Meta-analysis of the differential effects of habitat fragmentation and degradation on plant genetic diversity

Genetic diversity is a key factor for population survival and evolution. However, anthropogenic habitat disturbance can erode it, making populations more prone to extinction. Aiming to assess the global effects of habitat disturbance on plant genetic variation, we conducted a meta-analysis based on 92 case studies obtained from published literature. We compared the effects of habitat fragmentation and degradation on plant allelic richness and gene diversity (equivalent to expected heterozygosity) and tested whether such changes are sensitive to different life-forms, life spans, mating systems, and commonness. Anthropogenic disturbance had a negative effect on allelic richness, but not on gene diversity. Habitat fragmentation had a negative effect on genetic variation, whereas habitat degradation had no effect. When we examined the individual effects in fragmented habitats, allelic richness and gene diversity decreased, but this decrease was strongly dependent on certain plant traits. Specifically, common long-lived trees and self-incompatible species were more susceptible to allelic richness loss. Conversely, gene diversity decreased in common short-lived species (herbs) with self-compatible reproduction. In a wider geographical context, tropical plant communities were more sensitive to allelic richness loss, whereas temperate plant communities were more sensitive to gene diversity loss. Our synthesis showed complex responses to habitat disturbance among plant species. In many cases, the absence of effects could be the result of the time elapsed since the disturbance event or reproductive systems favoring self-pollination, but attention must be paid to those plant species that are more susceptible to losing genetic diversity, and appropriate conservation should be actions taken.     

Effects of amusing memes on concern for unappealing species

There is limited knowledge of the mechanisms that can inspire people's concern and engagement in the protection of unpopular and unappealing species. We analyzed Polish people's interest in themed internet memes featuring the proboscis monkey (Nasalis larvatus) and the consequences of this interest for conservation marketing. We examined Google Trends data, used Google Search, and searched popular media materials to estimate interest in the proboscis monkey in Poland. Photos of the proboscis monkey when presented with humor in internet memes attracted as much interest as usually more popular species (e.g., koala, panda, and orangutan) used in marketing by nongovernmental organizations. Amusing internet memes spread by social media positively correlated with increasing interest in the unappealing species, such as proboscis monkey. Interest in amusing internet memes positively correlated with individuals’ decisions to donate to 6 crowdfunding actions. Thus, conservation marketing that includes amusing memes and social media may provide a worthwhile complement to traditional campaigns and are likely to influence individuals who are unaffected by the usual means.     

The use of nanovermiculite catalyst in the study of removal of the organic load and degradation of atrazine via ozone process in RPB reactor

Abstract

The main objective of this study is the degradation of a synthetic solution of atrazine by a modified vermiculite catalyzed ozonation, in a rotating packed bed (RPB) reactor. A 0.5?L RPB reactor was used to perform the experiments, using a Central Composite Design (CCD) response surface to construct the quadratic model based on the factors: pH, catalyst concentration and reactor rotation frequency. The response variable was the removal of the organic load measured in terms of Chemical Oxygen Demand (COD). After the complete quadratic model was constructed through the response surface, the COD degradation process had an optimal removal of 41% under the following conditions: pH 8.0, rotation of 1150?rpm and catalyst concentration 0.66?g L^?1.     

Decreased blood level of β2-microglobulin in the employees of a factory which produced polychlorinated biphenyls

Under the project of evaluating the health status of the employees of CHEMKO factory (East Slovakia) which produced PCBs between 1955 and 1985, the level of β₂-microglobulin (β₂-m) was measured in the serum of 242 subjects from CHEMKO (Group A) and two control groups from much less polluted areas: 1. 277 females from a small mountainous village (Group B), 2. 179 adults from the area of a large city of Ko ice (Group C). The level of thymidine kinase (TK) was measured in the groups A and B only. In addition, age-matched groups of 155 women each from all areas were evaluated. In both the whole group and the age-matched group from CHEMKO the level of β₂-m was significantly lower (P<0.001) than that in the respective control groups, while no difference was found in the level of TK. In conclusion, it is suggested that the decrease of β₂-m in CHEMKO employees might be related to the immunotoxic effects of organochlorines.     

Metal accumulation in sediments and benthic invertebrates in lakes of Latvia

The concentrations of cadmium, lead, nickel and copper in waters, sediments (total metal concentrations and their speciation forms) and benthic macroinvertebrates in 11 lakes of Latvia were determined using atomic absorption spectroscopy. Metal concentrations in lake waters, sediments and biota were compared with water chemistry. Compared to total concentrations, metal speciation forms in sediments were better correlated with respective metal concentrations in invertebrates. Therefore, the evaluation of potential metal bioaccumulation should consider metal speciation. The mean concentrations of trace metals in benthic invertebrates in Latvia were much lower than in other countries, which can be explained by comparatively lower anthropogenic loads. However, local areas of anthropogenic impacts were evident.     

Natural phillipsite as a matrix for a slow-release formulation of oxamyl

The performance of phillipsite as a matrix for slow-release formulation of oxamyl [N,N-dimethyl-2-methylcarbamoyl-oxymino-2-(methylthio)acetamide] was tested. The adsorption kinetics followed a first-order law, and the adsorption isotherm fitted well in a two-surface Langmuir model, suggesting a double mechanism of interaction between oxamyl and the sorbent. The sorption mechanism, studied by FTIR, provided two fractions of oxamyl. The first one is sorbed on the mineral surface, linked by H-bonding, and the second one is constituted by a multilayer of oxamyl molecules linked by a water bridge between them. The release kinetics of oxamyl from a substratum zeolite-oxamyl also follows a first-order law, with two stages that correspond to both fractions of oxamyl previously detected.     

The effect of pH on zinc adsorption equilibria and exchangeable zinc pools in soils

Zinc adsorption equilibria were measured in soils differing in pH but with similar textures and total zinc concentrations, using adsorption isotherm and isotopic exchange techniques. The results suggested that the equilibrium between solution and exchangeable zinc was strongly pH dependent and the active zinc species in adsorption was single charged (e.g. Zn(OH)(+)). The size of the exchangeable zinc pool was not strongly pH dependent. Similar results were obtained when zinc was added to the soils, either as Zn(NO(3))(2) or in sewage sludge.     

The combined use of chemical and biochemical markers to assess water quality along the Ebro River

Carp (Cyprinus carpio) and barbel (Barbus graellsii) were collected from five sites along the Ebro River. The study was designed to assess levels of persistent organic pollutants and metals bioaccumulated by fish, and some biochemical responses (cytochrome P450 system, phase II activities, and metallothioneins) against those pollutants. The highest levels of PCBs and DDTs were detected in carp from industrialised areas, which also showed high levels of mercury and cadmium in the liver, and high levels of nonylphenol in bile. Significant alterations in some biochemical markers were observed and associated to combined exposure to pollutants. The activity 7-ethoxyresorufin O-deethylase ranged from 69 pmol/min/mg protein in carp from the reference site to 415 pmol/min/mg protein in those from polluted sites. Carp from the Ebro Delta, an agricultural area, had depressed acetylcholinesterase in muscle tissue. Metallothionein concentrations were positively correlated with copper residues, but no significant differences among sampling points were observed.     

Effect of chromium on the fatty acid composition of two strains of Euglena gracilis

The effect of hexavalent chromium on fatty acid composition was studied in two strains of Euglena gracilis; UTEX 753 (from the Culture Collection of Algae of Texas University, USA) and MAT (isolated from a highly polluted River). Both were grown in photoauxotrophic and photoheterotrophic conditions and exposed to two metal concentrations, one below and one above IC50. The high malondialdehyde (MDA) levels (3 to 7-fold) obtained with chromium concentration above IC50, suggested the existence of metal-induced lipid peroxidation. Total lipid content increased only with concentration below IC50, whereas it was inhibited by higher metal concentration. Photoheterotrophic control strains exhibited a significantly higher proportion of saturated and polyunsaturated fatty acids. Polyunsaturated acids were most affected by chromium, especially those related to chloroplast structures. Ultra-structure studies showed clear thylakoid disorganization in all treated cells. The results indicate that hexavalent chromium affects levels of fatty acids, especially those related to photosynthetic activity.