Characterization of 14C-naphthol uptake in excised root segments of clover (Trifolium pratense L.) and fescue (Festuca arundinaceae Screb.)

An isolated root uptake test (IRUT) was used to characterize the bioaccumulation of ¹⁴C-naphthol in excised root segments obtained from 6-month-old hydroponically grown plants: two varieties of fescue (Festuca arundinaceae Schreb.) and one variety of clover (Trifolium pratense L.). Naphthol uptake rates were directly related to naphthol concentration in the range 0.01 to 0.2 uM. The incubation time required for equilibrium to be reached between naphthol in root tissue and in solution was between 9 and 12 h. Tests using metabolic inhibitors, KCN, NaN₃, and DNP, indicated that naphthol uptake may be the result of both passive and active mechanisms. Q₁₀ values for naphthol uptake ranged from 1.05 to 1.16.     

A fully reproductive fighting morph in a soldier clade of gall-inducing thrips (Oncothrips morrisi)

We present the first life history data for Oncothrips morrisi, a species in a clade of haplodiploid, Australian gall-inducing thrips that has a micropteran fighting morph in the first generation of the gall. Micropterans in other species in the clade have lower fecundity than their mother, and these species are considered eusocial. There is no such reproductive skew in O. morrisi, and the species is not eusocial by any definition. The volume of O. morrisi galls is between 4 and 20 times greater in than eusocial species in the clade and the dispersing-brood size varies between 5 and 15 times larger than that of other species. The lack of skew in O. morrisi could be associated with large gall volume, reducing competition between females for space and feeding sites for their offspring. As O. morrisi is in a lineage basal to eusocial Oncothrips, we also discuss selective factors for the evolution of a non-dispersing fighting morph in this clade. The costs involved in dispersal and latency to reproduction may have lowered the selective threshold for the evolution of a non-dispersing morph. Once non-dispersal evolved, selection to defend one's offspring may have promoted the evolution of soldier-like morphology and behaviour.     

Minderung von Lärmimmissionen des Kfz-Verkehrs

Although the permissible emission limits for new motor vehicles are continuously being reduced year after year, the proportion of citizens in the Federal Republic of Germany who are affected by such traffic noise continues to remain practically constant. Thus, aside from the innovations in motor-vehicle technology, the question must be raised concerning what other possibilities are actually available for achieving a reduction in the emission of traffic noises. In the following, planning possibilities are presented for the traffic routes themselves and for their direct vicinities. An evaluation is also made concerning their efficiency. In addition to the prognostic tools of the guidelines which have been introduced in Germany and Austria, the application of modern research must also be taken into consideration.     

On airborne nano/micro-sized wear particles released from low-metallic automotive brakes

The paper addresses the wear particles released from commercially available “low-metallic” automotive brake pads subjected to brake dynamometer tests. Particle size distribution was measured in situ and the generated particles were collected. The collected fractions and the original bulk material were analyzed using several chemical and microscopic techniques. The experiments demonstrated that airborne wear particles with sizes between 10 nm and 20 μm were released into the air. The numbers of nanoparticles (<100 nm) were by three orders of magnitude larger when compared to the microparticles. A significant release of nanoparticles was measured when the average temperature of the rotor reached 300 °C, the combustion initiation temperature of organics present in brakes. In contrast to particle size distribution data, the microscopic analysis revealed the presence of nanoparticles, mostly in the form of agglomerates, in all captured fractions. The majority of elements present in the bulk material were also detected in the ultra-fine fraction of the wear particles.     

Feeding behavior and acquisition of zooxanthellae by planula larvae of the sea anemone Anthopleura elegantissima

Symbiotic associations between cnidarians and photosynthetic dinoflagellates (i.e., zooxanthellae) are common in the marine environment. Many symbiotic cnidarians produce offspring that are initially nonsymbiotic. These new hosts must acquire symbiotic algae from environmental sources. We examined zooxanthella acquisition by laboratory-reared planula larvae of the temperate sea anemone Anthopleura elegantissima. Larvae ingested zooxanthellae while they were feeding. However, the signal that prompted larval feeding behavior did not originate from the symbiotic algae; the addition of algal cells to larval cultures never elicited a feeding response. In contrast, the addition of macerated animal tissue from several sources invariably generated a strong feeding response, which resulted in the larvae indiscriminately ingesting any particulate matter that was present, including zooxanthellae or other unicellular algae. Ingested zooxanthellae were incorporated into endodermal cells, where they remained undigested, while all other ingested material was digested or expelled within 24 h. Our results provide evidence that one source of zooxanthellae likely to serve as a route of infection in the natural environment is zooxanthella-laden mucus egested by anemones. This egested material fulfilled both of the criteria necessary for successful infection: it prompted larvae to begin feeding and provided an abundant supply of zooxanthellae that were ingested and taken up into endodermal cells of the new host.     

Evaluating recycling fertilizers for tomato cultivation in hydroponics,and their impact on greenhouse gas emissions

Soilless culture systems offer an environmentally friendly and resource-efficient alternative to traditional cultivation systems fitting within the scheme of a circular economy. The objective of this research was to examine the sustainable integration of recycling fertilizers in hydroponic cultivation—creating a nutrient cycling concept for horticultural cultivation. Using the nutrient film technique (NFT), three recycling-based fertilizer variants were tested against standard synthetic mineral fertilization as the control, with 11 tomato plants (Solanum lycopersicum L. cv. Pannovy) per replicate (n = 4) and treatment: two nitrified urine-based fertilizers differing in ammonium/nitrate ratio (NH₄⁺:NO₃^?), namely (1) “Aurin” (AUR) and (2) “Crop” (CRO); as well as (3) an organo-mineral mixture of struvite and vinasse (S+V); and (4) a control (NPK). The closed chamber method was adapted for gas fluxes (N₂O, CH₄, and CO₂) from the root zone. There was no indication in differences of the total shoot biomass fresh matter and uptake of N, P and K between recycling fertilizers and the control. Marketable fruit yield was comparable between NPK, CRO and S+V, whereas lower yields occurred in AUR. The higher NH₄⁺:NO₃^? of AUR was associated with an increased susceptibility of blossom-end-rot, likely due to reduced uptake and translocation of Ca. Highest sugar concentration was found in S+V, which may have been influenced by the presence of organic acids in vinasse. N₂O emissions were highest in S+V, which corresponded to our hypothesis that N₂O emissions positively correlate with organic-C input by the fertilizer amendments. Remaining treatments showed barely detectable GHG emissions. A nitrified urine with a low NH₄⁺:NO₃^– (e.g., CRO) has a high potential as recycling fertilizer in NFT systems for tomato cultivation, and S+V proved to supply sufficient P and K for adequate growth and yield. Alternative cultivation strategies may complement the composition of AUR.

     

Hierarchical Bayesian strategy for modeling correlated compositional data with observed zero counts

This article proposes a hierarchical multivariate conditional autoregressive model applied to a compositional response vector. We particularly focus on situations when the composition is discrete occurring when observations are based on small multinomial counts. We address drawbacks that exist in current modeling approaches for such data. Our hierarchical model will be demonstrated with data used to help manage a commercial sockeye salmon fishery in the Fraser River of British Columbia.     

Schadstoffbelastete Erzeugnisse im Verbraucherbereich: Wird REACH zu Verbesserungen führen?

Aim and Background Currently, the protection from hazardous substances occurring in consumer articles is often insufficient. In this paper, we discuss whether this situation will improve relevantly in the course of the implementation of the new European regulation on chemical substances (REACH). Changes under REACH may be heterogeneous. Therefore, differential effects depending on the tonnage as placed on the market, on the amount of substances contained in an article, and depending on timelines and exemptions for meeting the legal requirements, are discussed in this paper, together with a presentation of some uses of substances serving as examples. Discussion and Conclusions If substances are adequately registered, all identified and supported uses including their use in articles should be assessed. Therefore, where the full implementation of the registration conditions applies a substantial improvement may be expected due to REACH. Usually, producers or importers of articles are not required to register substances contained in these articles. Instead, the manufacturer or importer of the respective substance is usually responsible for registration, if exposure to the substance cannot be excluded and emission of the substance from an article is not the intended purpose. This may differ for substances intentionally released from articles. Additional obligations for substances not intentionally released mainly apply to substances of very high concern (SVHC). For the latter, the producer or importer of articles has to notify the European Chemicals Agency (ECHA) on the occurrence of the respective SVHC in articles. This information is important, especially because substances in imported articles may not be registered in advance. Authorisation within REACH is a very far reaching and effective tool of the legislation. However, authorisation is not required for SVHC imported as components of articles. Therefore, one main effect intended by REACH, i.?e. the substitution of SVHC, may possibly be undermined by importers of SVHC in articles. Restrictions, as specified in Annex XVII of REACH, offer a powerful opportunity to improve health and environmental safety with respect to hazardous substances. We support an extended understanding of what is defined as a “substance of concern” in the context of restrictions. This definition should be broader than just what is currently covered by the term SVHC. Consequences of restrictions may equally apply to European producers and importers of articles from outside of Europe, which contain such substances of concern. Another instrument currently closely linked to SVHC (in its more restricted definition), is the obligation of the producer or importer of articles to provide information according to article 33 (REACH). The downstream recipient of an article has to be informed on the content of SVHC in this article and how its safe use is ensured. Warehouses, wholesalers and other traders may therefore be aware of the SVHC contained in articles and may look for substitutes without such ingredients. Also, consumers may request this information on SVHC (just provided on demand) and are thus enabled to decide to buy other articles with less hazardous properties.     

Comparing contaminated property redevelopment for mandatory and Voluntary Cleanup Programs in California

This study uses California data to compare redevelopment for properties subject to mandatory and voluntary cleanup. CalSites are subject to the CERCLA liability approach, while properties in the Voluntary Cleanup Program (VCP) are subject to a risk-based approach (RBA) that allows some contamination to remain for non-residential redevelopment. The expectation is that VCPs will show a greater proportion of industrial redevelopment, which has the least stringent standard, and a smaller proportion of residential redevelopment. The results show an overall trend toward more residential redevelopment of contaminated properties, but consistent with expectations, the trend is weaker for VCP properties than CalSites.