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Plant growth on mine wastes is restricted by the lack of water, nutrients, phytotoxic responses and the absence of a seedbank. In a mesocosm study, we addressed the establishment of vegetation on metalliferous mine wastes from two seed mixtures. Besides the composition of the vegetation and the increase in plant cover and biomass over time, we studied concentrations of heavy metals in the shoot and analyzed the quantity of throughflow, its pH and EC to follow pollutant discharge. We hypothesized that the types of mine wastes and sown grasslands will affect species composition and the formation of a protective plant cover. Our platform was well-suited to study build-up and succession of a vegetation layer and its potential to stabilize mine wastes. However, the establishing community was less diverse than expected. The dilution of wastes increased species number and biomass, and we found a reduction of material discharge with increasing vegetation cover. Over time, drainage was reduced, while pH of the throughflow did not change. However, it was higher under the addition of greywater. Interestingly, the use of greywater led to a higher biomass in one mixture and slight changes in the chemistry of the throughflow and the plant matter.

Extraction and processing of cassiterite (SnO2) left large tailings with high concentrations of tin, tungsten, molybdenum and lithium. Information on the phytotoxicity of mine waste is important with regard to ecological hazards. Exposure studies help to identify plants useful for the stabilization of waste tips and the phytomining of metals. A greenhouse study was performed using a dilution series of mine waste and four crops, a halophytic and a metallophytic species to derive dose response curves. Based on effective doses for growth reductions, sensitivity increased in the following order: maize > common buckwheat > quinoa > garden bean. Element analyses in different species and compartments of common buckwheat grown in a mixture of standard soil and 25% of the mine waste showed that only low levels of the metals were taken up and that transfer to seed tissues was negligible. As indicated by soil metal levels prior to and after the experiment, only lithium and arsenic proved to be plant available and reached high levels in green tissues while seed levels were low. The experiment confirmed differences in the uptake of metals with regard to elements and species. Common buckwheat is a suited candidate for cultivation on metal polluted soils. © 2018 Taylor & Francis Group, LLC.

Having evolved a parasitic relation to their host plants, aphids may serve as indicators of plant responses to environmental changes. The present rise in atmospheric CO2 concentrations is expected to alter plant leaf chemistry and may thus alter host plant – aphid relations. We involved a climate chamber system and used bird cherry-oat aphid (Rhopalosiphum padi L.) and green peach aphid (Myzus persicae S.) and their respective host plants, spring wheat (Triticum aestivum L. cv. “Triso”) and oilseed rape (Brassica napus cv. “Campino”), to elucidate the effects of atmospheric CO2 enrichment on such bitrophic systems. Spring wheat grown at elevated CO2 (600 ppm) generally had greater above ground biomass than plants grown at ambient CO2 (400 ppm). Bird cherry-oat aphid infestation resulted in reduced spring wheat above ground biomass compared to the non-infested control. Relative crop growth rate (RGR) was increased by elevated CO2. In our study, the relative developmental stage (rDS) and intrinsic rate of increase (rm) of the aphids was only slightly and non-signifi cantly increased under elevated atmospheric CO2 conditions. The response of aphid weight and RGR to elevated CO2 differed, increasing by 24% and 18.2% for bird cherry-oat aphid and decreasing by 12% and 12.5% for green peach aphid, respectively. Aphids reared on spring wheat at elevated CO2 had a shorter lifespan, whereas the opposite effect was found for aphids reared on oilseed rape. The average number of nymphs of the two pest species showed both an increase under elevated CO2. No consistent picture emerges from these findings, and further investigation on host – aphid relations under changing atmospheric conditions such as CO2 enrichment appear necessary.

Dieses Positionspapier wurde vom Arbeitskreis Umweltmonitoring der GDCh-Fachgruppe Umweltchemie und Ökotoxikologie erarbeitet. In Teil 1 werden wichtige Begriffe definiert und gesetzliche Rahmenbedingungen sowie wissenschaftliche Grundlagen beschrieben, die für die Durchführung eines Umweltmonitorings relevant sind (Mitt. Umweltchem. Ökotox. 13(2), 2007, 34). In Teil 2 werden Hinweise zur konkreten Umsetzung von Monitoringprogrammen gegeben. Das gesamte Dokument mit zusätzlichen Beispielen ist auf den Internetseiten des AK Umweltmonitoring verfügbar.

Dieses Positionspapier wurde vom Arbeitskreis Umweltmonitoring der GDCh-Fachgruppe Umweltchemie und Ökotoxikologie erarbeitet. In Teil 1 werden wichtige Begriffe definiert und gesetzliche Rahmenbedingungen sowie wissenschaftliche Grundlagen beschrieben, die für die Durchführung eines Umweltmonitorings relevant sind. In Teil 2 werden Hinweise zur konkreten Umsetzung von Monitoringprogrammen gegeben. Das gesamte Dokument mit zusätzlichen Beispielen ist auf den Internetseiten des AK Umweltmonitoring verfügbar.

Effects of vapours of two herbicides on plantlets of fourteen wild higher plant species and two bryophytes were screened in fumigation experiments using foliar injury, chlorophyll fluorescence and growth as response parameters. After vaporisation of the herbicides for 48 h, concentrations in the chambers reached 77 g m−3 in the chlorpropham treatments and 184 ng m−3 in the ethofumesate treatments. Despite the higher concentrations of the volatile chlorpropham (vapour pressure, VP: 1.3 mP), plants showed no foliar injury, but vapours of this herbicide caused leaf crinkling in the agriophyte Agrostemma githago. The less volatile ethofumesate (VP: 0.56 mP) caused foliar injury in all higher species, with lowest no observed effect concentrations (NOECs) of 75 ng m−3. Chlorpropham affected growth only in Agrostemma, while ethofumesate reduced growth in one third of the higher plant species. Chlorophyll fluorescence proved to be a less suitable response parameter compared to foliar injury and growth. No adverse effects were observed in mosses, probably due to the slow growth and hence small doses of herbicides taken up. The extent of foliar injury due to ethofumesate showed a weak positive relationship to relative growth rates and specific leaf area in the tested higher plant species.