Pan-European regional-scale modelling of water and N efficiencies of rapeseed cultivation for biodiesel production

The energy produced from the investment in biofuel crops needs to account for the environmental impacts on soil, water, climate change and ecosystem services. A regionalized approach is needed to evaluate the environmental costs of large-scale biofuel production. We present a regional pan-European simulation of rapeseed ( Brassica napus ) cultivation. Rapeseed is the European Union's dominant biofuel crop with a share of about 80% of the feedstock. To improve the assessment of the environmental impact of this biodiesel production, we performed a pan-European simulation of rapeseed cultivation at a 10 × 10 km scale with Environmental Policy Integrated Climate (EPIC). The model runs with a daily time step and model input consists of spatialized meteorological measurements, and topographic, soil, land use, and farm management practices data and information. Default EPIC model parameters were calibrated based on literature. Modelled rapeseed yields were satisfactory compared with yields at regional level reported for 151 regions obtained for the period from 1995 to 2003 for 27 European Union member countries, along with consistent modelled and reported yield responses to precipitation, radiation and vapour pressure deficit at regional level. The model is currently set up so that plant nutrient stress is not occurring. Total fertilizer consumption at country level was compared with IFA/FAO data. This approach allows us to evaluate environmental pressures and efficiencies arising from and associated with rapeseed cultivation to further complete the environmental balance of biofuel production and consumption.     

Molecular evidence of cycad seed predation by immature Aulacoscelidinae (Coleoptera: Orsodacnidae)

Adult beetles in the small subfamily Aulacoscelidinae (superfamily Chrysomeloidea) are known to feed on the foliage and juices of New World cycads (Order Cycadales; family Zamiaceae), but the habits of larvae have long remained a mystery. We provide the first direct evidence that Aulacoscelidinae larvae feed on and develop within the megagametophyte of the Mesoamerican cycad, Dioon merolae (Zamiaceae). Phylogenetic analyses based on partial DNA sequences from 3 genes recover a cycad seed‐feeding larva proposed to belong to Aulacoscelidinae. These observations reveal a more intimate feeding relationship between Aulacoscelidinae and their New World cycad host plants than was previously recognized. Further, adult Aulacoscelidinae have long been noted to resemble Jurassic fossil chrysomeloids in the extinct subfamily Protoscelidinae. The molecular, morphological, ecological and fossil data reported herein are broadly compatible with an early association between Aulacoscelidinae and their gymnosperm hosts.     

Leaf Thickness and Water Deficit in Plants: A Tool for Field Studies

B?rquez, A. 1987. Leaf thickness and water deficit in plants:a tool for field studies.—J. exp. Bot. 38: 109–114. A technique for estimating plant water deficits using a relativelyinexpensive micrometer to measure leaf thickness was developed.A strong correlation was found between leaf thickness and relativewater content (RWC) in Brassica napus, Mirabilis jalapa, Phaseolusvulgaris and Impatiens parviflora. Although leaf thickness ata given RWC varied between plants, it increased linearly withleaf RWC, the rate of change being similar in leaves of plantsof the same age and species. Due to this relationship, the constructionof a pressure-volume curve makes possible the estimation ofleaf water potential. In this case a calibration curve is neededfor each population studied or, for the highest accuracy, foreach individual. The technique is particularly useful in fieldconditions where other techniques are not reliable because ofdifficulties in controlling temperature and where non-destructivemeasurements are required. Key words: Leaf thickness, relative water content, water potential     

Environmental and geographical determinants of beta diversity of leaf beetles (Coleoptera: Chrysomelidae) in the Iberian Peninsula

Abstract.  1. The effect and relative importance of both environmental and geographic factors on species turnover of Chrysomelidae assemblages in the Iberian Peninsula was explored.
2. Ordination and classification analysis of species lists from well-sampled local areas identified two main biogegraphic groups of inventories, discriminating between Eurosiberian and Mediterranean faunas.
3. After describing this pattern, the underlying determinants were explored, separating pure from combined effects of environment and geography by means of partial canonical correspondence analysis.
4. Results indicate that pure effects of environment and geographic position are of similar magnitude (about 20% of the variation from each), and quite important in comparison with combined effects.
5. The power of the pure effect of geographical variables, together with beta-diversity independence of species richness gradients, point to the inadequacy of environmental measurement explanation of beta-diversity patterns, and to the existence of a major component of geographical variation independent of environment.     

Preliminary assessment of the use of electron backscatter diffraction (EBSD) in conodonts

Pérez‐Huerta, A., Cusack, M. & Méndez, C.A. 2011: Preliminary assessment of the use of electron backscatter diffraction (EBSD) in conodonts. Lethaia, Vol. 45, pp. 253–258. Conodonts are extensively used as ‘geochemical tools’ in palaeoenvironmental reconstructions in Palaeozoic and Triassic strata. The retention of a primary geochemical signal is substantially dependent on the ultrastructural integrity and crystallinity after diagenesis. Direct assessments of the preservation potential of the polycrystalline matrix are scarce with the exception of the application of transmission electron microscopy (TEM). The possible application of electron backscatter diffraction (EBSD) is introduced for well‐preserved Pennsylvanian platform conodont elements as a novel in situ technique based on successful previous results for biogenic carbonates. EBSD shows the presence of no diffraction in central regions of all studied elements of Idiognathodus and Adetognathus, with possible implications for geochemistry analysis. The absence of diffraction could be attributed to the existence of an amorphous phase, water (+OH) or a process of hypocalcification related to the development of ‘growth cavities’ in the lamellar crown tissue. Overall results indicate the suitability of using EBSD to extract crystallographic information from conodonts and potentially for other apatite (micro‐) fossils. □Conodont, diagenesis, EBSD, geochemistry, Pennsylvanian.     

Multiple mating increases cocoon hatching success in the earthworm Eisenia andrei (Oligochaeta: Lumbricidae)

In simultaneous hermaphrodites with reciprocal mating, multiple mating may be a male strategy that conflicts with female interests, and therefore an intra‐individual sexual conflict regarding the number of matings may be expected. The evolutionary outcome of this sexual conflict will depend on the costs and benefits that extra mating entails for each sexual function. In the present study, we investigated the costs and benefits of multiple mating on cocoon number, cocoon mass, and cocoon hatching success in the redworm Eisenia andrei, a simultaneous hermaphrodite with reciprocal insemination, by manipulating the number of matings with different partners. We did not detect any reduction in the female reproductive output (number and mass of cocoons) with increasing number of mating partners. However, we found that multiple mating showed benefits for female reproduction that increased the hatching success of the cocoons. This effect may be a result of increased quantity and/or diversity of sperm in the spermathecae of multiple mated earthworms. Further studies are required to clarify the mechanism underlying the increased cocoon hatching success when redworms engage in multiple matings. © 2012 The Linnean Society of London, Biological Journal of the Linnean Society, 2012, ?? , ??–??.     

Innate aversion to ants (Hymenoptera: Formicidae) and ant mimics: experimental findings from mantises (Mantodea)

Field data suggest that ants may be important predators of mantises which, in turn, may be important predators of jumping spiders (Salticidae). Using a tropical fauna from the Philippines as a case study, the reactions of mantises to ants, myrmecomorphic salticids (i.e. jumping spiders that resemble ants) and ordinary salticids (i.e. jumping spiders that do not resemble ants) were investigated in the laboratory. Three mantis species ( Loxomantis sp., Orthodera sp., and Statilia sp.) were tested with ten ant species, five species of Myrmarachne (i.e. myrmecomorphic salticids), and 23 ordinary salticid species. Two categories of the myrmecomorphic salticids were recognized: (1) 'typical Myrmarachne ' (four species with a strong resemblance to ants) and (2) Myrmarachne bakeri (a species with less strong resemblance to ants). Ants readily killed mantises in the laboratory, confirming that, for the mantises studied, ants are dangerous. In alternate-day testing, the mantises routinely preyed on the ordinary salticids, but avoided ants. The mantises reacted to myrmecomorphic salticids similarly to how they reacted to ants (i.e. myrmecomorphic salticids appear to be, for mantises, Batesian mimics of ants). Although myrmecomorphic salticids were rarely eaten, M . bakeri was eaten more often than typical Myrmarachne . Because the mantises had no prior experience with ants, ant mimics or ordinary salticids, our findings suggest that mantises have an innate aversion to attacking ants and that this aversion is generalized to myrmecomorphic salticids even in the absence of prior experience with ants. © 2006 The Linnean Society of London, Biological Journal of the Linnean Society , 2006, 88 , 23–32.