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Plants accumulating heavy metals in the Sudety Mts

63%
The Sudeten flora consists of some plants we can recognize as heavy metal accumulators. Between others there are: Thlaspi caerulescens, Arabidopsis halleri, Armeria maritima ssp. halleri s.l. and probably the endemic fern Asplenium onopteris var. silesiaca. The authors present the concentrations of some important heavy metals measured in aboveground plant dry weight. The highest concentration of zinc was 8220 ppm (Thlaspi), nickel - 3100 ppm (Thlaspi), lead - 83 ppm (Armeria), copper - 611 ppm (Arabidopsis) and cadmium - 28 ppm (Thlaspi). The concentrations depend rather on species or population specification than on ore deposit quality. There are no typical hyperaccumulator among plants we have examined, but some signs of hyperaccumulation of nickel, zinc and lead could be observed. There are no typical endemic taxa, only Asplenium onopteris var. silesiaca and Armeria maritima ssp. halleri may be recognized as neoendemic taxa, but still of unclear systematic position. During the study we tried to find out why some Sudeten vascular plants do not develop heavy metals hyperaccumulation and why they are rather latent hyperaccumulators. Finally, we suggest to protect some metallicolous areas in spite they are rather territories with low plant biodiversity.
Representatives of the Fallopia genus: Fallopia japonica, Fallopia sachalinensis and Fallopia × bohemica are known as successful invaders, wide spread throughout Europe and North America. This paper focuses on the invasive Fallopia complex and presents some features (a wide ecological amplitude, high competition abilities, sexual reproduction by hybridization) responsible for the fact that all species of the Fallopia genus are aggressive and noxious invaders.
Biological invasions are one of the main problems of contemporary ecology. When considering invasive species a special attention should be paid to Asian weeds of Fallopia genus (knotweeds): Fallopia japonica, Fallopia sachalinensis, and their hybrid – Fallopia × bohemica, which is the most troublesome species among the Fallopia complex. The aim of this research was to determine distribution of three Fallopia taxa in urban environments using the example of the one of the largest Polish cities, Wrocław, and preferences of the examined species regarding their inhabiting different habitats in urban ecosystems. The presence of knotweeds was confirmed in over 23.0% of urban areas. The most commonly recorded species was Fallopia japonica, while Fallopia sachalinensis (a donor of pollen for female clones of Fallopia japonica) was rare. Despite this fact, their highly invasive hybrid occurs in approximately 6.8% of urban areas and accounts for 21.6% of the total number of all knotweed clones. It suggests that expansion of Fallopia × bohemica in the city advances, in most cases, in a vegetative way (as a result of rhizome regeneration).The highest number of knotweed sites was recorded in ruderal and greenfield sites, including, among others, illegal waste dumps, heaps, rubble, and debris fields. The investigation has shown that in urban conditions knotweeds are able to spread on soil with various pH ranges and nutrient content. Also, the higher content of heavy metals does not limit the expansion of Fallopia weeds – on the contrary, it can even enhance their competitiveness in relation to other plant species, which avoid toxic concentrations of heavy metals.
The paper presents the results of several years investigations (2003-2007) on two invaders: the Himalayans Impatiens glandulifera and Asiatic Reynoutria japonica. The Sudety Mountains and their national parks are under strong pressure of both species, threatening the local vegetation. The four-year investigations have been carried out in field, glasshouse and in laboratory. Invasive species have their peculiar life histories which help them to occupy new areas. Those are above all the specific generative reproduction strategies (Impatiens) or vegetative reproduction strategies (Reynoutria). Both strategies secure the reproductive success and to capture more and more highly situated areas of the mountains. Very significant characteristics connected with the expansion of invaders is the excessively over and above the average production of seeds (Impatiens) and a huge annual increment aboveground biomass (Reynoutria). The investigated invasive species are probably not equipped with influence of allelopatic type as of greater importance is their competitive strength. The invaders can eliminate a part of the early spring flora belonging to the geophyte group and impoverish the regional biological diversity. Both the invasive plants enter also into some moist mountain forest communities.
In this study highly invasive plant species from the Fallopia genus (Fallopia japonica and Fallopia ×bohemica) were investigated for their ability to accumulate heavy metals. Samples were collected from two large cities: Wroclaw and Prague. The content of Cr, Cd, Fe, Pb and Zn in soils covered by Knotweed taxa was determined. Afterwards, plant samples were collected from the places where the largest amounts of toxic metals were found. Rhizomes, roots and leaves of chosen samples of both Fallopia taxa have been treated separately, as different parts of the plant accumulate metals. The investigation has shown that in urban conditions Knotweed taxa spread on soils with higher than natural concentration of toxic metals. Only the chromium amount was similar to the normal range. In both species heavy metals were accumulated mainly in roots and rhizomes, but their concentration was significantly higher in Fallopia japonica underground parts than in the hybrid. There were no differences between species with metals content in the aboveground parts of the plant body. The results suggest that special attention should be paid to Cr. In all analyzed plants, high chromium content was found, while the Cr amount in soils samples was close to natural.
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