This study aims to investigate the precipitation trends in Keszthely (Western Hungary, Central Europe) through an examination of historical climate data covering the past almost one and a half centuries. Pettitt’s test for homogeneity was employed to detect change points in the time series of monthly, seasonal and annual precipitation records. Change points and monotonic trends were analysed separately in annual, seasonal and monthly time series of precipitation. While no break points could be detected in the annual precipitation series, a significant decreasing trend of 0.2–0.7 mm/year was highlighted statistically using the autocorrelated Mann-Kendall trend test. Significant change points were found in those time series in which significant tendencies had been detected in previous studies. These points fell in spring and winter for the seasonal series, and October for the monthly series. The question therefore arises of whether these trends are the result of a shift in the mean. The downward and upward shift in the mean in the case of spring and winter seasonal amounts, respectively, leads to a suspicion that changes in precipitation are also in progress in these seasons. The study concludes that homogeneity tests are of great importance in such analyses, because they may help to avoid false trend detections.

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Abstract⎯ Parametric methods (linear trend, t-test for slope) for analyzing time series are the simplest methods to get insight to the changes in a variable over time. These methods have a requirement for normal distribution of the population that can be a limit for application. Non-parametric methods are distribution-free methods, and investigators can have a more sophisticated view to the variable tendencies in time series. 144-year-long time series of precipitation data measured at the meteorological station in Keszthely, Hungary (latitude: 46°44′, longitude: 17°14′, elevation: 124 m above Baltic sea level) were analyzed by Mann-Kendall trend test for detecting tendencies in the time series. Sen's slope estimator was applied to estimate the slope of the linear changes. In average, 44 mm decline can be shown for 100 years in the annual sum, 29.7 mm and 25.7 mm in the precipitation sum of spring and autumn (in 100 years), respectively. The rainfall sum of winter increased by 15.4 mm. Sums of April, May, and October declined by 10.8 mm, 13 mm, and 20.9 mm, respectively, according to one-tailed Mann-Kendall tests. These results were compared to the previous results of the authors carried out by parametric methods. Results of two-tailed tests of parametric and non-parametric methods are easily comparable. Parametric method (linear trend) proved significant decreasing tendencies for spring, April, and October. Nonparametric Mann-Kendall tests show significant declining tendencies for spring, autumn, and October.

The aim of the present study is to extend the applicability of MRI measurements similar to those used in human diagnostics to the examination of water barriers in living plants, thus broadening their use in natural sciences. The cucumber, Cucumis sativus, and Phillyrea angustifolia, or false olive, were chosen as test plants. The MRI measurements were carried out on three samples of each plant in the same position visa -vis the MRI apparatus using a Siemens Avanto MRI scanner. Two different relaxation times were employed, T 1 , capable of histological mapping, and T 2 , used for the examination of water content. In the course of the analysis, it was found that certain histological formations and branching cause modifications to the intensity detected with relaxation time T 2. Furthermore, these positions can also be found in T 1 measurements. A monotonic correlation (cucumber: ρ = 0.829; false olive: ρ =-0.84) was observed between the T 1 and T 2 measurements. In the course of the statistical analysis of the signal intensities of the xylems it was concluded that they cannot be regarded as independent in a statistical sense; these changes rather depend on the anatomic structure of the plant, as the intensity profile is modified by nodes, leaves and branches. This serves as a demonstration of the applicability of MRI to the measurement of well know plant physiological processes. The special parametrization required for this equipment, which is usually used in human diagnostics, is also documented in the present study.

A globális klímaváltozás egyik oka az üvegházhatású gázok antropogén kibocsátása, amelyhez többek között a turizmus is hozzájárul. A tanulmány paraméteres és nemparaméteres eljárások segítségével elemzi az üvegházhatásúgáz-kibocsátás 1985 és 2017 közötti alakulását az I nemzetgazdasági ágban (szálláshely-szolgáltatás és vendéglátás). A szerzők a vizsgált üvegházhatású gázok összessége és ezen belül a fluorozott szénhidrogének, valamint a perfluorkarbon kibocsátása esetében igazolnak szignifikáns tendenciát. Azt is tanulmányozzák, hogy az 1995–2017-es időszakban milyen kapcsolat állt fenn az ág bruttó hozzáadott értéke és üvegházhatásúgáz-kibocsátása között a gázokat együtt és külön is tekintve. Eredményeik szerint az előbbiek vonatkozásában nincs szignifikáns kapcsolat, egyes gázok esetén viszont van. A turizmus (I) nemzetgazdasági ág hozzájárulása az ország gazdasági teljesítményéhez 1995 és 2017 között összegszerűleg szignifikánsan növekedett, de aránya a bruttó hozzáadott értékből 2017-ben csupán 1,86 százalékot tett ki. A nemzetgazdasági ág karbonhatékonyságában évente átlagosan 5,8 százalékos javulás volt megfigyelhető.