Finite element analyses in wood research: a bibliography

This paper gives a bibliographical review of the finite element methods (FEMs) applied in the analysis of wood. The added bibliography at the end of this article contains 300 references to papers and conference proceedings on the subject that were published between 1995 and 2004. The following topics are included: Wood as a construction material—material and mechanical properties; wood joining and fastening; fracture mechanics problems; drying process, thermal properties; other topics. Wood products and structures—lumber; glulam, panels, wood composites; trusses and frames; floors, roofs; bridges; other products/structures.     

Impact of defoliation caused by the sawfly Cephalcia lariciphila (Hymenoptera: Pamphilidae) on radial growth of larch (Larix decidua Mill.)

The period between 2000 and 2002 repeated outbreaks of the web spinning sawfly Cephalcia lariciphila (Wachtl 1898) around the village of Větrny Jeníkov, Czech Republic. The impact of defoliation, caused by C. lariciphila feeding, on tree-ring formation of European larch (Larix decidua Mill.) was studied using dendrochronological methods. Heavy defoliation resulted in much less growth in the years of insect attack, the average incremental loss being 67% for the 2000–2002 period. Also, defoliation resulted in the formation of latewood with fewer cells and reduced cell-wall thickness.     

The first report on natural Enterocytozoon bieneusi and Encephalitozoon spp. infections in wild East-European House Mice (Mus musculus musculus) and West-European House Mice (M. m. domesticus) in a hybrid zone across the Czech Republic-Germany border

To determine the occurrence of potentially human pathogenic microsporidia (Enterocytozoon bieneusi and Encephalitozoon spp.) in wild mice, we examined 289 East-European House Mice (Mus musculus musculus) and West-European House Mice (M. m. domesticus) trapped at 74 localities in an area across the Czech-German border. Microsporidia were detected at 33 localities, in 34% of M. m. musculus and 33% of M. m. domesticus examined specimens. Single-species infection was detected in 23 mice for E. hellem, 42 mice for E. cuniculi and 25 mice for E. bieneusi. No Encephalitozoon intestinalis positive animals were identified. Moreover, co-infections were detected in 6 animals; E. bieneusi co-existed with E. cuniculi or E. hellem in 3 mice. The natural infection of E. hellem has never been recorded in mice before. No differences were found by a statistical analysis of microsporidia occurrence between the House Mouse subspecies. Although the gender-dependent infestation of microsporidia was statistically supported in M. m. musculus, no significant differences were observed when the occurrence of microsporidia was estimated for all males and females irrespective of the House Mouse subspecies. The results of this report document the low host specificity of detected microsporidia species and imply the importance of synanthropic rodents as a potential source of human microsporidial infection.     

Effect of combined nitrogen and sulphur fertilization on yield and qualitative parameters of Camelina sativa [L.] Crtz. (false flax)

Abstract

Camelina (Camelina sativa (L.) Crtz., false flax) is described as a species requiring fewer inputs than other oilseed crops thus making it an interesting alternative in sustainable cropping systems. As information on the combined effects of nitrogen and sulphur on camelina yield and quality parameters is meagre, a pot fertilization experiment was carried out with nitrogen applied as NH₄NO₃ at three increasing rates equivalent to a range from 63 up to 127 kg ha^?1. These treatments were combined with sulphur additions applied as (NH₄)₂SO₄ to achieve a soil sulphate content of 25 or 45 mg kg^?1, respectively (equivalent to 75 and 135 kg S ha^?1). The medium and high nitrogen rates combined with the low sulphur fertilization level increased the number of branches per plant compared with the lowest nitrogen fertilization at the same sulphur rate. Camelina seed yield increased with increasing nitrogen doses at the same low sulphur level, whereas straw yield increased only at the highest rate of nitrogen. Thousand-seed mass increased at the highest nitrogen dose and with the low sulphur application rate. In addition, the increase in nitrogen fertilization reduced seed oil content from 39.8% to 37.1%. A highly negative correlation was observed between oil and protein content of seeds. Nitrogen fertilization increased total oil yield and total protein yield. Differences in crop parameters between the sulphur treatments were not significant statistically, although the higher sulphur treatment tended to increase seed yield as well as oil and protein content compared with the low sulphur treatment. Thus, the combined application of N and S as mineral fertilizers is only recommended when growing camelina on sulphur-deficient soils if the aim is to achieve both high oil and protein production.     

Impacts of otter (Lutra lutra L.) predation on fishponds: A study of fish remains at ponds in the Czech Republic

The increasing numbers of otters (Lutralutra L.), which are protected by the CzechAct of Nature and Landscape Protection, arecausing serious problems for fishpondmanagement. The diet of otters on pond farmsconsists predominantly (80%) of common carp,Cyprinus carpio, and to a lesser extentother pond fish species (perch, Percafluviatilis, zander, Stizostedionlucioperca and grass carp, Ctenopharyngodon idella). The size of carpcaptured by otters ranged between 376–683 mmTL (500 ± 88 mm) and 1,049–11,768 g(3,478 ± 2,867 g). Reconstructed originalweight and length of captured grass carp andperch were 599 and 182 mm TL, and 2,665 and163 g, respectively. In most of prey fishcorpses left by otters, only viscera andassociated parts were consumed. The weight ofindividual common carp corpses was estimated as73.0 ± 24.6 (26.3–95.9)% of theoriginal reconstructed weight, which means thatonly 27.0 ± 17.2 (4.1–73.7)% of fishbody mass was consumed by otters. In perch,62.8% of fish body mass was left unconsumed.Heavy losses have been reported also on fishstocks in ice-covered ponds during the winterperiod, when shoals of resting fish have beendisturbed and stressed due to otter hunting.     

Comparison of lure-baited insecticide-treated tripod trap logs and lure-baited traps for control of Ips duplicatus (Coleoptera: Curculionidae)

Two methods were compared for capturing the bark beetle Ips duplicatus Sahlberg (Coleoptera: Curculionidae, Scolytinae): lure-baited, insecticide-treated tripod trap logs (TRIPODs) versus Theysohn pheromone traps (TPTs). In 2008 and 2011 and at each of three clearcuts, five TPTs and five TRIPODs baited with ID Ecolure pheromone evaporators were installed with 10 m spacing. The pheromone evaporators were renewed every 8 weeks. The TRIPODs were treated with the insecticide Vaztak 10 EC in mid-April and then every 5 weeks thereafter. Trap logs and traps were inspected weekly during the entire period of I. duplicatus flight activity (April–September). Two to three times more beetles were trapped by the TPTs than by the TRIPODs. The TPTs captured more females than males, while TRIPODs captured equivalent numbers of males and females or more males than females on some dates. The TPTs and TRIPODs trapped approximately the same numbers of males, but the TPTs captured more females than the TRIPODs. Both traps captured more adults in spring than in summer. The higher numbers of entomophagous arthropods, including the predacious beetles Thanasimus formicarius L. and T. femoralis, were captured in the TRIPODs than in the TPTs.     

Dendroctonus micans populations on Picea pungens in the center of a non-outbreak region contain few pathogens,parasites or predators: A new threat for urban forests?

In reviewing the occurrence of the bark beetle Dendroctonus micans in the Czech Republic over the past 100 years, we found that D. micans has been detected at 80 localities with elevations ranging from 158 to 1350 m a.s.l. During 2011–2012, we recorded three local outbreaks on Picea pungens, two of which involved isolated trees in urban areas between houses (always on sites <1 ha). From these locally abundant populations, 125 adults, 5 pupae, and 73 larvae of D. micans were obtained and dissected. Among these dissected specimens, nematodes in the hemolymph were detected in only 5 adults and 11 larvae. No other parasites or pathogens were found in the D. micans specimens. Low numbers of the beetle Rhizophagus grandis, which is a specific predator of D. micans, were detected, and none contained parasites or pathogens. Locally D. micans could constitute a new limited threat to urban trees, including P. pungens, in the Czech Republic and Central Europe. Special attention should be given to solitary P. pungens trees; if D. micans is detected on these trees, defensive measures must be taken to protect uninfested trees in the vicinity.     

Further spread of the gypsy moth fungal pathogen,Entomophaga maimaiga,to the west and north in Central Europe

Journal of Plant Diseases and Protection - The gypsy moth, Lymantria dispar, is one of the most important pests of deciduous trees in Europe, occurring in all environmental zones of Europe except...