Physiological and developmental processes of plants are affected by UVB radiation. Plants have a limited ability to adapt to increased levels of UVB. Excessive heat and ultraviolet light in the UVB (electromagnetic radiation) region of the spectrum can damage plant photo-systems, inhibit photosynthesis and weaken plant structure.
Indirect changes caused by UVB (such as changes in plant form, how nutrients are distributed within the plant, timing of developmental phases and secondary metabolism) may be equally, or sometimes more, important than damaging effects of UVB. These changes can have important implications for plant competitive balance, plant diseases, disruption in timing of developmental phases and secondary metabolism.
The severity of the damage can range from a decline in carbohydrates, reduced energy production and natural plant defense, to cell collapse and plant death.