Variation in egg mass within two Atlantic herring Clupea harengus stocks

The main objective of this study was to investigate if egg size (mass) at spawning is invariant for Scotia-Fundy summer and autumn (SFSH) and Icelandic summer (ISSH) spawning herring Clupea harengus. Oocyte dry mass measurements for SFSH females collected in 2001 and ISSH females collected in 1999 and 2000 showed a large variation. Difference in egg dry mass among fish was found to vary by as much as twofold in each stock. For ISSH, variation in egg mass was also apparent from oocyte volume measurements made jointly with a histological examination of the ovaries. Approximately 20% of the variation in egg mass could be explained by maternal whole-body mass or total length, indicating that length or age composition in the stocks can potentially influence the recruitment success. This implies that fisheries management strategies should aim to maintain a broad range in age composition.     

Precision and accuracy of Dahl-Lea back-calculated smolt lengths from adult scales of Atlantic salmon Salmo salar

Using tagged and recaptured Atlantic salmon Salmo salar (n = 106) the present analysis shows that the most commonly applied linear back-calculation method for estimating past length, the Dahl-Lea method, resulted in overestimation of the length of large smolts and underestimation of small smolts. A correction equation (y = 0.53x + 6.23) for estimating true smolt length (y) from lengths back-calculated from adult scale measures (x) to account for these systematic discrepancies is proposed.     

Towards an urban marine ecology: characterizing the drivers,patterns and processes of marine ecosystems in coastal cities

Human population density within 100 km of the sea is approximately three times higher than the global average. People in this zone are concentrated in coastal cities that are hubs for transport and trade – which transform the marine environment. Here, we review the impacts of three interacting drivers of marine urbanization (resource exploitation, pollution pathways and ocean sprawl) and discuss key characteristics that are symptomatic of urban marine ecosystems. Current evidence suggests these systems comprise spatially heterogeneous mosaics with respect to artificial structures, pollutants and community composition, while also undergoing biotic homogenization over time. Urban marine ecosystem dynamics are often influenced by several commonly observed patterns and processes, including the loss of foundation species, changes in biodiversity and productivity, and the establishment of ruderal species, synanthropes and novel assemblages. We discuss potential urban acclimatization and adaptation among marine taxa, interactive effects of climate change and marine urbanization, and ecological engineering strategies for enhancing urban marine ecosystems. By assimilating research findings across disparate disciplines, we aim to build the groundwork for urban marine ecology – a nascent field; we also discuss research challenges and future directions for this new field as it advances and matures. Ultimately, all sides of coastal city design: architecture, urban planning and civil and municipal engineering, will need to prioritize the marine environment if negative effects of urbanization are to be minimized. In particular, planning strategies that account for the interactive effects of urban drivers and accommodate complex system dynamics could enhance the ecological and human functions of future urban marine ecosystems.     

Field performance of bacterial inoculants to alleviate water stress effects in wheat (Triticum aestivum L.)

Plant and Soil - Plant growth promoting bacteria (PGPB) containing 1-aminocyclopropane-1-carboxylate (ACC) deaminase can play an important role in abiotic stress tolerance in plants, particularly...     

Fatty acids differentiate consumers despite variation within prey fatty acid profiles

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Extensive Unexplored Human Microbiome Diversity Revealed by Over 150,000 Genomes from Metagenomes Spanning Age,Geography, and Lifestyle

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Anatomical changes with needle length are correlated with leaf structural and physiological traits across five Pinus species

The genus Pinus has wide geographical range and includes species that are the most economically valued among forest trees worldwide. Pine needle length varies greatly among species, but the effects of needle length on anatomy, function, and coordination and trade‐offs among traits are poorly understood. We examined variation in leaf morphological, anatomical, mechanical, chemical, and physiological characteristics among five southern pine species: Pinus echinata, Pinus elliottii, Pinus palustris, Pinus taeda, and Pinus virginiana. We found that increasing needle length contributed to a trade‐off between the relative fractions of support versus photosynthetic tissue (mesophyll) across species. From the shortest (7 cm) to the longest (36 cm) needles, mechanical tissue fraction increased by 50%, whereas needle dry density decreased by 21%, revealing multiple adjustments to a greater need for mechanical support in longer needles. We also found a fourfold increase in leaf hydraulic conductance over the range of needle length across species, associated with weaker upward trends in stomatal conductance and photosynthetic capacity. Our results suggest that the leaf size strongly influences their anatomical traits, which, in turn, are reflected in leaf mechanical support and physiological capacity.     

Introduced cats Felis catus eating a continental fauna: inventory and traits of Australian mammal species killed

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