Dipartimento di Chimica, Università degli Studi di Salerno, Via Ponte Don Melillo, 84084 Fisciano, SA, Italy.
Sci Total Environ. 2011 Feb 1;409(5):979-84. doi: 10.1016/j.scitotenv.2010.11.022. Epub 2010 Dec 16.
We determined the effects of tropospheric ozone on the chemical composition of Quercus ilex L. leaves and their decomposition, with a view to assessing the influence of ozone on nutrient cycling and the sustainability of Mediterranean holm oak forests. Forming one of the most widespread thermophilous vegetation communities in the area, Q. ilex is a dominant and widespread evergreen oak in the Mediterranean, where concentrations of tropospheric ozone are particularly high. The dynamics of carbon, nitrogen, lignin and cellulose concentrations were monitored for six months during the decomposition of leaves from plants subjected to controlled ozone exposure in open-top chambers. Ozone-exposed leaves, compared to unexposed leaves, showed no significant differences in C, N, lignin and cellulose concentrations prior to the incubation in mesocosms. However, during decomposition, leaves from plants exposed to ozone lost C significantly more slowly and showed a higher C/N ratio than unexposed leaves. Ozone exposure significantly slowed down the decomposition rate, indicating a negative effect of tropospheric ozone on nutrient cycling, which may reduce long-term sustainability of the holm oak forest.
我们研究了对流层臭氧对欧洲栓皮栎叶片化学组成及其分解的影响，旨在评估臭氧对养分循环和地中海常绿栎林可持续性的影响。欧洲栓皮栎是该地区分布最广泛的喜温植被群之一，是地中海地区分布广泛的优势常绿栎，该地区对流层臭氧浓度特别高。在敞顶箱中对受控臭氧暴露的植物叶片进行了为期六个月的分解过程中，监测了碳、氮、木质素和纤维素浓度的动态变化。与未暴露的叶片相比，在放入中尺度模型中进行孵育之前，臭氧暴露的叶片在 C、N、木质素和纤维素浓度方面没有显著差异。然而，在分解过程中，臭氧暴露的叶片中 C 的损失明显更慢，并且 C/N 比值高于未暴露的叶片。臭氧暴露显著减缓了分解速率，表明对流层臭氧对养分循环有负面影响，这可能会降低常绿栎林的长期可持续性。
