共查询到18条相似文献,搜索用时 171 毫秒
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外来植物入侵对土壤生物多样性的影响已成为生态学领域的研究热点之一。运用Biolog技术和氯仿熏蒸浸提法研究了黄顶菊入侵对土壤微生物群落功能多样性及土壤微生物量的影响。结果表明,黄顶菊入侵后土壤微生物代谢活性显著升高;土壤微生物群落平均吸光值(4WCD)的变化趋势为:入侵地根际土(RPs)〉入侵地根围土(Bs)〉未入侵地(CK),且差异显著;而CK的功能多样性指数(日)高于BS,RPS亦高于Bs,差异均显著(P〈O.05)。主成分分析结果表明,黄顶菊入侵使土壤微生物群落的碳源利用方式和代谢功能发生改变。对不同碳源利用的分析结果表明,糖类、氨基酸类、羧酸类和聚合物为土壤微生物利用的主要碳源。入侵样地Bs和RPS的微生物量碳分别比CK高27.05%、121.52%;BS和RPS的微生物量氮分别比CK高37.40%、79.80%。相关性分析表明,AWCD与微生物量碳和微生物量氮均呈极显著正相关(P〈0.01)。由此可知,黄顶菊入侵增强了入侵地土壤微生物代谢活性,降低了土壤微生物群落的功能多样性,增加了土壤微生物量碳、氮水平。 相似文献
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植物及微生物联合修复石油-重金属复合污染土壤具有很大的潜力。但重金属以不同形态存在关系到石油-重金属复合污染土壤生物修复过程中,植物、微生物的修复效率以及是否需要增加辅助工程解决重金属污染等问题,因此石油-重金属复合污染土壤修复过程中就必须考虑重金属有效态及形态的变化特征。 相似文献
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氮素和水分对贝加尔针茅草原土壤酶活性和微生物量碳氮的影响 总被引:1,自引:0,他引:1
在内蒙古贝加尔针茅草原,分别设对照(N0)、1.5 g·m^-2(N15)、3.0 g·m^-2(N30)、5.0 g·m^-2(N50)、10.0 g·m^-2(N100)、15.0 g·m^-2(N150)、20.0 g·m^-2(N200)和30 g·m^-2(N300)(不包括大气沉降的氮量)8个氮素(NH4NO3)梯度和模拟夏季增加降水100 mm的水分添加交互试验,研究氮素和水分添加对草原土壤养分、酶活性及微生物量碳氮的影响。结果表明:氮素和水分添加对草原土壤理化性质和生物学特性有显著影响。随施氮量的增加土壤总有机碳、全氮、硝态氮、铵态氮含量呈增加的趋势,相反,土壤pH值呈降低的趋势。土壤脲酶和过氧化氢酶的活性随施氮量的增加而升高,多酚氧化酶则随施氮量的增加呈下降的趋势。氮素和水分添加对草原土壤微生物量碳氮含量有显著影响,高氮处理(N150、N200和N300)显著降低了微生物碳含量,微生物氮含量随施氮量的增加呈上升趋势。水分添加能够减缓氮素添加对微生物的抑制作用,提高微生物量碳、微生物量氮含量。草原土壤养分、土壤酶活性及土壤微生物量碳氮含量间关系密切,过氧化氢酶与全氮、总有机碳、硝态氮呈显著正相关,多酚氧化酶与铵态氮、硝态氮、全氮呈显著负相关。微生物量氮含量与土壤全氮、铵态氮、硝态氮含量以及过氧化氢酶和磷酸酶活性呈显著正相关,与多酚氧化酶呈负相关;微生物量碳与过氧化氢酶呈负相关,与多酚氧化酶活性呈正相关。 相似文献
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对武汉市某小型浅水人工湖泊水质进行一年的理化监测并分析,结果显示:COD、BOD5均有季节性变化的规律;气温的变化影响湖水及底泥中微生物的活性;天然降水量不同对湖水稀释程度不同;底泥的污染物释放量受温度影响;该水体可生化性差。据此,提出保护湖水的措施。 相似文献
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微生物强化修复盐渍化石油污染土壤研究* 总被引:2,自引:0,他引:2
采集东营地区石油污染土壤,进行微生物修复实验研究。考察投加复合菌株CM-13是否能够加速生物修复进程以及土壤中石油污染物质降解的影响因素。石油污染土壤经过90 d的处理,在含水量一定的前提下,复合菌株CM-13对于石油污染物质的加速降解作用显著,当复合菌株CM-13接种量为土壤质量的10%时修复效果较好。微生物的生长与营养盐的量存在最佳匹配值,土壤中氮的最佳含量为0.20%,磷的最佳含量为0.05%。实验中随着麦糠投加量的增大,石油类的降解率逐渐增大,当麦糠量为土壤体积分数的25%时,对土壤的修复效果最好。 相似文献
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This paper communicates the effect of bioremediation on the performance of Okro plant (Abelmoshus esculentus) in a typical Niger Delta soil that has received 5% crude oil pollution level. Biodegrading bacteria such as Pseudomonas
fluorescen, Acinetobacteria iwofii, Bacillus
subtilus, Arthrobacter
globiformis that was isolated from previously polluted soils was introduced into the samples. The treatment combinations are as follows
(A) = control without crude oil; B = soil + crude oil, (C) = soil + crude oil + microbes, (D) = soil + crude oil + microbes,
(E) = soil + crude oil + microbes + fertilizer (F) soil + microbes and (G) = soil + fertilizer. The treatment (E) gave the
highest number of leaves, % crop emergence, plant biomass, microbial population and degradation of petroleum hydrocarbon compared
to any of the treatments that had received crude oil. This suggested that fertilizer application does not only stimulate microbial
growth but it provides the plant with more available nutrients required for plant growth. 相似文献
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石油污染土壤原位生物修复的强化实验研究 总被引:2,自引:0,他引:2
为研究添加营养物质和高效降解石油微生物对油污土壤生物修复的作用,通过分层土柱的方法,连续监测了不同条件下不同土层的含水率、石油烃含量、细菌数量及脱氢酶活性。结果表明:添加营养物质同时接种高效微生物可使降解效果明显改善,降解率比在自然条件下提高近50%,而单纯添加营养物质不接种高效微生物可使降解率比在自然条件下提高约25%。降解初期,上层土壤降解效果较好,而到中后期,中下层降解效果好于上层。微生物数量和脱氢酶活性与石油降解率之间存在良好的相关性,脱氢酶活性比微生物数量更能反映修复过程中微生物的存活状态。添加营养物质和高效降解石油微生物对油污土壤原位生物修复具有强化作用。 相似文献
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为探讨原油伴生卤水对农作物的影响,进行了种子发芽率试验和田间试验,确定了土壤氯化物含量影响棉花生长的临界值。结果表明,当土壤中氯离子含量大于306.7 mg/kg时,可明显影响棉花的正常生长,使产量明显下降,并污染土壤环境。 相似文献
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热碱水溶液清洗-气浮分离对原油污染土壤的处理 总被引:8,自引:1,他引:8
针对落地原油的回收及土壤污染治理问题,提出了用热碱水溶液清洗-气浮分离的处理方法,获得了比较理想的结果。实验中考察了清洗过程的反应温度、清洗时间、液固比、碱浓度及气浮温度和气浮时间等各种影响因素,得到了适宜的处理工艺条件。在此处理条件下,可使含稠油12.5%的模拟含油土壤的油去除率达到92.5%~93.5%,土壤中残留含量降至0.9%~1.0%.提出的处理方法,能原消耗较低,碱剂费用仅为7元/t(t土)左右,且可以回收洗脱出来的原油。 相似文献
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Effect of the Prestige oil spill on salt marsh soils on the coast of Galicia (northwestern Spain) 总被引:1,自引:0,他引:1
At four estuarine sites on the coast of Galicia (northwestern Spain), all of which were affected by the Prestige oil spill, soil samples were taken from polluted and unpolluted areas and their petroleum hydrocarbon contents, heavy metal contents, and other chemical and physical characteristics were measured. Oil pollution altered both chemical and physical soil properties, aggregating soil particles in plaques, lowering porosity, and increasing resistance to penetration and hydrophobicity. The chromium, nickel, copper, iron, lead, and vanadium contents of polluted soils were between 2 and 2500 times higher than those of their unpolluted counterparts and the background concentrations in Galician coastal sediments. In the cases of Cr, Cu, Ni, Pb, and V, their origin in the polluting oil was corroborated by the high correlation (r >/= 0.74) between the concentrations of these metals and the total petroleum hydrocarbon (TPH) content of the polluted soils. Soil redox potentials ranged from -19 to -114 mV in polluted soils and 112 to 164 mV in unpolluted soils, and were negatively correlated with TPH content (p < 0.01). The low values in the polluted soils explain why the soluble fractions of their total heavy metal contents were very small (generally less than 3%, and in many cases undetectable). 相似文献
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固定化微生物修复石油污染土壤特性试验 总被引:2,自引:0,他引:2
利用梯度稀释法分离筛选原油降解混合菌,采用吸附法将混合菌固定在砾石和草炭土上,探讨固定化混合菌对土壤石油烃的去除效果。结果表明:分离得到的混合菌8-2,菌群结构简单,石油烃降解率可达52.1%。与砾石相比,草炭土所固定的微生物数量和活性较高,可达1.3×108 cfu/g和0.24A487。草炭土固定的混合菌8-2,修复含油量为30g/kg的污染土壤30d后,石油烃降解率达28.4%,高于游离降解菌的24.3%。固定化载体草炭土在修复过程中起到了微生物缓释剂的作用。 相似文献
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The potential of periwinkle shell (PS) in enhancing the microbial break down of crude oil spilled in soil were studied. The results revealed that the counts of crude oil degrading bacteria in oil-polluted soil fortified with PS were higher than the counts in unfortified soil. The rates and total extent of crude oil biodegradation in the soil were stimulated by the amendment. About 43.4 percent of crude oil was degraded in unfortified soil after 16 days as compared to 70.1 percent oil biodegradation, which occurred in PS fortified soil during the same period. These values were significantly (P>0.05) different from each other. Amendment of the soil with PS also raised the pH of the soil from acidic to alkaline range. The crude oil degrading microorganisms identified in PS amended soil were of the genus Pseudomonas, Bacillus, Micrococcus, Acinetobacter, Penicillium, Aspergillus, Mucor and Rhizopus. Similarly, Pseudomonas, Bacillus, Micrococcus, Mucor, Aspergillus and Penicillium were identified as crude oil degrading microorganisms in unamended soil. The bacteria formed either stable or unstable emulsions, suggesting that the organisms produce surface-active agents (biosurfactants) during the biodegradation process. The results of this study indicate that PS can be used in reclaiming oil-polluted soil. 相似文献
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本文探讨了3种常用表面活性剂,十二烷基苯磺酸钠(SDBS)、十二烷基硫酸钠(SDS)、聚山梨脂(Tween-80)对被重金属铬、镉污染了的土壤的修复洗脱作用,以及被污染土壤对3种表面活性剂的吸附作用。淋洗实验结果表明,3种表面活性剂对土壤中的铬、镉有明显去除效果,聚山梨脂(Tween-80)对污染土壤中铬和镉的去除率分别为61.2%和37.06%。实验表明,土壤对3种表面活性剂均有较强的吸附作用,这种吸附作用对土壤重金属的去除会产生不利的影响。 相似文献