Soil Microbial Communities and Enzyme Activities after Long-Term Application of Inorganic and Organic Fertilizers at Different Depths of the Soil Profile

Fertilization is a key factor for sustaining productivity in agroecosystems. A long-term experiment in cambisol following periodical application of several types of fertilization has been running at the experimental site since 1954. In this study, we determined the impact of applied inorganic and/or organic fertilizers on the activity of soil enzymes and on the structure of microorganisms at depths of 0-30 cm and 30-60 cm. Single-factor comparison showed that use of inorganic and/or organic fertilizer had an insignificant e_ect on the activities of soil enzymes (at depths 0-30 cm and 30-60 cm) and also on the structure of microbial communities at both depths studied. Only soil respirations exhibited stimulation by combined fertilization. The results, irrespective of sampling depth (0-60 cm), showed that application of combined organic and inorganic fertilization stimulated the activity of glucosidases and use of inorganic fertilizer inhibited the activity of arylsulphatases. Respirations were stimulated by application of organic fertilizer and combined fertilization. Nevertheless, principal component analyses, which calculate with multidimensional data, revealed di_erences in samples treated by sole mineral fertilizer compared to other variants, especially in the lower layer. In general, our results indicate that use of combined fertilization may improve biological characteristics in deeper parts of soil profile and possibly increase biological activity in agroecosystems.O

Biodegradation of High Concentrations of Aliphatic Hydrocarbons in Soil from a Petroleum Refinery: Implications for Applicability of New Actinobacterial Strains

At present, there is great demand for new resistant and metabolically active strains of biodegrading bacteria capable of degrading high concentrations of petroleum pollutants. In this study, we undertook a series of pot-based biodegradation experiments on soil from a petroleum refinery lagoon heavily polluted with aliphatic hydrocarbons (81.6 ± 2.5 g·kg−1 dry weight) and metals. Periodical bioaugmentation with either a mixture of isolated degraders identified as Bacillus sp. and Ochrobactrum sp. or biostimulation with nutrient medium, singly or in combination, did not produce any significant decrease in hydrocarbons, even after 455 days. Inoculation with Gordonia rubripertincta CWB2 and Rhodococcus erythropolis S43 in iron-limited media, however, resulted in a significant decrease in hydrocarbons 45 days after bioaugmentation. These actinobacterial strains, therefore, show significant potential for bioremediation of such highly polluted soils

Solgel Immobilization of Pseudomonas fluorescens HK44

This paper described solgel immobilization of Pseudomonas fluorescens HK44

Bioprospecting of a Novel Plant Growth-Promoting Bacterium Bacillus altitudinis KP-14 for Enhancing Miscanthus × giganteus Growth in Metals Contaminated Soil

Use of plant growth-promoting bacteria (PGPB) for cultivation of the biofuel crop Miscanthus × giganteus (Mxg) in post-military and post-mining sites is a promising approach for the bioremediation of soils contaminated by metals. In the present study, PGPB were isolated from contaminated soil and screened for tolerance against abiotic stresses caused by salinity, pH, temperature, and lead (Pb). Selected strains were further assessed and screened for plant growth-promoting attributes. The isolate showing the most potential, Bacillus altitudinis KP-14, was tested for enhancement of Mxg growth in contaminated soil under greenhouse conditions. It was found to be highly tolerant to diverse abiotic stresses, exhibiting tolerance to salinity (0–15%), pH (4–8), temperature (4–50 °C), and Pb (up to 1200 ppm). The association of B. altitudinis KP-14 with Mxg resulted in a significant (p ≤ 0.001) impact on biomass enhancement: the total shoot and dry root weights were significantly enhanced by 77.7% and 55.5%, respectively. The significant enhancement of Mxg biomass parameters by application of B. altitudinis KP-14 strongly supports the use of this strain as a biofertilizer for the improvement of plant growth in metal-contaminated soils

Fiber-Optic Chemical Sensors and Fiber-Optic Bio-Sensors

This review summarizes principles and current stage of development of fiber-optic chemical sensors (FOCS) and biosensors (FOBS). Fiber optic sensor (FOS) systems use the ability of optical fibers (OF) to guide the light in the spectral range from ultraviolet (UV) (180 nm) up to middle infrared (IR) (10 μm) and modulation of guided light by the parameters of the surrounding environment of the OF core. The introduction of OF in the sensor systems has brought advantages such as measurement in flammable and explosive environments, immunity to electrical noises, miniaturization, geometrical flexibility, measurement of small sample volumes, remote sensing in inaccessible sites or harsh environments and multi-sensing. The review comprises briefly the theory of OF elaborated for sensors, techniques of fabrications and analytical results reached with fiber-optic chemical and biological sensors

The Repetitive Detection of Toluene with Bioluminescence Bioreporter Pseudomonas putida TVA8 Encapsulated in Silica Hydrogel on an Optical Fiber

Living cells of the lux-based bioluminescent bioreporter Pseudomonas putida TVA8 were encapsulated in a silica hydrogel attached to the distal wider end of a tapered quartz fiber. Bioluminescence of immobilized cells was induced with toluene at high (26.5 mg/L) and low (5.3 mg/L) concentrations. Initial bioluminescence maxima were achieved after >12 h. One week after immobilization, a biofilm-like layer of cells had formed on the surface of the silica gel. This resulted in shorter response times and more intensive bioluminescence maxima that appeared as rapidly as 2 h after toluene induction. Considerable second bioluminescence maxima were observed after inductions with 26.5 mg toluene/L. The second and third week after immobilization the biosensor repetitively and semiquantitatively detected toluene in buffered medium. Due to silica gel dissolution and biofilm detachment, the bioluminescent signal was decreasing 20–32 days after immobilization and completely extinguished after 32 days. The reproducible formation of a surface cell layer on the wider end of the tapered optical fiber can be translated to various whole cell bioluminescent biosensor devices and may serve as a platform for in-situ sensors

Preliminary Results on Growing Second Generation Biofuel Crop Miscanthus X Giganteus at The Polluted Military Site in Ukraine

The semi-field research on using second-generation biofuel crop Miscanthus x giganteus for restoration of former military site in Kamenetz-Podilsky, Ukraine was carried out during two vegetation seasons. Despite high metal pollution of soil, in particular, by Fe, Mn, Ti, and Zr, no growth inhibition was observed. The concentrations followed pattern soil > roots > stems > leaves. Accumulation of particular metals in roots was different: Fe, Mn and Ti were accumulated rather palpably after the first vegetation season and less tangible after the second one. Cu, Pb and Zn were less accumulative in both vegetation seasons, and for As and Pb the accumulative concentrations were very small. Accumulations in the aboveground parts of the plant in comparison to roots were significantly lower in case of Fe, Ti, Mn, Cu, Zn, Sr and even statistically comparable to zero in case of As, Pb and Zr. Calculated translocation ratio of metals in the plant’s parts preferably indicated lack of metals’ hyper accumulation. Generally, no correlations were observed between concentrations of metals in the soil and in the upper plant’s parts. The research confirmed the ability of Miscanthus x giganteus to grow on the military soils predominantly contaminated by metals

State of Brownfields in the Northern Bohemia, Saxony and Lower Silesian Regions and Prospects for Regeneration by Utilization of the Phytotechnology with the Second Generation Crops

The need to achieve the sustainability goals and to reduce the continuous exploitation of the limited urban areas increases requests for the regeneration of brownfields. The current study aims to review the state of brownfields in the Northern Czech Region and neighboring German (Saxony) and Polish (Silesian) Regions which share a common geological background and environmental problems. The peculiarities of the brownfield’s properties related to the term, classification, legislative framework, access to available data, degree of contamination, and remediation methods were the focus of this review. It was established that the state with brownfield identification and transformation is better in the Czech Republic, followed by Germany, with lower awareness in Poland. The relevant examples of successful brownfield revitalization and the importance of educational components were introduced. A prospective application of the phytotechnology with the second-generation crops for the remediation of brownfields was discussed. The utilization of Miscanthus spp. for marginal lands with low contamination can provide an economic return by having biomass converted into energy or bioproducts and the utilization of the accompanied waste as carbon-rich biochar which can indeed support phytoremediation, enhance plants’ growth and serve as a medium for carbon sequestration. The next steps in the research have to concentrate on comparison of the rehabilitation methods introduced for the targeted regions with the global approach in brownfield redevelopment along with the practical ensuring the phytotechnology potential at the selected brownfields

Indication of Importance of Including Soil Microbial Characteristics into Biotope Valuation Method

Soil is a key part of a biotope and microorganisms are dominant components contributing to soil functions. Conversely, established methods for valuation of biotopes according to Natura 2000 rely predominantly on the communities living on the surface. Here, we aimed to assess soil microbial biomass and community structure on five localities with range of biotope values by means of phospholipid fatty acid (PLFA) profiling. PLFA figures were affected both by sampling season (spring vs. autumn) and locality. In spring, the living microbial biomass (estimated by PLFAtot) exhibited poor correlation to biotope values. These were, on the contrary, correlated to trans/cis PLFA, an indicator of microbial stress, (i.e., lower stress in higher-rated biotopes), and fungal/bacterial PLFA (i.e., higher-rated biotopes contained more fungi). The attempt to model biotope values from microbial characteristics explained a maximum of ~50% of the variability; the best predictors were the trans/cis stress indicator, percentage of actinobacterial PLFA, and ratio of PLFA of Gram-positive to Gram-negative bacteria. These results show that soil microbial characteristics present partly new information and indicate the need to amend the procedures of biotope assessment. Soil PLFA profiling could serve as suitable methods for this purpose