The goal of this contribution is to assess the impacts of a global climate change on the Bilina basin hydrological regime. First part of the contribution focussed on the assessment of hydrological changes in the catchment and evaluation of flow conditions for the coal pit flooding. The Bilina basin is located in the northern Bohemia region near the Krusne Hory Mts. All the territory is intensively used as a coal mine area. Primarily eight climatic scenarios were selected on the basis of GCM ECHAM4 and HadCM2 to generate affected meteorological conditions. New data series were created - temperatures and precipitation – as the input for a rainfall-runoff model. The SACRAMENTO SAC-SMA model has been chosen as a tool for the rainfall-runoff simulations. A number of problems caused by the heavy influence of human activities appeared during a calibration. The model has been successfully verified and eight affected flow data series have been simulated. The scenarios have been ordered according to their influence on hydrological regime. The simulated flows have been statistically analysed and compared. The results show that significant shift in flow annual distribution could be expected. and Příspěvek se zabývá posouzením dopadu globální změny klimatu na hydrologický režim povodí Bíliny a zatápění zbytkové jámy Bílina. První část článku se zaměřuje na posouzení hydrologických změn povodí Bíliny a stanovení průtokových poměrů pro vlastní řešení zatápění zbytkové jámy za klimatické změny. Povodí je součástí Severočeské hnědouhelné pánve. Pro simulaci ovlivněných klimatických podmínek bylo zvoleno osm klimatických scénářů vytvořených na základě výstupů ze dvou globálních cirkulačních modelů ECHAM4 a HadCM2. Byly generovány nové srážkové a teplotní řady sloužící jako vstupy pro srážkoodtokový model SACRAMENTO SAC-SMA, který byl vybrán pro modelování ovlivněných průtoků. V průběhu kalibrace modelu se objevily nesrovnalosti způsobené silným antropogenním ovlivněním povodí; přesto se model podařilo úspěšně verifikovat a pro všech osm zvolených scénářů simulovat ovlivněné průtokové řady. Dané klimatické scénáře a simulované průtoky jsme podle míry ovlivnění hydrologického cyklu ohodnotili a vzájemně porovnali. Výsledky ukázaly, že je možné očekávat výrazný posun v rozložení dlouhodobých měsíčních odtoků.
The goal of this contribution is to assess the impacts of global climate change on the Bilina basin hydrological regime and the Bilina mine filling. The second part is focussed on flooding of the coal pit under the conditions affected by global warming. There are two approaches how to achieve the objective. The first method uses water from the Bilina river exclusively. The second one takes into consideration an advantage of the existing water resource system and of large water framework enabling water transfer from the Ohre river to the Bilina river to derive portion of water from the Ohre river. The operating regulations at the Nechranice reservoir had to be adapted to the climate change to improve controlled increase of discharge with regard to the flows transported. A simple water balance model was constructed to simulate a function of the Nechranice reservoir and the coal pit filling. Estimation of the climate change influence on the coal pit filling was performed based on the flooding time changes. The results of flooding simulation show that it is not possible to achieve the coal pit flooding by the Bilina river and it is necessary to transfer water from Ohre river to Bilina river. The climate change could significantly prolong the flooding of the coal pit by about 3 years and the operating regulations at the Nechranice reservoir could be considerably influenced. The impact of climate change could be substantially reduced by an improvement of the controlled increase of discharge by the Nechranice reservoir. and Příspěvek se zabývá posouzením dopadu globální změny klimatu na hydrologický režim povodí Bíliny a zatápění zbytkové jámy Bílina. Druhá část článku se zaměřuje na vlastní zatápění zbytkové jámy za klimatické změny. Vytěžená jáma povrchového lomu může být zatopena dvěma způsoby. První způsob využívá k zatopení jámy pouze vodu z řeky Bíliny, druhý počítá s převáděním vody z řeky Ohře do Bíliny pomocí existující vodohospodářské soustavy. Vzhledem ke změněným hydrologickým podmínkám bylo nezbytné přizpůsobit manipulace na nádrži Nechranice na řece Ohři klimatické změně tak, aby bylo možné zabezpečit požadovaný nadlepšený odtok v odběrném profilu čerpací stanice ke krytí požadavků na velikost plnicího přítoku zbytkové jámy Bílina. K tomuto účelu byl vytvořen jednoduchý bilanční model funkce nádrže Nechranice zohledňující různé velikosti převáděných objemů vody. Posouzení vlivu klimatické změny na zatápění zbytkové jámy proběhlo na základě rozboru délky plnění jámy. Simulace plnění zbytkové jámy ukázaly, že jámu nelze zatopit v doporučené době a bude proto nezbytné realizovat převody vody z Ohře do Bíliny. Klimatická změna patrně podstatně prodlouží dobu zatápění jámy zhruba o 3 roky a také výrazně zasáhne do manipulací na nádrži Nechranice. Nádrž Nechranice může podstatně zmírnit dopad klimatické změny úpravami velikostí nadlepšených odtoků.
Lake Śniardwy is the largest among more than 7000 Polish lakes. So far, it has not been a subject of detailed investigations concerning long-term changes in water temperature or ice regime. A considerable change in thermal and ice conditions has been observed in the period 1972–2019. Mean annual water temperature increased by 0.44°C dec–1 on average, and was higher than an increase in air temperature (0.33°C dec–1). In the monthly cycle, the most dynamic changes occurred in April (0.77°C dec–1). In the case of ice cover, it appeared increasingly later (5.3 days dec–1), and disappeared earlier (3.0 days dec–1). The thickness of ice cover also decreased (2.4 cm dec–1). Statistical analysis by means of a Pettitt test showed that the critical moment for the transformations of the thermal and ice regime was the end of the 1980’s. In addition to the obvious relations with air temperature for both characteristics, it was evidenced that the occurrence of ice cover depended on wind speed and snow cover. The recorded changes in the case of Lake Śniardwy are considered unfavourable, and their consequences will affect the course of physical, chemical, and biological processes in the largest lake in Poland.
In many Austrian catchments in recent decades an increase in the mean annual air temperature and precipitation has been observed, but only a small change in the mean annual runoff. The main objective of this paper is (1) to analyze alterations in the performance of a conceptual hydrological model when applied in changing climate conditions and (2) to assess the factors and model parameters that control these changes. A conceptual rainfall-runoff model (the TUW model) was calibrated and validated in 213 Austrian basins from 1981–2010. The changes in the runoff model’s efficiency have been compared with changes in the mean annual precipitation and air temperature and stratified for basins with dominant snowmelt and soil moisture processes. The results indicate that while the model’s efficiency in the calibration period has not changed over the decades, the values of the model’s parameters and hence the model’s performance (i.e., the volume error and the runoff model’s efficiency) in the validation period have changed. The changes in the model’s performance are greater in basins with a dominant soil moisture regime. For these basins, the average volume error which was not used in calibration has increased from 0% (in the calibration periods 1981–1990 or 2001–2010) to 9% (validation period 2001–2010) or –8% (validation period 1981–1990), respectively. In the snow-dominated basins, the model tends to slightly underestimate runoff volumes during its calibration (average volume error = –4%), but the changes in the validation periods are very small (i.e., the changes in the volume error are typically less than 1–2%). The model calibrated in a colder decade (e.g., 1981–1990) tends to overestimate the runoff in a warmer and wetter decade (e.g., 2001–2010), particularly in flatland basins. The opposite case (i.e., the use of parameters calibrated in a warmer decade for a colder, drier decade) indicates a tendency to underestimate runoff. A multidimensional analysis by regression trees showed that the change in the simulated runoff volume is clearly related to the change in precipitation, but the relationship is not linear in flatland basins. The main controlling factor of changes in simulated runoff volumes is the magnitude of the change in precipitation for both groups of basins. For basins with a dominant snowmelt runoff regime, the controlling factors are also the wetness of the basins and the mean annual precipitation. For basins with a soil moisture regime, landcover (forest) plays an important role.
Metabolite changes and senescence behaviour after mechanical phloem girdling were studied in leaf tissue of Quercus pubescens. Sugar accumulation is not only considered to be an important part of several developmental signalling pathways, but is also seen as one of the basic triggers for senescence induction, or at least an obligatory accessory phenomenon. Our survey showed that an accumulation of the soluble sugars, glucose and fructose, was not on its own obligatorily connected with the induction of leaf senescence, since no indication or even an onset of senescence could be observed during the course of the experiment. Instead, we observed an inhibition of leaf development with a decrease of photosynthesis and a slow-down of development in nearly all chlorophyll a fluorescence analysis parameters using the JIP-test. We detected a change of metabolites linked to oxidative stress, possibly due to an overexcitation of the developmentally inhibited photosynthetic apparatus., V. Holland, L. Fragner, T. Jungcurt, W. Weckwerth, W. Brüggemann., and Obsahuje bibliografii
The climatic variability and climate changes in the geological history of Earth are correlated with the environmental development. A special attention is paid to the impact of changing climate on the water resources and hydrological cycle. Possible impact of man's activities on the climatic variability is also discussed. Can the regulation of such activities slow down or bring to a stop the forthcoming climate change? A comparison of data from the Holocene period and from modern history indicates that the climatic variability and climate change have been always produced by external periodic phenomena and occasional cataclysmic events. In other words, the climate has never been stable and administrative measures limiting man's influence on the climate can bring only partial results. Considering that the climatic change is an unavoidable process, following measures should be taken: First, alternative scenarios of possible climatic development, would it be cooling or warming, should be set up. Second, preventive and protective methodologies need to be prepared for each scenario well in advance. Third, technologies facilitating man's survival and everyday life under changed climatic situation should be developed. and Klimatická variabilita a změny klimatu jsou sledovány v geologické historii Země a korelovány s historií životního prostředí. Zvláštní pozornost se věnuje vlivu měnícího se klimatu na vodní zdroje a hydrologický cyklus. Také je diskutován vliv činnosti člověka ve vztahu ke klimatu. Je možné redukcí takových aktivit zpomalit nebo zcela zastavit klimatické změny? Porovnání dat z holocénu a moderní historie ukazuje, že klimatická variabilita a změny byly vždycky vyvolávány mimozemskými periodickými vlivy, případně občasnými katastrofickými jevy. Jinými slovy, klima nikdy nebylo stabilní. Proto také administrativní opatření, omezující vliv člověka na klima, mohou být úspěšná pouze do jisté míry. Uvážíme-li, že klimatická variabilita i její hydrologické následky jsou nevyhnutelné, je třeba připravit příslušné scénáře možných klimatických změn, ať už souvisí s ochlazováním nebo oteplováním. Pro každý ze scénářů je třeba navrhnout metody preventivních a ochranných opatření s dostatečným předstihem. Konečně bude třeba vypracovat nové technologie usnadňující život člověka ve změněných klimatických podmínkách.
The paper introduces the Special Section on the Hydrology of the Carpathians in this issue. It is the result of an initiative of the Department of Land and Water Resources Management of the Slovak University of Technology in Bratislava, the Institute of Hydraulic Engineering and Water Resources Management of the TU Vienna and the Institute of Geomatics and Civil Engineering of the University of Sopron to allow young hydrologists in the Carpathian Basin (and from outside) to present their research and re-network on the emerging topics of the hydrology of the Carpathians at the HydroCarpath Conferences since 2012.
The number of species of migratory Lepidoptera (moths and butterflies) reported each year at a site in the south of the UK has been rising steadily. This number is very strongly linked to rising temperatures in SW Europe. It is anticipated that further climate warming within Europe will increase the numbers of migratory Lepidoptera reaching the UK and the consequences of this invasion need urgent attention.
Anthropogenic activities are changing global precipitation regimes and result in many middle latitude arid and semiarid regions experiencing less precipitation and more extreme weather events. However, little is known about the response of active ingredient accumulation in the medicinal herb Plantago depressa Willd. Therefore, we carried out a greenhouse experiment in order to study effect of control (CK, normal water supply equal to 309 mm per four months), -30 (-WS) and +30% (+WS) of the control water supply on the photosynthesis (PN), C/N ratio, and plantamajoside accumulation in P. depressa. Our results showed that compared with the-WS and CK treatments, the +WS treatment significantly enhanced biomass, the C/N ratio, plantamajoside concentration, yield in shoots and roots, and PN, but declined the N concentration in shoots and roots. The plantamajoside concentration was positively correlated with PN, the soluble sugar content, and the C/N ratio, but negatively correlated with the N concentration. Our results suggested that, under experimental conditions, +WS increased the C/N ratio and promoted the plantamajoside accumulation of P. depressa., Z. Li, W. Bai, L. Zhang, L. Li., and Obsahuje bibliografii
This work aimed to evaluate if gas exchange and PSII photochemical activity in maize are affected by different irradiance levels during short-term exposure to elevated CO2. For this purpose gas exchange and chlorophyll a fluorescence were measured on maize plants grown at ambient CO2 concentration (control CO2) and exposed for 4 h to short-term treatments at 800 μmol(CO2) mol-1 (high CO2) at a photosynthetic photon flux density (PPFD) of either 1,000 μmol m-2 s-1 (control light) or 1,900 μmol m-2 s-1 (high light). At control light, high-CO2 leaves showed a significant decrease of net photosynthetic rate (PN) and a rise in the ratio of intercellular to ambient CO2 concentration (Ci/Ca) and water-use efficiency (WUE) compared to control CO2 leaves. No difference between CO2 concentrations for PSII effective photochemistry (ΦPSII), photochemical quenching (qp) and nonphotochemical quenching (NPQ) was detected. Under high light, high-CO2 leaves did not differ in PN, Ci/Ca, ΦPSII and NPQ, but showed an increase of WUE. These results suggest that at control light photosynthetic apparatus is negatively affected by high CO2 concentration in terms of carbon gain by limitations in photosynthetic dark reaction rather than in photochemistry. At high light, the elevated CO2 concentration did not promote an increase of photosynthesis and photochemistry but only an improvement of water balance due to increased WUE. and C. Arena, L. Vitale, A. Virzo de Santo.