| 黄土高原天然草地 3 种优势物种细根分解及养分释放对模拟氮沉降的响应 |
| 魏琳1,3; 程积民1,2; 井光花1,3; 赵洁2; 苏纪帅2; 刘建2
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| 2018
|
发表期刊 | 水土保持学报
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卷号 | 32期号:1页码:252-258 |
摘要 | 细根分解是草地土壤有机质和养分的主要来源,全球 N 沉降背景下细根分解动态变化对生态系统
碳和养分循环具有重要意义。采用埋袋法研究黄土高原天然草地3个优势物种细根分解速率和养分释放
规律及其对模拟 N沉降( 10g · N /( m
2 · a ))的响应。结果表明:细根分解过程分为快速(
0~60d )和慢速
分解( 60~719d )
2 个阶段。大针茅、甘青针茅和白莲蒿细根分解 60d 的质量残留率分别为 86.3% ,
86.2% , 90.7% ,分解 719d 的质量残留率分别为 58.1% , 64.7% , 70.5% ,表明细根分解速率大小为大针
茅 > 甘青针茅 > 白莲蒿。相关分析表明,细根分解常数与细根初始 N 含量、 N / P 值呈显著的正相关关系,
与初始 C 含量、 C / N 值呈显著的负相关关系。随着根系分解, 3 种细根 C 元素表现为直接释放, N 元素表
现为 N富集, P元素表现为富集-释放模式,整体呈波动式下降。模拟 N沉降显著抑制了3种植物细根的
分解,使大针茅、甘青针茅和白莲蒿细根分解系数分别显著降低了21.3% , 26.8% , 47.4% 。模拟 N沉降使
大针茅、甘青针茅和白莲 蒿 分 解 末 期 C 元 素分 别 增 加 了 26.8% , 20.7% , 16.6% , N 元素分别增加了
18.2% , 17.0% , 13.4% ,而对 P 残留率均没有显著影响。综上,未来氮沉降的增加会抑制黄土高原封育草
地优势物种的细根分解速率,减慢其细根分解向土壤输入 C 和 N 养分的过程。 |
其他摘要 | Fine root decomposition is the main source of soil organic matter and soil nutrients in grasslands.
Fine root decomposition dynamics under the background of global nitrogen deposition plays an important role
in carbon and nutrient cycling of terrestrial ecosystem.In this study , buried bag
experiment was used to in -
vestigate fine root decomposition rate and nutrient release characteristics of three dominant grass species on
the Loess Plateau , and their response to nitrogen deposition (
10g
N /( m
2 · a ))
.The results showed that the
decomposition process of fine roots could be divided into rapid ( 0~60d ) and slow ( 60~719d ) decomposi -
tion stages.The root mass residual rates of Stipagrandis , Stipaprzewalskyi and Artemisia
sacrorum were
86.3% , 86.2%and 90.7%on the 60th day , respectively , and they were 58.1% , 64.7%and 70.5%on the
719th day , respectively , indicating
that the fine roots decomposition of S . grandis was the fastest and it ofA . sacrorum was the lowest.Correlation analyses showed that the decomposition constant of fine roots was
positively related with nitrogen content and N
/ P ratio , and negatively
correlated with the carbon content and
C / N ratio.During the fine root decomposition , the carbon transfer models of the three species were all
direct releasing , and the nitrogen transfer models were enriching ,
and phosphorus exhibited enriching - relea -
sing
model , and all of them tended to decrease generally.Simulated nitrogen deposition suppressed the fine
root decomposition rates of S . grandis , S . przewalskyi and A . sacrorum , with the decomposition constants
decreased by 21.3% , 26.8%and 47.4% ,
respectively.While , it increased the carbon remaining rates of S .
grandis , S . przewalskyi and A . sacrorum
by
26.8% , 20.7% and 16.6% , respectively , and increased
nitrogen remaining rates by
18.2% , 17.0%and 13.4%at the end of our study period.However , phosphor -
us remaining rates of fine roots in all three species were not significantly
influenced by simulated nitrogen
deposition.Nitrogen deposition in the future will inhibit the fine roots decomposition rates of the three
dominant species in fenced grassland on the Loess Plateau , and slow down the process of inputting carbon
and nitrogen from plant into soil. |
关键词 | 草地
细根分解
养分释放
N 沉降
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收录类别 | 中文核心期刊要目总览
|
语种 | 中文
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文献类型 | 期刊论文
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条目标识符 | sbir.nwafu.edu.cn/handle/361005/10257
|
专题 | 水保所知识产出(1956---)
|
作者单位 | 1.中国科学院水利部水土保持研究所 2.西北农林科技大学动物科技学院 3.中国科学院大学
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第一作者单位 | 中国科学院水利部水土保持研究所
|
推荐引用方式 GB/T 7714 |
魏琳,程积民,井光花,等. 黄土高原天然草地 3 种优势物种细根分解及养分释放对模拟氮沉降的响应[J]. 水土保持学报,2018,32(1):252-258.
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APA |
魏琳,程积民,井光花,赵洁,苏纪帅,&刘建.(2018).黄土高原天然草地 3 种优势物种细根分解及养分释放对模拟氮沉降的响应.水土保持学报,32(1),252-258.
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MLA |
魏琳,et al."黄土高原天然草地 3 种优势物种细根分解及养分释放对模拟氮沉降的响应".水土保持学报 32.1(2018):252-258.
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文件名:
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黄土高原天然草地3种优势物种细根分解及养分释放对模拟氮沉降的响应_魏琳.pdf
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格式:
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Adobe PDF
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