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先树森:一起推车的人
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作者 曲瑾 《软件世界》 2003年第2期50-51,共2页
作为铂金中国有限公司的创始人之一,现任公司董事长,先树森先生负责管理公司在祖国大陆的所有业务,领导公司市场销售、业务开拓、咨询服务、技术支持以及产品开发和本地化业务。他从事企业管理应用系统领域已有二十多年,在管理软件系统... 作为铂金中国有限公司的创始人之一,现任公司董事长,先树森先生负责管理公司在祖国大陆的所有业务,领导公司市场销售、业务开拓、咨询服务、技术支持以及产品开发和本地化业务。他从事企业管理应用系统领域已有二十多年,在管理软件系统的产品战略、开发以及相关系统咨询方面拥有丰富的经验。 展开更多
关键词 铂金公司 软件产业 WTO 人力资源软件 市场需求 树森
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Dynamics of profiles and storage of carbon dioxide in broadleaved/Korean forest in Changbai Mountain 被引量:2
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作者 韩士杰 林丽莎 +4 位作者 于贵瑞 张军辉 吴家兵 赵晓松 关德新 《Journal of Forestry Research》 SCIE CAS CSCD 2003年第4期275-279,共5页
CO2 concentrations at different heights in a broadleaved/Korean forest (with a mean height of 26 m) were measured with infrared gas analyzer IRGA (model 2250D, LI-COR Inc. and LI-COR, 820) from Aug. to Oct. of 1999, A... CO2 concentrations at different heights in a broadleaved/Korean forest (with a mean height of 26 m) were measured with infrared gas analyzer IRGA (model 2250D, LI-COR Inc. and LI-COR, 820) from Aug. to Oct. of 1999, Apr. to Jul. of 2000, and from Aug. 2002 to Sept. 2003. Based on the collected dada, the diurnal and seasonal dynamics of profiles and storage of carbon dioxide in the forest were analyzed. The diurnal CO2 profiles showed that the vertical distribution of CO2 concentration were different for daytime and nighttime, and the CO2 concentration was highest close to forest floor, no matter at daytime and nighttime. The seasonal profiles of CO2 showed that stratification in the canopy was evident during growth season. CO2 concentrations at different heights (60 m to 2.5 m) had a little change in March, with a difference of 10 mmolmol-1, but had a significant change in July, with a difference of 60 mmolmol-1. In July, there also existed a greater gradient of CO2 concentrations at canopy (22, 26 and 32 m), with a difference of 8 mmolmol-1. The calculated total storage (ΔC/Δt ) of CO2 in the air column with height of 40 m beneath eddy covariance instrument was negative, and made a little contribution to NEE. 展开更多
关键词 CO2 concentration CO2 profile CO2 storage Broadleaved/Korean pine forest Vertical distribution Concentration gradient
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Acid Buffering Capacity of Forest Litter from Some ImportantPlantation and Natural Forests in South China 被引量:6
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作者 李志安 曹裕松 +2 位作者 邹碧 丁永祯 任海 《Acta Botanica Sinica》 CSCD 2003年第12期1398-1407,共10页
The role of forest litter as an acid-base buffering system was assessed by litter from plantation and natural forests in South China. Samples were either extracted with acid solutions or titrated with acid or base sol... The role of forest litter as an acid-base buffering system was assessed by litter from plantation and natural forests in South China. Samples were either extracted with acid solutions or titrated with acid or base solutions. Litter was found to be a strong acid-base buffering system. Two legume species, Acacia mangium Willd and A. auriculaiformis A. Cunn, had very high litter pH values of around 6, which was 2 pH units higher than that of the soil where they grew. Litter of all other plantation species had litter pH of around 4, similar to that of the soil. Both legume species have high potential to neutralize soil acidity and the litter layer could act to shield soil against acid rain. The current stand of two legume species was estimated to be able to raise rain acidity by 0.1 to 0.4 pH units. Inorganic ions did not fully explain the pH pattern of different litter extracts, but high sodium and low nitrate partly accounted for the high pH of the two legume species. Some natural forest species had extremely low pH. As a whole, the litter of the natural climax forest was the driving force of soil acidification. Although plant residues are strong acid-base buffering system and able to adjust acidity of environment, only a few species can be expected to make soil more acid or alkaline through this mechanism since most species have litter pH values similar to those of soil where they grow. 展开更多
关键词 acid-base buffer system inorganic ions acid rain forest litter legume species
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业界资讯
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《流程工业》 2003年第6期8-8,共1页
关键词 乳品产值 糖果工业 树森 夏明伟 瓦楞纸箱 包装机械 中国 轻工业
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风景园林树木病虫害防治分析
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作者 徐恋丽 《中文科技期刊数据库(全文版)工程技术》 2016年第12期217-217,共1页
文章先对风景园林树木病虫害防治方法进行了详细的研究,然后对于园林树木病虫害防治新技术进行了简要的阐述。
关键词 树森 病虫害 防治措施
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Changes in Soil Carbon Pools Induced by Substitution of Plantation for Native Forest 被引量:44
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作者 XUQIUFANG XUJIANMING 《Pedosphere》 SCIE CAS CSCD 2003年第3期271-278,共8页
Changes in soil carbon pools under Chinese fir (Cunninghamia lanceolata) andbamboo (Phyllostachys pubescens) plantations substituted for a native forest (Quercus acutissima,Cyclobalanopsis glauca, Cas-tanopsis sclerop... Changes in soil carbon pools under Chinese fir (Cunninghamia lanceolata) andbamboo (Phyllostachys pubescens) plantations substituted for a native forest (Quercus acutissima,Cyclobalanopsis glauca, Cas-tanopsis sclerophylla, Platycarya strobilacea, Lithocarpus glaber) werestudied on the hills with acid parent rock and soils classified as red soils (Ferrisols) in Huzhou,Zhejiang Province of east China. It was found that total soil organic carbon (TSOC), easilyoxidisable carbon (EOC) and water-soluble organic carbon (WSOC) under bamboo plantation wereincreased, but microbial biomass carbon (MBC) was decreased. On the contrary, Chinese fir induceddeclines of all fractions of C including TSOC, EOC, WSOC and MBC. The percentages of the activefractions of soil C (EOC and WSOC) were increased in the plantations as compared to the nativebroad-leaved forest, but proportions of soil organic C as MBC were decreased. It could be concludedthat bamboo plantation had a great ability of not only fixing C but also accelerating soil C poolcycle, improving nutrient and microorganism activity; therefore, it is a good ecosystem and could berecommended for wide development. Chinese fir would shrink the soil C pool and deteriorate soilbiological fertility, so it did not benefit CO2 fixing and land sustainable utilization. 展开更多
关键词 BAMBOO broad-leaved forest chinese fir soil carbon
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Effect of water extracts of larch on growth of Manchurian walnut seedlings 被引量:9
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作者 YANG Li-xue 《Journal of Forestry Research》 SCIE CAS CSCD 2005年第4期285-288,共4页
A study was conducted to detect the effect of water extracts from different parts such as root, bark, branch and leaf, of adult larch, Larix gmelini, trees on growth of Manchurian walnut, Juglans mandshudca, seedlings... A study was conducted to detect the effect of water extracts from different parts such as root, bark, branch and leaf, of adult larch, Larix gmelini, trees on growth of Manchurian walnut, Juglans mandshudca, seedlings and the allelopathy between the two tree species. Four concentrations (100 g. kg i, 50 g. kg^-1, 25 g. kg^-1 and 12.5 g. kg^-1) were prepared for each kind of extracts. Result showed that the water extracts with low and moderate concentrations accelerated the growth of collar diameter and increased biomass and root/shoot ratio of walnut seedlings. The water extracts from branches and barks with low and moderate concentrations accelerated the height growth of the seedlings, while those from leaves and roots slightly decreased the height growth of seedlings. The fact that application of water extracts of larch improved the growth of Manchurian walnut attributes possibly to the allelopathy between the two tree species. 展开更多
关键词 Juglans mandshurica Larix gmelini Water extract Collar diameter Tree height Root/shoot ratio ALLELOPATHY
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Fire temperature and residence time during dry season burning in a Sudanian savanna-woodland of West Africa with implication for seed germination 被引量:2
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作者 Sidzabda Djibril Dayamba Patrice Savadogo +3 位作者 Didier Zida Louis Sawadogo Daniel Tiveau Per Christer Oden 《Journal of Forestry Research》 SCIE CAS CSCD 2010年第4期445-450,522,523,共8页
Prescribed fire is used in the Sudanian savanna-woodland of West Africa as a forest management tool. An experiment was carried out to assess the effects of season of burning, and different vertical probe positions on ... Prescribed fire is used in the Sudanian savanna-woodland of West Africa as a forest management tool. An experiment was carried out to assess the effects of season of burning, and different vertical probe positions on maximum fire temperature and temperature residence time above 60℃ which is considered lethal for plant tissues. Seasons of burning considered were: an early season fire set at the beginning of the dry season (beginning of December), mid-season fire set at the peak of the dry season (mid-January), and a late season fire at the end of the dry season (end of March). The effects of these fires on the germination of buried seeds of three socio-economically valuable tree species were also examined. Results indicated significant differences in maximum fire temperature and residence time with respect to season of burning and vertical probe position (p 〈 0.001). The highest and longest lasting temperatures were observed at 20 cm above ground during early fire and at the soil surface during mid-season and late fires. This, in turn, affected germination responses of seeds buried at different soil depths. Implications of these findings in the current management practices are discussed. 展开更多
关键词 Burkina Faso fire season regeneration Savanna-woodland tropical ecosystem
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Temperature dependence of nitrogen mineralization and microbial status in O_H horizon of a temperate forest ecosystem 被引量:2
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作者 Ali Bagherzadeh Rainer Brumme Friedrich Beese 《Journal of Forestry Research》 SCIE CAS CSCD 2008年第1期37-43,共7页
It was hypothesized that increasing air and/or soil temperature would increase rates of microbial processes including litter decomposition and net N mineralization, resulting in greater sequestration of carbon and nit... It was hypothesized that increasing air and/or soil temperature would increase rates of microbial processes including litter decomposition and net N mineralization, resulting in greater sequestration of carbon and nitrogen in humus, and consequently development in OH horizon (humus horizon). To quantify the effect of temperature on biochemical processes controlling the rate of OH layer development three adjacent forest floors under beech, Norway spruce and mixed species stands were investigated at Soiling forest, Germany by an incubation experiment of OH layer for three months. Comparing the fitted curves for temperature sensitivity of OH layers in relation to net N mineralization revealed positive correlation across all sites. For the whole data set of all stands, a Q10 (temperature sensitivity index) value of 2.35-2.44 dependent on the measured units was found to be adequate for describing the temperature dependency of net N mineralization at experimental site. Species-specific differences of substrate quality did not result in changes in biochemical properties of OH horizon of the forest floors. Temperature elevation increased net N mineralization without significant changes in microbial status in the range of I to 15℃. A low Cmic /Corg (microbial carbon/organic carbon) ratio at 20℃ indicated that the resource availability for decomposers has been restricted as reflected in significant decrease of microbial biomass. 展开更多
关键词 BEECH SPRUCE nitrogen mineralization forest floor TEMPERATURE temperature sensitivity index (Q10)
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Enrichment planting in a logged-over tropical mixed deciduous forest of Laos 被引量:3
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作者 Sovu Mulualem Tigabu +2 位作者 Patrice Savadogo Per Christer Odén Lamphoune Xayvongsa 《Journal of Forestry Research》 SCIE CAS CSCD 2010年第3期273-280,395,396,共10页
Enrichment planting is commonly used for increasing the density of desired tree species in secondary forests often characterized by a prevalence of low commercial species. The objectives of the study were to identify ... Enrichment planting is commonly used for increasing the density of desired tree species in secondary forests often characterized by a prevalence of low commercial species. The objectives of the study were to identify the optimal enrichment planting method vis-à-vis gap and line planting, and to evaluate the performance of two dipterocarps (Vatica cinerea and Dipterocarpus alatus) and three legumes (Afzelia xylocarpa, Pterocarpus macrocarpus, Dalbergia cochinchinensis) planted in logged-over mixed deciduous forest of Laos. The enrichment planting trial was arranged in a randomized complete block design with seven replica-tions. Survival, height and diameter were measured seven years after planting and subjected to analysis of variance. Survival rate of planted seedlings did not vary between enrichment planting (p 0.05). However, diameter and height growth was favored more in gaps than in planting lines. This was related to rapid canopy closure in both gaps and lines, albeit more remarkable in planting lines. Significant inter-species varia-tion was detected for survival rate, height and diameter. The shade-tolerant dipterocarps had better survival and growth than the light-demanding leguminous species (p 0.0001). The size class distribution of individuals was irregular, accentuating uneven light condition in the understory. Given the difficulty to maintain constant line width and even light condi-tion, the cost of annual clean operation and the rigid geometric patterns of planting lines, the use of logged-over gaps for enrichment planting is recommended. Dipterocarpus alatus and V. cinerea are recommended for enrichment planting in mixed deciduous forests. A. xylocarpa, D. cochi-chinensis and P. macrocarpus can be planted in wider gaps, lines and open sites as plantation of mixed species or under canopy of young swidden forests. 展开更多
关键词 Gap planting Line planting Secondary forest Species trial Tropical forest
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Litter Dynamics of Three Subalpine Forests in Western Sichuan 被引量:83
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作者 YANG Wan-Qin WANG Kai-Yun +1 位作者 S. KELLOMAKI GONG He-De 《Pedosphere》 SCIE CAS CSCD 2005年第5期653-659,共7页
Litter production, components and dynamics were investigated and forest floor litter was quantified throughout awhole year in three subalpine forests, dominated by tree species of spruce (SF), fir (FF) and birch (BF),... Litter production, components and dynamics were investigated and forest floor litter was quantified throughout awhole year in three subalpine forests, dominated by tree species of spruce (SF), fir (FF) and birch (BF), in WesternSichuan, China, in order to understand the key factors that influenced litter production and dynamics. Litterfall in thethree forests consisted mainly of leaves, woody litter, reproductive organs and moss. Contribution of leaf litter to thetotal litterfall was significantly (P < 0.05) greater than that of woody litter, reproductive organs or moss. Regardlessof the stands, litterfall exhibited a marked monthly variation with the maximum litterfall peaks occurring in October,with smaller peaks occurring in February for SF and FF, and May for BF. The analysis indicated that tree species,stand density, leaf area index (LAI), stand basal area and stand age were the key factors determining litter production.Meanwhile tree species and phenology controlled the litter dynamics, with wind and snow modifying the litter componentsand dynamics. 展开更多
关键词 litter dynamics litter stock litter production subalpine forests
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Effects of Climate Warming on Phenological Characteristics of Urban Forest in Shenyang City,China 被引量:3
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作者 HE Xingyuan XU Sheng +3 位作者 XU Wenduo CHEN Wei HUANG Yanqing WEN Hua 《Chinese Geographical Science》 SCIE CSCD 2016年第1期1-9,共9页
Change in plant phenology is one of the most sensitive ecological responses to climate warming. Little information is known about the effects of climate warming on phenology of urban tree species in the northern fores... Change in plant phenology is one of the most sensitive ecological responses to climate warming. Little information is known about the effects of climate warming on phenology of urban tree species in the northern forest of China. In this study, we investigated the phenological characteristics of the main tree species in the urban forest of Shengyang City in China and the correlation between phenology and atmospheric temperature from the discontinuous data during past 42 years over three time periods(from 1962 to 1965, 1977 to 1978, and 2000 to 2005). The results showed that the annual average temperature in Shenyang City showed an increasing trend and increased by 0.96℃ from 1962 to 2005 due to climate warming. The germination phenology of the urban trees was negatively correlated with the temperature in winter and early spring. The leafing phenology was mainly influenced by the temperature in spring before leafing. Influenced by climate warming, the germination, leafing, and flowering phenologies of this urban forest in 2005 were 14, 13, and 10 days earlier than those in 1962, respectively. We inferred that further warming in winter might prolong the growing season of urban trees in the northern forest of China. 展开更多
关键词 global climate change global warming plant phenology urban forest Shengyang City
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Forest structure of a maple old-growth stand: a case study on the Apennines mountains(Southern Italy) 被引量:2
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作者 Pasquale A.MARZILIANO Vittoria COLETTA +3 位作者 Angelo SCUDERI Clemente SCALISE Giuliano MENGUZZATO Fabio LOMBARDI 《Journal of Mountain Science》 SCIE CSCD 2017年第7期1329-1340,共12页
In Europe, very small forest areas can be considered to be old-growth, and they are mainly located in Eastern Europe. The typical structures of old growth forests infrequently occur in Mediterranean mountainous enviro... In Europe, very small forest areas can be considered to be old-growth, and they are mainly located in Eastern Europe. The typical structures of old growth forests infrequently occur in Mediterranean mountainous environments, since they have been affected by human activities for centuries. This study focused on a remote and almost pure Italian maple stand located in southern Italy, which has not been managed for long time due to its inaccessibility. The effects of natural evolution on the forest stand were evaluated through the analysis of the spatial and chronological structure and the regeneration patterns, then estimating the amounts and quality of deadwood occurrence. Across the whole stand, all the trees with DBH (diameter at breast height) larger than 50 cm (LLT, large living trees) were measured (DBH and height) and age was also determined through a dendrochronological approach. The diameters observed ranged between 50 and 145 cm with ages of 12o to ~5o years. The Latham index calculated for trees within the sample plot highlighted a multilayered canopy with a dominant layer of largeliving trees (age 〉 120 years). The size-class distribution of stems had a reverse-J shape, and basal area was 52 m2 ha-1. Deadwood was exclusively constituted by standing dead trees and CWD and its volume was on average 31 m3 ha-1. Pure Italian maple forests are generally rare in Europe, and it was unexpected to find a forest stand characterized by a so complex structure with old growth attributes. The study of complex forest stand, even if small, could give precious information on the forest evolution, clarifying also diverse auto-ecological traits of tree species that usually are not common in our forests. 展开更多
关键词 Mediterranean mountainous ecosystems Natural evolution Stand characteristics DEADWOOD Unmanaged forests
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The Current Status of World Protection for Mangrove Forest
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作者 张征云 苏智先 +1 位作者 张桥英 申爱英 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2003年第3期261-269,共9页
Mangrove forests occur extensively in the tropic areas rich in wildlife and other non forestry resources and provide a wide array of raw materials for livelihood and production processes and have been a major source o... Mangrove forests occur extensively in the tropic areas rich in wildlife and other non forestry resources and provide a wide array of raw materials for livelihood and production processes and have been a major source of income generation and subsistence for the local people. Exploitation of timber, fuel wood, poles, industrial raw material, and many other non wood products from the mangrove forests give rise to large scale economic activity and income generation. At present, mangrove forests are facing great peril. Reckless exploitation and swampland reclamation result in their gradual degradation. This article deals with the worlds mangrove forest resources and their benefit to people; describes the current status, points out the main causes of the destruction of these forests, presents proposals for protecting mangrove forests, and discusses international cooperation in protecting the world’s mangrove forests. 展开更多
关键词 world mangrove forest mangrove forest resources economic value PROTECTION
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Crown Fuel Characteristics and Carbon Emission from Japanese Red Pine Stands Burned by Crown Fire in Mt. Palgong, South Korea 被引量:1
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作者 Byungdoo LEE Myoung Soo WON +1 位作者 Yohan LEE Myung Bo LEE 《Journal of Mountain Science》 SCIE CSCD 2012年第5期656-664,共9页
Carbon emissions from forest fires are considered an important factor of ecosystem carbon balance and global climate change. Carbon emissions from Japanese red pine stands (Pinus densiflora S. et Z.) burned by crown... Carbon emissions from forest fires are considered an important factor of ecosystem carbon balance and global climate change. Carbon emissions from Japanese red pine stands (Pinus densiflora S. et Z.) burned by crown fire were estimated at Mt. Palgong in Daegu Metropolitan City, and crown fuel characteristics, including crown bulk density, crown base height, and fuel moisture content of Japanese red pine, were analyzed. Total biomass combusted was calculated by subtracting the biomass of burned stands from that of unburned stands exhibiting similar stand structures and site environments. Ten trees in the unburned area and five trees in the burned area were cut by using direct harvesting techniques to estimate crown layer biomass. All biomass sampled was oven-dried and weighed. The dry weight ratios of stems, branches, and needles were 7o%, 21%, and 9%, respectively. The available fuel load susceptible to combustion during the crown fire spread was equivalent to 55% of the crown layer biomass. The crown bulk density was 0.24 kg/m3 on average. The estimated amount of CO2 was 23,454 kg CO2/ha for the crown layer. These results will be useful for calculating the amount of CO2 emitted from forest fires and for developing a forest carbon model in P. densiflora forests. 展开更多
关键词 Biomass burning Crown fire Fuelcharacteristics Bulk density Pinus densiflora
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Agrobacterium-mediated genetic transformation of Camptotheca acuminata
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作者 王慧梅 祖元刚 《Journal of Forestry Research》 SCIE CAS CSCD 2007年第4期316-318,共3页
UGPase gene related with wood cellulose synthesis was transferred into C. acuminata using the method of Agrobacte- rium-mediated genetic transformation, and an efficient transformation system was developed for C. acum... UGPase gene related with wood cellulose synthesis was transferred into C. acuminata using the method of Agrobacte- rium-mediated genetic transformation, and an efficient transformation system was developed for C. acuminata on the basis of evaluations of several factors affecting Agrobacterium-mediated DNA transfer rate. The highest transformation rate was achieved when pre-cultttred leaf explants were infected with an Agrobacterium culture corresponding to OD600 (0.5) for 10 min, and cultured on explant regeneration medium for three days. The results of Southern hybridization showed that genomic DNA of the kanamycin-resistant shoots to an UGPase gene probe substantiated the integration of the transgene. Transformation efficiency (6%) was achieved under the optimized transformation procedure, This system should facilitate the introduction of important useful genes into C, acuminata. 展开更多
关键词 Genetic transformation Camptotheca acuminata UGpase gene
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Impact of Teak (Tectona grandis Linn.) Thinning Out and Peacock-plume [Paraserianthes falcataria L. (1. Nielsen)] Harvesting on Mineral Cycle, Pod Rot Incidence, Changing of Cocoa Yield, and Land Productivity in Indonesia
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作者 Aloysius Adi Prawoto 《Journal of Agricultural Science and Technology(A)》 2012年第4期438-448,共11页
In 2009, Indonesia was included in a group of the ten biggest countries emitting greenhouse gases, and forest sector contributes 85%. This forest exploitation should be stopped, and by this research the industrial woo... In 2009, Indonesia was included in a group of the ten biggest countries emitting greenhouse gases, and forest sector contributes 85%. This forest exploitation should be stopped, and by this research the industrial wood species with special planting pattern was used as cocoa shade trees. The experiment was conducted in East Java, Indonesia, altitude 45 m above sea level using four planting patterns, i.e. (A) cocoa-Tectona grandis Linn. 3 m x 6 m, (B) cocoa-T, grandis 6 m x 4.2 m ~ 4.2 m (triangle), (C) cocoa-Paraserianthesfalcataria L. (I. Nielsen) 3 m ~ 6 m, and (D) cocoa-Leucaena sp. 3 m ~ 6 m (control). Cocoa was planted in 3 m ~ 3 m distance; between rows of teak and Paraserianthes was planted. Cassia surithensis of 3 m distance in the row, as reserve shade trees. At 6 year old, Paraserianthes was harvested, and at 7 year old, teak trees were thinned out 50% population for A and 66.7% for B treatments. The result showed that cocoa agroforestry by using timber trees in regular planting pattern and accurate spacing did not decrease cocoa yield but improved land productivity. Paraserianthes harvesting produced 0.71 m3 timber and the price was US$38.0-US $40.0 per tree, while teak thinning out produced 0.07 m3 wood per tree and it cost was US$5 per tree. From 108 Paraserianthes trees harvested, 81 cocoa trees were affected, 11.9% were seriously damage, 6.85% were medium damage, and 5.36% were light damage. On the other hand, teak spacing did not cause serious damage on cocoa trees. Biomass of harvested Paraserianthes and teak supplied back to soil 543 g and 250 g per tree respectively for equalities to total urea, SP 36, KC1, Kieserite and Dolomite. Paraserianthes harvest and teak thinning out made microclimate to be warmer, humidity to be lower, so pod rot incidence become lower and pod yield was improved, namely 71% and 27.25% for Paraserianthes plot and teak plot, respectively. Harvesting of Paraserianthes produced benefit/cost plot of 43.63, and teak thinning out of 3.60. The revenue obtained from timber sales easily offset the costs of damage of the cocoa crop. It is concluded that by using accurate planting pattern, cocoa area could produce industrial timber without sacrifying cocoa production and exactly improve land productivity. 展开更多
关键词 Cocoa timber shade trees thinning out pod rot mineral cycle YIELD land productivity benefit/cost.
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Primary Host Tree Species of the Gypsy Moth Lymantria dispar (Lepidoptera: Lymantriidae)in Hyrcanian Forests
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作者 G. Hajizadeh M. Reza-Kavosi 《Journal of Agricultural Science and Technology(B)》 2011年第3期342-346,共5页
Invasions by exotic insects and diseases are one of the most important threats to the stability and productivity of forest ecosystems around the world. Lymantria dispar (Lepidoptera: Lymantriidae) in Iran was obser... Invasions by exotic insects and diseases are one of the most important threats to the stability and productivity of forest ecosystems around the world. Lymantria dispar (Lepidoptera: Lymantriidae) in Iran was observed for the first time in 1937 by Jalal Afshar in oak forests of the Guilan state region. Since its introduction, gypsy moth has spread to the northern, western and south-western regions of Iran. The largest outbreaks of gypsy moth occurred in the Talesh Oak forests of the Hyrcanian zone in 1975. The gypsy moth is a highly polyphagous folivore species that feeds on over 300 species of woody plants. Among its most preferred hosts are oaks and aspens. Some trees are resistant to the gypsy moth including honey locust, black locust, silver maple, green ash, dogwood, sycamore, horse chestnut, firs, and tulip trees. Defoliation during severe outbreaks alters the appearance of forest habitats and leads to tree mortality and changes in stand composition. This study was conducted during 2008 and 2009 in an effort to determine the primary host tree species that the gypsy moth infests in the Hyrcanian forests of lran. For that purpose all egg masses in the area were counted and conclusively significant differences in defoliation levels among tree species were found. The primary host tree species of gypsy moth in Iran was Persian ironweed, Parrotia persica. 展开更多
关键词 Gypsy moth Lymantria dispar host tree species Parrotia persica persian ironweed hyrcanian forests.
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How do soil fauna and soil microbiota respond to beech forest growth?
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作者 Matthieu CHAUVAT Andrei S.ZAITSEV +1 位作者 Ernst GABRIEL Volkmar WOLTERS 《Current Zoology》 SCIE CAS CSCD 北大核心 2009年第4期272-278,共7页
The dynamics and performance of soil biota during forest rotation were studied in monoculture beech stands forming a chronosequence of four different age-classes(30,62,111,153 yr).Biomass was monitored in major groups... The dynamics and performance of soil biota during forest rotation were studied in monoculture beech stands forming a chronosequence of four different age-classes(30,62,111,153 yr).Biomass was monitored in major groups of microflora,microfauna,mesofauna,and macrofauna.Resource availability(litter layer,soil organic mater),biomass of the two dominant decomposer groups(microflora,earthworms)as well as the biomass of mesofauna and microfauna were found to remain quite stable during forest succession.Nevertheless,the marked increase of the biomasses of primary decomposers(fungi,saprophagous macroinvertebrates)in the 62-year-old stand,followed by an increase of the biomasses of macropredators in the 111-year-old stand,indicate substantial changes of several components of edaphic communities during forest development.However,constant values of soil respiration suggest that the overall performance of the soil food web does not change during beech forest succession.Thus,the decomposer system of lowland managed beech forests on calcareous soils seems to be very stable over time.We suggest that earthworm activity might have masked impacts of forest development on other soil biota and led to an astounding stability of decomposer assemblages during beech forest rotation. 展开更多
关键词 BEECH CHRONOSEQUENCE Ecosystem performance Soil food-web Forest
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Low net primary productivity of dominant tree species in a karst forest, southwestern China: first evidences from tree ring width and girth increment 被引量:1
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作者 Jian Ni Haiyang Xu Libin Liu 《Acta Geochimica》 EI CAS CSCD 2017年第3期482-485,共4页
Aboveground net primary productivity(ANPP)of two dominant species, one deciduous tree(Platycarya strobilacea) and one evergreen tree(Machilus cavaleriei),was estimated based on the tree-ring width and the girth increm... Aboveground net primary productivity(ANPP)of two dominant species, one deciduous tree(Platycarya strobilacea) and one evergreen tree(Machilus cavaleriei),was estimated based on the tree-ring width and the girth increment as well as allometric functions in a karst evergreen and deciduous broadleaved mixed forest in central Guizhou Province, southwestern China. Results showed that the ANPP increased from 1961 to 2015, especially during the last 20–30 years, but with strong variations. The deciduous tree had higher ANPP than the evergreen tree according to two kinds of estimates by the tree ring and girth increment. The averaged ANPP for these two mature trees was 2.27 kg/individual/year, ca. 8 t/ha/year considering the normal stand density. Such karst forest productivity was lower than the natural subtropical forests in China and in the world. 展开更多
关键词 Biomass increment Tree ring Girth measurement Karst evergreen and deciduous broadleaved forest Allometric functions
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