The impact of plant protection on the ecological state of the urban ecosystem in Kaliningrad

Iron is an essential heavy metal for plants. in hemoproteins (all cytochromes,catalase,peroxidase) and non-heme proteins (iron-sulphur clusters),iron is crucial to the functioning of redox systems of photosynthesis and respiration. this article studies the accumulation of iron in the soil/plant system of urban phytocoenoses in the city of kaliningrad. the authors analysed iron content in the accumulation horizon of urban soils (in agricultural/residential,residential,and industrial landscapes) and in tree,shrub,and herb species most common in urban landscapes (22 species). the maximum iron content in soils was observed in industrial and residential landscapes and high-rise residential areas with heavy traffic (2.1-2.8%). iron content in the leaves of urban plants was proven to depend on both iron concentration in the soil (r=0.92-1,0; p < 0,05) and the stage of vegetation. background iron levels in plants were studied. plant species actively accumulating iron were identified,namely,the silver birch (betula pendula),the small-leaved lime (tilia cordata) (545,1-647,5 mg/kg),the sweet mock-orange (philadelphus coronaries) (542.1 mg/kg),the white clover (trifolium repens) (740.6 mg/kg),the cock's foot (dactylis glomerata) (379.4 mg/kg),and the common dandelion (taraxacum officinale) (290.8 mg/kg). these species can be used in the phytoremediation of iron-contaminated urban areas. most plants tested showed a low rate of fe accumulation from the soil (a biological accumulation coefficient of 0.1-0.4). the bac significantly decreased in most species as iron content in the soil increased. plant species capable of limiting the uptake of iron from the environment were identified. the mn/fe,ni/fe,and co/fe ratios in soils from different functional areas were proven comparable. a low fe/mn ratio in the leaves of the norway maple (acer platanoides) was found indicative of irregular iron uptake. plants showing fe/mn ratios below control levels (philadelphus coronarius,achillea millefolium,trifolium repens) may be affected by iron toxicity. © 2017,university of mohammed premier oujda morocco.