Pesticide toxicity towards microalgae increases with environmental mixture complexity

Environmental Science and Pollution Research - Effect-directed analysis (EDA) aims at identifying the compound(s) responsible for toxicity in a complex environmental sample where several dozens of...     

Synthesis and application of graphene oxide as a nanoadsorbent to remove Cd (II) and Pb (II) from water: adsorption equilibrium,kinetics, and regeneration

Environmental Science and Pollution Research - In this work, graphene oxide (GO) was synthesized by the modified Hummers method. The nanomaterial was characterized by FTIR and Raman spectroscopy,...     

Plant chemistry and insect sequestration

Most plant families are distinguished by characteristic secondary metabolites, which can function as putative defence against herbivores. However, many herbivorous insects of different orders can make use of these plant-synthesised compounds by ingesting and storing them in their body tissue or integument. Such sequestration of putatively unpalatable or toxic metabolites can enhance the insects’ own defence against enemies and may also be involved in reproductive behaviour. This review gives a comprehensive overview of all groups of secondary plant metabolites for which sequestration by insect herbivores belonging to different orders has been demonstrated. Sequestered compounds include various aromatic compounds, nitrogen-containing metabolites such as alkaloids, cyanogenic glycosides, glucosinolates and other sulphur-containing metabolites, and isoprenoids such as cardiac glycosides, cucurbitacins, iridoid glycosides and others. Sequestration of plant compounds has been investigated most in insects feeding or gathering on Apocynaceae s.l. (Apocynoideae, Asclepiaoideae), Aristolochiaceae, Asteraceae, Boraginaceae, Fabaceae and Plantaginaceae, but it also occurs for some gymnosperms and even lichens. In total, more than 250 insect species have been shown to sequester plant metabolites from at least 40 plant families. Sequestration predominates in the Coleoptera and Lepidoptera, but also occurs frequently in the orders Heteroptera, Hymenoptera, Orthoptera and Sternorrhyncha. Patterns of sequestration mechanisms for various compound classes and common or individual features occurring in different insect orders are highlighted. More research is needed to elucidate the specific transport mechanisms and the physiological processes of sequestration in various insect species.     

Assessing the extinction risk of insular,understudied marine species

Hydrothermal vents are rare deep-sea oases that house faunal assemblages with a similar density of life as coral reefs. Only approximately 600 of these hotspots are known worldwide, most only one-third of a football field in size. With advancing development of the deep-sea mining industry, there is an urgent need to protect these unique, insular ecosystems and their specialist endemic faunas. We applied the IUCN (International Union for the Conservation of Nature) Red List criteria to assess the extinction risk of vent-endemic molluscs with varying exposure to potential deep-sea mining. We assessed 31 species from three key areas under different regulatory frameworks in the Indian, West Pacific, and Southern Oceans. Three vent mollusc species were also examined as case studies of different threat contexts (protected or not from potential mining) to explore the interaction of local regulatory frameworks and IUCN Red List category assignment. We found that these assessments were robust even when there was some uncertainty in the total range of individual species, allowing assessment of species that have only recently been named and described. For vent-endemic species, regulatory changes to area-based management can have a greater impact on IUCN Red List assessment outcomes than incorporating additional data about species distributions. Our approach revealed the most useful IUCN Red List criteria for vent-endemic species: criteria B and D2. This approach, combining regulatory framework and distribution, has the potential to rapidly gauge assessment outcomes for species in insular systems worldwide.     

Perceived barriers to and drivers of community participation in protected‐area governance

Protected areas (PAs) are a frequently used conservation strategy, yet their socioeconomic impacts on local communities remain contentious. A shift toward increased participation by local communities in PA governance seeks to deliver benefits for human well‐being and biodiversity. Although participation is considered critical to the success of PAs, few researchers have investigated individuals’ decisions to participate and what this means for how local people experience the costs and benefits of conservation. We explored who participates in PA governance associations and why; the perceived benefits and costs to participation; and how costs and benefits are distributed within and between communities. Methods included 3 focus groups, 37 interviews, and 217 questionnaire surveys conducted in 3 communities and other stakeholders (e.g., employees of a nongovernmental organization and government officials) in PA governance in Madagascar. Our study design was grounded in the theory of planned behavior (TPB), the most commonly applied behavior model in social psychology. Participation in PA governance was limited by miscommunication and lack of knowledge about who could get involved and how. Respondents perceived limited benefits and high costs and uneven distribution of these within and between communities. Men, poorer households, and people in remote villages reported the highest costs. Our findings illustrate challenges related to comanagement of PAs: understanding the heterogeneous nature of communities; ensuring all households are represented in governance participation; understanding differences in the meaning of forest protection; and targeting interventions to reach households most in need to avoid elite capture.     

US Energy Conservation and Efficiency: Benefits and Costs

With increased energy conservation plus the adoption of diverse energy efficient technologies, the US economy could save about 32 quads or about 33% of its current energy consumption, if sound conservation energy use policies were implemented over approximately 10 years. This potential of 32 quads is slightly greater than the current US oil imports. The systems that have the greatest potential to provide major energy savings are transportation, residential energy use, and the food system. Not only saving energy has merit in itself, but it would save US citizens approximately $438 billion per year, helping support the US economy, a high standard of living, and energy security. In addition, this analysis suggests that reducing the $40 billion in taxpayer money spent on subsidies of the energy industries would further increase conservation.     

Early sonographic diagnosis of body stalk anomaly

Ultrasonographic features of a fetus at 18 weeks of gestation suggesting a body stalk anomaly are presented. These included a large abdominal anterior wall defect in apparent continuity with the placenta, severe kyphoscoliosis of the lower spine, the absence of one kidney, and a very short umbilical cord with only one umbilical artery. The amniotic fluid was reduced and the fetus was almost immobile at short-interval ultrasound examinations. The pregnancy was terminated and autopsy of the fetus showed abnormalities compatible with maldevelopment of both cephalic and caudal embryonic folds.     

Synergistic interactions between chemical alarm cues and the presence of conspecific and heterospecific fish shoals

Chemical and visual sources of information are used by aquatic prey during risk assessment. Here, we test the behavioral response of littoral prey fish to combinations of chemical alarm cues (skin extract) and the visual presence of a fish shoal. We scented minnow traps with either alarm cues or water (control) placed inside the trap, a jar that contained either a fish shoal or nothing (control), and recorded the number and species of fish captured. We predicted that chemical alarm cues would reduce the number of fish captured and that a fish shoal would increase the number of fish captured. The predicted effect of chemical and visual cues combined depended on the nature of the interaction. We found that the lowest catch rate was for the combination of alarm cue + no shoal, but the highest catch rate occurred for the combination of alarm cue + shoal. Fish shoal + water had the second highest catch rate and no shoal + water had the second lowest catch rate. We conclude that chemical alarm cues induce area avoidance in the absence of a shoal, but a strong behavioral proclivity to increase shoal cohesion in the presence of a shoal. The presence of a shoal in the traps induced alarmed fish to shoal with them and thus, enter the traps. This occurred even though traps were the source of the alarm cue.Communicated by A. Mathis     

The paradox of risk assessment: comparing responses of fathead minnows to capture-released and diet-released alarm cues from two different predators

Summary. Many aquatic prey are known to use chemical alarm cues to assess their risk of predation. In fishes, such alarm cues can be released either through damage of the epidermis during a predatory attack (capture-released) or through release from the predator feces (diet-released). In our study, we compared the importance of capture- versus diet-released alarm cues in risk assessment by fathead minnows (Pimephales promelas) that were na?ve to fish predators. We utilized two different fish predators: a specialized piscivore, the northern pike (Esox lucius) and a generalist predator, the brook trout (Salvelinus fontinalis). Handling time of pike consuming minnows was much shorter than for trout consuming minnows, likely resulting in less epidermal damage to the minnows during attacks by pike. In accordance with this, minnows showed a less intense antipredator response to capture-released cues from pike than capture-released cues from trout. This represents a paradox in risk assessment for the minnows as they respond to the specialized piscivore, the more dangerous predator, with a less intense antipredator response. In contrast, the minnows showed a stronger antipredator response to the specialized piscivore than to the generalist when given diet cues. This work highlights the need for researchers to carefully consider the nature of the information available to prey in risk assessment.