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A variety of transpiration in the young spruce stands with different thinning management
Zavadilová, Ina ; Szatniewska, Justyna ; Vágner, Lukáš ; Krejza, Jan ; Pavelka, Marian
Managing the spruce forest growing beyond its favourable conditions is trading between water consumption and increasing biomass. We examined tree transpiration in four stands with different thinning intensities in a 40-year-old spruce forest in South Moravia. Tree transpiration was significantly higher under moderate and heavy intensity compared to low intensity and control plots. Tree transpiration differed also among trees of different sizes within the treatments and also between the treatments. The stem increment was visibly increasing with the intensity of treatment, particularly for suppressed trees. The findings show an ecological tree response two years after the thinning.
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Hodnocení ekosystémových služeb veřejné sídelní zeleně
Zemek, František ; Pikl, Miroslav ; Pavelka, Marian ; Zapletal, Miloš ; Kokrda, Lukas ; Novotný, Jan ; Duchková, Helena ; Vačkářová, Davina ; Foltýnová, Lenka ; Cudlín, Pavel ; Kolařík, J. ; Holešová, H. ; Mácová, Kateřina ; Chalupová, O. ; Vojáčková, B. ; Mikulášek, J.
Metodika přináší nové praktické přístupy ke kvantifikaci pěti ekosystémových funkcí (EF) a jim odpovídajících ekosystémových služeb (ES) městské zeleně. Zahrnuje čtyři funkce regulační (teploty a mikroklimatu, záchyt CO2 a ukládání do biomasy, záchyt znečišťujících látek z ovzduší, útlum hluku z dopravy) a jednu funkci informační (estetická a kulturně rekreační). Výpočty jsou řešeny na úrovni jednotlivých prvků zeleně (strom/keř, plocha trávníku) na základě jejich skutečných dimenzí a ekofyziologických vlastností. Následné je vyjádřena jejich finanční hodnota. Pro hodnocení byly použity zjednodušené biofyzikální/statistické modely při zachování platných fyzikálních principů a s ohledem na dostupnost vhodných a existujících dat. Využívá data o městské vegetaci, které jsou standardně zajišťovány v rámci inventarizace veřejné městské zeleně samosprávami měst, a volně nebo pro obecní správu zdarma dostupné mapové podklady o městském území, meteorologických podmínkách a sociodemografické situaci.
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Odhad potenciálu sekvestrace uhlíku v České republice - Zalesňování zemědělských půd, změna lesního hospodaření, revitalizace rašelinišť a výsadby stromořadí
Hruška, Jakub ; Pavelka, Marian ; Chuman, Tomáš ; Oulehle, Filip ; Vindušková, O. ; Cudlín, Pavel ; Trnka, Miroslav
Zpráva vypočítává kvalitativně i kvantativně potenciál sekvestrace uhlíku (k roku 2050) při zalesňování zemědělských půd, změněn managementu lesů, revitalizaci mokřadů a výsadbách alejí.
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Urban ecosystem services in climate change mitigation
Štecová, I. ; Kluvánková, T. ; Pavelka, Marian
Climate change and global warming rapidly affect urban residents’ well-being. More than 72% of Europeans\nlive in urban environments, and their well-being is closely related to environmental quality. How cities are\nplanned and structured can exacerbate the negative effects of climate change even as natural elements and\ngreen areas are shrinking. The impact of high temperature on human health during heat waves will be one of\nthe most serious problems associated with climate change, and especially in large urban areas. Heat islands\nare mainly due to high concentration and large areas of impermeable surfaces, low moisture, few green areas,\nand poor ventilation. We present results from measuring heat islands at two locations in Bratislava and interview\nkey actors from three cities to identify risk perception regarding climate change. Expected results aim\nto mainstream ecosystem services into spatial planning in cities in support of operationalizing microclimatic\nfunction of green infrastructure to mitigate negative impact of climate change in cities.
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Uhlíková bilance urbánního ekosystému
Pavelka, Marian
Předmětem této zprávy je shrnutí výstupů realizovaných v rámci projektů spolupráce Ústavu výzkumu globální změny AV ČR, v. v. i. se Statutárním městem Brno a Hvězdárnou a planetáriem Brno, příspěvkovou organizací, které byly realizovány v rámci dvou ročních projektů Uhlíková bilance urbánního ekosystému 2015 a Uhlíková bilance urbánního ekosystému 2016, které byly uskutečněny v roce 2015 a v roce 2016.
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Automated eddy covariance data quality control for long-term measurements
Šigut, Ladislav ; Mauder, M. ; Sedlák, Pavel ; Pavelka, Marian ; Špunda, Vladimír
Estimation of matter and energy exchange using the eddy covariance method is often organized into regional or global networks. To achieve comparability among sites, it is important to standardize and specify the methodology used. Currently, quality control (QC) is one of the most time-demanding steps in data processing within the Czech Carbon Observation System. Although manual QC (MQC) enables consideration of more complex test applications, it is often difficult to document. The aim of this study was to establish an automated QC (AQC) scheme based on available literature and post-processing software and test its effectivity and reliability on sites comprising an agroecosystem and a mature European beech forest. AQC successfully flagged low-quality CO2 fluxes and provided estimates of net ecosystem productivity similar to estimates based on MQC. The tests’ efficiency was particularly high for the agroecosystem, where AQC removed 13% less data than did MQC. We conclude that the adopted AQC displays satisfactory performance, especially for sites with low canopy heights.
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Selection of a new site for eddy covariance research in Vietnam – Vietnamese and CzechGlobe cooperation
Nguyen, Vinh Xuan ; Pavelka, Marian ; Havránková, Kateřina ; Hoang, S.N. ; Lai, Q. T. ; Dang, S. V. ; Tran, T. V. ; Ton, M. T. ; Truong, C. Q. ; Pham, N. H. ; Tran, C. T.
A montane evergreen broadleaf forest in Bidoup-Nui Ba National Park, Vietnam was selected for a future flux study based on a set of standard selection criteria applied to five protected areas in southern Vietnam. This pristine natural ecosystem within the park is important for its biodiversity conservation, supporting high levels of plant diversity and endemism and representing the Southern Annamites montane rain forests ecoregion. This paper describes general information about the site. Common foggy and calm wind periods can pose a challenge for eddy covariance measurements. Since March 2015, measurement of the horizontal wind regime at the site has begun to provide information on local prevailing wind directions and calm periods to aid in optimizing tower positioning within the site.
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Summer fluxes of nitrous oxide from boreal forest
Macháčová, Kateřina ; Pihlatie, M. ; Halmeenmäki, E. ; Pavelka, Marian ; Dušek, Jiří ; Bäck, J. ; Urban, Otmar
Boreal forests cover almost one-third of the global forest area, and results of soil measurements show them to be a natural source of the important greenhouse gas nitrous oxide (N2O). Nevertheless, N2O fluxes from boreal tree species have been excluded from calculations of N2O exchanges from forest ecosystems. Therefore, our objective was to quantify and scale up the N2O fluxes from stems of mature silver birch (Betula pendula), Scots pine (Pinus sylvestris), and Norway spruce (Picea abies), as well as from the forest floor of a boreal forest in Finland during June and July 2014. This study shows that boreal tree species emit N2O from their stems under natural field conditions and significantly contribute up to 8% of forest floor fluxes of N2O. Spruce trees seem to be the strongest N2O emitter among the studied tree species. Moreover, the N2O flux rates from both coniferous tree species increased with decreasing soil water content. This study highlights the necessity to include N2O fluxes from trees within the total greenhouse gas budget of forest ecosystems.
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Flux footprints in different ecosystems
Macálková, Lenka ; Havránková, Kateřina ; Pavelka, Marian
Flux footprint is an upwind area where the atmospheric flux measured by an instrument is generated. Footprint size depends on measurement height, surface roughness, and atmospheric thermal stability. Our study focused on the flux footprints of four CzechGlobe ecosystem stations in a wetlands area, an agroecosystem, and young and mature spruce forests. Our aims were to prove that the sites were suitable for eddy covariance measurement and compare flux footprints under various atmospheric thermal conditions: stable, neutral, and unstable. Two computational models were used: the Kormann–Meixner (2001) and Kljun (2004)models. The outputs were processed graphically in site maps.
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Forest floor respiration of tuczno scots pine stands
Urbaniak, M. ; Pavelka, Marian ; Heronim Chojnicky, B. ; Juszczak, R. ; Dařenová, Eva ; Baran, M. ; Danielewska, A. ; Ziemblinska, K. ; Olejnik, Janusz
Tuczno forest is a 60-year-old Scots pine stand that is located in the North-West part of Poland. During the period between 20th and 25th August 2012 an experiment consisting of the measurement of forest fl oor CO2 effl ux was carried out. For this purpose, manual chamber systems were used. Measurements were taken at 60 collars located on a rectangular plot 25m x 45m. Th is research area was located in the range of footprint of the Eddy-covariance (EC) tower. Th e preliminary results indicate that the average CO2 effl ux from the forest fl oor, as measured during the experiment (5.09 μmol m-2 s-1), is lower than the total ecosystem respiration, estimated from EC data (6.25 μmol m-2 s-1). Spatial variability of soil CO2 effl ux (Rs) can be explained by humus thickness (Ht) variability; however, the tree root respiration can be considered a valuable part of CO2 emission from the forest bottom.
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