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991.
文章介绍了我国木材科学的发展现状、木材科研体系和条件装备,以及国际合作和学术交流情况;讨论了我国木材科研面临的任务和机遇;提出了我国木材科学近期和最终战略目标;以及近期应优先发展的研究领域和重点课题。  相似文献   
992.
云南CDM林业固C项目的可行性研究   总被引:2,自引:0,他引:2  
通过对《联合国气候变化的框架公约》和《京都议定书》中一些与林业相关的条款及CDM林业固C项目作了简要介绍,结合云南的具体情况,对CDM林业固C项目在云南开展的可行性作了分析。结果如下:云南有开展林业CDM项目的良好条件,可促进生态效益补偿制度的建立,将有力促进云南省林业发展与生态建设;建议开展云南林业的固C效益与固C潜力,固C造林技术与模式,国际认可的林业CDM项目技术、程序与方法等研究。应积极实施林业CDM项目试点,开展国际合作,培养相关人材,通过国家相关部门积极申报林业CDM固C项目。  相似文献   
993.
Poplar is one of the dominant tree species for the establishment of fast growing plantations in Shandong Province.Eighteen poplar clones belonging to Populus aigeiros section were introduced from Italy, Turkey and domestic regions. Populus deltoides cv. ‘Lux‘ 1-69/55 (1-69), which was widely used in Shandong Province, China, was taken as control clone (1-69).Following a randomized complete block design, seedling test and controlled afforestation trials were carried out at Juxian County,Caoxian County and Laiyang City. The results showed that the poplar clone (Populus x euramericana cv. ‘102/74‘), namely 102/74, performed well both in terms of adaptability and growth rate. The mean height of 13.9 m (H), diameter at breast height of 18.0 cm (DBH) and volume growth of 0.1445 m3 (V) were 2.2 %, 21.6% and 52.9% higher than those of 1-69 (CK), respectively,at the age of 5 years at three experimental sites. Moreover, the clone can be propagated easily and showed high resistance to poplar disease, pest as well as salinity and had longer growing period. Furthermore, wood basic density and fiber length of new poplar clone (102/74) were as same as 1-69 (CK). It was concluded that the selected clone (102/74) was ideal for the estab-lishment of fast-growing poplar plantations, especially for the pulpwood plantations in Shandong Province.  相似文献   
994.
神农架地区珍衡植物沿河岸带的分布格局   总被引:2,自引:0,他引:2  
Due to the importance of riparian zone in maintaining and protecting regional biodiversity, increasingly more ecologists paid their attentions to riparian zone and had been aware of the important effects of riparian zone in basic study and practical management. In this study, 42 sampling belts (10 m×100m) parallel to the bank of Xiangxi River at different elevations in Shennongjia Area were selected to investigate the riparian vegetation and rare plants. 14 species of rare plants were found distributing in riparian zone, accounting for 42.4% of the total rare plant species in Shennongjia Area. The main distribution range of the 14 rare plant species was the evergreen and deciduous mixed broadleaved forest at elevation of 1200–1800 m, where, species diversity of plant community was the maximum at the moderate elevation. The analysis of TWINSPAN divided the 14 rare species into 3 groups against the elevation, namely low elevation species group, moderate elevation species group, and high elevation species group. The analysis of DCA ordination showed similar results to that of TWINSPAN. In the paper, the authors discussed the reasons forming the distribution pattern of rare plant species, and pointed out that the important function of riparian zone on rare plant species protection. Foundation item: This project was supported by National Natural Science Foundation of China (NSFC39970123), and Changbai Mountain Open Research Station, Chinese Acadamy of Science. Biography: JIANG Ming-xi (1965-), male, associate professor in Wuhan Institute of Botany, Chinese Academy of Sciences, Wuhan 430074, P. R. China Responsible editor: Chai Ruihai  相似文献   
995.
Relative windspeed reduction was measured behind nine relatively narrow, homogenous tree windbreaks with porosities between 0.13–0.33, and behind 28 combinations of model stubble barriers representing 25 different optical porosities (0.00–0.80). The optimum porosities observed were 0.25 and 0.13 for tree windbreaks and stubble barriers respectively. Based on the relationship between windbreak structure (optical porosity) and wind reduction, the chief indices for determining spacing interval, i.e., the windbreak structure index (δ) and the parameter of microclimate, represented by the problem wind (L rp ), were determined. Additionally, investigations on shelterbelt trees were carried out, and stem-analysis techniques were used, to develop a method for determining the mature height of tree windbreaks (H 0). Optimal spacing intervals between windbreaks could be predicted from the indices of a given windbreak structure, percentage of reduction of windspeed desired and tree growth model. A hypothetical example for determining the spacing interval of principal poplar windbreaks is given at the end of this paper. The results can be applied not only to tree windbreak design but also to other plant materials and artificial barriers for wind protection. Foundation item: This study was supported by Innovation Research Project of Chinese Academy of Sciences Biography: ZHU Jiao-jun (1965-), male, Ph. Doctor, PhD advisor. Professor of Institute of Applied Ecology, the Chinese Academy of Sciences, China, Scholar researcher of Faculty of Agriculture, Niigata University, Japan. Responsible editor: Song Funan  相似文献   
996.
蒋明亮 《林业科学》2001,37(4):107-110
百菌清(CTL)、氨浴季铵铜(ACQ)、氨溶柠檬酸铜(ACC)处理马尾松(Pinus massoniana)、毛白杨(Populus tomentosa)后对木材尺寸稳定性及MOE/MOR的影响本文进行了研究。结果表明,除剂量11.48kg/m^3的百菌清处理的毛白杨外,以上防腐剂处理试材后吸水至饱和时的尺寸稳定性与对照相比有不同程度的增加,幅度为3.9%-28.05;各处理对抗弯弹性模量(MOE)影响幅度不大,其中对于马尾松,MOE差异不明显,对于毛白杨,各处理对MOE稍有增加(百菌清乳剂处理除外),幅度6.3%-8.1之间。各制剂处理马尾松、毛白杨后对抗弯强度(MOR)影响不明显。  相似文献   
997.
我国50~60年代初期,林业部综合队曾编制红松(Pinus koraiensis Sieb.et Zucc.)、云杉(Picea spp.)、马尾松(Pinus massoniana Lamb.)、兴安落叶松(Larix gmelini(Rupr.)Rupr.)、白桦(Betula platyphylla Suk.)等树种材种出材量表,70~80年代各省(区)市、规划院、科研等单位对杉(Cunninghamia lanceolata Hook.)、落叶松、山杨(Populus davidiana  相似文献   
998.
降低负离子空气净化器的臭氧排放量,保护人们免受臭氧的伤害,可以在传统净化器的基础上增加紫外线除臭氧和催化剂除臭氧。臭氧很不稳定,吸收254 nm波长的紫外线后,分解为氧气。高效臭氧分解催化剂能在室温下将臭氧分解为氧。普通负离子空气净化器会释放超标的臭氧,其浓度高达205 ppb,而加入除臭氧装置的新型净化器则释放的臭氧很少,使其浓度控制在19 ppb之内。低臭氧型负离子雾霾空气净化器能有效地清除自身产生的臭氧,性能更优,适合在室内使用。  相似文献   
999.
通过对20个杨树无性系的根系生长进行的比较及聚类分析研究,结果表明:20个杨树无性系不定根总长度和数量均具有较大的差异,其中,中驻1号不定根总长度最长,达到35.6 m,其次是 NL351、T26和中驻6号,最小的为109,仅为15.4 m。数量最大的也是中驻1号,共65根;中驻6号、W07和 I107次之;最小的为 W03和109,均为24根。基部直径在2 cm 以下的不定根占不定根总数量的60%~80%;聚类分析将20个杨树无性系分成6类。  相似文献   
1000.
试验通过实时定量PCR和Western blot技术,检测重金属铜、镉单一及联合急性暴露后鲤肝脏中Hsp60基因和蛋白水平。鲤随机分为7组,两个Cu2+处理组(0.05 mg/l和0.1 mg/l),两个镉处理组(0.63 mg/l和1.26 mg/l),两个混合处理组(0.045 mg/l和0.09 mg/l)和对照组。结果表明铜、镉单一及联合急性暴露对鲤有毒性作用,经过96 h的暴露,除混合低浓度组之外,其余各组肝脏中Hsp60基因表达水平显著提高(P0.05)。受重金属暴露的影响,初期鲤肝脏中Hsp60蛋白水平下降,随着时间推移,蛋白水平逐渐上升,混合低浓度组显著高于对照组水平(P0.05)。  相似文献   
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