基肥对油茶幼林地径和冠幅生长的影响

为了探究基肥对油茶幼林地径、冠幅生长的影响,以油茶优良无性系长林40号新造林为试材,通过施入不同类型基肥配方进行正交施肥试验,并对2008年~2012年油茶幼林的地径、冠幅增长量与不同类型基肥及配方的关系进行方差分析。结果表明:基肥对油茶幼林地径、冠幅的生长起关键作用,复合肥和菜枯肥作基肥施入能够显著提高油茶幼林的地径和冠幅生长量,且基肥的有效时间可持续5 a;油茶幼林最佳基肥配方为钾肥0.78 kg/株+菜枯肥3.49 kg/株+磷肥1.61 kg/株+复合肥0.93 kg/株。     

Modeling individual tree height growth of Norway spruce and Scots pine from national forest inventory data in Norway

We developed individual tree height growth models for Norway spruce (Picea abies (L.) Karst.) and Scots pine (Pinus sylvestris L.) in Norway based on national forest inventory data. Potential height growth is based on existing dominant height growth models and reduced due to competition by functions developed in this study. Three spatially explicit and two spatially non-explicit competition indices were tested. Distance effects and diameter ratio effects were estimated from the data simultaneously with parameters of the potential modifier functions. Large height measurement errors in the national forest inventory data caused large residual variation of the models. However, the effects of competition on height growth were significant and plausible. The potential modifier functions show that height growth of dominant trees is largely unaffected by competition. Only at higher levels of competition, height growth is reduced as a consequence of competition. However, Scots pine also reduced height growth at very low levels of competition. Distance effects in the spatially explicit competition indices indicated that the closest neighbors are most important for height growth. However, for Scots pine also competitors at larger distance affected height growth. The five competition indices tested in this study explained similar proportions of the variation in relative height growth. Given that unbiased predictions can only be expected for the same plot size, we recommend a spatially explicit index, which describes the distance function with a negative exponential, for use in growth simulators.     

辽宁东部地区主要树种组林分平均胸径生长率模型的研究

该文采用超总体理论编制辽宁省东部地区主要树种组林分平均胸径生长率通用模型,以2005年森林资源二类调查资料为原始数据,涵盖辽宁东部7个市31个县（市、区）8个树种（组）在不同地理位置和不同立地条件的生长水平。建立4种模拟方程,通过拟合与优化及结果精度的检验选出了各树种组的平均胸径生长率模型。     

Modelling dominant height growth from national forest inventory individual tree data with short time series and large age errors

We developed dominant height growth models for Norway spruce (Picea abies (L.) Karst.) and Scots pine (Pinus sylvestris L.) in Norway using national forest inventory (NFI) data. The data were collected for a different purpose which potentially causes problems for dominant height growth modelling due to short time series and large age errors. We used the generalized algebraic difference approach and fitted 15 different models using nested regression techniques. Despite the potential problems of NFI data the models fitted to these data were unbiased for most of the age and site index range covered by the NFI data when tested against independent data from long-term experiments (LTE). Biased predictions for young stands and better site indices that are better represented in the LTE data, led us to fit models to a combined data set for unbiased predictions across the total data range. The models fitted to the combined data that were unbiased with little residual variation when tested against an independent data set based on stem analysis of 73 sample trees from southeastern Norway. No indications of regional differences in dominant height growth across Norway were detected. We tested whether the better growing conditions during the short time series (22 years) of the NFI data had affected our dominant height growth models relative to long-term growing conditions, but found only minor bias. The combination with LTE data that have been collected during a longer period (91 years) reduced this potential bias. The dominant height growth models presented here can be used as potential height growth models in individual tree-based forest growth models or as site index models.     

Evaluation of forest growth simulators with NFI permanent sample plot data from Finland

Tree-level and stand-level forest growth simulators and their combination were evaluated using data from a large network of permanent sample plots of the National Forest Inventory covering the whole of Southern Finland. The simulators were built up with the SIMO framework. The evaluation was carried out both at the stand-level and separately for Scots pine (Pinus sylvestris), Norway spruce (Picea abies), silver birch (Betula pendula) and white birch (Betula pubescens) strata within the plots. Effects of different factors, e.g. age, soil type, stand density and geographical location on the results were also analysed.     

Modeling diameter distributions of mixed-species forest stands

This study compares three diameter distribution models to fit mixed-species forest stands using four example plots with two or three species components in Daxing'an Mountain, PR China. The methods include (1) a finite mixture model (FMM) to fit two or three species components simultaneously, (2) a single Weibull function to fit the whole plot only, and (3) a single Weibull function to fit each species component separately and the summation of the individual species produced the whole plot. Our results indicated that Method 2 is only suitable to regular and unimodal diameter distributions with a balanced reversed J-shape. Method 3 may be able to fit each species component well if its frequency distribution is known and available in the data. However, Method 3 ignores the interspecies relationships within a given plot. Thus, the summation of the species components may not produce a good fit for the whole plot. In contrast, Method 1 (FMM) fits the species component distributions simultaneously with the constraint that the individual components add up to the whole plot, without requiring the observed frequencies for each species across the diameter classes. The FMM models are more flexible to describe highly skewed and irregular diameter distributions for the whole plot, as well as provide the acceptable estimation for each species component and the mixing proportions. Thus, the FMM models can be a useful tool for effectively managing mixed-species forest stands.     

直径生长潜力模型的研究

文章运用理查德生长曲线构成的遵守加法组合和乘法组合的非线性模型，对日本落叶松等3个树种进行了立地质量评价的尝试。结果表明，在森林立地质量评价的诸多方法之中，直径生长潜力仍然不失为一种应用简便和行之有效的方法。     

马尾松大径材优良家系幼林期生长表现

2011年于大型水库周围的湖南省青羊湖国有林场营造马尾松大径材家系试验林,造林半年和1年3个月后分别观测其幼林期的生长表现。结果表明:马尾松大径材家系幼林期的地径、树高以及冠幅生长量的差异均达到了极显著水平,不同家系地径、树高、冠幅的变异系数均在19%以上。不同年份间不同家系地径的变异系数大于树高的,地径的变异系数在年度间变化不明显,而树高的变异系数则2012年的明显小于2011年的。27个大径材优良家系造林1年3个月后,以80、425、38、34的生长表现最好,其树高、胸径和冠幅均生长良好;27个家系的树高生长量均超过了国家标准1年生树高的生长量,全部家系的平均树高远远超过国家标准1年生树高的生长量;34号家系的树高超过了国家标准2年生树高的生长量。马尾松大径材家系幼林期各生长性状,包括2011年地径、2012年地径、2011年树高、2012年树高、2012年冠幅等,除2011年地径与树高相关性不显著外,其余各因子间的相关性均达显著或极显著水平。     

长白山阔叶林高产大径木林分结构及择伐周期优化研究

以红石林业局为研究对象,建立了长白山林区阔叶林高产大径木收获量和净收益优化模型,其中包括矩阵生长子模型,采伐成本和林木价格子模型。通过大量的省级固定样地资料,对林分生长转移概率模型和进界生长模型进行了参数估计,并对模型进行了比较和修正。林分结构优化模拟时综合考虑了林木最大保留直径(LDT),相邻径级立木株数之比(q),林分保留断面积(RBA)和择伐采伐周期4个因素。模拟结果表明,高产大径木的林分结构参数为:q=1.2、LDT=46cm、RBA≥26m2,采伐周期(C)为10–20年。表9参9。     

不同栽植时期对苹果苗木成活及生长的影响

为了指导河北省滦平县的苹果栽植,以3a生国光苹果苗木为试材,研究了不同栽植时期苗木的成活率及生长情况,结果表明,4月8日栽植的苗木成活率、下部小主枝上的长梢数分别为92.67%、9.26个,极显著高于4月15日和4月22日栽植的处理;新梢平均长度为39.93cm,显著高于4月15日和4月22日栽植的处理;单株长梢数13.73个,显著高于4月22日栽植的处理。4月15日栽植的苗木成活率、下部小主枝萌芽率、下部小主枝上的长梢数分别为75.67%、39.71%、7.58个,极显著高于4月22日栽植的处理;单株中梢数为14.95个,显著高于4月22日栽植的处理。3个栽植时期的地径、单株短梢数和叶丛枝数无显著差异。表明4月8日栽植苹果苗木的生长情况优于后面的2个时期,在滦平县4月份内栽植苹果苗木应越早越好。     

东北过伐林区主要森林类型林分蓄积量生长模型

以吉林省汪清林业局金沟岭林场的主要森林类型为对象,基于小班调查数据,利用R ichards、Logistic、单分子、Gompertz和Korf 5种理论生长方程,建立了林分蓄积量生长模型,采用模型拟合统计量、误差及残差分布对模型进行评价和检验。结果表明:白桦林、人工混交林、天然针阔混交林用R ichards模型最好,人工落叶松林、阔叶混交林、天然针叶混交林用Logistic模型最好。研究结果为该地区森林生长预测和经营优化提供了参考和依据。     

湘西南大径级毛竹林生长特性研究

历时10年对大径级毛竹林进行培育试验,结果表明:大径级毛竹林发笋率、成竹率和大径级新竹数量比对照竹林分别增加1.30倍、1.31倍和16.07倍,大径级新竹数量占成竹总株数平均值为62.8%;大径级毛竹林平均胸径和最大胸径分别为12.28 cm、17.03 cm,平均枝下高和最大枝下高分别为8.95 m、13.0 m,立竹密度平均达到4 705株/hm2。大径级毛竹林中,产材量和各解析因子在一定范围内均随大径级毛竹比重的增大而不断增加,径级越大其增长幅度也越大。     

四种针叶低效林单株生长模型构建

以碳汇林基线情景低效针叶林,包括日本落叶松、杉木、马尾松、湿地松为研究对象,利用收集和调查的生物量与解析木实测数据,选择不同数学模型,通过曲线回归、非线性回归方法拟合模型参数,建立4个树种的单株生物量模型、胸径生长模型和树高生长模型。结果表明:4个树种的单株生物量模型、胸径生长模型采用相关系数较高、MSE值最小的幂函数模型、S模型拟合效果最好;4个树种的树高生长模型形式各异,日本落叶松、湿地松以Logistic模型拟合效果最好,杉木以抛物线模型拟合效果最好,马尾松以S模型拟合效果最好;检验结果表明,所建日本落叶松、杉木、马尾松、湿地松的生长模型预估精度均达到了95%以上,且都通过了F检验。     

杨树能源林各杨树品种生长节律研究

该文对杨树生物能源林参试品种不同密度的生长节律进行观测研究,得出杨树各品种树高和地径生长速峰期均处于6~8月份,与华北地区水、热同期,有利于生物量的积累;且地径生长高峰期比树高生长高峰期滞后或基本同步。对各品种不同密度的生长节律进行比较得出：不同密度对各杨树品种树高和地径的生长量有明显的影响,而对整个生长期内的生长节律无太大影响。     

森林资源档案管理系统中数据更新方法的探讨

森林资源档案管理系统主要对森林资源的档案信息进行管理,是林业信息管理中的重要内容。森林资源档案数据具有易变性和时效性,森林资源档案数据的及时更新将有助于林业主管部门对森林资源状况的掌握。本文综合了时空数据模型中基态修正模型、生命周期模型和面向对象模型的特点,建立了增量存储数据更新模型,提出了增量存储数据更新方法,并以甘肃省小陇山林业局党川林场的部分数据为基础,利用增量存储数据更新方法,对数据更新实现过程进行了探讨。     

A test of the accuracy of two individual tree growth functions for Picea abies

The accuracy of two distant‐independent diameter growth functions for individual trees of Picea abies L. (Karst.) are tested on plots older than 55 years b.h., and with relatively few trees per hectare. Both functions (I1 and I2) have site index, stand basal area, and individual tree basal area as explanatory variables; in addition age at breast height is used in Function I1. Relative to mean measured increment, Functions I1 and I2 underestimate the growth of the test plots by 4.4% and 10.9% respectively; Function I1 shows a root mean squared deviation of 29.2% for single plot predictions, and 5.4% for mean of all plots. Function II predicts the growth as well as some stand functions frequently in use in Norway. Function I2 is unacceptable because age is not an independent variable.     

大青杨胶合板用材林优树选择效果的评价

从营造胶合板用材林的角度出发,研究大青杨优树选择的可能性与效果,结果表明:7 a生无性系测定林的树高、胸径、材积生长量指标分别有110株、117株和102株,与对照达到极显著差异水平,有效选择率分别为91.7%、97.5%和85.0%;综合生长指标表现最为突出的前12个无性系依次为37号、20号、15号、25号、73号、94号、36号、65号、77号、84号、96号、107号;胸径的有效选择率和遗传力最高。     

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。     

不同间作模式对油茶幼林生长的影响

对不同间种模式(间种黄豆、西瓜、花生、松苗和不间种)油茶幼林的生长量情况进行分析比较得出,油茶新造林以间作花生和松苗较好,但是有间作植物的油茶林的成活率及生长量均低于未间作的油茶纯林。     

Aerial photo-interpretation using Z/I DMC images for estimation of forest variables

Abstract

Interpretation and tree height measurements in aerial photographs using photogrammetric workstations are frequently performed in standwise forest inventory. Images acquired by digital aerial cameras are now replacing the traditional film-based aerial photographs. In this study, digital images from the airborne Z/I DMC system for standwise estimation of stem volume, tree height and tree species composition were investigated at a 1200 ha forest area located in southern Sweden (58°30′N, 13°40′E). The 56 selected stands were dominated by Norway spruce [Picea abies (L.) Karst.] and Scots pine (Pinus sylvestris L.) with stem volume in the range of 30–630 m³ ha^?1 (average 300 m³ ha^?1) and tree height in the range of 6–28 m (average 20 m). The large-format pansharpened colour infrared images were captured at a flight altitude of 4800 m above ground level corresponding to a pixel size of 0.48 m. The photo-interpretation was conducted by four professional interpreters, independently. In particular, two different base-to-height ratios (i.e. the ratio between the ground distance between image centres at the time of exposure and the flight altitude above ground level) of 0.26 and 0.39 were evaluated, but no significant difference in the estimation accuracy for stem volume and tree height was found. The accuracy for stem volume estimation in terms of relative root mean square error, corrected for systematic errors, was on average 24% (in the range of 17–39%). The corresponding accuracy for tree height estimation was on average 1.4 m (in the range of 0.9–1.6 m). The tree species composition accuracy assessment using a fuzzy set evaluation procedure showed that 95% of the stands were correctly classified. The estimation accuracies are in agreement with previous results using conventional film-based aerial panchromatic photographs.