台湾含笑新叶与老叶叶片面积构建成本之比较

为比较新老叶的"质量-面积"异速生长关系和叶片功能性状的差异,以50 a以上的台湾含笑成树为材料,分别测量台湾含笑新老叶的叶片数据。采用减少主轴法拟合叶片干鲜重和面积对数转化数据得到线性模型的参数;用自举分位点法检验新老叶模型参数的差异显著性;使用Tukey's HSD检验对比了新老叶叶片功能性状。结果显示:新老叶的干重与鲜重、鲜重与面积和干重与面积的异速生长指数都不存在显著性差异,但是回归方程的截距项存在显著性差异;除了宽长比不存在显著性差异外,新老叶其余叶片功能性状均存在显著性差异。研究表明:新老叶的异速生长关系都遵从收益递减规律;由于新老叶的叶片功能性状在生长季早期存在显著差异,所以在研究叶片异速生长关系时,建议在夏末新叶的干物质含量基本稳定时取样。     

临泽县小泉子滩防风固沙林及防护林体系效益浅析

对临泽小泉子治沙站营造的防风固沙林及农田防护林进行了观测研究，观测结果表明：在200cm观测高度时，固沙阻沙林内的风速降低了24．0％～55．0％，在150cm的高度时，风速降低了29．1％～55．8％。农田林内在200cm观测高度时，林后15m、30m的距离风速分别降低了28．4％、39．8％，在150cm的高度时，风速分别降低了28．8％、35．0％，在50cm的高度时，风速分别降低了31．0％、43．7％，林后30m比15m的距离风速降低的幅度大。因此，防风固沙林和农田防护林的防风效果非常显著。     

植物喷施灵对白皮松种子发芽的影响

设置了植物喷施灵5种浓度处理,分别为0．325g／L0.650g／L,300g／L,2．600g／L,清水对照;研究了植物喷施灵对白皮松种子萌发的影响。结果表明：植物喷施灵对白皮松种子的发芽效果有显著影响,植物喷施灵的浓度为0．325g／L时,对白皮松种子萌发的促进作用最大,发芽率为77％;浓度为0．650g／L。对提高白皮松种子的发芽势最有利,发芽势为44％。     

不同芸苔素内酯处理对油茶幼龄林生长的影响

为了研究油茶的最佳芸苔素内酯用量,以长林优良无性系为材料,进行采用叶面喷施0.067 mg/L、0.050 mg/L、0.033 mg/L、0.025 mg/L及0.020 mg/L质量浓度芸苔素内酯的试验,在油茶不同生长期调查并测定各项指标,对测量数据进行分析和总结。结果表明:对春梢生长最有利的芸苔素内酯质量浓度是0.067 mg/L;对秋梢生长最有利的芸苔素内酯质量浓度是0.025 mg/L;新叶叶绿度Spad值增加最大的芸苔素内酯质量浓度是0.033 mg/L;老叶叶绿度Spad值增加最大的芸苔素内酯质量浓度是0.050 mg/L;油茶产量最高的芸苔素内酯质量浓度是0.050 mg/L;油茶出籽率最高的芸苔素内酯质量浓度是0.050 mg/L;油茶籽千粒质量最大的芸苔素内酯质量浓度是0.067 mg/L。     

不同氮磷钾含量的施肥配比对半年生杨叶肖槿苗木生长及生理的影响

0,5年生杨叶肖槿盆苗育苗期不同氮、磷、钾含量的施肥配比对其苗木生长及生理影响的试验结果表明：促进其苗高、地茎、叶片数及叶绿素含量4个指标的较优施肥配比为N0．7g·盆^-1、P2O5 0g·盆^-1、K2O0．7g·盆^-1。与对照相比,其苗高提高了1.54倍、地径提高了0．77倍、叶片数增加12．8片、叶绿素含量增加了0．99倍;影响苗木根、茎、叶干重3个指标的较优施肥配比为N0．7g·盆^-1、P2O5 0．7g·盆^-1、K2O0g·盆^-1,其苗木根、茎、叶的干重分别比对照增加了7.00倍、7．66倍、8．54倍;而促进其苗木叶片净光合速率的较优施肥配比为N0．7g·盆^-1、P2O5 0.35g·盆^-1．K2O1．4g·盆^-1,上午10：00时的苗木叶片净光合速率比对照提高2．25μmol／m2·s．在育苗期施肥管理时施用N、P、K3种肥料对杨叶肖槿苗木生长和生理影响的效应不同,以N肥的影响力最大,其次是P,K的影响效应最小。     

苏铁观叶知病及预防

苏铁浑厚挺拔 ,坚硬如铁 ,且喜欢铁质肥料 ,故又称铁树。苏铁喜光、耐荫、耐干旱 ,不耐水湿 ,宜在酸性土中生长。经多年观察 ,总结出根据叶色变化判断病因 ,“对症下药”的莳养经验。一、新叶的叶尖及小叶卷曲、变黄白色而干枯 ,老叶变化不大 ,这是盆土长期较干燥所致。应加强水分管理 ,保证土壤含水量在 4 0 %～ 5 0 %左右。二、新叶上有成片黄白色日灼斑 ,老叶较少 ,这是夏季暴晒所致。高温季节应把铁树置于散射光处 ,早、中、晚各喷一次叶面水。三、新叶失绿、黄化、干枯 ,但叶脉仍为绿色 ,这是缺铁所致。对发病植株应每 3～ 5天喷一次 0…     

苗木喷雾机风送系统优化设计及气流场试验

针对国内多风管苗木喷雾机风送距离短、机型体积与载重量大的问题,对苗木喷雾机风送系统中的多出口装置结构进行优化模拟和试验验证。设计了多排八出口、多排六出口和双排八出口3种多出口装置,采用模拟和试验相结合的方法,得出多出口装置型式对出口风速和风压的影响规律。结果表明:试验与模拟风速数据大致相似,3种装置出口风速试验值和模拟值的拟合优度分别为0.596 6,0.968 8,0.696 3,验证数值模拟方法的可行性;多排六出口装置出口风压最高,平均风压为662 Pa,各出口风压与风速变化趋势基本一致;多排六出口装置出口风速比八出口高,出口风速范围在29.52～34.85 m/s,各出口风速均匀性更好;在风机3 000 r/min转速下,风管出口风速在喷雾距离0～1.5 m范围内衰减较快,在5 m处风速衰减到1.5 m/s左右;在相同风管高度间隔时,风速边界随风管出口数量增多而增大,与出口风速无关;风送系统外流场在4 m距离内风场垂直面的雾滴沉积分布均匀性较好,5 m距离以上均匀性较差。综合考虑喷雾机整机尺寸和承载能力,多排六出口风送系统更合理,气流射程和雾滴沉积分布能满足5 m的作业要求。     

油松枯枝病病原菌生物学特性研究

该文采用室内纯培养的方法,对油松枯枝病病原菌不同的培养基、温度、碳源、pH值进行培养试验,结果显示：PDA培养基最适合病原菌的生长,其次是燕麦片琼脂培养基（OA）、松针煎汁琼脂培养基（PA）和玉米粉琼脂培养基（CA）,在玉米粉琼脂培养基（CA）上几乎不能生长;病原菌对蔗糖碳源利用较好,其次为葡萄糖、D-果糖和乳糖,对麦芽糖的利用最差;菌落在pH5．0～10．0均能生长,在pH5．0～7．0时生长较好,为最适生长范围,pH6．0菌丝生长速度最快;病原菌在10～30℃均能形成可见菌落,20～25℃生长较好,其中25℃为最适生长温度,大于35℃时不能生长。     

马尾松种子园无性系生长结实规律研究

利用马尾松初级种子园17龄以前母树生长结实有关材料，研究母树一般生长结实特点，年龄，密度与产量的关系，以及无性系结实差异规律等几个方面，结果如下：在文本南亚热带红壤区一般经营条件下，马尾松嫁接线树年平均高生长0．7－0．9m，直径生长1．5－1．9cm，冠幅生长0．68－0．70m，初植密度为4m*4m的种子园在7龄以后植株正常生长开始受到抑制，母树的结实量与主枝阳枝的断面总量程紧密的相关，种子园8－10龄平均产种4．1kg/hm2，11－15龄平均产种量10．5kg/hm2,16-17龄平均产种量13．5kg/hm2，同时，对密度与产量，无性系结实差异作了总结分析。     

延平柿DiospyrostsangiiMerr．

落叶灌木,高1-7m;嫩枝、叶、叶柄均被锈色柔毛;小枝无毛或有短毛;冬芽有柔毛。叶纸质,叶基部狭楔形并下延,叶倒卵状椭圆形,长4-9cm,宽1．5-3cm,先端短渐尖,基部楔形,下面淡绿色有伏柔毛,老叶下面中脉上疏生长伏毛外,余处无毛;侧脉每边3-4条;叶柄幼时带红色,长0．3-0．6cm。     

Influence of photosynthetic photon flux density on growth and transpiration in seedlings of Fagus sylvatica

Beech seedlings (Fagus sylvatica L.) were grown in various combinations of three photosynthetic photon flux densities (PPFD, 0.7, 7.3 or 14.5 mol m(-2) day(-1)) for two years in a controlled environmental chamber. Dry mass of leaves, stem and roots, leaf area and number of leaves, and unit leaf rate were affected by both previous-year and current-year PPFD. Number of shoots and length of the main shoot were affected by previous-year PPFD but not by current-year PPFD. Number of leaves per shoot did not change with PPFD, whereas leaf dry mass/leaf area ratio was mainly affected by current-year PPFD. During the first 10 days that newly emerged seedlings were grown at a PPFD of 0.7 or 14.5 mol m(-2) day(-1), transpiration rate per unit leaf area declined. Thereafter, transpiration increased to a constant new rate. Transpiration rate per seedling was closely related to leaf area but the relationship changed with time. In two-year-old seedlings grown at various PPFD combinations of 0.7, 7.3 and 14.5 mol m(-2) day(-1) during Years 1 and 2, leaf area and transpiration rate per seedling were closely correlated at Weeks 7 and 11 after bud burst. Weak correlations were found between root dry mass and transpiration rate per seedling. During Year 2, transpiration rate per leaf area was higher at a particular PPFD in seedlings grown at a previous-year PPFD of 0.7 mol m(-2) day(-1) than in seedlings grown at a previous-year PPFD of 14.5 mol m(-2) day(-1). After transfer of two-year-old seedlings at the end of the experiment to a new PPFD (7.3 or 14.5 mol m(-2) day(-1)) for one day, transpiration rates per leaf area, measured at the new PPFD, were correlated with leaf area and root dry mass, irrespective of former PPFD treatment.     

Boundary layer conductance,leaf temperature and transpiration of Abies amabilis branches

We used three methods to measure boundary layer conductance to heat transfer (g(bH)) and water vapor transfer (g(bV)) in foliated branches of Abies amabilis Dougl. ex J. Forbes, a subalpine forest tree that produces clumped shoot morphology on sun-formed branches. Boundary layer conductances estimated in the field from energy balance measurements increased linearly from approximately 10 mm s(-1) at low wind speeds (< 0.1 m s(-1)) to over 150 mm s(-1) at wind speeds of 2.0 m s(-1). Boundary layer conductances measured on shoot models in a wind tunnel were consistently higher than field measurements. The difference between wind tunnel values and field measurements was attributable to variation in path length between the two experimental environments. Boundary layer conductance estimated by subtracting stomatal resistance (r(sV)) measured with a porometer from the total branch vapor phase resistance were unusually small. Sensitivity analysis demonstrated that this method is not suitable for coniferous foliage or when stomatal conductance (g(sV)) is small compared with g(bV). Analysis of the relative magnitudes of g(sV) and g(bV) revealed that, under most conditions, A. amabilis branches are well coupled (i.e., g(sV) is the dominant controller of transpiration). The boundary layer conductance to heat transfer is small enough that leaf temperature can become substantially higher than air temperature when radiation is high and wind speed is low. Over a two-month period, the maximum difference between leaf and air temperatures exceeded 6 degrees C. Leaf temperature exceeded air temperature by more than 2 degrees C on 10% of the daylight hours during this period. Consideration of both the photosynthetic temperature response of A. amabilis foliage as well as the summer air temperature conditions in its habitat suggests that these elevated leaf temperatures do not have a significant impact on carbon gain during the growing season.     

毛乌素沙地樟子松蒸腾变化规律及其与微气象因子的关系

本研究采用由热扩散植物液流技术测算得到的时间步长10 min的樟子松蒸腾速率数据,结合同步观测得到的冠层微气象要素值,分析了毛乌素沙区20年生樟子松主要生长季节蒸腾耗水规律及其冠层微气象的关系.结果表明:(1)樟子松蒸腾速率具有明显的时间变化特征.多云天气日,蒸腾速率日内变化总体呈多峰曲线趋势,单株蒸腾速率(Tr)在4-9月各月白天(6:00-19:00)的平均值为0.36～0.85 L·h-1;晴天日,除9月蒸腾速率日内变化呈多峰曲线趋势外,其余各月总体趋势呈单峰曲线,9月时Tr在10:00左右、13:00左右、15:00左右出现峰值,在14:00左右出现谷值.4-8月各月日内Tr在10:00左右出现峰值.4-9月各月Tr白天平均值为0.37～0.83 L·h-1;阴天天气日,蒸腾速率日内变化总体呈单峰曲线趋势,日内Tr最大值出现在10:00左右.4-9月各月Tr白天(6:00-19:00)平均值为0.29～0.63 L·h-1.在日际变化或季节变化方面,从4月份起,樟子松蒸腾耗水量逐渐增加,月耗水量在7月达到最高值,此后有所减小.4-9月总耗水量为1 143.7 mm,日平均为6.25 mm,7月份月耗水总量相对最大.4、5、6、7、8及9月耗水量分别占主要生长季节总量的10.76%、13.62%、14.05%、24.56%、19.47%、17.52%.(2)主要生长期内,Tr与冠层太阳总辐射(Ra),空气温度(Ta)、湿度(RH),风速(V)等气象要素有很好的复相关性,并通过显著性检验(a=0.01),且各月内影响樟子松蒸腾的最主要气象因子都是Ra.     

滇东南岩溶山区川滇桤木生长适应性初步研究

在砚山铳卡不同立地条件下栽培试验的初步结果表明川滇桤木在滇东南岩溶山区的石山和土山、石灰土和山地红壤上生长都比较好,表现出对不同立地条件较强的适应能力,其生长快慢与立地条件的好坏密切相关.川滇桤木的树高、地径、冠幅、叶面积、叶长、叶宽、单叶鲜重、干鲜重、枝叶鲜重和生物量等10个生长性状具有较高的一致性.川滇桤木具有育苗周期短、生长迅速、适应性强的特点,是岩溶山区营造生态防护和水源涵养林的一个优良树种,2年生平均树高为1.7m、地径为2.58cm、冠幅为0.85cm,树高最大达5.1m、地径最大达7.3cm.     

Regulation of transpirational water loss in Quercus suber trees in a Mediterranean-type ecosystem

Sap flux density in branches, leaf transpiration, stomatal conductance and leaf water potentials were measured in 16-year-old Quercus suber L. trees growing in a plantation in southern Portugal to understand how evergreen Mediterranean trees regulate water loss during summer drought. Leaf specific hydraulic conductance and leaf gas exchange were monitored during the progressive summer drought to establish how changes along the hydraulic pathway influence shoot responses. As soil water became limiting, leaf water potential, stomatal conductance and leaf transpiration declined significantly. Predawn leaf water potential reflected soil water potential measured at 1-m depth in the rhizospheres of most trees. The lowest predawn leaf water potential recorded during this period was -1.8 MPa. Mean maximum stomatal conductance declined from 300 to 50 mmol m(-2) s(-1), reducing transpiration from 6 to 2 mmol m(-2) s(-1). Changes in leaf gas exchange were attributed to reduced soil water availability, increased resistances along the hydraulic pathway and, hence, reduced leaf water supply. There was a strong coupling between changes in soil water content and stomatal conductance as well as between stomatal conductance and leaf specific hydraulic conductance. Despite significant seasonal differences among trees in predawn leaf water potential, stomatal conductance, leaf transpiration and leaf specific hydraulic conductance, there were no differences in midday leaf water potentials. The strong regulation of changes in leaf water potential in Q. suber both diurnally and seasonally is achieved through stomatal closure, which is sensitive to changes in both liquid and vapor phase conductance. This sensitivity allows for optimization of carbon and water resource use without compromising the root-shoot hydraulic link.     

不同氮磷钾施肥配比对海芒果苗期生长的影响

不同氮磷钾配施对半年生海芒果盆苗生长影响的试验结果表明:促进苗高和地径生长的较优施肥配比为N0.7 g.盆-1、P2O50 g.盆-1、K2O 0.7 g.盆-1,苗高达到84.60 cm,比对照提高了58%,地径达到1.42 cm,比对照增加了5%;提高海芒果苗木根、茎、叶干质量及叶片叶绿素含量的较优施肥配比分别为N0.7 g.盆-1、P2O50.7g.盆-1、K2O 0 g.盆-1,其中根干质量较对照增加了66%,茎干质量较对照增加了124%,叶干质量较对照增加了103%,叶绿素含量最高达4.08 mg.g-1,比对照增加了86%;影响海芒果苗木净光合速率的较优施肥配比为N1.4g.盆-1、P2O50.35 g.盆-1、K2O0 g.盆-1,叶片净光合速率最高为10.81μmol.m-2.s-1,较同时刻对照处理的叶片净光合速率提高了2.44μmol.m-2.s-1。     

Growth, leaf morphology, water use and tissue water relations of Eucalyptus globulus clones in response to water deficit

Changes in leaf size, specific leaf area (SLA), transpiration and tissue water relations were studied in leaves of rooted cuttings of selected clones of Eucalyptus globulus Labill. subjected to well-watered or drought conditions in a greenhouse. Significant differences between clones were found in leaf expansion and transpiration. There was a significant clone x treatment interaction on SLA. Water stress significantly reduced osmotic potential at the turgor loss point (Pi0) and at full turgor (Pi100), and significantly increased relative water content at the turgor loss point and maximum bulk elastic modulus. Differences in tissue water relations between clones were significant only in the mild drought treatment. Among clones in the drought treatments, the highest leaf expansion and the highest increase in transpiration during the experiment were measured in those clones that showed an early and large decrease in Pi0 and Pi100.     

黑榆不同无性系苗期表型性状及光合特征的差异性比较

为了解黑榆不同无性系的遗传变异情况,以河北省深州市栽培的15个黑榆无性系为材料,对黑榆不同无性系的生长、叶片形态和光合生理指标进行对比分析,结果表明:15个黑榆无性系间苗期生长性状及光合生理等性状指标差异显著,在15个黑榆无性系中,D7的地径最大,为2.33cm;B19平均苗高最大,为2.57m;叶长、叶宽、叶面积在不同无性系间存在显著差异,单叶面积最大相差4.1倍,不同无性系间宽长比在0.58~1.21之间变化,说明黑榆不同无性系间在叶片形态上存在着广泛的遗传变异,而且差异显著。无性系B18、D9的净光合速率最高,分别为23.54μmol/(m2·s)和23.82μmol/(m2·s);无性系D2蒸腾速率最高,为11.18mmol/(m2·s),无性系D4的蒸腾速率最低,为6.71mmol/(m2·s)。结合生长性状分析不同无性系的净光合速率,发现具有较高净光合速率的无性系,并不具有较大生长量,蒸腾速率反而和较大生长量存在显著的负相关。     

基于流体仿真的椭球型树冠抗风性能研究

近年来,随着全球气候频繁变化,台风等极端灾害性天气发生频率加剧,森林正面临着潜在的巨大损害。台风产生的风压、风速、湍流强度施加于林木上,使得林木风倒频繁发生。因此,研究树木的抗风性能有着重要意义。使用计算机仿真数值模拟方法对流场在林分中的运动进行求取,主要方法如下:首先通过GAMBIT对三维树冠进行树木建模并进行网格划分,其次使用标准k-ε方程组对三维树冠的流场分布进行模拟。最后通过模拟计算得到不同叶面积指数对应的树冠周围压力场、风速、湍动能分布。结果表明:对于单株树,当树冠孔隙度从0.25变化到0.75,即叶面积指数从2.77变化到0.58时,冠内风速在树冠内的波动幅度从8.0 m/s下降到4.0m/s,树冠内压力的波动幅度从229.0 Pa下降到到143.5 Pa,湍流强度的波动幅度从6.03%降到3.40%;对于林冠来说,当孔隙度从0.25变化到0.75,即叶面积指数从2.77变化到0.58时,在林冠前后的风速差从17.67 m/s变化为15.89 m/s,压力差从180.38 Pa变化到117.38 Pa,湍流强度的变化幅度从4.0%变化到2.4%。由于树冠前后压差过大和树冠内风速差过大会导致树的结构遭到破坏,因此,越稀疏的林冠,抗风性能越好。     

Change of trunk sap flow of Ginkgo biloba L. and its response to inhibiting transpiration treatment

For this paper, GREENSPAN sap flow system was used to monitor the dynamics of trunk sap flow of Gingkgo biloba. Results indicate that sap flow velocity is significantly different among different heights, depths, and directions of the trunk. Sap flow velocity at the upper position of the trunk is higher than that of the middle and lower position, but cumulative flux is not significantly different among the upper, middle and lower sections. Sap flow velocity at 10 mm reached the most and that at 20 mm the least. However, sap flow velocity at 5 mm and 15 mm was similar and was second among the four depths. Results also showed that sap flow velocity of the south was the highest, and that of the west was next. An Automatic Weather Station of HOBO was synchronously applied to measure these meteorological parameters, and the relationship between these parameters and the changes of trunk sap flow velocity were analyzed. We found that the change of sap flow velocity was a single-crest curve on clear days and multi-crest curve on cloudy and rainy days. In addition, it is also revealed that by stepwise regression analyses photosynthetical active radiation (PAR), temperature and wind speed are the main environmental factors affecting sap flow velocity. The efficient methods of reducing water transpiration of trees, including leaf pruning, overshadowing and antitranspirant spraying, were found by investigating the effects on inhibiting transpiration, which indicated that spraying of antitranspirants, leaf pruning and overshadowing could significantly reduce transpiration but the effects of leaf pruning and overshadowing were far better than that of antitranspirant spraying. Translated from Scientia Silvae Sinicae, 2006, 42(5): 22–28 [译自: 林业科学]