Aronsson K Andreas, Ekelund Nils G A
Mid Sweden University, Department of Natural Sciences, 851 70 Sundsvall, Sweden.
Sci Total Environ. 2006 Dec 15;372(1):236-46. doi: 10.1016/j.scitotenv.2006.07.032. Epub 2006 Sep 1.
The application of wood ash from biofuel sources to the forest has been suggested as a source of nutrients for trees and for restoration of acidified soils and surface waters. Studies on the effects of wood ash on aquatic organisms and ecosystems are, however, few. This study investigated the effects of wood ash (0.1-10 g l(-1)) on the freshwater moss Fontinalis antipyretica Hedw., which has previously been shown to be a sensitive test organism for assessing environmental pollution. After nine weeks of treatment with wood ash, a significant effect of enhanced stem growth was observed at higher concentrations (1-10 g l(-1)). The concentration of wood ash was also correlated with the growth of secondary branches. Photosynthesis (oxygen evolution after 4 h of exposure to wood ash) was significantly lower in the alkaline treatments (no pH adjustment) compared to the treatments with neutral wood ash solutions (pH adjusted to 7.5). Furthermore, photosynthesis in the alkaline wood ash treatments was significantly lower compared to the control. The ratio between the optical density value before and after acidification (OD(665/665a)) was higher for all wood ash concentrations compared to the control. The OD(665/665a) values ranged from 1.52 to 1.61 and there was a difference, however not significant, between the alkaline and the neutral treatment at 10 g l(-1) wood ash. This study clearly demonstrated that wood ash may be beneficial for F. antipyretica at moderate concentrations (0.5-5 g l(-1)), particularly when a sudden increase in pH is avoided.
将生物燃料来源的木灰施用于森林，被认为是树木养分的一个来源，也可用于酸化土壤和地表水的修复。然而，关于木灰对水生生物和生态系统影响的研究却很少。本研究调查了木灰（0.1 - 10 g l(-1)）对淡水苔藓Fontinalis antipyretica Hedw.的影响，该苔藓此前已被证明是评估环境污染的敏感测试生物。用木灰处理九周后，在较高浓度（1 - 10 g l(-1)）下观察到茎生长增强的显著效果。木灰浓度也与次生枝的生长相关。与用中性木灰溶液（pH值调至7.5）处理相比，碱性处理（未调节pH值）下的光合作用（接触木灰4小时后的氧气释放量）显著降低。此外，碱性木灰处理下的光合作用与对照相比也显著降低。与对照相比，所有木灰浓度下酸化前后的光密度值之比（OD(665/665a)）都更高。OD(665/665a)值在1.52至1.61之间，然而在木灰浓度为10 g l(-1)时，碱性处理和中性处理之间存在差异，但不显著。本研究清楚地表明，适度浓度（0.5 - 5 g l(-1)）的木灰可能对F. antipyretica有益，特别是在避免pH值突然升高的情况下。
