Allelopathic effect of larch leaching on ash growth in mixed forest

lntroductionConcerningthemechanismoftheinteractionbe-tWeentreespeciesinthelarch(LafisgmelinI)-ash(PraxiPusmandShuFbe)mixedforest,wehavestudiedtheaIIelopathiceff6ctsoftheIarchvolatilematter,litterandrootsecretion.onthegroWthofash.TheobtainedresultsshowedclearIythatthelarchvoIatiIematt6rplayedaninhibitivepart,andboththeIarchIitt6randrootsecretionpIayedanobviousfystimuIatingpaFtontheashgroWth(Wu2oooa,2ooob,2oooc).Thispapermakesastudyofanotherallelo-pathicway(Ieaching)betWeenlarchandash.T…     

水曲柳落叶松混交林中细根空间分布

采用根钻取样方法对年生水曲柳落叶松混交林中细根空间分布状况进行了研究。结果表明,水曲柳落叶松地下生物量的空间分配差异显著。在林分水平上,水曲柳的根生物量密度高于落叶松(分别为4442.3和2234.9g/m3)。两树种在相邻区域中分配的细根生物量较高,表明种间根系竞争较弱。落叶松行间的水曲柳细根生物量密度和根长密度均高于水曲柳行间的落叶松细根,表明水曲柳地下部分具有较强能力。根系的空间分布有利于混交林中水曲柳的生长。图1表4参19。     

THE CHARACTERS AND EFFECTS OF AVAILABLE PHOSPHORUS IN DAHURIAN LARCH-MANCHURICA ASH MIXED SEEDLING STAND

Dahurianlarch(Larixgmelinii)isamaintreesPeciesinartificialstandsandManchuriaash(Fnainusma:dehurica)isavaluabIehardwoodsPeciesinti1eforestareaofnortheastChina.SomestUdiesrevealedthatthemixedstandbythetwospecieshadpositivemixedeffectSandnutritionrelationshipwasoneofthemaincausesforthepositiveeffects.lnsomeresearches,itwasfoundthatinline-belttwoflarch-ashmixedstand,theconcentra-tionofavailablephosphorusofsoilinlarchbeltwas2ntimesoftl1atinashbelt.Itisdeducedthatinsuchmixedstandtheashcanabsorbmo…     

Spacial Patterns of Fine Root Abundance in Mixed Larch-Ash Plantation

InterspecificdiffernceIntr0ducti0nFornutrientandwaterseeking,tinerootsrepresentafuncti0nallyimportantpartofthebiomassoftbresttrees.lnforeststands,wherefinero0tsaredenselvpackedinsurfaces0iI,strongcompetitionfornutrientsandwatermaybeexpectedam0ngrootIetsan…     

Growth effect of Manchurian ash in mixed stands

lntroductionThepIantingofFraxiusm8ndShurfoabeganatShangzhi,Kedong,YianandFujincountiesofHei-longjiangProvincein196o'.Ash(hainusmand-shurica)andlarch(LarisgmehnI),AshandKoreanpine(PinuskoraiensiS)mixedstandwereremainednow,whichwereartificial,orformedbyplantingAshatterpIantingpureconiferousforest,orinducedbyestablishingeffectareainnaturalashforest.TherearemanyreferencesonthegrowthofashmixedstandinChina.Butinthepast,thestudyoftherela-tionshipbetWeentheincreasinggrowthofmixedstandwithdiffe…     

落叶松水曲柳混交林中根际土壤交换性阳离子含量的比较

通过对落叶松水曲柳混交林中根际土壤交换性阳离子的比较,得到了落叶松水曲柳混交林根际土壤交换性阳离子的变化趋势为:除钠外,落叶松的各项交换性阳离子含量均大于水曲柳,钠与钾、钙、镁存在拮抗作用,营造落叶松混交林有利于促进落叶松的生长。     

GROWTH EFFECT OF DAHURIAN LARCH-MANCHURIAN ASH MIXED FORESTS

STUDYAREAANDareTH0DThestUdyareawasatthecompatheentllofXinkenIllWorkingUnitinchoershanExPenmentalForestFann,NortheastF0restryUniversity.Dunngthespnngofl967,Dahu-nanlarchwasplantedintheleftlandofsecon-daryf0rest.Beforeorafterplanhng,mal1yMancl1tlrial1ash,e1l11withwhitebarkandsolneotherbroad-leavedtLreesinvadedandgrewwell.NowManchunanashandDahu-nanlarchn1ixedforestshavebeenf0n11ed,inwhichManchurianashisdolninant.lnl984,2Pen1lanentplotsweresetupwiththeslzeof0.O6hnl',facil1gsoutheast,…     

Effects of intercropping systems of trees with soybean on soil physicochemical properties in juvenile plantations

The intercropping system of tree with soybean in juvenile plantations, as a short-term practice, was applied at Lao Shan Experimental Station in Mao’er Shan Forest of Northeast Forestry University, Harbin, China. The larch (Larix gmelinii)/soybean (Glycine max.) and ash (Fraxinus mandshurica) intercropping systems were studied in the field to assess the effects of the intercropping on soil physicochemical properties. The results showed that soil physical properties were improved after soybean intercropping with larch and ash in one growing season. The soil bulk density in larch/soybean and ash/soybean systems was 1.112 g·cm⁻³ and 1.058 g·cm⁻³, respectively, which was lower than that in the pure larch or ash plantation without intercropping. The total soil porosity also increased after intercropping. The organic matter amount in larch/soybean system was 1.77 times higher than that in the pure larch plantation, and it was 1.09 times higher in ash/soybean system than that in the pure ash plantation. Contents of total nitrogen and hydrolyzable nitrogen in larch/soybean system were 4.2% and 53.0% higher than those in the pure larch stand. Total nitrogen and hydrolyzable nitrogen contents in ash/soybean system were 75.5% and 3.3% higher than those in the pure ash plantation. Total phosphorus content decreased after intercropping, while change of available phosphorus showed an increasing trend. Total potassium and available potassium contents in the larch/soybean system were 0.6% and 17.5% higher than those in the pure larch stand. Total potassium and available potassium contents in the ash/soybean system were 56.4% and 21.8% higher than those in the pure ash plantation. Biography: FAN A-nan (1972–), female, Ph. Doctor in Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016, P. R. China.     

Effect of nitrogen fertilizer, root branch order and temperature on respiration and tissue N concentration of fine roots in Larix gmelinii and Fraxinus mandshurica

Root respiration is closely related to root morphology, yet it is unclear precisely how to distinguish respiration-related root physiological functions within the branching fine root system. Root respiration and tissue N concentration were examined for different N fertilization treatments, sampling dates, branch orders and temperatures of larch (Larix gmelinii L.) and ash (Fraxinus mandshurica L.) using the excised roots method. The results showed that N fertilization enhanced both root respiration and tissue N concentration for all five branch orders. The greatest increases in average root respiration for N fertilization treatment were 13.30% in larch and 18.25% in ash at 6°C. However, N fertilization did not change the seasonal dynamics of root respiration. Both root respiration and root tissue N concentration decreased with increase in root branch order. First-order (finest) roots exhibited the highest respiration rates and tissue N concentrations out of the five root branch orders examined. There was a highly significant linear relationship between fine root N concentration and root respiration rate. Root N concentration explained >60% of the variation in respiration rate at any given combination of root order and temperature. Root respiration showed a classical exponential relationship with temperature, with the Q(10) for root respiration in roots of different branching orders ranging from 1.62 to 2.20. The variation in root respiration by order illustrates that first-order roots are more metabolically active, suggesting that roots at different branch order positions have different physiological functions. The highly significant relationship between root respiration at different branch orders and root tissue N concentration suggests that root tissue N concentration may be used as a surrogate for root respiration, simplifying future research into the C dynamics of rooting systems.     

Structural features of water-soluble arabinogalactans from Norway spruce and Scots pine heartwood

 Isolated water-soluble acidic arabinogalactans from Norway spruce and Scots pine heartwood were analysed and compared to Siberian larch heartwood arabinogalactans. The carbohydrate monomer composition was determined by acid methanolysis and gas chromatography, while structural studies were performed by ¹³C NMR spectroscopy and methylation analysis. The main structural features were found to be the same in the three types of arabinogalactans. However, the structure of the arabinogalactans from spruce and pine were found slightly different from the structure of larch arabinogalactans. The amount of single unit side-chains, consisting of arabinose and glucuronic acid units, was higher in the spruce and pine arabinogalactans than in the larch arabinogalactans. The amount of glucuronic acid was higher in the spruce arabinogalactans than in the pine arabinogalactans. The pine arabinogalactans had a higher amount of side chains with more than two sugar units than the spruce arabinogalactans. Received 30 December 1999     

THE SEASONAL DYNAMICS OF NUTRIENT CONTENTS IN MANCHURIA ASH-DAHURIAN LARCH MIXED STAND

StUdiesontheundeopundsboctUfCofmanchurianash-dahurianlarchmixedstandrevealedthatseveralrowsofmanchurianashtreesnearestdahurianlarchbelthaveobviouschangesofrootSindistribution,densityandgrowthtCndenCy.Numerousrootsofmanchu-rianashgrowtowardthelarchbelt,indicatingthattherewerefavorableconditionsfOrtherootstogrowinthelarchbelt.ThedahurianlarchtrCesmusthaveimprovedtheenviron-mentinsomeaspect.STUDYSlTESStUdysitessitUatedinHeilonaiiangProv-ince,mainlyinDongxingForestFarmofKe-dongcounty,wes…     

STUDY ON RELATIONSHIPS AMONG SEEDLING QUALITY AND SURVIVAL RATE, STOCKING PERCENTAGE AND GROWTH

Seedlingqualityisoneofthemostimportantfactorsinfluencingonthesurvivalrateandstockingpercentageinafforestationespecially,thequalityofseedlingmakesgreateffectsonthegroWthofdiameterandheightdirectlyincultivatinghighyieldandfastgrowthplantation.korqanpine,mongolianscotspine,dahurianlarch,koreanspruce,manchurianash,anurcorktreeandanurlindenaremainbroadleafandconiferousspeciesforwoodinNortheastofChina.Thisisbecausethatthesespeciesnotonlyhavegoodtimberqualityandfastgrowth,butalsohavehighereconomicva…     

落叶松水曲柳纯林与混交林根际土壤中养分浓度的变化

在落叶松水曲柳纯林与混交林中,采集林地土和根际土,测定了氮、磷、钾浓度,目的是探讨养分条件变化在混交林增产上的作用。结果表明:混交林林地土全氮浓度和水解氮浓度与水曲柳纯林相近,但要高于落叶松纯林。水曲柳在混交林中根际土全氮和水解氮浓度与纯林中的相近,而落叶松在混交林中根际土水解氮浓度明显高于纯林中的。混交林林地土全磷和全钾浓度与两个树种的纯林相差不大。混交林林地土有效磷、有效钾浓度均高于水曲柳纯林,而且水曲柳在混交林中根际土的有效磷和有效钾浓度与纯林中的相比明显增加,分别高出44.1%~79.6%和13.5%~25.6%。这说明水曲柳在混交林中磷和钾的利用状况得到了改善。表2参15。     

STUDY ON ECOLOGY OF FRAXINUS MANDSHURICA

STUDYONECoLoGYOFF~usmandshuricaAsll(FnainIlsmandrklIricaRupr.)isoneofthevaluablctrc9spccicsinnortheastofChina,attributcdto3rdprotcctedclassorvul-nerablesPCciesbyChinescgovernmentnot`.Sincel97o's,thcrchavcbccnsomercPOrtsaboutthistrecsPCcicsonsiIviculturc.Onabovebasis,thispaPercxPoundsmorewhatwerccentlyhavestUdiedincludingsPeCiesdistfibution,phenologyandphotOq'nthcsis,natUraIregencration,preductiviIyandcffCCtSofmixedstandsofash,assystcmaticalsum-marytoprovidcascicncebasisforthcde…     

引进木霉菌株T43对立枯病的抑制效果及对苗木的促生作用

把从以色列引进、室内抑菌试验显示对苗木立枯病菌(立枯丝核菌Rhizoctonia solani、腐霉Pythium sp.和腐皮镰刀菌Fusarium oxysporum)具有显著抑制效果的绿木霉Trichoderma virens菌株T43制成不同浓度菌剂,对落叶松Larix sp.和红松Pinus koraiensis 1年生苗木进行室外灌根处理,30 d后测定苗木生长及病害发生情况。结果表明:引进的绿木霉T43菌剂在显著控制落叶松和红松立枯病发生的同时,还显著提高苗木的生长、土壤微生物种群数量及土壤酶活性,该菌株液体菌剂适合落叶松苗木,孢子悬浮液适合红松苗木。     

Spring tree phenology in the Alps: effects of air temperature, altitude and local topography

A participatory network was set up to study tree phenology in the Western Alps. We used data collected in 2006 and 2007 on birch, ash, hazel, spruce and larch to assess how local air temperature, altitude and other topographic variables influenced dates of budburst and leaf unfolding. Altitude was, as expected, a main predictor variable of budburst and leafing dates with delays ranging from 2.4 to 3.4 days per 100 m. Ash was the only species with strong evidence of a year difference in the altitudinal gradient with the warm year (2007) characterized by a weaker altitudinal gradient. We found a latitudinal gradient in the appearance of budburst for one coniferous species (larch) and curvature affected leafing in ash. Thermal sum (sum of Degree-Days above 0 °C) was increasing with altitude for budburst (birch, ash and larch) and leafing (birch and ash). Understanding of altitude and topography effects in addition to temperature in phenological models should improve projections of future changes in mountain regions.     

Photosynthetic Characteristics of Ash and Larch in Mixture and Pure stands

IntroductionDuringthepasttwodecades,studieshaverevealedthatgrowingash(Fnainusmandshurica)andlarch(LarlksPP.)togetherinaproperwaycanincreasetheproduc-tivityQfthestandsI"'}'-'].Theyieldimprovementmechanismsattributetotwoaspects,i.e.,theabovegroundandundergr…     

Study on ecology ofFraxinus mandshurica

The reference and recent working results about ecology of ash (Fraxinus mandshurica) were reviewed, which including: distribution range, suitable site, phonology, growth, photosynthesis, productivity, natural regeneration effect and mixture effect. Synthesizing above, it was suggest that the ecological characters of ash such as distribution range, limited factors, growth site etc., as well as its biology characters, features in forest, should be considered as an important basis to develop this species by different regeneration ways such as natural regeneration, artificial regeneration and natural regeneration by man-help. And experiment in artificial regeneration showed that the mixture of ash with larch has benefit to being free from or alleviating frost injury and enhancing growth     

落叶松胶合板基础性能的研究

本文通过落叶松胶合板与其它树种胶合板在耐老化、耐腐和耐水等方面的对比试验,分析其特性.试验结果表明,落叶松胶合板比其它树种(椴、桦、杨、水曲柳)胶合板的耐老化性、耐腐性和耐水性均好,并有较高的强度.     

人工混交林不同混交方式的生长动态

对辽东山区人工混交林的生长动态进行了调查分析，结果表明，红松块状混交林型的材积生长量是红松纯林的109％-124％，落叶松块状混交林型的材积生长量是落叶松纯林的108％-151％，各混交林型中的红松、落叶松乔木层生物量比红松、落叶松纯林高3．1％-28．6％和2．8％-16％。在块状、带状混交林中的红松、落叶松，其干、枝、叶、根的生物量绝大部分都高于各自的纯林，混交林的根系分布面积比纯林提高23％。