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Aims: More intense and frequent droughts predicted for the future will heavily affect grasslands worldwide and, along with various other disturbances, possibly trigger major vegetation shifts. Therefore, documenting these changes and understanding the mechanisms behind them is essential. Our study aimed to investigate how dominant species in a semiarid grassland respond to a combination of small‐scale experimental disturbances and naturally occurring droughts and uncover the underlying mechanisms. Location: Central Hungary. Methods: We conducted a small‐scale disturbance experiment in a semiarid temperate grassland and followed recovery for 18 years, including severe drought events. In 1999, we established 16 sites, eight dominated by Festuca vaginata and another eight by Stipa borysthenica, the two dominant species of sand grasslands in the region. At each site, three permanent plots were marked that received either a cutting or digging treatment or remained as controls. We monitored the cover and density changes of Festuca and Stipa annually. Results: In the early years following the disturbance, Festuca recovered at a similar rate under both disturbance treatments, while Stipa recovered faster in cut than in dug plots. When natural drought events caused major diebacks of both species, Stipa recovered very quickly and regained dominance in initially Stipa‐dominated plots, and it also took over in initially Festuca‐dominated control and cut plots. However, digging at Festuca‐dominated sites delayed drought‐induced Stipa colonisation and thus favoured Festuca recovery. We found that the poor performance of Stipa in dug plots was related to sharply reduced seedling establishment, which resulted from the low number of seeds captured by the bare soil surface after digging. Conclusions: Our results demonstrate that recurring drought events may induce dominance shifts in temperate grasslands, but small‐scale disturbances can modulate vegetation responses. Our findings emphasise the importance of post‐disturbance regeneration patterns in drought‐induced vegetation shifts and show that seed dispersal strategy may have a major effect on vegetation dynamics. [ABSTRACT FROM AUTHOR]

The aim of our research was to adapt Chuine's unified model to estimate the beginning of blooming of three apricot cultivars ('Ceglédi bíborkajszi', 'Gönci magyar kajszi', and 'Rózsakajszi C.1406') in Hungary in the time period 1994–2020. The unified model is based on the collection of chilling and forcing units. The complexity of the model lies in the high number of parameters necessary to run it. Following the work of other researchers, we reduced the number of relevant model parameters (MP) to six. In order to estimate the six MPs, we used a simulated annealing optimization method (known for being effective in avoiding getting stuck in local minima). From the results, we determined the local optimum of six MPs, and the global optimum parameter vector for three apricot cultivars. With these global optimum parameter vectors, the beginning of blooming could be estimated with a root-mean-square error (RMSE) of less than 2.5 days, using the knowledge of the daily mean temperature in the time period 1994–2020. [ABSTRACT FROM AUTHOR]