氮添加和凋落物管理对中国北方半干旱草原羊草养分再吸收的综合影响。

Combined effects of nitrogen addition and litter manipulation on nutrient resorption of Leymus chinensis in a semi-arid grassland of northern China.

机构信息

Institute of Grassland Science, Key Laboratory of Vegetation Ecology, Northeast Normal University, Ministry of Education, Changchun, China.

出版信息

Plant Biol (Stuttg). 2015 Jan;17(1):9-15. doi: 10.1111/plb.12172. Epub 2014 Mar 25.

Abstract

Plant growth in semi-arid ecosystems is usually severely limited by soil nutrient availability. Alleviation of these resource stresses by fertiliser application and aboveground litter input may affect plant internal nutrient cycling in such regions. We conducted a 4-year field experiment to investigate the effects of nitrogen (N) addition (10 g N·m(-2) ·year(-1)) and plant litter manipulation on nutrient resorption of Leymus chinensis, the dominant native grass in a semi-arid grassland in northern China. Although N addition had no clear effects on N and phosphorus (P) resorption efficiencies in leaves and culms, N fertilisation generally decreased leaf N resorption proficiency by 54%, culm N resorption proficiency by 65%. Moreover, N fertilisation increased leaf P resorption proficiency by 13%, culm P resorption proficiency by 20%. Under ambient or enriched N conditions, litter addition reduced N and P resorption proficiencies in both leaves and culms. The response of P resorption proficiency to litter manipulation was more sensitive than N resorption proficiency: P resorption proficiency in leaves and culms decreased strongly with increasing litter amount under both ambient and enriched N conditions. In contrast, N resorption proficiency was not significantly affected by litter addition, except for leaf N resorption proficiency under ambient N conditions. Furthermore, although litter addition caused a general decrease of leaf and culm nutrient resorption efficiencies under both ambient and enriched N conditions, litter addition effects on nutrient resorption efficiency were much weaker than the effects of litter addition on nutrient resorption proficiency. Taken together, our results show that leaf and non-leaf organs of L. chinensis respond consistently to altered soil N availability. Our study confirms the strong effects of N addition on plant nutrient resorption processes and the potential role of aboveground litter, the most important natural fertiliser in terrestrial ecosystems, in influencing plant internal nutrient cycling.

摘要

在半干旱生态系统中,植物的生长通常受到土壤养分供应的严重限制。通过施肥和地上凋落物输入来缓解这些资源压力,可能会影响这些地区植物内部的养分循环。我们进行了为期 4 年的野外实验,研究了氮(N)添加(10 g N·m(-2)·year(-1))和植物凋落物处理对中国北方半干旱草地优势乡土草本植物羊草(Leymus chinensis)养分再吸收的影响。尽管氮添加对叶片和茎中的氮和磷(P)再吸收效率没有明显影响,但氮施肥通常会使叶片氮再吸收效率降低 54%,茎氮再吸收效率降低 65%。此外,氮施肥会使叶片 P 再吸收效率提高 13%,茎 P 再吸收效率提高 20%。在环境或富氮条件下,凋落物添加降低了叶片和茎中的氮和磷再吸收效率。凋落物处理对磷再吸收效率的响应比氮再吸收效率更敏感:在环境和富氮条件下,随着凋落物量的增加,叶片和茎中的磷再吸收效率均显著降低。相比之下,除了环境氮条件下的叶片氮再吸收效率外,凋落物添加对氮再吸收效率没有显著影响。此外,尽管凋落物添加在环境和富氮条件下都会导致叶片和茎养分再吸收效率普遍降低,但凋落物添加对养分再吸收效率的影响远小于凋落物添加对养分再吸收效率的影响。总之,我们的研究结果表明,羊草的叶片和非叶片器官对土壤氮供应的变化有一致的反应。我们的研究证实了氮添加对植物养分再吸收过程的强烈影响,以及地上凋落物(陆地生态系统中最重要的天然肥料)在影响植物内部养分循环方面的潜在作用。

文献AI研究员

20分钟写一篇综述,助力文献阅读效率提升50倍

立即体验

用中文搜PubMed

大模型驱动的PubMed中文搜索引擎

马上搜索