Wood Surface (wood + surface)

Distribution by Scientific Domains


Selected Abstracts


Spiders (Araneae) associated with downed woody material in a deciduous forest in central Alberta, Canada

AGRICULTURAL AND FOREST ENTOMOLOGY, Issue 4 2001
Christopher M. Buddle
Abstract 1,Spiders (Araneae) were collected on and near downed woody material (DWM) in a Populus -dominated forest to determine if spiders utilize wood surfaces, and to ascertain the importance of DWM habitat and wood elevation for spider assemblages. 2,Over 10 000 spiders representing 100 species were collected. Although more spiders were collected on the forest floor, spider diversity was higher in traps located on wood surfaces than on the forest floor, and 11 species were collected more frequently on wood surfaces. 3,Spiders utilized DWM at different stages in their development. Female Pardosa mackenziana (Keyserling) (Lycosidae) carrying egg sacs were caught most often on the surface of DWM, possibly to sun their egg sacs. Additionally, the proportion of immature spiders was higher on the wood surface than on the forest floor. 4,Spiders collected on logs with and without bark were compared to assemblages collected on telephone poles to assess what features of DWM habitat may be important. Web-building species were seldom collected on telephone poles, suggesting that they depend on the greater habitat complexity provided by DWM. In contrast, hunting spiders did not distinguish between telephone poles and logs. 5,Fewer spiders and a less diverse fauna utilized elevated compared to ground-level wood. Additionally, Detrended Correspondence Analysis revealed that the spider community from elevated wood was distinguishable from the spider community from ground-level wood, and from the forest floor spider community. [source]


157 nm fluorine laser ablation of wooden surfaces as an improved preparation technique for microscopy

LASER PHYSICS LETTERS, Issue 1 2005
M. Kopp
Abstract By means of 157 nm VUV short-wavelength laserirradiation the wood layer of damaged cells near the surface as well as deeper wood regions can be removed. As this is a nonthermal laser ablation-process, oxidation of the wood surface exposed to 157 nm under N2 -atmosphere is avoided even with high power densities. By applying a mechanical pre-treatment process the wood structure is compressed and can then be removed with almost no damage. Four types of wood - spruce, pine, beech and oak - were ablated in all three main cutting directions prescribed for an anisotropic material such as wood. Several microscopic techniques were used. To measure the ablation depth LSM was applied. The surface roughness as well as the quality of the laser ablation was determined by using LV-SEM. CAM was used to measure the contact angle and thereby calculate the surface energy. Ablation can be carried out regardless of the cutting direction used to obtain clean and open surfaces free of artefacts. ( 2005 by ASTRO, Ltd. Published exclusively by WILEY-VCH Verlag GmbH & Co. KGaA) [source]


Can a large metropolis sustain complex herpetofauna communities?

ANIMAL CONSERVATION, Issue 5 2009
An analysis of the suitability of green space fragments in Rome
Abstract Urban areas are primary causes of species' range fragmentation and reduction. However, relatively few studies have attempted to describe the habitat variables influencing the diversity and conservation of amphibians and reptiles, particularly in Mediterranean Europe and in large metropolitan areas. We explored this broad conservation ecology problem by studying the richness and diversity patterns in relation to a suite of six independent habitat variables in Rome, one of the most ancient cities of the world. We considered all the green remnant areas (n=62) of Rome, ranging 1 to >1000 ha in size, which are interspersed within a sea of urbanized matrix. A total of 10 amphibian and 15 reptile species were studied. Their presence/absence patterns were assessed and the effects of the various habitat variables on each species were predicted by a logistic regression model. A total of 1261 presence records (404 amphibians and 857 reptiles) were analysed. Fragment size and wood size within each fragment did correlate significantly with the species richness of both amphibians and reptiles, and there was a clear threshold effect after 50 ha of wooded surface. The presence of water bodies positively affected the species distribution. One amphibian and three reptiles inhabited exclusively fragments >50 ha. The distance from the centre did not affect fragment species richness. The presence of most species of both amphibians and reptiles was positively influenced by the irregular versus circular shape of the wooded area. The legal protection of a given area did not influence the observed patterns but the total number of sheltered species. Overall, our study suggests that, in order to maintain the current diversity and population viability, it is necessary, in addition to water bodies' maintenance, to (1) preserve the wooded landscapes over 50 ha; (2) promote irregularly shaped increases in the wood surface; (3) maintain ecotonal boundaries. [source]


The responses of floodplain primary production to flood frequency and timing

JOURNAL OF APPLIED ECOLOGY, Issue 1 2001
A.I. Robertson
Summary 1,River regulation and abstraction have dramatically altered the natural flow regime of many rivers world-wide, but experimental investigations of the biological effects are infrequent. In the mid-region of the Murray River, Australia, river regulation has reduced the frequency and duration of spring floods and increased the frequency of summer floods. We used controlled floods (treatments: no floods, spring floods, summer floods and spring + summer floods) to determine how the growth of river red gum Eucalyptus camaldulensis trees, aquatic macrophytes and biofilms varied with the seasonal timing and frequency of flooding. 2,After 6 years of controlled flooding, above-ground net production of wood by river red gum trees was equal and greatest in plots receiving spring + summer floods and summer floods (mean 496 g m,2 year,1). Production was significantly lower in plots receiving spring floods or no controlled floods, which had similar rates of production (mean 330 g m,2 year,1). 3,During 2 years of measurement in wetlands created by flooding, production and species richness of aquatic macrophyte were both greater in spring than in summer floods. The history of flood frequency at any experimental site did not affect macrophyte production or species richness. The aquatic macrophyte community in shallow regions of wetlands differed significantly with the seasonal timing of floods, but not flood frequency. 4,The accumulation of chlorophyll a and total mass of biofilm on wood surfaces in wetlands created by flooding were greater in spring (mean chlorophyll a, 088 g cm,2; mean mass, 0066 mg cm,2) than in summer floods (mean chlorophyll a, 009 g cm,2; mean mass, 0034 mg cm,2). The history of flood frequency at any experimental site did not affect accumulation of either the autotrophic or heterotrophic components of biofilms. 5,Spring flooding, while not as beneficial for tree growth, is critical for the growth of wetland macrophytes, the maintenance of macrophyte species richness, and favours better development of autotrophic biofilms. Maintenance of both the timber harvest and wetland conservation values of these floodplains will require the return of more natural flood flows in the spring period. Restoration of floodplain rivers requires a thorough understanding of the relationships between ecological functions and the natural flow regime. [source]


Spiders (Araneae) associated with downed woody material in a deciduous forest in central Alberta, Canada

AGRICULTURAL AND FOREST ENTOMOLOGY, Issue 4 2001
Christopher M. Buddle
Abstract 1,Spiders (Araneae) were collected on and near downed woody material (DWM) in a Populus -dominated forest to determine if spiders utilize wood surfaces, and to ascertain the importance of DWM habitat and wood elevation for spider assemblages. 2,Over 10 000 spiders representing 100 species were collected. Although more spiders were collected on the forest floor, spider diversity was higher in traps located on wood surfaces than on the forest floor, and 11 species were collected more frequently on wood surfaces. 3,Spiders utilized DWM at different stages in their development. Female Pardosa mackenziana (Keyserling) (Lycosidae) carrying egg sacs were caught most often on the surface of DWM, possibly to sun their egg sacs. Additionally, the proportion of immature spiders was higher on the wood surface than on the forest floor. 4,Spiders collected on logs with and without bark were compared to assemblages collected on telephone poles to assess what features of DWM habitat may be important. Web-building species were seldom collected on telephone poles, suggesting that they depend on the greater habitat complexity provided by DWM. In contrast, hunting spiders did not distinguish between telephone poles and logs. 5,Fewer spiders and a less diverse fauna utilized elevated compared to ground-level wood. Additionally, Detrended Correspondence Analysis revealed that the spider community from elevated wood was distinguishable from the spider community from ground-level wood, and from the forest floor spider community. [source]