On-farm influence of production patterns on total polyphenol content in peach

Peach production in France is constantly confronted with marketing problems due to a decrease in fruit consumption and increasing competition with neighbouring Mediterranean countries. The production of higher quality products using production methods such as organic farming (OF) appears to be a tangible way of differentiating and enhancing peach production. To test this hypothesis, an on-farm study was conducted in one of the major production areas in South-eastern France. Focussing on the peach cultivar, cv. Spring Lady®, paired comparisons were conducted between plots in OF and conventional farming (CF). Farmers' practices were identified and checked against crop measurements and performances (yield, sugar content, size classes) in 2004 (12 plots) and in 2005 (10 plots). Polyphenol contents were assessed as an additional component of fruit quality, using the Folin-Ciocalteu colorimetric method. Organic peaches have a higher polyphenol content at harvest. Contents were 4.8 times higher in 2004, whereas the same phenomenon was not observed in 2005. Levels of nitrogen, yield and tree vigour management appeared to be the key elements responsible for the synthesis of total polyphenols and sugar content This implies new opportunities for improving the nutritional quality of peaches, based on production methods

Long-term behaviour of a dam affected by alkali–silica reaction studied by a multi-scale model

This paper aims to employ a 2D thermo-mechanical multi-scale ASR model for the analysis of a concrete gravity dam in Western Switzerland. Simulation results are compared to the field measurements and observations. Analysis of the results reveals negligible effect of temperature variation on the ASR advancement. The difference in length between the upstream and the downstream faces is identified as the main source for the upstream drift at the level of the crest. Study of the structural effects reveals ASR-related expansion anisotropy and cracks alignment being more pronounced along the upstream part and the foundation. If the former is explained by the transmission of the self-weight, the latter is attributed to the constraining effect of the underlying rock

Soil nitrogen in an organic apple orchard

Introduction The lack of vigour of an organic apple orchard (Smoothee cultivar) planted in 1994 pointed out the management of tree nitrogen supply in this orchard. Serious damages due to Dysaphis plantaginea, the rosy aphid, were also noted on trees. As tree vigour and therefore aphid population levels are related to nitrogen nutrition, the monitoring of soil nitrogen availability was necessary to analyse the causes of these problems. Besides, the aim was to optimise the orchard organic nitrogen fertilisation. Materials and methods From 1994 to 1998, the fertilisation management mainly consisted in compost supply (10 t.ha-1). From 1999 to 2001, autumn compost supply was reduced to 5 t.ha-1, complemented with organic quickly mineralised fertilisers in spring (2 x 20 kg.ha-1 N). Lysimeters have been installed (density of 32 lysimeters per ha) in the orchard at 80 cm from trees in the areas under irrigation emitters; at 35 cm depth in 1999, at 35 cm and 50 cm depth in 2000 and 2001. These lysimeters allowed to sample the soil solution and to measure its nitrate content each week along the vegetative period. Growth of the trees, yield, fruit quality and pests were monitored. Soil and leaf analyses were performed in order to evaluate their nitrogen status. Results During the first year of the experiment (1999), nitrate content in soil solution was low and slightly varied among the tested places. In 2000 and 2001, the orchard homogeneity and the very low risk for nitrate leaching were assessed, as nitrate content in soil solution was comprised between 5 and 15 ppm, and remained lower at 50 cm than at 35 cm depth. Analyses of soil samples before and after the vegetative period led to the same conclusions: soil nitrate content varied between 20 and 30 kg.ha-1 at the end of winter, 15 and 25 kg.ha-1 in autumn. These results suggested that soil nitrate content was low enough to limit nitrate leaching, but sufficient to ensure an appropriated nitrate availability for the apple trees (Bussi and Gojon, 1997). The soil C/N ratio increased (from 8.6 in 1998 to 9.8 in 2001), as a result of the soil organic matter increase due to compost supplies. In our soil conditions, a close to 10 C/N ratio, as measured in 2001, appears to be an adequate level (Delas and Molot, 1983). Leaf nitrogen content decreased from 23.7 g.kg-1 in 1999 to 20.4 g.kg-1 in 2001, and fruit nitrogen content from 2.45 g.kg-1 in 1999 to 1.69 g.kg-1 in 2001; nevertheless these N content remained quite suitable for apple production (Sharples, 1980). Yield varied from 15 to 23 t.ha-1 according to the year, and first choice fruit represented 51 to 75 % of the total harvest. These yield fluctuations were mostly a consequence of the serious damages caused by the rosy aphid. Damages by rosy aphid were serious in 1998 and 2000. In 1998, damages might have been favoured by high soil nitrate content, as a consequence of the 10 t.ha-1 compost yearly applied. In 2000, results showed that trees were not overfertilised, which excluded a stimulation effect of nitrogen. Weather in spring 2000 was wet and hot, which was likely to favour the increase of aphid populations, despite pest management before blooming. Conclusion Soil solution and soil nitrate content are useful tools to check the adequacy of organic fertilisation. They may allow to quickly detect excess or lack of nitrogen fertilisation, in order to correct it. Leaf and fruit nitrogen contents are diagnostic elements to evaluate the nitrogen fertilisation effectiveness in organic apple orchard. In our conditions, the optimisation of nitrogen fertilisation was simultaneous of an effective control of the rosy aphid in 1999 and 2001. However, rosy aphid damages in 2000 were serious, suggesting that this problem is most probably related to multi-factorial causes. References Bussi, C., Gojon, A. (1997). Nitrate reductase activity in leaves of peach trees. J. Hort. Sci., 72 (3), 347-353. Delas, J. and Molot, C. (1983). Effet de divers amendements organiques sur les rendements du maïs et de la pomme de terre cultivés en sol sableux. Agronomie, 3 (1), 19-26. Sharples, R.O. (1980). The influence of orchard nutrition on the storage quality of apples and pears grown in the United Kingdom. In : Mineral Nutrition of Fruit Trees, 17-28

History of Provençal poetry: by C.C. Fauriel ... Tr. from the French, with occasional notes and references to the authorities cited or alluded to in the volume, specimens of verses in the original, and an introduction on the literature of the history of Provençal poetry. By G.J. Adler ...

xl, 496 p. 23cm."Contains only a little over one half [the original work] ... that is ... the preliminary researches on the subject ... and the history of the lyrical poetry of the Troubadours complete.

TIMODAZ report: Deliverable D13 – Simulation of lab and in situ tests

TIMODA

Biogeochemical processes and geotechnical applications: progress, opportunities and challenges

Consideration of soil as a living ecosystem offers the potential for innovative and sustainable solutions to geotechnical problems. This is a new paradigm for many in geotechnical engineering. Realising the potential of this paradigm requires a multidisciplinary approach that embraces biology and geochemistry to develop techniques for beneficial ground modification. This paper assesses the progress, opportunities, and challenges in this emerging field. Biomediated geochemical processes, which consist of a geochemical reaction regulated by subsurface microbiology, currently being explored include mineral precipitation, gas generation, biofilm formation and biopolymer generation. For each of these processes, subsurface microbial processes are employed to create an environment conducive to the desired geochemical reactions among the minerals, organic matter, pore fluids, and gases that constitute soil. Geotechnical applications currently being explored include cementation of sands to enhance bearing capacity and liquefaction resistance, sequestration of carbon, soil erosion control, groundwater flow control, and remediation of soil and groundwater impacted by metals and radionuclides. Challenges in biomediated ground modification include upscaling processes from the laboratory to the field, in situ monitoring of reactions, reaction products and properties, developing integrated biogeochemical and geotechnical models, management of treatment by-products, establishing the durability and longevity/reversibility of the process, and education of engineers and researchers