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1.
残次林迹地更新树种的研究   总被引:1,自引:0,他引:1  
1982 ̄1983年在本溪县偏岭乡新农村43.3hm^2残次林迹地植苗更新日本落叶松,色赤杨等7个树种试验。试验结果证明,残次林迹地更新7个树种保存率皆在86%以上,幼树生长发育良好。从立木材积生长量看,日本落叶松,色赤杨为最好,立木材积分别为刺楸,白桦,紫椴,水曲柳,红松的200.0% ̄988.2%和211.3% ̄1058.8%,其次是刺楸,白桦,再次是紫椴,水曲柳,红松。  相似文献   

2.
应用Shannon-Wiener多样性指数、均匀度指数和优势度指数等指标分析了辽宁东部山区人工营造34年生5种阔叶树水曲柳(Fraxinus manshufica Rup.)、刺楸(Kalopanax septemlobus)、紫椴(Tilia amurensis)、色赤杨(Alnus tinctoria Sarg)、白桦(Betula platyphylla Suk)与红松(Pinus koraiensis)形成的混交林及人工红松纯林内各层次植物物种多样性,结果表明:人工阔叶红松林内的植物种类数量与物种丰富度指数均高于红松纯林,其中以白桦-红松混交林中物种丰富度指数最大;乔木层的物种多样性以水曲柳-红松混交林最好,依次为白桦-红松、色赤杨-红松、紫椴-红松、刺楸-红松混交林、红松纯林;灌木层的物种多样性以水曲柳-红松混交林为最大,依次为紫椴-红松、刺楸-红松、白桦-红松混交林、红松纯林,色赤杨-红松混交林内灌木层的物种多样性最少;草本层的物种多样性以白桦-红松混交林为最大,依次为紫椴-红松、刺楸-红松、水曲柳-红松、色赤杨-红松混交林,红松纯林草本层的物种多样性最低。  相似文献   

3.
1982年营造红松、日本落叶松与色赤杨、白桦带、块状混交林20公顷,林龄7年时调查,幼林保存率平均85%以上,混交林中红松、日本落叶松5株优势木平均高分别为对照纯林的107.8%、115.7%;日本落叶松与色赤杨、白桦混交林蓄积生长量皆大于保留残次林7年蓄积的增长量,其中以12行日本落叶松与6行色赤杨混交林蓄积生长量最大,为日本落叶松纯林(对照)的142%,为7年生保留残次林蓄积增长量的606.1%。同时,混交林林地土壤得到了改善。  相似文献   

4.
该文对辽东山区人工营造20a生水曲柳、刺楸、紫椴、色赤杨、白桦5种阔叶树分别与红松形成的混交林及人工红松纯林进行了物种多样性分析。结果表明:人工阔叶红松混交林内,植物种类丰富,数量较多,红松纯林内的植物种类仅为人工阔叶红松林的42%~52%,植物总数量只有混交林的11%~37%;不同红松阔叶混交林乔木层物种多样性好于红松纯林,乔木层物种多样性指数排序为:红松×水曲柳﹥红松×刺楸﹥红松×紫椴﹥红松×色赤杨﹥红松×白桦﹥红松纯林。在灌木层中,各不同混交林物种多样性差异并不明显,且分布均匀。红松纯林灌木层物种种类、数量较少,但有明显的优势树种存在。在草本层中,各不同混交林植物种类分布相对均匀,各林型中丰富度指数,除红松纯林外,都在1.0以上。红松纯林草本层植物种类分布均匀,没有优势种存在。  相似文献   

5.
红松、日本落叶松与刺楸、水曲柳、紫椴、黄菠萝的带、块状混交试验林林龄10年时,各树种平均保存率均在85%以上。日本落叶松与刺楸等阔叶树混交林立木材积生长量,为日本落叶松纯林的82.2%~117.0%;红松与刺楸等阔叶树混交林立木材积生长量,为红松纯林的147.0%~327.0%。混交林有机质含量为纯林的106.2%~191.3%,全氮含量为纯林的116.7%~316.7%。  相似文献   

6.
红松,日本落叶松与刺楸等阔叶树混交造林技术的研究   总被引:5,自引:0,他引:5  
红松、日本落叶松与刺楸、水曲柳、紫椴、黄菠萝的带、块状混交试验林林龄10年时,各树种平均保存率均在85%以上。日本落叶松与刺楸等阔叶树混交林立木材积生长量,为日本落叶松纯林的82.2% ̄117.0%;红松与刺楸等阔叶树混交林立木材积生长量,为红松纯林的147.0% ̄327.0%。混交林有机质含量为纯林的106.2% ̄191.3%,全氮含量为纯林的116.7% ̄316.7%。  相似文献   

7.
日本落叶松与色赤杨、白桦混交林的综合效益   总被引:1,自引:0,他引:1  
通过对不同林型的试验表明,日本落叶松与白桦、色赤杨混交林型能促进林木的生长发育,各项性状指标均优于日本落叶松纯林。各混交林型能改善林分土壤状况,提高土壤肥力,在不同林型中,乔木层物种重要值,日本落叶松纯林最大,基本为一个林冠层,而混交林有2个林冠层,在灌木层和草本层中,以混交林型物种数量最多,远远高于日本落叶松纯林。混交林的物种丰富度最大,数量最多,纯林的总数量仅为混交林的11%~37%。  相似文献   

8.
涵养水源是森林生态系统的重要生态服务功能。该文以辽东山区人工阔叶红松混交林为研究对象,以红松纯林为对照,分析白桦、色赤杨、水曲柳、刺楸、紫椴与红松人工混交林的枯落物和土壤涵养水源能力。结果表明:红松纯林现存凋落物量明显高于人工阔叶红松林,红松纯林凋落物有效拦蓄量最高;5种不同类型的阔叶红松混交林的土壤持水能力、综合涵养水源功能均高于红松纯林。因此,在辽东地区应尽可能营造阔叶红松混交林。  相似文献   

9.
以辽东山区人工阔叶红松混交林为研究对象,以红松(Pinus koraiensis)纯林为对照,调查分析了红松-白桦(Betula platyphylla Suk.)、红松-色赤杨(Alnus tinctoria)、红松-水曲柳(Fraxinus mandshurica)、红松-刺楸(Kalopanax septemlobus)、红松-紫椴(Tilia amurensis)人工阔叶混交林的乔木层、灌木层、草本层及总生物量。结果表明:人工阔叶红松混交林总生物量的大小与混交林中与红松伴生的阔叶树种生长速度有关,如果伴生树种生长速度快于同龄红松生长,林地总生物量明显大于红松纯林;反之小于红松纯林。并且红松纯林内灌木层、草本层生物量低于各类型的阔叶红松混交林。  相似文献   

10.
[目的]探究美国白蛾(Hyphantria cunea)对不同寄主幼树的适生性,科学保护林木、防控美国白蛾。[方法]以东北地区广泛分布及栽植的8种树(家榆、胡桃楸、旱柳、白桦、水曲柳、长白落叶松、山槐、紫椴)为实验对象,室内饲养并测定美国白蛾幼虫取食不同寄主幼树叶片后的生长发育和营养效应指标。[结果]取食家榆和胡桃楸的美国白蛾幼虫存活率较高,其次是水曲柳、旱柳和紫椴;取食长白落叶松的较低,其次是山槐。取食家榆和胡桃楸的美国白蛾幼虫体重、体长、头壳宽数值较高,其次是水曲柳、紫椴;取食山槐的较低,其次是白桦。取食胡桃楸、家榆、水曲柳的美国白蛾幼虫化蛹率、羽化率数值较高,发育历期较短,其次是紫椴;取食长白落叶松和山槐不能化蛹,取食白桦、山槐、长白落叶松的不能羽化且发育历期较长。美国白蛾幼虫对家榆、胡桃楸、水曲柳取食量较大,其次是紫椴、旱柳;取食家榆和胡桃楸的幼虫食物利用率和食物转换率均处于较高水平,其次是紫椴、水曲柳;幼虫对山槐和白桦的取食量较低,其食物利用率和食物转换率均处于较低水平;幼虫食物消耗率与其食物利用率和食物转换率结果相反。[结论]家榆和胡桃楸较适合美国白蛾幼虫生长发育,其次是水...  相似文献   

11.
油松蒙古栎混交林细根生物量及养分现存量研究   总被引:1,自引:0,他引:1  
应用固定样地调查生物量的方法,在辽宁省建平县干旱所南大山试验区进行了油松蒙古栎混交林细根生物量和养分现存量的研究。结果表明,混交林的细根生物量大于油松纯林,两树种混栽后蒙古栎能促进油松的细根生长,提高油松细根生物量在混交林中的比例;混交林细根在各土层中分布得比纯林更均匀、更合理,两树种根系生长协调;混交林细根N、P养分现存量分别是纯林的1.1倍和1.2倍,可见混交林细根具有比纯林更高的养分积累和周转能力;纯林和混交林人工林的各径级活细根和死细根养分现存量都随细根径级的增加而减少,说明≤2 mm径级的细根在细根的养分循环中起主导作用。  相似文献   

12.
通过连续2年对岩桂人工林主要生长区降雨、地表径流、泥沙含量的观测和3种栽培模式水土流失的对比分析,得出了以下2个重要结论:①3年生林分与2年生林分比较,水土流失大为减少,岩桂纯林模式水土流失减少了91.81%,岩桂 白犀草模式减少水土流失为88.97%;②林草栽培模式较农耕地模式水土流失减少,岩桂纯林和岩桂 白犀草混交林模式水土流失均比未停耕农耕地有较大程度减少,2年生岩桂纯林水土流失减少35.3%,岩桂 白犀草混交林水土流失减少34%,3年生岩桂纯林水土流失减少88.11%,岩桂 白犀草混交林水土流失减少83.67%.  相似文献   

13.
对杉木人工纯林,杉木-马尾松、杉木-木荷、杉木-马尾松-木荷人工混交林的可燃物负荷量和生物质能进行了调查测定。结果表明:4个林分的可燃物负荷量和生物质能由高至低的顺序依次为:杉木-马尾松混交林、杉木-马尾松-木荷混交林、杉木人工纯林和杉木-木荷混交林。  相似文献   

14.
Tree plantations can be an important tool for restoration of abandoned pasturelands in the tropics. Plantations can help speed up secondary forest succession by improving soil conditions, attracting seed-dispersal agents, and providing shade necessary for understory growth. In this study, abundance and richness of understory regeneration was measured in three native tree plantations 15–16 years of age at La Selva Biological Station in the Costa Rican Caribbean lowlands. Each plantation contained tree species in pure plots, a mixture of the species, and natural regeneration plots (no trees planted). The greatest abundance of regeneration was found in the understory of pure plots of Jacaranda copaia (Aubl.) D.Don., Vochysia guatemalensis Donn.Sm., Dipteryx panamensis Benth, Vochysia ferruginea Mart., and in two mixed stands, while the lowest was found in the natural regeneration treatments with about half the values as in the plantation stands. There was a significant negative correlation between percent canopy openness and abundance of regeneration in the understory. Two distinctive clusters separated the regeneration treatments from the mixed and pure plantations at a very low Bray–Curtis similarity value. The natural regeneration treatments are separated from mixed and pure plantations in the two-dimensional ordination. The lack of difference between the understory make-up of pure and mixed plantations in abundance, species richness, and seed-dispersal syndromes of understory species suggests that planting mixed stands is not necessarily superior to planting pure stands for promoting understory diversity of woody species. While regeneration of woody species can be faster under pure- or mixed-species plantations than in open pastures, the abundance, richness and species composition depends on each plantation species, or species assemblages in case of the mixtures.  相似文献   

15.
杉木枫香混交林生长及其效应研究   总被引:1,自引:2,他引:1  
从林木生长及其与生态环境之间相互关系入手,对杉木枫香混交林与枫香、杉木纯林进行了定位调查研究。结果表明:混交林生长优势明显,有利于地力的维持和形成稳定的人工林群落。改善了林内的小气候条件和土壤的理化性状,是一种高产稳定、生态协调的人工针阔混交林类型,与杉木纯林相比,11年生混交林蓄积提高34.8%,土壤有机质含量增加43.3%,含氮量增加12.1%,速效氮、磷、钾含量分别增加11.5%、8.3%和11.3%。营造杉木枫香混交林是杉木纯林皆伐迹地更新,防治地力衰退的有效途径之一。  相似文献   

16.
马尾松与红锥混交异龄林生物量分配格局   总被引:2,自引:0,他引:2  
在经过三次抚育间伐的24 a生马尾松林下套种红锥,经过26 a的培育后形成了针阔混交异龄林。于2009年12月按相邻网格样方法设立固定样地(以50 a生马尾松纯林作对照),按径阶平均木法分别测定马尾松与红锥的林木生物量。结果表明:马尾松-红锥混交异龄林乔木层的生物量为220.072 t/hm2,比同龄马尾松纯林(241.618 t/hm2)的低8.92%;其净生产量为5.341 t/(hm2.a),比同龄马尾松纯林的高10.53%;其林分平均单株生物量比同龄马尾松纯林的低54.72%,且差异达到显著水平(P<0.05)。两种林分乔木层的生物量、净生产量和平均单株生物量的差异是由于林木年龄、林木保存密度及其分布不均匀性的共同影响结果。马尾松-红锥混交异龄林的地上部分生物量空间结构与马尾松纯林相比存在明显差异,混交林在树干高度6~8 m段开始出现枝叶,8~20 m段出现了枯枝,其枝叶生物量有两个峰值(14~16 m和20~22 m);纯林则在树干高度为8~10 m段开始出现枝叶,在10~20 m段出现了枯枝,其枝叶生物量只有一个峰值(20~22 m)。  相似文献   

17.
For several reasons the conversion of mono-species into mixed-species forests is presently a major concern of forest management and policy in Central Europe. Although it is possible to show a clear trend in favour of mixed-species forests, private forest owners and some forest economists have often not favoured mixed forests, assuming that they are less profitable. The trend towards mixed forests seems mainly for ecological reasons, while sound economic analysis of mixed forests is still rare. Based on this background the objective of the study is to answer the following four questions: (1) Does the yield of mixed-species forests differ from that of pure forests? (2) Does the mixing of tree species influence the ecological stability of forests? (3) Is the economic value of a mixed forest less than that of a monoculture? (4) How do forest economic models integrate the findings on yield and ecological stability of mixed forests? To answer these questions a literature review was conducted on the possible impacts of mixed-species forests. In comparison to pure stands a greater yield is not necessarily given in mixed stands. Yet, mixed-species stands are better able to compensate disturbances than monocultures. Moreover, there is substantial evidence that mixed-species stands are more resistant against biotic and abiotic disturbances. Applying an extended forest economic model, it was possible to demonstrate that mixing large blocks of native broadleaf species into pure conifer forests may lead to a significant reduction of financial risk. From a risk-averse perspective the economic value of a mixed-species forest may thus be greater than that of a mono-species forest. Yet, it became clear that forest economists do not often integrate the research findings on yield and ecological stability of mixed stands in modelling, but rather apply simple bioeconomic modelling. Moreover, in the context of mixed forests economists also largely ignore even classical financial approaches, which consider risk and risk preferences. We concluded that forest economics has to close substantial research gaps. Firstly, the knowledge of how to integrate biophysical properties of mixed forests in bioeconomic modelling is still an open question. Secondly, forest economists have to adopt the modern approaches of financial theory and management science to value mixed forests.  相似文献   

18.
选择福建省建阳范桥国有林场16年生杉木×闽粤栲混交林与杉木纯林为研究对象,对不同坡位不同林分养分积累量进行分析对比。结果表明:上坡立地条件下,杉木纯林乔木层N、P、K养分积累量均大于杉木×闽粤栲混交林。中坡和下坡林分乔木层养分积累量则表现为混交林大于杉木纯林。不同林分乔木层养分积累量均占整个林分养分积累总量的90%以上,且表现为N>K>P和下坡>中坡>上坡。上坡杉木纯林的灌木层和草本层N、P积累量均大于混交林,下坡林分的灌木层N、P、K养分积累量均表现为杉木×闽粤栲混交林大于杉木纯林。不同林分凋落物的N和P的积累量均大大超过草本层和灌木层的积累量。  相似文献   

19.
In process of ecological construction in typical region of upper reaches of Yangtze River, China, the mixed plantations at the ages of 10-20 present a trend to be pure forests and degeneration. Soil samples including stratified soil and total soil were taken from 4 typical profiles in the mixed plantation ofAlnus cremastogyne and Cupressus funebris in Yanting County in central Sichuan, China. Soil indices of the plantation were compared with those of natural forest in Gongga Mountain in the same region, The results revealed that structural quality of soil in plantation was significantly lower than that in natural forests. The degradation of structural quality of soil in plantation was one of key factors for plantation degeneration, The degradation causes of structural quality of soil were analyzed. Aanthtopogenic disturbance and absence of effective protection and scientific management are the main reason for degradation of structural quality of soil in plantation. The main countermeasures, e.g. foresl reservation, ecological rehabilitation, litter horizon rebuilding as well as organic fertilizer application, were proposed to improve the structural quality of soil in plantation.  相似文献   

20.
Photosynthetic Characteristics of Ash and Larch in Mixture and Pure stands   总被引:1,自引:0,他引:1  
IntroductionDuringthepasttwodecades,studieshaverevealedthatgrowingash(Fnainusmandshurica)andlarch(LarlksPP.)togetherinaproperwaycanincreasetheproduc-tivityQfthestandsI"'}'-'].Theyieldimprovementmechanismsattributetotwoaspects,i.e.,theabovegroundandundergr…  相似文献   

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