Rates of fixation in chromated copper arsenate (CCA-C) treated red pine (Pinus resinosa Ait.) and southern pine (Pinus spp) sapwood specimens using retention of 1.5, 2.0, 6.4 kg·m?3 are compared at temperature (T...Rates of fixation in chromated copper arsenate (CCA-C) treated red pine (Pinus resinosa Ait.) and southern pine (Pinus spp) sapwood specimens using retention of 1.5, 2.0, 6.4 kg·m?3 are compared at temperature (T) ranging from 70°C to 50°C and 5 different relative humidity (RH) conditions. The samples were investigated using the expressate method to follow chromium fixation. Red pine fixes faster than southern pine under all 11 post treatment schedules. The fixation rates for both species are not significantly different while the blocks were fixed under 6 fixation/drying schedules that differed only in the order of T/RH conditions applied. The rate of fixation of all samples in any fixation stage were reduced when the blocks were fixed under lower humidity conditions in spite of no change in chamber temperature. Some of this influence can be attributed to the effect of humidity on heat transfer into the wood and cooling of the wood surface.展开更多
Red pine (Pinus resinosia Ait) and southern pine (Pinus spp.) sapwood blocks were pressure treated with CCA-C at retention of 6.4, 2.0, 1.5 kg(m-3 followed by fixation using 11 post-treatment schedules ranging from 50...Red pine (Pinus resinosia Ait) and southern pine (Pinus spp.) sapwood blocks were pressure treated with CCA-C at retention of 6.4, 2.0, 1.5 kg(m-3 followed by fixation using 11 post-treatment schedules ranging from 50-70 (C and 5 different relative humidity conditions. The effect of these post-treatment schedules on fixation rate, chemical leachability and decay resistant once were evaluated to better understand the effects of fixation/drying conditions on leachability and biodeterioration. Southern pine blocks fixes slightly slower than red pine. Fixation of CCA at high temperature high humidity, essential initially fixation at high humidity for fixation/drying schedules, resulted in lower leaching of chromium and arsenic elements than high temperature low humidity or initially fixation at the high temperature low humidity conditions. Copper leaching was indicated no significant difference under 11 fixation/drying conditions for both species. Weight losses for southern pine by Chaetomium globosum was lower than red pine by Gloeophyllom trabeum. There were some different capacities of decay resistance for both species under those post treatment conditions.展开更多
Understanding vertebrate habitat relationships is important to promote management strategies for the longterm conservationof many species. Using a modified drift fence method, we sampled reptiles and compared habitat ...Understanding vertebrate habitat relationships is important to promote management strategies for the longterm conservationof many species. Using a modified drift fence method, we sampled reptiles and compared habitat variables within theWilliam B. Bankhead National Forest (BNF) in Alabama, U.S.A from April 2005 to June 2006. We captured 226 individual reptilesrepresenting 19 species during 564 total trap nights. We used canonical correspondence analysis to examine habitat associationsfor the reptiles sampled and we detected a distinct habitat gradient ranging from sites with greater litter depth and percentcanopy cover to more open sites with greater woody, herbaceous, and coarse woody debris (CWD) coverage, and CWD volume.Little brown skinks Scincella lateralis and eastern worm snakes Carphophis a. amoenus were associated with sites with greaterlitter depth and canopy cover, whereas eastern fence lizards Sceloporus undulatus, copperheads Agkistrodon cnntortrix, and grayratsnakes Pantherophis spiloides were associated with sites possessing greater CWD coverage and volume. We found that disturbancesdue to the southern pine beetle Dendroctonus frontalis were likely important for influencing reptile distributions throughthe creation of canopy gaps and fallen coarse woody debris. Compared to other studies, our modified drift-fence trap techniquewas successful for sampling larger snake species (66 snakes in 564 trap nights). We have also provided detailed schematics forconstructing drift fence array and box traps used in this study .展开更多
The effects of fixation drying conditions on fixation rates and chemical leachab ility were investigated with CCA-C treated red pine (Pinus koraiensis Sieb. )and southern pine specimens at a retention of 6 4 kg·...The effects of fixation drying conditions on fixation rates and chemical leachab ility were investigated with CCA-C treated red pine (Pinus koraiensis Sieb. )and southern pine specimens at a retention of 6 4 kg·m -3 , and under 11 post-treatment schedules ra ng ing from 50～70℃ and 5 different relative humidity conditions. These samples w e re monitored by expressing residual liquid and analyzing it for hexavatent chrom ium content. Samples were subjected to AWPA E11-97 (AWPA 1997) standard leachi n g tests after fixation. Generally, red pine fixed slightly faster than southern pine for most fixation conditions. High temperature, high humidity, fixation co nditions during the fixation/drying schedules resulted in faster fixation and lo wer leaching of chromium and arsenic elements compared to low humidity condition s. Copper leaching showed no significant difference under 11 fixation /drying co nditions for both species. All of the CCA components were leached significantly more in red pine than southern pine. Further work is needed to examine the effec ts of different fixation/drying conditions on leaching from full\|size samples a n d to optimize dry/wet bulb depression for fixation/drying of CCA treated lumber.展开更多
文摘Rates of fixation in chromated copper arsenate (CCA-C) treated red pine (Pinus resinosa Ait.) and southern pine (Pinus spp) sapwood specimens using retention of 1.5, 2.0, 6.4 kg·m?3 are compared at temperature (T) ranging from 70°C to 50°C and 5 different relative humidity (RH) conditions. The samples were investigated using the expressate method to follow chromium fixation. Red pine fixes faster than southern pine under all 11 post treatment schedules. The fixation rates for both species are not significantly different while the blocks were fixed under 6 fixation/drying schedules that differed only in the order of T/RH conditions applied. The rate of fixation of all samples in any fixation stage were reduced when the blocks were fixed under lower humidity conditions in spite of no change in chamber temperature. Some of this influence can be attributed to the effect of humidity on heat transfer into the wood and cooling of the wood surface.
文摘Red pine (Pinus resinosia Ait) and southern pine (Pinus spp.) sapwood blocks were pressure treated with CCA-C at retention of 6.4, 2.0, 1.5 kg(m-3 followed by fixation using 11 post-treatment schedules ranging from 50-70 (C and 5 different relative humidity conditions. The effect of these post-treatment schedules on fixation rate, chemical leachability and decay resistant once were evaluated to better understand the effects of fixation/drying conditions on leachability and biodeterioration. Southern pine blocks fixes slightly slower than red pine. Fixation of CCA at high temperature high humidity, essential initially fixation at high humidity for fixation/drying schedules, resulted in lower leaching of chromium and arsenic elements than high temperature low humidity or initially fixation at the high temperature low humidity conditions. Copper leaching was indicated no significant difference under 11 fixation/drying conditions for both species. Weight losses for southern pine by Chaetomium globosum was lower than red pine by Gloeophyllom trabeum. There were some different capacities of decay resistance for both species under those post treatment conditions.
基金provided by the USDA Forest Service Southern Research Stationthe National Science Foundation
文摘Understanding vertebrate habitat relationships is important to promote management strategies for the longterm conservationof many species. Using a modified drift fence method, we sampled reptiles and compared habitat variables within theWilliam B. Bankhead National Forest (BNF) in Alabama, U.S.A from April 2005 to June 2006. We captured 226 individual reptilesrepresenting 19 species during 564 total trap nights. We used canonical correspondence analysis to examine habitat associationsfor the reptiles sampled and we detected a distinct habitat gradient ranging from sites with greater litter depth and percentcanopy cover to more open sites with greater woody, herbaceous, and coarse woody debris (CWD) coverage, and CWD volume.Little brown skinks Scincella lateralis and eastern worm snakes Carphophis a. amoenus were associated with sites with greaterlitter depth and canopy cover, whereas eastern fence lizards Sceloporus undulatus, copperheads Agkistrodon cnntortrix, and grayratsnakes Pantherophis spiloides were associated with sites possessing greater CWD coverage and volume. We found that disturbancesdue to the southern pine beetle Dendroctonus frontalis were likely important for influencing reptile distributions throughthe creation of canopy gaps and fallen coarse woody debris. Compared to other studies, our modified drift-fence trap techniquewas successful for sampling larger snake species (66 snakes in 564 trap nights). We have also provided detailed schematics forconstructing drift fence array and box traps used in this study .
文摘The effects of fixation drying conditions on fixation rates and chemical leachab ility were investigated with CCA-C treated red pine (Pinus koraiensis Sieb. )and southern pine specimens at a retention of 6 4 kg·m -3 , and under 11 post-treatment schedules ra ng ing from 50～70℃ and 5 different relative humidity conditions. These samples w e re monitored by expressing residual liquid and analyzing it for hexavatent chrom ium content. Samples were subjected to AWPA E11-97 (AWPA 1997) standard leachi n g tests after fixation. Generally, red pine fixed slightly faster than southern pine for most fixation conditions. High temperature, high humidity, fixation co nditions during the fixation/drying schedules resulted in faster fixation and lo wer leaching of chromium and arsenic elements compared to low humidity condition s. Copper leaching showed no significant difference under 11 fixation /drying co nditions for both species. All of the CCA components were leached significantly more in red pine than southern pine. Further work is needed to examine the effec ts of different fixation/drying conditions on leaching from full\|size samples a n d to optimize dry/wet bulb depression for fixation/drying of CCA treated lumber.
