Microbial Soil Characteristics Research Articles

The occurrence of clubroot in cruciferous crops correlates with the chemical and microbial characteristics of soils.

Clubroot disease, caused by Plasmodiophora brassicae, is a serious soil-borne disease in Brassica crops worldwide. It seriously occurs in conducive soils of southern China, while never happens in some areas of northern China with suppressive soils. To understanding the differences, we measured the soil suppressiveness, chemical properties, and microbial communities in suppressive and conducive soils by bioassay and sequencing of 16S and 18S rRNA amplicons. The biological basis of clubroot suppressiveness was supported by the ability to remove it by pasteurization. The pH value and calcium content in the suppressive soils were higher than those in the conducive soils. Suppressive soils were associated with higher fungal diversity and bacterial abundance. The fungal phyla Chytridiomycota, Olpidiomycota, and Mucoromycota and the bacterial phyla Acidobacteriota and Gemmatimonadota were enriched in suppressive soils. More abundant beneficial microbes, including Chaetomium and Lysobacter, were found in the suppressive soils than in the conducive soils. Molecular ecological network analysis revealed that the fungal network of suppressive soils was more complex than that of conducive soils. Our results indicate that plant health is closely related to soil physicochemical and biological properties. This study is of great significance for developing strategies for clubtroot disease prevention and control.

The responses of soil microbial characteristics to nitrogen addition and biochar amendment in a Larix kaempferi plantation

Nitrogen (N) deposition is an important environmental factor that can change soil chemical properties. It can also alter the characteristics of microbial communities. The incorporation of biochar into soils is considered a potential strategy to enhance carbon (C) storage in soil and modify the impacts of N deposition. However, the impacts of biochar on the microbial characteristics of soil after short-term N deposition in subtropical plantations remain poorly understood. Here, we investigated the effects of biochar application (0, 5, 10 t ha−1) on soil chemical traits and microbial characteristics (extracellular enzyme activities, microbial community and microbial biomass) in a Larix kaempferi plantation in Shennongjia, China, under N addition (0, 50, 100 kg N ha−1 yr−1) during two growing seasons. We found that simulated N deposition significant increased soil total nitrogen (TN), nitrate nitrogen (NO3−-N) and total phosphorus (TP) concentrations, while heavy N deposition (100 kg N ha−1 yr−1) significant decreased soil microbial biomass nitrogen (MBN) concentration and β-glucosidase (β-GC) activity. Biochar amendment significantly increased soil microbial biomass, TN and soil organic carbon (SOC) concentrations. Both N addition and biochar amendment significantly altered Ascomycota and Basidiomycota relative abundance, with biochar amendment increasing Ascomycota relative abundance and decreasing Mortierellomycota relative abundance under heavy N deposition. Fungal diversity showed a positive correlation to TN, TP and NO3−-N concentrations, but a negative correlation to MBN. Biochar addition inhibited the increase in soil NO3−-N concentration caused by high N addition in the plantation, and influenced the change in the composition of microbial community caused by N addition. Our piecewise structural equation model suggested that N addition affected MBN and fungal diversity directly or indirectly via its effects on soil enzyme activities and properties. In contrast, there were no significant direct or indirect effects on bacterial diversity among all factors. These results improve our understanding of the influence and mechanisms of N addition and biochar amendment on soil microbial characteristics in subtropical coniferous plantations in the short term, and can provide a valuable reference for predicting the future effects of N deposition on soils in this region’s plantation.

油田区多环芳烃污染盐碱土壤活性微生物群落结构解析

PDF HTML阅读 XML下载 导出引用 引用提醒 油田区多环芳烃污染盐碱土壤活性微生物群落结构解析 DOI: 10.5846/stxb201504230835 作者: 作者单位: 长治学院生物科学与技术系,辽宁大学环境学院 沈阳,长治学院生物科学与技术系,长治学院生物科学与技术系,中国科学院生态环境研究中心,中国矿业大学北京化学与环境工程学院 作者简介: 通讯作者: 中图分类号: 基金项目: 国家“863”计划课题（2013AA06A205）；国家科技重大专项课题（2014ZX07204-005）；中国科学院环境生物技术重点实验室开放基金课题（EBT2013A001） Analysis of the structure and distribution characteristics of the microbial community in saline-alkali soil contaminated with polycyclic aromatic hydrocarbons Author: Affiliation: Department of Biological Sciences and Technology,Changzhi University,Changzhi,School of Environmental Science,Liaoning University,Department of Biological Sciences and Technology,Changzhi University,Changzhi,Department of Biological Sciences and Technology,Changzhi University,Changzhi,Research Center for Eco-Environmental Sciences,Chinese Academy of Sciences,Beijing,School of Chemical and Environmental Engineering,China University of Mining and Technology-Beijing,Beijing Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:多环芳烃（Polycyclic aromatic hydrocarbons，PAHs）是土壤中广泛存在的、美国环保总署（USEPA）优先控制的一类有毒（致癌、致突变）的持久性污染物，主要来源于人类活动。土壤微生物多样性是表征土壤质量变化的敏感指标之一。磷脂脂肪酸（PLFAs）分析方法是基于活性微生物细胞膜的PLFAs组分的生化检测技术，克服了传统培养方法只能分离出少量微生物（<1%）的缺点。采用PLFAs方法，解析了土壤活性微生物对PAHs污染胁迫的反应。结果表明，土壤微生物分布情况可分为4种类型：Ⅰ型，微生物PLFAs种类最多，占该区土壤微生物PLFAs种类总数的57.7%，PAHs对变量的解释量最小；Ⅱ型，微生物PLFAs占PLFAs总数的30.8%，PAHs对变量的解释量较小；Ⅲ型，微生物PLFAs种类占总数的7.68%，PAHs对变量的解释量较大；Ⅳ型，微生物PLFAs的种类仅占总数的3.85%，PAHs对变量的解释量最大。相关性分析表明：土壤微生物PLFAs的种类、生物量和生态多样性指数与土壤中萘（Nap）、芴（Flu）、蒽（Ant）、苯并[K]荧蒽（Bkf）、苯并[a]芘（Bap）、茚并[1，2，3-cd]芘（Ind）的相对含量呈负相关关系；与苊（Ace）、菲（Phe）、荧蒽（Fla）、芘（Pyr）、苯并[a]蒽（Baa）的相对含量呈正相关关系；与PAHs的种类和浓度呈负相关关系。结果将为开展PAHs污染土壤的生态风险评价和微生物生物修复技术研究提供理论依据。 Abstract:Polycyclic aromatic hydrocarbons (PAHs) are persistent organic pollutants included in the U.S. Environmental Protection Agency list of priority pollutants because of their toxic, mutagenic, and carcinogenic properties. PAHs have become increasingly prevalent in the soil environment as a consequence of anthropogenic activities. The microbial characteristics of soils are increasingly being considered as sensitive indicators of soil health because of the interrelationship among microbial diversity, soil quality, and ecosystem sustainability. The development of effective methods for studying the diversity, distribution, and behavior of microorganisms in soil habitats is essential for a broader understanding of soil health. Traditionally, the analysis of soil microbial communities has relied on culturing techniques that use a variety of culture media to maximize the recovery of diverse microbial populations. However, only a small fraction (<10%) of the soil microbial community has been accessible using this approach. To overcome these problems, other methods, such as the analysis of phospholipid fatty acids (PLFAs), have been utilized in an attempt to access a greater proportion of the soil microbial community. PLFAs are potentially useful signature molecules because of their presence in all living cells. In microorganisms, PLFAs are found exclusively in cell membranes. This finding is important because cell membranes are rapidly degraded and the component PLFAs are rapidly metabolized following cell death. Consequently, PLFAs can serve as important indicators of active, as opposed to non-living, microbe. Microbial species and biomass in saline-alkali soil contaminated with PAHs were investigated by PLFA analysis, in order to explore the effect of PAHs on the microbial community in saline-alkali soil contaminated with PAHs. The results showed that the distribution of PLFAs in soil can be divided into 4 types (I, II, III, and IV). In Type Ⅰ, the number of microbial PLFAs types in sample soils accounts for up to 57.7% of the total number of microbial PLFAs types, and PAHs in this case are least able to explain the changes of microbial community. In Type Ⅱ, the number of microbial PLFAs types in sample soils is up to 30.8%, and PAHs again provide little explanation regarding the changes of microbial community. In Type Ⅲ, the number of microbial PLFAs types in sample soils comprises up to 7.68%, and PAHs have an increasing effect on the changes of microbial community. In Type Ⅳ, the number of microbial PLFAs types in sample soils comprises only 3.85%, and PAHs have a marked influence on the changes of microbial community. Correlation analysis (Spearman) indicated that the types number, concentration, and diversity index of PLFAs are negatively correlated with the relative content of naphthalene, fluorene, anthracene, benzo[k]fluoranthene, benzo[a]pyrene, and indeno[1,2,3-cd]pyrene, and are positively correlated with acenaphthene, phenanthrene, fluoranthene, pyrene, and benzo[a]anthracene. These results provide a scientific foundation for ecological risk assessment and bioremediation technology of saline-alkali soil contaminated with PAHs. 参考文献 相似文献 引证文献

Labile factions of soil organic matter and microbial characteristics of soil under organic and conventional crop management systems

The aim of this study was to compare contents of labile fraction of soil organic matter and microbial parameters in soil under winter wheat and spring wheat grown according to organic, without animal manure application, and conventional crop management systems. Particulate organic matter fraction in the organically managed soil was significantly higher by 26% than that in the soil under the conventional farming system. Culturable colony forming units of bacteria and fungi, dehydrogenase and alkaline phosphatase activities, as well as C contents in microbial biomass and in hot water extracts (HWE) were significantly higher for the organic soil than for the conventional system. HWE prepared from both soils contained almost the same amounts of total N, but microbial biomass-N was higher in the organic soil. These results indicate that organically managed soils can maintain a high biological activity and substantial pools of readily available nitrogen even without application of animal manures.

Effects of AM Fungi and Plant Growth-promoting Rhizobacteria on Enzymatic Activities of Soil under Turmeric (Curcuma longaL.) Cultivation

Rhizomes of turmeric (Curcuma longa L.) are widely used for their medicinal as well as flavoring properties and in order to concentrate on biological means of promoting turmeric cultivation in Assam, a greenhouse experiment was conducted to evaluate the effects of native arbuscular mycorrhizal fungi (Glomus, Gigaspora and Acaulospora sp.) sourced from turmeric rhizosphere along with phosphate solubilizers (Bacillus megaterium) and nitrogen fixers (Azospirillum amazonense and Azotobacter sp.) on soil enzyme activities and microbial characteristics of soil under turmeric cultivation. The single, dual and consortium inoculations showed higher enzyme activities over control. Results revealed an increase in phosphatase (18.3–21.3 μmol p-nitrophenol g−1 h−1), dehydrogenase (83.4–100.5 nmol TPF g−1 h−1) and urease (83.2–99.5 μmol NH3-N g−1 h−1) enzyme activities along with an increase of 1.30–1.82 μg g−1 soil microbial biomass carbon content. Besides, mycorrhizal colonization rate showed a similar pattern in dual and consortium inoculation with single inoculation of arbuscular mycorrhizal fungi (95.2–97%) suggesting the plant growth promoting microbes as mycorrhiza helper bacteria for a clear preference as bioinoculants to be used for a sustainable agricultural strategy.

Long-term mineral fertilization impact on chemical and microbiological properties of soil and Miscanthus × giganteus yield

This experimental work was undertaken to assess the effect of various fertilization regimes (CaNPK, NPK, CaPK, CaPN, CaKN and Ca) and different soil properties on growth and yield of Miscanthus plants and to check the impact of this plant on soil microbial characteristics. Field experiment was set up in 2003 on a long-term fertilization experiment, which had been established since 1923. Miscanthus giganteus response to high soil acidity and deficiency of N, P and K was investigated. Some physico-chemical and microbiological properties of soil samples were estimated and microbial characteristics of soil were conducted to investigate the number of the following microorganisms: heterotrophic bacteria, microscopic fungi, and some diazotrophic bacteria. Obtained results showed that, the highest yield of Miscanthus was obtained from the field fertilized with the CaNPK; while the lowest one was found for plants grown without nitrogen (CaPK). The high acidity of soil and small amount of phosphorus did not affect the yields in the NPK and CaKN combinations as compared with CaNPK one. The experiments showed that Miscanthus giganteus responded positively to mineral fertilization, especially with nitrogen. The rhizosphere of Miscanthus plants provides a suitable environment for the growth and development of microorganisms, in contrast to the non-rhizosphere zone.

Effects of mushroom waste on improvement of reclaimed soil quality in coal mining areas

Restoring soil quality is the main evaluation norm of the reclamation. In order to reveal the effects of mushroom waste on the quality improvement of reclaimed soil in coal mining areas, the physical, chemical and microbial characteristics of soil are studied. The results show clear improvement in the soil after using mushroom waste. Because of human cultivation and fertilization, cultivated soil after reclamation exhibits high comprehensive quality and the index of quality of surface soil reaches 0.64 and 0.73. The average index of surface soil quality is as high as 0.52 and 0.54. In comparison, the quality of reclaimed soil of forest land is low, with average index of 0.40. The effects of mushroom waste are mainly on the surface soil in the first 2 years after the application. After that period, with the decomposition of mushroom waste, soil quality index tends to be the same as the original soil. The quality of surface soil is higher than that of subsoil, especially after the application of mushroom waste, at which point the soil quality reaches a peak at about 15 cm. Cultivated soil after reclamation has great variance in quality, after the coefficient of 24.74%. Mushroom waste can reduce such variation, particularly with long-term use. The variance efficient falls to 3.59% after 3-year application.

Short-term incorporation of organic manures and biofertilizers influences biochemical and microbial characteristics of soils under an annual crop [Turmeric (Curcuma longa L.)

The study was conducted to determine whether short-term incorporation of organic manures and biofertilizers influence biochemical and microbial variables reflecting soil quality. For the study, soils were collected from a field experiment conducted on turmeric (Curcuma longa L.) involving organic nutrient management (ONM), chemical nutrient management (CNM) and integrated nutrient management (INM). The findings revealed that application of organic manures and biofertilizers (ONM and INM) positively influenced microbial biomass C, N mineralization, soil respiration and enzymes activities. Contrarily, greater metabolic quotient levels in CNM indicated a stressed soil microbial community. Principal component analysis indicated the strong relationship between microbial activity and the availability of labile and easily mineralizable organic matter. The findings imply that even short-term incorporation of organic manures and biofertilizers promoted soil microbial and enzyme activities and these parameters are sensitive enough to detect changes in soil quality due to short-term incorporation of biological fertilizers.

Effect of Soil Type, Applications of Chicken Manure and Effective Microorganisms on Corn Yield and Microbial Properties of Acidic Wetland Soils in Indonesia

A field experiment was carried out to elucidate the effect of chicken manure (CM) and effective microorganisms (EM) on the yield of corn and chemical and microbial properties of acidic wetland soils. A split-split plot experimental design with three replications was used in this research. The main plot consisted of two types of soil. The sub-plot was for the application of CM, while the sub-sub plot was for the application of EM. Sweet corn seeds were planted and cultivated until harvest. Above ground plant biomass and round of the stem of an ear of corn were observed. Soil samples were taken and analyzed for chemical and microbial properties. The results showed that the interaction between soil types and CM application affected the corn yield, while EM had no effect. Similarly, the chemical and microbial characteristics of soils used were affected by soil type and the application of CM, while the effect of EM was not clear.

Microbial biomass and abundance after forest fire in pine forests in Japan

Microbial characteristics of soil are being evaluated increasingly as sensitive indicators of soil health because of the clear relationship between microbial diversity, soil and plant quality and ecosystem sustainability. This study aimed to determine microbial carbon biomass and microbial abundance after fire to estimate the degree of damage, including the rate of recovery of micro‐organisms, in each area. The study also aimed to establish relationships between microbial biomass and microbial abundance and the physico‐chemical properties of the soil. The study was conducted in three different study areas in Hiroshima prefecture, one unburned area and two burnt areas (one immediately after and one 2 years after fire). anova showed a significant difference in microbial carbon biomass and microbial abundance among the study areas. Microbial carbon biomass and microbial abundance were highest in the unburned area, followed by the area burnt 2 years ago and lastly by the area studied immediately after fire. Carbon biomass was highly correlated with microbial abundance (r2 = 0.950). Carbon biomass and microbial abundance were shown to be significantly correlated to the soil's physico‐chemical properties, such as pH, moisture content, water‐holding capacity and carbon : nitrogen (C : N) ratio. However, the C : N ratio was closely correlated to both carbon biomass and microbial abundance with r2 = 0.705 (P &lt; 0.01) and r2 = 0.560 (P &lt; 0.01), respectively.

Microbial characteristics of soils on a latitudinal transect in Siberia

AbstractSoil microbial properties were studied from localities on a transect along the Yenisei River, Central Siberia. The 1000 km‐long transect, from 56°N to 68°N, passed through tundra, taiga and pine forest characteristic of Northern Russia. Soil microbial properties were characterized by dehydrogenase activity, microbial biomass, composition of microbial community (PLFAs), respiration rates, denitrification and N mineralization rates. Relationships between vegetation, latitude, soil quality (pH, texture), soil organic carbon (SOC) and the microbial properties were examined using multivariate analysis. In addition, the temperature responses of microbial growth (net growth rate) and activity (soil respiration rate) were tested by laboratory experiments. The major conclusions of the study are as follows:1. Multivariate analysis of the data revealed significant differences in microbial activity. SOC clay content was positively related to clay content. Soil texture and SOC exhibited the dominant effect on soil microbial parameters, while the vegetation and climatic effects (expressed as a function of latitude) were weaker but still significant. The effect of vegetation cover is linked to SOC quality, which can control soil microbial activity.2. When compared to fine‐textured soils, coarse‐textured soils have (i) proportionally more SOC bound in microbial biomass, which might result in higher susceptibility of SOC transformation to fluctuation of environmental factors, and (ii) low mineralization potential, but with a substantial part of the consumed C being transformed to microbial products.3. The soil microbial community from the northernmost study region located within the permafrost zone appears to be adapted to cold conditions. As a result, microbial net growth rate became negative when temperature rose above 5 °C and C mineralization then exceeded C accumulation.

Evaluation of accelerated H+applications in predicting soil chemical and microbial changes due to acid rain

Abstract A comparison was made between three acidified, simulated rain treatments which have been used to assess the impact of acid rain on soil chemical and microbial processes. There were significant differences in effects on chemical and microbial characteristics of soil exposed to the three treatments due to differences in the rate of H+ ion application, even though the total quantity of protons supplied was the same in each case. An input of 30 cm of simulated rain of pH 3.0 over 6 months increased microbial activity and caused only slight changes in soil pH and soil nitrogen status. Treatments in which the rate of H+ input was accelerated by increasing solution volume, or acidity, inhibited microbial activity and caused soil chemical changes in excess of those produced by the more gradual yet equivalent H+ loading. We conclude that the effects of short‐term, accelerated acid treatments cannot be used to realistically forecast long‐term impacts of acid rain. The results of such experiments may be use...