Ammonia-oxidizing communities in agricultural soil incubated with organic waste residues

The impact of organic compounds present in different kinds of organic fertilizers, i.e., anaerobically digested household waste, composted organic household waste, swine manure, and cow manure, on microbial communities in arable soil was investigated using microcosms. Soil was amended with dried residues or organic extracts of the residues and incubated for 12 weeks at 25°C. The microbial community composition was investigated by phospholipid fatty acid (PLFA) analysis, and the community of ammonia-oxidizing bacteria (AOB) was assessed by denaturing gradient gel electrophoresis (DGGE) of 16S rDNA fragments, followed by sequencing. All dried residues increased the AOB activity, determined as potential ammonia oxidation, whereas the organic extracts from the thermophilically digested waste and the swine manure caused a decreased potential activity. However, no differences in the DGGE banding patterns were detected, and the same AOB sequences were present in all samples treated with the residue extracts. Moreover, the PLFA composition showed that none of the residue additions affected the overall microbial community structure in the soil. We conclude that the AOB community composition was not affected by the organic compounds in the fertilizers, although the activity in some cases was.     

Sensitivity Studies of the Common Bean (Vigna unguiculata) and Maize (Zea mays) to Different Soil Types from the Crude Oil Drilling Site at Kutchalli, Nigeria (7 pp)

Background, Aims and Scope   The economic growth that Nigeria has enjoyed as a result of oil revenue has its drawback through exposure of people in the oil producing areas to environmental contamination, due largely to the increase in the movement of oil. Activities associated with oil well drilling on agricultural lands have led to serious economic losses on the communities affected. The local people in most of these communities are peasants who do not know how to react to drilling wastes or polluted fields where they have their crops. A case under study is the Kutchalli oil drilling area. Methods   Waste pit soil from drilling waste dumps in Kutchalli oil drilling area was tested whole and in combinations with 'clean' soil for their abilities to support plant growth and development in common bean (Vigna unguiculata) and maize (Zea mays). Seed germination, plant height, leaf area, biomass accumulation, respiratory activity as well as soil chemical analysis were used to access the ability of waste pit soil to support plant growth and development in the test plants. Results   Discussion and Conclusions. Waste pit soil completely inhibited the germination of bean and maize seeds. Waste pit soil in combinations with different proportions of Kutchalli soil gave growth (germination, height of plants, number of leaves, leaf area, etc.) values that were inferior to the control soil (Kutchalli) and the independent control soil (Monguno). Seeds planted in the test soil combinations containing waste pit soil showed significantly low respiratory activity. Waste pit soil seems to be toxic to plant growth and development. Drilling mud in combination with native Kutchalli soil significantly enhanced plant growth and development. Recommendations and Outlook   The seed germination, growth and development inhibition by waste pit soil suggests its toxicity. We want to suggest the need for strict control and monitoring of waste pit soil in oil drilling sites.     

煤矸石自然风化及人工模拟风化过程中盐分及pH值的动态变化——以平朔露天矿区为例

为揭示煤矸石初期物理崩解风化过程中盐分和pH值的动态变化规律,选择了山西平朔露天矿区17处暴露地表自然风化5年和14年粒径为0.1～10.0mm的风化煤矸石,以及经过人工破碎粒径也为0.1～10.0mm的新鲜煤矸石为对比材料。研究结果表明:自然风化14年左右的煤矸石全盐量高于风化5年左右的煤矸石。自然风化煤矸石pH值的变化幅度为6.55～9.20,人工破碎新鲜煤矸石的pH值为7.26～7.95。人工破碎新鲜煤矸石30min、48h、96h浸水试验结果表明,同一浸泡时间含盐量随着粒径缩小而升高,同一粒径随着浸泡时间的延长而变大;同一浸泡时间pH值随着粒径缩小而降低,同一粒径随着浸泡时间的延长也变大;风化煤矸石的pH值和全盐含量>新鲜煤矸石。     

ABEVIEW AND SOME SUGESTIONS ON THE GENERA SITUATIONS OF DISPOSAL OF MUNICIPAL REFUSE IN OUR COUNTRY

This paepr mainly describes the conditions of disposal of municipal dom-estic refuse in onr country,and compares the methods of disposal of munic-ipal refuse with that of other countries.According to the specific conitionsof the cities in on our country,this paper also presents several suggestionson the collection,transport,disposal and use of municipal refuse.     

Study on the Exterior Wall External Thermal Insulating Mortar Made from Waste Expanded Polystyrene(EPS)

The surface of modified EPS can be changed from the character of water-repellent to hydrophilic,and be wetted by freshly mixed portland cement paste.A new thermal insulating mortar with good properties of workability,thermal insulation,climate-resisting and crack-resisting can be made modified EPS as light aggregate and cement as binder,and modified with fiber and polymer.This new type of insulating mortar can be used as exterior wall thermal insulation,which breaks the limitation of traditional insulating mortar only as interior insulation.It has been widely used in civil engineering.     

Analysis on Influence of Gases Generated by Anaerobic Fermentation of Solid Organic Wastes to Atmosphere in Three Gorges Reservoir Area

The gases generated by anaerobic fermentation of organic solid wastes in Three Gorges Reservoir Area are CH_4,CO_2,H_2S,NH_3,H_2 and some micro-gases.Data analysis shows that in the cities and towns of Three Gorges Reservoir Area,4 380 thousand tones of garbage,3 800 thousand tones of faecal were generated each year.In landfill of the garbage in average of 290 millions kg of CH_4 was generated,also in average of 230 millions kg of CH_4 was generated from the faecal.CH_4 is a very important greenhouse gas;the proportion of its contribution to greenhouse effect is next to CO_2.Other gases only have small influence on the whole atmospheric environment.     

Recent Development of Solid/Liquid Reaction Synthesis Technology for Metal Matrix Composites

TheSolid/liquidReactionSynthesisTechnologyforMetalMatrixCompositeshasattractedanincreasinginterest, andalotofimportantprogresseshavebeenmadeinrecentyears.Fivetypicalprocesses ,exothermicdispersion ,coatingtech nologybycontactreaction ,liquidcontactreaction ,meltinfiltrationandreactivespraydeposition ,havebeenreviewed .More attentionhasbeenpaidtorecentdevelopmentoftheresearchworkontheexothermicdispersion ,coatingtechnologybycontact reactionandliquidcontactreaction .Thecharacteristicsoftheseprocessesareanalysed ,andtheexistedproblemsonthereac tionsynthesistechnologiesarediscussed .     

种养废弃物生物处理技术的应用

种养废弃物生物处理技术是利用蚯蚓养殖处理玉米秸秆和养殖场粪便的技术模式。技术的应用为种养废弃物提供了一条资源化利用之路,可以减少秸秆焚烧现象,提高空气质量,解决养殖粪便污染,实现资源化利用,促进增加农民收入,为农村经济发展提供一条致富新途径,具有较好的经济效益和社会生态效益,对促进天津市“美丽乡村”建设具有重要意义。基于此本文深入分析了试验结果,详细阐述了该技术的创新点,以及对社会及环境生态效益。     

枯草芽孢杆菌、酿酒酵母及其复合菌发酵棉粕营养成分变化的研究

试验旨在研究枯草芽孢杆菌、酿酒酵母及其复合菌发酵棉粕的常规营养成分、棉籽肽含量及棉籽肽分子质量分布的变化。试验设4个组：对照组（未发酵组）、试验Ⅰ组（枯草芽孢杆菌-1）、试验Ⅱ组（酿酒酵母）及试验Ⅲ组（枯草芽孢杆菌-1和酿酒酵母复合发酵）。检测各组棉粕样品粗蛋白质（CP）、干物质（DM）、粗灰分（Ash）、中性洗涤纤维（NDF）、酸性洗涤纤维（ADF）、粗脂肪（EE）、钙（Ca）、磷（P）、棉籽肽含量和棉籽肽分子质量分布等指标。结果表明：①试验Ⅰ组DM、CP和Ash含量极显著高于其他处理组 （P < 0.01）;对照组EE含量显著高于其他处理组 （P < 0.01）;试验Ⅲ组ADF含量极显著低于其他处理组（P < 0.01）;3个试验组Ca和P含量较对照组均有所提高,其中试验Ⅲ组Ca和P含量显著高于对照组（P < 0.05）。②各试验组之间游离氨基酸和总游离氨基酸含量差异均不显著（P > 0.05）,但与对照组相比,试验Ⅰ、Ⅱ、Ⅲ组总游离氨基酸含量分别提高了134.02%、75.59%和75.44%;③各试验组酸溶蛋白质和棉籽肽含量均极显著高于对照组（P < 0.01）,其中试验Ⅰ组的酸溶蛋白质和棉籽肽含量最高;3个发酵试验组1 000 u以下的棉籽肽峰面积百分比分别为89.41%、77.61%和84.58%。综合以上试验结果,在枯草芽孢杆菌、酿酒酵母及其复合菌的作用下,通过固态发酵能显著改善棉粕的营养价值,为棉粕资源的开发利用提供了理论依据。     

扇贝加工废弃物自溶技术的研究

对扇贝加工废弃物的自溶水解技术进行了研究。结果表明:用紫外线照射扇贝加工废弃物后能够激活自溶酶,当照射40 m in时,自溶水解液中游离氨基酸态氮含量最高(3.389 g/L);pH对自溶水解影响较大,pH为7.0时水解效果最佳;采用40-65℃(5℃/h)的梯度升温自溶水解4 h或60℃恒温下自溶水解3 h,其水解效果最佳;无机离子Na 、Ca2 对自溶酶具有激活作用,当Na 的浓度为0.07 mol/L、Ca2 的浓度为0.03 mol/L时,自溶水解效果最佳,而Zn2 对自溶酶的影响很小;扇贝加工废弃物在最佳条件下自溶水解3 h后(60℃恒温),其水解液中氨基酸态氮的含量为4.006 g/L。用SephadexG-15葡聚糖凝胶柱层析法对扇贝加工废弃物的自溶水解产物进行分析,结果显示,水解液中蛋白肽相对分子质量集中分布在784.25左右,说明自溶水解产物多为小分子的蛋白肽,可进一步对其开发利用,制备海鲜调味料等。