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Start Over Creator Balogh, J.

1. Anatomical and eco-physiological changes in leaves of couch-grass (Elymus repens L.), a temperate loess grassland species, after 7 years growth under elevated CO2 concentration

Creator:
Engloner, A. I., Kovács, D., Balogh, J., and Tuba, Z.
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
mesophyll, net photosynthetic rate, phloem, sclerenchyma, stomatal conductance, stomatal density, tracheary, transpiration rate, and water use efficiency
Language:
Multiple languages
Description:
Leaf anatomy and eco-physiology of Elymus repens, a temperate loess grassland species, were determined after seven years of exposure to 700 μmol (CO2) mol-1 (EC). EC treatment resulted in significant reduction of stomatal density on both surfaces of couch-grass leaves. Thickness of leaves and that of the sclerenchyma tissues between the vessels and the adaxial surfaces, the area of vascular bundle, and the volumes of phloem and tracheary increased at EC while abaxial epidermis and the sclerenchyma layer between the vessel and the abaxial surface were thicker at ambient CO2 concentration (AC). Stomatal conductance and transpiration rates were lower in EC, while net CO2 assimilation rate considerably increased at EC exposure. Contents of soluble sugars and starch were higher in EC-treated couch-grass leaves than in plants grown at AC. and A. I. Engloner ... [et al.].
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

2. Chamber series and space-scale analysis of CO2 gas-exchange in grassland vegetation: A novel approach

Creator:
Czóbel, Sz., Fóti , Sz., Balogh, J., Nagy, Z., Bartha, S., and Tuba, Z.
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
canopy chamber, grassland, loess, sand, and stand CO2 measurements
Language:
Multiple languages
Description:
Significant part of our work was developing a new type of CO2 and H2O gas exchange chambers fit for measuring stand patches. Ground areas of six chambers (ranged between 0.044-4.531 m2) constituted a logarithmic series with doubling diameters from 7.5 to 240.0 cm. We demonstrate one of the first results for stand net ecosystem CO2 exchange (NEE) rates and temporal variability for two characteristic Central European grassland types: loess and sand. The measured mean NEE rates and their ranges in these grasslands were similar to values reported in other studies on temperate grasslands. We also dealt with the spatial scale dependence from ecophysiological point of view. Our chamber-series measurement was performed in a perennial ruderal weed association. The variability of CO2-assimilation of this weed vegetation showed clear spatial scale-dependence. We found the lowest variability of the vegetation photosynthesis at the small-middle scales. The results of spatial variability suggest the 0.2832 m2 patch size is the characteristic unit of the investigated weed association and there is a kind of synphysiological minimi-area with characteristic size for each vegetation type. and Sz. Czóbel ... [et al.].
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

3. Comparison of CO2 and H2O fluxes over grassland vegetations measured by the eddy-covariance technique and by open system chamber

Creator:
Balogh, J., Nagy, Z., Fóti, Sz., Pintér, K., Czóbel, Sz., Péli, E. R., Acosta, M., Marek, M. V., Csintalan, Zs., and Tuba, Z.
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
leaf area index
Language:
Multiple languages
Description:
Measurements of CO2 and H2O fluxes were carried out using two different techniques-eddy-covariance (EC) and open system gas exchange chamber (OC)-during two-years' period (2003-2004) at three different grassland sites. OC measurements were made during fourteen measurement campaigns. We found good agreement between the OC and EC CO2 flux values (n = 63, r 2 = 0.5323, OC FCO2 = -0.6408+0.9508 EC FCO2). The OC FH2O values were consistently lower than those measured by the EC technique, probably caused by the air stream difference inside and outside the chamber. Adjusting flow rate within the chamber to the natural conditions would be necessary in future OC measurements. In comparison with EC, the OC proved to be a good tool for gas exchange measurements in grassland ecosystems. and J. Balogh ... [et al.].
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

4. Seasonal CO2-exchange variations of temperate semi-desert grassland in Hungary

Creator:
Balogh, J., Fóti, Sz., Juhász, A., Czóbel, Sz., Nagy, Z., and Tuba, Z.
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
chamber technique, net ecosystem CO2 exchange, soil respiration, and soil water content
Language:
Multiple languages
Description:
CO2 exchange components of a temperate semi-desert sand grassland ecosystem in Hungary were measured 21 times in 2000-2001 using a closed IRGA system. Stand CO2 uptake and release, soil respiration rate (Rs), and micrometeorological values were determined with two types of closed system chambers to investigate the daily courses of gas exchange. The maximum CO2 uptake and release were -3.240 and 1.903 μmol m-2 s-1, respectively, indicating a relatively low carbon sequestration potential. The maximum and the minimum Rs were 1.470 and 0.226 μmol(CO2) m-2 s-1, respectively. Water shortage was probably more effective in decreasing photosynthetic rates than Rs, indicating water supply as the primary driving variable for the sink-source relations in this ecosystem type. and J. Balogh ... [et al.].
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public