诱导改造对大兴安岭低质林土壤理化性质的影响

2009年对大兴安岭地区的阔叶混交次生林及白桦萌生低质林进行不同带宽皆伐,将每条皆伐带分为3段,分别种植西伯利亚红松、落叶松和樟子松,2011年8月测定林分的土壤理化指标。结果表明:不同方式改造后土壤密度均不同程度地降低,而土壤毛管持水量、毛管孔隙度均不同程度地升高;与对照样地相比,阔叶混交次生林不同诱导改造后土壤全氮含量均升高(落叶松林升高98.26%,西伯利亚红松林升高72.70%,樟子松林升高44.91%),除落叶松林土壤全磷含量3.35g·kg-1保持不变外,西伯利亚红松林和樟子松林全磷含量均降低;与对照样地相比,白桦萌生低质林不同诱导改造后土壤全磷、全氮含量均有所降低,全磷含量降低程度表现为西伯利亚红松林降低38.90%、落叶松林降低33.15%、樟子松林降低11.78%,全氮含量降低程度表现为西伯利亚红松林降低36.02%、落叶松林降低36.75%、樟子松林降低37.68%;综合分析所有改造林,土壤有机质含量与全氮、全钾含量显著正相关(P﹤0.05);不同带宽西伯利亚红松林的土壤pH值、有机质含量、全氮含量及全钾含量变异系数最大,说明带宽对西伯利亚红松诱导林土壤理化性质有显著影响。     

Decay threshold of acetylated rattan (Calamus manan) against soft rot

We investigated the resistance of acetylated rattan against soft rot and other soil inhabiting micro-organisms in comparison with wood of beech and Scots pine. Calamus manan of 10 and 13 years old under rubber tree canopy was acetylated to different levels by reaction times (0.25 to 30 hours) and was tested for soft rot decay for 32 weeks. Acetylated rattan at decay protection thresholds of 15.4% and 16.2% weight gain (WG) were fully protected, as shown by both weight loss and strength loss criteria. The static bending properties of untreated rattan decayed by soft rot were significantly lower than for acetylated rattan.     

Study on community structure and self-sustaining mechanism of broad-leaved/Korean pine forests in northeast China

INTRODUCTloNbePthemp`vkoItw)isanli11pe1tclhabepeicinnoed1castO1ina.Thcspeic~rminn1bo\vithInanyhar~~,inbotScalledndbroadileated/KOrCantwthisisthecham~honin~toinla.bendboare~lycalledKrsPincbofOrdnd.ThebohavcboexPloitalforwtahalf~,withiISareabeing~boIhan5oto5~inthiswil,].TO-tw-oroldgrowthbonaatonlyiminfewedwr.beusePaSttimeduetOwithe~mCChanisl1isofthenabotwpePlanboonsofKrsptheunmaseeqclear~ofhsenahahenrstaredanopmcaedtyforndnd'l,.ndmamAnboontisetOPofnd3l.Hot`toodthehighqtaltyorboPli…     

Legacies from natural forest dynamics: Different effects of forest management on wood-inhabiting fungi in pine and spruce forests

The species composition of wood-inhabiting fungi (polypores and corticoids) was investigated on 1138 spruce logs and 992 pine logs in 90 managed and 34 natural or near-natural spruce and pine forests in SE Norway.Altogether, the study included 290 species of wood-inhabiting fungi. Comparisons of logs with similar properties (standardized tree species, decay class, dimension class) in natural and managed forests showed a significant reduction in species number per log in managed spruce forests, but not in managed pine forests. The species number per log in managed spruce forests was 10-55% lower than on logs from natural spruce forests. The reduction was strongest on logs of large dimensions. A comparison of 200-400 spruce logs from natural and managed forests showed a 25% reduction in species richness corresponding to a conservative loss of ca. 40 species on a regional scale.A closer inspection revealed that species confined to medium and very decayed spruce logs were disfavored in managed forests, whereas species on early decay classes and decay generalists were unaffected. Similarly, species preferring large spruce logs were disfavored in managed forests. Forest management had strongest impact on low-frequent species in the spruce forests (more than 50% reduction), whereas common species were modestly affected. Corticoid fungi were more adversely affected than polypore fungi.These results indicate that wood-decaying fungi in pine forests are more adapted to forest disturbances than spruce-associated species. Management measures securing a continuous supply of dead wood are more important in spruce forests than in pine forests.     

A succession and silviculture model for the broad-leaved Korean pine forests of Changbai Mountain Area

IntroductionGaPSinforestSwereoftenfomledduetobigtreesfalldown.Regenerationandgrowtl1inthegapsincreasebe-causeofIheAnprovementoflightcondition-Thegapwillbefilledwithnewregeneratedtrees.Wattnamedtl1isforesIdynamicsastheforestgrowtllcycle.SinceD.Bot-kindevelopedthefirstGapmo`Iel(JANOWAnlodel)basedontheforestgrowthcycletheory,dleresearchongapmodelbecameoneofthemostactivedirectio11slilecologybecauseofJANoWAnlodeI'ssuccess.H.Sl1ug-artandhisstUdentSmadegreatc()ntributio11stogapmodeI'sdeve…     

Comparison of <Emphasis Type="Italic">Pinus taeda</Emphasis> L. whole-tree wood property calibrations using diffuse reflectance near infrared spectra obtained using a variety of sampling options

A necessary objective for tree-breeding programs, with a focus on wood quality, is the measurement of wood properties on a whole-tree basis, however, the time and cost involved limits the numbers of trees sampled. Near infrared (NIR) spectroscopy provides an alternative and recently, it has been demonstrated that calibrations based on milled increment cores and whole-tree data can provide good estimates of whole-tree properties. Several options exist for sampling standing trees and the aim of this study was to compare wood property calibrations based on NIR spectra collected from samples obtained using different sampling methods. Calibrations for whole-tree lignin and basic specific gravity based on NIR spectra from whole-tree chips (milled or intact) had the strongest statistics, calibrations based on NIR spectra from milled increment cores were similar. Other options for sampling the tree (drill shavings, etc.) gave errors that were too large for practical applications. If an increment core is going to be used to estimate whole-tree properties, it is recommended that it be dried and milled prior to analysis.     

A high-throughput X-ray-based method for measurements of relative wood density from unprepared increment cores from Picea abies

We have described a high-throughput method for ring width and relative wood density analysis of unprepared increment cores based on conventional computer tomography scanners (CT scanners) used in health care. The method was developed for analysis of 5-mm increment cores collected in forest genetic and tree breeding trials. For these studies, the relative differences between individuals are more important than the exact value. The method is highly efficient in terms of quantitative data collection from large number of samples. There are, however, limitations in terms of resolution and accuracy on very small volumes of wood that must be considered when using the method to measure individual growth rings or increment cores thinner than 5 mm. However, in studies comprising large number of samples, the use of cost-efficient CT scanning on the major part of the material, combined with more laborious high-resolution scanning on sub-samples can be a good combination for efficient determination of radial variation in growth rate and wood density.     

基于“近自然林业”的红松林主要树种重要值的研究

以“近自然林业”为指导思想,对凉水自然保护区不同类型红松林主要树种的重要值进行了研究。结果表明：红松在天然林内并不占据优势地位;红松人工纯林内红松的重要值都很大,都大于同林分内的阔叶树主要树种的重要值之和;林隙透光抚育林内红松的重要值为107．98％,而其他几个阔叶树种色木、白桦、椴树和杨树的重要值相加为121．69％,主要树种中针叶树种和阔叶树种的比值接近1∶1,这种重要值的比率使整个林分的针阔比处于一种平衡的状态。     

STUDY ON THE SITE OF KOREAN PINE PLANTATION ON THE MAOER MOUNTAIN

1NTRODUCT1oNMaoerMountainliesintheeasternpartofnortheastChinamountainareawithinthenaturalgeographicaldistributionrangeofavaluabletimberspeciesofKoreanpine(PinusKoraiensis).Foraboatmorethanlooyears,cuttinganddestroyingcontinued;f9wnaturalprimaryKoreanpineforestsleft.AlargeareaofKoreanpineplantations,nevertheless,has'grownupastimegoing.Itisapressingproblemforushowtocultivatethemwell,andtorecoveranddevelopthemraPidlyinourforestproductionandscientificresearch.FortheKoreanpinetree,peopledid…     

Effects of thinning and canopy type on growth dynamics of Pinus sylvestris: inter-annual variations and intra-annual interactions with microclimate

We assessed the effects of thinning (0, 20 and 30 % extraction of basal area) and canopy type (pine–beech vs. pine plots, beech accounting for 12 % of total basal area) on radial growth of dominant and codominant Scots pine at inter-annual scale and on microclimatic conditions, radial growth and xylogenesis 9 years after thinning at intra-annual scale. Thinning weakly affected pine growth, which was enhanced 3 years after harvesting. Over time, a gradual reduction in pine growth in mixed canopy relative to pure canopy occurred only in unthinned plots apparently due to beech expansion. Indeed, 9 years after thinning, a higher seasonal radial increment and a greater number of tracheids were produced under pine canopy in the unthinned plots, whereas no differences between canopy types were observed in the thinned plots. Radial increment and tracheid production were mainly affected by tree water status (air and soil humidity, throughfall). The differences of tree water status caused by treatments, and plausibly disparities in tree size and tree-to-tree competition, were the main drivers explaining the patterns observed for radial increment and xylogenesis. Our results suggest that the negative effects of beech competition on Scots pine growth in similar mixed forest may be controlled to some extent by thinning.     

辽东山区不同森林类型土壤改良效益分析

辽宁东部山区是辽宁省浑河、太子河等主要河流的发源地和集水区,为辽宁省中南部工农业生产和人民生活用水提供保障。通过对该地区柞树林、杂木林、落叶松林、红松林、油松林等5种主要森林类型的林下枯落物层积累、土壤的物理化学性质等方面进行比较分析,研究结果表明:阔叶林在土壤改良、涵养水源方面较针叶林好,因此,在辽东山区营林时应多营建阔叶林或针阔混交林。     

Over-mature beech trees (Fagus orientalis Lipsky) and close-to-nature forestry in northern Iran

Oriental Beech is the most important commercial tree species in northern Iran. In recent years wood production companies interested in felling large beech trees for profit have challenged advocates of close-to-nature silviculture who favor conservation. Our study objective was to assess the economic value of over-mature beech trees by relating tree diameter (DBH) to amount of decay. Based on the location of onset of decay, we categorized three types of decay as stump, stem, and crown decay. Trees of greater diameter (age) typically showed greater decay in the stem. Percent of decayed volume, diameter of decayed tissue, and length of decay in tree stems varied between 0.5%?64.3%, 15 cm?75 cm, and 2.0?19.5 m, respectively. With increasing trunk diameter, the proportion of truck decay increased. Red heart and dark red heart constituted 25% and 14.3% of sampled trees, respectively. However, we found no correlation between intensity of stem decay and morphological characteristics of trees. Seedlings were not abundant around the bases of over-mature trees, suggesting that the trees did not contribute to regeneration of the stand. Beech trees of diameter >1 m do not provide valuable round wood for industries and cause to raise wood production costs. We recommend that these trees >1 m DBH should be retained in forest stands because of their low commercial value but high ecological and conservational values such as maintaining biodiversity in forest ecosys-tems.     

Utility pole decay

Summary Air-dried and kiln-dried southern pine sticks, representing a number of different trees, were individually inoculated with one of the nine basidiomycetes most often associated with southern pine utility pole decay. Where available, four different strains of each fungus were used to prepare decayed wood for testing. The partially decayed sticks were then tested with 53 chemicals, or combinations of chemicals (indicators), to determine their efficacy in detection of decay through color changes wrought in the affected wood. Nine indicators, or combination of indicators, showed promise in detection of some of the included decay. Of these, three were subjected to further testing on decayed lodgepole and ponderosa pine woods. The three—butter yellow+methylene blue followed by bromcresol green+methyl orange; chrome azural-S; and methyl orange+indigo carmine—were considered suitable for use in detection of internal decay in pine poles.This work was supported, in part, by the Naval Facilities Engineering Command, U.S. Navy. Trade names are for the readers' convenience only, and are not to be construed as recommendations by the U.S. Department of Agriculture.     

山西太岳山典型森林群落土壤有机质及氮素研究

分析了太岳山7种典型森林群落土壤有机质和氮素的基本状况,结果表明:不同林型,土壤腐殖质层和淀积层有机质含量均是油松辽东栎混交林最高,分别为4.908g/kg和3.528g/kg;土壤腐殖质层有机质含量油松林最低,为3.959g/kg,淀积层有机质含量山杨林最低,为1.779g/kg;土壤腐殖质层全氮含量,白桦林最高,为0.368%,辽东栎林最低,为0.176%。;土壤腐殖质层速效氮含量华北落叶松林最高,为292.191mg/kg,油松林最低,为167.725mg/kg;土壤淀积层全氮含量油松林最高,为0.277%,油松辽东栎混交林最低,为0.094%;土壤淀积层速效氮含量山杨林最高为200.183mg/kg,油松辽东栎混交林最低,为49.151mg/kg;土壤有机质、全氮及速效氮含量均是上层土壤高于下层。腐殖质层和淀积层土壤有机质含量在各林型间差异均不显著(P>0.05),而全氮和速效氮含量在各林型间的差异均达到极显著水平(P<0.01)。     

Sorption of acetylated pine wood decayed by brown rot, white rot and soft rot: different fungi—different behaviours

Acetylated wood was exposed to decay by brown, white and soft rot in order to address the sorption behaviour of decayed wood. The sorption isotherms were analysed using the Hailwood–Horrobin model. It was found that the different types of decay exhibit different sorption properties. Brown rot decayed wood exhibits significantly lower hygroscopicity in both total, monomolecular and polymolecular sorption. Soft rot decayed wood followed the same pattern as the brown rot decayed wood; however, the reduction in hygroscopicity was not significant. White rot decayed wood showed a different behaviour, with increased hygroscopicity in total and polymolecular sorption and decreased hygroscopicity in monomolecular sorption.     

Seasonal dynamics of wood formation: a comparison between pinning,microcoring and dendrometer measurements

Three different methods were evaluated for analysing wood formation of Norway spruce [Picea abies (L.) Karst.] and Scots pine (Pinus sylvestris L.) in Finland. During two growing seasons, wood formation dynamics were determined both by wounding the cambium with a needle followed by localisation of the wound-associated tissue modification after the growing season (pinning), and by extracting small increment cores during the growing season (microcoring). Stem radius was additionally monitored with band dendrometers. For Norway spruce, pinning and microcoring yielded similar dates for the onset of wood formation. The timing of wood production during the growing season was also similar for pinning and microcoring. For Scots pine, the onset of wood formation was recorded from microcores almost 2 weeks later than from pinning samples. In Scots pine, microcore measurements also produced somewhat later cessation dates for tracheid formation than the pinning samples. For both tree species, the total number of tracheids formed during the growing season was, however, about the same for pinning and microcoring. Dendrometer results clearly differed from those of pinning and microcoring. In particular, the dendrometers showed an increase of stem radius considerably earlier in spring, when the other methods did not detect wood formation. Thus, pinning and microcoring currently represent the most reliable techniques for detailed monitoring of wood formation.     

利用RAPD技术对牡丹江地区红松根际土壤微生物多样性的分析

土壤微生物对土壤中有机质的转换起着至关重要的作用,土壤微生物多样性的变化对地表生态系统、土壤的结构、土壤的肥力和植物的健康等有重要的影响.本文利用RAPD技术分析牡丹江地区的3个林型及其3个不同林龄共9块样地的根际微生物的多样性,得到了椴树红松林、蒙古栎红松林和云冷杉红松林3种林型内的土壤微生物多样性的变化趋势,及其微生物构成差异性.     

Tree effects on the chemical topsoil features of oak, beech and pine forests

We aimed to study tree effects on the chemical properties of forest soils. We compared soil features of three types of forest ecosystems, each with four stands (replicates): beech forests (Fagus sylvatica), oak forests (dominated by Quercus pyrenaica) and pine plantations (Pinus sylvestris). Five samples from the top 10 cm of soil were taken per stand, from which pH, organic matter content (O.M.), total nitrogen (N) and available calcium (Ca²⁺), magnesium (Mg²⁺), potassium (K⁺) and sodium (Na⁺) were determined. Litter layer depth was measured at each soil sampling point. We also measured tree density and crown diameters at each stand. Our results indicated that soil samples from the four pine plantation stands were more similar while oak and beech stands were characterised by great variability in terms of soil properties and leaf litter depth. Although the identity of the dominant tree species significantly influenced several topsoil chemical properties (increase in pH and available cations in oak forests and higher organic matter and total nitrogen in beech and pine ecosystems), there were other important factors affecting soil features that may be taken under consideration. Differences between soil properties of the three types of forest ecosystems were mainly related to the characteristics of the litter layer and less related to the tree layer structure. Finally, the establishment of pine plantations in naturally deciduous tree areas made the topsoil features more homogeneous.     

天然红松阔叶林林木分布格局研究的最小样本量

利用角尺度法分析了天然红松阔叶林林木个体的空间分布格局,采用数学模型对抽样点数与对应林木空间分布格局吻合率的关系进行拟合,将拟合方程二阶导数开始趋近于0的点对应的样点数确定为林木空间分布格局抽样调查的最小样本量,并利用9块模拟样地及2块厄瓜多尔天然林样地的资料进行分析,进一步求证最小样本量的合理性.结果表明,天然红松阔叶林空间分布格局调查的最小样本量为49.     

Detection of incipient decay in tree stems with sonic tomography after wounding and fungal inoculation

Picus^® acoustic tomography was used to map incipient stages of fungal decay in the sapwood of standing Douglas fir, beech, oak, and sycamore trees 2, 16, and 27 months after wounding and artificial inoculation with brown-, soft-, and white-rot decay fungi. Some wood properties were additionally measured before (velocity of sound) and after (moisture content, weight loss, and density of sound, discoloured and/or decayed wood) tree felling (28 months). With the exception of Trametes versicolor in sycamore, wood decay was not evident from the tomograms in any host-fungus combination. In comparison to measurements after two months, the device recorded a reduction in sound velocity in some host-fungus combinations after 16 and 27 months. In beech, there was a significant reduction in sound velocity after inoculation with Ganoderma applanatum, Kretzschmaria deusta, and Trametes versicolor. Similarly, a reduction in sound velocity was recorded in sycamore inoculated with Kretzschmaria deusta and Trametes versicolor. In all these combinations, losses in wood weight and wood density were also found. Results showed that the detection of incipient fungal decay at the periphery of tree stems needs to be improved such that tomograms of the Picus^® acoustic tomograph are capable of identifying decay progressing from the sapwood inwards.