Chin J Plant Ecol ›› 2022, Vol. 46 ›› Issue (11): 1364-1375.DOI: 10.17521/cjpe.2021.0491

• Research Articles • Previous Articles     Next Articles

Variation of functional traits of alternative distribution of Caragana species along environmental gradients in Nei Mongol, China

LUO Yuan-Lin1, MA Wen-Hong1,2,*(), ZHANG Xin-Yu1, SU Chuang1, SHI Ya-Bo1, ZHAO Li-Qing1,2   

  1. 1School of Ecology and Environment, Inner Mongolia University, Hohhot 010021, China
    2Key Laboratory of Ecology and Resource Use of Mongolian Plateau, Ministry of Education, Inner Mongolia University, Hohhot 010021, China
  • Received:2021-12-27 Accepted:2022-06-23 Online:2022-11-20 Published:2022-07-06
  • Contact: *MA Wen-Hong(whma@imu.edu.cn)
  • Supported by:
    The Special Foundation for National Science and Technology Basic Research Program of China(2015FY1103003);The Strategic Priority Research Program of Chinese Academy of Sciences(XDA26010101);The Science and Technology Major Project of Inner Mongolia(2021ZD0011)

Abstract:

Aims Trait-trait relationships and trait-environment relationships are critical for understanding species distribution, community assembly and plant strategy to environmental change. Caragana species distribute widely in arid Mongolia Plateau, and shape the alternative distribution along the environmental gradients. To understand the plant strategies to climate and soil, the trait-trait relationships and trait-environmental relationships were documented for Caragana species in Nei Mongol region.
Methods We measured eight morphological and chemical traits from nine Caragana species distributed across 41 sites in Nei Mongol, including plant height (h), leaf dry matter content (LDMC), specific leaf area (SLA), stem tissue density (STD), leaf area (LA), leaf nitrogen content (LNC), leaf phosphorus content (LPC), and leaf nitrogen to phosphorus ratio (N:P). We tested the trait-trait relationships between species and within species, and explored their relationships with aridity, soil nitrogen content and pH at the genus levels.
Important findings We found that the aridity index explained more than 29% of the variation in most functional traits (except N:P), with h, SLA, LA, LNC, and LPC decreased, while LDMC and STD increased with increasing drought. h, SLA, LDMC, STD and LNC were also affected by soil total nitrogen content. However, soil pH explained less for Caragana traits. The synchronous correlations or trade-offs among different functional traits were stronger at the genus level, while the trait-trait relationships within species were weak. There was a consistent increase in h, SLA, LA, LNC and LPC, but a decrease in LDMC and STD to declined aridity. We only observed significant correlations at the within-species level for C. korshinskii and C. microphylla, which were the most widely distributed. Plants with smaller distribution range have weak intraspecific covariation relationships among functional traits, which indicated that the plant economic spectrum theory is not necessarily suitable to explain the utilization of resources and the adaptation strategies of plants to environmental changes at the local scale at the individual level.

Key words: plant functional trait, trait covariation relationship, aridity index, soil nitrogen content, Caragana species