不同施肥量对油茶6年生幼林营养生长的影响

在广西巴马县选取6年生的油茶人工林为研究对象,连续3年开展不同施肥量(0.25kg/株、0.50kg/株、0.75kg/株、1.00kg/株、1.25kg/株和不施肥)对油茶中幼林树高、地径、冠幅的影响研究。试验共设6个处理,分别是处理1(0.25kg/株)、处理2(0.50kg/株)、处理3(0.75kg/株)、处理4(1.00kg/株)、处理5(1.25kg/株)和处理CK(不施肥)。结果表明,各施肥处理对油茶中幼林的树高、地径、冠幅增长表现不一致。其中,处理CK对各营养生长指标的影响效果最小;施肥量为1.00kg/株的处理对油茶树高生长的促进效果最大;施肥量为0.50kg/株的处理对油茶地径、冠幅生长的促进效果最大。综合考虑施肥成本和生长情况,以0.50kg/株的施肥量对油茶人工幼林营养生长的促进效果最佳。     

湘西喀斯特地区不同种类基肥对青钱柳幼林 生长量影响研究

采用随机完全区组设计、在同一立地条件下,系统研究了不同种类基肥对三年生青钱柳幼林地径、树高和干叶重量的影响。通过施用不同种类基肥与对照相比,得出结论:青钱柳幼林地径、树高和干叶重量存在显著性差异。施用复合肥、有机肥、钾肥基肥与对照相比,青钱柳幼林地径增长率分别为82. 1%、50. 4%、49. 6%;青钱柳幼林树高增长率分别为78. 9%、63. 9%、63. 3%;青钱柳幼林干叶重量分别增加846. 47%、850. 18%、595. 23%;枯饼肥、磷肥与对照相比,地径、树高生长和干叶重量无明显影响。     

施肥对油茶幼林营养生长的影响

对长林系列油茶无性系分别施有机肥、复合肥、尿素,环状沟施或散施处理,观测各无性系树高、冠幅、地径、新梢长度的生长量指标并进行分析,结果表明:不同追肥处理对油茶幼林树高、冠幅等营养生长性状有显著影响:3种肥料对油茶幼林营养生长的促进作用有机肥＞复合肥＞尿素;不同施肥对油茶幼林营养生长的促进作用冠幅＞树高＞新梢长＞地径;沟施效果好于散施.     

不同沼液用量对油茶生长及果实品质的影响

为给沼液的合理利用提供科学依据,以6年生油茶林为试验材料,采用随机区组试验设计,设置了B0(0 kg/株,对照组)、B1(10 kg/株)、B2(20 kg/株)、B3(30 kg/株)、B4(40 kg/株)共5个试验组,就不同沼液用量对油茶生长及果实品质的影响情况进行了试验。结果表明:施用沼液能有效促进油茶的营养生长,对油茶地径增长和冠幅增长的影响均达到了显著水平。B2处理和B3处理的单株产量比对照组分别增长了25.45%和4.1%。5个处理组中,B3处理对油茶果实品质的效果最好,与对照相比,B3处理的单果质量增加了8.83%,其横径增加了10.21%,其纵径提高了9.37%。文中还对油茶产量与其各营养生长指标间的相关性进行了分析,结果表明,树高增长量对油茶产量的相关性最大。综合分析认为,B3(30 kg/株)处理最能有效促进油茶生长,提高油茶产量。     

不同经营措施对龙眼茶生长影响试验

通过施不同基肥、采用不同抚育措施对龙眼茶生长影响的对比试验,结果表明,施5kg鸡鸭粪作基肥对龙眼茶的生长影响最大,3年生样株高112.0cm,冠幅0.97m2,分别是对照组的200.0％和231.0％;每年2次松土除草,并追肥2次,对龙眼茶的生长影响最大,3年生样株高、地径、冠幅分别是对照组的208.1％、206.7％、185.3％.     

基肥对西南桦幼林生长的影响

以N、P、K肥为基肥,采用单因素随机区组设计,对西南桦幼林进行施肥试验。结果表明:在基肥施用量为0~200 g/株的范围内,树高和地径的生长量均随着基肥量的增加而增大;不同基肥施用量的处理间树高和胸径均存在极显著差异,树高和地径生长较好的处理均是基肥施用量为200 g/株的处理,树高和地径生长较差的处理均是不施肥的处理。     

配方施肥对油茶优良无性系生长和产量的影响

本实验以油茶优良无性系长林40号为试材,通过不同肥料类型和不同配方对油茶新造林进行正交施肥,分析了不同处理对油茶生长和产量的影响。结果表明:合理的施肥配比在促进油茶生长的同时也能显著提高油茶的产量。研究中最佳配方施肥方案为造林第1年每株施加0.5kg磷肥+0.4kg复合肥+0.3kg;钾肥(基肥);第2-4年分别每株施复合肥0.1kg(追肥)、鸡粪0.5kg(追肥)、复合肥0.3kg(追肥)。     

油茶幼林施肥试验

选用氮肥、磷肥和钾肥3种肥料,采用3因素4水平试验设计,同时,单位面积配施相同施肥量的有机肥,2013年、2014年连续2年对油茶幼林进行施肥试验,共设11个处理;2012年、2013年、2014年分别观测树高、地径和冠幅,分析不同施肥处理对油茶幼林营养生长的影响。结果表明,连续2年施肥后,磷肥和钾肥相同的处理,其2年的树高的增长量均随着氮肥施用量的增加而加大;氮肥和钾肥相同的处理,其2年的树高、地径和冠幅的增长量均随着磷肥施用量的增加而加大;氮肥、磷肥相同的处理,其2年的树高、地径和冠幅的增长量均随着钾肥施用量的增加而加大;氮肥对地径和冠幅的影响规律性不明显。施肥效果最好的处理是配方中钾肥施用量最大的处理。建立的氮肥、磷肥和钾肥效应模型得出的最佳施肥量为:氮肥15.7 kg/667 m2、磷11.6 kg/667 m2、钾13.2 kg/667 m2。     

不同肥料类型对幼龄油茶生长的影响

为了给幼龄油茶的施肥提供依据,采用随机区组设计,设置果满多、上海大颂生物菌肥、希星油茶专用肥、江西绿园油茶有机专用肥、复合肥共5个施肥处理和不施肥对照,对江西奉新县幼龄油茶进行了施肥试验。调查株高、地径、冠幅、梢长、梢直径和叶绿度等指标,并分析了它们之间的关系。结果表明,施加不同类型的肥料与油茶株高、地径、冠幅、梢长、梢直径及叶绿度均呈现一定的相关性,施肥对于油茶的株高、春梢长、春梢直径及叶绿度均存在显著的影响,而油茶冠幅和地径与施肥无显著关系;在对油茶株高、地径、冠幅和春梢长度的促进作用上,以上海大颂生物菌肥为最好;在对油茶春梢直径和叶绿度的影响上,以果满多效果为最好。所以在生产上为促进油茶生长,推荐应用上海大颂生物菌肥或果满多。     

湿地松人工幼林施肥生长节律研究初报

两年试验观测表明，湿地松幼林施基肥效明显优于迫肥，施ＮＰ、ＰＫ、ＮＰＫ等配比肥优于单一肥种，Ｐ肥肥效估于Ｋ、Ｎ肥，追施Ｎ、Ｋ肥出现负效应；对其生长量进行研究，结果表明，湿地松幼林生长呈双峰趋势，４月和７月为生长高峰期，造林当年施入ＮＰ、ＮＰＫ等配比肥，次年生长可维持３个月的高峰期，造林当年施入ＮＰ、ＮＰＫ做基肥或次年４月份前施入适量Ｐ肥，均可使肥效得到充分发挥。     

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。     

Phenological variation in height and diameter growth in provenances and families of loblolly pine

The phenology of 5- and 6-year old loblolly pine (Pinus taeda L.) trees was studied over two different growing seasons (1993 and 94) in southwest Georgia. These trees were from 7–9 open-pollinated families from each of four different provenances planted at two locations. The provenances were: Atlantic Coastal Plain (eastern SC), Gulf Hammock (north FL), Lower Gulf (south AL, MS) and Upper Gulf (north AL, MS). Provenances did not vary as to when height growth started in spring, but showed very significant differences for the date of growth cessation in fall. The Gulf Hammock source grew the most and also had the longest height growth period, while the Upper Gulf source was first to stop height growth and had the least annual height increment. Provenances were also significantly different for the date of cessation of diameter growth (a difference of 22 days between Gulf Hammock and Upper Gulf), and the order of cessation was the same as for height. Families within provenances were significantly different for date of cessation of height growth and diameter growth. When family means were considered across provenances, there was a correlation of 0.69 (p-value = 0.0001) between annual height increment and date of height growth cessation. There was a weaker association between faster growth and a longer growing season within provenances.     

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。     

A diameter growth index method for standardization of forest data inventoried at different dates

A model of tree diameter growth during the growth season was developed to standardize the forest data from different inventory dates. A diameter growth index is defined and its relation with the number of growing days is established. Parameters characterizing this relationship are estimated using accurate tree ring width measurements and other stand and tree related variables from the Swedish National Forest Inventory data for 1989. The residual analyses show that the model is an effective expression of the actual growth and the results are consistent with an earlier used tree growth model. Some climatic data are tested for model improvement, but no essential improvement is gained given the data available.     

林分未来直径分布预估精度的研究

为了给森林资源经营、管理提供指导,利用3块编号固定标准地调查资料,对常用的均匀分布、Meyer修正数据、累积分布曲线法等几种未来直径分布预估法进行了分析。结果表明,各种方法适应性都很强,其中以累积分布曲线法的精度最高,其精度是82.7%。     

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。     

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。     

Do individual-tree growth models correctly represent height:diameter ratios of Norway spruce and Scots pine?

Height:diameter ratios are an important measure of stand stability. Because of the importance of height:diameter ratios for forest management, individual-tree growth models should correctly depict height:diameter ratios. In particular, (i) height:diameter ratios should not exceed that of very dense stands, (ii) height:diameter ratios should not fall below that of open-grown trees, (iii) height:diameter ratios should decrease with increasing spacing, (iv) height:diameter ratios for suppressed trees should be higher than ratios for dominant trees. We evaluated the prediction of height:diameter ratios by running four commonly used individual-tree growth models in central Europe: BWIN, Moses, Silva and Prognaus. They represent different subtypes of individual-tree growth models, namely models with and without an explicit growth potential and models that are either distance-dependent (spatial) or distance-independent (non-spatial). Note that none of these simulators predict height:diameter ratios directly. We began by building a generic simulator that contained the relevant equations for diameter increment, height increment, and crown size for each of the four simulators. The relevant measures of competition, site characteristics, and stand statistics were also coded. The advantage of this simulator was that it ensured that no additional constraint was being imposed on the growth equations, and that initial conditions were identical. We then simulated growth for a 15- and 30-year period for Austrian permanent research plots in Arnoldstein and in Litschau, which represent stands at different age-classes and densities. We also simulated growth of open-grown trees and compared the results to the literature. We found that the general pattern of height:diameter ratios was correctly predicted by all four individual-tree growth models, with height:diameter ratios above that of open-grown trees and below that of very dense stands. All models showed a decrease of height:diameter ratios with age and an increase with stand density. Also, the height:diameter ratios of dominant trees were always lower than that of mean trees. Although in some cases the observed and predicted height:diameter ratios matched well, there were cases where discrepancies between observed and predicted height:diameter ratios would be unacceptable for practical management predictions.     

兴安落叶松林分直径结构研究

通过对大兴安岭原始兴安落叶松林分直径结构进行研究,分析兴安落叶松林和白桦林木株数和蓄积按径阶分布的特点。分析结果表明:兴安落叶松林分总体上表现出较明显的原始天然异龄林特点,直径分布结构符合原始天然林的自然生长规律,总体上呈波动的倒"J"字型曲线,这可能是由于该林分中林木的生物学特性和生境共同作用的结果。该研究为科学经营提供理论依据。     

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.