54 research outputs found

    Biotic interactions and biogeochemical processes in the soil environment

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    Soils play a key role in the terrestrial carbon (C) cycle by storing and emitting large quantities of C. The impact of abiotic conditions (mainly soil temperature and moisture) on soil C turnover is well documented, but unravelling the influence of these drivers across temporal and spatial scales remains an important challenge. Biotic factors, such as microbial abundance and diversity, macro-faunal food webs and below-ground plant (i.e. root) biomass and diversity, play an important role in controlling soil C storage and emission, but remain under-investigated. To better understand the soil processes underlying terrestrial C cycling, the interactions between plants (autotrophs) and soil organisms (heterotrophs) need to be addressed more explicitly and integrated with short- and long-term effects of abiotic drivers. This special issue presents recent advances in field, laboratory, and modelling studies on soil C dynamics, with a particular emphasis on those aiming to resolve abiotic and biotic influences. The manuscripts highlight three areas of investigation that we suggest are central to current and future progress in ecosystem C dynamic research: (1) novel interpretations of abiotic controls on soil CO2 efflux, (2) legacy effects of abiotic drivers of soil C dynamics, and (3) the interaction between plant C dynamics and soil biological processes

    Carbon and greenhouse gas balances in an age sequence of temperate pine plantations

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    © Author(s) 2014. This study investigated differences in the magnitude and partitioning of the carbon (C) and greenhouse gas (GHG) balances in an age sequence of four white pine (Pinus strobus L.) afforestation stands (7, 20, 35 and 70 years old as of 2009) in southern Ontario, Canada. The 4-year (2004-2008) mean annual carbon dioxide (CO2) exchanges, based on biometric and eddy covariance data, were combined with the 2-year means of static chamber measurements of methane (CH4) and nitrous oxide (N2O) fluxes (2006-2007) and dissolved organic carbon (DOC) export below 1 m soil depth (2004-2005). The total ecosystem C pool increased with age from 46 to 197 t C ha-1 across the four stands. Rates of organic matter cycling (i.e. litterfall and decomposition) were similar among the three older stands. In contrast, considerable differences related to stand age and site quality were observed in the magnitude and partitioning of individual CO2 fluxes, showing a peak in production and respiration rates in the middle-age (20-year-old) stand growing on fertile post-agricultural soil. The DOC export accounted for 10% of net ecosystem production (NEP) at the 7-year-old stand but <2% at the three older stands. The GHG balance from the combined exchanges of CO2, CH4 and N2O was 2.6, 21.6, 13.5 and 4.8 t CO2 equivalent ha-1 yearg-1 for the 7-, 20-, 35- and 70-year-old stands, respectively. The maximum annual contribution from the combined exchanges of CH4 and N2O to the GHG balance was 13 and 8% in the 7- and 70-year-old stands, respectively, but <1% in the two highly productive middle-age (20- and 35-year-old) stands. Averaged over the entire age sequence, the CO2 exchange was the main driver of the GHG balance in these forests. The cumulative CO2 sequestration over the 70 years was estimated at 129 t C and 297 t C ha-1 yearg-1 for stands growing on low- and high-productivity sites, respectively. This study highlights the importance of accounting for age and site quality effects on forest C and GHG balances. It further demonstrates a large potential for net C sequestration and climate benefits gained through afforestation of marginal agricultural and fallow lands in temperate regions

    Heat and drought impact on carbon exchange in an age-sequence of temperate pine forests

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    Background Most North American temperate forests are plantation or regrowth forests, which are actively managed. These forests are in different stages of their growth cycles and their ability to sequester atmospheric carbon is affected by extreme weather events. In this study, the impact of heat and drought events on carbon sequestration in an age-sequence (80, 45, and 17 years as of 2019) of eastern white pine (Pinus strobus L.) forests in southern Ontario, Canada was examined using eddy covariance flux measurements from 2003 to 2019. Results Over the 17-year study period, the mean annual values of net ecosystem productivity (NEP) were 180 +/- 96, 538 +/- 177 and 64 +/- 165 g C m(-2) yr(-1) in the 80-, 45- and 17-year-old stands, respectively, with the highest annual carbon sequestration rate observed in the 45-year-old stand. We found that air temperature (Ta) was the dominant control on NEP in all three different-aged stands and drought, which was a limiting factor for both gross ecosystem productivity (GEP) and ecosystems respiration (RE), had a smaller impact on NEP. However, the simultaneous occurrence of heat and drought events during the early growing seasons or over the consecutive years had a significant negative impact on annual NEP in all three forests. We observed a similar trend of NEP decline in all three stands over three consecutive years that experienced extreme weather events, with 2016 being a hot and dry, 2017 being a dry, and 2018 being a hot year. The youngest stand became a net source of carbon for all three of these years and the oldest stand became a small source of carbon for the first time in 2018 since observations started in 2003. However, in 2019, all three stands reverted to annual net carbon sinks. Conclusions Our study results indicate that the timing, frequency and concurrent or consecutive occurrence of extreme weather events may have significant implications for carbon sequestration in temperate conifer forests in Eastern North America. This study is one of few globally available to provide long-term observational data on carbon exchanges in different-aged temperate plantation forests. It highlights interannual variability in carbon fluxes and enhances our understanding of the responses of these forest ecosystems to extreme weather events. Study results will help in developing climate resilient and sustainable forestry practices to offset atmospheric greenhouse gas emissions and improving simulation of carbon exchange processes in terrestrial ecosystem models

    Hydrochemical Investigations of Lake Ecosystems of Shatsky National Park (Lake Sominetz)

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    У статті проаналізовано матеріали гідрохімічних досліджень озера Соминець. Оцінено якість води на сьогодні, з’ясовано, що вона значною мірою зумовлена антропогенними чинниками. Встановлено тенденції до підвищення мінералізації води та зміни її іонного складу. Відзначено збільшення кількості біогенів у водоймі. The paper deals with the analysis of the main hydrochemical indices of natural water of the Lake Sominetz. Water mineralization is measured on a broad scale and defined in terms of hydrochemical and hydrobiological indices. The correlation between the main components is changing, the content of biogenous substances is increasing.Роботу виконнано у відділі екологічної токсикології ІГ НАН України та науковому відділі ШН

    Hydrochemical Investigations of Lake Ecosystems of Shatsky National Park: Lake Pulemetske (1977–2009)

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    У статті проаналізовано матеріали гідрохімічних досліджень озера Пулемецьке. Дано оцінку якості води в сучасний період порівняно із ретроспективними даними. Встановлено, що якість води в озері Пулемецьке значною мірою зумовлена антропогенними чинниками. Показано тенденції до підвищення мінералізації води та зміни її іонного складу. Відмічено збільшення кількості біогенних елементів. The paper deals with the analysis of the main hydrochemical indices of natural water of the Lake Pulemetske. Water mineralization is measured on a broad scale and defined in terms of ydrochemical and hydrobiological indices. The correlation between the main components is changing, the content of biogenous substances is increasing.Роботу виконано в Інституті гідробіології НАН Україн

    Разработка бизнес-плана открытия кафе-кондитерской "SweetCake" в г. Юрга

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    В работе были проанализированы теоретические основы бизнес-планирования; выявлены преимущества малого бизнеса и рассмотрены новые льготы для его поддержки; разработан бизнес-проект предприятия общественного питания "Кафе-кондитерская "SweetCake" в г. Юрга, а так же были просчитаны мероприятия, направленные на развитие кафе-кондитерской "SweetCake".In work theoretical bases of business planning have been analyzed; the advantages of small business are revealed and new benefits for its support are considered; the business project of the public catering enterprise "Cafe-confectionery" SweetCake "in Yurga was developed, as well as the activities aimed at the development of the cafe-confectionery" SweetCake "

    Study of neuroticism and extraversion as predictors of the syndrome of emotional burnout (EBS) in students

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    The aim: To investigate internal factors – neuroticism and extroversion, which can be predictors of emotional burnout syndrome and their prevalence among student youth. Materials and methods: Used a complex of methods: theoretical – theoretical analysis, synthesis, systematization; sociological method of questioning; empirical: observation, testing-Eysenck’s methods for assessing the impact of neuroticism and externality; statistical. The object of the research is the process of influence of personal characteristics (individual factors) on the development and spread of EBS among students. Subject – personal characteristics (individual factors) of students – extraversion and neuroticism. The number of respondents was 610 students. Results: A study of the personal characteristics of neuroticism and extraversion, which can be predictors in the genesis of EBS, was conducted. It has been established that several negative internal factors influence students. The significant prevalence of internal risk factors of EBS indicates the need for a comprehensive approach to its prevention and the need for the development and application of modern adequate methods, forms, and methods of prevention. Conclusions: The presence and influence of internal factors on the development of EBS have been theoretically proven. It has been established that there is a significant propagation of personal characteristics that may have signs of negative internal factors. The need for preventive measures for the development of EBS among students has been revealed
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