Transboundary Socio-Ecological Effects of a Marine Protected Area in the Southwest Atlantic

Marine Protected Areas (MPAs) have been regarded as an alternative to protect natural resources and to improve fisheries. However, MPAs may also have negative socio-economic consequences on fishing communities. We aimed to check the effectiveness of a socially conflicting MPA in Brazil by assessing target reef fish biomass in islands inside (n = 6) and outside (n = 6) the MPA, fisheries’ productivity (biomass), catch per unit of effort (CPUE), and fishers’ socio-economic status (mainly fishers’ income) in three fishing communities subjected to different degrees of influence (close, average, and long distance) of the MPA. The CPUE was higher in the fishing community that was further away from the MPA, fish biomass was higher in the islands located inside the MPA in the southern region and in the islands located outside the MPA in the northern region, while fishers were making the most money closest to the MPA, where conflicts are the highest, probably from practicing very intensive fisheries. This integrated approach showed that the studied MPA has not delivered ecological benefits, such as higher CPUE or more fish, while higher income closer to the MPA could not be clearly attributed to its effects.     

Ozone uptake by citrus trees exposed to a range of ozone concentrations

The Citrus genus includes a large number of species and varieties widely cultivated in the Central Valley of California and in many other countries having similar Mediterranean climates. In the summer, orchards in California experience high levels of tropospheric ozone, formed by reactions of volatile organic compounds (VOC) with oxides of nitrogen (NO_x). Citrus trees may improve air quality in the orchard environment by taking up ozone through stomatal and non-stomatal mechanisms, but they may ultimately be detrimental to regional air quality by emitting biogenic VOC (BVOC) that oxidize to form ozone and secondary organic aerosol downwind of the site of emission. BVOC also play a key role in removing ozone through gas-phase chemical reactions in the intercellular spaces of the leaves and in ambient air outside the plants. Ozone is known to oxidize leaf tissues after entering stomata, resulting in decreased carbon assimilation and crop yield. To characterize ozone deposition and BVOC emissions for lemon (Citrus limon), mandarin (Citrus reticulata), and orange (Citrus sinensis), we designed branch enclosures that allowed direct measurement of fluxes under different physiological conditions in a controlled greenhouse environment. Average ozone uptake was up to 11 nmol s^?1 m^?2 of leaf. At low concentrations of ozone (40 ppb), measured ozone deposition was higher than expected ozone deposition modeled on the basis of stomatal aperture and ozone concentration. Our results were in better agreement with modeled values when we included non-stomatal ozone loss by reaction with gas-phase BVOC emitted from the citrus plants. At high ozone concentrations (160 ppb), the measured ozone deposition was lower than modeled, and we speculate that this indicates ozone accumulation in the leaf mesophyll.     

Volatile organic compounds from Italian vegetation and their interaction with ozone

Volatile Organic Compounds (VOCs) emitted from vegetation (particularly isoprenoids) represent an important source of atmospheric hydrocarbons almost double the anthropogenic source. When biogenic VOC mix with NO_x in the presence of UV radiation, ozone (O₃) is formed. In Italy, optimal conditions for O₃ formation in terms of VOC/NO_x ratios and abundance of UV radiation occur for long periods of the year. Moreover, Italian vegetation includes several species that are strong and evergreen isoprenoid emitters, and high temperatures for part of the year further stimulate these temperature-dependent emissions. We review emission of isoprenoids from Italian vegetation, current knowledge on the impact of rising O₃ levels on isoprenoid emission, and evidence showing that isoprenoids can increase both the O₃ flux to the plant and protection against oxidative stress because of their antioxidant functions. This trait not only influences plant tolerance to O₃ but also may substantially alter the flux of O₃ between atmosphere and biosphere.     

Occurrence of organochlorine pesticides (OCPs) and their enantiomeric signatures, and concentrations of polybrominated diphenyl ethers (PBDEs) in the Adélie penguin food web, Antarctica

Concentrations and enantiomeric signatures of organochlorine pesticides were determined in Antarctic krill, emerald rockcod and Adélie penguin from the Ross Sea, Antarctica. HCB and DDTs were prevalent contaminants in penguin eggs. The highest concentrations of SigmaHCHs (1.35 +/- 0.72 ng/g) were found in the rockcod muscle, where gamma-HCH (1.23 +/- 0.67 ng/g) was the principal isomer. The ratio gamma-HCH/alpha-HCH was evaluated. Enantioselective gas chromatography was used for the evaluation of enantiomeric fractions (EFs) for alpha-HCH and oxychlordane. An increase of 14% in the (+)alpha-HCH enantiomer was found from krill through penguin, suggesting the enantioselective biotransformation increased proportionately with trophic level. Polybrominated diphenyl ethers (PBDEs) were measured and their concentrations were 5.6 +/- 1.12, 5.81 +/- 2.32, 4.57 +/- 0.17 and 3.06 +/- 3.27 ng/g lipids in krill, rockcod muscle, rockcod homogenate and penguin eggs, respectively. The detection of BDE28, BDE47, BDE99 and BDE100 in Antarctic organisms confirmed their global transport and distribution; the detection of lower brominated congeners suggested a potential long-range transport.     

Mutagenicity and organic halogen determination in body fluids and tissues of rats treated with drinking water and pulp mill bleachery effluent concentrates

Concentrates of either drinking water or chlorination stage pulp mill effluent were injected intraperitonally into rats. Urine, feces, liver, and adipose tissues were tested for mutagenic activity and analysed for organic halogen. For both sample types nearly all the organic halogen taken up, eighteen percent from the chlorination stage sample and four percent from the drinking water sample, was excreted via the urine during the first day. Weak mutagenic activity could only be found in the urine collected the first day from animals treated with the highest dose of drinking water.     

Competition for the home and aggressive behaviour in the chiton Acanthopleura gemmata (Blainville) (Mollusca: Polyplacophora)

Summary Computerized screening of all the positions recorded during a synodic month on 120 individually marked chitons (Acanthopleura gemmata) pinpointed their preferential resting points. Unlike the majority of intertidal chitons so far studied, A. gemmata rests in well-defined homes actively dug in the rock. Homes proved to be not strictly individual and periodically interchangeable. A complex aggressive behaviour was recorded in the field when two animals came in contact at home. When competing for ownership of a resting site rival chitons may suppress their nocturnal feeding activity. Despite its strong home-related territoriality A. gemmata showed no mutual exclusion on the feeding area. The highly specialized resting habits clearly protects A. gemmata from its most important predator, the toad fish Arothron immaculatus. The behaviour of A. gemmata is compared to that of other chitons and gastropods, and the current hypotheses concerning the adaptive value of the homing behaviour in littoral molluscs are discussed.     

Long term monitoring of pollutants in eggs of Yellow-legged Herring Gull from Capraia island (Tuscan Archipelago)

Chlorinated hydrocarbons (hexachlorobenzene, lindane, ppDDE, polychlorinated biphenyls) and trace elements (Hg, Se, Cd, Pb) were determined in eggs of Yellow-legged Herring Gull (Larus cachinnans) collected in an island of the Tyrrhenian Sea during the period 1981–1986. PCBs levels vary on the average between 30.4g g^–1 d.w. in 1981 to 56.1 g g^–1 d.w. in 1983. The capillary chromatograms revealed the presence of about 30 somers of PCBs without significant variations in the eggs of the same year; more than 50% of the residues is made up only three isomers: the 22'44'55', the 22'344'5' and the 22'344'55'. Average DDE residues were 7–8 times lower than those of PCBs and declined during the period (from 9.2 g g^–1 d.w. in 1981 to 4.5 g g^–1 d.w. in 1986). Cadmium and lead are present in low concentrations. The average levels of mercury and selenium are around 2–2.5 g g^–1 d.w., and a cumulative correlation, on a molar basis, exists between these two elements.     

Sister chromatid exchanges in first-trimester chorionic villi after in vivo and in vitro exposure to diagnostic ultrasound

A study was done to evaluate the effects of diagnostic ultrasound on sister chromatid exchange (SCE) in first-trimester chorionic villi under controlled technical conditions. Chromosome analysis was performed by the direct method using spontaneous mitoses from the cytotrophoblast layer, and SCE visualization was accomplished by a 72 h treatment with 5-bromodeoxyuridine (BrdU) at a concentration of 10μg/ml. The slides were stained with ac ridine orange. Immediately before first-trimester chorionic villus sampling, a group of ten pregnant women was exposed to diagnostic ultrasound for 20min (in vivo exposure). This group of patients was compared with a control group who were not exposed. A mean value of SCE/cell frequency of 4·2 ± 0·2 was found in the exposed pregnancies, while a value of 3·7 ± 0·2 was observed in the control group. After in vitro exposure of chorionic villi obtained from elective abortions, the frequency of SCE/cell did not differ significantly among samples with different exposures (1,2, and 3 h) and controls. The positive control (mitomycin C) yielded a significant increase in SCE frequency.     

意大利的金枪鱼、箭鱼、鸬鹚以及家燕等体内的多氯萘、多氯联苯、多氯二苯-p-二恶英、多氯二苯并呋喃以及p,p''''-DDE

我们曾对从意大利收集的金枪鱼、箭鱼、普通鸬鹚以及家燕体内的p,p'-DDE、多氯联苯同类物(PCBs)、多氯二苯-p-二恶英(PCDDs)、多氯二苯并呋喃(PCDFs)以及多氯萘(PCNs)浓度进行过测量.