Egg production and hatching success in North Adriatic Sea populations of the copepod acartia clausi

Egg production, fecal pellet production and hatching success are reported for Acartia clausi females sampled during three cruises in February 1997, 1998 and June 1997 at 20-24 stations along 4 transects in the North Adriatic Sea. Dramatically low hatching rates were recorded during both diatom bloom events in February as opposed to much higher rates during post-bloom conditions in June, even though A. clausi productivity during the bloom was apparently high. These results are discussed in the light of recent findings on the negative impact of diatoms on copepod reproductive potential.     

Assessment of herbaceous plant habitats in water-constrained environments: predicting indirect effects with fuzzy logic

Herbaceous plant production plays a key role in determining the function of rangeland ecosystems in the semi-arid and Mediterranean regions. Therefore, assessment of herbaceous plant habitats is important for understanding the ecosystem functioning in these regions and for applied purposes, such as range management and land evaluation. This paper presents a model to assess herbaceous plant habitats in a basaltic stony environment in a Mediterranean region. The model is based on geographic information systems (GIS), remote sensing and fuzzy logic, while four indirect variables, which represent major characteristics of herbaceous habitats, are modeled: rock cover fraction; wetness index (WI); soil depth; and slope orientation (aspect). A linear unmixing model was used to measure rock cover on a per pixel basis using a Landsat TM summer image. The wetness index and local aspect were determined from digital elevation data with 25 m × 25 m pixel resolution, while soil data were gathered in a field survey. The modeling approach adopted here is process-based and assumes that water availability plays a crucial role in determining herbaceous plant production in Mediterranean and semi-arid environments. The model rules are based on fuzzy logic and are written based on the hypothesized water requirements of the herbaceous vegetation. The results show that on a polygon basis there is positive agreement between the model proposed here and previous mapping of the herbaceous habitats carried out in the field using traditional methods. Intrapolygon tests show that the use of a continuous raster data model and fuzzy logic principles provide an added value to traditional mapping. Moreover, herbaceous biomass measurements at two time intervals—mid- and peak winter season—corresponded with the habitat assessment predictions achieved using a new scenario that is proposed in this research. This scenario suggests that rockiness increases herbaceous production on south-facing slopes, while in other slope aspects the rock cover has lower impact on herbaceous growth. Due to its simplicity, the model suggested here can be used by planners and managers, to adjust range activities over large areas. The process-based approach should allow adaptation of the model to other regions more effectively than models that were formulated on a purely empirical basis. The model could also be used to study the relationship between water availability and ecosystem productivity on a regional scale.     

Effects of Amazonian flying rivers on frog biodiversity and populations in the Atlantic rainforest

Given the speed at which humans are changing the climate, species with high degrees of endemism may not have time to avoid extinction through adaptation. We investigated through teleconnection analysis the origin of rainfall that determines the phylogenetic diversity of rainforest frogs and the effects of microclimate differences in shaping the morphological traits of isolated populations (which contribute to greater phylogenetic diversity and speciation). We also investigated through teleconnection analysis how deforestation in Amazonia can affect ecosystem services that are fundamental to maintaining the climate of the Atlantic rainforest biodiversity hotspot. Seasonal winds known as flying rivers carry water vapor from Amazonia to the Atlantic Forest, and the breaking of this ecosystem service could lead Atlantic Forest species to population decline and extinction in the short term. Our results suggest that the selection of morphological traits that shape Atlantic Forest frog diversity and their population dynamics are influenced by the Amazonian flying rivers. Our results also suggest that the increases of temperature anomalies in the Atlantic Ocean due to global warming and in the Amazon forest due to deforestation are already breaking this cycle and threaten the biodiversity of the Atlantic Forest hotspot.     

Zearalenone screening of human breast milk from the Naples area

The mycotoxin zearalenone exhibits estrogenic and anabolic properties in several animal species, humans included. Food contamination by zearalenone is caused either by direct contamination of grains, fruits, and their based-products or by “carry-over” of mycotoxins in animal tissues, milk, and eggs after intake of contaminated feedstuff. Now, a survey on zearalenone contamination in breast milk of healthy primiparous women living in the Naples countryside was conducted. From 47 healthy primiparous women, breast milk samples were collected within the first six weeks after delivery as well as clinical data of mother–newborn pairs. Breast milk analyses were performed with both competitive indirect enzyme-linked immunosorbent assay and high-performance liquid chromatography with fluorescence detection. At 36.9 ± 2.6 days after vaginal delivery, the mean zearalenone contents of the breast milk samples were 1.13 ± 0.34 µg/L. The zearalenone levels correlated with both mother weights before pregnancy (r = ?0.506; P < 0.001) and at delivery (r = ?0.351; P < 0.05). The present results indicate that breast milk may be contaminated with zearalenone.     

Cumulative influences of a small city and former mining activities on the sediment quality of a subtropical estuarine protected area

This study aimed to evaluate the sediment quality in the estuarine protected area known as Cananéia-Iguape-Peruíbe (CIP-PA), located on the southeastern coast of Brazil. The study was designed considering possible negative effects induced by the city of Cananéia on the sediment quality of surrounding areas. This evaluation was performed using chemical and ecotoxicological analyses. Sediments were predominantly sandy, with low CaCO₃ contents. Amounts of organic matter varied, but higher contents occurred closer to the city, as well as did Fe and Total Recoverable Oils and Greases (TROGs) concentrations. Contamination by Cd and Cu was revealed in some samples, while concentrations of Zn were considered low. Chronic toxicity was detected in all tested sediments and acute toxicity occurred only in sediments collected near the city. The principal component analysis (PCA) revealed an association among Cd, Cu, Fe, TROG, fines, organic matter, CaCO₃, and chronic toxicity, whereas acute toxicity was found to be associated with Zn and mud. However, because Zn levels were low, acute toxicity was likely due to a contaminant that was not measured. Results show that there is a broad area within the CIP-PA that is under the influence of mining activities (chronic toxicity, moderate contamination by metals), whereas poorer conditions occur closer to Cananéia (acute toxicity); thus, the urban area seems to constitute a relevant source of contaminants for the estuarine complex. These results show that contamination is already capable of producing risks for the local aquatic biota, which suggests that the CIP-PA effectiveness in protecting estuarine biota may be threatened.     

Can Eco-Labels Tune a Market? Evidence from Dolphin-Safe Labeling

In this paper we test whether the dolphin-safe labels altered consumer purchases of tuna. We also provide a partial measure of the total welfare effects of the dolphin-safe labeling policy. The results confirm our hypothesis that the dolphin–tuna controversy and the subsequent implementation of dolphin-safe labeling affected consumer behavior. Further, the paper provides market-based evidence that consumers can respond to eco-labels; the dolphin-safe label increased the market share of canned tuna. The welfare analysis provides a partial measure of society's willingness to pay to avoid personally contributing to dolphin mortality as a result of tuna fishing.     

Age effect on the antioxidant activity of Daphnia magna (Anomopoda: Daphniidae): does younger mean more sensitivity?

It has been accepted that for most species newborns and senescent organisms are more sensitive than other ages to environmental stressors. Nevertheless, it must be considered that there are several biochemical and physiological compensatory processes which are not expressed with the same magnitude during the whole life cycle. With this aim, Daphnia magna individuals of different age were exposed to hexavalent chromium, Cr (VI), at two different sublethal concentrations (0.032 and 0.0064 mg l(-1)), and the activity of some antioxidant enzymes such as catalase (CAT), superoxide dismutase (SOD), glutathione reductase (GR) and glutathione peroxidase (GPx) were evaluated during most of the life cycle of this cladoceran. The antioxidant enzymatic activity showed an inverse relationship with respect to age. The activity of CAT, GR and GPx were increased in the two treated groups, at all life stages tested. On the other hand, the activity of SOD decreased in the same groups. Both, increase and decrease in the antioxidant enzymatic activities, showed significant differences with respect to the control group, being higher for the 0.032 mg l(-1) group. The Cr (VI) LC50 was also estimated for these age groups, finding statistical differences among them. Even though adults exhibited higher responses, these enzymatic activity changes should not be interpreted as higher sensitivity, since the daphnids acute chromium toxicity followed a different pattern, with increasing LC50 values according to age.     

Complex performance of novel CoNiMnB electrodeposits in alkaline borohydride solutions

The complex performance of newly synthesized CoNiMnB electrodeposits in base-stabilized sodium borohydride solutions was examined. The rate of hydrogen generation due to borohydride hydrolysis was determined at different temperatures. Activation energy of approximately 33 kJ/mol was estimated, which is lower than the values reported for other catalysts. At electrochemical conditions, there is a competition between borohydride hydrolysis and electrooxidation reactions. The electrooxidation of borohydride takes place with low overpotentials at relatively high current densities. The long-term discharge at galvanostatic conditions as well as possibilities for partial storage of generated hydrogen indicates potentials for application of studied electrodeposits as anode material in direct borohydride fuel cells (DBFC).     

Long-Term Changes in Game Species Over a Long Period of Transformation in the Iberian Mediterranean Landscape

Agricultural change has transformed large areas of traditional farming landscapes, leading to important changes in the species community assemblages in most European countries. We suspect that the drastic changes in land-use that have occurred in Andalusia (southern Spain) over recent decades, may have affected the distribution and abundance of game species in this region. This article compares the distribution of the main game species in Andalusia during the 1960s and 1990s, using data from maps available from the Mainland Spanish Fish, Game and National Parks Service and from recent datasets on hunting yield distributions, respectively. Big-game and small-game species were significantly segregated in southern Spain during the 1990s, as two clearly independent chorotypes (groups of species whose abundances are similarly distributed) were obtained from the classification analysis. In contrast, big-game and small-game species were not significantly segregated several decades ago, when there was only one chorotype consisting of small-game species and wild boar. The other three ungulates did not constitute a significant chorotype, as they showed positive correlations with some species in the group mentioned above. These changes seem to be a consequence of the transformations that have occurred in the Iberian Mediterranean landscape over the last few decades. The abandoning of traditional activities, and the consequent formation of dense scrubland and woodland, has led to an expansion of big-game species, and a decrease of small-game species in mountain areas. Moreover, agricultural intensification has apparently depleted small-game species populations in some agricultural areas. On the other hand, the increasingly intensive hunting management could be artificially boosting this segregation between small-game and big-game species. Our results suggest that the conservation and regeneration of traditional agricultural landscapes (like those predominating in the 1960s) should be a priority for the conservation of small-game species.     

Conservation in Action: Past,Present, and Future of the National Park System of Costa Rica*

Costa Rica’s national parks stand as a model for the preservation of biodiversity in the tropics, with 622,000 ha, or 12.2%, of the country set aside in preserves. In 1970, efforts to establish the parks were met with indifference but a practical strategy for nature conservation and favorable opportunities led to success, including establishment of Poas Volcano, Cahuita, Santa Rosa and Tortuguero National Parks in 1970–1971. Since then we have concentrated on four main activities. (1) procuring funds and personnel; (2) obtaining national and international support; (3) developing conservation education programs; and (4) getting environmental legislation passed Today we continue to build the national park system. We are creating a system of national forests, encouraging commercial reforestation and management of private land, consolidating the national parks system, and continuing to raise funds. Because most tourism is based on the national parks, we are asking the tourism industry to do its fair share to support the parks and to encourage wise use and conservation. Many organizations use funds to maintain an international bureaucracy rather than supporting direct conservation in the field. We do not need more planning studies and documents to tell us what to do, but instead we need funds to make environmental conservation a reality at the grass-roots level. International environmental standards should be set by a United Nations environmental organization that is empowered to infringe on the sovereignty of individual states in environmental matters. Future concerns for the national parks of Costa Rica include the economic situation, conservation education, the need to demonstrate the monetary value of conservation, population growth, the need for citizen involvement and the need for effective environmental legislation.