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Abstract& Context Projections of species distribution models under future climate are usually based on long-term averages. However, singular extreme drought events presumably contribute to the shaping of distribution limits at the retreating low-elevation xeric limits.& Methods The objectives of this study were to set up a distribution model based on extreme drought events (EDM), which uses sanitary logging information as a proxy of vitality response of beech, and compare it with the results of classical species distribution models (SDMs).& Results Predictions of the EDM for 2025 were in agreement with those of the SDM, but EDM predicted a more serious decline in all regions of Hungary towards the end of the century.& Conclusion These results suggest that the predicted increase in frequency and severity of drought events may further limit the distribution of beech in the future.

The future use of Conservation Reserve Program (CRP) lands is an important agricultural policy issue. To examine the effects of factors that influence landowners' post-contract use of CRP lands, a survey of Texas High Plains CRP contract holders was conducted in 1992. This study analyzes the results of the survey using a qualitative choice model. It was found that the presence of a livestock enterprise in the current contract holder's operation increases the probability of these acres remaining in the established cover. Contract holders who value the commodity base have an increased probability of returning their acres to crop production.

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© iForest -Biogeosciences and Forestry IntroductionThe relationship of vegetation cover and groundwater resources has drawn considerable scientific attention over the last decades. Many studies have shown that deforestation by logging or of natural origin (forest fire, wind damage) increased the average runoff from the affected area (e.g., Bosch & Hewlett 1982) and afforestation decreased runoff. Similar results were detected in recharge rates and groundwater depth, predominantly in dry regions. In Australia changes of vegetation from woodland to grassland or crops resulted in increases in recharge rates of one to two orders of magnitude (Maitre et al. 1999). The changes were largely due to the altered interception loss and the increased water extraction from the root zone. However, results of paired watershed research agreed only on the direction of the changes, not on their magnitude (Andressian 2004).Comparative water balance studies of forest and low vegetation covers have generally shown higher water use of forest cover (Ladekarl et al. 2005, Nachabe et al. 2005, Schilling 2007. Nachabe et al. (2005) analyzed the groundwater consumption in a shallow water table environment and estimated the annual ET for a forested area (1320 mm) and for a pasture (700 mm) using detailed soil moisture and water table monitoring. At the same time, a few studies have found negligible differences in evapotranspiration of different vegetation covers (e.g., Roberts & Rosier 2005). The latter study found that, although there were seasonal differences, on an annual basis the drainage below broadleaved woodland did not significantly differ from that below a pasture.Due to climate change, air temperature is expected to rise significantly during this century (IPCC 2007). As a direct consequence of warmer temperatures, the hydrological cycle will undergo changes with accompanying alteration in the rates of precipitation and evaporation. In Hungary, summer temperatures is expected to increase by up to four degrees by the end of this century, while precipitation is likely to increase in winter and decrease in summer (Gálos et al. 2007).The impact of climate change on groundwater resources was reviewed lately by Green et al. (2011). Although the uncertainty of predictions for change in groundwater recharge rates and discharge is large (e.g., future climate scenarios and groundwater extraction), numerous studies found that groundwater resources appear to be threatened by future climate change due to increased natural and human water demand.In light of the water balance uncertainties and the increasing pressures on groundwater resources due to future climate change, a comparative water balance study of an oak forest and fallow vegetation plots was initiated in a drought-threatened lowland environment in north-eastern Hungary. Water balance components were estimated by the Hydrus 1-D numerical model (Simunek et al. 2005), calibrated on measured soil moisture and groundwater levels.Our research questions were the following: (1) what is the m...

9 Abstract Climate change can result in a slow disappearance of forests dominated by less 10 drought-tolerant native European beech (Fagus sylvatica) and oak species (Quercus spp.) 11 and further area expansion of more drought-tolerant non-native black locust (Robinia 12 pseudoacacia) against those species in Hungary. We assumed that the shift in plant species 13 composition was modified by selective ungulate browsing. Thus, we investigated which 14 woody species are selected by browsing game. We have collected data on the species 15 composition of the understory and the browsing impact on it in five different Hungarian 16 even-aged forests between 2003 and 2005. Based on these investigations the non-native 17 Robinia pseudoacacia living under more favourable climatic conditions was generally 18 preferred (Jacobs' selectivity index: D = 0.04 ± 0.77), while the native Fagus sylvatica 19 and Quercus spp. (Q. petraea, Q. robur), both more vulnerable to increasing aridity, were 20 avoided (D =-0.37 ± 0.11; -0.79 ± 0.56; -0.9 ± 0.16; respectively) among target tree 21 species. However, economically less or not relevant species, e.g. elderberry (Sambucus 22 spp.), blackberry (Rubus spp.) or common dogwood (Cornus sanguinea) were the most 23 preferred species (D = 0.01 ± 0.71; -0.12 ± 0.58; -0.2 ± 0.78, respectively). Our 24 results imply that biodiversity conservation, i.e. maintaining or establishing a multi-species 25 understory layer, can be a good solution to reduce the additional negative game impact on 26 native target tree species suffering from drought. Due to preference for Robinia pseudo-27 acacia selective browsing can decelerate the penetration of this species into native forest 28 habitats. We have to consider the herbivorous pressure of ungulates and their feeding 29 preferences in planning our future multifunctional forests in the light of climate change 30 impacts.

This paper analyses the recent recurring dieback and growth decline of Black pine (P. nigra Arn. var austriaca) in the Keszthely mountains of south-west Hungary, and their relations to water deficits due to droughts. These relations were studied in five stands with low soil water storage capacity for the period 1981-2016. The vitality was assessed using 60 tree-ring samples and changes in remotely sensed vegetation activity indices, i.e., the normalized difference vegetation index (NDVI) and the normalized difference infrared index (NDII). Water deficit was estimated by using meteorological drought indices such the standardized precipitation-evapotranspiration index (SPEI) and the forestry aridity index (FAI), as well as the relative extractable water (REW), calculated by the Brook90 hydrological model. Results revealed a strong dependency of annual tree ring width on the amount of water deficit as measured by all the above estimators, with the highest correlation shown by the summer REW. Droughts also showed a long-term superimposed effect on tree growth. NDII seemed to be more sensitive to drought conditions than NDVI. The robust dependency of tree growth on the summer water availability combined with the projected increasing aridity might lead to decreasing growth of Black pine in Hungary towards the end of the century. We thus argue that the suggestion by several papers that Black pine can be a possible substitute species in the Alpine and Mediterranean region in the future should be revisited.