Ewa Szara

Bio: Ewa Szara is an academic researcher from Warsaw University of Life Sciences. The author has contributed to research in topics: Soil water & Sorption. The author has an hindex of 8, co-authored 38 publications receiving 246 citations. Previous affiliations of Ewa Szara include University of Warsaw.

Technogenic soils (Technosols) developed from fly ash and bottom ash from thermal power stations combusting bituminous coal and lignite. Part I. Properties, classification, and indicators of early pedogenesis

Abstract: Large amounts of fossil fuel combustion wastes (e.g. fly and bottom ash) are discharged on land surface all over the world. The uppermost layer of disposal sites is subject to soil-forming processes after the development of plant cover due to natural succession or reclamation works. The present study presents the analysis of technogenic soils (Technosols) developed from ashes after combustion of bituminous coal and lignite. The study involved the determination of their properties, their classification, and discussion of the indicators of early pedogenesis. Technosols located on the surface of settling ponds and landfills of selected thermal power stations in Poland combusting both bituminous coal and lignite were examined. Standard pedological methods for the determination of soil morphology and physical-chemical properties were applied. Dithionite and oxalate extractions of Fe, Al, Si, and Mn were used in order to determine transformations of soil substrate during pedogenesis. Moreover, optical microscope observations permitted finding microscale effects of soil-forming processes in the studied Technosols. The properties of the analysed Technosols are primarily influenced by the properties of the parent material (i.e. ash from thermal power stations) which in turn are strongly dependent on (1) the type of ash (fly ash vs. bottom ash), (2) the kind of fuel (bituminous coal vs. lignite), as well as (3) the mode of ash deposition and type of disposal site (settling pond vs. dry landfill). Properties of the studied soils are also controlled by the following soil-forming factors: vegetation (input of soil organic matter), human (acceleration of soil-forming processes by reclamation), and climatic/weather conditions (leaching of soluble compounds by water from precipitation). The most important morphological and physical-chemical indicators of pedogenesis of the studied Technosols over several decades of soil formation are as follows: (1) the development of soil structure in A horizon related to the accumulation of soil organic matter, (2) the decrease in pH (a change in reaction from strongly alkaline towards less alkaline or acidic), (3) the formation of pedogenic carbonates and their subsequent leaching from the topsoil after several dozen of years of pedogenesis, and (4) the release of oxalate-extractable Al and Si during the pedogenesis. The studied soils were classified according to WRB as Spolic Technosols (or Leptic Spolic Technosols) with various supplementary qualifiers (Alcalic or Eutric, Arenic and/or Loamic, Calcic or Protocalcic, Fluvic, Hyperartefactic, Laxic, Relocatic, Tephric or Vitric). Certain suggestions to improve the WRB soil system are discussed in the paper.

Struvite—An Innovative Fertilizer from Anaerobic Digestate Produced in a Bio-Refinery

Abstract: This paper presents the results of a pot experiment aimed at the assessment of the fertilizer value of struvite, a precipitation product obtained from a liquid fraction of the digestate. The effects of struvite (STR), struvite + ammonium sulphate (STR + N) and ammonium phosphate (AP) treatments were examined on maize and grass cultivation on silty loam and loamy sand soil. The crop yields were found to depend on both the soil type and experimental treatment. Crop yields produced under STR and STR + N exceeded those under the control treatments by respectively 66% and 108% for maize, and 94% and 110% for grass. Crop yields under STR + N were similar or greater than those under the AP treatment. The nitrogen recovery by maize and grass reached respectively 68% and 62% from the struvite and 78% and 52% from AP. The phosphorus recovery by maize and grass reached 7.3% and 4.8%, respectively, from struvite (i.e., STR and STR + N), which was lower than that from the AP (18.4% by maize and 8.1% by grass).

A Bio-Refinery Concept for N and P Recovery—A Chance for Biogas Plant Development

Abstract: Biogas is an alternative source of energy for fossil fuels. In the process of transforming organic materials into biogas significant amounts of valuable digestate are produced. In order to make the whole process sustainable digestate should be utilized this is a constraining factor in the development of the biogas industry. Consequently, there is an on-going search for new technologies to process digestate, allowing to broaden the range of possible ways of digestate utilization. One of such possibilities is technology of nitrogen (N) and phosphorus (P) recovery from the anaerobic digestate. In this study results of physicochemical analysis of materials flowing through the farm-scale bio-refinery producing struvite (STR) and ammonium sulphate (AS) are presented. Struvite was precipitated from the liquid fraction of digestate (LFDS). Ammonia was bound by sulphuric acid resulting in obtaining ammonium sulphate. The STR obtained was of medium purity and contained other macronutrients and micronutrients that further enhanced its agronomic value. The P recovery effectiveness, counted as the difference between the Ptot content in the material before and after STR precipitation was 43.8%. The AS was characterized by relatively low Ntot and Stot content. The Ntot recovery efficiency reached 43.2%. The study showed that struvite precipitation and ammonia stripping technologies can be used for processing digestate however, the processes efficiency should be improved.

Nitrous oxide emissions from the soil under different fertilization systems on a long-term experiment

Abstract: The research aimed at the assessment of N 2 O emission from agricultural soils subject to different fertilization conditions. It was carried out on a long-term experiment field in Skierniewice in Central Poland maintained with no alterations since 1923 under rye monoculture. The treatments included mineral (CaNPK), mineral-organic (CaNPK + M) and organic (Ca + M) fertilization. Measurements were conducted during the growing periods of 2012 and 2013. N 2 O emissions from the soil were measured in situ by the means of infrared spectroscopy using a portable FTIR spectrometer Alpha. N 2 O fluxes over the measurement periods showed high variability with range 0.13-11.20 g N 2 O-N/ha/day (median 2.87, mean 3.16) from mineral treated soil, 0.23-11.06 g N 2 O-N/ha/day (median 3.64, mean 3.33) from mineral-organic treated soil and 0.25-12.28 g N 2 O-N/ha/day (median 3.14, mean 3.55) from organic treated soil. N 2 O fluxes from manure-treated soils were slightly higher than those from soils treated exclusively with mineral fertilizers. N 2 O fluxes were positively correlated with soil temperature, air temperature, and content of both, N 3 O- and NH 4 + , in the soil (0-25 cm) and, to a lesser degree, negatively correlated with soil moisture. Based on the measured N 2 O flux and its relationship with environmental factors it can be concluded that both, nitrification and denitrification the are important sources of N 2 O in mineral soils of Central Poland, where the average soil water-filled pore space during the growing period range from 22-35%. Under the climate, soil and fertilization conditions in Central Poland, the N 2 O emission from cultivated soils during the growing period is approximately estimated as 0.64-0.73 kg N/ha.

Global increasing trends in annual maximum daily precipitation

Abstract: This study investigates the presence of trends in annual maximum daily precipitation time series obtained from a global dataset of 8326 high-quality land-based observing stations with more than 30 years of record over the period from 1900 to 2009. Two complementary statistical techniques were adopted to evaluate the possible nonstationary behavior of these precipitation data. The first was a Mann‐Kendall nonparametric trend test, and it was used to evaluate the existence of monotonic trends. The second was a nonstationary generalized extreme value analysis, and it was used to determine the strength of association between the precipitation extremes and globally averaged near-surface temperature. The outcomes are that statistically significant increasing trends can be detected at the global scale, with close to two-thirds of stations showing increases. Furthermore, there is a statistically significant association with globally averaged near-surface temperature,withthemedianintensityofextremeprecipitationchanginginproportionwithchangesinglobal mean temperature at a rate of between 5.9% and 7.7%K 21 , depending on the method of analysis. This ratio was robust irrespective of record length or time period considered and was not strongly biased by the uneven global coverage of precipitation data. Finally, there is a distinct meridional variation, with the greatest sensitivity occurring in the tropics and higher latitudes and the minima around 138S and 118N. The greatest uncertainty was near the equator because of the limited number of sufficiently long precipitation records, and there remains an urgent need to improve data collection in this region to better constrain future changes in tropical precipitation.

Feedstock choice, pyrolysis temperature and type influence biochar characteristics: a comprehensive meta-data analysis review

Abstract: Various studies have established that feedstock choice, pyrolysis temperature, and pyrolysis type influence final biochar physicochemical characteristics. However, overarching analyses of pre-biochar creation choices and correlations to biochar characteristics are severely lacking. Thus, the objective of this work was to help researchers, biochar-stakeholders, and practitioners make more well-informed choices in terms of how these three major parameters influence the final biochar product. Utilizing approximately 5400 peer-reviewed journal articles and over 50,800 individual data points, herein we elucidate the selections that influence final biochar physical and chemical properties, total nutrient content, and perhaps more importantly tools one can use to predict biochar’s nutrient availability. Based on the large dataset collected, it appears that pyrolysis type (fast or slow) plays a minor role in biochar physico- (inorganic) chemical characteristics; few differences were evident between production styles. Pyrolysis temperature, however, affects biochar’s longevity, with pyrolysis temperatures > 500 °C generally leading to longer-term (i.e., > 1000 years) half-lives. Greater pyrolysis temperatures also led to biochars containing greater overall C and specific surface area (SSA), which could promote soil physico-chemical improvements. However, based on the collected data, it appears that feedstock selection has the largest influence on biochar properties. Specific surface area is greatest in wood-based biochars, which in combination with pyrolysis temperature could likely promote greater changes in soil physical characteristics over other feedstock-based biochars. Crop- and other grass-based biochars appear to have cation exchange capacities greater than other biochars, which in combination with pyrolysis temperature could potentially lead to longer-term changes in soil nutrient retention. The collected data also suggest that one can reasonably predict the availability of various biochar nutrients (e.g., N, P, K, Ca, Mg, Fe, and Cu) based on feedstock choice and total nutrient content. Results can be used to create designer biochars to help solve environmental issues and supply a variety of plant-available nutrients for crop growth.

Stimulation of N2O emission by manure application to agricultural soils may largely offset carbon benefits: a global meta-analysis

Abstract: Animal manure application as organic fertilizer does not only sustain agricultural productivity and increase soil organic carbon (SOC) stocks, but also affects soil nitrogen cycling and nitrous oxide (N2O) emissions. However, given that the sign and magnitude of manure effects on soil N2O emissions is uncertain, the net climatic impact of manure application in arable land is unknown. Here, we performed a global meta-analysis using field experimental data published in peer-reviewed journals prior to December 2015. In this meta-analysis, we quantified the responses of N2O emissions to manure application relative to synthetic N fertilizer application from individual studies and analyzed manure characteristics, experimental duration, climate, and soil properties as explanatory factors. Manure application significantly increased N2O emissions by an average 32.7% (95% confidence interval: 5.1-58.2%) compared to application of synthetic N fertilizer alone. The significant stimulation of N2O emissions occurred following cattle and poultry manure applications, subsurface manure application, and raw manure application. Furthermore, the significant stimulatory effects on N2O emissions were also observed for warm temperate climate, acid soils (pH < 6.5), and soil texture classes of sandy loam and clay loam. Average direct N2O emission factors (EFs) of 1.87% and 0.24% were estimated for upland soils and rice paddy soils receiving manure application, respectively. Although manure application increased SOC stocks, our study suggested that the benefit of increasing SOC stocks as GHG sinks could be largely offset by stimulation of soil N2O emissions and aggravated by CH4 emissions if, particularly for rice paddy soils, the stimulation of CH4 emissions by manure application was taken into account.

Mapping of research lines on circular economy practices in agriculture: From waste to energy

Abstract: Agriculture is one of the sectors that strongly contribute to greenhouse gas emissions on the planet. In this sense, circular economy practices can be advantageous when using bioenergy in the agro-industrial sector. Although only about 9% of the world's economy is circular, global initiatives have acted to change that scenario. Unlike the linear economy (take-make-use-dispose), the circular economy (grow-make-use-restore) aims to influence material and energy flows to increase environmental gains and avoid costs. Based on that, this study aims to map bioenergy boosters through circular economy practices in agriculture. To that end, a systematic literature review was conducted to present what is being developed in this field. To identify the most relevant, high impact, studies in the area, the systematic literature review was performed in three databases, covering all available literature up to date. The main research themes, applications, research topics, area of activity, countries, journals, publisher, and history of publication were identified. Therewith, some trends and perspectives could be drawn. To date, no solidly established authors have been identified in the area. The theme is recent and the vast majority of documents have been published over the last four years. European countries have been pioneering and are the most prominent in terms of publications. The electricity generation and biofuel produced from biogas have shown representativeness and are sustainable opportunities to advance the theme. Therefore, this study can contribute to encouraging the agricultural sector in implementing or increasing the use of circular economy practices.