Natural attenuation of residual heavy metal contamination in soils affected by the Aznalcóllar mine spill, SW Spain

Non-amended soils affected by pyritic sludge residues were monitored for 7 years to assess the long-term natural attenuation ability of these soils. The decrease in both the total concentration of elements (particularly As) and (NH(4))(2)SO(4)-extractable fractions of Mn, and Zn, below the maximum permissible levels indicate a successful natural ability to attenuate soil pollution. Soil acidification by pyrite oxidation and rainfall-enhanced leaching were the largest contributors to the reduction of metals of high (Mn, Cu, Zn and Cd) and low (Fe, Al, and As) availability. Periodic use of correlation and spatial distribution analysis was useful in monitoring elemental dispersion and soil property/element relationships.     

Trace metals and radionuclides in macroalgae from Moroccan coastal waters

Macroalgae species Codium sp, Bangia atropurpurea, Membranoptera alata, Plocamium cartilagineum, Dictyota dichotoma, Fucus spiralis and Stypocaulon scoparia were collected from seven stations along the north coast of Morocco. Samples were analysed to determine activities of naturally occurring radionuclides ((210)Pb, U isotopes and (40)K) and concentrations of metals (Zn, Fe, Co, Cu, Ni, Mn, Pb, Cd, As and Cr) using radiometric and ICP-OES techniques, respectively. Metal concentrations were within ranges reported in the scientific literature, and concentrations of bio-essential elements were in the order Mn>Fe> Zn>Cu in all samples. Brown algae had the highest concentrations of almost all metals, and concentrations decreased in the order brown>red>green algae. With respect to radionuclides, the red alga P. cartilagineum had the highest activities of (210)Pb, in most cases an order of magnitude higher than for the green alga Codium sp. (234)U and (238)U activities in all algae samples were in the range 0.96- 7.61 and 1.16-6.14 Bq/kg dry weight, respectively. Our analyses of radionuclide activities and metal concentrations in marine macroalgae showed large differences among taxa. These results provide insights into which algal species should be used for biomonitoring programmes.     

Bias in protected‐area location and its effects on long‐term aspirations of biodiversity conventions

To contribute to the aspirations of recent international biodiversity conventions, protected areas (PAs) must be strategically located and not simply established on economically marginal lands as they have in the past. With refined international commitments under the Convention on Biological Diversity to target protected areas in places of “importance to biodiversity,” perhaps they may now be. We analyzed location biases in PAs globally over historic (pre‐2004) and recent periods. Specifically, we examined whether the location of protected areas are more closely associated with high concentrations of threatened vertebrate species or with areas of low agricultural opportunity costs. We found that both old and new protected areas did not target places with high concentrations of threatened vertebrate species. Instead, they appeared to be established in locations that minimize conflict with agriculturally suitable lands. This entrenchment of past trends has substantial implications for the contributions these protected areas are making to international commitments to conserve biodiversity. If protected‐area growth from 2004 to 2014 had strategically targeted unrepresented threatened vertebrates, >30 times more species (3086 or 2553 potential vs. 85 actual new species represented) would have been protected for the same area or the same cost as the actual expansion. With the land available for conservation declining, nations must urgently focus new protection on places that provide for the conservation outcomes outlined in international treaties.     

Trophic and reproductive biochemistry of a deep-sea gelatinous octopus, Opisthoteuthis calypso

The present study provides a comprehensive analysis of the biochemical composition (proximate composition, amino acids and fatty acids in gonad, digestive gland and muscle) of the cirrate octopod, Opisthoteuthis calypso, collected off the coast of Portugal. Protein and energy contents of O. calypso were significantly lower (p < 0.05) than those observed for coastal octopods, suggesting that the gelatinous musculature of the cirrate octopus may not be a direct consequence of food limitation, but rather associated with reduced selective pressure for strong swimming ability in the deep sea. Moreover, principal component analyses of fatty acid (FA) data clearly separated coastal octopods from O. calypso. Saturated FA biomarkers (namely 16:0, 17:0, 18:0) and monounsaturated FA 22:1 suggest a higher phytodetrital influence on diet of O. calypso. A clear separation between groups was also observed with amino acid (AA) data. However, essential AA and non-essential AA designations (based on the flow of carbon through biochemical systems) do not necessarily provide an accurate picture of the origins of amino nitrogen in the deep-sea environment. Consequently, the interpretation of the present data is a challenging task but opens a new window of opportunity to unravel new trophic biomarkers in the deep sea.     

Female-female competition is influenced by forehead patch expression in pied flycatcher females

There is increasing evidence that sexual selection operates in females and not only in males. However, the function of female signals in intrasexual competition has been little studied in species with conventional sex roles. In the Iberian populations of the pied flycatcher (Ficedula hypoleuca), some females express a white forehead patch, a trait that in other European populations, only males exhibit and has become a classical example in studies of sexual selection. Here, we investigated whether the expression of this trait plays a role in female-female competition during early breeding stages. To test this hypothesis, we simulated territorial intrusions by challenging resident females with stuffed female decoys expressing or not a forehead patch. We found that resident females directed more attacks per trial and maintained closer distances to non-patched decoys than to patched ones. Also, patched females were more likely to attack the decoy than non-patched females. Interestingly, females were more aggressive against the decoys when their mate was absent. This may indicate that females relax territory vigilance in the presence of their mate or that males interfere in the interaction between competing females. The behavior of resident males was also observed, although it was not affected by decoy’s patch expression. Our findings suggest that the forehead patch plays a role in female intrasexual competition. If the forehead patch signals fighting ability, as it does in males, we may interpret that non-patched females probably avoided repeating costly agonistic encounters with the most dominant rivals.     

Biogeography of Atlantic and Mediterranean ascidians

Ascidian fauna have been intensively studied in the Atlantic Ocean, adjacent subpolar regions and Mediterranean Sea for the last 20 years. Here, we have described current species distribution patterns and identified nested areas of endemism using parsimony analysis of endemicity (PAE). We also identified diversity hotspots, areas in which species occurred exclusively, and gaps in information about distribution patterns. Finally, we compared ascidian distributions among various proposed biogeographic divisions. The comprehensive literature review provided data on the geographic distribution of 627 species of ascidians. In the West Atlantic, there were three peaks in richness: north Caribbean—96 species, São Paulo and Rio de Janeiro—61 species and the subantarctic region—54 species. In the eastern Atlantic, the greatest richness occurred on Spanish and French coasts—91 species and in Senegal—83 species. In the Mediterranean, the greatest richness was in Spain and France—142 species and Italy—127 species. PAE designated 20 areas of endemism nested within eight larger regions that were more or less in agreement with realms or provinces of previous studies: North Atlantic, Caribbean, southeastern Brazil, Magellanic, Subantarctic, Tropical West Africa, South Africa, and Mediterranean. Distribution patterns of the Ascidiacea, in general, followed previously proposed divisions of regions and provinces in the Atlantic and adjacent polar regions, but not subdivisions of these regions.     

Sulfur, chromium, and selenium accumulated in Chinese cabbage under direct covers

Currently, pollution of our agricultural soils and waters is increasing and is often associated with many human health ailments. Soils contaminated with low levels of heavy metals and other trace elements are frequently used for growing vegetable crops and in such a situation, these toxic contaminants often accumulate in the edible portions of these agricultural plants and thereby enter the human food chain. In 3 consecutive years of field experiments (1994-1996), two different crop-covering treatments--T (50 microm perforated polyethylene), and T2 (17 gm(-2) non-woven polypropylene)--were used to modify the environmental conditions for the growth of Chinese cabbage 'Nagaoka 50' [Brassica rapa L. (Pekinensis group)]. Open-air plots (T(0)) were used as controls. Analytical determinations of chromium (Cr), selenium (Se), two forms of sulfur (total-S and sulfate-S), and amino acids (Isoleucine, leucine, lysine, methionine, serine, threonine, and valine) were performed utilizing plant shoots for analysis. The T1 and T2 treated plants contained concentrations of lysine, methionine, serine, and threonine higher than in T(0). Under T1, the extent of Cr and Se removal in the field was more favorable. Direct covers could be used in contaminated agricultural zones for a variety of plant species, not just for use with those plants previously reported to be efficient at bio-accumulating toxic elements because the thermal effect created by the covers favors phytoextraction processes. However, it is clear that the accumulation of these toxic substances in the plants (Cr) would deem the plant material unsuitable for human consumption and use as animal fodder.     

Soil quality alteration by mouldboard ploughing in a commercial farm devoted to no-tillage under Mediterranean conditions

In semi-arid Mediterranean areas, studies about conservation tillage (CT) systems have demonstrated advantages in crop yield, soil water storage and soil protection. However, the benefits observed with CT in trials with experimental plots (normally of small dimensions) might not be so clear in large commercial farms. In many areas of SW Spain, farmers often do an occasional tillage with mouldboard ploughing (MP) to avoid potential compaction problems and to encourage the emergence of seedlings. The present study deals with the effect of the application of MP on soil quality: total organic carbon, water soluble carbon, active carbon, microbial biomass carbon, dehydrogenase, β-glucosidase and o-diphenol oxidase activities and crop development (wheat) in a commercial farm devoted to no-tillage (NT) since 1995. In 2006, MP was applied on a band of the soil, while the rest was left under the strict conservation system. The direct and residual effects of MP in the two subsequent years were evaluated. In the first year MP caused a decrease in soil quality that persisted in the following two years. Emergence, nutrient accumulation, nutrient efficiency ratios and yield of wheat were slightly enhanced by MP in the first year. However, this trend was the opposite in the two subsequent years. Although in other scenarios traditional tillage has been applied to avoid soil compaction and to increase crop yield, under our experimental conditions the occasional mouldboard ploughing application was not justified.