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Abstract: We investigated the thickness and composition of five small alpine mires in Tyrol (Austria), performing a combination of conventional techniques (telescope rods, drilling) and geophysical methods. GPR surveys were carried out using 100 and 200MHz antennas. Geoelectrical profiles supplemented the GPR at two sites; the 2D-surveys were enhanced by additional 1D-profiling. The aim was to achieve data on mire thickness, to cross-check the methods and to find reasons for different performance at the five sites. The investigations contribute to establishing a future protection concept. The formation history of the mires probably goes back to the early Holocene. The three larger mires are terrestrialisation mires, while two mires are formed by paludification. Probing with a metal rod was subject to considerable errors in both directions caused by obstacles and soft underlying layers. Thus, GPR proved to be a favourable addition to conventional depth assessment. At four of five sites, GPR made it possible to depict the base layer of the mires at a high accuracy, while detecting peat internal interfaces was less successful. 2D-resistivity profiling supplemented with 1D-modelling provided excellent additional information on mire base and deeper subsurface; at one site where minerogenic material is washed in, 2D-resistivity proved to be the better choice compared to GPR. [Copyright &y& Elsevier]

Abstract: 2D resistivity methods can provide useful information about moisture distributions within porous historic stonework, especially when used in conjunction with simulated driving rain. Moisture is known to be a highly important factor in the deterioration of porous stone. We report here on a series of experiments on historic walls within the centre of Oxford, UK, which illustrate varying degrees of deterioration (including the formation of gypsum-rich black crusts and exfoliating hollows). Using medical electrodes we have been able to carry out non-invasive and non-destructive 2D resistivity surveys before and after simulated rainfall to investigate the progress of wetting and drying. We have applied tentative calibrations to convert resistivity values to moisture contents. Our results show that rainfall penetrates in predictable ways, with clearly defined wetting and drying fronts. Stone blocks with highly weathered surfaces exhibit the most rapid and high levels of water uptake, but also dry out more quickly than crusted or sound blocks. Thus, positive feedbacks may be encouraged whereby more water is cycled through damaged blocks, thereby enhancing the potential for further damage. [Copyright &y& Elsevier]

Abstract: Numerous rotational and translational slides of different sizes cause considerable economic damage in the Swabian Alb (SW-Germany) and are a challenge for risk assessment. The Öschingen landslide is a typical example for landslides occurring along the escarpment. Lithology consists of Jurassic sedimentary rocks involving clays overlain by marls and limestones. A combination of traditional methods (drilling, mapping, inclinometers) and geophysical techniques (2D-resistivity (ERT), ground-penetrating radar (GPR)) was applied to gain knowledge about the thickness and internal structure of the landslide. The drillings and penetration tests provided point information on landslide extent, structure and material involved. In general, all inclinometers showed very little movement if at all. The GPR results were affected by strong signal attenuation and by overhead reflections from the nearby woods. Despite these general obstacles for the application of GPR on landslides near-surface sediment structures were detected. In the 2D-resistivity sections, higher-resistive limestone blocks reaching 10–15 m in thickness could be clearly distinguished from the underlying bedrock. The detailed two-dimensional data of the electrical resistivity tomography (ERT) along with the rather high survey speed turned out to be the best choice to gain detailed spatial information on thickness and extent of the slope movement. The measured profiles coincide with the GPR data and correspond to borehole data. Surprisingly, all results from the applied methods clearly detected the absence of large landslide blocks in the north-west of the study area. This finding could not be concluded from local geomorphology of this area. Regarding the current landslide displacement derived from the inclinometer measurements, the large landslide blocks seem to be dormant during the measured period. [Copyright &y& Elsevier]

The capability of GPR (ground-penetrating radar) measurements to decipher the sedimentary history of young alluvial plains is investigated. The sediment basins result from the infill of two lakes, which were dammed by high-magnitude rockfalls 400-600 and 200 years ago in an Alpine trough valley. The thickness and structure of the dammed sediments was derived from a series of longitudinal and cross profiles. In order to take advantage of both high penetration and high resolution measurements, we applied 25, 50, 100 and 200 MHz antennas. The radargrams allow for a detailed analysis of the history of the alluvial fill. The pre-existing valley bottom is clearly visible under one of the basins. The profiles display the former clayey lake bottom and illustrate several stages of lake infill. Small-scale sedimentary structures, such as topset beds or foreset beds, are discernible and provide proxy information on water level, sediment supply and phases of infill activity. At the second basin, discordant structures in the adjacent sediment cones indicate the abrupt rise of the base level resulting from the rockfall event. Radar-derived information and historical records of lake retreat were used to reconstruct the sediment budget of the 200 year lifespan of the younger alluvial plane. Therefore, it can be concluded that the sedimentation rates of the twentieth century (489 ± 87 m3/yr) are several times larger than those of the nineteenth century (103 ± 7 m3/yr). A 130-yr rainstorm record suggests that the overall increase in sediment supply in the twentieth century corresponds to increased rainstorm frequencies during warm periods. [ABSTRACT FROM AUTHOR]

Chinese semi-winter rapeseed is genetically diverse from Canadian and European spring rapeseed. This study was conducted to evaluate the potential of semi-winter rapeseed for spring rapeseed hybrid breeding, to assess the genetic effects involved, and to estimate the correlation of parental genetic distance (GD) with hybrid performance, heterosis, general combining ability (GCA) and specific combining ability (SCA) in crosses between spring and semi-winter rapeseed lines. Four spring male sterile lines from Germany and Canada as testers were crossed with 13 Chinese semi-winter rapeseed lines to develop 52 hybrids, which were evaluated together with their parents and commercial hybrids for seed yield and oil content in three sets of field trials with 8 environments in Canada and Europe. The Chinese parental lines were not adapted to local environmental conditions as demonstrated by poor seed yields per se. However, the hybrids between the Chinese parents and the adapted spring rapeseed lines exhibited high heterosis for seed yield. The average mid-parent heterosis was 15% and ca. 50% of the hybrids were superior to the respective hybrid control across three sets of field trials. Additive gene effects mainly contributed to hybrid performance since the mean squares of GCA were higher as compared to SCA. The correlation between parental GD and hybrid performance and heterosis was found to be low whereas the correlation between GCA(f + m) and hybrid performance was high and significant in each set of field trials, with an average of r = 0.87 for seed yield and r = 0.89 for oil content, indicating that hybrid performance can be predicted by GCA(f + m). These results demonstrate that Chinese semi-winter rapeseed germplasm has a great potential to increase seed yield in spring rapeseed hybrid breeding programs in Canada and Europe. [ABSTRACT FROM AUTHOR]

Abstract: Stratified talus deposits are reported from many different mountain environments. Numerous possible explanations are discussed in the literature; however, the sediment stores are rarely accessible as exposures are sparse. We applied ground-penetrating radar (25, 50 and 100 MHz antennae) to gain insight into the internal sediment structures of 23 alpine scree slopes; ten examples are presented in this paper. The study areas are spread over the Eastern European Alps at altitudes ranging from 1500 to 2900 m. The bedrock type is primarily limestone and dolostone; one area is composed of gneiss and mica–schist. GPR turned out to be highly suitable for investigating sediment structures of dry talus debris. The results showed that almost all of the deposits investigated are characterized by pronounced stratification. Several different types of layering were identified. Discordant layers which are restricted to confined parts of the talus are probably related to sediment redistribution processes like surficial debris flows or dry grain flows. These features frequently occur at the uppermost part of the slope caused by overland flow from the adjacent rock face, but may also develop in the downhill part of a talus. One talus in the Reintal area showed surface-parallel, persistent layers of different grain sizes which cannot be explained by any known models. We suggest a novel model of talus development which is driven by climatic fluctuations. In periods of enhanced freeze–thaw activity like the Little Ice Age, the delivery of coarse debris prevails. In warmer climate with a higher frequency of rainstorms, the depletion of finer-grained intermediate stores in less inclined rockwall positions leads to delivery of clasts smaller than 2 cm. The type of layering found within a talus is determined by rockwall parameters like height, steepness, topography and dissection of the rock face. The “storage depletion” model applies to high rockwalls with a considerable volume of intermediate storage. [Copyright &y& Elsevier]

Abstract: Moisture in walls provides a key control on decay processes, but has proved difficult to measure. As part of a larger study investigating the ability of soft wall capping (soil and vegetation) to help conserve ruined monuments we have investigated moisture contents of walls at two ruined abbeys. Two methods of moisture measurement were used, i.e. a novel adaptation of 2D electrical resistivity surveys and the well-established wooden dowel method. Medical ECG electrodes were utilised to provide a completely non-destructive resistivity measurement. At Hailes Abbey wooden dowel and 2D resistivity measurements were made of soft capped vs. uncapped wall sections. The wooden dowels showed drier conditions in the core of the capped sections, although the resistivity surveys were influenced by a different stone structure in the wall core. At Byland Abbey, resistivity surveys indicated drier stone blocks and wetter mortar in the near-surface zone, and illustrated the success of the soft-capping technique in reducing water contents in the core of the wall in comparison with hard-capping with mortar. The 2D resistivity technique is shown to be a useful and fast non-destructive technique with the capacity to provide good spatial and temporal resolution information on moisture distribution in walls. [Copyright &y& Elsevier]

Abstract: Three geophysical methods, ground penetrating radar, 2D-resistivity and seismic refraction were applied to two landform complexes in a high-alpine valley in Switzerland to investigate their internal structure. Results of the different methods were analysed separately, before conclusions about sediment thickness and geomorphologic implications were drawn. The results from the three methods were compared to focus on the quality of the methods and their field utility, with respect to portability of equipment, required man-power and measurement time. In this study, ground penetrating radar and seismic refraction proved to be the most suitable with respect to the quality and resolution of the subsurface information and the level of field utility. Sediment thicknesses of 15 m on a rectilinear slope and more than 30 m on a talus cone have been measured; a backweathering rate of approximately 700 mm ka−1 was established. Furthermore, the radar delivered detailed internal sediment structure as well as interfaces between talus and rock glacier. The combined geophysical investigation produced a detailed image of the subsurface composition of the two landform complexes that enhance the understanding of the paraglacial landform evolution in this hanging valley. [Copyright &y& Elsevier]

Forest fires in the Alps might become more hazardous in the future due to their linkage to high temperatures and drought periods. To understand the driving forces and the actual distribution patterns of forest fires is crucial to adapt to those future challenges. We used the province Tyrol in Austria as a case study area. We tested two machine learning algorithms (MaxEnt and RandomForests) for their capability in use with historic fire data and environmental datasets. Presence-only data of 399 forest fires between 1993 and 2011 was compared with a range of topography, vegetation, climate and socio-economic datasets, in order to find out the main driving parameters of the spatial forest fire distribution and to delimit areas of particular fire danger. The results of both algorithms were compared for agreement and differences. Both algorithms delivered broadly similar results; climate (number of days above a certain fire weather index) and anthropogenic parameters (distance to buildings, population density) are the most important parameters in the current alpine fire regime. The models slightly disagreed on the role of forest type and of topography. Joined model results show a strong concentration of potential fire danger along the main valleys and in the drier Tyrolean Upland. [ABSTRACT FROM AUTHOR]

Abstract: Faba bean (Vicia faba L.) is a cool season grain legume whose acreage has constantly declined in traditional producer countries as it has been replaced by more productive cereal crops. However, faba bean is still considered to have great potential as rainfed crop. In order to satisfy the renewed interest in faba bean cultivation yield stability should be improved by exploiting different germplasm types and sowing seasons. In order to understand of genotype by environment interactions and to compare cultivar performance over years and locations a spring faba bean network was established with 20 cultivars grown over three crop seasons at 13 contrasting locations covering most of Europe. Analysis was performed by heritability-adjusted genotype plus genotype×environment interaction (HA-GGE) biplot analysis. HA-GGE biplot analyses identified that the effect of genotype by environment interaction was higher than the effect of genotypes, allowing identification of three mega-environments, namely Continental, Oceanic, and Mediterranean, in which cultivar performed differently. This supports the need for specific breeding for each specific geoclimatic area. Espresso was the highest yielding cultivar, being also highly stable over the Oceanic and Continental mega-environments. Cultivars Fuego, Hobbit and SR-1060 had also good yield but with a moderate unstability in both Oceanic and Continental mega-environments. Baraca and Alameda yielded poorly at all environments although were the best yielders at Mediterranean locations. Environments as Sumperk and Premesques were identified as the best core test locations for Continental and Oceanic mega-environments, respectively, being the locations in which best genotypes could be most easily identified. [Copyright &y& Elsevier]

Abstract: Ascochyta blight incited by Ascochyta fabae is a widespread disease severely damaging faba bean (Vicia faba) production. Insufficient resistance is available in faba bean cultivars. In an attempt to identify new sources of resistance a germplasm collection of 484 V. faba accessions was screened for resistance to A. fabae under field conditions; stability of resistance of the 19 most resistant accessions was tested in a multi-location experiment in Czech Republic, Estonia, Germany and Spain over two field seasons. Although complete resistance was not found, six accessions showed interesting levels of incomplete resistance. Genotype×environment (G×E) interaction accounted for 42% of the sum of squares of the multi-environment evaluation, revealing instability of the phenotypic expression across environments. Accessions L-831818, V-26 and V-958 stand out for their consistent resistance, being the most resistant and stable across environments. Accessions V-255, V-1020, V-1085 and V-1117 displayed good resistance, but lower stability, with V-1020, V-1085 and V-1117 being more suitable for Córdoba (Mediterranean mega-environment), and V-255 more suitable for Hohenlieth, Jõgeva and Sumperk (Continental mega-environment). [Copyright &y& Elsevier]

With 3 figures and 5 tables Grain legumes are regarded as highly valuable protein source for human and animal nutrition. Legume protein quality is mainly limited by the amino acids (AAs) tryptophan and sulphur AA. Organic farming in particular requires high seed protein quality for livestock feeding, as chemically produced AAs must not be feeded. Breeding attempts to increase contents of limiting AA are required. In the present survey, the AA content of 107 cultivars of important European grain legume species (Lupinus angustifolius, Lupinus luteus, Pisum sativum and Vicia faba) was analysed. AA contents were related to the requirements of growing pigs and human nutrition. Feed quality could be enhanced by choice of high quality varieties according to ideal protein concepts. For example for sulphur, AA feed quality for pigs could be increased by up to 22% (e.g. for L. angustifolius: ideal protein = 100, sample mean = 59.7, sample maximum = 72.7). Regarding livestock nutrition, ranges of limiting AA never reached the qualities reported for soybean seeds. However, an inclusion of high quality legume lines would reduce the need for other high quality components in feed compositions. [ABSTRACT FROM AUTHOR]

Chinese semi-winter rapeseed is genetically diverse from European winter rapeseed. Our objectives were (1) to evaluate the potential of semi-winter rapeseed for winter rapeseed hybrid breeding, (2) to assess the relative importance of general combining ability (GCA) vs. specific combining ability (SCA) among combinations between Chinese semi-winter and European winter rapeseed, and (3) to compare the strategies to predict heterosis based on parental genetic distance (GD) estimated from AFLP marker data and GCA for hybrid performance. Four winter male sterile lines from Germany as testers were crossed with 14 Chinese semi-winter rapeseed lines to develop 56 hybrids, which were evaluated together with their parents and commercial hybrids for seed yield, oil content and protein content under three environments in Germany. The Chinese parental lines were not adapted to local environmental conditions as demonstrated by lacking winter hardiness and poor seed yields per se. However, the hybrids between the Chinese parents and the adapted winter rapeseed lines exhibited high heterosis for seed yield. About 20% of the hybrids were significantly superior to the respective hybrid control under three environments. Additive gene effects mainly contributed to hybrid performance since the variance components of GCA were higher as compared with SCA. The correlation between parental GD and hybrid performance was found to be low whereas the correlation between GCA and hybrid performance was high and significant, with correlation coefficients of 0.95 for seed yield, 0.87 for oil content, and 0.91 for protein content, indicating that GCA can predict hybrid performance. These results demonstrate that Chinese semi-winter rapeseed germplasm has a great potential to increase seed yield in winter rapeseed hybrid breeding programmes in Europe. [ABSTRACT FROM AUTHOR]

In spite of its short history of being an oil crop in China, the Chinese semi-winter rapeseed ( Brassica napus L., 2 n = 38, AACC) has been improved rapidly by intentional introgression of genomic components from Chinese B. rapa (2 n = 20, AA). As a result, the Chinese semi-winter rapeseed has diversified genetically from the spring and winter rapeseed grown in the other regions such as Europe and North America. The objectives of this study were to investigate the roles of the introgression of the genomic components from the Chinese B. rapa in widening the genetic diversity of rapeseed and to verify the role of this introgression in the evolution of the Chinese rapeseed. Ten lines of the new type of rapeseed, which were produced by introgression of Chinese B. rapa to Chinese normal rapeseed, were compared for genetic diversity using amplified fragment length polymorphism (AFLP) with three groups of 35 lines of the normal rapeseed, including 9 semi-winter rapeseed lines from China, 9 winter rapeseed lines from Europe and 17 spring rapeseed lines from Northern Europe, Canada and Australia. Analysis of 799 polymorphic fragments revealed that within the groups, the new type rapeseed had the highest genetic diversity, followed by the semi-winter normal rapeseed from China. Spring and winter rapeseed had the lowest genetic diversity. Among the groups, the new type rapeseed group had the largest average genetic distance to the other three groups. Principal component analysis and cluster analysis, however, could not separate the new type rapeseed group from Chinese normal rapeseed group. Our data suggested that the introgression of Chinese B. rapa could significantly diversify the genetic basis of the rapeseed and play an important role in the evolution of Chinese rapeseed. The use of new genetic variation for the exploitation of heterosis in Brassica hybrid breeding is discussed [ABSTRACT FROM AUTHOR]