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81.
Ingrid Seynave Alain Bailly Philippe Balandier Jean-Daniel Bontemps Priscilla Cailly Thomas Cordonnier Christine Deleuze Jean-François Dhôte Christian Ginisty François Lebourgeois Dominique Merzeau Eric Paillassa Sandrine Perret Claudine Richter Céline Meredieu 《Annals of Forest Science》2018,75(2):48
Key message
The diversity of forest management systems and the contrasted competition level treatments applied make the experimental networks of the GIS Coop, a nationwide testing program in the field of emerging forestry topics within the framework of the ongoing global changes.Context
To understand the dynamics of forest management systems and build adapted growth models for new forestry practices, long-term experiment networks remain more crucial than ever.Aims
Two principles are at the basis of the experimental design of the networks of the Scientific Interest Group Cooperative for data on forest tree and stand growth (GIS Coop): contrasted and extreme silvicultural treatments in diverse pedoclimatic contexts.Methods
Various forest management systems are under study: regular and even-aged stands of Douglas fir, sessile and pedunculate oaks, Maritime and Laricio pines, mixed stands of sessile oak, European silver fir, and Douglas fir combined with other species. Highly contrasted stand density regimes, from open growth to self-thinning, are formalized quantitatively.Results
One hundred and eighty-five sites representing a total of 1206 plots have been set up in the last 20 years, where trees are measured regularly (every 3 to 10 years). The major outputs of these networks for research and management are the calibration/validation of growth and yield models and the drawing up of forest management guides.Conclusion
The GIS Coop adapts its networks so that they can contribute to develop growth models that explicitly integrate pedoclimatic factors and thus also contribute to research on the sustainability of ecosystems under environmental and socio-economic changes.82.
Zhi-Qiang Chen Karl Lundén Bo Karlsson Ingrid Vos Åke Olson Sven-Olof Lundqvist Jan Stenlid Harry X. Wu María Rosario García Gil Malin Elfstrand 《European Journal of Forest Research》2018,137(4):517-525
Infections with Heterobasidion parviporum devalue the Norway spruce timber as the decayed wood does not meet the necessary quality requirements for sawing. To evaluate the incorporation of disease resistance in the Norway spruce breeding strategy, an inoculation experiment with H. parviporum on 2-year-old progenies of 466 open-pollinated families was conducted under greenhouse (nursery) conditions. Lesion length in the phloem (LL), fungal growth in sapwood (FG) and growth (D) were measured on an average of 10 seedlings for each family. The genetic variation and genetic correlations between both LL, FG and growth in the nursery trial and wood quality traits measured previously from 21-year old trees in two progeny trials, including solid-wood quality traits (wood density, and modulus of elasticity) and fiber properties traits (radial fiber width, tangential fiber width, fiber wall thickness, fiber coarseness, microfibril angle and fiber length). For both LL and FG, large coefficients of phenotypic variation (>?26%) and genetic variation (>?46%) were detected. Heritabilities of LL and FG were 0.33 and 0.42, respectively. We found no significant correlations between wood quality traits and growth in the field progeny trials with neither LL nor FG in the nursery trial. Our data suggest that the genetic gains may reach 41 and 52% from mass selection by LL and FG, respectively. Early selection for resistance to H. parviporum based on assessments of fungal spread in the sapwood in nursery material, FG, will not adversely affect growth and wood quality traits in late-age performance. 相似文献
83.
Marie Charru Ingrid Seynave Jean-Christophe Hervé Romain Bertrand Jean-Daniel Bontemps 《Annals of Forest Science》2017,74(2):33
Key message
Recent growth changes (1980–2007) in Western European forests strongly vary across tree species, and range from +42% in mountain contexts to ?17% in Mediterranean contexts. These changes reveal recent climate warming footprint and are structured by species' temperature (?) and precipitation (+) growing conditions.Context
Unprecedented climate warming impacts forests extensively, questioning the respective roles of climatic habitats and tree species in forest growth responses. National forest inventories ensure a repeated and spatially systematic monitoring of forests and form a unique contributing data source.Aims
A primary aim of this paper was to estimate recent growth changes in eight major European tree species, in natural contexts ranging from mountain to Mediterranean. A second aim was to explore their association with species’ climatic habitat and contemporary climate change.Methods
Using >315,000 tree increments measured in >25,000 NFI plots, temporal changes in stand basal area increment (BAI) were modelled. Indicators of climate normals and of recent climatic change were correlated to species BAI changes.Results
BAI changes spanned from ?17 to +42% over 1980–2007 across species. BAI strongly increased for mountain species, showed moderate/no increase for generalist and temperate lowland species and declined for Mediterranean species. BAI changes were greater in colder/wetter contexts than in warmer/drier ones where declines were observed. This suggested a role for climate warming, further found more intense in colder contexts and strongly correlated with species BAI changes.Conclusion
The predominant role of climate warming and species climatic habitat in recent growth changes is highlighted in Western Europe. Concern is raised for Mediterranean species, showing growth decreases in a warmer climate with stable precipitation.84.
Ingrid M. Malebane Jones Wilfred Ng’ambi David Norris Christian Mbajiorgu 《Tropical animal health and production》2010,42(8):1711-1718
Two experiments were carried out to determine the effect of dietary ascorbic acid supplementation levels on productivity,
carcass characteristics, and mortality of indigenous Venda chickens. The first experiment determined the effect of dietary
ascorbic acid supplementation levels on productivity and mortality rate of 175 unsexed Venda chickens between 1 and 6 weeks
old. The second experiment determined the effect of dietary ascorbic acid supplementation levels on productivity, carcass
characteristics, and mortality rate of 140 female Venda chickens between 8 and 13 weeks old. A completely randomized design
was used in both experiments. Supplementation of grower diets with ascorbic acid ranged from 0 to 2,000 mg per kg DM feed
in both experiments. Levels of ascorbic acid supplementation for optimum feed intake, feed conversion ratio, growth rate,
live weight, and breast meat yield were determined using a quadratic equation. The optimal dietary ascorbic acid supplementation
levels for feed conversion ratio, growth rate, and live weight of Venda chickens during the starter phase were 1,050, 1,301,
and 1,500 mg/kg DM feed, while, at the grower phase, the optimal supplementation levels for feed conversion ratio, growth
rate, live weight, and breast meat yield were 1,000, 1,250, 1,482, and 769 mg/kg DM feed, respectively. Results indicate that
different levels of ascorbic acid supplementation optimized feed conversion ratio, growth rate, and live weight of Venda chickens
at each growth phase. However, levels of ascorbic acid supplementation for optimum feed conversion ratio, growth rate, and
live weight were higher than that for breast meat yield. These findings have implications on ration formulation for Venda
chickens. 相似文献
85.
Objective To describe the technique for implantation of a novel keratoprosthesis (KP) prototype and evaluate its application for the treatment of corneal blindness in dogs.
Animals studied Seven dogs, all of them being clinically blind before surgery as a result of severe corneal endothelial disease (5/7) or chronic superficial keratitis (2/7) that were unresponsive to prior therapy.
Procedures A silicone KP was implanted unilaterally, just anterior to Descemet's membrane, after creating a stromal pocket by deep stromal lamellar dissection.
Results Implantation of the KP was accomplished without complication in six of seven operated dogs. In the remaining case, an intra-operative complication (perforation of Descemet's membrane) was associated with extrusion of the KP 8 weeks postoperatively. All operated eyes regained limited vision after surgery. Three to six months after implantation purulent keratitis occurred in all five eyes with endothelial disease, necessitating surgical removal of the KP 6 months postoperatively in 5/7 eyes.
Conclusions This KP prototype shows promise as a treatment for certain blinding corneal diseases. However, changes in the design of this KP, allowing improved stromal integration, will be necessary before its clinical application can be approved. 相似文献
Animals studied Seven dogs, all of them being clinically blind before surgery as a result of severe corneal endothelial disease (5/7) or chronic superficial keratitis (2/7) that were unresponsive to prior therapy.
Procedures A silicone KP was implanted unilaterally, just anterior to Descemet's membrane, after creating a stromal pocket by deep stromal lamellar dissection.
Results Implantation of the KP was accomplished without complication in six of seven operated dogs. In the remaining case, an intra-operative complication (perforation of Descemet's membrane) was associated with extrusion of the KP 8 weeks postoperatively. All operated eyes regained limited vision after surgery. Three to six months after implantation purulent keratitis occurred in all five eyes with endothelial disease, necessitating surgical removal of the KP 6 months postoperatively in 5/7 eyes.
Conclusions This KP prototype shows promise as a treatment for certain blinding corneal diseases. However, changes in the design of this KP, allowing improved stromal integration, will be necessary before its clinical application can be approved. 相似文献
86.
Repeatability of fin length measurements using digital image analysis and studies of fin erosion as indicator of social interactions in Atlantic cod (Gadus morhua) 下载免费PDF全文
Yajing He Hanne Marie Nielsen Ingrid Olesen Jørgen Ødegård Børge Damsgård 《Aquaculture Research》2016,47(10):3180-3188
The aims of this study were to examine fin erosion caused by social interactions between Atlantic cod (Gadus morhua) juveniles, and to evaluate the repeatability of recorded fin length using digital image analysis (DIA). Fin length of 2100 juvenile Atlantic cod was analysed using DIA, during a 6 weeks experiment. The lengths of the three dorsal fins and the caudal fin were measured by three different assessors (M, K, B) three times during the experiment. Repeatability was based on a sub set of data from 42 randomly chosen fish. Assessor M measured the length of the fins of the 42 fish three times (M1, M2, M3). M1 and M2 were done on the same day, while M3 was conducted 2 weeks later. Assessor K measured two times with a 2‐year interval, and assessor B measured the fin length only once. The correlations between replicated measurements within assessor were highest for assessor M measured on the same day indicating an effect of memory. Repeatability of fin length ranged from 0.57 to 0.73 for the four fins. Social interaction with respect to fin erosion was studied using data on the four fins from all 2100 fish. ‘Relative fin length’ (fin length/total body length × 100) was calculated to assess fin erosion. Results indicated that all four fins were eroded due to social interactions, but the caudal fin was most severely eroded. In conclusion, DIA can be used to measured fin length but the method could be improved by using chromatic pictures. 相似文献
87.
Domingo JL Ericson-Jogsten I Perelló G Nadal M Van Bavel B Kärrman A 《Journal of agricultural and food chemistry》2012,60(17):4408-4415
In this study, the concentrations of 15 perfluorinated compounds (PFCs) were analyzed in 30 water samples collected in Catalonia (Spain) at three stages of the drinking water treatment process in several water purification plants. In addition, the concentrations of 13 PFCs were determined in samples of fish and shellfish collected from coastal areas of Catalonia. The intake of PFCs through both pathways, drinking water intake and fish and shellfish consumption, was also estimated. In water samples, the highest mean concentrations corresponded to perfluorooctane sulfonate (PFOS) and perfluorooctanoate (PFOA) (1.81 and 2.40 ng/L, respectively), whereas perfluorodecanosulfonate (PFDS) and perfluorotetradecanoic acid (PFTDA) were under their respective limits of detection in all analyzed samples. The results show that although the current treatment processes caused slight reductions in PFC concentrations, these processes did not mean significant changes in the amounts of PFCs already contained in the raw water. Among the analyzed PFCs in fish and shellfish, only seven compounds could be detected in at least one composite sample. PFOS showed the highest mean concentration (2.70 ng/g fw), being detected in all species with the exception of mussels. With regard to PFOA (mean, 0.074 ng/g fw), the highest concentrations were detected in prawn and hake (0.098 and 0.091 ng/g fw, respectively). The current exposure to PFCs through consumption of fish and shellfish indicates that it should not be of concern for the consumers. The amounts ingested are well below the recommended tolerable daily intakes, at least for those PFCs for which information is available. 相似文献
88.
Sahar S Dalahmeh Mikael Pell Bj?rn Vinner?s Lars D Hylander Ingrid ?born H?kan J?nsson 《Water, air, and soil pollution》2012,223(7):3657-3671
Greywater is a potential resource of water that can be improved to meet the quality needed for irrigation. This study evaluated the performance of bark, activated charcoal, polyurethane foam and sand filters in removing biochemical oxygen demand (BOD5), surfactants, phosphorus, nitrogen and microbial indicators from greywater during start-up and steady state. In column experiments, 0.6?m high filters (diameter 20?cm) were fed for 113?days with artificial greywater at a hydraulic loading rate of 0.032?m3?m?2?day?1 and an organic loading rate of 0.014?kg BOD5 m?2?day?1. Bark and activated charcoal efficiently reduced the concentrations of organics (BOD5), surfactants (methylene blue active substances??MBAS), total phosphorus (Tot-P) and total thermotolerant coliform numbers, while sand and foam were less efficient. Bark, activated charcoal, foam and sand reduced influent BOD5 by 98, 97, 37 and 75?%; MBAS by >99, >99, 73 and 96?%; Tot-P by 97, 91, 36 and 78?%; and total nitrogen by 19, 98, 13 and 5?%, respectively. BOD5 and MBAS were efficiently reduced directly from start-up by bark and activated charcoal, while foam needed 30?days to achieve about 50?% reduction in BOD5. Bark was the most efficient filter in reducing thermotolerant faecal coliforms (2.4 log10), while foam achieved the lowest reduction (0.5 log10). Overall, bark and activated charcoal filters appeared to be the most suitable filters for improving greywater quality to reach irrigation quality in terms of organic matter reduction. Performance of these filters under higher and fluctuating loadings and the long-term sustainability of the filter materials need further investigation. 相似文献
89.
90.
De Decker S Gielen IM Duchateau L Saunders JH van Bree HJ Polis I Van Ham LM 《American journal of veterinary research》2011,72(11):1496-1504