ISWC OpenIR  > 水保所2018--2019届毕业生论文
氮磷添加对内蒙古草原植物-土壤系统碳氮分布特征的影响
方昭
Subtype硕士
2019-05-22
Degree Grantor中国科学院水利部水土保持研究所
Place of Conferral陕西省咸阳市杨凌区水土保持研究所
Degree Name工程硕士
Keyword内蒙古草原 氮磷添加 生物量 化学计量特征 碳氮分配特征
Abstract

本研究以内蒙古地区3种草原类型区草地群落为研究对象,研究不同气候条件下草地群落生物量、化学计量特征及其碳氮分布规律对氮磷添加的响应差异,旨在为全球变化背景下我国退化草地恢复和治理工作提供理论基础和建议,同时也为准确分析与预测氮沉降背景下草地碳源汇变化和碳收支提供科学依据及基础资料。主要结果如下:

1)内蒙古草地群落结构和物种组成较为简单,其物种科属种分布较为分散,物种多样性和群落生产力沿东北-西南方向样带整体呈现先降低后上升的变化趋势,3种草原类型区物种多样性指数整体无显著差异(P>0.05),而草甸草原群落生产力显著高于典型草原和荒漠草原(P<0.05)。相关分析结果表明气候因子和土壤条件对内蒙古自然植被物种多样性和生产力均有显著影响。草地群落生产力与物种丰富度、多样性指数均呈线性正相关。

2)氮磷添加对内蒙古草原各站点草地群落生物量(地上、地下生物量和总生物量)都具有促进作用,其生物量变化比例均随氮磷添加水平呈现先上升后下降的变化趋势。不同氮磷添加水平对草甸(8.22%38.44%)和荒漠草原(14.72%54.38%)草地群落地上生物量的促进作用均高于典型草原(4.18%19.18%)。地下生物量对氮磷添加的响应整体比地上生物量小,其中N添加对草甸(6.99%27.32%)和典型草原(22.9%41.83%)地下生物量的促进作用高于荒漠草原(2.29%18.28%),对典型草原(3.81%21.20%)和荒漠草原(10.98%35.15%)总生物量的促进作用高于草甸草原(1.18%10.93%);而不同P添加水平对典型草原(24.72%53.84%5.58%27.38%)和荒漠草原(27.94%49.49%17.21%41.19%)地下生物量和总生物量的促进作用均高于草甸草原(-1.39%19.72%-8.82%11.41%)。沿经度梯度下各站点草地群落地上生物量主要与氮磷添加水平和降雨量呈正相关关系,而地下生物量和总生物量主要与磷添加水平和干旱系数呈正相关关系,三者均与温度呈负相关关系。

3)在群落水平上,不同N添加水平下荒漠草原(4.03%22.04%)群落N/P增加比例高于草甸草原(-0.48%10.93%)和典型草原(-0.38%14.51%),而群落C/NC/P变化比例在3种草原类型间相差不大。随施氮水平的升高,草甸草原和荒漠草原群落N/P逐渐增加,群落C/N逐渐减小,而群落C/P变化趋势不显著(P>0.05);而典型草原各站点化学计量比无显著变化趋势。不同土层土壤化学计量比对N添加水平变化趋势大致相同,其中,3个草原类型区0-10cm10-30cm土壤C/NN添加水平呈下降趋势,土壤N/P呈现先上升后下降的变化趋势,而C/P则变化趋势不显著(P>0.05)。不同P添加水平下3种草原类型群落C/N变化比例相差不大,而群落C/P-41.31%-19.99%)和N/P-43.16%-27.72%)下降比例以荒漠草原最大,而草甸草原和典型草原较为接近。随施磷水平的升高,群落C/N逐渐增加,而群落C/PN/P逐渐下降。3种草原类型0-10cm10-30cm土壤C/PN/P均随P添加水平呈显著下降趋势,而C/NP添加水平变化趋势不显著(P>0.05)。

4)氮磷添加对经度梯度下各站点草地群落生物量碳氮库都有提升作用,其生物量碳氮库变化比例均随氮磷添加水平的增加而增加。不同N添加水平对典型草原地上生物量碳氮库的促进比例弱于草甸和荒漠草原,而草甸和典型草原地下生物量碳氮库和总生物量碳氮库的变化比例均高于荒漠草原。而不同P添加水平对荒漠草原地上生物量碳氮库的促进比例高于草甸和典型草原,典型草原地下生物量碳氮库和总生物量碳氮库的促进比例高于草甸和荒漠草原。不同氮磷添加水平对不同土层土壤碳氮库的促进作用整体较弱,其中荒漠草原不同土层土壤碳氮库变化比例均小于草甸和典型草原。不同氮磷添加水平下草甸草原草地群落地上活体碳库/根系碳库下降比例最大,荒漠草原地上活体氮库/根系氮库增加比例最大。不同N添加水平下草甸草原碳氮元素在地上活体-土壤和根系-土壤组分间的增加比例大于典型和荒漠草原。不同P添加水平下荒漠草原地上活体-土壤间氮分配增加比例最大,草甸草原根系-土壤间的氮分配比例增加最大。

Other Abstract

In this study, three grassland types in Inner Mongolia were used as research objects to study the differences in the response of biomass, stoichiometry and carbon and nitrogen distribution of grassland communities to nitrogen and phosphorus addition under different climatic conditions. The theoretical basis and suggestions for the restoration and treatment of degraded grassland are provided, and the scientific basis and basic data for the accurate analysis and prediction of grassland carbon source and sink change and carbon budget in the background of nitrogen deposition are provided. The main conclusions are as follows:

  (1) The community structure and species composition of grassland in Inner Mongolia are relatively simple. The distribution of species, families and species is dispersed. The species diversity and community productivity show a trend of decreasing first and then increasing along the northeast-southwest transect. There is no significant difference in species diversity index among the three grassland types (P>0.05), while the productivity of meadow steppe community is significantly higher than that of typical steppe and desert steppe. The results of correlation analysis show that climate factors and soil conditions have significant effects on the species diversity and productivity of natural vegetation in Inner Mongolia. The productivity of grassland community was positively correlated with species richness and diversity index.

(2) Nitrogen and phosphorus addition promoted grassland community biomass (aboveground and underground biomass and total biomass) at all stations in Inner Mongolia grassland, and the proportion of biomass change increased first and then decreased with the level of nitrogen and phosphorus addition. The above-ground biomass of meadow (8.22%38.44%) and desert grassland (14.72%54.38%) was higher than that of typical grassland (4.18%19.18%). The response of underground biomass to nitrogen and phosphorus addition was smaller than that of aboveground biomass. Among them, N addition promoted the underground biomass of meadow steppe (6.99%27.32%) and typical steppe (22.9%41.83%) higher than that of desert steppe (2.29%18.28%), and promoted the total biomass of typical steppe (3.81%21.20%) and desert steppe (10.98%35.15%) higher than that of meadow steppe (1.18%10.93%). The effects of different P addition levels on underground biomass and total biomass of typical steppe (24.72%53.84%; 5.58%27.38%) and desert steppe (27.94%49.49%; 17.21%41.19%) were higher than those of meadow steppe (-1.39%19.72%); -8.82%11.41%). The above-ground biomass of grassland communities along the longitude gradient was positively correlated with nitrogen and phosphorus addition level and rainfall, while the belowground biomass and total biomass were positively correlated with phosphorus addition level and drought coefficient, all of which were negatively correlated with temperature.

(3) At the community level, the increase of N/P ratio in desert steppe (4.03%22.04%) was higher than that in meadow steppe (-0.48%10.93%) and typical steppe (-0.38%14.51%) at different N addition levels, while the change ratio of C/N and C/P in community was not significantly different among the three steppe types. With the increase of nitrogen application level, N/P of community in meadow steppe and desert steppe increased gradually, C/N of community decreased gradually, but the change trend of C/P of community was not significant (P>0.05), while the stoichiometric ratio of each site in typical steppe did not change significantly. The change trend of soil stoichiometric ratio of different soil layers was similar. The C/N of 0-10 cm and 10-30 cm soils in three grassland types showed a downward trend with the N addition level, while the N/P of soils increased first and then decreased, while the C/P of soils showed no significant change trend (P>0.05). The C/N ratio of three grassland types had little difference under different P addition levels, while the C/P (-41.31%19.99%) and N/P (-43.16%27.72%) decreased the most in desert steppe, while the meadow steppe and typical steppe were close. With the increase of phosphorus application level, community C/N increased gradually, while community C/P and N/P decreased gradually. C/P and N/P in 0-10 cm and 10-30 cm soil of three grassland types decreased significantly with P addition level, but C/N did not change significantly with P addition level (P>0.05).

(4) Nitrogen and phosphorus addition could enhance the carbon and nitrogen pools of grassland community biomass under longitude gradient, and the change proportion of carbon and nitrogen pools of grassland community biomass increased with the increase of nitrogen and phosphorus addition level. The promotion ratio of aboveground biomass carbon and nitrogen pools in typical grassland was weaker than that in meadow and desert steppe, while the change ratio of belowground biomass carbon and nitrogen pools and total biomass carbon and nitrogen pools in meadow and typical steppe was higher than that in desert steppe. The promotion ratio of aboveground biomass carbon and nitrogen pool in desert steppe was higher than that in meadow and typical steppe, and the promotion ratio of belowground biomass carbon and nitrogen pool and total biomass carbon and nitrogen pool in typical steppe was higher than that in meadow and desert steppe. The effects of different nitrogen and phosphorus levels on soil carbon and nitrogen pools in different soil layers were weaker, and the change ratio of soil carbon and nitrogen pools in different soil layers in desert steppe was smaller than that in meadow and typical steppe. Under different nitrogen and phosphorus levels, the aboveground living carbon pool/root carbon pool of grassland community in meadow steppe decreased the most, while the aboveground living nitrogen pool/root nitrogen pool in desert steppe increased the most. Carbon and nitrogen in meadow steppe increased more than those in typical steppe and desert steppe at different levels of N addition. Under different P levels, the N allocation between aboveground living organisms and soil in desert steppe increased the most, while that between root system and soil in meadow steppe increased the most.

MOST Discipline Catalogue工学::环境科学与工程(可授工学、理学、农学学位)
Table of Contents

     

目 录

第1章 绪论......................................................................................................................... 1

  1.1选题的背景及意义.................................................................................................... 1

  1.2国内外研究现状与进展............................................................................................ 1

  1.3 研究内容及目标....................................................................................................... 6

第2章 材料与方法............................................................................................................ 7

  2.1 研究区概况............................................................................................................... 7

  2.2 实验设计................................................................................................................... 8

  2.3 研究方法................................................................................................................... 9

  2.4 技术路线................................................................................................................. 12

第3章 不同草原类型区植被物种多样性、生产力变化及其环境解释................... 13

  3.1 不同草原类型区草地群落物种多样性和生产力的变化.................................. 13

  3.2 不同草原类型区草地群落物种多样性、生产力变化的影响因素................. 13

  3.3 草地群落物种多样性与群落生产力的关系...................................................... 18

  3.4 讨论......................................................................................................................... 19

  3.5 小结......................................................................................................................... 21

第4章 氮磷添加对不同草原类型区草地群落生物量的影响................................... 23

  4.1 氮添加对不同草原类型区草地群落生物量的影响.......................................... 23

  4.2 磷添加对不同草原类型区草地群落生物量的影响.......................................... 26

  4.3 植物生物量氮磷添加效应比较................................................................... ....... 28

  4.4 小结......................................................................................................................... 30

第5章 氮磷添加对不同草原类型区植物群落和土壤生态化学计量比的影响 ......32

  5.1 氮添加对不同草原类型区草地植物群落化学计量比的影响.......................... 32

  5.2 磷添加对不同草原类型区草地土壤化学计量比的影响.................................. 39

  5.3 植物群落和土壤生态化学计量特征的氮磷添加效应比较.............................. 47

  5.4 小结......................................................................................................................... 49

第6章 氮磷添加对不同草原区植物群落和土壤碳氮分配特征的影响................... 51

  6.1 氮添加对不同草原类型区植物-土壤系统碳氮分配特征的影响.................... 51

  6.2 磷添加对不同草原类型区植物-土壤系统碳氮分布特征的影响................... 59

  6.3 讨论......................................................................................................................... 67

  6.4 小结.......................................................................................................................... 70

第7章 总结及展望.......................................................................................................... 72

  7.1 主要结论................................................................................................................. 72

  7.2 展望......................................................................................................................... 73

参考文献....................................................................................................... .................. 75

致谢................................................................................................................................... 81

作者简介及攻读硕士学位期间发表的学术论文与研究成果.................................... 83

Pages83
Language中文
Document Type学位论文
Identifierhttp://ir.iswc.ac.cn/handle/361005/8792
Collection水保所2018--2019届毕业生论文
Recommended Citation
GB/T 7714
方昭. 氮磷添加对内蒙古草原植物-土壤系统碳氮分布特征的影响[D]. 陕西省咸阳市杨凌区水土保持研究所. 中国科学院水利部水土保持研究所,2019.
Files in This Item:
File Name/Size DocType Version Access License
2019届硕士毕业论文—方昭.pdf(3800KB)学位论文 开放获取CC BY-NC-SAApplication Full Text
Related Services
Recommend this item
Bookmark
Usage statistics
Export to Endnote
Google Scholar
Similar articles in Google Scholar
[方昭]'s Articles
Baidu academic
Similar articles in Baidu academic
[方昭]'s Articles
Bing Scholar
Similar articles in Bing Scholar
[方昭]'s Articles
Terms of Use
No data!
Social Bookmark/Share
All comments (0)
No comment.
 

Items in the repository are protected by copyright, with all rights reserved, unless otherwise indicated.