中国科学院生态环境研究中心机构知识库
Advanced  
RCEES OpenIR  > 城市与区域生态国家重点实验室  > 学位论文
题名: 施肥及秸秆还田对中国农田土壤固碳、温室气体排放及粮食产量的影响
作者: 赵红
学位类别: 博士
答辩日期: 2015-05
授予单位: 中国科学院研究生院
授予地点: 北京
导师: 王效科
关键词: 施肥 ; 秸秆还田 ; 固碳 ; 温室气体排放 ; 产量,Fertilization ; straw incorporation ; greenhouse gas emission ; cereal yield
其他题名: Impacts of fertilization and straw incorporation on soil carbon storage, greenhouse gas emissions and cereal yield in Chinese croplands
学位专业: 生态学
中文摘要:       作为目前全球最大温室气体排放国和人口大国,中国面临着农田土壤退化和粮食安全的双重威胁,而土壤有机碳是土壤肥力的核心,所以迫切需要探求有效的措施来 提高我国的碳储量和粮食产量。施肥和秸秆还田不仅是我国目前提高粮食生产的重要农作措施,也是《京都议定书》中认可的固碳减排途径。因此科学估算施肥及秸 秆还田对我国农田的固碳减排潜力,提出与施肥和秸秆还田搭配合理的农作措施对我国“藏粮于土”计划及全球减排谈判有着重要意义。本文以国内典型长期定位试 验数据为研究基础,采用Meta分析方法定量分析对不同情况下施肥和秸秆还田对中国农田土壤碳储量、温室气体排放及产量的影响。探讨有效的与施肥和秸秆还 田配合措施,并估算出不同情况下我国农田土壤的固碳、减排及增产潜力。主要成果如下:
      (1)相对于不施肥,施肥可显著提高农田土壤的有机碳储量,施肥总体上对稻田甲烷排放无显著影响,降低旱地甲烷吸收达15%,增加全球增温潜力 (global warming potential, GWP) 78%,且显著增产91%。施肥对农田固碳、温室气体排放及产量的影响受试验地区、轮作措施及试验年限等因素的限制。在西北和华北土壤基础养分较低的农区 中施肥固碳和增产效果好于基础养分较高的东北和南方农区。总体来讲,氮肥对农田固碳和增产的贡献高于磷肥,磷肥又高于钾肥。相对于不施肥,少量施肥可促进 稻田甲烷排放(50-100 kg N ha–1),而多量施肥可抑制甲烷排放(200-250 kg N ha–1)。玉米(Zea mays)田和小麦(Triticum aestivum)田的氧化亚氮排放因子分别为1.00和0.94%,而稻田(Oryza sativa)氧化亚氮排放因子较低(0.51%)。施肥增加的GWP表现为旱地高于稻田。当前的施肥情况我国每年可固碳33.2 Tg C,按固碳角度优化施肥后,我国农田每年可固碳56.17 Tg C。而按优化氮肥利用率的角度优化施肥,我国农田每年可减排GWP达-3.99–4.37 Tg CO2-C eqv yr–1。
      (2)相对于不施秸秆,秸秆还田可显著提高中国农田的碳储量,显著增加稻田甲烷排放105%,减少甲烷吸收11%,增加旱田(3-27%)及降低稻田氧化 亚氮排放(4-23%),且每年增产0.8%。秸秆还田量、还田类型、轮作制度、试验地区及试验年限均显著影响固碳、温室气体排放及增产水平。在经历耕作 及较严重碳流失的地区(东北和西北地区)进行长期大量的粉碎秸秆还田更利于土壤固碳。秸秆还田后,甲烷排放量从高到低依次为中稻>晚 稻>早稻,且与秸秆的碳氮比呈正相关。而相对于秸秆直接还田,腐熟的秸秆导致较高的旱地氧化亚氮排放。秸秆还田增加的GWP表现为稻田高于 旱地。秸秆还田后,西北和华北地区的增产水平高于东北和南方。在缺水及较低土壤养分的地区施加秸秆的增产水平高于初始养分较高的地区,尤其是水稻-水稻轮 作中增产较少。秸秆还田每增加1 kg ha–1的土壤有机碳储量可增产44 kg ha–1。单季和双季秸秆全部还田每年分别可固碳57.77和64.29 Tg C yr-1,增排143.97和181.82 Tg CO2-C eqv yr–1,及增产406.91和482.49万t yr-1。
      (3)在当前的实际施肥水平下,中国农田为净增排14.68 Tg CO2-C yr–1,而采取优化施肥后每年不仅净减排达11.57 Tg C,还可增加0.88亿吨粮食产量。单季秸秆还田和双季秸秆全部还田情景下我国农田的净增排分别为86.23和119.33 Tg CO2-C eqv yr–1,其中华北、东北、及西南地区秸秆还田后可有效减排,减排潜力在4.95至12.37 Tg CO2-C eqv yr–1之间,而由于秸秆还田显著增加稻田甲烷排放,以水稻为主的种植区表现为净增排,增排潜力在80.77至103.84 Tg CO2-C eqv yr–1之间。从全国尺度来看,单季和双季秸秆还田的增温潜势分别为固碳量的2.48和2.83倍。
       因此,未来我国农田应科学确定最优施肥量,而不同地区秸秆还田应区别对待,因地制宜。旱田中秸秆可直接还田即可达到增产减排作用,而稻田中应施加碳氮比较 低的沼渣还田,以确保稻田土壤的固碳和减排。
英文摘要:       As the world’s most greenhouse gas (GHGs) emissions and populous country, China confronts with priority two challenges of soil degradation and food safety. Soil organic carbon (SOC) is the core of soil fertilizer, therefore, available measures are needed for improving the SOC storage and food production in China. Synthetic fertilizer application (SF) and straw incorpiration (SI) are the important measures for yield increment, simultaneously, are also the mitigation approach recognized by the Kyoto Protocol. Hence, scientific evaluations on soil carbon sequestration potentials of SF and SI, and raising sound measure combined with SF and SI are of important significance for the plan of storing food in land and diplomatic issues of mitigation. Based on the typical long-term experimental data, Meta-analysis method was applied for quantitative analysis the impacts of SF and SI on SOC storage, GHGs, and cereal yield under different circumstances. The favorable agricultural measures were discussed in sequestrating SOC storage, reducing GHGs emissions, and yield increasing, and estimating the potential of sequestrating carbon, GHGs mitigation, and yield increment under different SF and SI situations. The results as follows.
      (1) Comparing with no fertilizer, SF could significantly improve the SOC storage in Chinese croplands, the responses of CH4 emissions to SF in rice paddies overall no effects were found, reduced methane (CH4) uptake in upland fields 15% increased global warming potential (GWP) of CH4 and nitrous oxide (N2O) emissions by 78%. The influences of experimental regions, cropping systems and experimental durations should all be considered, when assessing the SOC storage, GHGs emissions and yield increase induced by SF. SF-induced carbon sequestration and cereal yield increases were greater in areas with a lack of soil nutrients (north and northwest) than the areas rich of soil nutrient (northeast and south). Overall, the contribution of carbon sequestration and yield increase were higher in nitrogen fertilizer application, than phosphate fertilizer and potassium fertilizer. CH4 emissions were stimulated at low N application rates (50-100 kg N ha–1) but inhibited at high N rates (200-250 kg N ha–1) as compared to no fertilizer. The mean N2O emission factors were 1.00 and 0.94% for maize (Zea mays) and wheat (Triticum aestivum), but significantly lower for the rice (Oryza sativa) (0.51%). SF-induced GWP was higher in upland fields than rice paddies. In the current SF situation, SOC sequestration potential is 33.2 Tg C yr-1, after optimized fertilization from C sequestration, SOC sequestration potential is 55.17 Tg C yr-1. After optimized fertilization from nitrogen use efficiency, GWP mitigations could reach to 11.03 and 17.76 Tg CO2-C eqv yr–1.
      (2) Comparing with no SI, SI could significantly increase SOC storage in Chinese cropland, significantly increase CH4 emission in rice paddies 121%, reduced CH4 uptake 11%, stimulate N2O emission in uptland soil (3-27%), but inhibit N2O emission in rice paddies, and enhance cereal yield 7% across the 9-year period. SI effects on SOC storage, GHGs emission and yield are highly dependent on the type and amount of straw, cropping system, experimental region, and duration of SI. The application of larger chopped straw amounts over a longer duration was more favorable to soil C sequestration, especially the soils experiencing with serious C loss (northwest and northeast regions). After implementation of SI, CH4 emission level was medium rice > late rice > early rice, and significantly positive with C/N ratio of straw. Comparing with direct SI, compost SI could stimulate N2O emission in upland soils. SI-induced GWP was higher in rice paddies than upland fields. SI-induced cereal yield increases were higher in north and northwest regions than northeast and south regions. Addtionally, SI-induced cereal yield increases were greater in the areas with a lack of soil nutrients and soil water than rich of soil nutrients areas, especially the rice-rice rotation showed the lower yield increase. SI increases of 1 t ha–1 of SOC storage could increase cereal yield by 44 kg ha–1. Single and double SI across all of China’s agricultural regions, soil C sequestration potential could reach 57.77 and 64.29 Tg C yr–1, increase emission 143.97 and 181.82 Tg CO2-C eqv yr–1, and yields increase 4.07 and 4.82 million tonnes per year, respectively.
      (3) In current SF level, Chinese croplands’ net mitigation emission is –14.68 Tg CO2-C yr–1, after implemention of opmized SF, the annual net mitigation emission potential could reach 11.57 Tg CO2-C eqv yr–1, and increase 88 million tonnes cereal yields. The net GHGs increase in single SI and double SI are 86.23 and 119.33 Tg CO2-C eqv yr–1, however, SI could reduce GHGs emissions in north, northeast, and southwest region, mitigation potential is between 4.95 and 12.37 Tg CO2-C eqv yr–1, while due to the increasing of CH4 emission after implementation of SI in rice paddies, the primary rice growing area showed net increase of GHGs, increasing potential is between 80.77 and 103.84 103.84 g CO2-C eqv yr–1. From the natioal scale, the GWP of single and double SI is 2.48 and 2.83 folds higher than SOC sequestration potential.
      Hence, we should change SF amount in the future, operation of SI should adopted the policies of discriminatory and according to local conditions. SI could reduce emissions in upland soils, while in rice paddies, biogas residue return should be considered, for ensuring the SOC sequestration and mitigation in China.
内容类型: 学位论文
URI标识: http://ir.rcees.ac.cn/handle/311016/34543
Appears in Collections:城市与区域生态国家重点实验室_学位论文

Files in This Item:
File Name/ File Size Content Type Version Access License
赵红--施肥及秸秆还田对中国农田土壤固碳、温室气体排放及粮食产量的影响.pdf(4391KB)学位论文--限制开放 联系获取全文

Recommended Citation:
赵红. 施肥及秸秆还田对中国农田土壤固碳、温室气体排放及粮食产量的影响[D]. 北京. 中国科学院研究生院. 2015.
Service
Recommend this item
Sava as my favorate item
Show this item's statistics
Export Endnote File
Google Scholar
Similar articles in Google Scholar
[赵红]'s Articles
CSDL cross search
Similar articles in CSDL Cross Search
[赵红]‘s Articles
Related Copyright Policies
Null
Social Bookmarking
Add to CiteULike Add to Connotea Add to Del.icio.us Add to Digg Add to Reddit
所有评论 (0)
暂无评论
 
评注功能仅针对注册用户开放,请您登录
您对该条目有什么异议,请填写以下表单,管理员会尽快联系您。
内 容:
Email:  *
单位:
验证码:   刷新
您在IR的使用过程中有什么好的想法或者建议可以反馈给我们。
标 题:
 *
内 容:
Email:  *
验证码:   刷新

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

 

 

Valid XHTML 1.0!
Copyright © 2007-2018  中国科学院生态环境研究中心 - Feedback
Powered by CSpace