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Agroforestry systems do not belong to a common agricultural practice in the Czech Republic. Th ese approaches are, however, seen as potentially benefi cial in terms of sustainable use of landscape resources. At experimental submontane site with woody-species strips and extensivelymanaged meadow intercropping, production characteristics of hay harvested from the meadows and impacts of the strips on microclimate were studied. Microclimatic conditions were monitored using a set of meteorological stations. Th e site characteristics such as soil moisture and temperature, air temperature and precipitation were measured in transect C. Th e meadows were experimentally cut twice a year (June 1st cut, September 2nd cut), and herbal species were determined in the sampling points of transects. Impacts of the woody-species strips on the crop properties such as water content and its dry weight were found. Th e strips aff ected the soil temperature and the moisture compared to the openarea conditions and the strips also reduced precipitation. Moreover, reduced numbers of herbal species were found in the vicinity of the strips. [ABSTRACT FROM AUTHOR]

From November 2018 until January 2019, the frost resistance of white oak (Quercus petraea (Matt.) Liebl.), European beech (Fagus sylvatica L.), Scots pine (Pinus sylvestris L.), Norway spruce (Picea abies (L.) Karst.) and Douglas fir (Pseudotsuga menziesii (Mirb.) Franco) plantig stock was evaluated. After exposing the shoots to frost, the tissue damage was assessed by measuring: the ratio of electrical resistance before and after freezing (R1 /R2 ), the relative electrical conductivity of shoots leakage, and the occurrence of color changes in different tissues and chlorophyll fluorescence of the needles. The method of evaluating tissue color changes is reliable, but it takes long time to decide on the storability of plantig stock. From the faster methods, chlorophyll fluorescence measurement proved to be the most suitable for conifers. For the deciduous trees, it is suitable to measure the relative electrical conductivity of shoots leakage. [ABSTRACT FROM AUTHOR]

The goal of this study is evaluation of the effect of different levels of plant water stress on their subsequent performance in the first growing season after planting. The most noticeable manifestation of current global climate change are more frequent drought periods of greater intensity and different duration. For successful artificial forest restoration, the basic factor is the use of high-quality planting stock showing both morphological quality and desired physiological status. The physiological status of the plants is one of the most important factors predisposing survival rates and growth after planting. For objective evaluation of their water regime a water potential (stress) of plants was measured using the pressure chamber, water content, water deficit and relative electrical conductivity. For the reforestation of large clear cuts, which area is increasing currently, it is necessary to use also artificial renewal using preparatory (pioneer) trees. The results showed that all the methods used to evaluate the physiological quality responded to the stress of silver birch and European aspen seedlings exposed to deliberate drying and corresponded to losses and reduced growth after planting. The birch seedlings were more sensitive to drying when compared to aspen. [ABSTRACT FROM AUTHOR]

In order to determine the possible disturbance of the planting material by incorrect manipulation, the method of plant moisture stress (PMS) assessment was used. Two-year-old Scots pine (Pinus sylvestris L) seedlings collected on two different dates in two forest nurseries were used. Seedlings were exposed to controlled drying - loosely distributed on the shelves in the laboratory with exposed roots for 2, 4 and 6 hours. For fresh and exposed seedlings the plant water stress PMS was measured by the pressure chamber and the water content in the above-ground parts and roots gravimetrically as the differences between fresh weight and dry matter. Other seedlings of the same treatments were planted in outdoor conditions. Naked roots lost water 2 to 3 times faster than shoots. During drying significantly increased water stress PMS (3-7 bars in unexposed, more than 13 bars aft er 2 hours and 18.5 to nearly 30 bars aft er 4 and 6 hours of exposure). PMS significantly correlated with water content in roots and shoots. The high PMS values also corresponded to high mortality (no loss in unexposed seedlings, 25-55% aft er 2 hours and more than 80% aft er 4 and 6 hours of drying). [ABSTRACT FROM AUTHOR]

The work evaluates the impact of simulated late frost and subsequent exposure to different irradiation on damage of the assimilation apparatus of fir (Abies alba Mill.) seedlings grown in different light conditions. Seedlings grown in shaded bed or in full sun were exposed for 5 hours to freezing temperatures with minimum temperature of -4.5 °C in a growth chamber. Subsequently, one part of seedlings was exposed to light intensity of cca 15,000 lux, and the other to 500 lux during 16 hours of simulated day (17 °C). Prior and after the application of frost, and then at weekly intervals chlorophyll fluorescence of one-year-old needles was measured. Analyzed parameters were as follows: maximum quantum yield of chlorophyll fluorescence (Fv/Fm), performance index on absorption basis (PIabs), absorptivity (Abs) and electron transport rate (ETR). Flushing seedlings were more susceptible to frost damage than seedlings that did not begin to flush yet. Unlike the flushing shoots, the frost damage of one-year-old needles was reversible, and their assimilation apparatus regenerated during 1-2 weeks. Assimilation apparatus of the seedlings exposed after frost to weak radiation was damaged significantly less than that of seedlings exposed to full light. [ABSTRACT FROM AUTHOR]