不同海拔高寒草甸土壤微量元素含量及其与植被的关系

为了探究高寒草甸微量元素随海拔的分布特征及其与植被的关系。本研究以东祁连山高寒草甸为研究对象,调查并测定了不同海拔下高寒草甸植被群落和土壤微量元素含量,采用冗余分析(Redundancy analysis,RDA)分析土壤微量元素与植被群落的关系。结果表明,高寒草甸植被总盖度、草层盖度、地上生物量、莎草科、豆科和杂类草地上生物量均随海拔的升高呈先升高后降低的趋势,在3 200 m处达最大值,禾本科地上生物量随海拔升高依次降低;土壤钙(Ca)、铁(Fe)、铜(Cu)和锰(Mn)含量随海拔的升高呈先降低后升高的趋势,土壤镁(Mg)、锌(Zn)和钼(Mo)含量随海拔的升高呈先升高后降低的趋势,土壤钴(Co)含量随海拔的升高依次降低,土壤硒(Se)含量随海拔的升高呈波动性上升;相关性分析和RDA分析表明,土壤微量元素Mo和Fe含量显著影响着高寒草甸植被的生长。综上所述,海拔显著影响着高寒草甸土壤微量元素的分布,高寒草甸土壤管理过程中应该关注微量元素Mo和Fe,建议将微量元素Mo和Fe作为高寒草甸土壤健康评价指标。     

茶叶浸泡液中微量元素形态的VisualMINTEQ软件模拟分析

利用火焰原子吸收光谱法测定茶叶浸泡液中常见的4种微量元素的含量,应用离子色谱法检测其中的F^-、Cl^-、NO₂^-、Br^-、NO₃^-、PO₄^3-、SO₄^2-含量,结合Visual MINTEQ软件模拟茶叶浸泡液中Fe、Cu、Zn、Pb 4种微量元素的存在形态,表明Fe、Cu、Zn、Pb分别以Fe(OH)₂⁺、Cu²⁺、Zn²⁺、Pb²⁺为优势态存在于茶叶浸泡液中。     

基质配方对酸柚苗生物量及矿质元素含量的影响

为了筛选低成本的海南酸柚容器苗的基质配方,将海南的农业资源椰糠、甘蔗灰和菜籽饼与澄迈县当地表土按不同体积比配制9种基质,对酸柚苗进行容器育苗,研究不同基质配方对酸柚苗生物量指标(包括地上和地下部干鲜质量、根冠比)及矿质元素含量(包括地上及地下部的全氮、全磷、全钾、全钙及全镁含量)的影响。结果表明:不同基质配方对酸柚苗生物量指标的影响达极显著水平,其中T2(椰糠、表土和菜籽饼体积比4∶1∶1)、T5(椰糠、表土和菜籽饼体积比1∶1∶1)和T9(表土、甘蔗灰和菜籽饼体积比4∶1∶1)处理所育酸柚苗在生物量及矿质元素含量方面均表现良好,适合作为酸柚容器苗的栽培基质配方。     

有机肥料氮替代部分无机氮对水稻产量的影响及替代率研究

通过田间试验,研究了不同氮用量下有机肥料氮替代部分无机氮对水稻产量、氮肥利用率和土壤矿质态氮的影响,试图探索出有机肥料氮替代无机氮的最适替代率,并对有机肥与化肥配施的经济效益进行评价。结果表明:1）有机肥与化肥配施处理（8381~9810 kg/hm2）能获得与单施化肥处理（8381~10124 kg/hm2）更高或持平的产量;2）与单施化肥相比,氮用量在N 240 kg/hm2内,有机肥料氮替代无机肥料氮的最适替代率为10%~20%（相当于施用1500~3000 kg/hm2商品有机肥）,此时水稻产量、氮肥利用率和经济效益都达到最佳水平;3）与单施化肥相比,氮用量在N 240 kg/hm2以内并且有机肥料氮占氮总量的10%~20%时可以获得较为平稳的氮素供应过程,改善了土壤供氮能力。上述结果可为研制有机无机复合肥提供理论基础。     

肉牛血液中矿物质元素的含量与变化研究

用原子吸收光谱法对肉牛血液中的Cu,Zn,Fe和用火焰法对Mg,K进行测定.其结果是Cu,Zn,Fe,Mg,K分别为0.402±0.18μg/mL,2.530±0.75μg/mL,412.562±67.52μg/mL,26.580±3.04μg/mL,371.422±172.704μg/mL.Cu,Zn的含量偏低;Fe,Mg,K的含量符合要求.并研究了不同的海拔高度、性别、饲养水平及妊娠与否等条件下肉牛血液中矿物质元素的变化,其结果为不同海拔高度、年龄、性别、饲养水平和妊娠与否的肉牛血液全血中的Cu,Zn,Fe,Mg,K 5种元素的含量差异不显著,不同年龄组中Zn的含量差异显著,其他元素差异不显著.     

五味子果实不同成熟期微量元素的测定

为了研究五味子果实在不同成熟时期微量元素积累规律,利用原子吸收分光光度法对五味子果实不同发育时期Ni、Co、Cr、Zn、Na、Ca、Mn、Fe 8种微量元素进行测定。结果表明:Ca、Na含量最高,Mn、Fe、Zn含量次之,Ni、Co、Cr含量最少;各个微量元素含量均呈现一定变化规律,大部分元素含量在9月5日即果实成熟期以后趋于稳定。     

不同基因型小麦的Pb积累特性及Pb对矿质元素积累的影响

利用Hoagland’s营养液培养的方法,探讨了百农1306、百农1309、百农160、百农418、温麦6号、周麦18、周麦22和周麦26等8个不同基因型小麦品种(系)的Pb积累特性,以筛选出籽粒Pb低积累型小麦品种(系),并研究了Pb对小麦Ca、Mg、Fe和K等矿质元素积累的影响,为解决重金属积累和矿质营养利用之间的矛盾奠定基础。结果表明,小麦籽粒Pb含量存在基因型差异,百农418籽粒Pb含量最低,温麦6号Pb含量最高。根据同一品种(系)的最高Pb含量部位,将8个小麦品种(系)分为籽粒型、颖壳型、叶片型,对应品种(系)分别为温麦6号,百农1306、百农1309、周麦22,百农160、百农418、周麦18、周麦26。与不加Pb(NO_3)_2的对照相比,Pb(NO_3)_2处理后,8个小麦品种(系)不同部位的Ca、K、Mg、Fe含量变化不同。除周麦22茎秆中Ca含量显著增加外,其他7个品种(系)均降低;8个品种(系)茎秆(周麦22、26除外)、叶片和颖壳中K含量均呈降低趋势;温麦6号和周麦18籽粒中Mg含量显著增加,其他6个品种(系)均显著降低;8个品种(系)叶片中Fe含量均升高。百农418和周麦26的Ca、百农1306和百农418的K、周麦18和周麦26的Mg含量(籽粒除外)变化模式相同。     

Wirkung einer langjährig differenzierten mineralisch-organischen Düngung auf Ertrag,Humusgehalt, N-Bilanz und Nährstoffgehalte des Bodens

Abstract

Since 1966, the effects of increasing mineral N fertilization in combination with different organic fertilizers (without, farmyard manure, straw) were examined at two sites in Saxonia (Methau: loam, Spröda: loamy sand) in two-factorial static experiments with regard to yield, humus content, N-balance, N_min content and DL-soluble contents of phosphor and potassium. During the period 1966–2010, rising N application caused a significant yield increase. Farmyard manure treatments always showed the highest yields. Particularly, the yields of potatoes and sugar beets were considerably increased by applying manure, while this had substantially smaller effects on winter wheat and summer barley. The humus contents decreased clearly on both sites. They were almost halved with omitted organic fertilization. With manure supply, the starting contents could not be kept upright, but they were, in relation to omitted organic fertilization, on a clearly higher level. The effect on humus content, resulting from the straw fertilization, was comparatively weak. Under these experimental conditions, high yields with slightly negative to slightly positive N-balance results, were realised. Before winter, the N_min content increased with rising N supply and showed a significant dependence to the N-balances. In case of manure fertilization, they always were on a higher level. The long-term differentiated fertilization strongly affected the DL-soluble contents of phosphor and potassium of the soil.     

Difference of Low Temperature and Low Irradiance-Resistance between Figleaf Gourd and Cucumber Seedlings Related to Mineral Elements Uptake

We have reported that the roots of figleaf gourd（Cucurbita ficifolia,as rootstock） could improve the resistance of cucumber seedlings（Cucumis sativus L.cv.Jinyan 4,as scion） to 6 h stress at low temperature and low irradiance [1].In this experiment,the relationship between the mineral elements uptake and photosynthetic activity of photosystems in figleaf gourd and cucumber seedlings were to be studied during lowtemperature（8 C） stress under lowirradiance（100 μmol m-2 s-1 PFD） for 5 days.Compared with control seedlings,the maximal photochemical efficiency of PS2（Fv/Fm） and the oxidizable P700（P700＋） of both figleaf gourd and cucumber seedlings decreased,and both Fv/Fm and P700＋ were lower in cucumber leaves than in figleaf gourd seedlings at the end of the stress.Superoxide dismutase（SOD） activity was higher in both leaves and roots of figleaf gourd than in leaves and roots of cucumber at both room temperature and low temperature.However,the product rate of O 2 was lower in figleaf gourd leaves than in cucumber leaves.Upon exposure to the stress,the malondialdehyde（MDA） content increased markedly in leaves and roots of figleaf gourd and cucumber seedlings,and it grewfaster in cucumber seedlings than that in figleaf gourd seedlings.Under adaptive conditions,some mineral elements（Such as Cu,Zn,Mn and Mg） have different contents in leaves and roots between figleaf gourd seedlings and cucumber seedlings.However,at the end of the stress these elements were accumulated apparently in both leaves and roots of figleaf gourd accompanied by no obvious change in cucumber seedlings.     

不同硼效率棉花品种木质部和韧皮部汁液中矿质养分的差异

溶液培养条件下研究硼对2个硼效率不同的棉花品种木质部、韧皮部中硼及其它矿质养分运输的影响。结果表明,缺硼使2个棉花品种木质部汁液硼含量及溢出量明显降低,低效品种降低幅度大于高效品种。供硼充足(0.5mg/L)时,2个棉花品种木质部汁液中硼浓度均小于培养液中硼浓度;缺硼(0.002mg/L)时,高效品种与低效品种木质部汁液硼浓度分别是培养液硼浓度的32.0和20.5倍。缺硼使2个棉花品种木质部汁液中钾、锰、铜、锌含量均升高,高效品种升高幅度较大;钙含量均降低,低效品种降低幅度较大;高效品种镁含量增高,低效品种降低。而2个棉花品种木质部各养分(钾、镁、钙、锰、铜、锌)溢出量均降低,低效品种降低更明显。无论在缺硼或供硼充足时,2个棉花品种韧皮部中硼浓度均极低,但韧皮部溢泌液中其它养分受缺硼影响品种间表现不同,高效品种韧皮部钾、镁、锰、铜溢出量升高,低效品种则降低;2个品种钙、锌溢出量均降低,低效品种降低幅度更大。