欢迎访问《草业学报》官方网站,今天是 分享到:

草业学报 ›› 2025, Vol. 34 ›› Issue (2): 41-53.DOI: 10.11686/cyxb2024126

• 研究论文 • 上一篇    下一篇

碳、氮、钾添加对荒漠草原凋落物分解特征的影响

骆欣怡1,2,3,4(), 邱开阳1,2,3,4(), 金涛5, 鲍平安1,2,3,4, 黄业芸1,2,3,4, 何毅1,2,3,4, 谢应忠1,2,3,4   

  1. 1.宁夏大学林业与草业学院,宁夏 银川 750021
    2.宁夏草牧业工程技术研究中心,宁夏 银川 750021
    3.农业农村部饲草高效生产模式创新重点实验室,宁夏 银川 750021
    4.盐池北部荒漠草原宁夏野外科学观测研究站,宁夏 银川 750021
    5.宁夏贺兰山国家级自然保护区管理局,宁夏 银川 750021
  • 收稿日期:2024-04-18 修回日期:2024-06-05 出版日期:2025-02-20 发布日期:2024-11-27
  • 通讯作者: 邱开阳
  • 作者简介:E-mail: kaiyangqiu@nxu.edu.cn
    骆欣怡(2000-),女,甘肃天水人,在读硕士。E-mail: 873956269@qq.com
  • 基金资助:
    中国科学院“西部之光”人才培养计划项目和中国人力资源和社会保障部高层次留学人才回国资助项目(人社厅函 [2019]160号)资助

The effects of carbon, nitrogen, and potassium addition on the decomposition characteristics of litter in desert grasslands

Xin-yi LUO1,2,3,4(), Kai-yang QIU1,2,3,4(), Tao JIN5, Ping-an BAO1,2,3,4, Ye-yun HUANG1,2,3,4, Yi HE1,2,3,4, Ying-zhong XIE1,2,3,4   

  1. 1.College of Forestry and Grassland,Ningxia University,Yinchuan 750021,China
    2.Ningxia Grassland and Animal Husbandry Engineering Technology Research Center,Yinchuan 750021,China
    3.Key Laboratory of Innovation in Efficient Grass Production Models of the Ministry of Agriculture and Rural Affairs,Yinchuan 750021,China
    4.Ningxia Field Scientific Observation and Research Station on Desert Grassland in the North of Yanchi,Yinchuan 750021,China
    5.Ningxia Helan Mountains National Nature Reserve Administration,Yinchuan 750021,China
  • Received:2024-04-18 Revised:2024-06-05 Online:2025-02-20 Published:2024-11-27
  • Contact: Kai-yang QIU

摘要:

凋落物分解是草地生态系统能量流动和物质循环的重要过程,而荒漠草原凋落物分解如何响应碳(C)、氮(N)、钾(K)添加尚不清楚,揭示这一关系对深入理解荒漠草原养分循环过程具有重要意义。本研究选用网袋分解法,进行随机区组设计,在试验样地分别设置C1 (0 g·m-2·a-1)、C2 (52.54 g·m-2·a-1)、C3 (705.09 g·m-2·a-1);N1 (0 g·m-2·a-1)、N2 (5 g·m-2·a-1)、N3 (20 g·m-2·a-1);K1 (0 g·m-2·a-1)、K2 (9.0 g·m-2·a-1)、K3 (18.0 g·m-2·a-1) 3个C、N、K浓度梯度,研究外源C、N、K添加对宁夏荒漠草原优势种短花针茅和赖草凋落物分解特征的影响。结果表明:1)C、N、K添加对荒漠草原两个物种凋落物分解的影响具有显著差异(P<0.05),短花针茅和赖草凋落物分解速率进程不同,分别在分解至120和240 d时,分解速率开始减缓;2)不同物种对C、N、K养分添加的响应不同。K3、K3+N3+C2处理下赖草凋落物分解速率较快,但CK、K2+N2处理下短花针茅凋落物分解速率较快。依据指数衰减模型预测分解速率结果为:赖草>短花针茅;3)短花针茅和赖草凋落物均在秋季分解较快。综上,同一生境不同物种凋落物分解速率存在差异,高添加量的K、N和低添加量的C相较于其他养分添加梯度,对凋落物分解速率的促进作用更明显。

关键词: 荒漠草原, 凋落物, 分解特征, 养分添加

Abstract:

Decomposition of litter is an important component process of energy flow and material cycling in grassland ecosystems. However it is not clear how litter decomposition in desert grasslands responds to the addition of carbon (C), nitrogen (N), and potassium (K). Clarification of this relationship is needed to improve our understanding of the nutrient cycling process in desert grasslands. In this study, the mesh bag decomposition method was used in a randomized block design, to study the effects of exogenous C, N, and K addition on the litter decomposition characteristics of the dominant species Stipa breviflora and Leymus secalinus in Ningxia desert grassland. Litter decomposition was tested in soils fertilized with one of three rates of C (vermicompost, 30% C), N (urea, 46% N) or K (KCl, 60% K) as follows: C1 (0 g·m-2·yr-1), C2 (52.54 g·m-2·yr-1) and C3 (705.09 g·m-2·yr-1) set at the experimental site; along with nutrient addition treatments. N1 (0 g·m-2·yr-1), N2 (5 g·m-2·yr-1) and N3 (20 g·m-2·yr-1), three C, N, and K concentration gradients, K1 (0 g·m-2·yr-1), K2 (9.0 g·m-2·yr-1) and K3 (18.0 g·m-2·yr-1). It was found that significant differences in the effects of C, N, and K addition on litter decomposition and different decomposition rates of litter from S. breviflora and L. secalinusP<0.05). Half-lives for L. secalinus decay ranged from 4.93 to 17.54 months and for S. breviflora from 10.76 to 20.51 months. The decomposition rates of litter from S. breviflora and L. secalinus began to slow down at 120 and 240 days, respectively. Leaves of the two grass species displayed different responses to the addition of C, N, and K nutrients. Under the K3 and K3+N3+C2 treatments, the decomposition rate of L. secalinus litter was faster, while under the CK and K2+N2 treatments, the decomposition rate of S. breviflora litter was faster. According to the exponential decay model, the predicted decomposition rate for L. secalinus litter is greater than for S. breviflora litter. The litter of both L. secalinus and S. breviflora decomposed quickly in autumn. In summary, there were differences in litter decomposition rates of the two grass species in the same habitat, and high additions of K and N and low additions of C promoted litter decomposition rates more strongly than other nutrient addition combinations.

Key words: desert grassland, litter, decompose features, nutrient addition