柳杉木材边材木醋液中的成分研究

用毛细管气相色谱法对日本柳杉木材边材炭化得到的木醋液中的37种成分进行定性和定量分析.结果表明,醇类、酮类、羧酸类、呋喃类、苯酚类及愈创苯酚类是其主要成分.用溶剂萃取-硅胶柱层析法进一步分离处理木醋液,纯化出炭化过程中产生的手性脱水内醚糖-左旋葡聚糖(LGA,1,6-脱水-β-D-葡萄糖),但其不能被毛细管气相色谱法检...     

醋酸水溶液预处理对柳杉木材炭化的影响

杉木(日本柳杉)经醋酸水溶液处理后，重量减少。将处理前后柳杉木材在4℃下进行炭化，得到了木醋液、木焦油和木炭。与未处理材相比，处理材木醋液的收率增加，而木焦油和木炭的收率减少。处理液的醋酸浓度增加后，木醋液和木焦油的收率几乎不变，但木炭的收率稍微减少了。用毛细管气相色谱法对木醋液的成分进行了定量分析。与未处理材相比，处理材木醋液中糠醛(呋喃甲醛)及5-羟甲基糠醛的收量增加，而羧酸类、苯酚类、邻苯二酚、愈创木酚类及麦芽酚的收量几乎不变。当醋酸浓度从0增至3％时，糠醛的收量随着增加，但是当醋酸浓度从3％增至30％时，其收量却几乎不变。     

化学处理对竹材炭化的影响

在竹材进行炭化之前，用化学药液对竹材进行浸泡处理，通过这种处理方式，在相同的炭化压力和温度下，能缩短炭化周期，同时炭化后的竹片纹理清晰，色泽均匀，色差小。     

化学处理对竹材炭化的影响试验

在竹材进行炭化之前，用化学药液“强酸胍类”物质与其他助剂的混合物对竹材进行浸泡处理，在相同的炭化压力和温度下，能缩短炭化周期，同时炭化后的竹片纹理清晰，色泽均匀，色差小。     

水分胁迫对日本柳杉种子萌芽的影响

本文采用配置不同浓度的PEG(聚乙二醇)溶液来模拟土壤自然水势，对日本柳杉种子萌芽实验进行人工水分胁迫处理。结果表明：随着水势的下降，其发芽率在轻度水分胁迫下有所上升，然后降低，随PEG浓度上升到15％时，发芽率、发芽速度、发芽指数、活力指数、芽长等都出现不同程度的降低。而当PEG浓度上升到25％时，则上述指标均受到强烈抑制。结果表明，日本柳杉在轻度干旱胁迫时，具有一定的耐旱性。     

不同岩性土体对日本柳杉生长影响试验初报

通过对黔中地区6种不同岩性土壤进行栽种日本柳杉的实验研究,其初步结果表明,不同岩性土体对日本柳杉的生长发育产生了一定影响。日本柳杉在6种不同土体上的成活率,在煤系砂页岩上较好达88.33%,而在灰质白云岩较差。高生长则在灰质白云岩和煤系砂页岩上长势略好于其它岩性的土壤,但并没有产生显著的差异。地径的生长在不同岩性的土壤上产生了显著差异。     

木醋液在日本落叶松种子催芽处理上的应用

木醋液含天然醋酸、乙醇和多种酚类等有机成分,对种子无毒副作用。应用木醋液对日本落叶松种子进行催芽处理,可以有效地杀灭病菌,保证种子原有品质,种子发芽率、发芽势较常规处理法分别提高6个和5个百分点。     

日本柳杉无性系的引种保存与扦插繁殖

为了引种抗雪压能力强的日本柳杉优良繁殖材料,从日本冬季降雪多的地区引进了52个柳杉无性系.通过就地栽植和假植两种方式进行保存,并开展扦插繁殖、促萌增穗试验.结果表明:提前整地和遮阴保湿是成功保存日本柳杉无性系的关键措施;不同无性系类别间的扦插成活率有差异,用黄心土作基质扦插的效果好于石英砂;截枝法、截干法均能促进枝条萌发,截枝法略优于截干法.     

利用RCR-RAPD法和同功酶分析法日本柳杉无性系的识别方法研究

以日本福岛县林业试验场日本柳杉种子园的 ２４个无性系为材料,利用 ＰＣＲ—ＲＡＰＤ法和同功酶分析法对日本柳杉无性系的识别方法进行了比较研究。结果显示：同功酶法和由７个标记构成的ＲＡＰＤ分析法不能完全识别２４个无性系,用１７个和２７个标记构成的ＲＡＰＤ分析法识别这２４个无性系是可能的;同功酶标记是一种基因型标记,具有稳定性高的特点,适合于分析遗传构造的相似程度,特别适合于群体遗传分析,但是,由于能获得清晰话带的同功酶种类有限,在用于个体识别上比较困难;ＲＡＰＤ标记是一种显性标记,稳定性较差,但只要反应体系和条件稳定,利用ＲＡＰＤ标记正确进行无性系识别是完全可能的。     

炭化处理对杨木声学振动特性的影响

为了探究炭化处理对木材板材声学振动性能的影响和规律,本文对45块白杨试件进行不同炭化温度(170、190、210℃)和不同保温时间(2、3、4 h)的炭化处理。采用了傅立叶变换频振动频谱分析仪(fast Fourier transform,FFT)测定炭化处理前后的杨木密度、比动弹性模量、声辐射品质常数、声阻抗及弹性模量与剪切模量比值的变化规律。结果表明:炭化处理工艺对不同的声学振动参数有不同的影响规律,当处理温度为210℃、保温时间为3 h时,可以较为显著的提高木材综合声学振动性能。     

醋酸水溶液处理对杉树材影响

为了研究醋酸水溶液处理给杉树材重量带来的变化,使用醋酸水溶液对杉树材进行了处理。结果发现处理后杉树材重量的减小量大约等于抽出物的重量,而且随着醋酸水溶液浓度的增加而增加。利用傅立叶变换红外光谱法对处理后的杉树材及抽出物进行了光谱分析。从处理后杉树材的光谱图可以观察到3400cm-1附近的OH伸缩振动及1510cm-1附近的木质素中苯环C=C伸缩振动的吸收强度有增加倾向。从醋酸水溶液抽出物光谱图可以发现用浓度30%醋酸水溶液处理时木质素被溶出。图2表2参6。     

Relationships between blacking phenomenon and norlignans of sugi (Cryptomeria japonica) heartwood III: Coloration of norlignans with alkaline treatment

We investigated norlignan coloration with alkaline treatment to clarify the relationship between the blackening of sugi (Cryptomeria japonica D. Don) heartwood and norlignans in the heartwood. Of the four main norlignans (agatharesinol, sequirin-C, sugiresinol, hydroxysugiresinol) of sugi heartwood, only sequirin-C was clearly colored with alkaline treatment (0.4% potassium hydrogencarbonate solution, pH 8.6). Sequirin-C changed color to deep purple with alkaline treatment. The absorbance spectrum of colored sequirin-C had two peaks (450 and 525nm) and one shoulder (626nm). Coloration began at pH 6.2.). The spectrum of blackened sugi heartwood was similar to that of sequirin-C treated with alkali. A catechol nucleus and a double bond conjugated with a benzene nucleus play important roles in norlignan coloration with alkaline treatment. The number of hydroxyl groups is related to solubility in alkaline solution, and, therefore, whether a norlignan changes color also depends on the number of hydroxyl groups. Based on these results, we concluded that sugi heartwood turns black because sequirin-C, which is readily soluble in alkaline solution and can form a large intramolecular conjugation system when alkalized, is converted to products with a deep purple color as the heartwood is basified.     

Antimicrobial activity of heartwood components of sugi (Cryptomeria japonica) against several fungi and bacteria

Methanol extract of sawdust of sugi (Cryptomeria japonica) heartwood was fractionated with toluene and n-hexane to give solvent-soluble and solvent-insoluble fractions. The n-hexane-soluble fraction showed the most inhibition activity among the fractions against phytopathogenic microorganisms, namely Fusarium oxysporum, Phytophthora capsici, Pythium splendens, and Ralstonia solanacearum. Sandaracopimarinol and ferruginol, isolated from the n-hexane-soluble fraction, showed moderate antifungal activity against the three fungi and strong antibacterial activity against R. solanacearum. The content of sandaracopimarinol (7.07 g/kg based on the dried sawdust) in the heartwood was about twice that of ferruginol. Sandaracopimarinol and ferruginol strongly inhibited the growth of Gram-positive bacteria but did not show inhibitory action against Gram-negative bacteria except for R. solanacearum. The antibacterial effect of sandaracopimarinol was first found in the present study and was stronger than that of ferruginol.     

Estimating individual tree heights of sugi (Cryptomeria japonica D. Don) plantations in mountainous areas using small-footprint airborne LiDAR

Recently, it was shown that individual tree heights could be accurately estimated using small-footprint airborne light detection and ranging (LiDAR) remote sensing. Because most of the areas studied previously were limited to flat terrain, we investigated the accuracy of LiDAR-derived individual tree height estimates for different types of topographical features in mountainous forests with a steeper and more complex topography. Several middle-aged (40–50 years old) sugi (Cryptomeria japonica D. Don) plantations are found in the mountainous regions in Japan; hence, we chose 48-year-old sugi plantations to investigate the accuracy of these estimates. The surveyed area was divided into three types of topographical features; steep slope (mean slope ± SD; 37.6° ± 5.8°), gentle slope (15.6° ± 3.7°), and gentle yet rough terrain (16.8° ± 7.8°). Before estimating tree heights, the number of detected trees within each topographical feature was researched. In each of these terrains, the percentage of trees detected correctly was 74%, 86%, and 92%; the average error between LiDAR-derived and field-measured tree heights was 0.227m, –0.473m, and –0.183m; and the accuracy of the LiDAR-derived tree height estimates, given as root mean square error (RMSE), was 0.901m, 0.846m, and 0.576m, respectively. Consequently, the procedure presented in this study could detect most canopy trees and estimate individual tree heights with an accuracy better than 1m, even in a forest with a mean slope angle of approximately 38°; thus, indicating that small-footprint airborne LiDAR will be a useful tool for accurately estimating the heights of individual canopy trees in sugi plantations in mountainous areas.     

Treatment of sugi （Cryptomeria japonica D.） sapwood with aqueous solution of acetic acid

Sugi sapwood samples were processed with aqueous solution of acetic acid in order to find the response of the weight of sugi sapwood and the treatment of aqueous solution of acetic acid. The result showed that loss of weight for the treated sugisapwood was about equal to yield of extracts from sugi sapwood, and increased with the increment of the concentration of aqueous solution of acetic acid. Fourier transform infrared spectroscopy spectra changes of the treated sugi wood and extracts from sugi sapwood were analyzed by FT-IR spectroscopic technique. Increasing tendency of absorption intensities of the stretching vibration at 3 400 cm^-1 of hydroxyl group (OH) and C=C in lignin stretching vibration at 1510 cm^-1 of benzene ring inlignin were observed from FT-IR of the treated sugi sapwood. From FT-IR spectra of extracts from sugi sapwood by aqueoussolution of acetic acid, the dissolution of lignin was observed during the treatment with 30% acetic acid solution aqueous.     

Potassium distribution in black heartwood of sugi (Cryptomeria japonica) I: Localization in axial parenchyma cells

This is the first report to ascertain potassium location in black heartwood of sugi (Cryptomeria japonica). The objective of this study was to understand the distribution of potassium in sugi black heartwood in connection with anatomical morphology. Scanning electron microscopy with energy dispersive X-ray analysis (SEM-EDXA) was used to investigate the distribution of inorganic elements, especially potassium. In black heartwood, potassium was detected in all tissues (tracheids, ray parenchyma, and axial parenchyma), but its concentrations were different in each xylem tissue. Potassium was particularly accumulated in the droplets in axial parenchyma cells. In addition, calcium was also detected in all tissues. Phosphorus sometimes existed in the granules in ray parenchyma cells. From optical microscopy, the axial parenchyma cells were observed to be arranged in a tangential direction on transverse section and the droplets in these cells were distributed in areas of high ash and green moisture content. For red heartwood, potassium detected by SEM-EDXA was far lower in all tissues than in the black heartwood, while the trend for calcium was the converse. Potassium in axial parenchyma cells was more abundant in black heartwood than in typical pale red heartwood.     

Effect of forest thinning on soil net nitrogen mineralization and nitrification in a Cryptomeria japonica plantation in Taiwan

We investigated the effect of forest thinning on soil nitrogen mineralization, nitrification and transformation in a Cryptomeria japonica plantation at high elevation to provide basic data for forest management. We chose four study plots for control, light, medium and heavy thinning treatment, and three sub-plots for buried bag studies at similar elevations in each treatment plot to measure the net N mineralization and nitrification rates in situ. The contents of soil inorganic N(ammonium and nitrate) were similar between treatments, but all varied with season, reaching maxima in September 2003 and 2004. The seasonal maximum net Nmin rates after four treatments were 0.182, 0.246, 0.303 and 0.560 mg·kg-1·d-1 in 2003, and 0.242,0.258,0.411 and 0.671 mg·kg-1·d-1in 2004, respectively. These estimates are approximate with the lower annual rates of N mineralization for this region. Forest thinning can enhance net N mineralization and microbial biomass carbon. The percentage of annual rates of Nmin for different levels of forest thinning compared with the control plot were 13.4%, 59.8% and 154.2% in 2003, and 0.1%, 58.8% and 157.7% in 2004 for light, medium, and heavy thinning, respectively. These differences were related to soil moisture, temperature, precipitation, and soil and vegetation types. Well-planned multi-site comparisons, both located within Taiwan and the East-Asia region, could greatly improve our knowledge of regional patterns in nitrogen cycling.     

基夜蛾导致黄甜竹退笋规律及防治研究

基夜蛾是黄甜竹林间最重要的害虫,为害率高达90%,且为害严重,退笋率也高达60%～70%。本文在总结前人研究的基础上,初步探讨了出笋时间、退笋时间、出笋率与退笋率的规律性。同时还描述了为害症状、为害规律、蛀食习性,提出一些防治措施与建议,以便指导生产实践。