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1.
利用当地的2个刺槐品种与引进的2个刺槐品种进行留茬试验,通过造林成活率、苗高、地径、萌生株数及生物量对比分析,筛选出速生、萌芽能力强且生长良好的刺槐能源树种,为当地大力发展刺槐能源林提供理论依据。  相似文献   

2.
(一)子长县毛家河行政村,海拔1089~1323.3米。总土地面积26700亩,其中宜林面积13000亩,已造林6700亩,内有刺槐2700亩。该村1965年引入刺槐,在四旁零星栽植。1968年以每亩60~100株密度在山坡栽植30亩,生长迅速,很受群众喜爱。1976年,在反坡梯田上营造密度为330株刺槐林47亩。此后又营造密度60株、70株、100株、150株、200株、400株刺槐林2000多亩。密度不同生长状况差异很大,干部、群众褒贬不一,莫衷一是。为弄清哪种密度刺槐生长好,我们利用蹲点之便做了调查。现将调查结果叙述如下。1.房前屋后栽植生长快。芦岔河村薛秉章、毛家河村周培宽,1956年、1969年分别  相似文献   

3.
以河北太行山区4种典型水土保持林为研究对象,对混交林(栓皮栎-侧柏)、油松林、栓皮栎林和刺槐林的乔木层各器官生物量、含碳率以及碳储量进行比较研究。结果表明:混交林、油松林、栓皮栎林和刺槐林生物量分别为51.94,86.40,90.19,18.08t/hm^2,栓皮栎林和油松林生物量高于4种水土保持林生物量的均值(61.65t/hm^2),而混交林和刺槐林生物量分别占生物量均值的84.25%,29.33%。不同林分各器官在乔木层生物量中分配顺序均表现为树干>树根>树枝>树叶。4种典型林分各器官含碳率分别为45.16%~58.93%,58.48%~64.61%,51.16%~58.37%,52.35%~62.30%。4种典型林分碳储量为10.10~53.85t/hm^2。不同林分类型各器官碳储量与生物量呈正比关系,与生物量趋势基本相同,碳储量大小表现为油松林>栓皮栎林>混交林>刺槐林。  相似文献   

4.
对3个不同立地条件下刺槐无性系人工林生长量进行调查并对其生物量进行排序分析,结果表明,在荥阳地区,生物量排名前3的分别为:23号,豫刺槐4号和13号;在民权排名前3的分别为:13号,3-I和豫刺槐4号;在洛宁排名前3的分别为:3号,14号和豫刺槐4号。综合分析表明,豫刺槐4号在这3个地区生长最好,生物量最稳定,适宜在河南省作为能源林推广种植。  相似文献   

5.
以北京山区主要造林树种刺槐为研究对象,采用数量化理论Ⅰ的方法,通过研究不同立地因子对人工刺槐林高生长与径生长的影响来分析刺槐的适地性。结果表明:土壤厚度、坡度是制约人工刺槐林高生长的最重要因子,坡位、土壤类型是影响人工刺槐林高生长的重要因子;土壤厚度是制约人工刺槐林径生长的最重要因子,坡度是影响人工刺槐林径生长的重要因子。研究结果确定了影响北京山区刺槐人工林生长的主导因子,可以为刺槐造林地的选择和科学经营提供依据。  相似文献   

6.
依据60块标准地、420株标准木对太行山刺槐林分生物量进行了研究,现实林分的总生物量平均值为:4年生6.155t/ha,8年生22.304t/ha,13年生23.444t/ha,表明远远低于豫东平原刺槐林。6年生林分的净化率为300g/m~2·a,光合效率0·19%。本文建立的单株及林分生物量方程均具有较高的相关系数和估计精度。同时还就各器官生物量分配及叶枝比等问题进行了研究。  相似文献   

7.
以扬州城市绿化林带的3种常见树种——刺槐(Robinia pseudoacacia)、枫香(Liquidambar formosana)和银杏(Ginkgo biloba)为研究对象,研究了它们的林木生物量分配格局,并构建了器官及整株生物量异速生长模型。研究表明,随着林木的增大,这3种常见绿化树种的器官及整株生物量均呈增加之势。刺槐的树干生物量比例显著高于枫香和银杏,树枝和树叶比例显著小于枫香和银杏,但它们的树根比例之间并无显著差异。树种的地上生物量与地下生物量之间具有显著的数量关系,而且器官及整株生物量异速生长模型均达到显著性水平。与树干和树根相比,树枝和树叶的模型相对较差。考虑到基于胸径和胸径—树高的器官生物量模型之间的微小差异,利用胸径预测器官及整株生物量完全能够满足实际估测的需求,同时还能避免引入树高产生的预测误差。  相似文献   

8.
采用典型相关分析方法对影响辽宁省刺槐林分生长的生态因子进行分析,找出了制约刺槐林生长的主要生态因子,并提出了刺槐林适宜发展的区域和分布,为全省营造刺槐林提供依据。  相似文献   

9.
陕北黄土高原人工刺槐林生长与土壤干化的关系研究   总被引:25,自引:4,他引:25  
通过对陕北黄土高原南北 6个人工刺槐林样地进行标准地调查 ,结合树干解析与土壤含水量资料 ,分析了人工刺槐林树高、胸径、材积等指标的生长状况与土壤含水量亏缺的关系。结果表明 ,土壤含水量的亏缺程度与刺槐林的生长有明显的一致性。南部的宜君降雨充沛 ,土壤含水量基本没有亏缺 ,没有产生明显的土壤干化现象 ,相应刺槐林的生长状况良好 ,没有产生衰退迹象。随着降雨量的减少 ,从富县开始 ,土壤含水量发生了严重程度不一的亏缺现象。富县样地因水分亏缺而形成的干化层已影响到了人工刺槐林的生长 ,林分已有了衰退的迹象。样地吴旗、安塞、绥德和米脂则土壤含水量亏缺严重 ,形成了明显的土壤干化层 ,并且严重影响到了人工刺槐林的生长和发育 ,导致人工刺槐林成为低效低产林 ,限制了林分的生态防护效益 ,说明这些地区属于不适宜人工刺槐林生长的分布区。  相似文献   

10.
山地刺槐的高径生长主要集中在前10a,20a就可达到数量成熟,此时的木材只够小径材规格。根据山地刺槐林的生长规律,将其更新年龄定为10a为宜。刺槐萌芽更新容易,及时抚育定株,保留林地枯落物,是保证其迅速恢复成林并能旺盛生长的重要措施。  相似文献   

11.
Short rotation woody biofuel plantations on reclaimed surface mines in Appalachia can diversify domestic energy supplies and facilitate the reforestation of these disturbed lands. This study examined growth, survival, biomass accumulation and allocation, and nitrogen concentrations following two growing seasons in American sycamore (Platanus occidentalis L.) and black locust (Robinia pseudoacacia L.) seedlings receiving irrigation, granular fertilization, and irrigation + fertilization compared with untreated controls. Fertilization increased basal diameter, height, and stem mass of American sycamore following two growing seasons. Increased stem production was attributed to accelerated development and not shifts in biomass allocation due to treatment. Irrigation and irrigation + fertilization treatments did not enhance growth or biomass accumulation of American sycamore. Similarly, black locust basal diameter, height, and stem mass did not differ among the treatments. Browse surveys showed that more than 76% of black locust seedlings experienced arrested or retrogressed growth due to browse; less than 3% of American sycamores were browsed. This intensive browse by ungulates, likely including reintroduced elk, may have affected growth differences among species and confounded the effects of treatments on black locust. Survival was unaffected by treatment in both species, but mean survival was greatest in American sycamore (80%) compared to black locust (58%). Per tree total nitrogen uptake was highest in fertilized American sycamore (7.9 g) and lowest in irrigated American sycamore (0.9 g). The results of our study suggest that granular fertilizer applications can accelerate seedling growth on reclaimed surface mines in the Appalachian region.  相似文献   

12.
Ranchers need alternative livestock feeds when herbaceous forages become limiting in summer. Our objectives were to determine: (1) leaf and stem biomass components, (2) nutritive value [in vitro dry matter digestibility (IVDMD), total nonstructural carbohydrate (TNC), N, and N digestibility] of leaves for animal browse, (3) concentration of the secondary metabolites robinin and mimosine, and (4) in vitro leaf and bark toxicity for black locust (Robinia pseudoacacia L.) and mimosa (Albizia julibrissin Durz.), respectively, pollarded at 50 cm in Arkansas, USA. Black locust exceeded mimosa for every yield component (leaf mass tree−1, leaves shoot−1, shoots tree−1, shoot mass tree−1, stem basal area, and biomass tree−1) except mass leaf−1. Projected yields were 1,900 and 1,600 kg leaves ha−1 for black locust and mimosa, respectively, assuming a population of 12,300 trees ha−1. Mimosa leaves had greater IVDMD, TNC, and N digestibility than black locust. Mimosa leaves exceeded the nutritional N requirements of growing cattle (Bos taurus L.) and goats (Capra hircus L.), but protein supplementation would be needed for growing goats grazing black locust leaves. Tissue concentrations of secondary metabolites robinin and mimosine were below detectable limits in black locust and mimosa, respectively. The extract of black locust bark, but not leaves, was toxic to bioassayed African green monkey (Cercopithecus aethiops L.) cells. Either black locust or mimosa could provide moderate quantities of high quality, rotationally grazed forage for goats during summer months when herbaceous forage may in short supply.  相似文献   

13.
In Hungary, black locust (Robinia pseudoacacia L.) is one of the most important exotic species, forming entire stands. Its importance is increasing in many other countries. As a result of a new selection program eight black locust clones have been improved for establishing clone trials and a seed orchard. In this study juvenile growth and stem quality of micropropagated clones of black locust were evaluated on a marginal site in central Hungary. At ten years old, the clones ’MB17D3/4’ and ’PV201E2/4’ appeared to be especially promising for high quality wood production under arid hydrological conditions. A tissue culture method can be considered a suitable tool of propagating superior individual trees and offers new prospects for the rapid cloning of selected genotypes.  相似文献   

14.
匈牙利刺槐((RobiniapseudoacaciaL.)是在17世纪初从北美引入到欧洲的第一个森林树种。在匈牙利,刺槐是非常重要的速生树种,为经济和生态目的,可以成功营造刺槐人工林。结合该树种的生长特点选择营林措施,可以最大限度的提高刺槐人工林的成活率和生产力。本文根据林分结构和森林产量长期实验林的研究成果,提出了刺槐林的抚育作业次序。制定好的营林计划和模式将会培育出效益刺槐林,并能使土地经营者更好地接受该树种。同时,刺槐也是一个非常有用的能源生产树种,本文展示了对这方面的研究成果。图2表1参8。  相似文献   

15.
通过山西吉县黄土残垣沟壑区在 3种不同整地方式的林地上栽植同一规格的刺槐苗木 ,调查其成活率、生长量 ,结果表明 :刺槐在水平阶加坑整地上栽植 ,成活率比其它整地方式略高 ,而生长量则有明显优势 ,并在栽植的第 2年、第 4年生长量优势进一步扩大 ,对幼林的及早郁闭十分有利  相似文献   

16.
泾川县刺槐薪炭林生长状况分析   总被引:2,自引:0,他引:2  
通过对泾川县刺槐薪炭林的调查研究 ,分析其生长变化规律 ,并建立林分生长和采薪收获数学预测模型 ,为生产经营提供一定的科学依据  相似文献   

17.
太行山刺槐花量与蜜源林经营   总被引:1,自引:0,他引:1  
通过对大量标准地的调查研究表明,单株开花量主要受自身遗传因素的控制,单株在量为0-5.2kg/株,同一单株各年度的开花量也有较大变化。林分花量与林龄、林分平均胸径、林分平均高、林分优势木平均高、每公顷胸高断面积、每公顷蓄积、林分总生物量、林分干量、林分枝量、林分叶量、林分根量等林分因子均具有极显著的相关关系,通过逐步回归分析,筛选出影响林分花量的主要林分因子,并建立了林分花量的多元回归估测模型。林分花量生长动态符合生物增长的Logistic运动规律,其速生点为8a,速生期为4-12a,林分生长后期的花量动态与干、枝、叶、根等其它器官的生长动态存在显著差异,上述结论对蜜源林的经营具有重要意义。  相似文献   

18.
Black locust (Robinia pseudoacacia L.) is one of the most important stand-forming tree species in Hungary and its importance is increasing in many countries. The main aim of the discussed new selection programme is to identify black locust clones with good performance and good form for setting up clonal seed orchards. As a result of selection programme 16 new black locust clones have been improved. In spring 2002 a black locust seed orchard was established with the newly selected clones. About 40% of the plants can be considered to belong to the height growth rate class 1 and 2. Hungary was the first country where micropropagated black locust planting material was used for seed orchard establishment.  相似文献   

19.
Black locust (Robinia pseudoacacia L.) is one of the most important stand-forming tree species in Hungary and its importance is increasing in many countries. The main aim of the discussed new selection programme is to identify black locust clones with good performance and good form for setting up clonal seed orchards. As a result of selection programme 16 new black locust clones have been improved. In spring 2002 a black locust seed orchard was established with the newly selected clones. About 40% of the plants can be considered to belong to the height growth rate class 1 and 2. Hungary was the first country where micropropagated black locust planting material was used for seed orchard establishment.  相似文献   

20.
  • ? The alluvial forests of the Ticino valley have been greatly reduced in size and are now represented by only a small number of fragmented remnants. To study the natural development of the black locust, an invasive species, on relatively undisturbed lowland forests, two permanent plots were established in 2005 in the “Siro Negri” Forest Reserve.
  • ? The black locust became established almost exclusively between 1940 and 1960. The observed dynamic of the black locust in the Reserve was very similar to what has been observed in its native North American range: following the initial colonization, the black locust firmly established itself in the dominant and intermediate layers but did not regenerate. In addition to the absence of a significant younger population, the decline of the black locust is evident in an elevated mortality rate and higher proportion of black locust biomass in the total coarse woody debris (CWD)
  • ? Our results support the hypothesis that the best strategy to control the spread of black locust is to avoid disturbances that favour black locust colonization, and to wait for natural suppression of the species by other trees. Due to the lack of past reference conditions and the future uncertainties, ongoing monitoring will be needed to fully understand the dynamics of forest ecosystem change in the Reserve.
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