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1.
The effect of addition of Acacia mangium bark powder on the thermosetting processes of two commercial phenol resins, PF-A and PF-B, was examined by bond strength
test, torsional braid analysis, and differential scanning calorimetry. When the bark powder was added to PF-A, the bond strength
of plywood pressed at 110°C increased and was comparable to that of plywood pressed at 120 and 130°C. However, when the bark
powder was added to PF-B, the bond strength of plywood pressed at 110°C was still lower than that of plywood pressed at 120
and 130°C. The relative rigidity and loss tangent of PF-A cured with the bark powder obtained by heating at 100°C were comparable
to those at 120 and 140°C, and the reaction enthalpy was increased by bark powder addition. In contrast, chemical reactions
for cured PF-B were not enhanced by bark powder addition. 相似文献
2.
Stability analyses to evaluate site–family interaction for tree height at 15 years old were conducted in trials of open-pollinated families of hinoki (Chamaecyparis obtusa Endl.) plus trees established in the Honshu and Shikoku area of the Kansai Forest tree breeding region, Japan. The Honshu area included 103 sites (226 families), and the Shikoku area included 27 sites (62 families). Analyses of variance indicated that the interaction between site and family was not significant in the Honshu area, whereas in the Shikoku area the interaction was significant. The stability analyses regressed the family–site means against site means. The linear regression analysis was carried out using the data for 164 families that were tested at five or more test sites from the 130 test sites. Approximately 93% of families had values of linear regression coefficient that were not significantly different from unity. These results suggest that almost every open-pollinated family of hinoki plus trees have average stability and are equally well adapted to good and poor sites. The differences in the reaction of a family to site productivity are not the main causes of the interaction. 相似文献
3.
4.
Eduardo Somarriba 《Agroforestry Systems》2012,84(1):1-9
Acacia pennatula trees are the most conspicuous woody species in the pasturelands of the Nature Reserve Mesas de Moropotente, Estelí, Nicaragua.
Cattle ranchers keep A. pennatula because it produces fence posts, forage (pods) and firewood. A population projection matrix model was developed to: (1) estimate
the sustainable harvest (H) of fence posts at different tree population densities, (2) explore the range of recruitment (R),
and survival and growth of both saplings and small poles compatible with current population density, and (3) determine how
much carbon is stored in the soil-pasture-tree system. Acacia pennatula trees take 40 years to reach H size (D30 ≥ 30 cm). Estimated sustainable H from current tree population density is 1.8l7 trees ha−1 year−1, yielding 2.8 large and 11.2 regular size fence posts ha−1 year−1. This annual output easily satisfies the needs of a typical 100 ha cattle ranch in the study area. Current population density
is congruent with very low R (<100 saplings ha−1 year−1), very low survival rates (<0.30%) and/or retarded D30 growth of saplings and small poles. Total carbon in tree biomass was only 37 Mg ha−1. Cattle ranchers have learned to harness the invasive nature of the species to obtain valuable tree products for farm use
or sale. 相似文献
5.
Maha A. Shoaib Mahmoud F. Mahmoud Nagla Loutfy Mohamed A. Tawfic Marek Barta 《Journal of pest science》2010,83(1):27-32
In the laboratory, a commercial neem-based insecticide—Nimbecidine®—was evaluated as a potential pest management tool for the terrestrial snail, Monacha obstructa (Pfeiffer, 1842) (Hygromiidae). Effects of different concentrations of the botanical insecticide on food consumption and egg hatchability of the terrestrial snail were studied. Generally, food consumption of immature and adult snails decreased as the concentrations of Nimbecidine® increased. At the highest concentration (10 ml/l), the snails avoided contacting with food completely. The food intake of immature individuals was significantly (p < 0.05) more affected by the Nimbecidine® treatment (at 1.25 ml/l) than that of adults. LC50 of Nimbecidine® for the treated eggs was 2.18 ml/l, and eggs failed to hatch at concentration of 10 ml/l. Nimbecidine® showed sufficient biological activity against the food consumption and eggs viability of M. obstructa, thus the preparation has a potential to protect field crops from this pest snails. 相似文献
6.
Understanding the relationship between tree height (H) and diameter at breast height (D) is vital to forest design, monitoring and biomass estimation. We developed an allometric equation model and tested its applicability for unevenly aged stands of moso bamboo forest at a regional scale. Field data were collected for 21 plots. Based on these data, we identified two strong power relationships: a correlation between the mean bamboo height (H m) and the upper mean H (H u), and a correlation between the mean D (D m) and the upper mean D (D u). Simulation results derived from the allometric equation model were in good agreement with observed culms derived from the field data for the 21 stands, with a root-mean-square error and relative root-mean-square error of 1.40 m and 13.41 %, respectively. These results demonstrate that the allometric equation model had a strong predictive power in the unevenly aged stands at a regional scale. In addition, the estimated average height–diameter (H–D) model for South Anhui Province was used to predict H for the same type of bamboo in Hunan Province based on the measured D, and the results were highly similar. The allometric equation model has multiple uses at the regional scale, including the evaluation of the variation in the H–D relationship among regions. The model describes the average H–D relationship without considering the effects caused by variation in site conditions, tree density and other factors. 相似文献
7.
Thus far, measurements and estimations of actual evapotranspiration(ET) in extremely arid areas are still insufficient. Based on successive observations from June–September 2014, we simulated ET of a Populus euphratica Oliv. forest during the growing season in an extremely arid region of northwest China using the Shuttleworth–Wallace(S–W) model. Simulated ET values were compared to those of the eddy-covariance(EC) method on a 1 h interval. With a root mean square error(RMSE),relative error(RE) and mean absolute error(MAE) of0.192, 3.100 and 0.165 mm h-1, respectively, model performance was not satisfactory. In particular, on days with strong winds(Sep. 11–13), deviations between simulated and observed ET values increased to 0.275, 0.878 and0.251 mm h-1, RMSE, RE and MAE respectively. These values were significantly greater than those in other study periods and were most likely owing to sharp increases in wind speed. As a result, there were substantial advective effects, which is not consistent with the assumption of the S–W model that there are no advective effects or mesoscale circulation patterns induced by surface discontinuities. 相似文献
8.
Mayumi Sato Kazuto Seki Kazuhito Kita Yoshinari Moriguchi Makoto Hashimoto Keita Yunoki Masao Ohnishi 《Journal of Wood Science》2009,55(1):32-40
The diterpene compositions in the bark of branches were investigated for two families of the F1 hybrid, Kurile larch (Larix gmelinii var. japonica Pilg.) × Japanese larch [Larix kaempferi (Lamb.) Carr.] (hereafter F1) and their parents clones. 13-Epimanool, larixol, larixyl acetate, 13-epitorulosyl acetate (not detected in L. gmelinii var. japonica), isopimaric acid, abietic acid, dehydroabietic acid, and neoabietic acid were detected. Larixol and abietic acid represented
more than 50% of the diterpene content in L. gmelinii var. japonica and L. kaempferi, respectively. Larixol and abietic acid were the predominant diterpene components in the F1, and the proportions of these diterpenes were between those of the parental species. Therefore, the diterpene compositions
in the F1 were hereditarily infl uenced by their parents. The ratios of labdane, pimarane, and abietane diterpenes suggested that the
main diterpene biosynthesis pathway in L. gmelinii var. japonica was from copalyl diphosphate (CDP) to labdane-type diterpenes, and that in L. kaempferi was from CDP to abietane-type diterpenes via pimarane type. Furthermore, linear discriminant analysis suggested that the
diterpene contents are effective indices for the discrimination of the hybrid seedlings.
Part of this article was presented at the Annual Meetings of the Japan Society for Bioscience, Biotechnology, and Agrochemistry
in Kyoto, March 2006, and in Tokyo, March 2007 相似文献
9.
Azize Toper 《Journal of pest science》2002,75(4):103-104
The purpose of this study is to investigate the biology of Cryphalus piceae (Ratz.) (Col., Scolytidae) living in Abies bornmülleriana (Mattf.) in fir forests in the Western Black Sea region in Turkey. The dates of swarming, tree attack, egg-laying, and different stages of development are given. The species had two generations per year. 相似文献
10.
Newly recorded species of the genus Isohypsibius （Tardigrada; Hypsibiidae） from China 总被引：9，自引：0，他引：9
This paper reports two newly recorded species, lsohypsibius lunulatus Iharos, 1966 and lsohypsibiusprosostomus Thulin, 1928, of the genus lsohypsibius （Tardigrada; Hypsibiidae） from China. The specimens of lsohysibius lunulatus were collected from Taibai Mt （34°18′N, 107°42′E） at 2,500 m a.s.1, and those oflsohypsibius prosostomus from Taibai Mt （34°10′N, 107°35′E） at 2,000 m above sea level. All specimens are deposited at the College of Life Sciences, Shaanxi Normal University, China. A key to the Chinese species of lsohypsibius was also given. 相似文献
11.
Indigenous management of tropical forest ecosystems: the case of the Kayapó indians of the Brazilian Amazon 总被引：1，自引：0，他引：1
Darrell Addison Posey 《Agroforestry Systems》1985,3(2):139-158
The Kayapó Indians of Brazil's Amazon Basin are described as effective managers of tropical forest, utilizing an extensive inventory of useful native plants that are concentrated by human activity in special forest areas (resource islands, forest fields, forest openings, tuber gardens, agricultural plots, old fields, and trailsides). Long-term transplanting and selection of plants suggest semi-domestication of many species. The overall management strategies of forest also includes many manipulated animal species (birds, fish, bees, mammals) utilized as food and game. Forest patches (apêtê) are created by Indians from campo/cerrado using planting zones made from termite and ant nests mixed with mulch: formation and development of these is briefly discussed, including the implications for new ideas concerning reforestation and campo management. Finally an integrative cognitive model is presented showing the relationships between variants of forest and savanna recognized by the Kayapó. Indigenous knowledge of subtle similarities between conceptually distinct ecological units in the model allows for the interchange of botanical material between microclimates to increase biological diversity in managed areas. It is suggested that indigenous knowledge is extremely important in developing new strategies for forest and campo/cerrado conservation, while improving productiveness of these ecological systems. Such knowledge is not only applicable for Amazônian Indians, but also has far-reaching implications for human populations throughout the humid tropics.This is a preliminary survey of indigenous management strategies that is generated as a part of the Projeto Kayapó , an interdisciplinary ethnobiological research project funded by the Conselho Nacional de Desenvolvimento Científico e Tecnológico (Brazilian National Council for Scientific and Technological Development) and the World Wildlife Fund. I would like to thank Drs. Gerhard Gottsberger and Anthony Anderson for their assistance in collecting plants that are currently being identified to supply more complete data on Kayapó subsistence. I also wish to thank FUNAI (Fundaão Nacional do Índio) for their assistance and support, as well as FAB (Fora Aérea Brasileira) and VOTEC for providing some transportation to/from Gorotire, and the Unevangelized Field Missions for their assistance in providing communication and acquiring supplies. 相似文献
12.
13.
Yoshie Terashima 《Journal of Wood Science》2013,59(1):80-87
An unidentified Fomitiporia sp. causes severe white-rot on stems of a cultivar “Sanbu-sugi” of the Japanese cedar, Cryptomeria japonica. The influence of the fungus on tree health and wood properties was determined. Bark from dead branches and xylem from living branches contained more glucose than bark from living branches and xylem from dead branches. Tree heights at which annual rings were disconnected were 2, 4 and 6 m at ages 37, 15 and 24 years old, respectively. The pH values of damaged parts were lower than those of non-damaged parts, and the damaged parts were clearly identified using bromocresol green solution. Weight loss of sapwood during 60 days of fungal degradation was 1.4 %, which was less than that by a saprophyte, Trametes versicolor. The amount of polyphenols in the heartwood from damaged tree stems was less than that from non-damaged stems. Degraded parts were less stiff than the non-degraded sapwood as measured with a wood-decay tester, Pilodyn. Our observations indicate that damaged stems are chemically and physically inferior to non-damaged stems. 相似文献
14.
Two newly recorded species of the genus Hypsibius （Tardigrada; Hypsibiidae） from China 总被引：3，自引：0，他引：3
This paper reported two newly recorded species,Hypsibius convergens Urbanowicz,1925 and Hypsibius hypostomus Barto(s),1935,of the genus Hypsibius (Tardigrada; Hypsibiidae) from China.Both species were collected from Taibai Mt,Shaanxi Province.All specimens are deposited at the College of Life Sciences,Shaanxi Normal University,China. 相似文献
15.
We derived an allometric model of the height–diameter curve for even-aged pure stands, which was a modification of the earlier
model proposed by Inoue (2000a). An individual-dependent allometric equation was used as the height–diameter curve. Using
the discriminant analysis method, all trees composed of a stand were stratified into upper and lower trees. It was assumed
that both relationships between mean tree height H
m
and upper tree height H
u
and between mean DBH D
m
and mean DBH of upper trees D
u
could be described by the time-dependent allometric power equations. The height–diameter curve showed an average relationship
between tree height and DBH of a given stand at a given time, and hence it could be assumed that the height–diameter curve
contained two points (D
m
, H
m
) and (D
u
, H
u
). With these assumptions, we derived an allometirc model of height–diameter curve, which allowed the coefficients of the
curve to be estimated from mean tree height and mean DBH. The proposed model was fitted to Japanese cedar (Cryptomeria japonica D. Don) data. The error ratio of the allometric model ranged from 2.254% to 13.412% (mean = 6.785%), which was significantly
smaller than that of the earlier model. When the error of mean tree height was ±1.0 m or less, the effect of the error of
mean tree height on the error ratio was comparatively small. This suggested that the error of ±1.0 m in mean tree height could
be accepted in the estimation of height–diameter curve using the allometric model. These features enable us to combine the
allometric model with Hirata’s vertical angle-count sampling or growth models. In conclusion, the allometric model would be
one of the most practical and convenient approaches for estimating the height–diameter relationship of even-aged pure stands. 相似文献
16.
We used energy dispersive X-ray fluorescence (EDXRF) to determine the seasonal variation of selected trace elements (Cr, Mn, Zn, Cu, Se and Fe) and some potential toxic elements (Cd, Pb and Br) in Juniperus thurifera subsp. africana Maire (Cupressaceae) a rare medicinal tree, growing indigenously in Aurès Mountains of Algeria. The precision of the results was assessed by analyzing the certified reference material IPE44 (WEPAL) grass leaves. Results showed J. thurifera was characterized by high Cr and Mn contents. During autumn and winter mineral concentrations were higher in general. The levels of Cr, Se and Mn were higher during autumn and winter than during spring and summer. Zn contents were higher during summer than in other seasons. Cu content did not vary by season. The potential toxic elements in J. thurifera (Pb > Cd > Br) were below the permissible limits recommended by the Joint WHO/FAO guidelines except for Pb in autumn and winter. 相似文献
17.
18.
Polymorphism analysis of the 5 portion of 26S rDNA from 34 Pleurotus strains (12 intersterility groups) collected mainly from Asia was performed. By combining the restriction fragment length polymorphism (RFLP) patterns obtained from digestions with seven restriction enzymes, the 34 Pleurotus strains were assigned to 11 RFLP types. Ten RFLP patterns corresponded with biological species, but one pattern was found in intersterility groups I (P. ostreatus complex), II (P. pulmonarius complex), and VIII (P. eryngii). The phylogenetic tree suggests that Pleurotus species have evolved in two patterns based on 26S rDNA RFLP data. One major cluster comprising the P. ostreatus clade is separated by relatively short branches, suggesting that the P. ostreatus complex, the P. pulmonarius complex, P. eryngii, and P. nebrodensis (intersterility groups I, II, VIII, and IX, respectively), share a recent common ancestor. RFLP data did not distinguish the species in the intersterility groups I, II, and VIII. The other major cluster apparently divided into five sublevel clusters in early stages of evolution and these clades split into terminal nodes in late stages of evolution: the P. calyptratus-salmoneostramineus clade, the P. cornucopiae-ulmarius clade, the P. dryinus clade, the P. corticatus clade, and the P. cystidiosus-smithii clade. 相似文献
19.
Two newly recorded species of the genus Itaquascon （Tardigrada; Hypsibiidae） from China 总被引：4，自引：0，他引：4
This paper reports two newly recorded species, Itaquascon placophorum Maucci, 1972 and Itaquascon umbellinae Barros, 1939, of the genus Itaquascon (Tardigrada; Hypsibiidae) from China in the first time. The specimens of Itaquascon placophorum were collected from Tsinling Mountains (33°28'N, 108°29'E) at 2,040 m above the sea level and those of Itaquascon umbellinae from Taibai Mt. (34°21'N, 107°39'E) at 1,500 m above the sea level. All specimens are deposited at the College of Life Sciences, Shaanxi Normal University, China. 相似文献
20.
LiJingwen ZhangHuarong LiJunqing 《中国林学(英文版)》2003,5(3):6-9
Random amplified polymorphic DNA (RAPD) markers were used to analyze genetic variation of Podocarpus imbricatus in Hainan Island and Mainland of China. Two populations of Dacrydium pierrei were used as comparison materials. Both Podocarpus imbricatus and Dacrydium pierrei showed a low level of genetic diversity. However, Podocarpus imbricatus showed higher genetic diversity and higher population differentiation than Dacrydium pierrei. The geographic range may affect the geneticdiversity of Podocarpus imbricatus and Dacrydium pierrei signific antly. The UPGMA cluster tree showed that populations of Podocarpus imbricatus in Hainan Island and Guangxi Zhuang Autonomous Region were closer than those in Yunnan Province,indicating possible gene flow between Hainan Island and Guangxi Zhuang Autonomous Region. The young geological history of Hainan Island and the three times of unification and separation between Hainan Island and the Mainland may give the two species more possibilities of gene flow. 相似文献