Crop responses to climate and socioeconomic change in northern regions

Climate, farmers’ actions and previous cultivation history influence regional crop yields and drive autonomous adaptation in time. Proceeding climate change will induce needs for various adaptation measures in the future, especially in the northern regions. We investigated how farms take advantage of novel opportunities in Finland as dictated by the biophysical environment, farmer experience and knowledge, and the dynamics of the socioeconomic environment. Using Finland as a case, we aimed to characterize the relation of regional climate and yield development of the four major cereal crops since 1965 and of spring rape since 1978. Yields in the northernmost regions were most responsive to growing season temperature sum and precipitation. However, yield levels in southern relative to northern and eastern areas have polarized through the period, which might be an indication of a socioeconomic rather than a climate-related response. As socioeconomic factors can be more deterministic for targeting autonomous adaptation on farms, regionally planned proactive adaptation strategies are needed to prepare for long-term changes such as the climate change.     

Evaluation of XRF and LIBS technologies for on-line sorting of CCA-treated wood waste

Contamination of wood waste with chromated copper arsenate greatly limits recycling opportunities for the wood waste as a whole. Separation of CCA-treated wood from other wood types is one means by which such contamination can be removed. The purpose of the current study was to evaluate two detector technologies for sorting CCA-treated wood from other wood types. The detector technologies evaluated included X-ray fluorescence spectroscopy (XRF) and laser induced breakdown spectroscopy (LIBS). The XRF detector system utilized in this study was capable of rapidly detecting the presence of CCA in painted wood, wet wood, heartwood, sapwood, and at portions of the wood containing knots. Furthermore, the XRF system was capable of distinguishing between CCA-treated wood and wood treated with alternative wood treatment preservatives, but was limited by the fact that it was not designed for on-line operation so tests were conducted in a batch mode on a conveyor. The analysis time used in this study (3 s) can be decreased significantly for an XRF system designed specifically for on-line operation. The LIBS system developed for this study was found to effectively identify CCA-treated wood for pieces ranging in thickness from 1 to 8 cm. High sorting efficiencies were noted when 10 laser shots were taken on a piece of wood. Furthermore, the LIBS system was found to be effective for identifying wood that has been coated with stains and paints in addition to identifying wood that has been CCA treated. The major drawback with the LIBS system developed in this study was the limited laser pulse energy. With an increase in laser pulse energy it is anticipated that the working focal length of the LIBS system can be increased to enable the monitoring of wood samples of more variable thicknesses. Limitations associated with analysis of very rotted pieces of wood and wet wood can also be overcome by using a higher pulse energy laser. Overall, both technologies show incredible promise for sorting CCA-treated wood from other wood types. The next recommended step would be to run an improved full-scale operation at one facility to document sorting efficiencies and fine-tune the improvements proposed in the current study. Such a study could potentially open-the-door for more widespread sorting of wood waste.     

Atmospheric aerosol growth rates at different background station types

Environmental Science and Pollution Research - Highly time-resolved particle number size distributions (PNSDs) were evaluated during 5 years (2013–2017) at four background stations in the...     

Evaluation of photolysis and hydrolysis of atrazine and its first degradation products in the presence of humic acids

Relative importance of hydrolysis and photolysis of atrazine and its degradation products in aqueous solutions with dissolved humic acids (HA) has been assessed under exposure to sunlight and under UV irradiation. Quantum yield for direct photolysis of atrazine at 254 nm was 0.037 mol photon(-1), the reaction order was 0.8. Atrazine, desethylatrazine and desisopropylatrazine converted to their 2-hydroxy analogs with rate constants 0.02-0.08 min(-1) in clear solutions, while addition of HA (300 mg L(-1)) caused a 10-fold increase in rate constants. Hydroxyatrazine was not degraded. No evidence of photo-Fenton reaction was found. Under exposure to solar light, atrazine, desethylatrazine and desisopropylatrazine were converted to 2-hydroxy analogs only at pH 2 because of acid hydrolysis and possible contribution of photolysis. At lower HA concentration, only their light-shielding effect was noticed, while at higher concentrations, HA-catalysed hydrolysis prevailed. Hydroxyatrazine concentration diminished at all pH values in solutions without HA exposed to sunlight.     

In search of human-associated bacterial pathogens in Antarctic wildlife: report from six penguin colonies regularly visited by tourists

We investigated the potential role of Antarctic tourism in the introduction of human-associated pathogens into Antarctic wildlife. We collected and analyzed 233 fecal samples from eight bird species. The samples were collected at six localities on the Antarctic Peninsula, which often is visited by tourists. Every sample was investigated for pathogens of potential human origin: Campylobacter jejuni, Salmonella spp., and Yersina spp. None of these bacteria was found. Our data suggest that the tourism industry so far has achieved its goal of not introducing pathogens into the Antarctic region. There is, however, an urgent need to further investigate the situation in areas closer to permanent Antarctic settlements.     

Optimization of a methodology for the determination of organochlorine pesticides in surface water by SPME-GC/MS

In the present work experimental conditions were optimized for the analysis of organochlorine traces in water matrix using solid-phase microextraction (SPME) followed by gas chromatography with mass selective detector. The parameters including time of exposure of the fiber in the aqueous sample, fiber type, agitation speed, pH, ionic forces, temperature of adsorption, and time of desorption were evaluated. The best conditions to analyze organochlorine were obtained by using higher than room temperature, agitation of the sample, extraction time of 40 min, and polyacrylate fiber.     

Bayesian testing for trend in a power model for clustered binary data

Developmental toxicity studies are widely used to investigate the potential risk of environmental hazards. In dose–response experiments, subjects are randomly allocated to groups receiving various dose levels. Tests for trend are then often applied to assess possible dose effects. Recent techniques for risk assessment in this area are based on fitting dose–response models. The complexity of such studies implies a number of non-trivial challenges for model development and the construction of dose-related trend tests, including the hierarchical structure of the data, litter effects inducing extra variation, the functional form of the dose–response curve, the adverse event at dam or at fetus level, the inference paradigm, etc. The purpose of this paper is to propose a Bayesian trend test based on a non-linear power model for the dose effect and using an appropriate model for clustered binary data. Our work is motivated by the analysis of developmental toxicity studies, in which the offspring of exposed and control rodents are examined for defects. Simulations show the performance of the method over a number of samples generated under typical experimental conditions.     

Comparison of inorganic and composite ferric oxide sorbents for arsenic removal

Three different sorbents based on hydrated ferric oxide (GEH, ArsenX^np and Lewatit FO 36) were compared from the viewpoints of their column operation. Particle size distribution, pressure drop across the column and ferric oxide content were measured. Sorption capacities under the presence of accompanying ions were measured in batch wise and column experiments.     

Volatile fatty acid evolution in biomass mixture composts prepared in open and closed bioreactors

In this study we observed the production of volatile fatty acids (VFAs) during the composting process of compost heaps in two different bioreactors (open and closed) at three different depths (0, 40 and 80 cm). The compost was prepared as a mixture of bio-waste, horse manure, grass and sawdust to ensure sufficient pH conditions in compost heaps. VFA contents in the composting materials were analysed weekly over 14–119 d. The degradation process was monitored, along with temperature, pH, total organic carbon, oxidizable carbon and mono- and oligosaccharides. VFA contents were evaluated with regard to the depth of the sample site in the compost heap and to conditions in the bioreactors. The maximum VFA occurrence was observed during the first 35 d; acetic and propionic acids in particular were determined to occur in each sample. Considerable variations in their formation and elimination were observed in the two bioreactors as well as at the various depths in the compost heaps. Significant correlations were found between individual VFAs, as well as between VFA concentrations and organic carbon contents.     

The concept of the Portuguese National Ecological Reserve: constraints and impossibilities in the Azores Archipelago

The biophysical features of small islands (SI) distinguish them from other territories; isolation, small size and several anthropogenic pressures reduce the resilience of ecosystems and increase their vulnerability to global changes. Many SI have a shortage of infrastructures, institutions and technical/financial resources that hinder planning and require different integrated solutions. In Portugal, the National Ecological Reserve (NER) is legally binding for spatial planning instruments. It aims to defend natural values and areas of ecological value, or sensibility, or susceptible to natural hazards. However, the criteria for the design of NER are strictly set for mainland territory, not taking into account specific features of small islands. A case study of the Azores Archipelago is used to demonstrate that spatial planning instruments should be adapted to island contexts. Such adaptation will increase the effectiveness of their implementation in relation to the protection of natural resources, stability of biophysical structures and prevention of natural hazards. Observing the main differences between mainland and the Azores Archipelago it is possible to define a methodological transposition of the NER aims and goals into an island context. This approach is an answer to the constraints in effective adaptation of spatial planning instruments for islands.