3S技术在风景园林中的应用现状与发展趋势

"3S"技术已经渗透到了环境、经济、社会等各个领域,对风景园林学科也有极重要的影响。主要论述3S技术在风景园林中的应用、目前存在的几点问题,提出3S技术在风景园林中应用的5个发展趋势,即:①由单一利用GIS技术进行研究工作向集成3S技术应用发展。②从大尺度向小尺度发展,3S技术将渗透到风景园林的各个层面。③从通用的GIS软件向专业的GIS应用软件过渡。④基于3S技术的数字园林逐渐建立,实现园林信息化管理,并从单机模式向网络发展。⑤基于GIS技术的城市园林绿地系统基础数据库逐渐建立。     

Foliage nutrient concentration and lopping time of agroforestry tree species in the Western Himalayan region of India

Tree foliage is a nutrient-rich and important source of green fodder to sustain the livestock during the lean winter period of a season in the low and mid hill regions of Indian Himalaya. Knowledge of the variations in mineral nutrient composition of the foliage during an active growth season helps in determining optimum lopping time to harvest nutrient-rich fodder. Changes in the nutrient concentrations of Albizia stipulata and Ougenia oojeinensis foliage during the annual growth season were studied to find out an optimum lopping time. Two dissimilar trends in variation of nutrients in foliage with the advancement of growth season were observed. These were: (1) depletion/dilution of N, P, K and S and (2) accumulation of Ca, Mg and Na. The depletion was more from October onwards, and accumulation reached to its maximum in November-December. Therefore, the period from October to December, preferably November, can be regarded as optimum lopping time for A. stipulata. For O. oojeinensis, the corresponding time could be September to November, preferably October. Ougenia foliage contained higher concentration of N, P, Ca, Mg, and Na than that of Albizia. This revised version was published online in June 2006 with corrections to the Cover Date. This revised version was published online in June 2006 with corrections to the Cover Date.     

A comparative study of above- and below-ground parameters of healthy and declining young Norway spruce trees in a mountain area affected by air pollution

The aim of this study was to characterize possible connections between above- and below-ground parameters and the decline of Norway spruce trees in the Jeseníky Mountains of the Czech Republic – an area affected both by long-term air pollution and subjected to liming. A part of this study was dedicated to soil analysis, which showed considerable changes in the soil environment and highlighted particularly high concentrations of magnesium and calcium, exceeding optimal limits by as much as 8 and 13 times, respectively. Our results suggest that the decline of evaluated trees is primarily connected to root system development, as we found no differences between evaluated above-ground parameters for either healthy or declining trees. Tree decline related directly to low numbers of skeletal roots, root origin and higher maximal angles between skeletal roots. Declining trees had on average five skeletal roots with maximal angles between them of 173^o, indicating poor mechanical stability. Regardless of tree vitality, 93% of all examined root systems were restricted to upper humus horizons with an average rooting depth of 10.2?cm. All evaluated trees showed severe root deformation into tangle, which suggests crucial influence of artificial planting on the architectural development of root systems.     

STUDY ON THE TREE GROWTH, ARCHITECTURE AND STAND STRUCTURE OF KOREAN PINE PLANTATION

lNTRODUCTIONTherhythInofKorcanpinegrowingandtrpearchitectUreissubjectedtoitsownl1crcd-ityandforeststructUre.Tl1cil11portantefTcctsofgapdynamicsarethereasonsthatmaketl1cKoreanpinetrceformhighqualityoftimbcr.Whilecurrentn1anagemcntofKoreanpincforestmainlyfocusesonpurestand,thccco-logicalrelationshipsbetWcenKoreanpineandothcrsPecicsinaconununityareneglected,thcprimitivebiologicalconditionislost.TheKo-reanpinetrecsinplantationcasilydivergeonthctOpofmainsten1,thesescverelyaITectthcgrOedqu…     

A review of tree fodder production and utilization within smallholder agroforestry systems in Kenya

Although the biological advantages in terms of animal production and improved soil fertility of the use of herbaceous legumes have been well demonstrated in Kenya and elsewhere, adoption by small-scale farmers has often been disappointing. This has led to increased research into the use of both indigenous and exotic fodder trees. In common with conventional pasture legumes, tree fodders contain high levels of crude protein and minerals and many show high levels of digestibility. They are readily accepted by livestock and presumably because of their deep-root systems, they continue to produce well into the dry season. Antinutritive factors can be a problem, however, and polyphenolics, toxic amino acids, cyanogenic glycosides and alkaloids are found in many tree species. There are abundant niches on small farms where fodder trees can be grown without affecting crop production. Although detailed management recommendations are lacking, guidelines exist with regard to appropriate cutting heights and harvesting frequencies. In the Embu region, it has been estimated that three kg of fresh fodder of Calliandra calothyrsus has the same effect on milk production as one kg of commercial dairy meal. Up to about 500 trees (250 m of hedgerow) will produce enough fodder to supplement one dairy cow for a complete lactation. The tree fodder can either replace the concentrate without loss of yield, or it can complement it to produce more milk. It is being enthusiastically adopted by small-scale farmers, many of whom are starting to produce their own seed. Other tree species are now being studied in order to avoid over-reliance on a single fodder species. This revised version was published online in August 2006 with corrections to the Cover Date.     

三个农林复合树种幼苗对施加磷肥的响应:生长和生节能力(英文)

对苗床培养的楹树、雨豆树和水黄皮袋装幼苗(6月龄)施以80kg·hm-2的磷酸盐,通过比较不同收获间隔期幼苗生长和生节情况,研究了施加磷肥对三个农林复合树种幼苗生长和生节作用。研究表明,施加磷肥显著促进雨豆树和水黄皮幼苗生长,但并未促进楹树幼苗生长。此外,施加磷肥还会显著增加楹树、雨豆树幼苗生节数和节大小,但对水黄皮幼苗作用较小,而且高收割间隔期会降低水黄皮生节表现。     

Gentan probability analysis with a state-dependent discrete forest growth model

The previous stochastic models applied for Gentan probability estimation utilized either a stationary or nonstationary Poisson process to describe the forest owners’ harvesting behavior by means of the counting process. A nonstationary Poisson process has the advantage over a stationary Poisson process of capturing a time-dependent change of harvesting events. However, a nonstationary Poisson process can lack one preferred characteristic of the probability theory when utilizing an average growth function with an asymptotic nature of growth. That is, the sum of the derived Gentan probabilities over time does not always become unity. In this paper, we introduce a state-dependent discrete forest growth model with an asymptotic nature of growth to overcome the problem, then propose a stochastic model applied for Gentan probability estimation. The Mitscherlich type growth function is utilized. The derived probability law to capture the harvesting behavior is shown to be the binomial probability law. The derived probabilities prove to sum up to unity over time.     

Virtual trees and light capture: a method for optimizing agroforestry stand design

In agroforestry systems, the distribution of light transmitted under tree canopies can be a limiting factor for the development of intercrops. The light available for intercrops depends on the quantity of light intercepted by tree canopies and, consequently, on the architecture of the tree species present. The influence of tree architecture on light transmission was analysed using dynamic 3D architectural models. The architectural analysis of Acacia mangium and Tectona grandis was performed in Indonesian agroforestry systems with trees aged from 1 to 3 years. 3D virtual trees were then generated with the AmapSim simulation software and 3D virtual experiments in which tree age, planting density, planting pattern and pruning intensity varied were reconstructed in order to simulate light available for the crop. Canopy closure of trees was more rapid in A. mangium than in T. grandis agroforestry systems; after 3 years the quantity of light available for A. mangium intercrops was three times lower than under T. grandis. Simulations with A. mangium showed that practices such as pruning and widening tree spacing enable to increase the total transmitted light within the stand. On T. grandis, modification of the tree row azimuth resulted in changes in the spatial and seasonal distribution of light available for the intercrops. These results are discussed in terms of agroforestry system management.

虚拟树木生长建模及可视化研究综述

虚拟树木,就是应用计算机模拟树木在三维空间中的生长发育状况,近年来已成为植物学、农林业、环境科学和计算机领域的研究热点.生长模型和可视化技术是它的核心内容.虚拟树木生长模型包括形态结构模型、功能模型和结构-功能模型等,其中结构-功能模型可以模拟树木与环境间的相互关系,其结果为树木的三维结构,因此它最为接近现实树木的生长,是虚拟树木生长模型的发展方向.树木形态的复杂性与计算时间和空间的矛盾一直是可视化研究中的难点.树木可视化还有不同于其他物体的特性,如多级分枝、枝条的弯曲、自相似、向光性、树木分枝间的光滑与非光滑连接等.树木可视化软件可分为2类:纯图形学软件和基于结构-功能模型的软件,其应用已涉及娱乐、商业、计算机辅助景观设计、教育、科研和林业生产等方面;但在树木构筑型数据的采集和管理、结构-功能模型的建立、树木可视化技术的研究及面向林业生产等方面仍需要大量的工作.     

Calibrating and testing a gap model for simulating forest management in the Oregon Coast Range

The complex mix of economic and ecological objectives facing today's forest managers necessitates the development of growth models with a capacity for simulating a wide range of forest conditions while producing outputs useful for economic analyses. We calibrated the gap model ZELIG to simulate stand-level forest development in the Oregon Coast Range as part of a landscape-scale assessment of different forest management strategies. Our goal was to incorporate the predictive ability of an empirical model with the flexibility of a forest succession model. We emphasized the development of commercial-aged stands of Douglas-fir, the dominant tree species in the study area and primary source of timber. In addition, we judged that the ecological approach of ZELIG would be robust to the variety of other forest conditions and practices encountered in the Coast Range, including mixed-species stands, small-scale gap formation, innovative silvicultural methods, and reserve areas where forests grow unmanaged for long periods of time. We parameterized the model to distinguish forest development among two ecoregions, three forest types and two site productivity classes using three data sources: chronosequences of forest inventory data, long-term research data, and simulations from an empirical growth-and-yield model. The calibrated model was tested with independent, long-term measurements from 11 Douglas-fir plots (6 unthinned, 5 thinned), 3 spruce-hemlock plots, and 1 red alder plot. ZELIG closely approximated developmental trajectories of basal area and large trees in the Douglas-fir plots. Differences between simulated and observed conifer basal area for these plots ranged from −2.6 to 2.4 m²/ha; differences in the number of trees/ha ≥50 cm dbh ranged from −8.8 to 7.3 tph. Achieving these results required the use of a diameter-growth multiplier, suggesting some underlying constraints on tree growth such as the temperature response function. ZELIG also tended to overestimate regeneration of shade-tolerant trees and underestimate total tree density (i.e., higher rates of tree mortality). However, comparisons with the chronosequences of forest inventory data indicated that the simulated data are within the range of variability observed in the Coast Range. Further exploration and improvement of ZELIG is warranted in three key areas: (1) modeling rapid rates of conifer tree growth without the need for a diameter-growth multiplier; (2) understanding and remedying rates of tree mortality that were higher than those observed in the independent data; and (3) improving the tree regeneration module to account for competition with understory vegetation.     

Dry matter production and nutrient cycling in agroforestry systems of mandarin grown in association with Albizia and mixed tree species

A study on dry matter production and nutrient cycling in agroforestry systems of mandarin grown in association with N₂-fixing Albizia and mixed tree species (non-N₂-fixing) was carried out in the Sikkim Himalaya. A site with Albizia was referred asAlbizia-mandarin stand and the other site with mixed tree species as mandarin stand. The stand total biomass, net primary productivity and mandarin fruit production was higher under the influence of Albizia. Agronomic yield of crops remained nearly the same in both the stands. Nitrogen and phosphorus concentrations of different components of Albizia were higher than those of mixed tree species, whereas their back translocation from leaf to branch before abscission was lower inAlbizia. The mandarin-based agroforestry is a highly nutrient-exhaustive system evaluated in terms of nutrient exit through the removal of agronomic yield. This system, under the influence of Albizia, was more productive with faster rates of nutrient cycling. Nutrient use efficiency increased under the influence of Albizia, in contrary to the hypothesis that efficiency should decrease with increasing rate of uptake. The poor nutrient conservation of Albizia, and malleability of nutrient cycling under its influence make it an excellent association which promotes higher availability and faster cycling of nutrients.Albizia should be utilised more extensively in the management of mandarin-based agroforestry systems.     

苏南地区高效降噪树种及其群落模式筛选

科学配置降噪植物是改善人居环境质量的有效途径.通过对符合生长要求的道路两侧纯林带和混交林带的噪音测试,结果表明,常绿大灌木如夹竹桃、珊瑚树等是降噪效果好的树种,常绿乔木必须和常绿灌木组合才能起到更好的降噪效果,而落叶树种在冬季降噪效果明显减弱甚至消失.通过筛选最后优选出降噪效果好的树种10种,降噪效果好的植物群落模式3个.     

Application of the pipe model theory to non-destructive estimation of leaf biomass and leaf area of pruned agroforestry trees

The relationship of branch cross sectional area (CS) to leaf biomass (LM) and leaf area (LA) was studied in three agroforestry tree species,Calliandra calothyrsus Maissn.,Erythrina berteroana Urban andErythrina poeppigiana (Walpers) O.F. Cook, to develop a non-destructive method for the estimation of LM and LA for trees managed with periodic pruning. Variation in these relationships was observed according to the bifurcation level and, in theErythrina spp., by clone. All the relationships were linear except the CS-LM relation in small branches ofE. poeppigiana, where it was initially exponential. At main branch level the relationship of CS to LM and LA was linear in all cases but the regression parameter values varied between species and clones, with determination coefficient (R²) 0.88–0.99. It was concluded that the ratio of main branch CS to LM and LA can be used for non-destructive estimation of the latter variables. The method has the additional benefit that the regression parameter value reflects the allocation of dry matter within a tree and, consequently, may give indications about its possible uses in different agroforestry systems.Work carried out at the Centro Agronómico Tropical de Investigación y Enseñanza (CATIE), Turrialba, Costa Rica.     

Trends in tree growth and understory yield in silvopastoral practices with southern pines

Farm-level simulators such as the Agroforestry Estate Model use as inputs either yield tables or outputs from forest modeling tools. Forest models rely upon assumptions on site index, stem diameter (DBH) distribution, wood production and tree mortality, which may or may not apply to agroforestry practices. Differences may arise because of the effects on tree growth of unusual spacings and configurations, fertilizer, pruning and grazing regimes, and tree-understory relationships as well. We examined data from published or existing field trials to determine mid- and long-term trends in tree growth and understory yields in silvopastoral practices with southern pines (Pinus spp.) in the United States. Tree DBH and height were greater in practices with improved pastures than in those with spontaneous grasses. Understory affected DBH more than height and, therefore, DBH-height relationships differed among practices. Sigmoidal models predicted that tree height will peak at different age depending on tree spacing and understory type. These changes may affect the accuracy of site indices and wood yield predictions. Livestock gains decrease linearly with increasing stand basal area and stand age, although forage yields sometimes decay exponentially. In one of the experiments, livestock gains decreased to almost zero at age 19 but with stand basal areas at that age markedly differing (14 and 25 m² ha^–1) for two different spacings. Additional data would allow to generate empirical algorithms to obtain farm-level simulations of broad application, improve economic analysis and generate hypotheses to guide future experimental work. This revised version was published online in August 2006 with corrections to the Cover Date.     

碳汇林主要建群种树高和胸径生长模型构建

依据湖南省碳汇林的主要类型,利用"八五"到"十二五"期间课题组自有研究成果,并进行补充调查;以碳汇林的17个主要建群种作为研究对象,综合考虑林分类型、立地状况、群落结构等因子布设固定样地194个,按径阶组划分不同的树高级用以选取目标径阶标准样木共计1 098个,采用树干解析木法,利用Richard、Logistic、Korf、Mitscherlich、Schumacher、Weibull等6种理论生长方程分别进行拟合。得出拟合效果最优的主要建群种树高和胸径生长模型,所有最优模型相关系数均达到了0.9以上,通过评价与检验,各模型均具有较好的拟合精度和预估水平。     

Modelling agroforestry systems of cacao (Theobroma cacao) with laurel (Cordia alliodora) and poro (Erythrina poeppigiana) in Costa Rica

The agroforestry systems of cacao (Theobroma cacao) under laurel (Cordia alliodora) and cacao under poro (Erythrina poeppigiana) were studied at CATIE, Turrialba, Costa Rica. An inventory was taken of the organic matter and nutrients (N, P, K, Ca, and Mg) separating the species into their compartments (leaves, branches, trunks and roots). Studies of the litter and of the mineral soil (0–45 cm) yielded these results: Patterns of nutrient accumulation are discussed in relation to the characteristics of these agroforestry systems.     

杨树开花飞絮生物化学控制技术的初步研究

通过对植物生长调节物质IAA、ETH、GA3、PP333的筛选和应用技术的研究，从中选择出对小黑杨雌株控经高的药剂、施药剂量、施药方法和施药时期，以便为解决东北地区主要城市绿化树种－－杨树的开花飞娟污染问题提供实用技术。结果表明：在秋季花芽分化前期树干注射200mg/株的GA3效果很好，控花率均达到88％以上，小径级的可达到1005；其它的药剂及处理控花率低，效果不明显。     

幼树阶段杉木不同无性系生长与形态性状分析

杉木是我国南方最重要的造林树种之一,在木材安全重大战略中具有举足轻重的地位。株型是决定杉木产量的核心要素,掌握理想株型的性状组成对提高杉木产量具有重要的意义。本研究对来自福建省洋口国有林场的14个杉木组培无性系造林后3 a内生长量和造林后第2年的形态指标进行比较与分析,研究试验林分郁闭前幼树阶段的形态与和生长特点以及它们之间的关系,为杉木理想型无性系的选择和不同株型的定向培育方法提供理论依据。结果表明:1)造林后1至3年林分树高的平均值分别为1.00、2.52和3.87 m,第3年的胸径平均值为4.76 cm,无性系的树高生长变异系数随着生长时间的增长呈下降的趋势,不同无性系的生长量之间存在极显著的差异;其中除020在高生长上优势明显外,054、061、063和023在3 a内的树高和胸径生长均具有较大的优势。2)造林后第2年坐生密度、冠幅、枝盘数、当年生节间距离、一级侧枝数和年盘二级分枝数的平均值分别为63.58片、176.1 cm、6.11、21.76 cm、21.02和19.88,且不同无性系之间存在极显著的差异;说明杉木株型之间的差异较大。3)通过聚类分析将无性系063、054及061归为浓密型杉木,无性系047、148、023及049归为稀疏型。4)生长与形态之间的相关性分析表明浓密型杉木的生长量更大,根据以上的分析初步认定,在生长初期,杉木的理想株型具有枝条浓密和冠幅宽大的特点。     

A simulation model for evaluating technical and economic aspects of an industrial eucalyptus-based agroforestry system in Minas Gerais, Brazil

This study analyses the economic aspects of a eucalypt-based agroforestry system established in the savanna region of Brazil. In 1993,eucalypt clones were planted at a spacing of 10 × 4 m, to facilitate their future association with crops and pasture grasses. The results show that the establishment and maintenance costs represent 37% of the total costs associated with the system. More than half of the revenues are from the sale of the wood products obtained in the 11-year rotation. Variations of ±20% of the sale price of the cattle significantly affected the sensitivity analysis, closely followed by the variations of the price of wood for lumber and energy. Variations of ±20% of the establishment costs of the forest component significantly affected the economic indicators. The viability of the system is also sensitive to a slight change in interest rate. Finally, the agroforestry system adopted by the company is economically more attractive than eucalypt monoculture.This revised version was published online in November 2005 with corrections to the Cover Date.