Increased bioavailability of metals in two contrasting agricultural soils treated with waste wood-derived biochar and ash

Recycled waste wood is being increasingly used for energy production; however, organic and metal contaminants in by-products produced from the combustion/pyrolysis residue may pose a significant environmental risk if they are disposed of to land. Here we conducted a study to evaluate if highly polluted biochar (from pyrolysis) and ash (from incineration) derived from Cu-based preservative-treated wood led to different metal (e.g., Cu, As, Ni, Cd, Pb, and Zn) bioavailability and accumulation in sunflower (Helianthus annuus L.). In a pot experiment, biochar at a common rate of 2 % w/w, corresponding to ～50 t ha^?1, and an equivalent pre-combustion dose of wood ash (0.2 % w/w) were added to a Eutric Cambisol (pH 6.02) and a Haplic Podzol (pH 4.95), respectively. Both amendments initially raised soil pH, although this effect was relatively short-term, with pH returning close to the unamended control within about 7 weeks. The addition of both amendments resulted in an exceedance of soil Cu statutory limit, together with a significant increase of Cu and plant nutrient (e.g., K) bioavailability. The metal-sorbing capacity of the biochar, and the temporary increase in soil pH caused by adding the ash and biochar were insufficient to offset the amount of free metal released into solution. Sunflower plants were negatively affected by the addition of metal-treated wood-derived biochar and led to elevated concentration of metals in plant tissue, and reduced above- and below-ground biomass, while sunflower did not grow at all in the Haplic Podzol. Biochar and ash derived from wood treated with Cu-based preservatives can lead to extremely high Cu concentrations in soil and negatively affect plant growth. Identifying sources of contaminated wood in waste stream feedstocks is crucial before large-scale application of biochar or wood ash to soil is considered.     

Climatic and environmental change in the Karakoram: making sense of community perceptions and adaptation strategies

In this paper, we investigate how mountain communities perceive and adapt to climatic and environmental change. Primary data were collected at community and household level through in-depth interviews, focus group discussions, and quantitative questionnaires covering 210 households in six villages of the West Karakoram (Hundur and Darkut in the Yasin Valley; Hussainabad, Altit, Gulmit, and Shiskat in the Hunza valley of Gilgit-Baltistan). The relevance of the area with respect to our scopes is manifold. First, this is one of the most extreme and remote mountainous areas of the world, characterized by complex and fragile institutional and social fabrics. Second, this region is one of the focal points of research for the hydro-meteo-climatological scientific community, because of its relevance in terms of storage and variability of water resources for the whole Indus basin, and for the presence of conflicting signals of climate change with respect to the neighboring regions. Third, the extreme hardships due to a changing environment, as well as to the volatility of the social and economic conditions are putting great stress on the local population. As isolating climate change as a single driver is often not possible, community perceptions of change are analyzed in the livelihood context and confronted with multi-drivers scenarios affecting the lives of mountain people. We compare the collected perceptions with the available hydro-climatological data, trying to answer some key questions such as: how are communities perceiving, coping with, and adapting to climatic and environmental change? Which are the most resorted adaptation strategies? How is their perception of change influencing the decision to undertake certain adaptive measures?     

Herbicide toxicity,selectivity and hormesis of nicosulfuron on 10 Trichogrammatidae (Hymenoptera) species parasitizing Anagasta ( = Ephestia) kuehniella (Lepidoptera: Pyralidae) eggs

Selective agrochemicals including herbicides that do not affect non-target organisms such as natural enemies are important in the integrated pest management (IPM) programs. The aim of this study was to evaluate the herbicide toxicity, selectivity and hormesis of nicosulfuron, recommended for the corn Zea mays L. (Poaceae) crop, on 10 Trichogrammatidae (Hymenoptera) species. A female of each Trichogramma spp. or Trichogrammatoidea annulata De Santis, 1972 was individually placed in plastic test tubes (no choice) with a cardboard containing 45 flour moth Anagasta ( = Ephestia) kuehniella Zeller, 1879 (Lepidoptera: Pyralidae) eggs. Parasitism by these natural enemies was allowed for 48 h and the cardboards were sprayed with the herbicide nicosulfuron at 1.50 L.ha^?1, along with the control (only distilled water). Nicosulfuron reduced the emergence rate of Trichogramma bruni Nagaraja, 1983 females, but increased that of Trichogramma pretiosum Riley, 1879, Trichogramma acacioi Brun, Moraes and Smith, 1984 and T. annulata females. Conversely, this herbicide increased the emergence rate of Trichogramma brasiliensis Ashmead, 1904, T. bruni, Trichogramma galloi Zucchi, 1988 and Trichogramma soaresi Nagaraja, 1983 males and decreased those of T. acacioi, Trichogramma atopovilia Oatman and Platner, 1983 and T. pretiosum males. In addition, nicosulfuron reduced the sex ratio of T. galloi, Trichogramma bennetti Nagaraja and Nagarkatti, 1973 and T. pretiosum and increased that of T. acacioi, T. bruni, T. annulata, Trichogramma demoraesi Nagaraja, 1983, T. soaresi and T. brasiliensis. The herbicide nicosulfuron was “harmless” (class 1, <30% reduction) for females and the sex ratio of all Trichogrammatidae species based on the International Organization for Biological Control (IOBC) classification. The possible hormesis effect of nicosulfuron on Trichogrammatidae species and on the bacterium Wolbachia sp. (Rickettsiales: Rickettsiaceae) was also discussed.     

Predictive Model of Avian Electrocution Risk on Overhead Power Lines

Electrocution on overhead power structures negatively affects avian populations in diverse ecosystems worldwide, contributes to the endangerment of raptor populations in Europe and Africa, and is a major driver of legal action against electric utilities in North America. We investigated factors associated with avian electrocutions so poles that are likely to electrocute a bird can be identified and retrofitted prior to causing avian mortality. We used historical data from southern California to identify patterns of avian electrocution by voltage, month, and year to identify species most often killed by electrocution in our study area and to develop a predictive model that compared poles where an avian electrocution was known to have occurred (electrocution poles) with poles where no known electrocution occurred (comparison poles). We chose variables that could be quantified by personnel with little training in ornithology or electric systems. Electrocutions were more common at distribution voltages (≤33 kV) and during breeding seasons and were more commonly reported after a retrofitting program began. Red‐tailed Hawks (Buteo jamaicensis) (n = 265) and American Crows (Corvus brachyrhynchos) (n = 258) were the most commonly electrocuted species. In the predictive model, 4 of 14 candidate variables were required to distinguish electrocution poles from comparison poles: number of jumpers (short wires connecting energized equipment), number of primary conductors, presence of grounding, and presence of unforested unpaved areas as the dominant nearby land cover. When tested against a sample of poles not used to build the model, our model distributed poles relatively normally across electrocution‐risk values and identified the average risk as higher for electrocution poles relative to comparison poles. Our model can be used to reduce avian electrocutions through proactive identification and targeting of high‐risk poles for retrofitting. Modelo Predictivo del Riesgo de Electrocución de Aves en Líneas Eléctricas Elevadas     

Vocal Activity as a Low Cost and Scalable Index of Seabird Colony Size

Although wildlife conservation actions have increased globally in number and complexity, the lack of scalable, cost‐effective monitoring methods limits adaptive management and the evaluation of conservation efficacy. Automated sensors and computer‐aided analyses provide a scalable and increasingly cost‐effective tool for conservation monitoring. A key assumption of automated acoustic monitoring of birds is that measures of acoustic activity at colony sites are correlated with the relative abundance of nesting birds. We tested this assumption for nesting Forster's terns (Sterna forsteri) in San Francisco Bay for 2 breeding seasons. Sensors recorded ambient sound at 7 colonies that had 15–111 nests in 2009 and 2010. Colonies were spaced at least 250 m apart and ranged from 36 to 2,571 m². We used spectrogram cross‐correlation to automate the detection of tern calls from recordings. We calculated mean seasonal call rate and compared it with mean active nest count at each colony. Acoustic activity explained 71% of the variation in nest abundance between breeding sites and 88% of the change in colony size between years. These results validate a primary assumption of acoustic indices; that is, for terns, acoustic activity is correlated to relative abundance, a fundamental step toward designing rigorous and scalable acoustic monitoring programs to measure the effectiveness of conservation actions for colonial birds and other acoustically active wildlife. La Actividad Vocal como un Índice Escalable y de Bajo Costo del Tamaño de Colonia de las Aves Marinas     

Dissipation kinetics,safety evaluation,and assessment of pre-harvest interval (PHI) and processing factor for kresoxim methyl residues in grape

A field dissipation study was conducted to evaluate the pre-harvest interval (PHI) and processing factor (PF) for kresoxim methyl (Ergon 44.3 SC) residues in grapes and during raisin making process at recommended dose (RD) and double the recommended dose (DRD). Kresoxim methyl residues dissipated following 1st-order kinetics with a half-life of 10 and 18 days at RD and DRD, respectively. The PHIs with respect to the European Union maximum residue limit (EU-MRL) of 1 mg kg^?1 for grapes were 13 and 30 days at RD and DRD, respectively. The degradation data during grape to raisin making process were best fitted to nonlinear 1st?+?1st-order kinetics with a half-life ranging between 4 and 8 days for both shade drying and with raisin dryer at different doses. The PFs were 1.19 and 1.24 with shade drying and 1.09 and 1.10 with raisin dryer, respectively, which indicates concentration of the residues during raisin making process. The dietary exposure of kresoxim methyl on each sampling day was less than the respective maximum permissible intake both at RD and DRD. The residues of kresoxim methyl in market samples of grapes and raisins were well below the EU-MRL and were also devoid of any risk of acute toxicity related to dietary exposure.     

Defining and Evaluating the Umbrella Species Concept for Conserving and Restoring Landscape Connectivity

Conserving or restoring landscape connectivity between patches of breeding habitat is a common strategy to protect threatened species from habitat fragmentation. By managing connectivity for some species, usually charismatic vertebrates, it is often assumed that these species will serve as conservation umbrellas for other species. We tested this assumption by developing a quantitative method to measure overlap in dispersal habitat of 3 threatened species—a bird (the umbrella), a butterfly, and a frog—inhabiting the same fragmented landscape. Dispersal habitat was determined with Circuitscape, which was parameterized with movement data collected for each species. Despite differences in natural history and breeding habitat, we found substantial overlap in the spatial distributions of areas important for dispersal of this suite of taxa. However, the intuitive umbrella species (the bird) did not have the highest overlap with other species in terms of the areas that supported connectivity. Nevertheless, we contend that when there are no irreconcilable differences between the dispersal habitats of species that cohabitate on the landscape, managing for umbrella species can help conserve or restore connectivity simultaneously for multiple threatened species with different habitat requirements. Definición y Evaluación del Concepto de Especie Paraguas para Conservar y Restaurar la Conectividad de Paisajes     

Some phenolic compounds of extracts obtained from Origanum species growing in Turkey

Caffeic acid, rosmarinic acid, rutin, apigenin 7-O-glucoside, apigenin, and acesetin were the main phenolic compounds of Origanum onites extracts in all applications. While acesetin contents ranged from 133.59 mg/100 g (U1) to 437.25 mg/100 g (S3), rosmarinic acid changed between 215.94 mg/100 g (U4) and 1120.56 mg/100 g (S2) in Origanum vulgare L. subsp. hirtum (Link) Ietsw. Both rosmarinic acid and acesetin were not found in U5 application. Only caffeic acid (19.39 mg/100 g) was found in U5 application. Rosmarinic acid contents of O. onites extract changed between 158.62 mg/100 g (U5) and 799.87 mg/100 g (S2). Generally, dominant phenolic compound of Origanum extracts was rosmarinic acid compared with other extracts. In addition, methanol:water:acetic acid mixture (S2) (95:4.5:0.5) was found as the best application. Phenolic contents of extracts obtained with U series mixtures were found low.     

Green synthesis of silver nanoparticles by microorganism using organic pollutant: its antimicrobial and catalytic application

A novel approach for the green synthesis of silver nanoparticles (AgNPs) from aqueous solution of AgNO₃ using culture supernatant of phenol degraded broth is reported in this work. The synthesis was observed within 10 h, and AgNPs showed characteristic surface plasmon resonance around 410 nm. Spherical nanoparticles of size less than 30 nm were observed in transmission electron microscopy. X-ray diffraction pattern corresponding to 111, 200, 220, and 311 revealed the crystalline nature of the as-formed nanoparticles. It was found that the colloidal solution of AgNP suspensions exhibited excellent stability over a wide range of ionic strength, pH, and temperature. The effect of pH and ionic strength indicated that stabilization is due to electrostatic repulsion arising from the negative charge of the conjugate proteins. The AgNPs showed highly potent antimicrobial activity against Gram-positive, Gram-negative, and fungal microorganisms. The as-prepared AgNPs showed excellent catalytic activity in reduction of 4-nitrophenol to 4-aminophenol by NaBH₄. By manufacturing magnetic alginate beads, the reusability of the AgNPs for the catalytic reaction has been demonstrated.