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排序方式: 共有144条查询结果,搜索用时 15 毫秒
41.
Guo Chen Camilla Öhgren Maud Langton Kaare F. Lustrup Magnus Nydén Jan Swenson 《Journal of Cereal Science》2013
Frozen storage of bread has a substantial impact on the dynamics of water and ice in the crumb and crust. In this study, the impact was characterized using wheat bread stored at −18 °C for a long term of ∼4 months. The frozen bread incurred a considerable loss of the crumb water that migrated out and formed ice crystals on the bread surface. Such a moisture decrease underwent more rapidly for the bread stored without intact crust, suggesting the specific role of crust during frozen storage. Moisture also redistributed significantly within the frozen crumb, resulting in an elevated crumb heterogeneity of freezable water. This redistribution of freezable water was accompanied by a progressive recrystallization of the crumb-borne ice crystals, which were measured to grow into bulk sizes using a modified calorimetric procedure for analyzing the crumb samples at their as-frozen states. 相似文献
42.
In a reforestation field experiment undertaken in southern Sweden and planted with pedunculate oak, three site preparation
treatments (herbicide application (H), mounding site preparation (MSP) and combined herbicide and mounding treatment (H + MSP))
were compared to an undisturbed control (C). We analysed root spatial and biomass distribution in 48 harvested seedlings.
Compared to the control, both MSP and H treatments resulted in a significantly higher root system biomass (means C: 16.4 g,
H: 45.7 g, MSP: 41.4 g, MSP + H: 102.2 g). The proportion of lateral root biomass increased from 38% (C) to 62% (MSP + H),
while the two remaining treatments (H, MSP) attained percentages of 48% and 51%, respectively. The treatments did not alter
seedlings’ allometry and root:shoot ratio significantly. However, biomass distribution of different root system parts varied
among treatments, so that lateral root biomass increased relative to leaf biomass from C to MSP + H variant. Site preparation
treatments (MSP, MSP + H) increased the horizontal extension of root biomass, compared to C and H variants. We conclude that
mounding site preparation is an efficient method for the reforestation of pedunculate oak stands. Due to the comparative positive
effects on root system development, MSP presents an alternative to herbicide treatment, particularly at sites where the use
of chemicals is restricted. 相似文献
43.
Peter Annighöfer Aitor Ameztegui Christian Ammer Philippe Balandier Norbert Bartsch Andreas Bolte Lluís Coll Catherine Collet Jörg Ewald Nico Frischbier Tsegay Gebereyesus Josephine Haase Tobias Hamm Bastian Hirschfelder Franka Huth Gerald Kändler Anja Kahl Heike Kawaletz Christian Kuehne André Lacointe Na Lin Magnus Löf Philippe Malagoli André Marquier Sandra Müller Susanne Promberger Damien Provendier Heinz Röhle Jate Sathornkich Peter Schall Michael Scherer-Lorenzen Jens Schröder Carolin Seele Johannes Weidig Christian Wirth Heino Wolf Jörg Wollmerstädt Martina Mund 《European Journal of Forest Research》2016,135(2):313-329
44.
Mateusz Liziniewicz Urban Nilsson Eric Agestam Per Magnus Ekö Björn Elfving 《Scandinavian Journal of Forest Research》2016,31(6):583-591
A model was developed for predicting site index (SI) values and top height growth of lodgepole pine in northern Sweden. Data on 169 experimental plots from 61 experiments were used for model construction. Six dynamic site equations derived using the generalized algebraic difference approach (GADA) were tested. All of the equations estimate height and SI values on the basis of a known height and total age, and are base-age invariant. Unbiased parameter estimates were obtained by non-linear modelling without accounting for autocorrelation of residuals. The special formulation of the Hossfeld model and the GADA-transformed logistic function produced the most reliable SI curves. The Hossfeld model is recommended as it did not produce extreme outlying estimates for young stands. The developed model is polymorphic with variable asymptotes and can predict SI and dominant height growth for lodgepole pine between 20 and 50 years old. 相似文献
45.
Anna Filyushkina Niels Strange Magnus Löf Eugene E. Ezebilo Mattias Boman 《Scandinavian Journal of Forest Research》2016,31(1):99-110
The need to integrate non-market ecosystem services into decision-making is widely acknowledged. Despite the exponentially growing body of literature, trade-offs between services are still poorly understood. We conducted a systematic review of published literature in the Nordic countries (Denmark, Norway, Sweden and Finland) on the integration of non-market forest ecosystem services into decision-making. The aim of the review was two-fold: (1) to provide an overview of coverage of biophysical and socio-economic assessments of non-market ecosystem services in relation to forest management; (2) to determine the extent of the integration of biophysical and socio-economic models of these services into decision support models. Our findings reveal the need for wider coverage of non-market ecosystem services and evidence-based modelling of how forest management regimes affect ecosystem services. Furthermore, temporal and spatial modelling of ecosystem impacts remains a challenge. We observed a few examples of multiple non-market services assessments. Integration of non-market services into decision support was performed with either biophysical or socio-economic models, often using proxies and composite indicators. The review reveals that there is scope for more comprehensive and integrated model development, including multiple ecosystem services and appropriate handling of forest management impacts. 相似文献
46.
47.
Stenberg Johan A. Sundh Ingvar Becher Paul G. Björkman Christer Dubey Mukesh Egan Paul A. Friberg Hanna Gil José F. Jensen Dan F. Jonsson Mattias Karlsson Magnus Khalil Sammar Ninkovic Velemir Rehermann Guillermo Vetukuri Ramesh R. Viketoft Maria 《Journal of pest science》2021,94(3):665-676
Journal of Pest Science - Biological control, or biocontrol, is the exploitation of living agents (incl. viruses) to combat pestilential organisms (incl. pathogens, pests, and weeds) for diverse... 相似文献
48.
Stenberg Johan A. Sundh Ingvar Becher Paul G. Björkman Christer Dubey Mukesh Egan Paul A. Friberg Hanna Gil José F. Jensen Dan F. Jonsson Mattias Karlsson Magnus Khalil Sammar Ninkovic Velemir Rehermann Guillermo Vetukuri Ramesh R. Viketoft Maria 《Journal of pest science》2021,94(3):677-677
Journal of Pest Science - A correction to this paper has been published: https://doi.org/10.1007/s10340-021-01386-z 相似文献
49.
Kristina Wallertz Niklas Björklund Karin Hjelm Magnus Petersson Lars-Göran Sundblad 《New Forests》2018,49(6):705-722
In northern Europe, there are high risks of severe pine weevil (Hylobius abietis) damage to newly planted conifer seedlings. Site preparation is one of the most important measures for reducing these risks and as several studies have shown the damage is highly dependent on the amount of pure mineral soil around the seedlings. We investigated effects of three site preparation techniques: (1) disc trenching with a conventional Bracke T26, (2) MidiFlex unit and (3) soil inversion with a Karl Oskar unit on characteristics of the planting spots, growth and pine weevil damage and survival rates of untreated and insecticide treated planted Norway spruce (Picea abies) seedlings. All three site preparation techniques reduced pine weevil damage in comparison with no site preparation, and the proportion of spots with pure mineral soil they created was inversely related to the rate of mortality caused by pine weevil. The results indicate that the quality of the planting spots depends on the technique used. In areas where pine weevil is the major threat to seedling survival, the amount of mineral soil in the planting spots is the most important factor in order to protect the seedling from damage. Without site preparation most planting spots consisted of undisturbed humus. Generally, the Karl-Oskar created the most spots with pure mineral soil, but on very stony soils the Bracke T26 created more mineral soil spots than other methods. Site preparation is a valuable tool in order to improve survival in regeneration areas and it is of great importance to make the right choice of technique depending on the particular circumstances on the actual site. 相似文献
50.
The effects of protein quality, protein content, ingredients, and baking process of flour blends on hearth loaves were studied. The flour blends varied in protein composition and content. Flours of strong protein quality produced hearth loaves with larger loaf volume, larger bread slice area, and higher form ratio (height/width) than flours of weak protein quality. The effect of protein content on hearth loaf depended on the size distribution of the proteins. Increasing protein content was associated with increased percentage of the largest glutenin polymers, and loaf volume and slice area increased significantly. The form ratio, however, remained unchanged with increasing flour protein content. Strong protein quality flours tolerated addition of whole meal flour better than weak protein quality flours. Increased amount of flour with strong protein quality improved hearth bread characteristics to a larger extent than increased protein content. Diacetyl tartaric acid ester of monoglycerides (DATEM) improved hearth bread characteristics, but the effect was small compared with the effect of protein composition. 相似文献