Do the risks of predation and intermale competition affect courtship behavior in the salamander Desmognathus ochrophaeus?

Summary Natural populations of mountain dusky salamanders, Desmognathus ochrophaeus (Amphibia: Caudata: Plethodontidae), may experience two types of risk during courtship encounters: interspecific predation, affecting both sexes, and intraspecific competition for mates, affecting males. We conducted two experiments in the laboratory to determine whether and how these two risks influence the outcome of male-female encounters. In experiment 1, courtship interactions resulting in spermatophore deposition were inhibited in the presence of a restrained species of salamander (Gyrinophilus porphyriticus) known to prey on D. ochrophaeus. Probability of successful courtship was not affected by the presence of a restrained species that is not predatory (Plethodon teyahalee). In experiment 2, courtship interactions resulting in spermatophore deposition were inhibited in the presence of two restrained conspecific males, but were unaffected in the presence of a single restrained male. We conclude that the dual risks of predation and intrasexual competition for mates have been significant selective factors in shaping the evolution of courtship decisions in Desmognathus ochrophaeus. Correspondence to: P. Verrell     

Shape and efficiency of wood ant foraging networks

We measured the shape of the foraging trail networks of 11 colonies of the wood ant Formica aquilonia (Formica rufa group). We characterized these networks in terms of their degree of branching and the angles between branches, as well as in terms of their efficiency. The measured networks were compared with idealized model networks built to optimize one of two components of efficiency, total length (i.e., total amount of trail) and route factor (i.e., average distance between nest and foraging site). The analysis shows that the networks built by the ants obtain a compromise between the two modes of efficiency. These results are largely independent of the size of the network or colony size. The ants’ efficiency is comparable to that of networks built by humans but achieved without the benefit of centralized control.     

Understanding large-scale deforestation in southern Jinotega, Nicaragua from 1978 to 1999 through the examination of changes in land use and land cover

Nicaragua, home to the largest remaining extent of rainforest in Central America (total surface area) and to a significant indigenous population, has lost approximately half of its forest cover since 1950. This major and rapid loss of forest cover has been explained as the consequence of an eastward moving agricultural frontier that cuts through the region of Jinotega. If the current deforestation rate continues, the country could lose its remaining forest cover over the course of the next two decades; therefore, it is essential that the dynamics and relationships of land-use and land-cover change (LUCC) in this region are understood. To examine LUCC in Nicaragua over time, Landsat imagery from the southern portion of the region of Jinotega, taken in 1978, 1987, and 1999 was utilized. A remote-sensing method, supervised classification, which allows for the grouping of spectrally similar values for each year, followed by an image change detection analysis (postclassification comparison) was conducted. Groundtruthing (field validation) was conducted in 2006 to validate the data, which yielded increasing overall accuracy rates of 71.68% for 1978, 82.35% for 1987, and 84.38% for 1999. The classification and change detection results showed that if the agricultural cultivation overtook this region, it happened before 1978. Therefore, the possibility that either deforestation did not actually occur along an agricultural frontier or that it was located further east exists; this would be an interesting subject for future studies. There was, however, clear evidence of increased forest cover from 1987 to 1999 near the urban center, correlating with the enforced reforestation law in the city of Jinotega.     

Property rights and governance of Africa's rangelands: A policy overview

Recent efforts at securing property rights in dryland Africa have generally involved several interrelated processes such as legal and policy reforms that recognize and strengthen customary rights or the seasonal rights of pastoralists, and the decentralization of land allocation and administration to lower governance levels. These solutions are in turn beset by new problems, key among them are establishing norms for local participation in decision making, preventing manipulation and capture by elites, lack of accountability of local level institutions and authorities, and the onset of a new generation of resource user conflicts. Increasing avenues through which dialogue and communication can occur among policy actors (including local communities) in order to mobilize multiple experiences, information, and to manage power relationships — a collaborative approach to policy governance — is one way of approaching the complexity paradox. This is anticipated to provide opportunity for learning, innovation and adaptability.     

The importance of achieving a high customer satisfaction with recycling services in communities

Some studies show that there are external, infrastructural, and economic factors that enable individuals and communities to act ecologically. A variable associated with sustainable behavior is the level of satisfaction with infrastructural and economic factors, which in turn relates to recycling behavior. The main aim of this study was to assess the reliability and validity of the customer satisfaction with recycling scale and to analyze its relationship with sociodemographic variables (age and gender), house location (in the center or the suburbs, population size of), and psychological variables (self-reported individual recycling behaviors, general satisfaction with recycling service companies, and the perception of costs and the quality of service). A total of 1498 individuals responded to the in-home questionnaire related to these variables. Exploratory and confirmatory factorial analyses confirm a good fit for a four-dimensional model: assurance, tangibles, empathy, and communication. Results show that those individuals who live in town centers tend to self-report higher levels of satisfaction with tangibles than those living in the suburbs. Population sizes correlate significantly and negatively with the four dimensions of service satisfaction, while age seems to relate significantly and negatively to all the studied variables. Finally, we discuss the implications regarding the importance of customer satisfaction in facilitating the environmentally responsible behavior.     

Determination of oral uptake and biodistribution of platinum and chromium by the garden snail (Helix aspersa) employing nano-secondary ion mass-spectrometry

Environmental heavy metal contamination is a case of concern for both animal and human health. Studying the fate of metals in plant or animal tissues may provide information on pollution. In the present study, we investigated the possibility to follow the biological fate of chromium and platinum uptake in common garden snails (Helix aspersa), typically accumulating high concentrations of metals from their environment. Chromium and platinum were administered orally to snails in 5 groups (n = 25/group): control, food contaminated by ca. 2.5 μg g^?1 and 19 μg g^?1 chromium and 2.5 μg g^?1 and 25 μg g^?1 platinum, for 8 weeks. Following exposure, surviving snails were sacrificed, shell and remaining tissue investigated by ICP-MS, and shell, midgut gland and mantle by nano-secondary ion mass-spectrometry (Nano-SIMS). ¹²C¹⁴N-normalized platinum and ⁴⁰Ca-normalized chromium measurements indicated highest enrichments in cellular vesicles of the midgut gland, and lower concentrations in mantle and shell, with significantly higher platinum and chromium concentrations in the 2 exposure groups vs. control (P < 0.05), with somewhat differing distribution patterns for chromium and platinum. Comparable results were obtained by ICP-MS, with both chromium and platinum fed snails showing drastically elevated concentrations of metals in shell (up to 78 and 122 μg g^?1 dw platinum and chromium, respectively) and in other tissues (up to 200 and 1125 μg g^?1 dw platinum and chromium, respectively). Nano-SIMS allowed for semi-quantitative comparison of metal fate in snail tissues, making this an interesting technique for future studies in the area of environmental pollution.     

Higher intrinsic photocatalytic efficiency of 2,4,6-triphenylpyrylium-based photocatalysts compared to TiO2 P-25 for the degradation of 2,4-dichlorophenol using solar simulated light

The photocatalytic efficiency of two 2,4,6-triphenylpyrylium (TP(+)) based photocatalysts (supported on silica or incorporated inside zeolite Beta, 3wt%) for the degradation of 2,4-dichlorophenol (DCP) in aqueous media has been compared with TiO(2) (Degussa P-25). It was found that the efficiency of the degradation depends on the photocatalytic setup, recirculation through a tubular reactor being highly unfavorable for the TP(+)-based photocatalysts due to the deposition of the silica or zeolite particles. In contrast, high efficiency in DCP disappearance (up to 87%) and in the total organic content decrease (up to 62%) were obtained using a discontinuous batch reactor in which the TP(+) photocatalysts were uniformly suspended. Kinetic studies were also made and DCP degradation follows a first order kinetics. The obtained kinetic constants when corrected to account for the influence of the fraction of light absorbed and the amount of active sites shows that the intrinsic activity of TP(+) adsorbed on silica or incorporated inside zeolite Beta was over one order of magnitude higher than TiO(2) activity.     

Particulate matter in the indoor and outdoor air of a gymnasium and a fronton

An indoor/outdoor monitoring programme of PM₁₀ was carried out in two sports venues (a fronton and a gymnasium). Levels always below 50 μg m^?3 were obtained in the fronton and outdoor air. Due to the climbing chalk and the constant process of resuspension, concentrations above 150 μg m^?3 were registered in the gymnasium. The chalk dust contributed to CO₃ ^2? concentrations of 32?±?9.4 μg m^?3 in this sports facility, which represented, on average, 18 % of the PM₁₀ mass. Here, the carbonate levels were 128 times higher than those registered outdoors. Much lower concentrations, around 1 μg m^?3, were measured in the fronton. The chalk dust is also responsible for the high Mg²⁺ concentrations in the gym (4.7?±?0.89 μg m^?3), unfolding a PM₁₀ mass fraction of 2.7 %. Total carbon accounted for almost 30 % of PM₁₀ in both indoor spaces. Aerosol size distributions were bimodal and revealed a clear dependence on physical activities and characteristics of the sports facilities. The use of climbing chalk in the gymnasium contributed significantly to the coarse mode. The average geometric mean diameter, geometric standard deviation and total number of coarse particles were 0.77 μm, 2.79 cm^?3 and 28 cm^?3, respectively.     

The impact of social media marketing strategies on promoting sustainability of tourism with fuzzy cognitive mapping: a case of Kalanggaman Island (Philippines)

Environment, Development and Sustainability - The current literature has espoused the role of social media platforms in promoting tourism destinations. Despite such advances, limited works are...