Chemical composition of the leaves of Reynoutria japonica Houtt. and soil features in polluted areas

Abstract

Abstract:The study was conducted on six sites that are dominated by Japanese knotweed (Reynoutria japonica) and that vary in the level of industrialization and habitat transformation by humans. The aim of the research was to investigate the chemical-physical features of soil under a closed and dense canopy of R. japonica, the chemical composition of the R. japonica leaves, and to compare the content of certain elements in the soil-plant-soil system. The soil organic carbon (C org ) content varied from 1.38±0.004% to 8.2±0.047% and the maximum in leaves was 49.11±0.090%. The lowest levels of total nitrogen (N tot ) in soil were recorded on the heavily disturbed sites (till 0.227±0.021%). Soil pH varied greatly, ranging from acidic (pH=4.0) to neutral (pH=7.7). Heavy metal content differed significantly among the study sites. At all of the sites, both in the case of soil and plant leaves, Zn was a dominant element and its concentration ranged from 41.5 to 501.2 mg·kg -1 in soils and from 38.6 to 541.7 mg·kg -1 in leaves. ) were observed on the site that had been influenced by agricultural practices. The results obtained showed that R. japonica is able to accumulate high levels of heavy metals.

The influence of invasive Fallopia taxa on resident plant species in two river valleys (southern Poland)

“…With reference to the above, it can be stated that F. japonica is the most tolerant to high nitrogen variation in soil when compared to the remaining knotweed species. Concerning organic carbon, in our study soils were not very rich, as in the Belgium sites [36], but ours were more similar to the results obtained by Rahmonov et al [45] for F. japonica. Furthermore, the concentration of phosphorus in our soils was very variable as in sites in Belgium [36].…”

“…6.5., whereas in wasteland in Belgium it varied between 4.9 to 7.4 [36]. Also Rahmonov et al [45] showed that sites invaded by F. japonica are very diverse in pH, from 4.0 to 7.5.…”

“…As regards nitrogen, in our study we focused on nitrate and ammonium ions, which are the available forms of this chemical element for plants, whereas in the majority of studies (e.g. [36,45]) total nitrogen was analyzed and did not exhibit differences among sites [45]. Sites with a higher content of the two forms of available nitrogen were more associated with F. ×bohemica and, most of all, with F. sachalinensis but not with F. japonica, which partially confirms that the latter species can exist in areas with low available nitrogen [16].…”

Heavy metal accumulation in invasive Reynoutria × bohemica Chrtek & Chrtková in polluted areas

“…One study was conducted by Soltysiak et al (2011) in the Central European cities of Wroclaw and Prague, but it evaluated only five heavy metals (Cr, Cd, Fe, Pb and Zn). Previous studies mainly investigated different ecological and physicochemical characteristics of R. japonica (Nishizono et al 1989;Rahmonov et al 2014).…”

Nitrates and phosphates in cave waters of Kraków-Częstochowa Upland, southern Poland

“…Human activities have intensified the release of P by the year 2000; the global mobilisation of the nutrient had roughly tripled compared to its natural flows: increased soil erosion and runoff from fields, recycling of crop residues and manure, discharges of urban and industrial wastes, and, above all, application of inorganic fertilisers were the major causes of this increase (Smil 2000;Rahmonov et al 2014). An important element in the cycle and migration of phosphorus is the type of catchment management in relation to the annual outflow of phosphorus.…”