鸡粪改良对铜尾矿基质中无机氮组分及3种豆科植物生长发育的影响

基质改良和耐性物种选择是重金属矿业废弃地生态修复的关键。本文通过室内盆栽试验,以4kg尾矿为植物盆栽基质,分别加入腐熟鸡粪0、8、16、32g混匀,记作MA0（CK）、MA8、MA16、MA32处理方式,研究不同比例腐熟鸡粪改良对铜尾矿基质中无机氮组分及3种豆科植物决明（Cassia tora）、田菁（Sesbania cannabina）、菽麻（Crotalaria juncea）生长发育的影响。结果表明,添加鸡粪改良处理后,3种豆科植物生长的尾矿基质中均以硝态氮为有效氮的主要形态,总无机氮含量为17.96～44.82mg·kg-1。其中菽麻MA32处理组尾矿基质中铵态氮含量（5.31mg·kg-1）最高,菽麻MA16处理组尾矿基质中硝态氮含量（43.06mg·kg-1）和总无机氮含量（44.82mg·kg-1）最高。MA16处理时,田菁和菽麻叶绿素a、叶绿素b、叶绿素a＋b值均表现最大。3种豆科植物叶绿素a/b为0.92～1.08。在同一鸡粪比例处理中,菽麻叶绿素a、叶绿素b、叶绿素a＋b值均显著高于决明和田菁（P〈0.05）。鸡粪改良铜尾矿基质能够促进3种豆科植物生长,植物株高、冠幅、根长均增加,并且随着生长期延长,增加明显。其中MA32处理菽麻70d株高（94.40cm）最大,阻止尾矿风蚀水蚀的效果最好。综合分析表明,MA16处理方式可作为鸡粪改良铜尾矿基质理想的比例模式,菽麻可作为铜尾矿生态修复优选植物种。     

蜡样芽孢杆菌菌株X5强化的生物有机肥能有效控制根结线虫(Meloidogyne sp.)

The efficacy of Bacillus cereus X5 as a potential biological control agent against root-knot nematodes was evaluated in vitro by examining second-stage juvenile mortality and egg hatching rate under addition of culture filtrate and in planta by application of bio-organic fertilizers enhanced with B. cereus X5, B. thuringiensis BTG, or Trichoderma harzianum SQR-T037 alone or together in greenhouse and field experiments. The biofumigation of the root-knot nematode-infested soil with organic materials (chicken manure, pig manure and rice straw) alone or in combination with B. cereus X5 was also conducted in greenhouse experiments. In laboratory, the filtrate of B. cereus X5 more effectively reduced egg hatching rates during the incubation period for 14 d and more effectively killed the second-stage juvenile during the incubation period of 24 h than that of B. thuringiensis BTG. The highest dry shoot weights for greenhouse tomatoes and field muskmelons were found in both the treatment consisting of the bio-organic fertilizer enhanced with the three biocontrol agents and the treatment consisting of the bio-organic fertilizer enhanced only with B. cereus X5. The two bio-organic fertilizers achieved better nematicidal effects than those enhanced only with B. thuringiensis BTG or T. harzianum SQR-T037. B. cereus X5 also enhanced effect of biofumigation, which resulted in increased plant biomass and reduced nematode counts in the roots and rhizosphere soil. Therefore, these results suggested that biological control of root-knot nematodes both in greenhouses and fields could be effectively achieved by using B. cereus X5 and agricultural wastes.     

铝对大豆叶片水势和生理特性的影响

以2个大豆{Glycine max(L.)Merrill}品种华春18,浙春3号为材料,设置不同的铝浓度进行土培试验,研究铝对大豆叶片水势和一些生理特性的影响。结果表明:高浓度的铝对大豆生长明显不利。随铝浓度的增加,大豆叶片水势略有下降;蛋白质含量在三叶期有所上升,然后在五叶期开始下降;叶绿素含量除三叶期外都有明显下降;二个大豆品种的SOD活性变化明显不相同。从种间差异性来看,浙春3号抗铝胁迫的能力大于华春18。     

阴山北部耕作土壤表土颗粒分析模型探讨

在内蒙古自治区阴山北部农牧交错带耕地表土33组颗粒分析实验数据基础上,运用M atlab软件对VanGenuchten等模型进行模拟求参,并得到能较为精确地表征当地土壤颗分曲线的数学模型,以期为全面综合分析阴山北部农牧交错带风蚀沙化地表土壤的抗风蚀能力有所帮助。     

根相对伸长率不能反映大白菜对镉的耐性差异

以14种大白菜为材料,研究根的相对伸长率与蔬菜地上部Cd耐性之间的关系.结果表明,种子根的相对伸长率与大白菜苗期的Cd耐性没有相关性,因而用种子根相对伸长率不能衡量大白菜对Cd的耐性.大白菜地上部Cd含量与Cd耐性指数呈负相关,表明Cd耐性强的大白菜地上部Cd的累积量相对较低.     

长江三角洲地区污泥中多环芳烃的污染研究

To ascertain the contaminated conditions of polycyclic aromatic hydrocarbons （PAHs） in sludge and to evaluate the risk of application of this sludge for agricultural purposes, 44 sludge samples obtained from 15 cities in the Yangtze River Delta area of China were investigated using capillary gas chromatography/mass spectrometry （GC/MS） after ultrasonic extraction and silica gel cleanup. PAHs＇ contents ranged from 0.0167 to 15.4860 mg kg^-1 （dry weight, DW） and averaged 1.376 mg kg^-1, with most samples containing 〈 1.5 mg kg^-1. Pyrene （PY）, fluoranthene （FL）, benzo[b]fluoranthene （BbF）, indeno[1,2,3-cd]pyrene （IND）, benzo[a]pyrene （B[a]P）, and benzo[g,h,i]perylene （BghiP） were the most dominant compounds, ranging from 0.1582 to 0.2518 mg kg^-1. Single PAH, such as naphthalene （NAP, 2-benzene rings）, phenanthrene （PA, 3-benzene rings）, PY （4-benzene rings）, and FL （3-benzene rings）, had high detection rates （76.1%-93.5%）. The distribution patterns of PAHs were found to vary with the sludge samples; however, the patterns showed that a few compounds with 2- and 3-benzene rings were commonly found in the samples, whereas those with 4-, 5-, and 6-benzene rings were usually less commonly found. All the 44 sludge samples were within the B[a]P concentration limit for sludge applied to agricultural land in China （〈 3.0 rag kg^-1）. The probable sources of PAH contamination in the sludge samples were petroleum, petroleum products, and combustion of liquid and solid fuel. The concentrations and distributions of the 16 PAHs in sludge were related to sludge type, source, and treatment technology, together with the physicochemical properties.     

宁夏引黄灌区农田土壤酶活性及其空间变异

采集了同一地点不同土地利用方式,及不同地点不同典型土地利用类型下银川平原的灌淤土样品,在分析了土壤基本理化性质的基础上,用奈氏比色法、苯磷酸二钠比色法和高锰酸钾滴定法,分别测定了宁夏引黄灌区农田不同利用方式下土壤的磷酸酶、脲酶、过氧化氢酶的活性状况,并对土壤酶活性与土壤的基本理化性质的相关性进行了相关分析。结果表明,土地利用方式对三种酶活性有很大的影响。12年果园磷酸酶活性最高,常年旱田脲酶和过氧化氢酶活性最高,而盐化旱田及常年淹水的稻田,三种酶活性都很低。脲酶活性与土壤全氮之间显著正相关,全磷与三种酶活性都极显著相关,三种酶之间达到显著或极显著正相关关系。表明磷酸酶、脲酶和过氧化氢酶活性的大小可以敏感地表征宁夏引黄灌区土壤肥力和生产力的高低。     

青梅酒加工工艺及产品功能性研究进展

综述了青梅酒的加工工艺、产品功能性的研究现状;提出了有待解决的问题和今后研究与发展的方向,展望了青梅酒的发展前景.     

玫瑰黄链霉菌Men-myco-93-63负调控基因nsdAmgh的克隆及序列分析

nsdA (Negative regulator of Streptomyces differentiation)基因是天蓝色链霉菌中发现的与抗生素合成相关的负调控基因.根据天蓝色链霉菌 A3(2)的序列设计引物扩增玫瑰黄链霉菌 Men-myco-93-63 菌株中的该基因,经测序和序列分析表明,由保守序列引物nsdA-2R和nsdA-2L克隆到的Men-myco-93-63 菌株中的该基因 800 bp片段与已知nsdA基因核苷酸保守区域序列同源性达到99%,由全长序列扩增引物nsdA WZ-R和nsdA WZ-L克隆到的该基因包含一个完整的开放阅读框,共编码 369 个氨基酸,与变铅青链霉菌和天蓝色链霉菌A3(2)中的nsdA 基因的核苷酸序列同源性达到100%,氨基酸序列同源性达到99%.该全长基因命名为nsdA_(mgh),其在玫瑰黄链霉菌 Men-myco-93-63 中的发现为阻断该负调控基因以期获得抗生素高产工程菌株提供了重要依据.     

棉麦两熟棉纤维强度与铃期气象因子关系研究

研究棉麦两熟棉纤维强度与铃期气象因子关系的结果表明,相对湿度是影响棉麦两熟多类型、棉株多部位铃棉纤维强度的主要气象因子,相对湿度对纤维强度的作用均为负效应,作用大小因棉铃着生部位而异。日照时数对两熟春棉、温度对两熟短季棉棉株上部（７～９果枝）、顶部（１０以上果枝）铃棉纤维强度有重要作用,均为正效应。