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辽宁红松,樟子松,落叶松人工中幼林抚育间伐效益分析 总被引：2，自引：0，他引：2
红松、樟子松、落叶松是辽宁三大用材树种、８０年代初对红松、樟了松、落叶松人工中幼林抚育间伐，开展了定位与半定位的试验研究，历经１０余年，取得了一定的效果。本文介绍和描述了红松、樟子松、落叶松人工中的幼林有间代取得的经济、生态、社会效益，为今后开展三树种人工林的抚育间伐工作，及指导林业生产提供理论依据。 相似文献
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红松是我国珍贵的用材树种之一,由于树干通直,材质良好,出材率高,耐腐力强,工艺价值极高.种子味美,含油率高达70%以上,营养价值高,种仁成为很好的保健食品.为提高红松造林质量,结合生产实践,总结出红松山地育苗从种源、圃地选地、种子处理、播种到田间管理等技术措施,为营造优质高效的红松果材林提供优质壮苗. 相似文献
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长白落叶松、红松是辽东山区的乡土树种。根据对新宾县关家林场的长白落叶松与红松混交林的林分生长调查,红松与长白落叶松混交形成的林分较稳定且长势较好,在生长过程中,林分内侵入一部分阔叶树种。林龄24a生时,树种组成为5长白落叶松4红松1杂,进行第1次抚育间伐,抚育后,林分蓄积年均增长6 63 hm2·a。林龄38a生时,树种组成为6红松3落叶松1杂,与同龄、立地条件相似的长白落叶松、红松纯林相比,林分蓄积量增加20 6805 hm2和38 3730 hm2。 相似文献
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红松（pinus koraiensis）是我国北方珍贵的林木种子资源,是北温带针叶林带著名的树种,该树种极耐寒、喜湿、喜光,成活率高,是优良的用材及用种树种,各相指标均优于西伯利亚红松。 相似文献
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西伯利亚红松在新疆仅分布于布尔津林区的哈纳斯河和柯姆河上游谷地、哈巴河林区的白哈巴两地，是珍贵的稀有树种。在海拔1600m-2400m的高度同落叶松、冷杉混交形成亚高山带重要水源涵养林。为了研究西伯利亚红松在其他生境的适应情况，培育红松人工林，我们在贾登峪苗圃(海拔1461米)进行了播种育苗试验。 相似文献
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世界松籽资源生产利用现状及我国松籽发展对策探讨 总被引：2，自引：1，他引：1
松籽是一种美味的非木质林产品, 全球有30多个松属物种可以生产可食用松籽, 但目前只有5个物种的松籽被用于商业生产。近年来, 国际松籽市场规模在不断扩大, 产品供不应求, 价格居高不下。我国是松籽生产及进出口大国, 年产量在2万t左右, 出口量占世界松籽贸易量的40%以上, 居首位, 但出口的松籽多数原产于俄罗斯。近几年俄罗斯国内消费量在不断增长, 加之俄罗斯远东及西伯利亚生产松籽的森林被大面积地砍伐破坏, 我国不可能长期依赖进口满足国内消费及出口需求。因此, 建议对我国果用松林的经济与生态重要性进行再评估, 并考虑起动相关研究, 挖掘潜力, 对生产松籽的松林实施园艺式高效经营或作为专门产业来管理。 相似文献
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优良红松坚果型优树的选择方法(英文) 总被引：3，自引：0，他引：3
于1988-1998 年对长白山、小兴安岭和完达山地区天然红松林以及黑龙江省鹤岗地区人工红松林结实量进行了实地调查和测定。根据调查和测定数据，对红松结实特征，包括结实量、球果长度、球果数量、出种率，种子千粒重、种子产量、种子大小、种子空实率、球果虫害率、结实指数等，进行分析方差分析、多重比较和逐步回归，得出各项结实因子对结实量的贡献率，将球果长度、千粒重和出种率确定为优树选择的重要指标，然后采用加权系数法确定红松坚果型优树，并制订出天然红松林坚果型优树标准和红松人工林坚果优树标准。本项研究为建立红松坚果园选择优树提供了方法和标准。 相似文献
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Yoichi Kishi 《Journal of Forest Research》1999,4(4):287-290
The total area ofPinus densiflora andP. thunbergii forests in Ibaraki Prefecture in 1978 was 65,200 ha, which decreased to 30,300 ha by 1985 mainly due to pine wilt mortality
caused byBursaphelenchus xylophilus. This damage has also continued thereafter. To estimate the survivability of pine trees in Ibaraki Prefecture, pine tree
mortality has been studied in eight experimental forests for over 20 years, and ground surveys throughout the Prefecture were
also conducted in 1995. Survival in the experimental forests corresponded well to the results of ground surveys. Pine forests
remained as pure stands if control measures were undertaken or if they were located in cool areas. In warm areas where no
control was undertaken, most of the pine forests disappeared and only a few pine trees remained in mixed forests, while on
dry soils no mature or old pine trees survived. Since surviving pine forests are often cut for wood utilization,P. densiflora andP. thunbergii may decrease in area to become rare species in the future unless controls are applied and/or reforestation with resistant
pines is carried out.
A part of this paper was orally presented at the 108th Annual Meeting of the Japanese Forestry Society (1997). 相似文献
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Ana Cristina Silva Joana Henriques Eugnio Diogo Ana Paula Ramos Helena Bragana 《Forest Pathology》2020,50(1)
The fungus Sydowia polyspora is frequently isolated from conifers worldwide and is considered a pathogen on several hosts. Stone pine (Pinus pinea) is one of the most important forestry species throughout the Mediterranean basin due to the value of the edible pine nut. Stone pines showing tip dieback, needles with tan‐ to yellow‐coloured lesions and shoot death, observed in stands in Portugal, were sampled for analysis. Fungal colonies covered with cream‐coloured spore masses, were consistently obtained. Morphological and phylogenetic analyses of the ITS rDNA region enabled identification of these isolates as S. polyspora. Inoculation tests showed that the fungus caused lesions on excised P. pinea shoots. The symptoms observed might have a negative effect on pine nut production, and thus, evaluation of the impact of this disease is of relevance to future research. This paper is the first to report S. polyspora causing disease on P. pinea. 相似文献
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An understanding of the inter-relationships between the traits characterising tree-to-tree variation in fruits and kernels
is fundamental to the development of selected cultivars based on multiple trait selection. Using data from previously characterised
marula (Sclerocarya birrea) trees in Bushbuckridge, South Africa and North Central Region of Namibia, this study examines the relationships between
the different traits (fruit pulp, flesh/juice mass, and nut shell and kernel mass) as a means to determine the opportunities
to develop cultivars. Strong and highly significant relationships were found between fruit mass and pulp mass in trees from
South Africa and Namibia, indicating that size is a good predictor of fruit pulp production. However, fruit size is not a
good predictor of nut or kernel production, as there were weak relationships between fruit and nut and/or kernel mass, which
varied between sites and landuses. Generally, the relationships between fruit mass and kernel mass were weaker than between
fruit mass and nut mass. Relationships between kernel mass and shell mass were generally weak. The lack of strong relationships
between fruit and kernel mass does, however, imply that there are opportunities to identify trees with either big fruits/small
nuts for pulp production, or trees with large kernels in relatively small fruits for kernel oil production. However, within
fruits from the same tree, nuts could contain 0–4 kernels, indicating that even in trees with an inherent propensity for large
kernels, improved pollination may be required to maximise kernel mass through an increase in kernel number. Finally, the relationships
between percentage kernel oil content and the measured morphological traits were also very weak. The conclusions of these
results are that there is merit in identifying different combinations of traits for the selection of trees producing either
pulp or kernels. Consequently, fruit and kernel ‘ideotypes’ are presented as guides to the selection of elite trees for cultivar
development. These results have important implications for the domestication of the species as a producer of fruits or kernels
for food/beverages or cosmetic oils. 相似文献
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The consumption of the pine needles and the stripping of bark by sheep grazing annual pastures in three open stands of P. radiata and one of P. pinaster were measured. The P. radiata were four years old and the densities were 250, 500 and 750 trees ha-1. The P. pinaster included two, three and four year-old trees and the density was 440 trees ha–1.Needles were eaten immediately after the sheep were admitted and this continued throughout the year. Within ten weeks of the start of winter grazing, sheep stocked at 7–10 ha–1 had eaten about half of the accessible needles on both species where densities were less than500 trees ha–1. The estimated consumption was about 260 g sheep–1 day–1 for the P. radiata. Bark stripping then commenced and continued throughout spring and summer on most plots. In some plots at low tree density, bark was stripped from more than 35% of the trees. In denser stands, needle consumption per tree was less and bark was stripped from less than 5% of the trees.Bark damage was most common on the smaller trees, and severity of stripping was negatively correlated with tree size. Of all the trees with bark damage, 22% of the P. pinaster and 14% of the P. radiata had more than half of the stem circumference stripped. A number of these will probably suffer both stem distortion and growth retardation, and some may die.Methods of reducing the incidence of bark damage are discussed. 相似文献
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Manuel R. Guariguata Juan Carlos Licona Bonifacio Mostacedo Peter Cronkleton 《Forest Ecology and Management》2009
The success of multiple forest management systems is contingent on a variety of social, economic, biophysical, and institutional factors, including the integration of timber and non-timber forest product (NTFP) extraction and management. Selective logging for timber is increasingly taking place in forests where the collection of Brazil nuts, a high-value Amazonian NTFP, also occurs. We report on logging damage to Brazil nut trees in three certified timber concessions in Northern Bolivia from which timber is harvested using reduced-impact logging (RIL) guidelines and nuts are gathered yearly from the ground by local people. Observed frequencies of logging damage to Brazil nut trees were low, likely mirroring the low intensity of timber harvesting (∼0.5 trees/ha and ∼5 m3/ha) being currently applied across the study area. Of the trees ≥10 cm in diameter at breast height about 0.1 Brazil nut trees and 0.4 timber species per hectare suffered some degree of logging damage. Crown loss was the predominant damage type for Brazil nut trees accounting for 50% of all damage. In spite of the observed low rates of tree damage, we further recommend that RIL guidelines be amended to include the pre-harvest marking of pre-reproductive Brazil nut trees along with the future crop trees of commercial timber species. Further refining directional felling to reduce crown damage to Brazil nut trees would also serve to help maintain nut yields in the long term. 相似文献
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Tio Nevenimo John Moxon John Wemin Mark Johnston Colin Bunt R. R. B. Leakey 《Agroforestry Systems》2007,69(2):117-134
Canarium indicum is an indigenous tree of the lowland forests of Melanesia (Papua New Guinea, Solomon Islands, Vanuatu) and parts of Indonesia
producing edible nuts, commercial timber and some minor products. For thousands of years the nuts have been culturally important
and a traditional food. Since the early 1990s there have been a number of projects aimed at the wider commercialization of
the species, with mixed success. This review evaluates the biophysical and socio-economic literature and suggests how the
domestication and commercialization processes could be taken forwards to improve the livelihoods of rural households in Melanesia.
Many of the issues facing the domestication and commercialization of C. indicum nuts as an Agroforestry Tree Product (AFTP) are similar to those that will be important for the development of other AFTPs.
Thus there are lessons that can be learnt from this species which make it a model for other agroforestry tree species. 相似文献