*3.2. E*ff*ect of Nitrogen Fertilization on Water Concentration of Miscanthus* × *Giganteus*

The water concentration was characterized with differences between the examined parts of plants. The rhizomes, stems, and leaves were characterized by a higher water concentration at the beginning of the growing season (Table 5, Figures 5 and 6). On fertilized and unfertilized plots, the water content in the leaves (*p* = 0.0260) and stems (*p* = 0.0015) decreased until the end of the vegetation period. For rhizomes, the water content decreased until October and then increased at about 7 g in the unfertilized plot and 31 g in the fertilized plot. There was a significantly higher water concentration found in the rhizomes (*p* = 0.004) and stems (*p* = 0.0218) fertilized with nitrogen. The water concentration was significantly different during the experimental years. The highest content of water was observed in the rhizomes (*p* = 0.0000), stems (*p* = 0.0022), leaves (*p* = 0.0000), and whole aboveground parts of plants (*p* = 0.0025) in the third year of the study (Table 5). A greater water content in the aboveground part of plants was observed until November (Figure 6).


**Table 5.** Water concentration in the fresh mass of *Miscanthus* <sup>×</sup> *giganteus* (g kg<sup>−</sup>1) (average for years 2014–2016).


**Figure 5.** Water concentration in leaves and stems during the vegetation period of the years 2014–2016 (average for years).

Water concentration in leaves

**Figure 6.** Water concentration in the rhizomes and aboveground part of plants during the vegetation period of the years 2014–2016 (average for years).
