Application of plants in remediation of contaminated sites

The concern for environmental protection has existed since the time of first human civilization. As society develops, the chain of changes during the natural flow of processes in ecosystems has been supplemented by a new link - pollutants. They have an effect on all other members of the ecosystem (changes may be visible immediately or harder to spot), which leads to an extremely complex relationship with nature. The values of some parameters of pollutants reached an alarmingly high level. The tendency to reduce the risk of air, soil, water, plant, and animal pollution to a tolerable limit, which would salvage the environment and most importantly human health, became a global problem. Heavy metals as pollutants have been an interest of researchers for their conduct, especially in forest ecosystems, which has been expressed in the previous year's more than ever. With its numerous toxic effects, heavy metals are endangering the existence of plant species that live in already contaminated environments. This is all an argument regarding the fight of modern society that the emission of polluted materials gets reduced in order to avoid multiple negative effects, which can endanger the existence of living organisms in general, as an argument for the continuation of numerous researches that are conducted in this area. The monitoring of heavy metals is of significant importance because their toxicity and accumulations are vital for the ecosystem. Polluted soils can be reduced and they can restore their function using physical, chemical, and biological techniques. Physical and chemical methods are very expensive and cause mainly irreversible changes, thus destroying biological variety. The biological recovery of contaminated soil represents an efficient method of reducing health risks for both mankind and the ecosystem.  For this purpose, biological indicators are used. Numerous researches have led to improvements of the initial idea about using plants as a remediation of the environment and the removal of different contaminants from contaminated medias into promising technologies of environmental protection under the title "Phytoremediation". This technology consists of the reduction of concentrations of polluted materials in polluted soils, water, or air. Plants have the ability to store, degrade, or eliminate metals, pesticides, solutions, explosives, and crude oils. Its derivatives and various other contaminants form mediums that contain them. This paper especially considers methods of the possibility of the usage and application of plants in restoring soil contaminated by heavy metals as well as other pollutants

Relationships between leaf traits and morphological attributes in one-year bareroot Fraxinus anguslifolia Vahl. seedlings

Leaf traits were investigated as morphological attributes for quality estimation of one-year-old bareroot seedlings of Fraxinus angustifolia Vahl. Leaf traits (number of simple - NSL and compound leaves - NCL, leaf average - ALA and total area - TLA and leaf area ratio - LAR) show similar relations to morphological attributes, the strongest to shoot growth (height - HT, root collar diameter - DIA and shoot dry weight - SDW). Increases of seedling morphological attributes are strongly related to increases of ALA. Given to strong positive correlations with other morphological attributes, ALA (R = 0.68-0.88) and TLA (R = 0.46-0.92) are suitable for seedlings quality testing. TLA explained a larger proportion of the variation of SDW (R-2 = 0.85) and ALA explained a large proportion of the variation of DIA (R-2 = 0.81). Leaf traits can be considered as valuable morphological attributes of seedling quality, in addition to strong correlation with other morphological attributes

Concentrations of manganese and iron in some woody and herbs plants

Heavy metals are the substances that indicate environmental pollution. The plants polluted with heavy metals may endanger natural environment and cause health problems in humans. In our multidisciplinary research of the concentrations of pollutants in forest ecosystems and natural environment in Belgrade, we examined the contents of heavy metals essential for plants but harmful in greater concentrations on a long-term basis. The fact that heavy metals manganese and iron are accumulated in plants to the greatest extent focused our work on determination of the level of concentrations of Mn and Fe in the vegetative parts of 8 plant types on three locations on the Avala Mountain and one location in the centre of the city of Belgrade. The analyses of heavy metals contents in plants were performed by the method of flame atomic absorption spectrophotometry. The examination of the existence of important differences between the average values was performed by implementation of Duncan’s test for the level of significance of 95%. The current contents of heavy metals in plants in the area of the protected natural resource Avala do not represent danger that would presently cause notable damage to forests but show the tendency of the increase of concentrations. Therefore, this issue should be constantly monitored

The incidence of Pyrenochaeta terrestris in root of different plant species in Serbia

Root samples of cereals (oats, wheat, barley, maize and sorghum), vegetables (garlic, onion, pepper, cucumber, pumpkin, carrot and tomato), industrial plant (soya bean) and weeds (Johnson grass, barnyard grass and green bristle-grass) collected in different agroecological conditions in Serbia were analysed for the presence of Pyrenochaeta terrestris. The fungus was found in 42 out of 51 samples (82.4%), while the incidence varied from 2.5 to 72.5%. The highest incidence was detected in cereals (average 30.3%), and then in weeds of the Poaceae family (average 14.2%). Considering single species, maize (up to 72.5% in root) and Johnson grass (up to 37.5%) were mostly attacked by this fungus. The lowest incidence of the fungus was determined in vegetable crops (average 6.7%). Red to reddish discoloration of root was correlated with the incidence of the fungus. Obtained data indicate that P. terrestris is widespread in Serbia and conditions for its development are favourable. [Projekat Ministarstva nauke Republike Srbije, br. TR-31023

Analysis of forest vegetation in Koviljski Rit: Comparison of habitats with varying degrees of anthropogenic influence

Koviljski Rit is located along the left bank of the Danube River, between the villages of Kovilj and Gardinovci. It is a rare example of pristine nature, where the original features of a swamp biotope are preserved. Because of its exceptional natural value, Koviljski Rit, along with the swamp in Petrovaradin, has been under the protection of the Republic of Serbia since 1998, when it was proclaimed a Special Nature Reserve of the first category. Natural vegetation found in Koviljski Rit includes woodlands composed of willow and poplar. The majority of the reserve consists of forest plantations (55.6%), which include habitats influenced by human activities. Based on DCA (Detrended correspondence analysis) of forest vegetation in Koviljski Rit, there is a high degree of similarity between natural populations of white willow and stands of anthropogenic origin. However, in contrast, the same analysis indicates clear differences between natural and artificial poplar stands. Moreover, depending on whether they were planted in temporary or permanent flood plain habitats, significant differences are evident in the floristic structures of Euro-American poplar forests. Ecological conditions in habitats of white and Euro-American poplar (Populus x euroamericana/Dode/ Guinier) communities were found to be more similar with respect to illumination and soil humidity. However, more importantly, the anthropogenic forests recorded the lowest diversity as a result of regular thinning and measures implemented through forest management. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. III 43002: Biosensing technologies and global system for continuous research and integrated management of ecosystems and Grant, no. 31,041th: Forest plantations as a way to increase reforestation in Serbia