engleski

The anual changes of chloroplast pigments content in currenr- and previous-year needles of Norway spruce (Picea abies L. Karst.) exposed to cement dust pollution

Chloroplast pigments were shown to be very sensitive to various environmental influences. Changes in chlorophyll and carotenoid content were investigated in Norway spruce needles exposed to alkaline dust emitted by the cement industry. Pigments were extracted from current-year and previous-year needles and quantified spectrophotometrically. In both needle generations all measured pigments were reduced in dust-exposed needles compared to needles harvested from areas not polluted by cement dust. This was due to deceleration of the biosynthetic processes rather than degradation of pigments. Chlorophyll b content appeared to be more sensitive than chlorophyll a in current-year needles while in previous-year needles chlorophyll a was more affected. Total carotenoids needed a longer period of time to reach nearly the same level as in controls. The progression of pigment decline in previous-year needles appeared not to be dramatically accelerated. It might thus be concluted that the spruce needles had sufficient biosynthetic capacity to prevent irreversible damage by cement dust.

Picea abies; chlorophyll; carotenoids; cement dust; air polution

nije evidentirano