Turunen Minna, Latola Kirsi
Arctic Centre, University of Lapland, PO Box 122, FI-96101 Rovaniemi, Finland.
Environ Pollut. 2005 Oct;137(3):390-403. doi: 10.1016/j.envpol.2005.01.030.
Research has shown that some plants respond to enhanced UV-B radiation by producing smaller and thicker leaves, by increasing the thickness of epidermis and concentration of UV-B absorbing compounds of their surface layers and activation of the antioxidant defence system. The response of high-altitude plants to UV-B radiation in controlled conditions is often less pronounced compared to low-altitude plants, which shows that the alpine timberline plants are adapted to UV-B. These plants may have a simultaneous co-tolerance for several stress factors: acclimation or adaptation to the harsh climate can also increase tolerance to UV-B radiation, and vice versa. On the other hand, alpine timberline plants of northern latitudes may be less protected against increasing UV-B radiation than plants from more southern latitudes and higher elevations due to harsh conditions and weaker preadaptation resulting from lower UV-B radiation exposure. It is evident that more long-term experimental field research is needed in order to study the interaction of climate, soil and UV-B irradiance on the timberline plants.
研究表明，一些植物通过产生更小且更厚的叶子、增加表皮厚度和表层紫外线B吸收化合物的浓度以及激活抗氧化防御系统来应对增强的紫外线B辐射。与低海拔植物相比，高海拔植物在受控条件下对紫外线B辐射的反应通常不那么明显，这表明高山林线植物适应了紫外线B。这些植物可能对多种胁迫因素同时具有共同耐受性：对恶劣气候的驯化或适应也可以增加对紫外线B辐射的耐受性，反之亦然。另一方面，由于恶劣条件以及较低的紫外线B辐射暴露导致的较弱的预适应，北纬地区的高山林线植物可能比来自更南纬度和更高海拔的植物受到的紫外线B辐射增加的保护更少。显然，为了研究气候、土壤和紫外线B辐照度对林线植物的相互作用，需要进行更多长期的实验性田间研究。
