固体栽培基质研究、开发现状及发展趋势

随着无土栽培和穴盘育苗技术的广泛应用,固体基质的需求量日益增大,基质市场迅速壮大,栽培基质的开发和应用已成为重要的研究领域.该文在分析栽培基质应用和市场前景的基础上,综述了国内外栽培基质材料开发、基质合成、性状研究与改良的现状,及已取得的主要成果和存在的问题,指出了栽培基质今后的发展趋势.     

固体栽培基质研究、开发现状及发展趋势

随着无土栽培和穴盘育苗技术的广泛应用，固体基质的需求量日益增大，基质市场迅速壮大，栽培基质的开发和应用已成为重要的研究领域。该文在分析栽培基质应用和市场前景的基础上，综述了国内外栽培基质材料开发、基质合成、性状研究与改良的现状，及已取得的主要成果和存在的问题，指出了栽培基质今后的发展趋势。     

国内外固体基质研究概况

简介了国内外固体基质发展现状和发展趋势,并结合我国现代农业生产实际情况,综述了固体基质理化参数、栽培容器及营养液的研究与利用概况。     

我国蔬菜无土栽培基质研究与应用进展

本研究从基质原料选材、前处理措施,混合基质配比、养分提供,栽培基质的科学使用等方面重点介绍了我国无土栽培基质的新研究成果和应用方法,阐述了我国蔬菜无土栽培基质的研究与应用概况及发展趋势。     

西欧和北美的无土栽培

西欧、北美的无土栽培以基质栽培为主,NFT面积很小。西欧作物种植比例,蔬菜占80％以上,花卉和其他作物较少。基质栽培中以岩棉发展最快,今后发展的动向,岩棉板栽培仍将占压倒的优势,袋培次之,砂培和NFT也将有一定的发展。温室节能,作物生理及无土栽培设备的改进,仍是今后研究的重点。     

铁皮石斛栽培基质的研究进展

栽培基质是铁皮石斛栽培成功和优质高产的关键因素,通过对国内现有文献的调查研究,从铁皮石斛栽培基质需满足的条件以及铁皮石斛栽培基质的来源、种类、研究现状四方面进行阐述,总结了铁皮石斛栽培基质的研究进展,以期为铁皮石斛栽培基质的深入研究提供参考。     

不同茬口设施番茄栽培的根圈基质中酶活性与养分效应

研究了番茄设施有机基质栽培的正茬、迎茬、连茬根圈生物性状和理化性状的变化, 分析了不同茬口对番茄栽培基质中酶活性、有机质含量和主要养分含量的影响。结果表明, 番茄连茬栽培基质的蛋白酶、磷酸酶、脲酶和过氧化氢酶活性下降, 有机质、全氮、铵态氮、碱解氮、全磷、速效磷、全钾及速效钾等主要养分含量降低, 而正茬栽培对基质酶活性、有机质和主要养分含量的影响较小。基质酶活性与理化性质的相关性分析表明, 番茄有机基质栽培中, 连茬、迎茬和正茬条件下基质的化学性质与生物学性质密切相关, 从而导致了番茄连茬基质微生态环境的改变。所有指标的相关性中, 脲酶与有机质和主要养分含量的相关系数最大, 说明脲酶活性是影响基质有机质含量和主要养分的重要因子。各茬口中, 速效钾、速效磷、全钾和过氧化氢酶活性的可塑性指数均最大, 不同茬口基质各指标的可塑性指数表现为新基质的最大、正茬次之、连茬最小, 说明连茬基质不适宜于番茄生长, 而正茬基质的生物和理化性质与新基质差异不大, 适宜于番茄生长发育。     

日光温室栽培基质有效导热系数预测模型

栽培基质为固流两相组成的多组分材料,其导热系数是日光温室热环境营造过程中重要的热参数之一,在温室地面热量的传输中起着重要的作用。为了预测日光温室生产中栽培基质的有效导热系数,以珍珠岩、蛭石、炉渣、河沙、椰糠、泥炭及腐熟牛粪与花生壳8种常用单一基质为研究对象,首先利用干燥与饱和状态下基质有效导热系数的测试结果,通过复合材料有效特性混合模型的反向计算,确定了8种单一基质的固相导热系数,得到珍珠岩、蛭石、炉渣、河沙、椰糠、泥炭及腐熟牛粪与花生壳的固相导热系数分别为0.058、0.139、0.252、0.817、0.148、0.518、0.262及0.066 W/(m·K);其次,利用复配基质有效导热系数的实测结果,通过复合材料有效特性混合模型的正向与反向计算,明确了组成固相的各组分呈并联关系排列,并确定了复配基质中固相导热系数与基质各组分体积比例的关联;进一步将复配基质在不同饱和度下的有效导热系数实测值与基于6种复合材料导热系数模型理论计算值进行比较。结果表明：并联模型适用于复配基质有效导热系数的理论计算,构建了日光温室栽培基质有效导热系数的预测模型。采用实际生产中常用的4种育苗和栽培基质在不同饱和度下的有效导热系数对所建模型进行检验,模型预测值和实测值的平均相对偏差范围为0.42%～1.76%。基于并联模型构建的有效导热系数预测模型能够较为准确的计算日光温室栽培基质在不同饱和度下的有效导热系数。     

园林废弃物堆肥用作栽培基质的研究进展

制作栽培基质是园林废弃物资源化利用的有效途径之一,在促进园林绿化事业健康发展的同时,还能缓解生态环境问题。基于此,结合近年来的相关研究文献,探讨了利用园林绿化废弃物堆肥用做植物栽培基质的新技术,以及栽培基质在实际农林业生产中的应用,并对未来的应用前景进行了展望,旨在为园林废弃物在城市绿地生态系统中多样化循环利用提供新思路。     

固体肥种类与施肥量对穴盘小白菜生长及产量品质的影响

试验以小白菜品种“矮脚黄”为材料,以72孔黑色聚乙烯塑料穴盘为栽培容器,采用有机复合基质为栽培基质,研究固体肥种类与施肥量对穴盘小白菜生长、产量、品质及经济效益的影响。结果表明,合理的肥料配比对提高小白菜品质有显著作用,可提高小白菜可溶性糖、可溶性蛋白质和Vc含量,而硝酸盐含量明显下降。在有机肥中加入适当的无机复合肥、生物复合肥可满足小白菜生长旺期对肥料需求量大的要求,发挥基质栽培的最大肥效,使小白菜单株鲜重及整体产量达最高水平,获得较好的经济效益。     

The Case for a Two-Step Approach to Agricultural Campaign Design

Development campaigns designed to scale up effective agricultural solutions often rely on media. Information and communication technologies for development (ICT4D) proponents argue that increased media penetration is necessary for such campaigns to succeed. Interviews of 63 extension agents and 200 farmers in Burkina Faso about their disparities in media ownership, access, skills, and preferences suggest that agricultural development campaigns should account for the different media environments and preferences of target populations within countries. This research presents such an alternative approach, a two-step campaign design intended to address digital divides within countries and target population preferences.     

非水相流体在多孔介质中迁移的研究进展

从非水相流体（NAPLs）在多孔介质中的持留特性、渗透特征、迁移的数学模型以及试验方法和技术等方面综述了非水相流体在多孔介质中迁移理论的研究进展。在分析国内外研究现状的基础上，指出了今后非水相流体在多孔介质中迁移理论研究的方向和发展趋势，提出了需要进一步研究的关键性问题。     

Nutrient Leaching When Compost Is Part of Plant Growth Media

Engineered plant growth media must support plant growth while minimizing environmental impact. The objective of this research was to determine how different growth media influence nutrient leaching. Plant growth media contained varied amounts of soil, sand, compost that did or did not contain manure, and possible sorbents for phosphorus. If the plant growth media included compost derived partly from manure, leaching losses of nutrients were excessive due to the high nutrient load in the compost. Layering compost over the plant media mix resulted in lower nitrate concentrations in effluent (87 mg L^?1) compared with mixing compost into the media (343 mg L^?1); however, growth of prairie grasses was reduced because of dense media below the compost blanket (0.09 versus 0.31 g). Using lower amounts of compost that did not contain manure resulted in lower mean nitrate concentrations in effluent (101 versus 468 mg L^?1). Media that had no soil (13.3 mg L^?1) had greater loss of phosphorus after harvest for unsaturated drainage than media with soil (1.8 mg L^?1). To reduce nitrate leaching, only small amounts of low-nutrient compost (higher C:N ratio) should be incorporated into the media. If compost is applied as a surface blanket without incorporation, then soil should be added to the sand to reduce density of the media and increase plant growth.     

动物腔前卵泡的研究进展

综述了各种动物（鼠、兔、羊、牛、猪、猫和犬）腔前卵泡的研究历史和现状，主要讨论了腔前卵泡的分离方法、体外培养技术和培养液的添加成分等问题。     

Experimental study and modelling of the water phase change kinetics in soils

When dealing with porous media, the liquid‐gas phase‐change is generally considered instantaneous, while a retardation time is observed in the case of hygroscopic soils. So far, little research has been done to characterize the non‐equilibrium behaviour of water phase change. Therefore, we propose a macroscopic model of the liquid‐gas phase‐change rate in porous media, based on the difference of chemical potentials between the liquid and its vapour, which is taken as the driving force. It introduces a phenomenological coefficient that must be determined experimentally. An original experiment able to create a macroscopic non‐equilibrium between the liquid and its vapour is described. Analysing the return to equilibrium leads to the determination of the phenomenological phase‐change coefficient. Depending on the range of partial vapour pressure, two different behaviours are observed: a linear domain close to equilibrium and a non‐linear one far from equilibrium. The results emphasize the relation between water retention properties in hygroscopic porous media and these phase‐change characteristics.     

Listeria methods development research at the Eastern Regional Research Center, U.S. Department of Agriculture

Listeria methods research at the U.S. Department of Agriculture, Eastern Regional Research Center, has concentrated on 2 areas during the past year. The first was development of techniques for assessing isolation methods for their ability to detect sublethally stressed cells. It appears that a number of widely used media do not accurately detect Listeria that have been injured by thermal processing or acidification. The second was development of improved plating media. One, modified Vogel-Johnson agar, shows promise; it is highly selective and quantitative, and eliminates the need to select colonies on the basis of a blue color when illuminated with reflected light.     

干旱条件下NK超高吸水性树脂在甘草栽培中的应用

在室内和室外模拟沙漠干旱条件下,研究强化辐射交联技术制备的NK超高吸水性树脂Ⅰ、Ⅱ和Ⅲ作为保水剂用于甘草的栽培。结果表明1.0%左右超高吸水性树脂Ⅲ可保证甘草正常生长所需的水分;播种后种子表面覆沙5~7cm、采用自然浸水方法能促进甘草的出苗及生长发育,有利于其抗旱保水功能的发挥,提高应用效果。     

湖泊水环境承载力研究

以博斯腾湖为实例研究湖泊的水环境承载力,从湖泊水环境承载力的承载媒介(水资源量和水体质量)入手,以湖泊水环境承载力的承载对象(人口、污染物质、人类活动等等)为基础,建立湖泊水环境承载力研究概念模型和量化模型,通过建立湖泊生态需水量模型、湖泊环境需水量模型,结合系统动力学法计算了博斯腾湖的水资源量承载力,结合二维水流——水质模型模拟了湖泊中的污染物质(BOD、TN、矿化度)浓度分布,通过各点浓度分布经过聚合得到整个湖泊不同水位、不同来水频率下的水环境容量、富营养化水平、矿化度水平,而博湖的有机污染加剧、富营养化、矿化度升高正是湖泊水质受损的重要因子,通过这些因子用多目标规划模型得到湖泊的水质承载力。最后,将水资源量承载力和水质承载力结合得到湖泊的水环境承载力,对于湖泊水环境承载力的研究具有重要意义。     

不同成熟液对猪卵母细胞体外成熟和体外受精后早期胚胎发育的影响

本研究探讨了不同成熟液[改良TCM-199液(mTCM)和改良NCSU-23液(mNCSU)]对猪卵母细胞体外成熟和体外受精后早期胚胎发育的影响，以期提高其受精和胚胎发育潜能。试验表明：(1)猪卵母细胞的核成熟与其周围的卵丘细胞扩展没有必然的联系，卵丘细胞扩散或成放射状不宜作为猪卵母细胞核成熟的标准，只有排出第一极体才能作为猪卵母细胞核成熟的标志；(2)利用mTCM 10％猪卵泡液和mNCSU 10％猪卵泡液的猪卵母细胞体外培养核成熟效果优于mNCSU 10％胎牛血清，但这三组成熟液对猪卵母细胞的卵丘细胞扩散和体外受精后的早期胚胎发育无显著影响。     

Utilization of Agricultural Waste Compost as an Alternative Potting Media Component with Coir Dust for Leafy Vegetable Ipomoea Acquatica

The aim of this research was to study the potential utilization of an alternative potting media developed from agricultural waste compost in combination with coir dust on the growth and development of leafy vegetable Ipomoea aquatica (L). Agricultural waste compost was prepared from poultry litter, sawdust, rice straw, gliricidia, and cow dung. Seven different potting media were prepared by mixing compost at the rates of 0%, 10%, 25%, 50%, 75%, and 100% with coir dust at the rate of 100%, 90%, 75%, 50%, 25%, and 0%, respectively. Developed potting media showed adequate physical and chemical properties for Ipomea aquatica cultivation. Crop yield showed significant differences among all treatments and treatment with 100% compost gave the best growth and yield parameters. The highest plant height, shoot fresh weight and shoot dry weight obtained from the 100% compost were increased by 2.70, 18.07, and 18.02 times in comparison to the 100% coir with chemical fertilizer control.