Abstract
Our knowledge of the effects of increased ultraviolet‐B (UV‐B) radiation on terrestrial ecosystems is reviewed, with an emphasis on recent literature. The review starts with an overview of the effects on biomolecules and cells, plant cells in particular, and continues with effects on whole organisms: agricultural crops, trees, plants in natural ecosystems, and animals. Then effects of increased UV‐B on interactions between plants and other organisms, and effects of increased UV‐B in combination with other abiotic factors are described. The final part of the review deals with effects of UV‐B on plant litter decomposition and nutrient availability. It is concluded that UV‐B effects on interactions between organisms are probably more important than the direct effects of UV‐B on the organisms, with the possible exception of direct effects on perennial plants. In members of the letter category, radiation damage may accumulate from year to year.