共查询到20条相似文献,搜索用时 31 毫秒
1.
Jiying Song Youqing Luo Juan Shi Xiaosu Yan Weiping Chen Ping Jiang 《Frontiers of Forestry in China》2006,1(4):460-463
In November 2003 and June 2004, the insect borers and their spatial distribution within Pinus massoniana were investigated in Zhoushan City, in East China’s Zhejiang Province, where pine wood nematode (Bursaphelenchus xylophilus) are typically found. The niche width, proportional similarity of niche and the niche overlap of dominant species of dying
trees were computed. Results show that five insect species infect and damage Pinus massoniana, which had been infected by pine wood nematodes, among which four are wood boring beetles and one termite. Species within
host trees vary from winter to summer and all the species have their own niche width, proportional similarity of niche and
the niche overlap. They can achieve competitive equilibrium and coexistence according to their biological characteristics
and life habits.
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Translated from Journal of Beijing Forestry University, 2005, 27(6): 108–111 [译自: 北京林业大学学报, 2005, 27(6): 108–111] 相似文献
2.
Haijun Liu Youqing Luo Junbao Wen Zhiming Zhang Jihua Feng Wanqiang Tao 《Frontiers of Forestry in China》2006,1(3):328-335
According to the international methods of pest risk analysis and urban forestry characteristics in Beijing, a quantitative
risk assessment system in Beijing for three primary non-indigenous pests was proposed. This system was used to analyze three
major non-indigenous species, Dendroctonus valens, Hyphantria cunea, and Apriona swainsoni. The results show that the risks of these three pests in the Beijing area were 2.46, 2.30, and 2.02, which were all highly
risky. Based on the result and extensive risk communications, combined with the management experience of the Beijing Forest
Protection Station, the authors proposed some effective control measures to prevent the invasion of the three pests into Beijing.
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Translated from Journal of Beijing Forestry University, 2005, 27(2): 81–87 [译自: 北京林业大学学报, 2005, 27(2): 81–87] 相似文献
3.
Lili Zhang Zhenyu Li Hailin Li Ruidong Han Yongli Zhao 《Frontiers of Forestry in China》2006,1(4):453-459
Chinese pine caterpillar (Dendrolimus tabulaeformis) larvae were fed with pine needles of different degrees of damage to evaluate the effects of pine needles on the growth and
development of larvae. The results showed that the nutritional index of the larvae declines after feeding on the damaged pine
needlings. The lowest amount of food ingested and voided feces, the lowest nutritional index, slowest development, lightest
pupae and most mortality were found in those pine caterpillar larvae fed with pine needles which were 50% damaged. The damaged
pine needles significantly affected the population dynamics of Chinese pine caterpillars. The nutritional indices of larvae
fed with 25% and 75% damaged pine needles were similar. The nutritional index of the dark morphs was higher than that of the
tinted morphs, however, their mortality was lower than that of the tinted morphs. This phenomenon was reversed at the later
stage of development when the larvae were fed on 50% damaged pine needles.
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Translated from Journal of Beijing Forestry University, 2005, 27(6): 83–88 [译自: 北京林业大学学报, 2005, 27(6): 83–88] 相似文献
4.
This paper studied root biomass and underground carbon (C) and nitrogen (N) storage of a more than 200-year-old primitive
Korean pine and broad-leaved forest and its two 20-and 80-year-old secondary Populus davidiana and Betula platyphylla forests in Changbai Mountain, northeast China. The results showed that with forest succession, the root biomass of 20-year-old,
80-year-old, and primitive forests was 2.437, 2.742, and 4.114 kg/m2, respectively. The root C storage was 1.113, 1.323, and 2.023 kg/m2, soil C storage was 11.911, 11.943, and 12.587 kg/m2, and underground C storage was 13.024, 13.266, and 14.610 kg/m2, respectively, while the root N storage was 0.035, 0.032, and 0.038 kg/m2, soil N storage was 1.208, 1.222, and 0.915 kg/m2, and underground N storage was 1.243, 1.254, and 0.955 kg/m2, respectively, which indicated that along with forest succession, the forest underground became a potential “carbon sink,”
whereas underground N storage did not change obviously.
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Translated from Chinese Journal of Applied Ecology, 2005, 16(7): 1,195–1,199 [译自: 应用生态学报, 2005, 16(7): 1,195–1,199] 相似文献
5.
The interactions between pine wood nematode and three bacterium strains isolated from the nematode, Bursaphelenchus xylophilus, which are two strong pathogenic bacterium strains, Pseudomonas fluorescens GcM5-1A and Pseudomonas putida ZpB1-2A and a weak-pathogenic bacterium strain, Pantoea sp. ZM2C, were studied. The result showed that the strong-pathogenic GcM5-1A strain and ZpB1-2A strain significantly increased
fecundity, reproduction rate, and the body volume of the adult nematode. Meanwhile, pine wood nematodes significantly promoted
reproduction of the two strong-pathogenic bacterium strains. However, the weak-pathogenic bacterium strain, ZM2C, completely
inhibited reproduction of pine wood nematodes. Aseptic pine wood nematodes significantly inhibited reproduction of the strain
ZM2C. The results indicated that mutualistic symbiosis exists between pine wood nematodes and the two pathogenic bacteria
it carries. The phenomenon showed that the pathogenic bacteria carried by the nematode were not accidentally contaminated,
but rather had existed as symbionts of the nematode with which it had coevoluted over a long period. The role of mutualistic
symbiosis in the process of pine wilt disease was also discussed.
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Translated from Journal of Nanjing Forestry University, 2005, 29(3): 1–4 [译自: 南京林业大学学报, 2005, 29(3): 1–4] 相似文献
6.
Zhende Yang Boguang Zhao Lin Zhu Jie Fang Luqing Xia 《Frontiers of Forestry in China》2006,1(2):190-195
Alkaloids from Sophora alopecuroids were bioassayed with Clostera anastomosis for their antifeedant and growth inhibitory effects. The antifeedant rate in choice test reached 62%–86% at the dose 2.5
mg/mL, while in non-choice bioassay the rate was only 20%–29%. In choice bioassay, the antifeedant rate increased with larval
instars of C. anastomosis and did not in non-choice experiment. The alkaloids also imposed a strong influence on the growth of C. anastomosis larvae, i.e., after feeding on the leaves treated with alkaloid, the larvae lost their weight, weight gain, and relative
growth rate (RGR) significantly when compared with the controls. In the second day after treatment with the dose at 10 mg/mL
of the alkaloid, the RGR reduced by 39.8%, and the food intake and the feces weight were respectively 57.7% and 57.4% of the
controls. The approximate digestibility (AD) increased significantly, and the efficiency in converting digested food (ECD),
and the efficiency in converting ingested food (ECI) decreased greatly after feeding the treated leaves. Moreover, the eggs
laid per female were also inhibited by this alkaloid. The significance and prospect of the alkaloids in controlling forest
insect pests were also discussed.
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Translated from Scientia Silvae Sinicae, 2005, 41(4) [译自: 林业科学, 2005, 41(4)] 相似文献
7.
Hepatacodium miconioides is the Class II protected plant species in China. This paper studies the genetic diversity and differentiation of its nine
natural populations in Zhejiang Province by using random amplified polymorphic DNA (RAPD) technique. Twelve random primers
were selected in the amplification, and 164 repetitive loci were produced. The percentage of polymorphic loci in each H. miconioides population ranged from 14.60% to 27.44%, with an average of 20.73%. Among the test populations, Kuochangshan had the highest
percentage of polymorphic loci, Simingshan took the second place, and Guanyinping had the lowest percentage. As estimated
by Shannon index, the genetic diversity within H. miconioides populations accounted for 27.28% of the total genetic diversity, while that among H. miconioides populations accounted for 72.72%. The genetic differentiation among H. miconioides populations as estimated by Nei index was 0.715,7. This figure was generally consistent with that estimated by Shannon index,
i.e., the genetic differentiation among populations was relatively high, but that within populations was relatively low. The
gene flow among H. miconioides populations was relatively low (0.198,7), and the genetic similarity ranged from 0.655,7 to 0.811,9, with an average of 0.730,6.
The highest genetic distance among populations was 0.422,9, while the lowest was 0.208,3. All the results showed that there
was a distinct genetic differentiation among H. miconioides populations. The genetic distance matrix of nine test populations was calculated using this method, and the clustering analysis
was made using the unweighted pair group method with arithmetic mean (UPGMA). The cluster analysis suggested that the nine
populations of H. miconioides in Zhejiang Province could be divided into two groups, the eastern Zhejiang group and the western Zhejiang group.
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Translated from Chinese Journal of Applied Ecology, 2005, 16(5): 795–800 [译自: 应用生态学报, 2005, 16(5): 795–800] 相似文献
8.
The regeneration of exhausted solutions of electroless nickel plating wood veneer was realized using soluble calcium salt
to precipitate and remove phosphite and then using fluoride to remove residual calcium ions from the solution. The effect
of the pH value of the solution, treatment temperature and the molar ratio of calcium ions to phosphite ions on the removal
efficiency of phosphite was investigated. Wood veneer was electroless plated using regenerated solutions. A coating with better
electrical conductivity and electromagnetic shielding was obtained.
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Translated from Journal of Northeast Forestry University, 2005, 33(3): 47–48 [译自: 东北林业大学学报, 2005, 33(3): 47–48] 相似文献
9.
Correlations between canopy gaps and species diversity in broad-leaved and Korean pine mixed forests
Regeneration of tree species associated with canopy gaps in broad-leaved Korean pine forests was investigated. Species diversity
in gaps and under closed canopy was compared, the relationship between biodiversity and gap structure was analyzed. Results
indicate that there were significant differences between tree species diversity in gaps and that under canopy (p<0.01). In terms of Shannon-Wiener index, evenness index, and abundance index, the biodiversity in gap community were higher
than those under forest canopy in regeneration layer. In terms of Simpson’s dominance index, the dominance of certain species
in the regeneration layer increased from gaps to closed canopy (p<0.01). In contrast, trends of biodiversity changes of succession layer in gaps and under closed canopy were opposite. Tree
species diversity of different layers reacted directly to the change of gap size class. For example, Shannon-Wiener index
and abundance index is higher and Simpson’s dominance index is the lowest in succession layer of medium-size gap (100–250
m2) in the broad-leaved Korean pine forest of Changbai Mountains. Shannon-Wiener index reached the highest in a size of ≥250
m2 and <100 m2, reached the lowest in a size of 200–250 m2 in the regeneration layer. Simpson’s dominance index reached its maximum when the gap size was between 200 and 250 m2. Generally, species of different layers reacted differently to the changes of gap size classes. The gap size class with more
seedlings did not correspond to size class containing more medium-size trees. Tree species diversity indices in the two layers
behaved reciprocally during the development process of forest gaps.
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Translated from Chinese Journal of Applied Ecology, 2005, 16(12): 2,236–2,240 [译自: 应用生态学报, 2005, 16(12): 2,236–2,240] 相似文献
10.
Organic acid exudation from the roots of Cunninghamia lanceolata and Pinus massoniana seedlings under low phosphorus stress 总被引:1,自引:0,他引:1
Yuanchun Yu Jian Yu Qihua Shan Li Fang Defeng Jiang 《Frontiers of Forestry in China》2008,3(1):117-120
Organic acid exudation from the roots of Chinese fir (Cunninghamia lanceolata) and Masson pine (Pinus massoniana) seedlings under low phosphorus stress was studied using the solution culture method. The results revealed that organic acid
exudation from the roots of Chinese fir and Masson pine seedlings under low phosphorus stress increased. Compared with P3 (KH2PO4, 0.5 mmol/L), the average organic acid exudation from the root of Masson pine seedlings under P0 (KH2PO4, 0 mmol/L), P1 (KH2PO4, 0.03 mmol/L) and P2 (KH2PO4, 0.09 mmol/L) increased by 328.6%, 267.9% and 126.4% respectively. Masson pine from Zhejiang Province in China had the highest
organic acid exudation. Under low phosphorus stress, the increase in organic acid exudation from the different provinces of
Chinese fir and Masson pine varied. Masson pine from Zhejiang Province mainly increased oxalic acid, tartaric acid, citric
acid and malic acid exudation, that from Guangxi Province mainly increased oxalic acid and tartaric acid exudation, and that
from Guizhou Province, China mainly increased oxalic acid, tartaric acid and malic acid exudation. Chinese fir mainly increased
oxalic acid and tartaric acid exudation.
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Translated from Journal of Nanjing Forestry University, 2007, 31(2): 9–12 [译自: 南京林业大学学报] 相似文献
11.
Variations of fine root diameter with root order in Manchurian ash and Dahurian larch plantations 总被引:1,自引:0,他引:1
Xiangrong Wang Zhengquan Wang Youzhi Han Jiacun Gu Dali Guo Li Mei 《Frontiers of Forestry in China》2007,2(1):34-39
Fine root lifespan and turnover play an important role in carbon allocation and nutrient cycling in forest ecosystems. Fine
roots are typically defined as less than 1 or 2 mm in diameter. However, when categorizing roots by this diameter size, the
position of an individual root on the complex lateral branching pattern has often been ignored, and our knowledge about relationships
between branching order and root function thus remains limited. More recently, studies on root survivals found that longevity
was remarkably different in the same branching level due to diameter variations. The objectives of this study were: (1) To
examine variations of fine root diameter from the first-to fifth-orders in Fraxinus mandshurica Rupr and Larix gmelinii Rupr roots; and (2) To reveal how the season, soil nutrient, and water availability affect root diameter in different branch
order in two species. This study was conducted at Maoershan Forest Research Station (45°21′–45°25′N, 127°30′–127°34′E) owned
by Northeast Forestry University in Harbin, northeast China. Both F. mandshurica and L. gmelinii were planted in 1986. In each plantation, fine roots of two species by sampling up to five fine root branch orders three
times during the 2003 growing season from two soil depths (i.e., 0–10 and 10–20 cm) were obtained. The results showed that
average diameters of fine roots were significantly different among the five branch orders. The first-order had the thinner
roots and the fifth order had the thickest roots, the diameter increasing regularly with the ascending branch orders in both
species. If the diameter of fine roots was defined as being smaller than 0.5 mm, the first three orders of F. mandshurica roots and the first two orders of L. gmelinii roots would be included in the fine root population. The diameter ranges of the fine roots from first-order to fifth-order
were 0.15–0.58, 0.18–0.70, 0.26–1.05, 0.36–1.43, and 0.71–2.96 mm for F. mandshurica, and 0.17–0.76, 0.23–1.02, 0.26–1.10, 0.38–1.77, and 0.84–2.80 mm for L. gmelinii. The average coefficient of variation in first-order roots was less than 10%, second-and third-order was 10–20%, and fourth-and
fifth-order was 20–30%. Thus, variation in root diameter also increased with the ascending root order. These results suggest
that “fine roots”, which are traditionally defined as an arbitrary diameter class (i.e., <2 mm in diameter) may be too large
a size class when compared with the finest roots. The finest roots have much shorter lifespan than larger diameter roots;
however, the larger roots are still considered a component of the fine root system. Differences in the lifespan between root
diameter and root order affect estimates of root turnover. Therefore, based on this study, it has been concluded that both
diameter and branch order should be considered in the estimation of root lifespan and turnover.
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Translated from Acta Phytoecologica Sinica, 2005, 29(6): 871–877 [译自: 植物生态学报] 相似文献
12.
Qiang Liu Shaolin Peng Hua Bi Hongyi Zhang Zhi’an Li Wenhui Ma Niya Li 《Frontiers of Forestry in China》2006,1(3):243-252
In order to explore the release of nutrients and the effects of global warming on the decomposition rate of forest litter,
an experiment is designed to reciprocally decompose forest foliar litter in two sites across climatic zones: Mt. Jianfengling
in Hainan Province in the tropics and Mt. Dinghushan in Guangdong Province in the subtropics. The two sites have similar altitudes,
soil types, annual mean rainfall and seasonality of dry and wet. The main difference between these two sites is the annual
mean temperature with the difference of 3.7°C. Foliar litters of 10 native dominant tree species have been collected respectively
from the two sites and divided into single-species litter and mixed litter. They are decomposed reciprocally in the two sites.
The results indicate that litter decomposes in the tropical site 1.36–3.06 times more rapidly than in the subtropical site.
Apparent Q
10, calculated on the basis of the temperature difference between the two sites, ranges from 3.7 to 7.5. The return amount of
N, P and C will increase by 32.42, 1.033 and 741.1 kg/hm2, respectively in Mt. Dinghushan in the first year’s litter decomposition under the prevailing temperature condition. Only
in Mt. Dinghushan is the correlation between decomposition rate constant and initial litter quality high and significant in
the ratio of lignin to N, lignin, the ratio of lignin to P, HLQ and C. This is not the case at Mt. Jianfengling.
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Translated from Journal of Beijing Forestry University, 2005, 27(1): 24–32 [译自: 北京林业大学学报, 2005, 27(1): 24–32] 相似文献
13.
14.
For the first time during October 2006, the occurrence of Obolodiplosis robiniae (Haldeman 1847) (Diptera: Cecidomyiidae) was recorded on the black locust (Robinia pseudoacacia L.) in Slovakia. During 2007, field surveys were undertaken to determine the distribution of the species and the infestation
ratio at different locations. One year after its first discovery, O. robiniae was found throughout southern Slovakia. The gall midge was observed in 148 out of 161 checked locations. The infestation
ratio of single leaves varied from 4 to 100%. The infestation ratio of the black locust tree was evaluated during May–June,
July–August, and September–October, and accounted for 15–39, 9–53, and 6–49%, respectively. The most frequent infestation
ratio fluctuated from 10 to 30% (115 locations). The highest infestation was recorded during July–August. Greater infestation
was prevalent in the larger settlements than it was in the countryside. The gall midge was also recorded on R. viscosa Vent. Although the results show that O. robiniae is nowadays an usual insect with high potential to become an important pest of ornamental black locust or biological control
agent against weedy black locust in southern Slovakia, the species do not appear to have reached pest status until now. 相似文献
15.
The growth process of natural poplar-birch forests 总被引:1,自引:0,他引:1
With a combination of permanent and temporary sample plots, we investigated the growth conditions of natural poplar-birch
forests. The forests were divided into four site classes, using statistical and analytical techniques in a quantitative model,
in descending order where site class I was the best. On this basis, the growth of natural poplar-birch forests in the different
site classes was studied. The growth processes of height and diameter at breast height were divided into three stages: a fast
growing period, a stable growing period and a slow growing period. Results of this study provide a theoretical basis for the
directive cultivation of natural poplar-birch forests.
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Translated from Journal of Northwest Forestry University, 2005, 33(5): 9–12 [译自: 东北林业大学学报, 2005, 33(5): 9–12] 相似文献
16.
A comparison of genetic diversity and differentiation in five Chinese pines using cpSSR and AFLP markers 总被引:1,自引:0,他引:1
Gene diversity and genetic differentiation in five Chinese pines, Pinus henryi, P. tabulaeformis, P. yunnanensis, P. taiwanensis and P. massoniana, were compared using amplified fragment length polymorphism (AFLP) and simple chloroplast sequence repeat (cpSSR). High genetic
differentiation and median gene diversity with cpSSR markers were found both at population and species level, while median
differentiation and higher gene diversity in AFLP data. Measures of subdivision that consider similarity between haplotypes
offered better information on the geographic structure of plants than the standard subdivisions. Among several methods analyzed
in AFLPs, the square root method provided downwardly biased estimates of the genetic parameters, while the Lynch and Milligan
method over-estimated genetic diversity due to a small sample size. The Bayesian statistic was the most accurate and popular
method for these dominant species and its value of species differentiation (θ
B = 0.1035) was close to the parameter given by analysis of molecular variance (AMOVA).
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Translated from Acta Botanica Boreali-Occidentalia Sinica, 2007, 27(12): 2385–2392 [译自: 西北植物学报] 相似文献
17.
To enrich resource of species, 105 arbor species (25 genera, 15 families) were introduced to the hilly and gully areas on
Loess Plateau. By acclimation and selection, more than 90 tree species (12 genera, 8 families) were identified as fine species,
including trees suitable for sloping fields such as Pinus sylvestri var mongolica, Pinus tabulaeformis, Platycladus orientalis, and Robinia pseudoacacia, trees suitable for gully bottoms such as Populus davidiana, Populus diversifolia, and Salix cheilophila and non-timber trees such as Prunus armeniaca, Ziziphus jujuba and Prunus persica. For those fine trees, habitat conditions and regularity of requirement of water and fertilizers were studied and then habitat
ranges were given. From research results, it could be seen that Robinia pseudoacacia consumed more water, but it could improve the content of organic matters in soil; by contrast, Pinus tabulaeformis and Platycladus orientalis consumed less water and were suitable for dry sloping fields; species of apricot were suitable for sunny or semi-shady sloping
fields with good conditions of water and fertilizer; species of pear were suitable for both shady sloping fields and sunny
sloping fields; species of Chinese date were suitable for sunny sloping fields.
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Translated from Scientia Silvae Sinica, 2005, 41(5) [译自: 林业科学, 2005, 41(5)] 相似文献
18.
Haili Qiao Chengming Tian Youqing Luo Jianhua Sun Xiaofeng Feng 《Frontiers of Forestry in China》2008,3(3):347-351
To better understand the distribution of soil microorganisms in Populus euphratica forests in Xinjiang, northwestern China, we studied and compared the populations and numbers of bacteria, fungi and actinomycetes
in the soil at four different age stages of natural P. euphratica forests, i.e., juvenile forests, middle-aged forests, over-mature forests and degraded forests. Results showed that there
were clear differences in the amount of microorganism biomass and composition rates across the four forest stages. Dominant
and special microorganisms were present in each of the four different soil layers. The vertical distribution showed that the
microorganism biomass decreased with increasing soil depth. The population of microorganisms was the lowest at 31–40 cm of
soil depth. The microorganisms consisted of bacteria, actinomycetes, as well as fungi. Bacteria were the chief component of
microorganisms and were widely distributed, but fungi were scarce in some soil layers. Aspergillus was the dominant genus among the 11 genera of fungi isolated from the soil in different age stages of P. euphratica forests.
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Translated from Journal of Beijing Forestry University, 2007, 29(5): 127–131 [译自: 北京林业大学学报] 相似文献
19.
Calculating aggregation index by the sample-plot data used to lead to computing error due to the existence of a boundary effect.
Here, we suggest a method for adjusting boundary effect in the analysis of spatial patterns at different stages of development
of the broad-leaved Korean pine forest. This method is good for the reasonable management and biological control of the forests.
The total station was used to sample the relative coordinates data at four corners of the temporary sample plot and of each
tree in the field. Based on the sampling data, a correct approach to the boundary effect on aggregation index was put forward
to the spatial pattern analysis of the broad-leaved Korean pine forest in its different stages of development. The results
showed that the forest trees grew in a clumped pattern in the stage dominated by the pioneer trees, and that the trees were
distributed in a random pattern in the stage dominated by the companion trees or in the mature stage. The spatial pattern
of the broad-leaved Korean pine forest changing from clumped to random distribution is influenced by biological characteristic,
the adaptive strategy of tree species and the natural disturbance in its entire development.
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Translated from Journal of Nanjing Forestry University, 2005, 29(3): 57–60 [译自: 南京林业大学学报, 2005, 29(3): 57–60] 相似文献
20.
In order to study variation of morphological traits and the influencing factors of natural populations of Quercus liaotungensis Koidz. in Lingkong Mountain Nature Reserve of Shanxi region, five populations were included, and 24 morphological traits
of leaf and apical bud were investigated. The analysis of variance showed that variation of all the morphological traits within
population were significant, whereas significant difference existed in five property indices among populations (α = 0.05), which resulted from genetic and environmental factors. The results revealed that direction and degree of slope,
average diameter at breast height in populations, and population density were the main influencing factors. Intrapopulation
variation mainly contributed to morphological variation, and the phenotypic differentiation coefficient was 13.31%, which
indicated low level of differentiation. But several characteristics exhibited high differentiation level, such as width of
the tooth of leaf base (25.99%) and the middle apical bud (25.23%). The morphological indices, including the tooth of leaf
base, leaf tip, petiole, and leaf area were precarious and changed a lot within population, which arose from the variation
of individual’s development. However, only two morphological indices, the middle apical bud and the tooth of leaf base, are
unstable, which indicates the extensive influence of environmental factors.
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Translated from Journal of Beijing Forestry University, 2005, 27(5): 10–16 [译自: 北京林业大学学报] 相似文献