芒属植物能源潜力评价体系的构建

Construction of Energy Potential Evaluation System for Miscanthus

【目的】芒属植物是目前国内外生物质能源领域的研究热点,在全球共有14个种,且具有种间杂交的特点。文章为建立芒属植物能源潜力评价体系,为从众多的芒属基因型中筛选优良种质和选育能源作物品种奠定基础。【方法】通过文献法、调研法和专家咨询法探讨了芒属植物作能源作物应用的相关性状指标。运用层次分析法,根据能源用途不同按发电、制乙醇、产沼气、制生物油等4类,分别从农艺、品质、抗逆性等3方面,选取干物质产量、冠层高、茎高、茎径、基部直径、分蘖数、叶茎比、枯黄性、落叶性、含水量、灰分含量、挥发分含量、固定碳含量、热值、纤维素含量、半纤维素含量、木质素含量、矿质元素含量、耐盐性、抗旱性、抗寒性、耐淹性、抗病虫性等23项指标来构建芒属能源植物评价指标体系,同时制定了性状测量标准和能源利用潜力指数计算法则。然后使用该体系对湖南农业大学芒属植物资源圃中B0340(芒)、A0504(五节芒)、A0123(荻)、A0118(南荻)、D0302(奇岗)5个典型的芒属种质代表进行了测量和评价示范。再将评价结果与现有文献中有关发电、制乙醇和产沼气的能源理论产率计算公式的计算结果予以比对。【结果】芒属植物能源利用潜力指数分成4级,分别为极宜(75—100分)、适宜(50—74分)、一般(25—49分)、不宜(0—24分)。示范评价结果显示:A0504(五节芒)发电得60.73分,制乙醇得60.14分,产沼气得60.27分,制生物油得57.19分;A0118(南荻)发电得64.32分,制乙醇得58.45分,产沼气得58.20分,制生物油得60.01分;D0302(奇岗)发电得54.06分,制生物油得50.33分。可知A0504、A0118、D0302为适宜的能源植物,发酵制乙醇和沼气最适用A0504为原料,燃烧发电和热裂解制油最适用A0118为原料。此结果与现有文献中有关发电、制乙醇和产沼气的能源理论产率计算公式的计算结果基本一致,且比能源理论产率计算公式更能真实反映实际生产情况。【结论】通过从农艺、品质、抗逆性等3方面构建的芒属植物能源潜力评价体系,能够在发电、制乙醇、产沼气和制生物油4类能源用途方面客观评价芒属植物的适用性,从而可用于其优良种质的筛选和新品种的选育。

【Objective】Miscanthus（Miscanthus spp.） as a promising energy crop,nowadays research on it is a hot spot in the bioenergy field.Worldwide,there are 14 species in the Miscanthus genus and they can cross interspecies.The interspecific hybridization can create many natural hybrids,including some productive hybrids that can be directly used as commercial varieties.Screening productive natural hybrids is an efficient way to shorten the Miscanthus breeding process,however,prior to the screening process,a scientific energy potential evaluation system is required.【Method】The present work firstly summarized 23 traits that related to the energy potential（including the production potential of electric,ethanol,methane and bio-oil） of Miscanthus through literature survey,questionnaire investigation and expert consultation.They are：The agronomic traits including dry matter yield,canopy height,panicle height,stem diameter,base diameter,tillering number,leaf/stem ratio,senescence score,deciduous score;the energy quality traits including moisture content,ash content,volatile solid content,fixed carbon content,calorific value,cellulose content,hemicellulose content,lignin content,mineral element content;and the stress resistance traits including saline-alkali tolerance,drought resistance,cold resistance,submerge tolerance,disease and insect resistance.Based on these traits and using the analytic hierarchy process（AHP） method,a scientific energy potential evaluation system for Miscanthus was constructed.Besides,a measurement standard was draw up and a system to calculate the Miscanthus energy potential index was established.To show how this system work,energy potential of five typical Miscanthus germplsams collected from the Nursery Garden of Miscanthus Germplsams in Hunan Agricultural University were measured and evaluated.The five germplsams were：B 0340（Miscanthus sinensis）,A0504（Miscanthus floridulus）,A0123（Miscanthus sacchariflorus）,A0118（Miscanthus lutarioriparius） and D0302（Miscanthus × giganteus）.Their energy potentials in terms of power generation,ethanol and methane production were calculated and compared with precious results collected from literatures.【Result】Miscanthus energy potential index was divided into four levels：very suitable（75-100 points）,suitable（50-74 points）,general（25-49 points）,and unsuitable（0-24 points）.Through calculation,for the genotype of A0504,its power generation point（PGP） was 60.73,ethanol production point（EPP） of 60.14 and biogas production point（BPP） of 60.27,extract bio-oil point（EBP） of 57.19.For the genotype of A0118,its PGP,EPP,BPP,and EBP were 64.32,58.45,58.20 and 60.01,respectively.For the genotype of D0302,only its PGP（54.06） and EBP（50.33） were above the level of suitable.As can be seen,plants of A0504,A0118,and D0302 can be used as energy crop;Within,material of A0504（M.floridulus） is suitable for cellulosic ethanol and methane production,while biomass of A0118（M.lutarioriparius） is suitable for power generation and bio-oil extraction.These results are consistent with the evaluation results that calculated using the theoretical energy production yield formula.In addition,the evaluation system established in this study can more comprehensively evaluate the energy production potential than the calculated results by the theoretical yield formula.【Conclusion】Miscanthus energy potential evaluation system built from the agronomic,quality,resistance traits can objectively evaluate the suitability of Miscanthus in generate power,produce ethanol and methane,extract bio-oil.This evaluation system can provide a scientific guidance for Miscanthus germplsam selection and breeding of new varieties.