超声波处理对麦草碱木质素结构特性的影响   总被引：1，自引：0，他引：1  

任世学  方桂珍 《林产化学与工业》2005,25(10):82-86

采用超声波作用于麦草碱木质素，探讨了超声波对碱木质素的活化作用，用化学法对超声波作用前后碱木质素官能团进行了定量测定，用凝胶色谱（GPC）测定了木质素相对分子质量的变化，用^1H NMR光谱对化学结构进行了分析。结果表明：超声波可以显著提高碱木质素酚羟基和醇羟基含量，当作用时间20min、作用功率200w、液料质量比100：1时，醇羟基含量从1．99mmol／g上升为4．14mmol／g，酚羟基含量从1．88mmol／g上升为2．54mmol／g，羧基含量从0．59mmol／g下降为0．29mmol／g，羰基含量从2．16mmol／g上升为2．68mmol／g。^1H NMR分析表明，愈创木基和紫丁香基峰面积与总峰面积的比值分别从3．61％和0．77％下降为0，甲氧基峰面积与总峰面积的比值从11．50％下降为8．90％。数均分子质量（Mn）和重均分子质量（Mw）分别从1179和10250上升为5031和11605，分散度（Mw／Mn）从8．69下降为2．31．  相似文献   

Agroforestry on alkali soil: effect of planting methods and amendments on initial growth,biomass accumulation and chemical composition of mesquite (Prosopis juliflora (SW) DC) with inter-space planted with and without Karnal grass (Diplachne fusca Linn. P. Beauv.)     

Gurbachan Singh  I. P. Abrol  S. S. Cheema 《Agroforestry Systems》1988,7(2):135-160

Growth responses of mesquite (Prosopis juliflora (SW) DC.) during establishment stage to planting methods and amendments were studied in a highly alkali soil (Aquic Natrustalf, ESP 94), at the experimental farm of the Central Soil Salinity Research Institute, Karnal in July, 1984. Six combinations of planting methods and amendments with and without Karnal grass (Diplachne fusca Linn. P Beauv) in the inter-row space were compared in a four times replicated field experiment in randomised block design. The mean plant height (MPH), diameter at stump height (DSH), diameter at breast height (DBH), lopped biomass 16 months past planting and total biomass attained in 2 years period were significantly less when inter-row space was planted with Karnal grass. The MPH (cm), DSH and DBH (mm) attained in 2 years period were 319, 43.4 and 15.1 in with grass as compared to 405, 53.4 and 20.3 in without grass treatments. Similarly, the total biomass attained in 2 years was about 3 times more where inter-row space was not planted with grass. Growth was better when mesquite was planted by auger hole and pit methods than in trench plantation, when the original soil was treated with gypsum at 3 kg plant^–1 and then refilled. However, using trenches of dimensions 30 × 30 cm and filled with a mixture of original soil, 3 kg gypsum and 8 kg farm yard manure plant^–1 appeared to be promising method for establishing mesquite plantations on highly deteriorated alkali soils. The effect of amendments on growth decreased in the order gypsum + FYM, gypsum + rice husk, gypsum, control. In two years period, 37 percent mesquite died in the trenches in which the original soil was left unchanged. Effect of treatments on nutrient concentrations and total accumulations in different segments of mesquite is discussed. Karnal grass gave 25.3 t ha^–1 green forage yield in 8 cuts without amendment in a growth period of 26 months proving its great potential as a folder crop for the adverse sites. The inorganic chemical composition of the shoots, including trace elements Fe, Mn, Zn and Cu, is such as to make this species a highly promising plant for the exploitation of alkali soils. Growing Karnal grass with mesquite for a period of about 2 years reduced soil pH and EC significantly and improved organic carbon and available N contents. The grass improved water infiltration rates and moisture storage in the lower layers of the profile.  相似文献   

碱化灰漠土中小麦根际氮,磷元素动态变化初探   总被引：3，自引：2，他引：3  

马健  王周琼 《干旱区研究》1996,13(1):66-71

本文研究了碱化灰漠土中小麦根际土壤中氮、磷元素及其在不同生长期根际和非根际土壤中的动态变化。结果表明，与根际外土壤相比小麦根际微环境是一个变化活跃的区域。  相似文献   

黄土高原地区的生态建设与政策创新     

李胜利  赵景波  庞奖励 《干旱区资源与环境》2002,16(3):12-16

生态环境建设是西部大开发的根本切入点。黄土高原地区是我国生态环境最为严峻的地区 ,目前仍有 2 9万 km2 的土地有待治理 ,任务十分艰巨。本区生态环境建设的主要阻力是生态系统脆弱、经济系统贫困、科技文化水平落后、生态建设效益滞后、投资巨大等。提出的对策是稳定落实“退田还林”补贴政策 ,完善多元化的生态建设投资体系 ,建立公平合理的资源开发政策体系 ,加强生态环境建设的科技支撑作用 ,严格控制人口的快速增长等。强调排除阻力、促进生态环境建设的关键是调整思路 ,在各项政策和措施上都有所创新 ,有所突破  相似文献   

Growing fruit trees in highly alkali soils—a case study     

G. Singh  J. C. Dagar  N. T. Singh 《Land Degradation \u0026amp; Development》1997,8(3):257-268

The performance of 10 fruit species, namely pomegranate (Punica granatum), guava (Psidium guajava), sapota (Achras japota), baelpather (Aegle marmelos), amla (Emblica officinalis), ber (Zizyphus mauritiana), karaunda (Carissa carandas), date palm (Phoenix dactyleform), jamun (Syzygium cuminii) and imli (Tamarindus indica), as affected by site preparation and amendment use, was evaluated in a replicated field trial established in 1992 in a highly alkali soil (pH 10·5) at the Bichhian experimental farm of the Central Soil Salinity Research Institute, Karnal. The treatments involved two site preparation methods: (1) augerholes of 20–25 cm diameter and 160–180 cm deep made in the centre of 45 cm×45 cm pits in the main plot and (2) pits of 90 cm×90 cm×90 cm; variable amendments composition in the subplot and fruit species in the sub-subplots. Growth observations recorded 26 months after planting showed that survival, height and girth of all species remained unaffected owing to site preparation techniques and amendment use. Irrespective of planting techniques and amendment use, jamun, guava, ber and imli performed best. Date palm and baelpather performed poorly. Initial growth of sapota was satisfactory, but it was found highly sensitive to frost. Similarly, pomegranate which was performing exceedingly well was found very sensitive to prolonged water stagnation. This 3-year study indicated that out of 10 species tried, about half a dozen fruit plants can be established in alkali soils after following appropriate site preparation methods and better management practices. Established species came to bearing between 18 and 24 months after planting, but the fruits were damaged by prolonged water stagnation during the monsoon season and chilling temperatures of the 1994–95 winter. This study further indicated that the augerhole method of root bed preparation, is an economical, less laborious and faster way of planting fruit trees than is the pit method. The experiment will be continued to study treatment effects on fruit production and quality before making final recommendations. © 1997 John Wiley & Sons, Ltd.  相似文献   

菠萝叶可溶性膳食纤维碱法提取工艺的优化     

郭艳峰  李晓璐 《保鲜与加工》2019,19(5):104-108

以菠萝叶为原料,通过单因素及正交试验优化碱法提取菠萝叶可溶性膳食纤维的工艺条件。结果表明,碱法提取菠萝叶可溶性膳食纤维的最佳工艺为：料液比1∶60（g/mL）,NaOH碱液浓度20 mg/mL,浸提温度90 ℃,浸提时间2.0 h。在此工艺条件下,菠萝叶可溶性膳食纤维的提取率为9.48%。该提取工艺稳定性高,可节约能源,适于工业应用,为进一步开发高附加值产品奠定一定的基础。  相似文献   

生物炭与腐殖酸配施对盐碱土理化性质的影响   总被引：2，自引：0，他引：2  

韩剑宏  孙一博  张连科  王维大  李玉梅  孙鹏 《干旱地区农业研究》2020,38(6):121-127

为探索新型盐碱化土壤改良剂,选取玉米秸秆、葵花秸秆制成生物炭与腐殖酸配合,研究玉米秸秆生物炭（A）、混合秸秆生物炭（A₂1）、腐殖酸（B）、玉米秸秆生物炭+腐殖酸（AB）、混合秸秆生物炭+腐殖酸（A₂1B）5种改良剂与土壤混合后较对照组原土（CK）中盐碱指标、肥力指标的改善情况。结果表明：生物炭和腐殖酸都具有改良土壤盐碱性、提高土壤肥力的作用,二者联合配施对降低土壤pH、电导率（EC）、碱化度（ESP）及提高土壤养分的效果更明显,其中混合生物炭与腐殖酸配施（A₁B）效果最好,A₁B组处理的土壤pH较CK组显著降低10.8%,EC下降55%,ESP降低9.8%;速效钾、有效磷、速效氮及有机质的平均增幅较其他4个处理分别提升59.77%、210%、178%、180%。综上所述,混合施用生物炭及腐殖酸对于改良盐碱土效果明显。  相似文献   

Na2CO3对黄秋葵种子萌发及生理特性的影响     

曹亚萍  陈昭昱  王勇飞  贾孟君  贺嘉欣  张鑫瑞  李政  乔永刚  宋芸 《种子》2020,(3):24-28,33

为研究碱环境下黄秋葵种子萌发及生理特性,采用不同浓度(0、10、20、30、40 mmol·L^-1)Na2CO3溶液处理黄秋葵种子,测定其种子的萌发特性、胚根生长速度及第3天时胚根的生理特性。结果表明,随着碱浓度的增加,种子的发芽率、发芽势、发芽指数呈下降趋势,相对碱害率升高;发芽期间胚根长度与碱浓度呈负相关关系,且生长速度降低;碱胁迫下种子的抗氧化物酶(POD、CAT、SOD)活性较对照组无显著变化,MDA随碱浓度增加呈升高趋势,脯氨酸积累量变化不明显。发芽7 d后对照和10 mmol·L^-1碱液处理可萌发为幼苗,对其复水5 d后,发现10 mmol·L^-1处理侧根生长量远少于对照组。说明碱胁迫能抑制黄秋葵种子萌发及其幼苗生长,但黄秋葵种子对10 mmol·L^-1碱胁迫具有耐受性。  相似文献   

四种野生植物对天津盐碱地土壤改良效果的研究   总被引：2，自引：2，他引：0  

哈玲津  马媛媛  杨静慧 《北方园艺》2009,(4)

选择天津市蓟县、西青和大港的荒地土壤和耐盐碱的4种野生植物(猪毛菜、草木樨、艾蒿和补血草)进行盆栽试验.植株生长5个月后,测定土壤的各项理化指标.结果显示:4种植物均大大降低土壤总盐量,猪毛菜可以不同程度地降低土壤中CO23-、SO24-和有效磷;补血草对降低土壤SO24-和水溶性钙较有效;草木樨和艾篙可以明显增加土壤有效氮含量.综合分析表明,这4种野生耐盐植物对改良盐碱地土壤效果明显.  相似文献   

稻米直链淀粉含量的遗传及测定方法的改进   总被引：48，自引：1，他引：48  

申岳正  闵绍楷 《中国农业科学》1990,23(1):60-68

 本文提出一种简便易行的单粒稻米冷碱糊化直链淀粉含量测定法，即米粒不经磨粉、煮沸，只通过冷碱液直接糊化来测定直链淀粉含量。用此方法测得的直链淀粉含量与常规方法及小样米粉（20mg）冷碱糊化法测得的结果基本一致。用单粒稻米冷碱糊化法分析了7个组合后代的直链淀粉含量变化，结果表明：在高直链淀粉含量籼稻与高、低直链淀粉含量籼稻或糯稻的杂交组合中，高直链淀粉含量对低直链淀粉含量或糯性表现为完全显性，受单一显性基因控制，可能还受一些微效基因影响，并存在基因剂量效应；在低直链淀粉含量籼稻与糯稻的杂交组合中，直链淀粉含量的遗传可能受不同的Wx等位基因控制，也可能属数量遗传。  相似文献