The Influence of Microbial Degradation of Biochar in Soil on its Physico-chemical Properties

This master‘s thesis studies the different factors that can affect biochar in soil and cause its degradation. These factors include irrigation, root exudates and the action of microorganisms. In the experimental part, the degradation of biochar in the soil environment was studied in two ways, firstly without the action of microorganisms, where the effect of irrigation was simulated by leaching biochar in ultrapure distilled water and model rainwater, and the effect of root exudates was simulated by extracting of biochar in citric acid as a model root exudate of maize sown. The extracted biochar solutions without prior cultivation in soil were characterized by pH, conductivity, UV-VIS analysis and elemental analysis. The biochar residues after extractions were characterized for morphology by SEM, structural differences by FTIR, and organic and mineral content by TGA analysis. The biochar samples after cultivation in soil were subjected to extractions under the same conditions and the same analyses were performed. The effect of cultivation in soil on biochar resulted in a change in elemental composition, a decrease in biochar alkalinity and changes in the ratio of organic matter and mineral fraction were observed. The decrease in pH and conductivity of biochar was mainly related to potassium leaching. The structural and morphological analysis indicated that there is no significant degradation of the structure of the biochar due to washing or cultivation in soil, but there is a partial fouling of the biochar pores by low molecular weight impurities from the soil. These results suggest a short-term action of biochar in soils as a source of nutrients (potassium, phosphorus) and, conversely, a long-term action as a soil conditioner

Study on the Effect of Biochar Application on Organic Matter in Soil

Tato bakalářská práce studuje, jaký vliv má aplikace biouhlu na složení organické hmoty dvou rozdílných vzorků půd. Konkrétně byl sledován celkový obsah organické hmoty v půdě a poměr huminových a fulvinových kyselin v těchto půdách před a po aplikaci biouhlu. Složení půdní hmoty bylo pozorováno termogravimetricky a také na základě využití certifikované metodiky izolace huminových a fulvinových kyselin ze vzorků studovaných půd. Dále byl pozorován vliv biouhlu na růst modelové rostliny (kukuřice setá – Zea mays), kdy už od počátku experimentu bylo možné pozorovat rozdíly v růstu, a to jak v porovnání vzorků s biouhlem a bez biouhlu, tak také v porovnání vzorků s různou dávkou biouhlu. Vliv na růst rostlin měl také druh půdy, která byla využita pro kultivační experimenty.This bachelor thesis studies the effect of the application of biochar on the composition of organic matter of two different soil samples. Specifically, the total content of organic matter in the soil and the ratio of humic and fulvic acids in these soils before and after the application of biochar were monitored. The composition of the soil mass was also observed thermogravimetrically and by using the certified method of humic and fulvic acids isolation from samples of studied soils. Furthermore, the effect of biochar on the growth of a model plant (maize – Zea mays) was observed. From this point of view, differences in plant growth were possible to observe from the beginning of the experiment, both in comparison with samples with and without biochar and in comparison with samples containing different doses of biochar. The type of soil used for cultivation experiments also influenced on plant growth.

The Influence of Microbial Degradation of Biochar in Soil on its Physico-chemical Properties

Tato diplomová práce studuje jednotlivé činitele, které mohou působit na biouhel v půdě a působit jeho degradaci. Mezi tyto činitele patří závlaha, kořenové exsudáty a působení mikroorganismů. V experimentální části byla degradace biouhlu v půdním prostředí studována dvojím způsobem, nejprve bez působení mikroorganismů, kdy vliv závlahy byl simulován výluhy biouhlů v ultračisté destilované vodě a modelové dešťové vodě, a vliv kořenových exsudátů byl simulován extrakcemi biouhlů v kyselině citronové, jakožto modelového kořenového exsudátu kukuřice seté. Extrahované roztoky biouhlů bez předchozí kultivace v půdě byly charakterizovány pomocí pH, vodivosti, UV-VIS analýzy a prvkové analýzy. U zbytků biouhlů po extrakcích byla charakterizována morfologie pomocí SEM, strukturní změny pomocí FTIR a obsah organiky a minerální části pomocí TGA analýzy. Na vzorcích biouhlů po kultivaci v půdě byly provedeny extrakce za stejných podmínek a byly provedeny tytéž analýzy. Vlivem kultivace v půdě u biouhlů došlo ke změně prvkového složení, poklesu alkality biouhlu a byly pozorovány změny poměru organické hmoty a minerální složky. Pokles pH a vodivosti biouhlů souvisí zejména s vyluhováním draslíku. Strukturní a morfologická analýza naznačila, že vlivem promývání ani kultivací v půdě nedochází k výraznější degradaci jeho struktury, ale dochází k částečnému zanášení pórů biouhlů nízkomolekulárními nečistotami z půdy. Tyto výsledky naznačují krátkodobé působení biouhlů v půdách jakožto zdroj živin (draslík, fosfor) a naopak dlouhodobé působení jakožto půdní kondicionér.This master‘s thesis studies the different factors that can affect biochar in soil and cause its degradation. These factors include irrigation, root exudates and the action of microorganisms. In the experimental part, the degradation of biochar in the soil environment was studied in two ways, firstly without the action of microorganisms, where the effect of irrigation was simulated by leaching biochar in ultrapure distilled water and model rainwater, and the effect of root exudates was simulated by extracting of biochar in citric acid as a model root exudate of maize sown. The extracted biochar solutions without prior cultivation in soil were characterized by pH, conductivity, UV-VIS analysis and elemental analysis. The biochar residues after extractions were characterized for morphology by SEM, structural differences by FTIR, and organic and mineral content by TGA analysis. The biochar samples after cultivation in soil were subjected to extractions under the same conditions and the same analyses were performed. The effect of cultivation in soil on biochar resulted in a change in elemental composition, a decrease in biochar alkalinity and changes in the ratio of organic matter and mineral fraction were observed. The decrease in pH and conductivity of biochar was mainly related to potassium leaching. The structural and morphological analysis indicated that there is no significant degradation of the structure of the biochar due to washing or cultivation in soil, but there is a partial fouling of the biochar pores by low molecular weight impurities from the soil. These results suggest a short-term action of biochar in soils as a source of nutrients (potassium, phosphorus) and, conversely, a long-term action as a soil conditioner.

Application of mathematical models for simulation of hydrological conditions in selected streams

Flood is a natural phenomenon that occurs at different intensities and irregular time intervals. As to natural disasters, floods represent the greatest direct threat for the Czech Republic. They may cause serious critical situations during which not only extensive material damages are done, but may bring also losses of the lives of inhabitants in affected areas as well as vast devastation of cultural landscape including environmental damages. Important from the viewpoint of the elimination of potential threats and consequences of such events is the information issued by flood forecasting service about the character and size of flood areas for individual N-year flood discharges and specific flood scenarios. An adequate image of depths and flow rates in the longitudinal or cross profile of the watercourse during a flood event is provided by the hydrodynamic model. This is why the information obtained from the hydrodynamic models occupies a privileged position from the viewpoint of the protection of citizens' lives and mitigation of damage to their property. The first study is situated on the river Úhlava in meadows by Příchovice near the town Přeštice. The proposal of flood-protection measures is contained in Territorial control documentation. The documentation was elaborated on the basis of hydraulic calculations and experiences from the flood in August 2002. The mathematical model is practically used in the study of analysis of proposed flood-protection measures. The analysis is based on mathematical simulation of water outflow and water level on the river Úhlava. It is possible to use the non-commercial software Hec-Ras, version 3.1.1., for the simulation itself. One of the points of view of the possibility of using proposed flood-protection measures is total efficiency. The mathematical model is posssible to use as a basis of support for realization of proposed flood-protection measures on the river Úhlava in meadows by Příchovice within the grant programme "Program prevence před povodněmi II" under the control of the Ministry of Agriculture. In the second case the mathematical model is practically used in the study of hydrotechnical analysis of streams in cadastral unit. The analysis is based on matjematical simulation of water outflow and water level on chosen streams. It is possible to use the noncomercial software HEC-RAS for the own simulation. The analysis should be shown on dangerous places in the interest place. The mathematical model is possible of using to use as basis for revaluation of action in spatial plan or for view of the flood-protection measures in the village Mochtín. Basic input into the hydrodynamic models is represented by altimetry data. One of ways to obtain such data is through the method of aerial laser scanning (ALS) from the digital relief model (DRM). This method is considered one of the most accurate methods for obtaining altimetry data. Its bottleneck is however incapacity of recording terrain geometry under water surface due to the fact that laser beam is absorbed by water mass. The absence of geometric data on watercourse discharge area may perceptibly affect results of modelling, especially if a missing part of the channel represents a significant discharge area with its capacity. One of methods for eliminating the deficiency is a sufficient channel recess by means of software tools such as CroSolver. The third submitted paper deals with the construction of a hydrodynamic model using 5th generation DRM data, and compares outputs from this model at various discharges with a model based on the altimetry data modified by using the CroSolver tool. Outputs from the two hydrodynamic models are compared in HEC-RAS programme with the use of recessed data and with the use of unmodified DRM. The comparison is done on the sections of two watercourses with different terrain morphology and watercourse size. A complementary output is the comparison of inundation areas issuing from both model variants. Our results indicate that differences in the outputs are significant namely in the lower discharges (Q1, Q5) whereas for Q50 and Q100 the difference is negligible with a great role being played by morphology of the modelled area and by the watercourse size

Comparing a hydrodynamic model from fifth generation DTM data and a model from data modified by means of CroSolver tool

Flooding is a natural phenomenon that occurs with varying intensity and at irregular time intervals. Floods are the natural disasters that pose the greatest direct threat to the Czech Republic. They may cause serious critical situations during which not only extensive material damages are incurred, but so too is the loss of human life in affected areas as well as vast devastation of the cultural landscape including environmental damages. The information issued by flood forecasting services about the character and size of flood areas for individual N-year flood discharge events and specific flood scenarios is important for eliminating the potential threats and consequences of such events. Hydrodynamic models provide an adequate image of depths and flow velocities at the longitudinal or cross profiles of the watercourse during a flood event. This is why information obtained from hydrodynamic models occupies a privileged position from the viewpoint of protecting human life and mitigating property damage. Altimetry data are the basic input into hydrodynamic models. One way to obtain such data is through the method of aerial laser scanning (ALS) from the digital terrain model (DTM). This method is considered one of the most accurate methods for obtaining altimetry data. Its major drawback is however its inability to record terrain geometry under water surfaces due to the fact that the laser beam is absorbed by the body of water. The absence of geometric data on watercourse cross sectional area may perceptibly affect results of modelling, especially if the capacity of a missing part of the channel represents a significant cross sectional area. One of the methods for eliminating this deficiency is sufficiently calculating channel depth by means of software tools such as CroSolver. This paper deals with the construction of a hydrodynamic model using fifth generation DTM data and compares outputs from this model at various discharges with a model based on the altimetry data modified using CroSolver. Outputs from the two hydrodynamic models are compared using HEC-RAS software with the use of depth estimate data and with the use of the unmodified DTM. The comparison is done on two watercourse reaches with different terrain morphology and watercourse size. A complementary output is the comparison of inundation areas issuing from both model variants. Our results indicate that differences in the outputs are significant, namely at lower discharges (Q1, Q5), whereas at Q50 and Q100 the difference is negligible with a great role played by the morphology of the modelled area and by the watercourse size

Comparing a hydrodynamic model from fifth generation dtm data and a model from data modified by means of crosolver tool =Porovnání hydrodynamického modelu z dat DMR 5. generace a modelu z dat upravených pomocí nástroje CroSolver

Flooding is a natural phenomenon that occurs with varying intensity and at irregular time intervals. Floods are the natural disasters that pose the greatest direct threat to the Czech Republic. They may cause serious critical situations during which not only extensive material damages are incurred, but so too is the loss of human life in affected areas as well as vast devastation of the cultural landscape including environmental damages. The information issued by flood forecasting services about the character and size of flood areas for individual N-year flood discharge events and specific flood scenarios is important for eliminating the potential threats and consequences of such events. Hydrodynamic models provide an adequate image of depths and flow velocities at the longitudinal or cross profiles of the watercourse during a flood event. This is why information obtained from hydrodynamic models occupies a privileged position from the viewpoint of protecting human life and mitigating property damage. Altimetry data are the basic input into hydrodynamic models. One way to obtain such data is through the method of aerial laser scanning (ALS) from the digital terrain model (DTM). This method is considered one of the most accurate methods for obtaining altimetry data. Its major drawback is however its inability to record terrain geometry under water surfaces due to the fact that the laser beam is absorbed by the body of water. The absence of geometric data on watercourse cross sectional area may perceptibly affect results of modelling, especially if the capacity of a missing part of the channel represents a significant cross sectional area. One of the methods for eliminating this deficiency is sufficiently calculating channel depth by means of software tools such as CroSolver.This paper deals with the construction of a hydrodynamic model using fifth generation DTM data and compares outputs from this model at various discharges with a model based on the altimetry data modified using CroSolver. Outputs from the two hydrodynamic models are compared using HEC-RAS software with the use of depth estimate data and with the use of the unmodified DTM. The comparison is done on two watercourse reaches with different terrain morphology and watercourse size. A complementary output is the comparison of inundation areas issuing from both model variants. Our results indicate that differences in the outputs are significant, namely at lower discharges (Q1, Q5), whereas at Q50 and Q100 the difference is negligible with a great role played by the morphology of the modelled area and by the watercourse size.293