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Long-term total solar radiation variability at the Polish Baltic coast in Kołobrzeg within then period 1964-2013

Kleniewska M., Chojnicki B. H., Acosta M.

Meteorology Hydrology and Water Management. Research and Operational Applications

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2016

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Vol. 4, iss. 2

35--40

EN

This study is based on a 50-year data series (1964-2013) of total solar radiation (G) from the Kołobrzeg – station that is located on the Polish Baltic Sea coast and is characterised by a very high level of air quality. To find and remove gross errors, quality control checking procedures were applied in this study. Additionally, the homogeneity of the G series in this study has been tested on a monthly basis by using of the Standard Normal Homogeneity Test for single shifts. We found a statistically non-significant decrease in G during the period from 1964 to 2013. The decrease in the 5-year mean total solar radiation is evident from the beginning of the 1980s, with the minimum mean value occurring in the second half of the 1990s, while G slightly increased from the early 2000s. The analysis of seasonal G patterns shows that total solar radiation in summer is the most similar to the annual pattern and only the summer series trend shows a statistically significant decrease in G. We have also found two noticeable tendencies in monthly anomalies of G over the studied decades; they are negative trends in May and August. The shape of the decadal daily G histogram remained unchanged during the analysed decades.

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Sezonowy przebieg wskaźnika wykorzystania wody (WUE) w lesie sosnowym

Ziemblińska K., Urbaniak M., Danielewska A., Baran M., Juszczak R., Chojnicki B. H., Olejnik J.

Rocznik Ochrona Środowiska

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2013

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Tom 15, cz. 3

2780--2798

EN

Assessment of the ecosystem productivity in relation to the amount of water used for such kind of processes have already been investigated for the different ecosystem types by many researchers. Water Use Efficiency (WUE) parameter shows seasonal variation due to changing weather conditions, which determine processes of photosynthesis, respiration and evapotranspiration, and because of biological factors variability. The analysis of the WUE dynamics in the forest ecosystem in Tuczno research station over the hydrological year 2012 were presented in the paper. WUE was calculated based on the daily CO2 and H CO2 O fluxes measured by means of the eddy covariance system (EC) installed over the forest canopy. The fluxes were quality checked in relation to the wind direction, friction velocity values and stationary. The data series used in this investigation were not gap-filled. By using the net value of both fluxes, a good indicator which describe the behavior of the ecosystem as the whole, was obtained. Among a number of weather condition factors, that affect the value of the tested indicator (WUE), mainly photosynthetic photon flux density (PPFD) and the air temperature were evaluated. Separate analysis has been done for daily courses of both CO2 and H2 O fluxes, as well as for WUE for each month of the analyzed period. The highest values of H2 O fluxes (FH) were observed in May and June (0.25 and 0.3 kg m-2s-1) and the lowest in the period from September to December (0.02–0.05 kg m-2s-1). The daily courses of water vapor fluxes revealed dependence to the measured PPFD fluxes, which determines in turn the intensity of the evapotranspiration process. The time courses of the daily 30-min average carbon dioxide fluxes (FC) were also highly variable in each month, similarly to the variances of the FH fluxes. The lowest values of the net F COC were measured in the period from October to December (net CO2 fluxes did not exceed 0.55g m-2 s-1), while in the period from April to July the net ecosystem productivity was the biggest (1.5–2.0 m-2s-1),). WUE reached its minimum in May (7 g [CO2] kg-1), [H2O]), what indicates that the evapotranspiration of the ecosystem was the least effective from the point of view of COCOD absorption from the atmosphere (the ecosystem had a high productivity but it lost a great amount of water at the same time). In contrary, higher WUE values were observed in the colder period of the year, when the amount of available radiant energy was limited. WUE reached its peak in September (nearly 45 g of [CO2] kg-1), [H2O] ) which reveals, that in autumn the decline of evapotranspiration rates were higher than rates of the net CO2 exchange decrease. It also highlights the high adaptability of Scots pine (main species in studied forest ecosystem – 99%), to described conditions. The designated water use efficiency (WUE) parameter, may be used as a good indicator of the current condition of the ecosystem.

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Próba oceny produktywności ekosystemu w warunkach polowych Wielkopolski

Kowalska N., Chojnicki B. H., Józefczyk D., Urbaniak M., Juszczak R., Olejnik J.

Rocznik Ochrona Środowiska

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2013

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Tom 15, cz. 3

2481--2495

EN

The Eddy Covariance technique has been applied for corn field NEE estimation. The Smith, Michaelis-Menten and Misterlich formulas has been used for calculation of net ecosystem exchange (NEE) values between corn canopy and the atmosphere. These approaches have been applied for estimation of temeparture and radiation modification impact on the corn field productivity. The NEE has been evaluated in the first part of this paper and then the relation of NEE runs and elements that influence the NEE values has been summarized. In another part the analysis of NEE under thermal and radiative conditions has been presented. The Michaelis-Menten model has been found as the most distinct one for the measurements of the relationship. This model indicated that the highest NEE value (NEE = 10.0 µmol m-2 s-1) has been found under combination of the low radiation and high temperature conditions. The lowest value of NEE has been estimated under the highest PPFD and lowest Ta amount. The applied models have confirmed relationship between NEE, PPFD and Ta. All three models confirmed the fact that the lowest ecosystem productivity is found under high radiation input. The accumulated NEE values were compared with the real values according to the Smith, Michaelis-Menten and Misterlich equations. The results of the Michaelis-Menten equation and Misterlich were the most similar to the real cumulative NEE values. The theoretical change of thermal (0.5°C increase) and radiation (4% decrease) resulted in tested higher CO2 sequesteration from the atmosphere.

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Nowoczesne metody pomiaru wymiany masy i energii pomiędzy podłożem a atmosferą

Chojnicki B. H., Urbaniak M., Leśny J., Juszczak R., Olejnik J.

Przegląd Naukowy Inżynieria i Kształtowanie Środowiska

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2008

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Vol. 17, No. 1

91--97

EN

The heat and mass exchange measurement techniques are commonly used for environmental studies. Globally we observe rapid increase of greenhouse gases concentration in the atmosphere. This phenomenon causes stronger interest in gas exchange measuring techniques such as eddy covariance, eddy accumulation and chambers. These techniques has been recently developed at Agromeotorology Department for water vapor, carbon dioxide, methane and nitrous dioxide exchange measurements. The measurements of CO2, CH4, N2O and heat fluxes using described above techniques has been carried out at Rzecin wetland since the beginning of 2004. These activities have been realized in the framework of European integrated projects both CARBOEUROPE and NITROEUROPE.