|本期目录/Table of Contents|

[1]毛军 王长庭** 胡雷 字洪标.三江源区不同建植期禾草混播人工草地植物群落根系特征变化[J].应用与环境生物学报,2021,27(04):1-13.[doi:10.19675/j.cnki.1006-687x.2020.08006]
 MAO Jun,WANG Changting**HU Lei,ZI Hongbiao.Root dynamics of mixed artificial grasslands with different cultivation periods in the source region of Three Rivers in China *[J].Chinese Journal of Applied & Environmental Biology,2021,27(04):1-13.[doi:10.19675/j.cnki.1006-687x.2020.08006]
点击复制

三江源区不同建植期禾草混播人工草地植物群落根系特征变化()
分享到:

《应用与环境生物学报》[ISSN:1006-687X/CN:51-1482/Q]

卷:
27卷
期数:
2021年04期
页码:
1-13
栏目:
研究论文
出版日期:
2021-08-25

文章信息/Info

Title:
Root dynamics of mixed artificial grasslands with different cultivation periods in the source region of Three Rivers in China *
作者:
毛军 王长庭** 胡雷 字洪标
西南民族大学青藏高原研究院 成都 610041
Author(s):
MAO Jun WANG Changting**HU Lei ZI Hongbiao
Institute of Qinghai-Tibetan Plateau Research, Southwest Minzu University, Chengdu 610041, China
关键词:
人工草地建植期根系特征微根管
Keywords:
artificial grassland cultivation period root dynamics minirhizotron
DOI:
10.19675/j.cnki.1006-687x.2020.08006
摘要:
根系在植物生长和生物地球化学循环中扮演着重要的角色。为揭示不同建植期禾草混播人工草地植物群落根系特征的变化规律,以青海省果洛州玛沁县建植6、7、10和14年的人工草地为研究对象,利用“微根管”技术在2016年生长季(5-9月)原位监测了0-10、10-20和20-30 cm土层根系生长动态。结果显示:(1)根系生产、死亡和现存量分别在6-7、8-9和7-8月最高。(2)6-7月根系均为正生长(净生产速率为正值),8月开始出现负生长(净生产速率为负值)。(3)建植6-10年,0-10 cm土层根系形态特征指标(长度、表面积和体积)、累积生产量、平均现存量和寿命先增加后降低,但无显著差异(P > 0.05 );累积死亡量和周转率在建植6年显著高于10 a(P < 0.05 )。(4)建植14年,0-10 cm土层根系形态特征指标、累积生产量和平均现存量显著高于其他建植期,累积死亡量显著高于10年;20-30 cm土层累积生产量显著低于10年,周转率显著低于6年。同时,0-10 cm和10-20 cm土层根系存活率最高。(5)根系形态特征指标、累积生产量、累积死亡量和平均现存量在建植6、7和14年随土层深度的增加而显著下降,10年时则变化不明显。(6)Pearson相关性分析表明,土层和根系形态特征指标分别与寿命极显著正相关(P < 0.01 );建植期与周转率显著负相关(P < 0.05 ),土层、根系表面积、体积和寿命分别与周转率极显著负相关;结构方程模型(SEM)进一步分析显示,建植期对根系长度具有显著正效应,对周转率具有显著负效应,周转率还受表面积、寿命和土层的直接影响。综上,恢复14年人工草地0-10 cm土层根系生长和累积量明显提高,建植年限的延长对周转率具有负效应,因此,长期恢复后人工草地地下碳循环速率下降,养分积累量增加,群落稳定性和生态系统生产、生态服务功能逐步恢复。(图5 表3 参62)
Abstract:
Roots play an important role in plant growth and biogeochemical cycles. These experiments explore the temporal dynamics of root characteristics in mixed artificial grasslands of different ages (6, 7, 10, and 14 years old) in the region of China near the source of the Three Rivers. Minirhizotrons were used to observe root growth dynamics of the 0-10 cm, 10-20 cm, and 20-30 cm soil layers during the growing season (May-September) in 2016. Measured root variables include morphology, productivity, and lifespan. The results showed that: (1) In all stands, root production was highest June to July, mortality was highest August to September, and standing standing crop peaked July to September. (2) Root systems showed positive growth from June to July (net production rate > 0), and negative growth (net production rate < 0) occurred in August. (3) Root morphological characteristics (length, surface area and volume), cumulative production, mean standing crop and root lifespan of 0-10 cm soil layer first increased and then decreased during years 6-10 of grassland cultivation, but differences were, overall, not significant (P > 0.05). Cumulative mortality and turnover were significantly higher in 6 years old plots than in the 10 years old ones ( P < 0.05). (4) After 14 years of restoration, root morphological characteristics, cumulative production and mean standing crop in 0-10 cm soil layer were significantly higher than earlier, and cumulative mortality was significantly higher than at 10 years. In these oldest plots, cumulative production of the 20-30 cm soil layer was significantly lower than at 10 years, and root turnover was significantly lower than at 6 years. Meanwhile, root survival rate was the highest in 0-10 cm and 10-20 cm soil layers. (5) Root morphological characteristics, cumulative production, mortality and mean standing crop decreased significantly with the increase of soil depth for the 6, 7, and 14 years old plots, but there were no significant differences at 10 years. (6) Pearson correlation analysis showed that soil layers and root morphological characteristics were significantly positively correlated with lifespan (P < 0.01). Cultivation periods was significantly negatively correlated with turnover ( P < 0.05). Soil layers, root surface area, volume and lifespan were significantly negatively correlated with turnover. Structural equation model (SEM) further analysis showed that cultivation periods had a significant positive effect on the root length and a significant negative effect on the turnover. Turnover was also directly affected by root surface area, lifespan, and soil depth. In conclusion, root growth and accumulation of 0-10 cm soil layer were significantly increased when the artificial grassland was restored in 14 years, and the cultivation period had a negative effect on root turnover. Therefore, after long-term restoration, the underground carbon circulation rate of artificial grassland decreased, nutrient accumulation increased. Over time, community stability, ecosystem production and ecological service functions were gradually restored.

相似文献/References:

[1]王启兰,王长庭,刘伟,等.江河源区人工草地植物群落和土壤酶活性变化[J].应用与环境生物学报,2010,16(05):662.[doi:10.3724/SP.J.1145.2010.00662]
 WANG Qilan,WANG Changting,LIU Wei,et al.Changes in Plant Communities and Soil Enzyme Activities of Artificial Grasslands in Headwater Areas of the Yangtze and Yellow Rivers[J].Chinese Journal of Applied & Environmental Biology,2010,16(04):662.[doi:10.3724/SP.J.1145.2010.00662]
[2]杨希智,王长庭,字洪标,等.三江源区不同建植年限人工草地土壤微生物群落结构特征[J].应用与环境生物学报,2015,21(02):341.[doi:10.3724/SP.J.1145.2014.10033]
 YANG Xizhi,WANG Changting,ZI Hongbiao,et al.Soil microbial community structure characteristics in artificial grassland with different cultivation years in the headwater region of Three Rivers, China[J].Chinese Journal of Applied & Environmental Biology,2015,21(04):341.[doi:10.3724/SP.J.1145.2014.10033]
[3]欧延升,汪霞,李佳,等.不同恢复年限人工草地土壤碳氮磷含量及其生态化学计量特征[J].应用与环境生物学报,2019,25(01):38.[doi:10.19675/j.cnki.1006-687x.2018.05005]
 OU Yansheng,WANG Xia**,LI Jia,et al.Content and ecological stoichiometry characteristics of soil carbon, nitrogen, and phosphorus in artificial grassland under different restoration years[J].Chinese Journal of Applied & Environmental Biology,2019,25(04):38.[doi:10.19675/j.cnki.1006-687x.2018.05005]

备注/Memo

备注/Memo:
收稿日期 Received: 2020-08-03 接受日期 Accepted: 2020-10-12
国家重点研发计划(2019YFC0507701)、第二次青藏高原综合科学考察研究项目(2019QZKK0302)、国家自然科学基金项目(31870407)、四川省重点研发项目(2018SZ0333)、中央高校基本科研业务费专项资金 (2020NZD03)和西南民族大学研究生“创新型科研项目”重点项目(CX2019SZ86)资助
**通讯作者 Corresponding author (E-mail: wangct@swun.edu.cn or wangct6@163.com)
本文为已录用的作者修定稿,尚未经编辑全面修改。
引用本文请注明出处本刊;发表刊期和页码将以正式出版时的安排为准,但DOI确定不变。
更新日期/Last Update: 2020-11-06