Regional evaluation of mass element fluxes: Geomon network of small catchments

Monitoring of element flows and their mass balances in the natural unit of the biosphere represented by a small catchment appears to be the most suitable for the solution of complex problems such as the deterioration of environmental quality. Long-term collection of comparable biogeochemical data, which will enable the identification of environmental trends, is the main aim of the GEOMON network. One of the most important applications of these data will be the calculation of critical loads. The Czech Geological Survey possesses data from 44 catchments in the former Czechoslovakia. Qualitative and quantitative data on inputs in atmospheric deposition and outputs via surface runoff are available. Simple input-output mass balances yield estimates of total accumulation or loss of individual components. Some examples of interpretations of the GEOMON data, especially in connection with different bedrock types, will be given.     

The response of Trissolcus basalis to footprint contact kairomones from Nezara viridula females is mediated by leaf epicuticular waxes

Chemical footprints left behind by true bugs are perceived as contact kairomones by scelionid egg parasitoids. Female wasps encountering a contaminated artificial substrate display a characteristic arrestment posture, holding the body motionless and antennating the surface. In the system Nezara viridula (L.) and its egg parasitoid Trissolcus basalis (Wollaston), previous studies have shown that the kairomone mediating such behavior is part of N. viridula’s cuticular hydrocarbons (CHC) and furthermore that the wasp’s ability to discriminate host male and female footprints is mainly based on the presence/absence of nonadecane (nC₁₉). In this study, the effect of epicuticular waxes of leaves of broad bean, Vicia faba, on wasp responses to footprints of N. viridula females were investigated. Approximately 20% of T. basalis females displayed an arrestment posture when released on the adaxial leaf surfaces of broad bean plants with intact wax layer and without host chemical contamination; whereas ∼70% of wasps displayed the arrestment posture when intact leaves were contaminated by host female footprints. Adaxial leaf surfaces of broad bean plants dewaxed with an aqueous solution of gum arabic and afterwards contaminated by N. viridula females induced arrestment responses in about 10% of female wasps; the same percentage of arrestment (10%) was observed when the wasps were released on leaves contaminated by host females and subsequently dewaxed. The side of the polymer film that was appressed to the leaf surface, peeled from the contaminated leaves, induced an arrestment posture in about 95% of observed wasps. Scanning electron microscopy (SEM) revealed that the epicuticular waxes occurred as a film densely crystallized as irregularly shaped platelets with spherical granules randomly distributed. These findings demonstrated that epicuticular waxes of broad bean leaves can mediate the foraging behavior of T. basalis females by absorbing contact kairomones of the host.     

Cancer and occupational exposure to pesticides: a bibliometric study of the past 10 years

Environmental Science and Pollution Research - Occupational exposure to pesticides has been identified as a major trigger of the development of cancer. Pesticides can cause intoxication in the...     

Circular economy for durable products and materials: the recycling of plastic building products in Germany—status quo,potentials and recommendations

Journal of Material Cycles and Waste Management - The construction sector is the second largest area for the application for plastics. Due to the long life times of construction products, the...     

Assessment of macro and microelement accumulation capability of two aquatic plants

The concentrations of four macroelements (C, N, P, S) and eight trace metals (Cd, Cr, Cu, Fe, Mn, Ni, Pb, Zn) were measured in the leaves and roots of the emergent plant, Phragmites communis Trin., and in the shoots and roots of the submersed Najas marina L., taken from Lake Averno (Naples, Italy). Phragmites communis leaves showed higher concentrations of carbon, nitrogen and phosphorus than roots, while the roots exhibited significantly higher concentrations of sulphur and trace metals. Najas marina roots also showed higher concentrations of sulphur and trace metals than shoots, but these differences were less marked than in Phragmites communis except for sulphur. Sulphur was the only macronutrient to show the highest concentrations in the roots. Phragmites communis roots had higher values of Cr, Cu, Fe, Mn and Ni than Najas marina roots. By contrast, Cd, Cr, Fe, Ni, Pb and Zn concentrations were higher in Najas marina shoots than in Phragmites communis leaves. Phragmites communis, available through the year, showing high capability to accumulate trace metals in the roots, appears a good monitor of lake contamination, better than Najas marina.     

Lateral flow assay applied to pesticides detection: recent trends and progress

Environmental Science and Pollution Research - Devices based on lateral flow assay (LFA) have been gaining more and more space in the detection market mainly due to their simplicity, speed, and low...     

Slow pyrolysis of olive mill solid residues as a sustainable valorization strategy for waste biomass

Journal of Material Cycles and Waste Management - Pyrolysis is a valid thermos-chemical process of energy production that produces biochar from potentially harmful biomasses. This study aims to...