year N and P addition experiment platform in a temperate typical steppe in Inner Mongolia. The soil available N and P concentrations were also determined to test the relationship between ANPP and the availability of soil nutrients. We found that P addition under ambient condition had no significant effect on ANPP and the aboveground biomass of grasses and forbs. However, under N addition, P addition significantly increased ANPP and the aboveground biomass of forbs. Furthermore, soil available N and P concentrations were increased significantly by N and P addition, respectively. Moreover, there was no significant correlation between ANPP and soil available P concentration, while ANPP was positively correlated with soil available N concentration. These results suggest that P is not the key factor limiting the primary productivity of the temperate typical steppe in Inner Mongolia. However, under N addition, P addition can promote ANPP and alter the community composition. These findings provide valuable information for the management of the temperate typical steppe.

Key words: aboveground net primary productivity, community composition, phosphorus, plant functional group, temperate typical steppe

摘要:
磷是植物生长所必需的营养元素,然而,温带典型草原地上净初级生产力(ANPP)是否受到磷的限制仍存在争议。为探讨磷添加在自然条件和氮添加条件下对温带典型草原ANPP和不同功能群植物地上生物量的影响,本研究利用位于内蒙古温带典型草原的中国科学院植物研究所多伦恢复生态学试验示范研究站的16年氮磷添加实验平台,对植物群落ANPP、禾草和杂类草地上生物量以及土壤有效氮、磷含量进行了连续5年(2016-2020)的测量。研究结果表明,在自然条件下添加磷对ANPP和禾草、杂类草的地上生物量没有显著影响。而在添加氮的条件下,添加磷显著增加了ANPP和杂类草的地上生物量。线性回归分析的结果表明,ANPP与土壤速效磷浓度无显著相关,而与土壤速效氮浓度呈显著正相关。这些结果表明,磷不是内蒙古温带典型草原初级生产力的主要限制因素,但在添加氮的条件下添加磷可以提高温带典型草原的ANPP并改变植物群落组成。本研究为指导温带典型草原的管理提供了有价值的信息。

关键词: 地上净初级生产力, 植物群落组成, 磷, 植物功能群, 温带典型草原