Magdalena Vaverková

Effect of inoculation with white-rot fungi and fungal consortium on the composting efficiency of municipal solid waste

An investigation was carried out on the effect of inoculation methods on the compost of an organic fraction of municipal solid waste. Three types of white-rot fungi (Phanerochaete chrysosporium, Trametes versicolor and Fomes fomentarius), and a consortium of these fungi, were used. The study assessed their influence on microbial enzymatic activities and the quality of the finished compost. It was found that the addition of white-rot fungi to municipal solid waste (after 37days of composting) could be a useful strategy for enhancing the properties of the final compost product. In comparison with the control sample (compost without inoculation), it accelerates degradation of solid waste as indicated by changes in C/N, electrical conductivity and pH. However, the effectiveness of waste degradation and compost maturation depends on the type of microorganism used for inoculation. The presence of inoculants, such as Trametes versicolor and Fomes fomentarius, led to a higher degrading ratio and a better degree of maturity. This resulted in an increase of enzymatic activities (especially dehydrogenase and protease) and a germination index in comparison with inoculation using Phanerochaete chrysosporium or a consortium of fungi.

Evaluation of biodegradability of plastics bags in composting conditions

Abstract Biodegradation of plastics bags advertised as 100%-degradable or certified as compostable was tested in composting conditions. Samples were placed into frames and inserted into one clamp within the compost pile to investigate the biodegradation. The plastics bags were obtained from chain stores in the Czech Republic and Poland. The shopping bags were made of HDPE with the TDPA additive (sample 2), PP with an addition of pro-oxidants (d2w) (samples 1, 3) and materials certified as compostable (starch, polycaprolactone) (samples 4, 5, 6, 7). Control sample (cellulose filtering paper, sample 8) was to check the potential of biological decomposition in the tested environment. At the end of the 12-week experimental period it was found that the polyethylene samples with the additive (samples 1, 2, 3) had not been decomposed, their colour had not changed and that no degradation neither physical changes had occurred (did not biodegrade). Samples certified as compostable (samples 4, 5, 6, 7) were decomposed. The results at the municipal compost facility demonstrate that the compostable plastics biodegrade and polyethylene samples with the additive did not biodegrade in compost. Abstrakt Badano biodegradację plastikowych toreb reklamowych ulegających w 100% rozkładowi oraz certyfikowanych jako kompostowalne w warunkach kompostowania. W celu oceny biodegradacji próbki zostały umieszczone w ramach, a następnie w materiale przeznaczonym do kompostowania. Plastikowe torby są dostępne w sieci sklepów w Czechach, jak również w Polsce. Badaniu poddano osiem próbek. Jedną z nich była jednorazowa torba wykonana z folii HDPE z dodatkiem TDPA (próbka 2). Kolejne torby były wykonane z polietylenu z dodatkiem oxo-biodegradacji d2w (próbki 1, 3). Cztery próbki posiadały certyfikat kompostowalności (próbki 4, 5, 6, 7). Próbka ósma była próbką kontrolną (celulozowy papier filtracyjny, próbka 8), która miała na celu sprawdzenie potencjału biologicznego rozkładu badanego środowiska. Test został przeprowadzony w warunkach kompostowni przemysłowej. Pod koniec 13-tygodniowego okresu doświadczalnego stwierdzono, że próbki z polietylenu (próbki 1, 2, 3) nie uległy rozkładowi, ich barwa się nie zmieniła oraz że nie ma zmian fizycznych potwierdzających degradację. Próbki posiadające certyfikat kompostowalności (próbki 4, 5, 6, 7) uległy rozkładowi w różnym stopniu. Z przeprowadzonego doświadczenia wynika, że kompostowalne torby uległy rozkładowi, a torby wykonane z polietylenu z dodatkiem TDPA oraz d2w nie ulegają rozkładowi w kompoście.

Phytostabilization—Management Strategy for Stabilizing Trace Elements in Contaminated Soils

Contamination of soil by copper (Cu) has become a serious problem throughout the world, causing the reduction of agricultural yield and harmful effects on human health by entering the food chain. A glasshouse pot experiment was designed to evaluate the potential use of halloysite as an immobilizing agent in the aided phytostabilization of Cu-contaminated soil, using Festuca rubra L. The content of Cu in plants, i.e., total and extracted by 0.01 M CaCl2, was determined using the method of spectrophotometry. Cu content in the tested parts of F. rubra differed significantly when halloysite was applied to the soil, as well as with increasing concentrations of Cu. The addition of halloysite significantly increased plant biomass. Cu accumulated in the roots, thereby reducing its toxicity to the aerial parts of the plant. The obtained values of bioconcentration and translocation factors observed for halloysite treatment indicate the effectiveness of using F. rubra in phytostabilization techniques.

THE TOXICITY OF TWO TYPES OF SEWAGE SLUDGE FROM WASTEWATER TREATMENT PLANT FOR PLANTS IN CZECH REPUBLIC

The aim of the present study was the estimation of the phytotoxicity of soils amended with sewage sludge with relation to Sinapis alba L. The study was realized in the system of a plot experiment. Two kinds of sewage sludge: dewatered and anaerobically stabilized sludge with dry matter content of about 24%, and dewatered sludge “Palikal” with dry matter content of about 92%. The results indicate that the tested samples are toxic. Growth inhibition at the studied samples ranged from 70.45% to 100%.

DOES COMPOSTING OF BIODEGRADABLE MUNICIPAL SOLID WASTE ON THE LANDFILL BODY MAKE SENSE

In this study white mustard (Sinapis alba) plants were allowed to grow in earthen pots, treated with municipal solid waste compost (MSWC) to study the effect of MSWC on the plant biomass production. Twenty-one days from the establishment of the experiment sprouts and the number of growing plants occurring in the earthen pots were counted. Plants growing in the earthen pots with the compost samples exhibited an increasing plant biomass while no changes were observed in their appearance; retarded growth or necrotic changes were not recorded. The performed phytotoxicity tests show that the analyzed composts produced in the composting plant situated on the landfill surface achieved high percentages of the germinating capacity of white mustard (Sinapis alba) seeds and can be therefore used in the subsequent reclamation of the concerned landfill.

Biodegrability of Bioplastic Materials in a Controlled Composting Environment

The objective of this study was to determine the biodegradability of bioplastic materials – sponge cloths – available on the European market that are labeled as 100% biodegradable but not certified as compostable. The test was carried out in a controlled composting environment. The project length was 22 weeks. The emphasis was put on discovering whether the sponge cloths are biodegradable or not. Based on the results thereof it can be concluded that sponge cloths have not decomposed completely but their color has changed and that degradation and physical changes occurred. Samples A1, and A2 have not decomposed completely and exhibited very slow degradation rate. Sample B5 exhibited the highest degradation rate. Samples B3, B4 exhibited high degree of decomposition. The main conclusion from this study is that biodegradation of bioplastics materials strongly depends on both the environment in which they are placed and the chemical nature of the material.

Evaluation of landfill pollution with special emphasis on heavy metals

Monitoring leachate, groundwater and surface water aiming to determinate the concentration of heavy metals (Hg, Zn, Ni, Cr 6+ ,Cd, Pb) at the municipal solid waste landfill Stěpanovice took place in the years 2002–2010. The values of heavy metals concentration oscillated as follows: Zn (0.05 – 0.37 μg/dm 3 ), Cr +6 (0.01 – 3.3 μg/dm 3 ), Hg (0.0001 – 0.001 (μg/dm 3 ), Ni (0.001 – 0.19 μg/dm 3 , Cd (0.001 – 0.007 μg/dm 3 ) and Pb (0.002 – 0.176 μg/dm 3 ). The measured data show that the concentrations of heavy metals met the limits provided by law. Under the current landfill operation mode, the results of measurements do not indicate any negative impact on the quality of surface water, groundwater or leachate water.

Evaluation of landfill leachate pollution: findings from a monitoring study at municipal waste landfill

The monitoring that was carried out at the landfill specialized in leachate, groundwater and surface water. There were 6 sampling sites. The observed parameters were pH, BOD5, CODCr, conductivity. Leachate reached the high values in all observed parameters. Groundwater samples were collected at two monitoring wells and the sampling site (A, B, C). Surface water was collected from two sampling sites (D, E). The pH showed slightly acid values at all sampling points. The pH of surface water was slightly acid to neutral. Both BOD5 and CODCr values remained stable over the reporting period. The average conductivity value at sampling points D, E remained constant. In line with the Czech National Standard CSN 75 7221 “Classification of Surface Water Quality” sampling point D belongs to II Water Quality Class – slightly polluted water and sampling site E to Class I water quality – unpolluted water. The authors believe that the fluctuations occurring with regard to the values of certain samples were not caused by the operation of the landfill itself, but were a result of the intense agricultural activity nearby the landfill.

Influence of Fertilization on Microbial Activities, Soil Hydrophobicity and Mineral Nitrogen Leaching

Abstract This work presents the analysis of the influence of compost and reclamation substrate addition and mineral fertilizers application on leaching of mineral nitrogen, microbial activities, soil hydrophobicity and plant biomass production. To demonstrate the effect of compost, reclamation substrate and mineral nitrogen (Nmin) addition on above parameters, the pot experiment was performed. As a model crop, Deschampsia caespitosa L. was used and cultivated for 63 days in climate chamber. The leaching of Nmjn was measured by application of ion exchange discs, soil hydrophobicity was determined based on the values of saturated hydraulic conductivity (Ksat) and microbial activity was expressed as basal (BR) and substrate induced respiration (SIR). Four variants (V1-V4) with different doses of fertilizers were prepared: V1 - control without addition of fertilizers; V2 - this variant of experiment was prepared as mixture of compost and arable land in ratio 7:3; V3 - 90 g/m2 of mineral fertilizers NPK (in the ratio 1:1:1) were applied there and into V4, dose 30 g of compost were applied. The significant differences (P < 0.05) in the detection of Nmin, values of Ksat and SIR were found. The highest decrease of mineral nitrogen leaching was observed by the simultaneous applications of compost (V4) to arable soil, about 50% in comparison with the variant V4 (application of mineral fertilization) and about 10% in comparison with the control. Variants with addition of compost (V2 and V4) showed higher values than variants without, which were measured at three stages (before application of Nmin - 12 days after establishment of the experiment; after application of Nmin - 34 days; at end of the experiment - 63 days). During the experiment, two types of respiration were measured: BR and SIR. The significant differences in SIR were found between variants with addition of compost and variants without. The SIR (cumulative production of CO2) was higher about 25% in variants V2 and V4 compared to variants V1 and V3. The highest values of Ksat were found in variants with addition of compost. Conversely, the lowest value of Ksat was detected in variant with addition of Nmin. Low values of Ksat indicate an increased level of hydrophobicity.

HOW DO DEGRADABLE/BIODEGRADABLE PLASTIC MATERIALS DECOMPOSE IN HOME COMPOSTING ENVIRONMENT?

This paper provides information about biodegradability of polymeric (biodegradable/ degradable) materials advertised as 100%-degradable or certified as compostable, which may be a part of biodegradable waste, in home composting conditions. It describes an experiment that took place in home wooden compost bins and contained 9 samples that are commonly available in retail chains in the Czech Republic and Poland. The experiment lasted for the period of 12 weeks. Based on the results thereof it can be concluded that polyethylene samples with additive (samples 2, 4, 7) have not decomposed, their color has not changed and that no degradation or physical changes have occurred. Samples 1, 3 and 5 certified as compostable have not decomposed. Sample 6 exhibited the highest decomposition rate. Samples 8, 9 (tableware) exhibited high degree of decomposition. The main conclusion from this study is that degradable/biodegradable plastics or plastics certified as compostable are not suitable for home composting.