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利用高产牧草柳枝稷生产清洁生物质能源的研究进展 总被引：11，自引：10，他引：1
介绍了柳枝稷Panicum virgatum生物学特性和近年来国内外利用其生产清洁生物质能源--燃料乙醇的研究现状,阐述了柳枝稷原料预处理和进行发酵生产燃料乙醇的工艺过程.研究表明,由于低地型柳枝稷生产力高,作为转化燃料乙醇的专门能源植物极有潜力;球磨预处理、酶解和稀酸结合预处理柳枝稷对于发酵转化燃料乙醇效果显著.转化柳枝稷木质纤维素效率高的工程菌主要有重组肠杆菌Escherichia coli、运动发酵单孢菌Zymomonas mobilis、酿酒酵母Saccharomyces cerevisiae.重组肠杆菌的基因重组菌株KO11,能将葡萄糖和木糖发酵为乙醇,乙醇产率为理论值的103%～106%.酿酒酵母的重组工程菌种E2在木糖培养液中厌氧转化木糖效率达1.1 g/(g·h).对柳枝稷燃料乙醇生命周期分析发现,柳枝稷燃料乙醇短期内能够减少57%温室气体排放.在我国利用柳枝稷生产燃料乙醇是一种可行的清洁能源产业,能够同时起到改善生态环境,优化农业和草业产业结构的作用. 相似文献
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生物能源植物柳枝稷简介 总被引：16，自引：5，他引：11
概述了柳枝稷Panicum virgatum作为生物能源的研究现状,柳枝稷是分布于中美洲和北美洲的一种多年生草本植物,20世纪90年代后国际上将其作为一种新型能源模式作物进行了深入研究,用于火力发电,或以木质纤维素生产乙醇.其种植成本低,生长迅速,植株可高达2m,最高产量可达74t/hm2,高产期可持续15年,对环境适应性强.柳枝稷木质纤维素含量极高,其乙醇转化率可达到57%.火力发电废气排放量少,燃烧充分.种植柳枝稷可给种植户带来巨大的经济效益.在我国推广柳枝稷,既可作为饲草,也可作为水土保持和风障植物,同时也是很好的生物燃料和生产替代能源的原材料. 相似文献
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纤维素类能源草在京郊地区的经济效益与生态价值评价 总被引：5，自引：2，他引：3
纤维素类能源草是一类重要的能源植物与良好的生物质资源。对柳枝稷、荻、芦竹3种纤维素类能源草从农业种植到纤维素乙醇制备的整个过程进行了经济效益与生态价值的初步评价,结果表明,以柳枝稷、荻、芦竹为原料,每制备1.00 t纤维素乙醇的经济效益分别为4 147.85,1 185.08,2 019.76元,柳枝稷最优,芦竹次之,荻再次之;每制备1.00 t纤维素乙醇所需种植的柳枝稷、荻、芦竹的大气净化生态价值分别为4 639.28,4 351.25,4 320.39元,柳枝稷最优,荻次之,芦竹再次之;3种纤维素类能源草均具有强大的固定大气CO2的能力,对于降低温室气体CO2浓度、促进土壤碳的积累具有积极作用。 相似文献
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为了探究镉污染条件下开发能源植物的可行性,以高生物量黍属能源植物柳枝稷和坚尼草为材料,温室中苗期水培试验,分别对柳枝稷外源施加浓度为0,0.5,5,10,20,50,100μmol/L镉(Cd),对坚尼草施加浓度为0,2,5,7.5,10μmol/L Cd,从形态、生长生理等角度,分析两种能源草对镉的响应。结果表明:随Cd浓度的增加,柳枝稷和坚尼草生物量和根伸长量均下降,Cd浓度为50μmol/L时,柳枝稷根鲜重减少达显著水平(P0.05)。而坚尼草则在Cd浓度为2μmol/L时,根和地上部分总鲜重减少达显著水平。相比于对照,Cd浓度为2μmol/L时,坚尼草的根伸长量已下降96.3%,而柳枝稷在5μmol/L Cd时根伸长量才降低55.0%,柳枝稷的耐镉性高于坚尼草。经20μmol/L镉处理,柳枝稷的地上部镉浓度达40mg/kg,生物量下降了45%。不同浓度的镉处理下,镉在柳枝稷体内的迁移指数为5.9%~14.2%,柳枝稷可以在Cd污染条件下被开发为能源和修复植物种植。此外,实验还发现,在根平均直径为0~1mm范围内,柳枝稷的总根长、根表面积和根体积与镉积累呈显著负相关,与迁移指数呈显著正相关(P0.05),该结果说明,细根在植物的镉吸收积累和转运中可能起着非常重要的作用。 相似文献
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柳枝稷(Panicum virgatum L.)存在苗期生长缓慢的现象,而菌根真菌与植物共生可以促进植物生长。为了探究菌根真菌对柳枝稷苗期生长的影响,我们以来自于柳枝稷低地型品种Alamo的2个品系Ma和Mg为材料,诱导丛枝菌根真菌(Arbuscular mycorrhizal fungi,AMF)与柳枝稷共生,研究丛枝菌根真菌对柳枝稷苗期生长的影响及其分子机制。结果表明:丛枝菌根真菌可以侵入苗期柳枝稷根的内部形成共生菌根,并显著增加柳枝稷苗期的叶绿素含量、株高、叶片数和生物量。寄生植物瓜列当(Orobanche aegyptiaca)种子萌发和独脚金内酯(Strigolactones,SLs)合成标记基因检测实验表明,丛枝菌根真菌与柳枝稷共生可以抑制柳枝稷根系合成独脚金内酯,进而解除独脚金内酯对柳枝稷分蘖的抑制作用,促进柳枝稷苗期的生长。 相似文献
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草产品在畜牧生产中的应用 总被引：3，自引：0，他引：3
本文阐述了草产品及其种类、加工方式及生产意义，以及主要生产应用的牧草种类与养畜生产中草产品的应用，就其生产特性、营养水平及行业发展前景提出了自己的看法和建议。 相似文献
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Lotka-Volterra数学模型在草地管理中的应用 总被引：1，自引：1，他引：0
介绍了Lotka-Volterra数学模型建立、求解方法,详细讨论了该模型在草地生态系统中的应用特点。通过分析认为可以利用Lotka-Volterra模型调控草地生态系统中载畜量与草地牧草产量间的关系,从而准确指导草地畜牧业生产。 相似文献
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生物质能源在燃料生产与发电方面的应用现状与前景 总被引：6，自引：0，他引：6
生物质能源替代传统性能源已成为人类研究的一项热门课题。概述了生物质能源的发生历程,综述了国内外利用生物质能源转化生产乙醇、柴油、石油等燃料物质以及利用生物质气化、联介循环、作物秸秆燃烧来发电的一些应用现状。我国对于生物质能源的发展前景将着眼于如何合理地充分利用本国的地理优势及丰富的物种资源来作为生物质能源,我国生物质能源的发展方向应该是把农、林、草三位一体化,将草业学科与生物技术等一些学科相互结合,创造出低成本又环保,且节省资源,为社会带来巨大经济效益的生物质能源物质。 相似文献
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柴达木盆地家畜舍饲育肥综合效益评价 总被引：1，自引：1，他引：0
在柴达木盆地推广使用地产饲草料舍饲育肥家畜具有良好的效益和前景，畜均纯收益分别为成牛244，25元、犊牛317．82元、藏成羊71．7元、半细毛成羊58.01元、藏羔羊34．61元、半细毛羔羊40.69元；按一个农村劳动力饲喂10头成牛和40只成羊、每年育肥两次（折合180个羊单位）计，纯收益可达1．3万元，以推广3000户计算，可降低天然草地载畜量30×10^4羊单位，减少天然草地放牧压力20％。 相似文献
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6种能源草的丛枝菌根侵染状况初步调查 总被引：1，自引：0，他引：1
共生是植物适应环境的一种重要策略,丛枝菌根真菌作为一类古老的土壤微生物,能与陆地上大多数的维管植物形成专性共生体系,在影响植物生长发育、养分吸收和生态适应性等方面起到了关键作用。对栽培于中国农业大学涿州试验站的6种能源草（8个品种）进行菌根侵染状况和孢子群落的初步调查,结果表明：所有能源草类型均能被AM真菌侵染并形成丛枝、泡囊、菌丝等典型结构,侵染水平为4.3%~25.2%,其中虉草（Phalaris arundinacea）侵染率最高,芒草（Miscanthus sinensis）最低。每20 g根际土中有18.7~48.0个孢子,菌丝密度在1.8~4.2 m·g-1之间。经过对根外孢子的形态学鉴定,发现与调查的能源草共生的AM真菌优势种类为Funneliformis mosseae和Claroideoglomus etunicatum。这表明丛枝菌根真菌能与本研究中的能源草建立良好的共生关系,为能源草的生态适应性研究提供了新的思路。 相似文献
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Effect of short-duration overnight cattle kraaling on grass production in a southern African savanna
Pamela Sibanda Edward Mufandaedza Mukai Mawanza 《African Journal of Range and Forage Science》2016,33(4):217-223
Ranch owners in eastern and southern Africa have embraced a new rangeland management practice of keeping cattle overnight in temporary livestock corrals (hereafter referred to as kraals) within rangelands for short durations (for example, one week) to improve grass production. To better understand the influence of this practice on the grass community, we determined grass species diversity, richness, biomass and quality (crude protein, fibre, rumen fermentation and metabolisable energy) from a chronosequence consisting of kraals abandoned 1, 2, 3 and 4 years prior to the study and compared them to the surrounding vegetation. Grass species diversity, richness, biomass and quality were higher in abandoned kraals than the surrounding vegetation. Grass biomass increased five-fold in the first year of kraal abandonment and thereafter declined three-fold after four years. Metabolisable energy, a measure of grass nutritive value, increased from 8.92 to 11.90 MJ kg?1 with kraaling. The number of grass species also increased with kraaling. Palatable grass species, such as Urochloa mosambicensis and Panicum maximum, were more abundant in abandoned kraal sites than the surrounding vegetation. We conclude that short-duration overnight cattle kraaling improves grass quality and biomass. 相似文献
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B. Hipp K.‐H. Südekum A. Zeyner G. Goren E. Kienzle 《Journal of animal physiology and animal nutrition》2018,102(1):e380-e386
The prediction of renal energy excretion is crucial in a metabolizable energy system for horses. Phenolic acids from forage cell walls may affect renal energy losses by increasing hippuric acid excretion. Therefore, the relationships were investigated between renal energy, nitrogen (N) and hippuric acid excretion of four adult ponies (230–384 kg body weight (BW)) consuming diets based on fresh grass, grass silage, grass cobs (heat‐dried, finely chopped, pressed grass), alfalfa hay, straw, extruded straw and soybean meal. Feed intake was measured; urine and faeces were quantitatively collected for three days. Feed was analysed for crude nutrients, gross energy, amino acids and neutral‐detergent‐insoluble crude protein (CP); faeces were analysed for crude nutrients and cross energy; urine was analysed for N, hippuric acid, creatinine and gross energy. Renal energy excretion (y; kJ/kg BW0.75) correlated with renal N excretion (x1; g/kg BW0.75) and renal hippuric acid excretion (x2; g/kg BW0.75): y = 14.4 + 30.2x1+20.7x2 (r = .95; n = 30; p < .05). Renal hippuric acid excretion was highest after intake of fresh grass and lowest after intake of soybean meal. The ratio of hippuric acid to creatinine in urine and the excretion of hippuric acid per gram of dry matter intake was significantly higher for fresh grass than for all other rations. There was no relationship between aromatic amino acid intake and renal hippuric acid excretion. The results of the present study and literature data suggest that feed can be categorized into four groups with regard to the energy losses per gram CP intake: (i) protein supplements (e.g., soybean meal): 4.2–4.9 kJ/g CP intake (ii) alfalfa hay, grains, dried sugar beet pulp: 6.4 kJ/g CP intake, (iii) hay, preserved grass products, straw: 5.2–12.3 kJ/g CP intake (mean 8) and (iv) fresh grass. For group (iii) a negative relationship was observed between renal energy losses per gram of CP and the content of CP or neutral‐detergent‐insoluble CP in dry matter. 相似文献
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用鸭茅、猫尾草、无芒雀麦、紫花苜蓿、红三叶、红豆草建植多年生混播草地,混播草地种类为5种豆禾牧草混播、6种豆禾牧草混播,豆∶禾混播比例分别为3∶7和2∶8。依据建植第1年(2013年)和第2年(2014年)的牧草产量、牧草营养物质产量和消化能产出,以使役马(中型)、使役马(重型)、妊娠马(妊娠11个月)和泌乳马(产驹后3个月均值)营养物质和消化能需求为评价准则,采用营养物质和消化能"产出-需求相对差额"法对几种豆禾混播组合的生产性能进行评价。结果表明:以使役马(中型)、妊娠马营养物质和消化能需求为评价准则,豆∶禾为3∶7的混5组合(紫花苜蓿+红豆草+鸭茅+猫尾草+无芒雀麦)生产性能最高;以使役马(重型)、泌乳马营养物质和消化能需求为评价准则,豆禾比3∶7的另一混5组合(紫花苜蓿+红三叶+鸭茅+猫尾草+无芒雀麦)生产性能最高。 相似文献
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A.J.H. Van Es 《Livestock Production Science》1974,1(1):21-32
It is argued that in view of the many new methods in dairy farming an economic model of the dairy farm should be available to improve advisory work. Some quantitative data concerning the dairy cow needed for such a model are given. They deal with a net energy feeding value of grass, hay, silage, artificially dried grass and concentrates estimated with a feed evaluation system based on results obtained with lactating cows. Also data on the requirements for net energy and for long forage dry matter are given, again obtained with such cows. Finally information is given on voluntary intake of forage dry matter at pasture, from fresh grass fed indoors, from various preserved forages including forage pellets, as influenced by milk yield and condition of the cow and by kind of forage and level of concentrates fed. Special attention has been paid to the precision of the information. These data are used to predict both the maximal and minimal amounts of long forage which can be fed in the stall period without loss of production, and the additional quantities of concentrates needed. For the grazing cow the problem of the adjustment of voluntary intake of grass to milk yield and amount of concentrates fed is studied. It is concluded that the information is sufficient to develop an economic model of a dairy farm. For its development grassland research should supply data on pasture yield in terms of digestible organic matter when the forage is fed to sheep at the maintenance level, and the economists should add data on costs of food and labour. 相似文献