Human responses to social-ecological traps

Social-ecological (SE) traps refer to persistent mismatches between the responses of people, or organisms, and their social and ecological conditions that are undesirable from a sustainability perspective. Until now, the occurrence of SE traps is primarily explained from a lack of adaptive capacity; not much attention is paid to other causal factors. In our article, we address this concern by theorizing the variety of human responses to SE traps and the effect of these responses on trap dynamics. Besides (adaptive) capacities, we theorize desires, abilities and opportunities as important additional drivers to explain the diversity of human responses to traps. Using these theoretical concepts, we construct a typology of human responses to SE traps, and illustrate its empirical relevance with three cases of SE traps: Swedish Baltic Sea fishery; amaXhosa rural livelihoods; and Pamir smallholder farming. We conclude with a discussion of how attention to the diversity in human response to SE traps may inform future academic research and planned interventions to prevent or dissolve SE traps.     

Virgin ant queens mate with their own sons to avoid failure at colony foundation

Mother–son mating (oedipal mating) is practically non-existent in social Hymenoptera, as queens typically avoid inbreeding, mate only early in life and do not mate again after having begun to lay eggs. In the ant genus Cardiocondyla mating occurs among sib in the natal nests. Sex ratios are extremely female-biased and young queens face the risk of remaining without mating partners. Here, we show that virgin queens of Cardiocondyla argyrotricha produce sons from their own unfertilized eggs and later mate with them to produce female offspring from fertilized eggs. Oedipal mating may allow C. argyrotricha queens to found new colonies when no mating partners are available and thus maintains their unusual life history combining monogyny, mating in the nest, and low male production. Our result indicates that a trait that sporadically occurs in solitary haplodiploid animals may evolve also in social Hymenoptera under appropriate ecological and social conditions.     

Adenovirus and Norovirus Contaminants in Commercially Distributed Shellfish

Shellfish complying with European Regulations based on quantification of fecal bacterial indicators (FIB) are introduced into markets; however, information on viruses, more stable than FIB, is not available in the literature. To assess the presence of noroviruses (NoVs) GI and GII and human adenoviruses (HAdV) in domestic and imported mussels and clams (n = 151) their presence was analyzed during winter seasons (2004–2008) in north-west Spanish markets through a routine surveillance system. All samples tested negative for NoV GI and 13 % were positive for NoV GII. The role of HAdV as viral indicator was evaluated in 20 negative and 10 positive NoV GII samples showing an estimated sensitivity and specificity of HAdV to predict the presence of NoV GII of 100 and 74 % (cut-off 0.5). The levels of HAdV and NoVs and the efficiency of decontamination in shellfish depuration plants (SDP) were evaluated analyzing pre- and post-depurated mussels collected in May–June 2010 from three different SDP. There were no statistically significant differences in the prevalence and quantification of HAdV between pre- and post-depurated shellfish and between seawater entering and leaving the depuration systems. Moreover, infectious HAdV were detected in depurated mussels. These results confirm previous studies showing that current controls and depuration treatments limiting the number of FIB do not guarantee the absence of viruses in shellfish.     

A habitat‐based approach to predict impacts of marine protected areas on fishers

Although marine protected areas can simultaneously contribute to biodiversity conservation and fisheries management, the global network is biased toward particular ecosystem types because they have been established primarily in an ad hoc fashion. The optimization of trade‐offs between biodiversity benefits and socioeconomic values increases success of protected areas and minimizes enforcement costs in the long run, but it is often neglected in marine spatial planning (MSP). Although the acquisition of spatially explicit socioeconomic data is perceived as a costly or secondary step in MSP, it is critical to account for lost opportunities by people whose activities will be restricted, especially fishers. We developed an easily reproduced habitat‐based approach to estimate the spatial distribution of opportunity cost to fishers in data‐poor regions. We assumed the most accessible areas have higher economic and conservation values than less accessible areas and their designation as no‐take zones represents a loss of fishing opportunities. We estimated potential distribution of fishing resources from bathymetric ranges and benthic habitat distribution and the relative importance of the different resources for each port of total catches, revenues, and stakeholder perception. In our model, we combined different cost layers to produce a comprehensive cost layer so that we could evaluate of trade‐offs. Our approach directly supports conservation planning, can be applied generally, and is expected to facilitate stakeholder input and community acceptance of conservation.     

Identification of copper sources in urban surface waters using the principal component analysis based on aquatic parameters

The goal of this work was to identify the sources of copper loads in surface urban waters using principal component analysis under the aquatic parameters data evaluation approach. Water samples from the Irai and Iguacu rivers were collected monthly during a 12-month period at two points located upstream and downstream of a metropolitan region. pH, total alkalinity, dissolved chloride, total suspended solids, dissolved organic matter, total recoverable copper, temperature, and precipitation data provided some reliable information concerning the characteristics and water quality of both rivers. Principal component analysis indicated seasonal and spatial effects on copper concentration and loads in both environments. During the rainy season, non-point sources such as urban run-off are believed to be the major source of copper in both cases. In contrast, during the lower precipitation period, the discharge of raw sewage seems to be the primary source of copper to the Iguacu River, which also exhibited higher total metal concentrations.     

Corbicula fluminea gene expression modulated by CeO2 nanomaterials and salinity

Environmental Science and Pollution Research - Cerium dioxide nanomaterials (CeO2 NMs) are used in different fields and incorporated in daily products. Several studies highlighted their effects on...     

Azo-dyes photocatalytic degradation in aqueous suspension of TiO2 under solar irradiation

The photodegradation of two common and very stable azo-dyes, i.e. methyl-orange (C₁₄H₁₄N₃SO₃Na) and orange II (C₁₆H₁₁N₂SO₄Na), is reported. The photocatalytic oxidation was carried out in aqueous suspensions of polycrystalline TiO₂ irradiated by sunlight. Compound parabolic collectors, installed at the “Plataforma Solar de Almería” (PSA, Spain) were used as the photoreactors and two identical reacting systems allowed to perform photoreactivity runs for the two dyes at the same time and under the same irradiation conditions. The disappearance of colour and substrates together with the abatement of total organic carbon content was monitored. The main sulfonate-containing intermediates were found to be in lower number in respect to those obtained under artificial irradiation. In particular there were no more evidence of the presence of hydroxylated transients. The dependence of dye photooxidation rate on: (i) substrate concentration; (ii) catalyst amount; and (iii) initial pH was investigated. The influence of the presence of strong oxidant species (H₂O₂, S₂O₈²⁻) and some ions (Cl⁻, SO₄²⁻) on the process was also studied.     

Quantifying the unreported and unaccounted domestic and foreign commercial catch of sharks and rays in Western Australia

Reliable catch information is scarce for most sharks and rays worldwide, with almost half of the stocks considered to be Data Deficient due to limited species-specific catch statistics. Western Australia (WA) hosts a diverse number of shark and ray species, some of which are considered to be threatened with extinction at a global level. Commercial catch statistics only account for shark and ray landings. The present study used the best available information to reconstruct unaccounted and unreported catches for 47 shark and ray taxa to better understand the impact of fishing. For some species, there was good agreement between reconstructed catches and reported landings, but overall reconstructed catches were 57% higher than those derived from official statistics alone, underestimating the actual extraction level for many species. The reconstructed catch time series provide the basis for the assessment of all species of sharks and rays captured in WA, including protected species that interact with commercial and recreational fisheries.Supplementary informationThe online version of this article (10.1007/s13280-020-01495-6) contains supplementary material, which is available to authorised users.     

Evaluation of optimal conditions for determination of low selenium content in shellfish samples collected at Todos os Santos Bay,Bahia, Brazil using HG-AFS

This work proposes a procedure for the determination of total selenium content in shellfish after digestion of samples in block using cold finger system and detection using atomic fluorescent spectrometry coupled hydride generation (HG AFS). The optimal conditions for HG such as effect and volume of prereduction KBr 10 % (m/v) (1.0 and 2.0 ml) and concentration of hydrochloric acid (3.0 and 6.0 mol L^?1) were evaluated. The best results were obtained using 3 mL of HCl (6 mol L^?1) and 1 mL of KBr 10 % (m/v), followed by 30 min of prereduction for the volume of 1 mL of the digested sample. The precision and accuracy were assessed by the analysis of the Certified Reference Material NIST 1566b. Under the optimized conditions, the detection and quantification limits were 6.06 and 21.21 μg kg^?1, respectively. The developed method was applied to samples of shellfish (oysters, clams, and mussels) collected at Todos os Santos Bay, Bahia, Brazil. Selenium concentrations ranged from 0.23?±?0.02 to 3.70?±?0.27 mg kg^?1 for Mytella guyanensis and Anomalocardia brasiliana, respectively. The developed method proved to be accurate, precise, cheap, fast, and could be used for monitoring Se in shellfish samples.     

韶山旅游目的地形象感知研究——基于网络游记的内容分析

通过收集网络文本分析游客对旅游目的地形象的评价和感受,运用数据挖掘的手段得到游客感知目的地形象的属性与特征,已成为旅游形象研究的重要途径。本研究以携程旅行网(www.ctrip.com)上发表的韶山游记作为样本,使用Rost Content Mining内容挖掘软件得到游客感知的韶山旅游目的地形象的属性特征,运用内容分析法,建立分析类目。在此基础上,分别对建立的四个分析类目进行分析,探索游客对韶山旅游目的地形象的感知,并就游客对韶山旅游目的地形象的感知进行归纳和分析,由此,得出互联网传播的游客对韶山旅游目的地形象感知的结论。