Chin J Plant Ecol ›› 2021, Vol. 45 ›› Issue (6): 606-616.DOI: 10.17521/cjpe.2020.0268

• Research Articles • Previous Articles     Next Articles

Decomposition characteristics of leaf litters and roots of six main plant species and their relationships with functional traits in Stipa grandis steppe

ZHU Wei-Na1,3, ZHANG Guo-Long1,3, ZHANG Pu-Jin2, ZHANG Qian-Qian1,3, REN Jin-Tao1,3, XU Bu-Yun1,3, QING Hua1,3,*()   

  1. 1Inner Mongolia Key Laboratory of Grassland Ecology, School of Ecology and Environment, Inner Mongolia University, Hohhot 010020, China
    2Inner Mongolia Academy of Agricultural and Animal Husbandry Sciences, Hohhot 010031, China
    3Ministry of Education Key Laboratory of Ecology and Resource Use of the Mongolian Plateau, Inner Mongolia University, Hohhot 010020, China
  • Received:2020-08-06 Accepted:2020-12-23 Online:2021-06-20 Published:2021-09-09
  • Contact: QING Hua
  • Supported by:
    Natural Science Foundation of Nei Mongol of China(2018MS03072);National Natural Science Foundation of China(31960246);National Natural Science Foundation of China(31560174);Innovative Foundation of Nei Mongol Agricultural and Animal Husbandry Sciences(2020CXJJM11)

Abstract:

Aims It is very important to investigate the relationships between litter decomposition characteristics and plant functional traits in understanding the maintenance mechanism of ecosystem functions.

Methods In order to study the main driving factors that affect the leaf litters and root decomposition of different species, this study took the leaf litters and roots of six main plant species Stipa grandis, Cleistogenes squarrosa, Anemarrhena asphodeloides, Leymus chinensis, Convolvulus ammannii and Carex korshinskyi in S. grandis steppe. The litter bag method was used to study the decomposition rate constant of both leaf litters and root through 501 days of field incubation. Plant functional traits including leaf dry matter content, root specific surface area, root tissue density, contents of C, N and different cellulose components of the leaf and root litters were determined and the relationships between decomposition characteristics and functional traits of leaf litters and root across six plant species were examined.

Important findingsThe results showed that there were significant interspecific differences in leaf and root traits of six plant species. The ratios of maximum to minimum values for most traits were between 1 and 2, while the difference in some traits, such as C:N and specific surface area of roots between species was nearly 4 times. For the six plant species, the overall trend of the mass residue and decomposition rate constant of the leaf litter and root during 501 days of decomposition all showed the rapid decomposition in the early stage, relatively slow decomposition in the middle stage and the slowest decomposition in the later stage. During the decomposition process of leaf litters and roots, Cleistogenes squarrosa showed the slowest one, while the leaf litter decomposition of Anemarrhena asphodeloides was the fastest, and the root decomposition of Convolvulus ammannii was the fastest. Through the correlation analysis and stepwise regression analysis, it was found that the decomposition process of leaf litters and roots was affected by different traits in different decomposition periods. The structural carbohydrate content was the main factor affecting the early and late decomposition of litters and the early decomposition of roots, while the non-structural carbohydrate content was the main factor affecting the middle and late decomposition of roots. In addition, the decomposition rate of leaf litters in the middle stage of decomposition was mainly affected by leaf dry matter content, while the decomposition rates of roots in the middle and late stages of decomposition were also significantly affected by C:N and N content, respectively. Our results present the important guide for the prediction of carbon and nutrient cycling process in the S. grandis steppe.

Key words: Stipa grandis steppe, litter, plant functional trait, decomposition rate