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Zhou Hongze Ye Ronghua Northeast Forestry University 《林业研究》1991,2(2):89-94
After forest fire,It is very needd to locate fire position and assess the loss of forestresources.In this paper,a method of burned forest assessment with satellite remote sensing dataand over-laying techniques is discussed and used in the assessment of the burned forest in Malinforest Farm after the large forest fire of May,1987. 相似文献
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Asemini is a Northern Hemisphere cerambycid tribe,and an important forest pest, mainly causing damage to coniferous plants.More important,as one kind of quarantine insects,Asemini can bring about many troubles in timber trade, therefore,the alien species should be paid more attentions and need to be quarantined in order to prevent them to be introduced to China.In China, there are 4 genus 26 species of Asemini.Host plants of Asemini include 15 genus 36 species of 7 families, and the main host plants are in Pinus,accounting for 30.56%of the total.A fauna analysis indicated that 15 species of Asemini distributed in the Palareartic Realm,accounting for 57.69%of the total. The species predominated in China,probably because gymnosperms were the main vegetable type in this region.This paper lists all the known species and genera of Asemini and their host plants in China,and discusses their distribution.The aim is to arouse the concerns of these insects and provide a reference for the relevant work. 相似文献
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WANGXian-cheng 《林业研究》2003,14(3):259-262
Changbai Mountain forest area is not only is a national timber base but also a green ecological defense for Songliao Plain of NE China. The Natural Forest Protection Project of this area has an important bearing on the social and economic sustainable development of Jilin Province or even the whole forest area in NE China. This paper summarized general conditions of natural forest in Changbai Mountain state-owned forest area and put forward six problems need to be urgently solved and five strategic suggestions on natural forest protection and sustainable management. 相似文献
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CHEN Jie Research Institute of Forestry Policy Information Chinese Academy of Forestry Beijing P.R.China 《中国林业科技(英文版)》2007,6(3):85-92
Though public forests in countries take up a small portion of forests, their importance in respect of environmental side looms large gradually. This paper studies and compares the public forest management and forest laws in France and the USA, attempting to explore the forest operation practice in both countries and the emphasis of the law governing forest management, so that a lesson can be drawn for us to learn in China. 相似文献
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LiuJunchang HuMingxing 《中国林学(英文版)》2004,6(1):42-47
Based on the current conditions, a forecast of trends in imports and exports of wood products and their demand and supply is presented in this paper for the years of 2005 and 2015. It is expected that imports will continue to exceed exports but that the trade deficit in wood products will decline. The form of trade will be changed from a condition of unilateral imports to one of exerting mutual advantage through imports and exports. The structure of trade in forest products will alter with changes in the forest resource base and with new developments in the forest industry. 相似文献
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Forest Resources and Environment in China 总被引：1，自引：0，他引：1
FAN Shaohui ZENG Xiangwei ZHANG Qun Science Research Division International Center For Bamboo RattanChinese Academy of Forestry International Department Chinese Society of Forestry Forest Research Institute Chinese Academv of Forestry 《中国林业科技(英文版)》2004,3(4):88-95
With a vast territory, China is rich in forest resources and diversified environments. The changes in forest resources have a direct bearing on environmental quality. The paper gives a detailed account of the dynamic change in forest resources in China, including the overall process of forest evolution, the status quo and features of the existing forest resources and the development and use of major forest resources. In addition, it analyses the current situation of China's environment and explores the main contributing factors based on the overall environmental situation. In order to achieve sustainable management of forest resources and improve the environment in China, the Chinese government attaches great importance to the protection and development of forest resources as well as environmental development and improvement. The paper gives an overview of the thinking for sustainable forest resource and environmental development in the future and current focus of efforts. 相似文献
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ZHANG YingCollege of Economics Management Beijing Forestry University Beijing . P. R. China 《中国林业科技(英文版)》2003,(3)
According to the evaluative data of forest biodiversity variation in China from 1973 to 1998, not only the gray model GM( 1,2), but also the status spatial characterization model with the optimal control model for forest biodiversity variation is developed by using some mathematic approaches and knowledge in economic cybernetics. Furthermore, the structural characteristics of forest biodiversity variation are analyzed. The paper points out that the variation of forest biodiversity is instable, but it can be controlled and known certainly. The close-loop feedback controlling and the optimal controlling are also existent. That is to say, the preestablished targets of forest biodiversity variation can be met by adjusting the policy's variables, thus alleviating the pressure of forest biodiversity. The variation of forest biodiversity can be shown by the pressure index of variation. This paper finally shows that when the pressure index of forest biodiversity is a constant 100, the optimal movement curves ar 相似文献
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We investigated the floristic composition, woody species diversity and spatial distribution of trees in a tropical wet evergreen forest in Kaptai national park in Chittagong Hill Tracks, Bangladesh. We recorded 25 families, 37 genera, 40 species and 1771 woody individuals in a 0.09 ha plot. Euphorbiaceae and Moraceae were the most speciesrich families, and Castanopsis, Ficus and Terminalia were the most species-rich genera. Bursera serrata Wall. ex Colebr. was the dominant species in terms of highest importance value(13%). Trema orientalis(L.)Bl was typically a light demanding species as it appeared in the top canopy with only one individual having the seventh highest IV, but had no regeneration. The expected maximum number of species(Smax) was 140,indicating that many species may invade the forest as the Smax is greater than the recorded total number of species. The nature of the disappearance and appearance of species in the present forest reflects instability of floristic composition. The values of Shannon's index H ′ and Pielou's index J ′(evenness) were 3.36 bit and 0.63, respectively. These values show moderately high species diversity as compared to other subtropical forests in the tropics. In addition, a sample area of 200 m2 in this forest would be sufficient for measuring the diversity indices H ′ and J ′,whereas the trend of J ′may indicate the rate of equality of individuals among the different species decreased with increasing area. The distribution pattern for the total stand was completely random. However, the dominant species showed aggregate distribution for small areas, but random distribution for large areas. The spatial association between species showed that the strongest positive interspecific association occurred between Streblus asper Lour. and Castanea indica Roxb.(ω =0.51). As a whole, most species were weakly associated with each other,of which 58% species associations were completely negative. The result of cluster analysis showed that species pairs were spatially independent at all or most small clusters; stands of species from all clusters are mosaics of complete habitat and pioneer habitat. All patches in this forest community have similar habitat and regeneration niches, which could be a phenomenon for a young growth forest. Thus, the existence of habitat and regeneration niches may be an important factor in the maintenance of diversity in this forest. 相似文献
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The largest and most precious Chinese butterfly Troides helena spilotia Rothschild is occurring all year round with overlapping 6 generations in Hainan Jianfengling forest each year. The appropriate growth temperature for it is 25－30 ℃, and the humidity is 70%－80%. Large-scale artificial breeding of Troides helena spilotia Rothschild need to comply with the requirements of their breeding rooms by planting host plants for their eggs. Dilution of the concentration of honey and water is 10%－15% in summer and 5% in winter; the eggs should be moisturizing when collecting indoor and outdoor. The larvae should be transferred to the host plants planted in the field with net bags; and transfer them to different host plants timely according to their instars and food intake; the indoor population density should be controlled. Due to the 4－5 instars larvae will ingest a great deal of food, they need to be fed 3 times a day in the morning, afternoon and the evening. The ways to suspend the pupa when feeding indoor and outdoor vary according to the breeding facilities. The pupa should be collected and put in the emergence room and hung them up according to their natural shape. The suitable temperature for it is 25－28 ℃, and humidity is 60%－80%. 相似文献
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《中国林业科技(英文版)》2010,(2):50-55
Man-made forest, which is the forest ecosystem of rehabilitation and reconstruction, plays a significant role in the provision of forest products and improvement the ecological environment. In this paper, we established the AR (5) model to predict China's forest area from 2009 to 2015. This study shows the slow growth of the national plantation area trend with some fluctuations, but the overall growth rate is not large. We proposed that on one hand China should continue to increase the plantation area, on t... 相似文献
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影响角倍产量的主导气象因子研究 总被引：1，自引：0，他引：1
本文采用逐步回归法对角倍产量与它前期气象因子的关系作了主导气象因子的筛选,指出影响角倍产量的主要时期及主导气象因子是越冬若蚜速生期的极端气温;翅蚜出现期的平均气温;性蚜生育期的降雨量或湿度;干母生育期的平均气温。本文还提出,用主导气象因子建立的回归模式建行角倍产量预报和产地气候区划的可能性。 相似文献
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鉴定确认：竹山县五倍子蚜冬寄主7种；某中肚倍蚜冬寄主4种；红小铁枣蚜、倍花蚜及周氏倍花蚜冬寄主各1种。 相似文献
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本文主要对倍林资源现状、五倍子生产经营水平、技术开发潜力及五峰县实现年产60 0 0t五倍子产业化发展目标的对策进行了论述 相似文献
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