’97林业部科技成果推广项目简介(三)

黄淮海平原兰考泡桐胶合板材林优化栽培模式（1）建立了黄淮海地区兰考泡桐立地分类和立地质量评价系统。该系统分立地类型区编制了4个数量化地位指数得分表，解决了有林地和无林地立地质量的统一评价问题；提出了27个适于兰考泡桐胶合板材林培育的立地类型；构建了可用来预测备适生立地类型兰考泡桐平均胸径和林积生长过程的生长模型。（2）对兰考泡桐成林的林分结构首次进行了全面、系统的研究，建立了兰考泡桐林分的直径结构、材种结构、平均胸径、干曲线和各材种出村量预估模型。得出了不同立地指数级林地培育泡桐胶合板材林的最适密度…     

中龄兰考泡桐胶合板材林营养补给效应的研究

中龄兰考泡桐胶合板材林营养补给效应的研究＊王保平李宗然李芳东周海江周道顺关键词兰考泡桐胶合板材林营养补给合理营养补给是泡桐胶合板材林定向培育集约栽培的一项重要措施，以前对幼龄泡桐进行营养补给的研究较多［１，２］，但缺乏对中龄泡桐林营养补给的研究，尤其...     

兰考泡桐林分结构规律研究

通过对１１７块兰考泡桐地资料的分析，发现兰考桐一接干的高度与立地和苗木质量间存在着正相关，二次接干的高度与一接干的高度存在负相关，不同立地和不同年龄林分各径阶树高变化规律可用建立的兰桐标准树高曲线表达，兰考泡桐林分的直径结构可用Ｗｅｉｂｕｌｌ密度函数或Ｌｏｇｉｓｔｉｃ生物种群模型恰当描述，但从预测的角度出发Ｌ－ＰＲＭ（Ｌｏｇｉｓｔｉｃ）较之ＰＲＭ（Ｗｅｉｂｕｌｌ）效果更好。     

兰考泡桐根材和枝桠材解剖特性和基本密度的研究

测定研究了不同直径兰考泡桐的根材和枝桠材的各种解剖因子及其基本密度，结果表明：兰考泡桐根材和枝桠材构造区别明显，不同直径的根材和枝桠材木材解剖性和基本密度均有变异，仅少数指标差异显著，根材和枝桠材相比，基本密度和木纤维含量为枝材＜根材，其余因匀为根材＞枝材。进一步分析论证表明，根材和枝桠材是刨花板的好原料；而枝材适宜于生产纤维板，但根材不合适。     

杉木人工林直径分布收获预估模型的研究

把直径密度效应模型和同龄纯林自然稀疏方程结合在一起，预估不同年龄阶段的平均直径和单位面积上立木株数。在此基础上，选择Weibull分布函数，用参数回收技术建立杉木人工林直径分布收获预估模型。该模型不仅能输出林分在各个年龄阶段的总体收获量（蓄积量和出材量），而且能输出各径阶的收获量，为经营决策者提供了详细的信息，也为编制包括材种出材量在内的收获表提供了新途径。     

兰考泡桐适生条件调查

我省1975年引种兰考泡桐.川中丘陵缺材区一个县在四旁种植数百万株.大面积育苗和造林其生长速度都比原产地快.如一年生平茬苗高达10.38米为全国之冠;造林后的直径年生长量,最优单株达8厘米.初期年直径生长量达3—5厘米,但立地条件对生长量的影响很大.本文拟重点讨论土壤条件与兰考泡桐生长的关系.     

木芯复旋是提高木材利用率的途径

我国的胶合板材最小径级规定为26cm但由于胶合板材资源的减少,原料的径级也越来越小。从本厂的情况看,椴木的平均直径由1987年的34cm降至1989年的30cm,水曲柳由40cm降至34cm。有的企业,为了生产不得不把质量较好的直径为24cm或者还要小的原木也作为胶合板材使用。致使,胶合板材利用率越来越低。我厂生产1m~34′×6′胶合板的原木消耗量1987年为2.67m~3,1989     

马尾松大径材林分密度的探讨

分析马尾松大径级用材林林分密度与生长量、材种出材量和直径分布的关系,结果表明,为获得较多的大径材,培育马尾松大径材用材林以初植密度1 200～1 800株/hm2和最终保留密度750～1 050 株/hm2为宜.探讨了马尾松大径级用材林培育技术措施,提出抓紧编制大径级用材林基地建设规划,并制定大径级用材林培育技术标准等建议.     

淮北平原砂姜黑土兰考泡桐立地分类与评价及生长模型的研究

兰考泡桐（Paulowniaelongata）是淮北平原砂姜黑土上的主要造林树种．为了提高造林质量，提高林业经营与决策的科学水平，开展了该区兰考泡桐立地类型划分、立地质量评价及生长模型的研究．通过调查该立地上兰考泡桐的生长情况．应用数量化理论筛选该类土壤影响兰考泡桐生长的主导因子，划分了9个立地类型．应用Richards函数为导向曲线，以平均优势木胸径为评价指标，导出了地位指数模型．编制了数量化地位指数得分表，实现了有林地与无林地的统一评价．根据兰考泡桐在这一地区栽培密度小的特点，建立了平均本胸径和平均本材积的单木生长模型．     

黄淮海平原兰考泡桐立地分类的研究

本文以黄淮海平原兰考泡桐为研究对象，通过分析各立地因子的分异规律，逐级找出划分立地分类单元的主导因子。在进行立地类型划分时，以样地的平均优势木胸径作为生长指标，应用数量化理论Ⅰ进行回归分析，筛选出与兰考泡桐胸径生长密切相关且直观易测的几个因子（如土壤质地、地下水位等），作为划分立地类型的主导因子，将这些因子进行组合划分出立地类型，从而建立起黄淮海平原兰考泡桐立地分类系统     

I-69杨胶合板用材林产量及生物量结构

采用 2 90块标准地调查资料 ,分析了 I- 6 9杨胶合板用材林的产量和生物量结构随立地指数和造林密度的变化规律。胶合板材产量随立地指数的增大而增大 ,且占总产量的百分比在立地指数为 14、16、18m时 ,随造林密度的增大而减小 ;当立地指数为 2 0 m和 2 2 m时 ,保持稳定在 50 %左右。磨木浆材和化学浆材产量随立地指数和密度的增大而增加。在立地指数为 14、16、18m时磨木浆材产量占总蓄积量的百分比和化学浆材产量占总蓄积的百分比均随造林密度的增大而增大 ;在立地指数为 2 0、2 2 m时则受造林密度的影响不大 ,分别保持在 30 %和 2 0 %左右。林分和单株的树干、树枝、树皮生物量组成比例均随立地指数、造林密度的变化无明显的差异。营造 I- 6 9杨胶合板用材林时选择立地指数 2 0、2 2 m的地段以及用造林密度 156 (8m× 8m)、2 0 4 (7m× 7m )株·hm-2 为最佳。     

苏北京杭大运河堤杉木引种栽培研究

在苏北京杭大运河堤引种种栽培杉木研究结果表明，粗放经营林分，１９ａ时Ｈ１２．３０ｍ，Ｄ１．３１９．１ｃｍ立木积量２２４．０ｍ＾３／ｈｍ＾２，地上部分生物量达１４７．ｄ１２ｔ／ｈｍ＾２中径材５１．１％，小径材占４６．６５；集约管抚林分，１３ａ时Ｈ１１．９０ｍ，Ｄ１．３１５．１ｃｍ，立木蓄积量和地上部分生物量分别达２０４．７３ｍ＾３／ｈｍ＾３和１１１．０５ｔ／ｈｍ＾２，中小径材各占４８．４％。广西融水     

无性系和株行距对杨树人工林生长和树冠结构的影响

【目的】探索无性系、株行距及两者交互作用对杨树人工林的林木生长和树冠结构的影响。【方法】采用双因素随机试验设计,通过调查36块13年生杨树样地胸径、树高、活枝下高和冠幅等指标,以综合指数法构建3个林分综合指数(生长指数、冠形指数、干冠协调指数)。【结果】南林95杨和南林895杨的胸径、树高和生长指数显著高于南林797杨(P <0.05)。南林797杨的冠幅、树冠体积和树冠圆满度显著高于南林895杨,与南林95杨差异不显著(P> 0.05)。株行距为6 m×6 m和4.5 m×8 m的林分胸径、冠形指数和生长指数均显著高于5 m×5 m和3 m×8 m林分,不同密度林分对树高影响不显著(P> 0.05)。在相同密度条件下,正方形和长方形配置对东西和南北冠幅有显著影响,较大株行距促进树冠生长,但对胸径、树高和平均冠幅等影响不显著(P> 0.05)。无性系和株行距对冠长、活冠比、树冠表面积和干冠协调指数影响均不显著,且无性系和株行距对林木生长和树冠结构均无显著交互作用(P> 0.05)。【结论】杨树无性系对林木胸径、树高和树冠结构的影响大于株行距。综合考虑林木生长和树冠结构等两个方面,在类似的立地条件上,相比于其它无性系和配置方式,以南林95杨在种植株行距为6 m×6 m(278株/hm^2)时具有培育大胸径林木的潜力,适于培育速生、优质大径材。     

不同密度杉木林分下套种闽楠的生长分析

以福建省顺昌县杉木-闽楠复层林为研究对象,对不同保留密度杉木林下套种闽楠的林分生长进行调查分析。结果表明,随着杉木保留密度的增加,闽楠的平均胸径、树高、单株材积、冠幅、枝下高以及最大分枝粗均降低。西坑试验点内,1~6号样地(杉木保留密度为180株·hm^-2)的林下闽楠平均胸径和树高较7~8号样地(杉木保留密度为480株·hm^-2)的分别增加149.01%和88.95%;八一工区试验点内,1~2号样地(杉木保留密度为485株·hm^-2)的林下闽楠平均胸径和树高较3~4号(杉木保留密度为630株·hm^-2)、5~6号样地(杉木保留密度为825株·hm^-2)分别提高了19.75%、7.02%和40.04%、42.46%;西坑试验点内,1~6号样地,胸径超过30 cm的杉木株数占杉木总株数的88.30%,径阶分布更集中,7~8号样地,这一比例则仅为69.40%;八一工区试验地内,1~2号样地,胸径30~40 cm的杉木株数占杉木总株数的比例较3~4号、5~6号样地分别提高了70.89%和221.29%。结果表明,降低杉木保留密度(或增加间伐强度)有利于下层闽楠的生长和上层杉木大径材的培育。     

Growth and nut production of black walnut in relation to site, tree type and stand conditions in south-central United States

Black walnut (Juglans nigra) is a prime tree species for agroforestry practices in the United States providing highly prized wood and nuts for human consumption and wildlife. In 54 black walnut stands in south central United States, the site index (i.e., mean dominant height [DH], at age 25 years) ranged between 5.2 and 21.4 m, and was independent of stand density. There were no differences in height and stem diameter (DBH) growth rates between stands with improved varieties and native stock. Most stands were in a “free growth” stage because of either early age or wide spacing. Mean annual increments in DBH and height were positively related both for improved varieties and native stock. Understory competition had a substantial detrimental effect on DH. In a 26 year-old stand, trees growing within Kentucky blue grass (Poa pratensis) had a site index 5 m greater than trees growing within tall fescue (Festuca arundinacea). Predicted nut yields in 2002 varied between 0 and 1370 kg of hulled nuts per ha. Improved varieties had, in general, higher nut yields than predicted from a nut yield-DBH equation developed for individual trees. Nut yields were highly variable both within and among stands, and were related to DBH in native stock but not in improved varieties.     

Growth reduction in harvest-age,coniferous forests with residual trees in the western central Cascade Range of Oregon

To evaluate the relationship of overstory residual trees to the growth of unmanaged young-to-mature understory Douglas fir (Pseudotsuga menziesii (Mirb.) Franco) and western hemlock (Tsuga heterophylla (Raf.) Sarg.), the basal area and volume of 14 paired plots with and without residual trees were examined in the Willamette National Forest, Oregon. Residual trees were large survivors of the fires that initiated the understory between 55 and 121 yr ago. Understory stands were naturally regenerated and not managed in any way. High residual tree and understory densities were negatively associated with understory volume. The relation of density of residual trees to total understory and Douglas-fir basal areas and volumes was best described by a negative logarithmic function. The rate of decrease in total understory and Douglas-fir basal areas and volumes per individual residual tree became smaller with increasing residual-tree density. Predicted total understory volume reduction was 23% with five residual trees/ha and 47% with 50 residual trees/ha, averaging 4.6% and 0.9% per residual tree, respectively. After including the estimated volume growth of residual trees since initiation of the understory, stand volume was still 19% lower with five residual trees/ha and 41% lower with 50 residual trees/ha than in stands with no residual trees, averaging a reduction of 38% and 0.8% per residual tree, respectively. In mixed stands of Douglas fir and western hemlock, predicted Douglas-fir basal area and volume declined more rapidly than did total understory basal area and volume when residual-tree densities exceeded about 15 trees/ha. This difference was probably due to the relative shade-intolerance of Douglas fir. Predicted Douglas-fir volume reduction was 13% with five residual trees/ha and 75% with 50 residual trees/ha, averaging 2.6% and 1.5% per residual tree, respectively. The southern aspects had more than 150% the total understory basal area and volume and more than 200% the Douglas-fir volume and basal area of the northern aspects. Lower density and basal area of understory trees, particularly of dominant and codominant Douglas fir, were associated with increasing residual-tree densities. Given the same diameter at breast height (DBH), heights of Douglas fir were not related to residual trees. Regardless of understory age, understory volume was greatest in stands with the lowest understory densities. These results suggest that timber production in unthinned green-tree retention units may be reduced and may depend on the density of leave-trees. Thinning of understory trees is recommended to reduce growth loss from intraspecific competition.     

建立相似林分样木因子回归模型推算采伐木蓄积

在安化县杉木人工林相似林分内设立样地,测量样地对角线上26株林木的地径、胸径和树高,用Excel软件建立地径与胸径、胸径与树高的回归模型,再测量采伐木地径,用回归模型预测采伐木的胸径和树高,推算采伐木蓄积量。同时,采用地径一元立木材积表法测算林木蓄积量,并与采伐作业设计的二元立木材积表法测算的林木蓄积量相比较。结果表明:采用建立相似林分样木因子回归模型推算采伐木蓄积量方法接近采伐作业设计的蓄积量。     

Effect of thinning intensity on tree growth and temporal variation of seed and cone production in a Pinus koraiensis plantation

Thinning of Korean pine (Pinus koraiensis Sieb. et Zucc.) is used to facilitate timber and cone production. The present study in Northeast China investigated the effects of thinning intensity on individual tree growth, temporal variation in cone yield, and seed quality in Korean pine plantation. In 2005, five thinning intensity levels (none, extreme, heavy, moderate and light) were set in 15 permanent plots in a 32-year-old Korean pine plantation at Mengjiagang Forest Farm, Jiamusi City, Heilongjiang Province. We recorded tree growth and seed cone production from 2013 to 2016, i.e., from 8 to 11 years after thinning. Except for height growth, thinning increased tree growth (diameter at breast height and crown size) and improved cone yield. The extreme thinning treatment (to 300 trees per hectare) resulted in the largest tree diameter, tree volume, crown size and 4-year cone production per tree. The highest cone yield per tree in the mast year (2014) was observed when stands were thinned to 500 trees per hectare (heavy thinning). Although the best cone and seed quality and the largest cone and seed mass per tree were recorded in the heavily thinned stand, no significant differences were found between heavy and moderate thinning stands (750 trees per hectare). At the stand level, the moderately thinned stand had the highest basal area, stock volume and seed cone production per stand. Our results suggest that thinning to 750 trees per hectare will improve timber and cone productivity in 40-year-old P. koraiensis stands.     

11年生马尾松种子园自由授粉子代测定林的分析研究

通过对漳平五一国有林场11年生90个家系马尾松种子园自由授粉子代测定林的生长性状调查研究,在对比分析、方差分析基础上判定家系优劣,估算遗传参数与计算遗传增益。结果表明:各家系间树高、胸径、单株材积差异达极显著水平,具有较高的遗传力。11年生时入选的28个优良家系平均树高、平均胸径、平均单株材积分别为11.7 m、15.0 cm、0.0991 m3,遗传增益分别为3.3%、13.4%、31.8%;在优良家系内进行优良单株选择,入选103个单株,平均树高、平均胸径、平均单株材积分别达到12.4 m、17.7 cm、0.1440 m3。遗传增益分别达4.7%、23.9%、69.1%。可显著提高马尾松用材林的产量。