Kovářová Markéta, Pyszko Petr, Plášek Vítězslav
Department of Biology and Ecology, Faculty of Science, University of Ostrava, Chittussiho 10, 71000 Ostrava, Czech Republic.
Institute of Biology, University of Opole, 45-040 Opole, Poland.
Plants (Basel). 2021 Dec 25;11(1):63. doi: 10.3390/plants11010063.
The pH of tree bark is affected by many factors, amongst them epiphytic bryophytes changing in their active state environment. Thus, we hypothesized that bryophytes can change bark acidity, dependently of the inclination of the branches, as inclination affect the water regime and particle deposition. We measured the pH under bryophyte cushions and compared it to nearby naked bark. Additionally, we compared results with experimental bark covering with neutral cover. We found that the pH of naked bark declines with decreasing inclination of trunks. Although bryophyte cover did not generally change the pH of the bark, there was a significant interaction with inclination: with higher inclination, bryophytes decrease the pH reaction of bark, while with lower inclination they increase it. One possible explanation may lie in changes to alkaline particle deposition, or conversely in the acidification of the bark by leaching. In addition, an experiment with a neutral cover showed that naked bark covering would substantially increase pH. As, on average, bryophytes do not change the pH of bark, there can be mutual interference between the alkalizing effect of the bark cover itself and the acidifying biological effect of bryophytes.
树皮的pH值受多种因素影响，其中包括附生苔藓植物在其活跃状态环境中的变化。因此，我们推测苔藓植物可以改变树皮酸度，这取决于树枝的倾斜度，因为倾斜度会影响水分状况和颗粒沉积。我们测量了苔藓垫层下的pH值，并将其与附近的裸树皮进行比较。此外，我们将结果与用中性覆盖物覆盖的实验树皮进行了比较。我们发现，裸树皮的pH值随着树干倾斜度的降低而下降。虽然苔藓覆盖物一般不会改变树皮的pH值，但与倾斜度存在显著的相互作用：倾斜度较高时，苔藓会降低树皮的pH反应，而倾斜度较低时，苔藓会提高树皮的pH反应。一种可能的解释可能在于碱性颗粒沉积的变化，或者相反在于树皮通过淋溶而酸化。此外，一项使用中性覆盖物的实验表明，覆盖裸树皮会大幅提高pH值。由于平均而言，苔藓不会改变树皮的pH值，树皮覆盖物本身的碱化作用与苔藓的酸化生物作用之间可能存在相互干扰。
