Settled,symbiotic, then sexually mature: adaptive developmental anatomy in the deep-sea,chemosymbiotic mussel Idas modiolaeformis

The Bathymodiolinae are pervasive in reducing environments in the deep sea, yet data on post-larval and juvenile development and on the process of symbiont acquisition remain elusive. To understand how these opportunistic metazoans survive in ephemeral reducing habitats, individuals of the small bathymodiolin, Idas modiolaeformis, were examined histologically to trace their reproductive development, and with fluorescence and transmission electron microscopy to identify patterns of infection by their environmentally acquired bacterial symbionts. A size series of these mussels was retrieved from larval colonisation devices containing vegetative substrates, deployed for 51 weeks (November 2006–2007) in the central ‘Pockmarks’ region (site 2A) of the Nile deep-sea fan in the eastern Mediterranean (NDSF), a zone where methane seepage can occur (N 32° 31.97, E 30° 21.18, 1,693 m deep). Developmental patterns of germ cell migration, size at first maturity, and symbiont acquisition and localisation are presented for the post-larva to adult transition. The smallest mature adult was a male with shell length (SL) 2.35 mm. All larger individuals in the series were male (maximum SL 6.54 mm). Based on the absence of bacterial signals, plantigrades were asymbiotic, indicating strict heterotrophy in larvae and early post-larvae. During the early stages of dissoconch deposition, extracellular symbiont infection was non-specific. This was followed by increasing specificity on non-ciliated gill epithelia in adults. These observations on early development in I. modiolaeformis represent evolutionary adaptations to their ephemeral, reducing habitats.     

Effects of reduced water quality on coral reefs in and out of no‐take marine reserves

Near‐shore marine environments are increasingly subjected to reduced water quality, and their ability to withstand it is critical to their persistence. The potential role marine reserves may play in mitigating the effects of reduced water quality has received little attention. We investigated the spatial and temporal variability in live coral and macro‐algal cover and water quality during moderate and major flooding events of the Fitzroy River within the Keppel Bay region of the Great Barrier Reef Marine Park from 2007 to 2013. We used 7 years of remote sensing data on water quality and data from long‐term monitoring of coral reefs to quantify exposure of coral reefs to flood plumes. We used a distance linear model to partition the contribution of abiotic and biotic factors, including zoning, as drivers of the observed changes in coral and macro‐algae cover. Moderate flood plumes from 2007 to 2009 did not affect coral cover on reefs in the Keppel Islands, suggesting the reef has intrinsic resistance against short‐term exposure to reduced water quality. However, from 2009 to 2013, live coral cover declined by ～50% following several weeks of exposure to turbid, low salinity water from major flood plume events in 2011 and subsequent moderate events in 2012 and 2013. Although the flooding events in 2012 and 2013 were smaller than the flooding events between 2007 to 2009, the ability of the reefs to withstand these moderate floods was lost, as evidenced by a ～20% decline in coral cover between 2011 to 2013. Although zoning (no‐take reserve or fished) was identified a significant driver of coral cover, we recorded consistently lower coral cover on reserve reefs than on fished reefs throughout the study period and significantly lower cover in 2011. Our findings suggest that even reefs with an inherent resistance to reduced water quality are not able to withstand repeated disturbance events. The limitations of reserves in mitigating the effects of reduced water quality on near‐shore coral reefs underscores the importance of integrated management approaches that combine effective land‐based management with networks of no‐take reserves.     

Aspergillus sclerotiorum lipolytic activity and its application in bioremediation of high-fat dairy wastewater environments

Oils and grease (O&G) have low affinity for water and represent a class of pollutants present in the dairy industry. Enzyme-mediated bioremediation using biocatalysts, such as lipases, has shown promising potential in biotechnology, as they are versatile catalysts with high enantioselectivity and regioselectivity and easy availability, being considered a clean technology (white biotechnology). Specially in the treatment of effluents from dairy industries, these enzymes are of particular importance as they specifically hydrolyze O&G. In this context, the objective of this work is to prospect filamentous fungi with the ability to synthesize lipases for application in a high-fat dairy wastewater environment. We identified and characterized the fungal species Aspergillus sclerotiorum as a good lipase producer. Specifically, we observed highest lipolytic activity (20.72 U g⁻¹) after 96 h of fermentation using sunflower seed as substrate. The fungal solid fermented was used in the bioremediation in dairy effluent to reduce O&G. The experiment was done in kinetic from 24 to 168 h and reduced over 90% of the O&G present in the sample after 168 h. Collectively, our work demonstrated the efficiency and applicability of fungal fermented solids in bioremediation and how this process can contribute to a more sustainable wastewater pretreatment, reducing the generation of effluents produced by dairy industries.

     

Pressure Indicators of Wood Resource Use in an Atlantic Forest Area,Northeastern Brazil

Wood resources are often used to support the needs of the local population. In order to protect biodiversity and resources, conservation strategies need to consider what types of wood use have the strongest impacts on forested areas. This study aimed to identify the use categories that put higher pressure on an Atlantic forest region located in the municipality of Igarassu in Pernambuco, northeastern Brazil. To conduct the study, we measured the volume of all wood products in 62 surveyed residences and registered the average replacement time for such products. The fuelwood category was most important locally and accounted for 92% of annual wood consumption. However, the construction category harvests more destructively and concentrates on the consumption of a few wood species. Therefore we recommend the fuelwood category to be the main focus of conservation effforts. In addition, the most important species for construction purposes (e.g., Eschweilera ovata (Cambess.) Miers, Apuleia leiocarpa (Vogel) J.F. Macbr. and Pogonophora schomburgkiana Miers ex Benth) should also be considered as a priority for conservation.     

The use of nondestructive methods to assess a physiological status and conservation perspectives of <Emphasis Type="Italic">Eryngium maritimum</Emphasis> L.

Eryngium maritimum is a perennial species growing exclusively in a coastal littoral zone both on sand dunes and shingle beach and indicated as declining in Northern Europe. The objective of the present study was to prove the use of nondestructive physiological measurement methods to access physiological status of endangered plants, using E. maritimum as a model species. Plants from two Latvian sites were studied in comparison with other populations in Northern Europe (Estonia, Lithuania, Poland, United Kingdom) to find out if local differences in environmental factors affect vitality of E. maritimum individuals. Noninvasive chlorophyll analysis and chlorophyll a fluorescence measurements were used as indicators of plant physiological status through characterization of various aspects of photochemistry of photosystem II activity. Dynamics and morphology of individuals were investigated for evaluation of clonal growth potential of E. maritimum in natural conditions. Highly fluctuating trend of dynamics of individuals (within 40 groups at two Latvian sites) was established for E. maritimum in natural conditions over a five-year period. Disturbance of individuals lead to formation of new shoots from nodal root meristems. An exponential regression between fluorescence parameters F_V/F_M and Performance Index and summary monthly precipitation was found indicating that E. maritimum plants had significant tolerance to water shortage together with susceptibility to increased precipitation. Negative correlation between leaf chlorophyll content and more northern localization of individuals was found (r = 0.95 and r = 0.94, for generative and vegetative shoots, respectively). Northern populations of E. maritimum are endangered by high precipitation in conditions of low air temperature, leading to decrease of photosynthetic productivity and overall physiological status. High developmental plasticity at the root level leads to clonal growth and an efficient survival and relatively long life span of E. maritimum individuals. Chlorophyll a fluorescence is a useful method to search for the effect of suboptimal conditions on physiological status of endangered plant species without elimination and disturbance of individuals.     

Diversity and distribution of cold-seep fauna associated with different geological and environmental settings at mud volcanoes and pockmarks of the Nile Deep-Sea Fan

The Nile Deep-Sea Fan (NDSF) is located on the passive continental margin off Egypt and is characterized by the occurrence of active fluid seepage such as brine lakes, pockmarks and mud volcanoes. This study characterizes the structure of faunal assemblages of such active seepage systems of the NDSF. Benthic communities associated with reduced, sulphidic microhabitats such as sediments and carbonate crusts were sampled by remotely operated vehicles during two cruises in 2006 (BIONIL) and 2007 (MEDECO). Environmental conditions and biological factors including family-level faunal composition, density and diversity were measured at local and regional scales. Significant differences were detected at different spatial scales: (1) the fauna of reduced habitats differed substantially in activity, diversity and biomass from the non-seep environment at similar water depth, (2) cold seep microhabitats showed differences in community structure and composition related to substratum type as well as to the intensity and location of fluid emissions.