化石燃料儲量的減少及其勘探和燃燒過程會對環(huán)境產(chǎn)生不利影響,導(dǎo)致了對可再生能源生產(chǎn)需求的日益增加。中國在過去的二十年里國內(nèi)生產(chǎn)總值一直保持年均7%高速增長,而化石能源在推動人口占世界五分之一的中國經(jīng)濟(jì)發(fā)展中發(fā)揮著關(guān)鍵作用。據(jù)美國能源信息管理局的數(shù)據(jù)顯示,當(dāng)前中國能源消費(fèi)總量相比過去的十年增加了一倍多,尤其是石油消費(fèi)量位居于世界前列。中國的能源消耗主要以化石能源為主,尤其是煤。然而,基于化石能源燃料的使用會導(dǎo)致二氧化碳排放增加,會增加環(huán)境和人類的健康風(fēng)險。目前,中國政府一方面正努力通過限制煤炭的使用,另一方面鼓勵和促進(jìn)非化石燃料能源的開發(fā)利用,旨在促進(jìn)能源消費(fèi)多樣化以減少溫室氣體排放和大氣污染。為保障能源消費(fèi)安全,基于生物質(zhì)的能源開發(fā)利用為眾多可再生能源中最具前景之一。利用種植能源作物來生產(chǎn)生物燃料是可再生能源的巨大補(bǔ)充。然而,為保障中國的糧食安全,生物能源的發(fā)展前提是不與糧食作物的生產(chǎn)爭奪土地,且不能犧牲以生產(chǎn)谷物、油和糖料為基礎(chǔ)的糧食生產(chǎn)。由于中國耕地資源十分有限,利用邊際土地生產(chǎn)能源作物是一個最佳方案;此舉既可將發(fā)揮其作為生產(chǎn)生物燃料原料優(yōu)勢又能避免與糧食生產(chǎn)競爭。此外,能源作物普遍...

【文章頁數(shù)】：126 頁

【學(xué)位級別】：博士

【文章目錄】：
Abstract
摘要
List of Abbreviations
CHAPTER 1 General Introduction
    Background
    Objectives of the study
    Features and innovation of the study
    Review of Literature
        Bioenergy crops
        Energy sorghum
        Switchgrass
        Nitrogen rate management
        Phosphorus and potassium fertility management
        Biomass yield potential
        Crop nutrient uptake
        Nitrogen-use efficiency (NUE)
        Seasonal time of switchgrass harvest
        Biomass/forage quality
        Soil nitrogen budget and NO3
1-N accumulation
CHAPTER 2 Biomass yield and nutrient uptake of energy sorghum in response to nitrogen fertilizer rate on marginalland in a semi-arid region
    Introduction
    Materials and methods
        Study site
        Experimental design and crop husbandry
        Sampling, measurements, and chemical analysis
        Calculations and statistical analysis
    Results
        Temperature and rainfall in the growing seasons
        Effects of nitrogen rate, variety, and year
        Biomass yield and its partitioning
        N,P, and K concentration
        N,P, and K uptake and partitioning
        NUE
        N accumulation with respect to biomass yield
    Discussion
    Conclusion
CHAPTER 3 Short-term response of switchgass to nitrogen, phosphorus, and potassium on semiarid sandy wastelandmanaged for biofuel feedstock
    Introduction
    Materials and methods
    Results
        Growing season weather conditions
        Effects of the fertilizer treatments and variation among planting years
        Plant size and biomass yield
        Plant nutrient content and uptake
        Apparent N recovery and soil NO3
--N accumulation
        Relationship between soil available nutrients and plant parameters
    Discussion
    Conclusion
CHAPTER 4 Effects of nitrogen fertilization and harvest time on biomass yield and nutrient uptake of switchgassand soil nitrogen balance in a semiarid marginal land
    Introduction
    Materials and methods
        Study site
        Experimental design and crop management
        Sampling, measurements, and chemical analysis
        Calculations and statistical analysis
    Results
        Effects of nitrogen rate, harvest time, and year
        Plant size and biomass accumulation and partitioning
        Nutrient concentration and partitioning
        Nutrient uptake and partitioning
        N-use efficiency
        Apparent soil N balance
    Discussion
    Conclusion
CHAPTER 5 Effects of nitrogen rate and harvest time on switchgrass forage and biomass quality in semiarid marginalland
    Introduction
    Materials and methods
        Study site
        Experiment design and field operation
        Sampling and chemical analysis
        Calculations and statistical analysis
    Results
        Effects of nitrogen rate, harvest time, and year
        Quality components
        Theoretical ethanol yield (TEY)
        Soil NO3
--N content
    Discussion
    Conclusion
CHAPTER 6 General Conclusions
    Future research
REFERENCES
ACKNOWLEDGEMENTS
ABRIDGED RESUME



本文編號：3915661

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