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1.
Glycerol stearate was synthesized by esterification with non-toxic,inexpensive glycerol and stearic acid.The composite of glycerol stearate and Pinus radiata wood was prepared by vacuum impregnation.By Fourier transform infrared(FTIR)analysis,there was the generation of new C=O stretching vibration band of glycerol stearate in comparison with stearic acid.This confirms that glycerol stearate was successfully synthesized.The weight gain,FTIR spectrum and morphological analyses of the composite indicate that glycerol stearate was impregnated into the interior lumina of the cells.Thermal analysis showed that the maximal degradation temperature of the composite was 42℃higher than untreated wood.Contact angle images indicated that the value of the composite was134.2°.Hydrophobicity(the repulsion of water)of the composite was stronger than glycerol stearate,which a large number of hydroxyl of wood reacted with the oxygen-containing groups of glycerol stearate,improved hydrophobicity and thermal stability,thereby enhancing the potential application of P.radiata wood.  相似文献   

2.
辐射松(PinusradiataD.Don)原产于加利弗尼亚海岸,被引种到世界各地,现在是南半球主要的人工林造林树种。1990年以来辐射松被引种到长江上游四川省阿坝州的干旱河谷地区,幼树的成活和早期生长表现良好。本文的主要内容包括:辐射松在原产地和引种地的生长情况,种源和遗传上的差异,环境限制因子和辐射松的气候生境,病虫害,引种不成功的经验教训以及辐射松在生态恢复中的应用。文中还简述了辐射松在阿坝干旱河谷地区的早期生长情况,列举了在长江上游干旱河谷地区引种辐射松可能遇到的问题以及所需开展的研究。图4表5参90。  相似文献   

3.
四川阿坝辐射松引种长期森林健康风险初步评估   总被引:2,自引:0,他引:2  
Pinus radiata was introduced to the summer rainfall environments of Sichuan Province, China in the 1990s as a part of an afforestation pmgram for soil and water conservation in the arid and semi-arid river valley area of Aba Prefecture. Within this region a total area of 26 000 ha have been identified through climate matching as suitable and a further 63 000 ha potentially suitable for environmental plantings of P. radiata. The plantations are being established in widely separated small patches on steep and degraded slopes along the dry river valley The newly introduced P. radiata are exposed to two kinds of forest health risks: they may be attacked by (a) indigenous pathogens and pests against which they may not possess any resistance or (b) by inadvertently introduced foreign pests or pathogens. This paper presents a survey of the potential damaging pests and a preliminary assessment of forest health risks facing the P. radiata plantations over a much longer timeframe than the initial phase of introduction and early plantation establishment. An empirical appmach was adopted to evaluate forest health risks by a combination of literature review, examination of historical records of pest and disease outbreaks in the surrounding conifemus forests, field surveys and inspections, specimen collection and identification, and most importantly, expert analysis of the likelihood of attack by specific pests and pathogens and the subsequent impact of such attacks. The assessment identified some specific forest health risks to the long-term success of P. radiata introduction in this area. These risks are closely associated with the indigenous pests and pathogens of the two native pine species, P. tabulaeformis and P. armondii since these pests and pathogens are considered more likely to establish on P. radiata over time. Exotic pests and pathogens are of a quarantine concern at present. Based on the results of assessment, recommendations are pmvided to improve forest vigour and to reduce the forest health risks pos  相似文献   

4.
Abstract

Economic weights are needed for genetic selection to weigh different traits in multitrait breeding. The aim of this study was to develop, for commercial forest species, a model for estimating economic weights of survival relative to volume production per unit area. The model takes the patchiness across a stand and the polygenic nature of the factors influencing survival into account and consists of three submodels. The first submodel calculates volume production and a patchiness coefficient, using a production area that is divided into smaller units or production cells. The patchiness coefficient is defined in the model as the variance of survival between the production cells. The second submodel calculates volume production as a function of survival and the patchiness coefficient. The third submodel is a threshold model, which transforms the genetic change in survival from the observable scale to the underlying (liability) scale, thus providing a measure of economic weight. The model behaviour was studied using growth functions for Pinus sylvestris L. in northern Sweden. Both the absolute value of survival and its patchiness coefficient affected the projected production per unit area. When survival was higher than 50%, the relative economic weight of survival increased with decreasing survival and an increasing patchiness coefficient. The relative economic weight of survival was found to be insensitive to changes in site index and harvesting age, but was clearly affected by different initial stand densities.  相似文献   

5.
松材线虫病抗性马尾松苗木的选育   总被引:2,自引:1,他引:1  
营建现地测定林在松材线虫抗性育种过程中是一项非常重要的部分,分析测定林的生长特性及受害情况能够指导抗性种子园的改良.阐述了采种母树、播种育苗、人工接种测定、测定苗木选拔以及营建测定林.经二次测定后的苗木抗性水平均超过火炬松,4 a生树高年生长量为56 cm,根径、胸高直径等均优于普通马尾松,目前没有出现枯死个体.  相似文献   

6.
在早年营造的针叶混交林中,由于树种的遗传性不同,红松处于被压状态,营养生长和生殖生长受到严重抑制。本文分析了人工针叶混交林改建林分和未改建林分红松球果产量与经济效益的差异,球果产量2者相差33.1倍,产值2者相差48.6倍。说明通过疏伐改建,培育红松果材兼用经济林是可行的。  相似文献   

7.
抗松材线虫病马尾松无性系种子园营建技术   总被引:1,自引:0,他引:1  
松材线虫病是危害松属树种的毁灭性病害,危害严重、防治困难。安徽省从2001年开始从疫区和非疫区的马尾松林分中选择324株抗病优树以及部分广东、广西种源,通过嫁接繁殖和人工接种松材线虫的方法进行无性系抗病性测定。2011年利用筛选出的68个家系的89个高抗无性系营建了1.6 hm2抗松材线虫病马尾松无性系种子园。各家系成活率90.9%~100%,平均成活率93.6%。  相似文献   

8.
With the analytical tool: Frankfurt Harvested Wood Products (HWP) Model, carbon stocks and carbon stock changes of HWP, either in USE or in LANDFILLS, have been evaluated from the readily available statistical data base of the FAO, FAOSTAT, on the wood commodities: “Sawnwood and Wood-based Panels” and the paper commodities: “Paper and Paperboard”. Essential differences have been found between the individual 15 EU countries in the comparison of the Stock Change Approach and the Production Approach, as well as in the comparison of the stock changes of HWP with the National Greenhouse Gas (GHG) budgets. The stock changes for the HWP in USE within the EU-15 Community have been calculated to be 10.83 Mt C/a (39.71 Mt CO2/a) based on the Stock Change Approach and 9.81 Mt C/a (35.97 Mt CO2/a) for the Production Approach, respectively. These numbers can be compared to the total GHG Inventory of the EU-15 of 4,095 Mt CO2 equivalents, including all six Kyoto gases, which shows that the carbon sequestration of HWP in USE is of the order of 1% relative to GHG Inventory. The GHG balance for the carbon stock changes of HWP in LANDFILLS is of similar magnitude as for the HWP in USE, and therefore a sink when methane outgasing is disregarded. However, when methane outgasing is considered, which is formed as a 1:1 mixture with CO2 under the prevailing anaerobic conditions the GHG balance results in minus 10.0 Mt C equivalent/a and minus 10.6 Mt C equivalent/a for the Stock Change Approach and the Production Approach under the parameters chosen in this study. Presented in Dublin, October 6–9, 2004, COST-21 Plenary Session.  相似文献   

9.
Browne  R.D.  Davidson  C.G.  Enns  S.M.  Steeves  T.A.  Dunstan  D.I. 《New Forests》2001,22(3):229-237
Foliar applications of benzyladenine (BA) wereinvestigated as a potential means forenhancing development of proliferated dwarfshoot (pds), which may serve as stem cuttingmaterial for asexual propagation of young jackpine seedlings. BA application in combinationwith pruning promoted pds production. Potential production of 30–40 shoots per BAtreated plant were obtained within 6 monthsfrom sowing of seed, compared to 14–17 forpruned controls (no BA application) in thesame time period. The BA treatment thatresulted in the highest number of pds variedwith the frequency of BA application. Higherconcentrations of BA generally resulted ingreater numbers of pds. Increasing BAconcentration and frequency of applicationreduced rooting capacity of cuttings as wellas lengths of pds. The optimal BA treatmentsfor both total pds production and high rootingwas found to be BA applied singly at 62.5 or125 mg/l or applied twice at 31.2 or62.5 mg/l. The potential utilization of BAtreatments in operational asexual propagationprocedures of jack pine is discussed.  相似文献   

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