草地学报 ›› 2022, Vol. 30 ›› Issue (10): 2753-2763.DOI: 10.11733/j.issn.1007-0435.2022.10.026

• • 上一篇    

黄土丘陵区草地群落多样性和优势种养分对氮添加的响应

徐伟洲1,2, 赖帅彬2, 史雷1, 张艳珍1, 亢福仁1, 徐炳成2,3   

  1. 1. 榆林学院生命科学学院, 陕西 榆林 719000;
    2. 西北农林科技大学黄土高原土壤侵蚀与旱地农业国家重点实验室, 陕西 杨陵 712100;
    3. 中国科学院水利部水土保持研究所, 陕西 杨陵 712100
  • 收稿日期:2022-06-02 修回日期:2022-07-04 发布日期:2022-11-05
  • 作者简介:徐伟洲(1985-),男,博士,副教授,主要从事植被恢复与生态适应性研究,E-mail:wzxu@yulinu.edu.cn
  • 基金资助:
    国家自然科学基金项目(41701602);陕西省科技厅项目(2021KJXX-53)资助

Community Diversity and Dominant Species Nutrient Content of Grassland in Response to Nitrogen addition in Loess-Hilly Region

XU Wei-zhou1,2, LAI Shuai-bin2, SHI Lei1, ZHANG Yan-zhen1, KANG Fu-ren1, XU Bing-cheng2,3   

  1. 1. School of Life Sciences, Yulin University, Yulin, Shaanxi Province 719000, China;
    2. State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Northwest A&F University, Yangling, Shaanxi Province 712100, China;
    3, Institute of Soil and Water Conservation, Chinese Academy of Sciences and Ministry of Water Resources, Yangling, Shaanxi Province 712100, China
  • Received:2022-06-02 Revised:2022-07-04 Published:2022-11-05

摘要: 为探究大气氮沉降对黄土丘陵区草地群落多样性及其优势种生长的影响,本研究以白羊草(Bothriochloa ischaemum, Bi)和达乌里胡枝子(Lespedeza davurica, Ld)为优势种的草地群落为研究对象,设置3个氮添加处理(N0,0 kg ·hm-2·a-1;N25,25 kg ·hm-2·a-1;N75,75 kg ·hm-2·a-1),测定并分析了白羊草和达乌里胡枝子的株高、盖度、地上生物量(Aboveground biomass,AGB),物种多样性和养分含量。结果表明:氮添加处理下,Bi和Ld群落的总AGB显著提高;Bi群落中,氮添加显著降低物种多样性指数,而显著提高白羊草的全氮含量和氮磷比;Ld群落中,氮添加显著增加物种多样性指数,而显著降低达乌里胡枝子的全氮含量和氮磷比;相关性分析表明,物种多样性与白羊草的盖度和生物量呈显著负相关关系,与达乌里胡枝子的高度、盖度和AGB呈显著正相关。综上,氮添加促进了白羊草生长但抑制达乌里胡枝子,其群落优势种的AGB对物种多样性影响更加重要。

关键词: 氮添加, 物种多样性, 植物氮磷比, 地上生物量

Abstract: The aim of this study was to explore the effect of nitrogen (N) deposition on species diversity and the growth of dominant species in grassland ecosystems in the Loess Hilly-gully region. Two grassland communities with Bothriochloa ischaemum and Lespedeza davurica as the dominant species were studied by setting N main-plot:0 kg·hm-2·a-1;25 kg·hm-2·a-1 and 75 kg·hm-2·a-1. Plant height,coverage,aboveground biomass (AGB),species diversity,and nutrient content of grassland were analyzed for B. ischaemum and L. davurica. The results showed that N addition significantly increased the total AGB of B. ischaemum and L. davurica communities;In the B. ischaemum community,N addition significantly reduced the community species diversity,but significantly increased the total N content and N:P ratio of B. ischaemum;In the L. davurica community,N addition significantly increased their species diversity,but significantly increased the total N content and N:P ratio of L. davurica;Correlation analysis showed that species diversity was significantly negatively correlated with B. ischaemum cover and biomass,but was strongly positively correlated with height,coverage,and AGB of L. davurica. Therefore,N addition promoted the growth of B. ischaemum but inhibited the growth of L. davurica,and the AGB of the dominating species had a greater impact on diversity.

Key words: Nitrogen addition, Species diversity, N:P ratio in plants, Aboveground biomass

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