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Industrial-scale fisheries are often thought to reduce food availability for top predators. It is essential to estimate the spatial and temporal overlap over a fine scale between fisheries and pre- dators during their breeding season, when their energy demand is greatest and when they are most spatially constrained, in order to understand and manage this potential impact on their populations. In the Benguela upwelling region, 2 endemic vulnerable seabirds, Cape gannets Morus capensis and African penguins Spheniscus demersus, mainly eat anchovy Engraulis encrasicolus and sardine Sardinops sagax, both of which are exploited by the purse-seine fishery. A recent eastward displace- ment of small pelagic fish off the South African coast has reduced fish availability for both birds and fisheries along the west coast. Using GPS-recorders, we studied the foraging dispersal of birds from 8 colonies containing 95% of the global Cape gannet and 60% of the global African penguin popu- lations to assess their overlap with fish catches. Despite the fact that bird data were gathered at very fine spatial and temporal scales (meters and hours), and fisheries data were recorded at much coarser spatial and temporal scales (20 km and months), there was clear overlap in areas used. The main for- aging areas of both species were located where purse-seine fisheries caught most fish, with most catches occurring during the birds' breeding season. As birds and fisheries also overlap in the size of the targeted prey and the depth of exploitation, our study suggests the potential for intense competi- tion between purse-seine fisheries and decreasing seabird populations in the southern Benguela. Long-term protection of these seabird species requires the inclusion of a suitable ecological buffer when setting fishery quotas, and implementing marine protected areas closed to fishing around key breeding sites and foraging hotspots may improve their breeding success.

Animal aggregation is a general phenomenon in ecological systems. Aggregations are generally considered as an evolutionary advantageous state in which members derive the benefits of mate choice and protection against natural enemies, balanced by the costs of limiting resources and intraspecific competition. Many insects use chemical information to find conspecifics and to form aggregations. In this study, we describe a spatio-temporal simulation model designed to explore and quantify the effects of the strength of chemical attraction, on the colonization ability of a fruit fly (Drosophila melanogaster) population. We found that the use of infochemicals is crucial for colonizing an area. Fruit flies subject to an Allee effect that are unable to respond to chemical information could not successfully colonize the area and went extinct within four generations. This was mainly caused by very high mortality due to the Allee effect. Even when the Allee effect did not play a role, the random dispersing population had more difficulties in colonizing the area and is doomed to extinction in the long run. When fruit flies had the ability to respond to chemical information, they successfully colonized the orchard. This happened faster, for stronger attraction to chemical information. In addition, more fruit flies were able to find the resources and the settlement on the resources was much higher. This resulted in a reduced mortality due to the Allee effect for fruit flies able to respond to chemical information. Odor-mediated aggregation thus enhances the colonization ability of D. melanogaster. Even a weak attraction to chemical information paved the way to successfully colonize the orchard.

Gully erosion is considered to be one of the most important soil erosion processes, but its contribution to soil loss is still discussed. Despite the efforts made to understand the occurrence and dynamics of gullies, there is still a lack of knowledge on the factors leading to gully formation and growth. Within this study, the results from monitoring of gully-growth with high-resolution aerial photography are combined with the characterisation of the gully catchments with mapping of soil surface types and morphology and rainfall simulations. The results show an extremely high variability of gully-growth dynamics, being it independent from the size of the contributing catchment and rainfall characteristics. The distribution of soil surface types and their infiltration and erosion characteristics are identified as determinant for gully-growth. Additionally, their position related to the active gully-headcut is identified as determinant for the observed gully development

To assess, by using quantitative MRI metrics, structural and metabolic brain abnormalities in subjects with preclinical cerebral autosomal dominant arteriopathy with subcortical infarcts and leucoencephalopathy (CADASIL).Brain MRI abnormalities have been occasionally reported in preclinical CADASIL subjects. However, very little is known as to when the brain tissue damage starts to accumulate, what brain regions are primarily involved and whether the brain damage is significant in subjects who have no overt clinical manifestations of the disease.Twelve subjects (mean age 40 years; range 26-55 years; males/females 6/6) with genetically proven CADASIL and no clinical signs of the disease underwent conventional MRI and proton MR spectroscopic imaging ((1)H-MRSI) to measure white matter (WM) lesion volume (LV), global and regional cerebral volumes, and WM levels of N-acetylaspartate (NAA) normalised to creatine (Cr). MR values were compared with those of 13 age- and sex-matched healthy controls.All preclinical CADASIL showed WM lesions (range 0.2 to 26 cm(3)). They were mostly distributed in the frontal and parietal regions, with the highest probability in the corona radiata. On (1)H-MRSI examination, NAA/Cr values were lower in preclinical CADASIL than in HC, particularly in the corona radiata (p0.01). Normalised brain and cortical volumes were also lower in preclinical CADASIL than in HC (p0.01), particularly in the frontal cortex.The pathological process occurring in CADASIL leads to damage of WM and neocortex much before the evidence of clinical symptoms. At this preclinical stage, this seems to take place prevalently in the frontal brain region.

Aim To present a method that assesses the influence of environmental variables, including climate, substrate, topography, and anthropogenic disturbances, on the distribution of Andean forest at the tree line, and to compare this forest distribution between areas. Location Sangay National Park, on the eastern slopes of the Andes in central Ecuador. Methods A logistic regression model was built using topographical variables and environmental indices, derived from a digital elevation model, to explain forest cover, derived from a Landsat ETM image, in a zone around the average tree line altitude. Results The model shows that after altitude, which can explain about 80% of forest cover, wetness has the next strongest effect (areas accumulating water, but also cold air, were devoid of forest, resulting in inverted tree lines), followed by eastness (western slopes had forest to higher altitudes). Application of the model in two nearby areas showed that the real tree line was lower than the predicted tree line in both areas, probably owing mainly to macroclimatic differences in one area, and partly also to human land use in the other. The locations with the largest deviations could be the focus of further research concerning human impacts on tree line vegetation. Main conclusions The tree line is located at lower altitudes on east-facing slopes, which may be because high levels of radiation are received by east-facing slopes in the clear mornings, resulting in the photoinhibition of tree seedlings in the páramo. In spite of the limitations of the quality and resolution of the remote sensing data, the presented method provides indications for important ecological factors at the tree line. The method also allows the detection of differences in tree line position between areas, which may reflect climatic differences or the location of anthropogenic disturbances.

Water temperature is an important determinant in many aquatic biological processes, including the growth and development of malaria mosquito (Anopheles arabiensis and A. gambiae) immatures. Water turbidity affects water temperature, as suspended particles in a water column absorb and scatter sunlight and hence determine the extinction of solar radiation. To get a better understanding of the relationship between water turbidity and water temperature, a series of semi-natural larval habitats (diameter 0.32 m, water depth 0.16 m) with increasing water turbidity was created. Here we show that at midday (1300 hours) the upper water layer (thickness of 10 mm) of the water pool with the highest turbidity was on average 2.8 degrees C warmer than the same layer of the clearest water pool. Suspended soil particles increase the water temperature and furthermore change the temperature dynamics of small water collections during daytime, exposing malaria mosquito larvae, which live in the top water layer, longer to higher temperatures.

Oviposition behaviour and egg distribution of Ostrinia nubilalis is reviewed based on published information and new research. The position of egg masses of O. nubilalis on maize plants and leaves were sampled in the field. Most egg masses were found on the lower leaf side, on the middle part of the leaf or close to the stem, and close to the mid-rib. Direct observations of oviposition behaviour were made in laboratory and field cages. O. nubilalis moved very little on the plants and only 10 % of the females that landed on the plants oviposited. The number of actual ovipositions was quite low compared to the number of landings, with females walking only a few centimetres if at all. Shed scales of adult moths were not abundant near egg masses with only 37% of egg masses associated with scales and 45% with only a few scales. Many scales were found on other places of the plants. At the leaf and plant level, scales might serve as a useful host-cue to Trichogramma brassicae, an egg parasitoid of O. nubilalis. However, scales are not an indicator for the presence of egg masses in their immediate vicinity.

The Kattegat in the inner Danish waters has been trawled for at least 80 yr, but so far only few attempts have been made to quantify the trawl effort, its spatial distribution and its potential ecological impact on the benthic fauna. GIS-analyses of VMS-data from trawling in the Kattegat by both Danish (2005-2009) and Swedish (2007-2009) vessels show that 95% of all trawling occurs below 22 m depth. Most activity takes place on homogeneous benthic habitats with muddy sediment at depths below the halocline and with almost the same salinity across the entire area. Furthermore, the estimate of trawled area demonstrated that the habitats are nearly 100% impacted, and frequencies of trawling beneath 100 m depth can reach 20 events per year. Multivariate analysis of community composition could not discriminate between lightly trawled and heavily trawled areas. However, a strong habitat selectivity of the trawl activity and inter-correlation between trawl activity and depth-related community structures complicated interpretation of the results. Species with biological traits previously categorized as sensitive to physical disturbance showed higher abundance in areas with low trawl activity compared to areas with higher activity. Thus, the Kattegat has been impacted to an extent where areas with reference conditions for certain habitats below 22 m no longer exist. Consequently, it is unknown how the benthic communities would have appeared without trawl disturbance and, thus, difficult to determine the impact of continued disturbance.

We study the orientation and speed tuning properties of spatiotemporal three-dimensional (3D) Gabor and motion energy filters as models of time-dependent receptive fields of simple and complex cells in the primary visual cortex (V1). We augment the motion energy operator with surround suppression to model the inhibitory effect of stimuli outside the classical receptive field. We show that spatiotemporal integration and surround suppression lead to substantial noise reduction. We propose an effective and straightforward motion detection computation that uses the population code of a set of motion energy filters tuned to different velocities. We also show that surround inhibition leads to suppression of texture and thus improves the visibility of object contours and facilitates figure/ground segregation and the detection and recognition of objects.

In this study, the LAPSUS-LS landslide model, together with a digital terrain analysis of topographic attributes, is used as a spatially explicit tool to simulate recent shallow landslides in Manjiya County on the Ugandan slopes of Mount Elgon. Manjiya County is a densely populated mountainous area where landslides have been reported since the beginning of the twentieth century. To better understand the causal factors of landsliding, 81 recent landslides have been mapped and investigated. Through statistical analysis it was shown that steep concave slopes, high rainfall, soil properties and layering as well as human interference were the main factors responsible for landslides in the study area. LAPSUS-LS is used to construct a landslide hazard map, and to confirm or reject the main factors for landsliding in the area. The model is specifically designed for the analysis of shallow landslide hazard by combining a steady state hydrologic model with a deterministic infinite slope stability model. In addition, soil redistribution algorithms can be applied, whereby erosion and sedimentation by landsliding can be visualized and quantified by applying a threshold critical rainfall scenario. The model is tested in the Manjiya study area for its ability to delineate zones that are prone to shallow landsliding in general and to group the recent landslides into a specific landslide hazard category. The digital terrain analysis confirms most of the causal topographic factors for shallow landsliding in the study area. In general, shallow landslides occur at a relatively large distance from the water divide, on the transition between steep concave and more gentle convex slope positions, which points to concentration of (sub)surface flow as the main hydrological triggering mechanism. In addition, LAPSUS-LS is capable to group the recent shallow landslides in a specific landslide hazard class (critical rainfall values of 0.03– 0.05 m day −1 ). By constructing a landslide hazard map and simulating future landslide scenarios with the model, slopes in Manjiya County can be identified as inherently unstable and volumes of soil redistribution can yield four times higher than currently observed. More than half of this quantity can end up in the stream network, possibly damming rivers and causing major damage to infrastructure or siltation and pollution of streams. The combination of a high population density, land shortage and a high vulnerability to landslides will likely continue to create a major sustainability problem. © 2007 Elsevier B.V. All rights reserved.

Field observations were made in three years continuous maize cultivation in the Netherlands to study the spatial pattern and stability of spatial pattern over time in agricultural weeds. Two-dimensional correlograms were made, using data from single years, to characterise spatial correlation and pattern, while data from two different years were used to calculate correlation over space and time, to characterise the stability of pattern. Weeds that were able to attain high recruitment also exhibited the strongest spatial correlations. These weeds were Echinochloa crus-galli, Chenopodium album, Chenopodium polyspermum and Solanum nigrum. Weeds that were less successful in attaining high densities in the maize rotation, also showed less spatial correlation. Wind dispersing Compositae, e.g. Taraxacum officinale, had spatially uncorrelated patterns. All weeds that showed spatial correlation also showed stability in space, except E. crus-galli. The latter species showed marked population increase and the locations and extent of its patches changed over the years. Statistical interpretation of the data is discussed, as are potential consequences for site-specific management and optimal sampling of weeds.

A temporarily closed area established to protect spawning Atlantic cod (Gadus morhua) in the North Sea allowed us to study the response of the Dutch beam trawl fleet exploiting common sole (Solea solea) and plaice (Pleuronectes platessa). A number of vessels left the North Sea 1 month earlier than the normal seasonal pattern. The vessels that continued fishing in the North Sea were concentrated in the remaining open areas. In the first week after the closure, the catch rate decreased by 14%, coinciding with an increase in crowding of 28%. Area specialisation affected the response of individual vessels because vessels without prior experience in the open areas showed a larger decline in catch rate compared with vessels that previously fished in these open areas and were more likely to stop fishing during the closed period. The decrease in catch rate in response to the increase in competitor density allowed us to estimate the strength of the interference competition.

Low temperature inhibits the growth of maize (Zea mays) seedlings and limits yield under field conditions. To study the mechanism of cold-induced growth retardation, we exposed maize B73 seedlings to low night temperature (25°C /4°C, day/night) from germination until the completion of leaf 4 expansion. This treatment resulted in a 20% reduction in final leaf size compared to control conditions (25°C/18°C, day/night). A kinematic analysis of leaf growth rates in control and cold-treated leaves during daytime showed that cold nights affected both cell cycle time (+65%) and cell production (−22%). In contrast, the size of mature epidermal cells was unaffected. To analyze the effect on cell cycle progression at the molecular level, we identified through a bioinformatics approach a set of 43 cell cycle genes and analyzed their expression in proliferating, expanding, and mature cells of leaves exposed to either control or cold nights. This analysis showed that: (1) the majority of cell cycle genes had a consistent proliferation-specific expression pattern; and (2) the increased cell cycle time in the basal meristem of leaves exposed to cold nights was associated with differential expression of cell cycle inhibitors and with the concomitant down-regulation of positive regulators of cell division.

This study has investigated some properties of fishermen's foraging, using Levy flights theory. The case studies examined were a selection of North Sea Dutch and French vessels, for which catch and effort data were collected on a haul-by-haul basis. Foraging behavior could reasonably be represented by a Levy flight process, characterized by an exponentiation factor mu, for both fleets. The properties of fishers' foraging were further investigated for the Dutch fleet using time series analysis. Optimal foraging was found with mu = 1.5, suggesting a slow recovery dynamics of the stocks being harvested. Efficient foraging led to high value per unit effort, while the knowledge of fishing grounds with high stock density is shown to increase foraging efficiency in the short-term future. Only marginal correlations could be found between mu and the other explanatory variables considered (fish prices and fishing effort). (c) 2006 Elsevier B.V. All rights reserved.

Catch rates of sole Solea solea and plaice Pleuronectes platessa in the Dutch beam trawl fleet operating in the North Sea show spatio-temporal variation. The variation in catch rates reflects differences in abundance of the species. Up to 45% of the variation in catch rates can be explained by the time of day of the catch, the engine power of the vessel and the migration cycles of the species. Also, spatial covariance was found in the residual variation for both species using variograms and covariance functions. The ranges of the spatial structure were found to be between approximately 20 to 45 nautical miles, indicating patchy distribution of the species. No differences in the ranges of the spatial structures were found between different seasons. Cross-covariance analysis shows the patches lasted up to two weeks. The implication of the spatial pattern in flatfish for the dynamics of effort allocation is discussed.

We report progress in using the isotopic composition and concentration of Pb in the dentine and enamel of deciduous teeth to provide a high resolution time frame of exposure to Pb during fetal development and early childhood. Isotope measurements (total Pb and (208)Pb/(206)Pb, (207)Pb/(206)Pb ratios) were acquired by laser ablation inductively coupled mass spectrometry at contiguous 100 micron intervals across thin sections of the teeth; from the outer enamel surface to the pulp cavity. Teeth samples (n=10) were selected from two cohorts of children, aged 5-8 years, living in NE England. By integrating the isotope data with histological analysis of the teeth, using the daily incremental lines in dentine, we were able to assign true estimated ages to each ablation point (first 2-3 years for molars, first 1-2 years for incisors+pre-natal growth). Significant differences were observed in the isotope composition and concentration of Pb between children, reflecting differences in the timing and sources of exposure during early childhood. Those born in 2000, after the withdrawal of leaded petrol in 1999, have the lowest dentine Pb levels (0.2µgPb/g) with (208)Pb/(206)Pb (mean ±2σ: 2.126-2.079) (208)Pb/(206)Pb (mean ±2σ: 0.879-0.856) ratios that correlate very closely with modern day Western European industrial aerosols (PM10, PM2.5) suggesting that diffuse airborne pollution was probably the primary source and exposure pathway. Legacy lead, if present, is insignificant. For those born in 1997, dentine lead levels are typically higher (0.4µgPb/g) with (208)Pb/(206)Pb (mean ±2σ: 2.145-2.117) (208)Pb/(206)Pb (mean ±2σ: 0.898-0.882) ratios that can be modelled as a binary mix between industrial aerosols and leaded petrol emissions. Short duration, high intensity exposure events (1-2 months) were readily identified, together with evidence that dentine provides a good proxy for childhood changes in the isotope composition of blood Pb. Our pilot study confirms that laser ablation Pb isotope analysis of deciduous teeth, when carried out in conjunction with histological analysis, permits a reconstruction of the timing, duration and source of exposure to Pb during early childhood. With further development, this approach has the potential to study larger cohorts and appraise environments where the levels of exposure to Pb are much higher.

An estimate of net carbon (C) pool changes and long-term C sequestration in trees and soils was made at more than 100 intensively monitored forest plots (level II plots) and scaled up to Europe based on data for more than 6000 forested plots in a systematic 16 km x 16 km grid (level I plots). C pool changes in trees at the level II plots were based on repeated forest growth surveys At the level I plots, an estimate of the mean annual C pool changes was derived from stand age and available site quality characteristics. C sequestration, being equal to the long-term C pool changes accounting for CO2 emissions because of harvest and forest fires, was assumed 33% of the overall C pool changes by growth. C sequestration in the soil were based on calculated nitrogen (N) retention (N deposition minus net N uptake minus N leaching) rates in soils, multiplied by the C/N ratio of the forest soils, using measured data only (level II plots) or a combination of measurements and model calculations (level I plots). Net C sequestration by forests in Europe (both trees and soil) was estimated at 0.117 Gton yr(-1), with the C sequestration in stem wood being approximately four times as high (0.094 Gton yr(-1)) as the C sequestration in the soil (0.023 Gton yr(-1)). The European average impact of an additional N input on the net C sequestration was estimated at approximately 25 kg C kg(-1) N for both tree wood and soil. The contribution of an average additional N deposition on European forests of 2.8 kg ha(-1) yr(-1) in the period 1960-2000 was estimated at 0.0118 Gton yr(-1), being equal to 10% of the net C sequestration in both trees and soil in that period (0.117 Gton yr(-1)). The C sequestration in trees increased from Northern to Central Europe, whereas the C sequestration in soil was high in Central Europe and low in Northern and Southern Europe. The result of this study implies that the impact of forest management on tree growth is most important in explaining the C pool changes in European forests.

Many stone-covered surfaces on Earth are subject to aeolian deposition of atmospheric dust. This study investigates how the deposition of dust is affected when rock fragments become gradually more embedded in the ground or, inversely, become more concentrated on the surface. Experiments were executed in an aeolian dust wind tunnel with eight different types of pebbles. The following parameters were measured: dust deposition on the pebbles, dust deposition between and underneath pebbles, total dust deposition (pebbles + inter-pebble space), and the fraction, of total deposition, of dust caught by the pebbles alone. The absolute amount of dust deposition and the dust deposition density (dust deposition per unit surface) were studied for each parameter. The effects exerted by pebble size, pebble flattening, pebble elongation and wind speed were also investigated. Dust patterns on and around pebbles were also studied via flow visualization.The absolute amount of dust settling on pebbles decreases the more that the pebbles become embedded. Dust deposition density on pebbles, on the other hand, increases with embedding. The more pebbles become embedded in the soil, the more efficient the process of dust deposition on pebbles becomes. Dust deposition between and underneath pebbles increases with pebble embedding. Dust deposition density between and underneath pebbles is maximum at 50 per cent embedding, showing that in this area dust deposition is most efficient when pebbles are halfway embedded. Total deposition slightly decreases the more pebbles become embedded, but total dust deposition density increases with embedding. Aerodynamic flow separation and diverging and converging airflow play an important role in the process of dust deposition on stone-covered surfaces. The more pebbles protrude above the soil, the more they act as an obstacle and the more they disturb the air and dust flow creating scouring zones, flow separation bubbles and shelter areas for the dust. All these effects diminish as pebbles become more embedded in the soil. However, perturbations in dust patterns remain visible until pebbles have disappeared entirely

The mosquito sampling efficiency of a new bed net trap (the Mbita trap) was compared with that of the Centers for Disease Control miniature light trap (hung adjacent to an occupied bed net) and the human landing catch in western Kenya. Overall, the Mbita trap caught 48.7 +/- 4.8% (mean SEM) the number of Anopheles gambiae Giles sensu lato caught in the human landing catch and 27.4 +/- 8.2% of the number caught by the light trap. The corresponding figures for Anopheles funestus Giles were 74.6 +/- 1.3% and 39.2 +/- 1.9%, respectively. Despite the clear differences in the numbers of mosquitoes caught by each method, both the Mbita trap and light trap catches were directly proportional to human landing catches regardless of mosquito density. No significant differences in parity or sporozoite incidence were observed between mosquitoes caught by the three methods for either An. gambiae s.l. or An. funestus. Identification of the sibling species of the An. gambiae complex by a polymerase chain reaction indicated that the ratio of An. gambiae Giles sensu stricto to An. arabiensis Patton did not vary according to the sampling method used. It is concluded that the Mbita trap is a promising tool for sampling malaria vector populations since its catch can be readily converted into equivalent human biting catch, it can be applied more intensively, it requires neither expensive equipment nor skilled personnel, and it samples mosquitoes in an exposure-free manner. Such intensive sampling capability will allow cost-effective surveillance of malaria transmission at much finer spatial and temporal resolution than has been previously possible.

Molecular methods based on soil DNA extracts are increasingly being used to study the fungal diversity of ectomycorrhizal (EM) fungal communities in soil. Contrary to EM root tip identification, the use of molecular methods enables identification of extramatrical mycelia in soil. To compare fungal diversity as determined by root tip identification and mycelial identification, six soil samples were analysed. Root tips were extracted from the six samples and after amplification, the basidiomycete diversity on the root tips was analysed by denaturing gradient gel electrophoresis (DGGE). The soil from the six samples was sieved, total soil DNA was extracted and after amplification, the basidiomycete diversity in the soil fractions was analysed by DGGE. Fourteen different bands were excised from the DGGE gel and sequenced; fungal taxon names could be assigned to eight bands. Out of a total of 14 fungal taxa detected in soil, 11 fungal taxa were found on root tips, of which seven were EM fungal taxa. To examine whether the sieving treatment would affect EM species diversity, two different sieve mesh sizes were used and in addition, the organic soil fraction was analysed separately. DGGE analysis showed no differences in banding pattern for the different soil fractions. The organic fraction gave the highest DGGE band intensities. This work demonstrates that there is a high correspondence between basidiomycete diversity detected by molecular analysis of root tips and soil samples, irrespective of the soil fraction being analysed.

Summary • Studies of ectomycorrhizal fungal communities in forest soils are usually restricted to the uppermost organic horizons. Boreal forest podzols are highly stratified and little is known about the vertical distribution of ectomycorrhizal communities in the underlying mineral horizons. • Ectomycorrhizal root tips were sampled from seven horizons in three continuous columns of a 52-cm deep podzol profile. Root tips were sorted into morphological groups and the colonising fungi identified by sequencing of the rDNA ITS region. The vertical distribution of mycorrhizal taxa was examined. • A relationship between ectomycorrhizal species composition and soil horizon was found. Tomentellopsis submollis, three Piloderma species and Dermocybe spp. were found predominantly in the upper horizons while Suillus luteus, Lactarius utilis and three undescribed Piloderma species were associated with the mineral horizons. • Two thirds of the root tips were found in the mineral soil and half of the taxa were restricted to the mineral horizons. The results highlight the need to include the mineral soil in order to gain a more accurate representation of the ectomycorrhizal community.

Mechanistic insights and predictive understanding of the spatial distributions of foragers are typically derived by fitting either field measurements on intake rates and food abundance, or observations from controlled experiments, to functional response models. It has remained unclear, however, whether and why one approach should be favoured above the other, as direct comparative studies are rare. The field measurements required to parameterize either single or multi-species functional response models are relatively easy to obtain, except at sites with low food densities and at places with high food densities, as the former will be avoided and the second will be rare. Also, in foragers facing a digestive bottleneck, intake rates (calculated over total time) will be constant over a wide range of food densities. In addition, interference effects may depress intake rates further. All of this hinders the appropriate estimation of parameters such as the 'instantaneous area of discovery' and the handling time, using a type II functional response model also known as 'Holling's disc equation'. Here we compare field- and controlled experimental measurements of intake rate as a function of food abundance in female bar-tailed godwits Limosa lapponica feeding on lugworms Arenicola marina. We show that a fit of the type II functional response model to field measurements predicts lower intake rates (about 2·5 times), longer handling times (about 4 times) and lower 'instantaneous areas of discovery' (about 30-70 times), compared with measurements from controlled experimental conditions. In agreement with the assumptions of Holling's disc equation, under controlled experimental settings both the instantaneous area of discovery and the handling time remained constant with an increase in food density. The field data, however, would lead us to conclude that although handling time remains constant, the instantaneous area of discovery decreased with increasing prey densities. This will result into highly underestimated sensory capacities when using field data. Our results demonstrate that the elucidation of the fundamental mechanisms behind prey detection and prey processing capacities of a species necessitates measurements of functional response functions under the whole range of prey densities on solitary feeding individuals, which is only possible under controlled conditions. Field measurements yield 'consistency tests' of the distributional patterns in a specific ecological context.

We present a detailed clustering analysis of the young stellar population across the star-forming ring galaxy NGC 6503, based on the deep HST photometry obtained with the Legacy ExtraGalactic UV Survey (LEGUS). We apply a contour-based map analysis technique and identify in the stellar surface density map 244 distinct star-forming structures at various levels of significance. These stellar complexes are found to be organized in a hierarchical fashion with 95% being members of three dominant super-structures located along the star-forming ring. The size distribution of the identified structures and the correlation between their radii and numbers of stellar members show power-law behaviors, as expected from scale-free processes. The self-similar distribution of young stars is further quantified from their autocorrelation function, with a fractal dimension of ~1.7 for length-scales between ~20 pc and 2.5 kpc. The young stellar radial distribution sets the extent of the star-forming ring at radial distances between 1 and 2.5 kpc. About 60% of the young stars belong to the detected stellar structures, while the remaining stars are distributed among the complexes, still inside the ring of the galaxy. The analysis of the time-dependent clustering of young populations shows a significant change from a more clustered to a more distributed behavior in a time-scale of ~60 Myr. The observed hierarchy in stellar clustering is consistent with star formation being regulated by turbulence across the ring. The rotational velocity difference between the edges of the ring suggests shear as the driving mechanism for this process. Our findings reveal the interesting case of an inner ring forming stars in a hierarchical fashion., MNRAS Accepted 2015 June 11; in original form 2015 May 04 (21 pages, 21 figures, 4 tables)

Where knowledge-based firms are located is important because entrepreneurship, firm creation and innovation are typically associated with regional economic development, wealth creation and increased employment. In this paper we examine where academic entrepreneurs locate their firms. We begin by developing a theoretical model that examines the location choice of the academic entrepreneur within the standard utility maximization theory. Academic entrepreneurs are assumed to maximize their utility by allocating their efforts between academic and entrepreneurial pursuits which, in turn, determine their future streams of income and end-period wealth. Optimal allocation turns out to be a function of both personal and external factors that condition the relevant payoffs and such factors can be empirically observed. We then use several candidate explanatory variables to examine those factors that may influence the firm location choice for 187 biopharmaceutical firms started by 275 academic entrepreneurs in the US. From our empirical analysis we find that location-specific factors such as proximity to certain knowledge assets and to the funding venture capital firms, affect the firm location choice of academic entrepreneurs. Nevertheless, entrepreneur-specific characteristics, such as their age, seem to dominate the choice of firm location.\ud \ud

Gully cut-and-fill dynamics are often thought to be driven by climate and/or deforestation related to population pressure. However, in this case-study of nine representative catchments in the Northern Ethiopian Highlands, we find that neither climate changes nor deforestation can explain gully morphology changes over the twentieth century. Firstly, by using a Monte Carlo simulation to estimate historical catchment-wide curve numbers, we show that the landscape was already heavily degraded in the nineteenth and early twentieth century – a period with low population density. The mean catchment-wide curve number (> 80) one century ago was, under the regional climatic conditions, already resulting in considerable simulated historical runoff responses. Secondly, twentieth century land-cover and runoff coefficient changes were confronted with twentieth century changing gully morphologies. As the results show, large-scale land-cover changes and deforestation cannot explain the observed processes. The study therefore invokes interactions between authigenic factors, small-scale plot boundary changes, cropland management and sociopolitical forces to explain the gully cut processes. Finally, semi-structured interviews and sedistratigraphic analysis of three filled gullies confirm the dominant impact of (crop)land management (tillage, check dams in gullies and channel diversions) on gully cut-and-fill processes. Since agricultural land management – including land tenure and land distribution – has been commonly neglected in earlier related research, we argue therefore that it can be a very strong driver of twentieth century gully morphodynamics.

This study investigates the effects of fracture strain and fracture stress on oral breakdown, bolus formation and sweetness intensity of semi-solid food gels containing sucrose heterogeneously distributed in layers. The sweetness intensity of gels was mainly affected by the total surface area of gel fragments formed upon chewing. Gels with low values of fracture strain and fracture stress broke down into a large number of small fragments. These gels were perceived sweeter than gels with high values of fracture strain and fracture stress. Fracture strain had a larger impact on oral breakdown behavior and sweetness intensity than fracture stress. Results indicate that the oral breakdown behavior (i.e. formation of a large number of small fragments, which leads to an increase in the total surface area) is the driving factor for taste perception in semi-solid gels that have a heterogeneous distribution of sucrose. We suggest that the differences in sweetness intensity in gels containing sucrose heterogeneously distributed in layers and differing in fracture properties result from differences in the frequency of stimulation of taste receptors. An increase in the total surface area of fragments containing sucrose facilitates the release of tastants and increases the frequency of stimulation of taste receptors. Consequently, the taste intensity of gels is enhanced.

都市域とその周辺における大気メタン濃度の観測・解析結果について示す。2001年度に実施した2回の航海観測においても, これまでの観測結果と同様に, 伊勢湾海上に大気メタンの高濃度域がみられた。このような分布はその状況からみて, いずれも陸域からの輸送によるものと推定される。前報(II)で, 滋賀県や周辺府県の大気汚染常時観測点における大気メタン年平均値の分布と年々変動にみられた特徴的差異について, 1時間毎の観測値を用いて再検討した。さらに, 主成分分析によって, 濃度分布の季節変化・年々変化の特徴を抽出した。, In the first part we analyzed the spatial distribution of the atmospheric methane over Ise Bay, and it is indicated that the maximum concentration area over Ise Bay connects to the maximum over the surrounding land area.Secondly, we closely examined the analytical result of the long-term observational hourly data of atmospheric methane in Shiga and surrounding prefectures;and described several characteristic features of the year-to-year and seasonal variations of the spatial distribution of the atmospheric methane obtained from the principal component analysis.

A physical-biological coupled model was used to estimate the effect of the physical processes at the Strait of Gibraltar over the biogeochemical features of the Atlantic Inflow (AI) towards the Mediterranean Sea. This work was focused on the seasonal variation of the biogeochemical patterns in the AI and the role of the Strait; including primary production and phytoplankton features. As the physical model is 1D (horizontal) and two-layer, different integration methods for the primary production in the Biogeochemical Fluxes Model (BFM) have been evaluated. An approach based on the integration of a production-irradiance function was the chosen method. Using this Plankton Functional Type model (BFM), a simplified phytoplankton seasonal cycle in the AI was simulated. Main results included a principal bloom in spring dominated by nanoflagellates, whereas minimum biomass (mostly picophytoplankton) was simulated during summer. Physical processes occurring in the Strait could trigger primary production and raised phytoplankton biomass (during spring and autumn), mainly due to two combined effects. First, in the Strait a strong interfacial mixing (causing nutrient supply to the upper layer) is produced, and, second, a shoaling of the surface Atlantic layer occurs eastward. Our results show that these phenomena caused an integrated production of 105 g C m−2 year−1 19 in the eastern side of the Strait, and would also modify the proportion of the different phytoplankton groups. Nanoflagellates were favored during spring/autumn while picophytoplankton is more abundant in summer. Finally, AI could represent a relevant source of nutrients and biomass to Alboran Sea, fertilizing upper layer of this area with 4.95 megatons nitrate year-1 and 0.44 megatons C year-124 . A main advantage of this coupled model is the capability of solving relevant high resolution processes as the tidal forcing without an expensive performance, allowing to assess the effect of these phenomena on the biogeochemical patterns at longer time scales.e biogeochemical seasonal cycle in the Strait of Gibraltar, JRC.H.1-Water Resources

In many species, individuals express phenotypic characteristics that enhance their competitiveness, that is, the ability to acquire resources in competition with others. Moreover, the degree of competitiveness varies considerably across individuals and in time. By means of an evolutionary model, we provide an explanation for this finding. We make the assumption that investment into competitiveness enhances the probability to acquire a high-quality resource, but at the same time reduces the ability of exploiting acquired resources with maximal efficiency. The model reveals that under a broad range of conditions competitiveness either converges to a polymorphic state, where individuals differing in competitive ability stably coexist, or is subject to perpetual transitions between periods of high and low competitiveness. The dynamics becomes even more complex if females can evolve preferences for (or against) competitive males. In extreme cases, such preferences can even drive the population to extinction.

International audience; There are concerns that outbreaks of exotic or novel vector-borne viral diseases will increasingly occur within northern Europe and the UK in the future. African horse sickness (AHS) is a viral disease of equids that is transmitted by Culicoides and is associated with up to 95 per cent mortality. AHS has never occurred in the UK; however, it has been suggested that appropriate Culicoides species and climatic conditions are present in northern Europe to support an outbreak. No data are currently available regarding the Culicoides species present on UK equine properties. This study demonstrates the presence of potential AHS virus vector Culicoides species on both urban and rural equine properties within the south-east UK. PCR analysis revealed that engorged members of these species contained equine DNA, proving a direct vector-host interaction. It is therefore possible that an AHS outbreak could occur in the UK if the virus were to be imported and, given the severe welfare and economic consequences of AHS, this would have devastating consequences to the naive UK equine population.

Using highly polymorphic microsatellite markers, we assessed clonal structure and paternity in a population of the bryophyte species Polytrichum formosum. Identical multilocus genotypes of individual shoots were almost never observed in spatially separated cushions, but were found to be highly clustered within moss cushions. Therefore, asexual reproduction through dispersal of gametophyte fragments is not very important in P. formosum. However, asexual reproduction on a very localized scale through vegetative growth of genets (branching of gametophytes via clonal growth of rhizomes) is very extensive. The patchy spatial distribution of genets and the absence of intermingling among genets suggest that this species follows a 'phalanx' clonal growth strategy. Vegetative proliferation of genets will increase their size, and, consequently, will have considerable fitness consequences for individuals in terms of increased genet longevity and reproductive output. Although paternity analysis of sporophytes confirmed male genet size, i.e. gamete production, to be an important determinant of male reproductive fitness, it also showed that the spatial distance to female genets is the predominant factor that governs male reproductive success. Moreover, we showed that male gamete dispersal distances in P. formosum are much further than generally assumed, and are in the order of metres rather than centimetres. Combining the findings, we conclude that the high genotypic diversity observed for this facultatively clonal species is most likely explained by a preponderance of sexual reproduction over clonal reproduction.

都市域とその周辺における大気メタン濃度の観測・解析結果について示す。伊勢湾航海観測と同時に知多半島でも空気採取・分析した。その結果は海上の大気メタン高濃度域が陸域からのものであることを示唆している。バックグラウンド濃度の調査のために, 伊吹山南麓で空気採取して, 水平分布・高度分布・日変化について解析した。関ヶ原を挟んだ東西方向の濃度差や, さらには滋賀県と周辺府県のメタン濃度変化傾向の検討をしたところ, 1991年以降, 両者に明らかな差がみられた。この時期以降に琵琶湖水温とその鉛直分布が大きく変化したことに対応していた。, In the first part we analyze the spatial distribution of the atmospheric methane over Ise Bay and Chita-Peninsula, and it is indicated that the maximum concenntartion area over Ise Bay connects to the maximum over the Chita-Peninsula.Secondly, in order to examine background concentration of methane, we made observations (air-sampling and gas-chromatographic analysis) at the southern part of Mt.Ibuki several times.From analyses of the long-term observational data of atmospheric methane in Shiga-ken and surrounding prefectures we found that the concentration of the atmospheric methane in Shiga is clearly lower than that of its surrounding prefectures afet the year 1991.

The integration between vegetation data, human disturbance factors, and geo-spatial data (Digital Elevation Model (DEM) and image data) is a particular challenge for vegetation mapping in mountainous areas. The present study aimed to incorporate the relationships between species distribution (or vegetation spatial distribution pattern) and topography and human disturbance factors with remote sensing data, to improve the accuracy of mountain vegetation maps. Two different mountainous areas located in Lancang (Mekong) watershed served as study sites. An Artificial Neural Network (ANN) architecture classification was used as image classification protocol. In addition, canonical correspondence analysis (CCA) ordination was applied to address the relationships between topography and human disturbance factors with the spatial distribution of vegetation patterns. We used ordinary kriging at unobserved locations to predict the CCA scores. The CCA ordination results showed that the vegetation spatial distribution patterns are strongly affected by topography and human disturbance factors. The overall accuracy of vegetation classification was significantly improved by incorporating DEM or four CCA axes as additional channels in both the northern and southern study areas. However, there was no significant difference between using DEM or four CCA axes as extra channels in the northern steep mountainous areas because of a strong redundancy between CCA axes and DEM data. In the southern lower mountainous areas, the accuracy was significantly higher using four CCA axes as extra bands, compared to using DEM as an extra band. In the southern study area, the variance of vegetation data explained by human disturbance factors was larger than the variance explained by topographic attributes.

International audience; : Alveolar echinococcosis, caused by the cestode Echinococcus multilocularis, is the most serious parasitic disease for humans in Europe, with a sylvatic life cycle generally between small rodents and red foxes. General expansion of the range of E. multilocularis has been observed across Europe over the last 15years. In France, a westward spread of the known endemic areas of the parasite was described recently. For genotyping, the microsatellite EmsB was used to trace expansion in five French areas. A total of 22 EmsB profiles were identified, with five similar to those previously described in other parts of Europe. An imbalance of genetic diversity was observed between the five areas which also revealed their interconnection with the presence of common profiles, notably the two main profiles both present in all regions except one in the North. These two findings are similar to those described at the European level, highlighting transmission of the parasite by a mainland-island system. A spatio-temporal scenario of the expansion of E. multilocularis can be proposed with spread from the French historical focus in eastern France to the Lorraine, the Champagne-Ardenne and finally the North, while simultaneously another expansion has occurred from the historical focus into the West. The colonization by the parasite into the West and North areas from the historical focus was probably due to the migration of foxes several decades ago. Recent detection of the parasite in new endemic "départements" may be due to more active research rather than a recent spread of the parasite. Regarding the numerous data obtained by the different EmsB analyses, principally across Europe, centralization of all the profiles described in a public databank appears necessary in order to obtain a precise understanding of transmission of the parasite from one country to another.

The impact of water temperature (T), water level (L), photosynthetically active radiation (PAR), and wind speed (V) on the total phosphorus concentration (TP) in shallow eutrophic lake Peipsi, the fourth largest lake in Europe, was studied. We used a long-term dataset (1985-2010) of TP concentrations and weather factors. A Thin Plate Spline (TPS) model was used to predict TP by year, by day of the year, and by geographical coordinates. Deviations between observed and predicted TP values (residuals, or TP anomalies) were related to the weather variables to clarify how the weather anomalies in a year might correlate with the observed fluctuations in TP dynamics. Notable seasonal variations in TP, typical for many shallow lake systems, were found: TP was two to three times higher during late summer-early autumn than during winter. Patterns of TP variability were well predicted by using geographical coordinates, year and day of the year (R2=0.69; Pth day, and as a positive driver in the subsequent season.

Palaearctic Culicoides midges (Diptera: Ceratopogonidae) represent a vital link in the northward advance of certain arboviral pathogens of livestock such as that caused by bluetongue virus. The effects of relevant ecological factors on weekly Culicoides vector abundances during the bluetongue virus serotype 8 epidemics in the Netherlands in 2007 and 2008 were quantified within a hurdle modelling framework. The relative role of meteorological parameters showed a broadly consistent association across species, with larger catches linked to temperature-related variables and lower wind speed. Moreover, vector abundance was found to be influenced by edaphic factors, likely related to species-specific breeding habitat preferences that differed markedly amongst some species. This is the first study on Culicoides vector species in the Netherlands identified during an entomological surveillance programme, in which an attempt is made to pinpoint the factors that influence midge abundance levels. In addition to providing key inputs into risk-mitigating tools for midge-borne pathogens and disease transmission models, the adoption of methods that explicitly address certain features of abundance datasets (frequent zero-count observations and over-dispersion) helped enhance the robustness of the ecological analysis.

Variations of tastant concentration during the consumption of food products were shown to enhance taste intensity. The aim of this study was to investigate the relation between the frequency at which tastant concentration is varied during the consumption of products and the occurrence of taste enhancement. For this purpose, the sweetness intensity of sequences of 4 successive sweet stimuli represented by cubes of a semi-solid gel or spoons of a model custard dessert was assessed. The intensity and the order of the stimuli within the sequences were varied to obtain 4 types of sucrose concentration profile (decreasing, increasing, middle peak and boundary peak) at 2 magnitudes of concentration differences (small and large). Sequences of 4 stimuli containing a constant sucrose concentration were used as a reference. The sweetness intensity of the sequences of successive stimuli was assessed using line scale and time-intensity ratings. Line scale ratings showed that the type of sequence had an effect on sweetness intensity. A sweetness enhancement relative to the reference was observed in sequences that ended with high-intensity stimuli, whereas sweetness suppression was observed in sequences that ended with low-intensity stimuli. The observed sweetness enhancement and suppression were attributed to serial position effects (i.e. recency effects). Time-intensity ratings indicated that each stimulus in the sequences was evaluated individually by the assessors. Sequential effects seem to have occurred during the continuous evaluation of successive stimuli, since preceding stimuli in the sequences affected the evaluation of posterior stimuli. Furthermore, the overall sweetness intensity of the different sequences was not enhanced in relation to the reference. The lack of taste enhancement in sequences exhibiting variations of sucrose concentration was attributed mainly to the long period at which sucrose concentration was varied during the evaluation of the sequences. It was confirmed that the frequency of variation of tastant concentration affects the occurrence of taste enhancement.

The H I mass function (HIMF) for galaxies in the local universe is constructed from the results of the Arecibo H I Strip Survey, a blind extragalactic survey in the 21 cm line. The survey, consisting of two strips covering in total similar to 65 deg(2) of sky, with a depth of cz = 7400 km s(-1) was optimized to detect column densities of neutral gas N-HI > 10(18) cm(-2) (5 sigma). The survey yielded 66 significant extragalactic signals, of which approximately 50% are cataloged galaxies. No free-floating H I clouds without stars are found. VLA follow-up observations of all signals have been used to obtain better measurements of the positions and fluxes and to allow an alternate determination of the achieved survey sensitivity. The resulting HIMF has a shallow faint-end slope (alpha approximate to 1.2) and is consistent-with earlier estimates computed for the population of optically selected gas-rich galaxies. This implies that there is not a large population of gas-rich low-luminosity or low-surface brightness galaxies that has gone unnoticed by optical surveys. The influence of large-scale structure on the determination of the HIMF from the Arecibo H I Strip Survey was tested by numerical experiments and was not found to affect the resulting HIMF significantly. The cosmological mass density of H I at the present time, determined from the survey, Omega(HI)(z = 0) = (2.0 +/- 0.5) x 10(-4) h(-1), is in good agreement with earlier estimates. We determine lower limits for the average column densities (N-HI) of the galaxies detected in the survey and find that none of the galaxies have (N-HI)

WOS:000324300700004; International audience; Little is known about the factors that regulate C mineralisation at the soil pore scale or how these factors vary throughout the pore network. This study sought to understand how the decomposition of organic carbon varies within the soil pore network and to determine the relative importance of local environmental properties relative to biological properties as controlling factors. This was achieved by sterilising samples of soil and reinoculating them with axenic bacterial suspensions using the matric potential to target different locations in the pore network. Carbon mineralisation curves were described with two-compartment first-order models to distinguish CO2 derived from the labile organic carbon released during sterilisation from CO2 derived from organic C unaffected by sterilisation. The data indicated that the size of the labile pool of organic C, possibly of microbial origin, varied as a function of location in the pore network but that the organic carbon unaffected by sterilisation did not. The mineralisation rate of the labile C varied with the bacterial type inoculated, but the mineralisation rate of the organic C unaffected by sterilisation was insensitive to bacterial type. Taken together, the results suggest that microbial metabolism is a less significant regulator of soil organic carbon decomposition than are microbial habitat properties.

Despite no obvious barrier to gene flow, historical environmental processes and ecological specializations can lead to genetic differentiation in highly mobile animals. Ecotypes emerged in several large mammal species as a result of niche specializations and/or social organization. In the North-West Atlantic, two distinct bottlenose dolphin (Tursiops truncatus) ecotypes (i.e. ‘coastal’ and ‘pelagic’) have been identified. Here, we investigated the genetic population structure of North-East Atlantic (NEA) bottlenose dolphins on a large scale through the analysis of 381 biopsy-sampled or stranded animals using 25 microsatellites and a 682-bp portion of the mitochondrial control region. We shed light on the likely origin of stranded animals using a carcass drift prediction model. We showed, for the first time, that coastal and pelagic bottlenose dolphins were highly differentiated in the NEA. Finer-scale population structure was found within the two groups. We suggest that distinct founding events followed by parallel adaptation may have occurred independently from a large Atlantic pelagic population in the two sides of the basin. Divergence could be maintained by philopatry possibly as a result of foraging specializations and social organization. As coastal environments are under increasing anthropogenic pressures, small and isolated populations might be at risk and require appropriate conservation policies to preserve their habitats. While genetics can be a powerful first step to delineate ecotypes in protected and difficult to access taxa, ecotype distinction should be further documented through diet studies and the examination of cranial skull features associated with feeding.

Peer- reviewed This is a pre-copy-editing, author-produced PDF of an article accepted for publication in ICES Journal of Marine Science following peer review. The definitive publisher-authenticated version is available online at: doi: 10.1093/icesjms/fst017, Demersal trawling impacts extensively on the seabed and the extent and frequency of this impact can be assessed using Vessel Monitoring Systems (VMS) data (positional data of fishing vessels). Existing approaches interpolate fishing tracks from consecutive VMS locations (track interpolation) and/or aggregate VMS point data in a spatial grid (point summation). Track interpolation can be quite inaccurate at the current 2-hour time interval between VMS records, leading to biased estimates. Point summation approaches currently only produce relative estimates of impact and are highly sensitive to the grid size chosen We propose an approach that provides absolute estimates of trawling impact from point data and is not sensitive to an arbitrary choice of grid cell size. The method involves applying a nested grid and estimating the swept area (area covered by fishing gear) for each VMS point. We show that the ratio of the swept area to the surface area of a cell can be related to the proportion of the seabed that was impacted by the gear a given number of times. We validate the accuracy of this swept-area ratio approach using known vessel tracks and apply the method to international VMS data in the Celtic Sea., Funder: Marine Institute

International audience; We have tested to what extent the growth ability of several organs of maize share a common genetic control. Every night, leaf elongation rate reaches a maximum value (LERmax) that has a high heritability, is repeatable between experiments and is correlated with final leaf length. Firstly, we summarized quantitative trait loci (QTLs) of LERmax and of leaf length in three mapping populations. Among the 14 consensus QTLs (cQTLs) of leaf length, seven co-located with cQTLs of LERmax with consistent allelic effects. Nine cQTLs of LERmax (4% of the genome) were highly reliable and confirmed by introgression lines. We then compared these QTLs with those affecting the growths of leaves, shoots, roots or young reproductive organs, detected with the same mapping populations in three field experiments or in literature datasets. Five of the nine most reliable cQTLs of LERmax co-located with QTLs involved in the growth of other organs (but not in flowering time) with consistent allelic effects. Reciprocally, two-thirds of the 20 QTLs of growth of different organs co-located with cQTLs of LERmax. Hence, LERmax, as determined in a phenotyping platform, is an indicator of the growth ability of other organs of the plant in controlled or in-field conditions.

Food oral processing as the bridge between food texture, microstructure and sensory perception has gained enormous interest in the last decade. This review provides an overview of the role of the microstructure of soft- and semi-solid foods in food oral processing and sensory perception. Phase separated mixed protein polysaccharide gels and emulsion-filled gels are described as suitable model foods to investigate food oral processing systematically. Special attention is given to the sensory perception of texture, taste and interactions thereof. Several approaches to reduce the salt and sugar content of semi- and soft-solid foods without compromising taste are reviewed. These reduction approaches are based on an understanding of food oral processing in relation to the microstructure of the foods and its breakdown. (c) 2013 Elsevier Ltd. All rights reserved.

In the Northern Ethiopian Highlands, ca.33% of the land is cropland, which is mainly cultivated by smallholders who based on indigenous knowledge plan their cropping system on the basis of spatio-temporal variability in rainfall. To understand the relationships between rainfall variability and cropping systems, a field campaign was undertaken in the rainy season of 2009 when 118 farmers were interviewed at different locations with different environmental characteristics. Five cropping systems were identified, each having a distinct cropping season length and crop association. Cropping systems with shorter cropping seasons were generally on the valleysides, whereas longer cycles occurred in the valley bottoms. The length of cropping season also increased from north-northeast to south-southwest. Crop associations within cropping systems also varied with altitude. Cropping systems changed in response to variation in annual rainfall. This resulted in shifts of cropping systems at catchment and regional scales, with cropping systems having longer cropping seasons where there was greater annual precipitation. The results were scaled up to the whole region by modelling the spatial distribution of cropping systems at a 8x8km(2) resolution over the period 1996-2009. The results indicate that indigenous knowledge is important when assessing the impact of climatic variability on agricultural production and that large inter-annual variability in the duration of crop cover in Northern Ethiopia might be an important, although generally overlooked, explanatory factor for explaining previous land degradation cycles.

Essential fish habitat suitability (EFHS) models and geographic information system (GIS) were combined to describe nursery habitats for three flatfish species (Solea solea, Pleuronectes platessa, Dicologlossa cuneata) in the Bay of Biscay (Western Europe), using physical parameters known or suspected to influence juvenile flatfish spatial distribution and density (i.e. bathymetry, sediment, estuarine influence and wave exposure). The effects of habitat features on juvenile distribution were first calculated from EFHS models, used to identify the habitats in which juvenile are concentrated. The EFHS model for S. solea confirmed previous findings regarding its preference for shallow soft bottom areas and provided new insights relating to the significant effect of wave exposure on nursery habitat suitability. The two other models extended these conclusions with some discrepancies among species related to their respective niches. Using a GIS, quantitative density maps were produced from EFHS models predictions. The respective areas of the different habitats were determined and their relative contributions (density x area) to the total amount of juveniles were calculated at the scale of stock management, in the Bay of Biscay. Shallow and muddy areas contributed to 70% of total juvenile relative abundance whereas only representing 16% of the coastal area, suggesting that they should be considered as essential habitats for these three flatfish species. For S. solea and P. platessa, wave exposure explained the propensity for sheltered areas, where concentration of juveniles was higher. Distribution maps of P. platessa and D. cuneata juveniles also revealed opposite spatial and temporal trends which were explained by the respective biogeographical distributions of these two species, close to their southern and northern limit respectively, and by their responses to hydroclimatic trends. (C) 2013 Elsevier Ltd. All rights reserved.

Organized forestry in Brazil began in the late 1960s, stimulated by a government policy which subsidized afforestation programs from 1967 to 1989 to develop an internationally-competitive wood-based industry, managed by the private sector. Currently, planted forests in Brazil total about 6.9 million ha, from which 4.9 million ha is planted with eucalypt (around 25% of world plantation), 1.6 million ha with pine, and 0.42 M ha with other species. Roundwood consumption of forest plantations totaled 170.1 million m(3) in 2011, eucalypt plantation accounted for 80.6% of this total. Most eucalypt plantations are managed in short rotations (6-8 years) and are established in regions with water, nutritional and frost stresses of low to high degrees. The mean annual increment is 40 m(3) ha(-1) year(-1) roundwood, ranging from 25 to 60 m(3) ha(-1) year(-1) depending on the level of environmental stress. Improving natural resources use efficiency by breeding and matching genotypes to sites and using appropriate site management practices is a key challenge to sustain or increase productivity. The wide range of eucalypt species and hybrids with different climatic and edaphic suitability associated with the easy propagation by seeds and cloning allow the adaptation of plantations to various tropical and subtropical regions in Brazil. The possibility of using eucalypt wood in a range of purposes has led large and small enterprises to establish eucalypt forests for multiple uses. The desirable characteristics in association with the accumulated knowledge on eucalypt silviculture encourage the use of this genus in most plantations. The most important factors in the selective process for a genotype are wood characteristics, productivity level, susceptibility to pests and diseases, drought tolerance, especially in tropical regions (frost free), and frost tolerance in subtropical regions (mostly without water deficit). In regions with pronounced seasonality and moderate to long drought periods, the planting of hybrid genotypes predominates, propagated by cloning. Under subtropical conditions, the planting of single species predominates, propagated by seed. Clonal plantations with interspecific hybrids have been fundamental for eucalypt adaptation in regions under water and nutritional stresses. Given the rapid advances in eucalypt breeding, regarding adaptation to water stress and resistance to diseases and pests, and the adoption of clonal propagation techniques, genotypes are rapidly becoming obsolete and are replaced by more productive ones after harvesting. Thus, the replanting of crops has become a common procedure after the second half of the 1990s in Brazil. This paper describes the basic requirements for integrating genetic and silvicultural strategies to minimize abiotic and biotic constraints in eucalypt plantations. (c) 2013 Elsevier B.V. All rights reserved.

Hourly data (1994-2009) of surface ozone concentrations at eight monitoring sites have been investigated to assess target level and long-term objective exceedances and their trends. The European Union (EU) ozone target value for human health (60 ppb-maximum daily 8-hour running mean) has been exceeded for a number of years for almost all sites but never exceeded the set limit of 25 exceedances in one year. Second highest annual hourly and 4th highest annual 8-hourly mean ozone concentrations have shown a statistically significant negative trend for in-land sites of Cork-Glashaboy, Monaghan and Lough Navar and no significant trend for the Mace Head site. Peak afternoon ozone concentrations averaged over a three year period from 2007 to 2009 have been found to be lower than corresponding values over a three-year period from 1996 to 1998 for two sites: Cork-Glashaboy and Lough Navar sites. The EU long-term objective value of AOT40 (Accumulated Ozone Exposure over a threshold of 40 ppb) for protection of vegetation (3 ppm-hour, calculated from May to July) has been exceeded, on an individual year basis, for two sites: Mace Head and Valentia. The critical level for the protection of forest (10 ppm-hour from April to September) has not been exceeded for any site except at Valentia in the year 2003. AOT40-Vegetation shows a significant negative trend for a 3-year running average at Cork-Glashaboy (-0.13 +/- 0.02 ppm-hour per year), at Lough Navar (-0.05 +/- 0.02 ppm-hour per year) and at Monaghan (-0.03 +/- 0.03 ppm-hour per year-not statistically significant) sites. No statistically significant trend was observed for the coastal site of Mace head. Overall, with the exception of the Mace Head and Monaghan sites, ozone measurement records at Irish sites show a downward negative trend in peak values that affect human health and vegetation. (c) Author(s) 2012. This work is distributed under the Creative Commons Attribution 3.0 License.