Abstract

We evaluated photosynthetic reactions in Acer campestre L. in a multi-factorial field experiment near Hodonín, Southern Moravia, Czech Republic. In this experiment, selected plots were amended with three different supplementary soil substances, that is, zeolite, lignite, and hydroabsorbent Agrisorb, and were compared with unamended control plots. Microclimatic parameters, that is, temperature, relative humidity, soil moisture, and solar radiation were measured. In the spring of 2008, supplementary soil substances were applied, and in the autumn of the same year, experimental A. campestre L. plants were harvested. The basic physiological parameters, chlorophyll content and fluorescence, stomatal conductance, and sap flow were determined in the experimental plants. Determination of the above-mentioned parameters showed higher vitality of plants cultivated on plots supplemented by lignite, followed by zeolite. In comparison with the control plants, the application of lignite led to increase of average chlorophyll content and fluorescence by 37 and 20%, respectively, stomatal conductance by 29%, and sap flow by 44% in plants. In comparison with the control plants, the application of zeolite resulted in the enhancement of average chlorophyll content and fluorescence by 14 and 15%, respectively, stomatal conductance by 16%, and sap flow by 36% in plants. The monitored parameters of plants cultivated on plots supplemented with hydroabsorbent Agrisorb were similar to those measured in control plants. In addition, the results obtained are related to actual weather. Correlations between type of the applied supplementary soil substances, soil moisture, and physiological parameters were found. Data of short-time measurement of photosynthesis response correspond with data of long-time measurement of morphological characteristics. The highest height increments were determined in experimental group cultivated under lignite application, followed by zeolite. Statistically insignificant plant height increases were observed in plants cultivated on the soil supplemented with hydroabsorbent Agrisorb.

Key words: Abiotic stress, soil conditions, microclimatic data, photosynthetic reactions, morphological characteristic, environmental sensors.