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1.
Xuanran Li Qijing Liu Yongrui Chen Lile Hu Fengting Yang 《Frontiers of Forestry in China》2008,3(1):16-23
Regressive models of the aboveground biomass for three conifers in subtropical China—slash pine (Pinus elliottii), Masson pine (P. massoniana) and Chinese fir (Cunninghamia lanceolata)—were established. Regression analysis of leaf biomass and total biomass of each branch against branch diameter (d), branch length (L), d
3 and d
2
L was conducted with functions of linear, power and exponent. A power law equation with a single parameter (d) was proved to be better than the rest for Masson pine and Chinese fir, and a linear equation with parameter (d
3) is better for slash pine. The canopy biomass was derived by adopting the regression equations to all branches of each individual
tree. These kinds of equations were also used to fit the relationship between total tree biomass, branch biomass, foliage
biomass and tree diameter at breast height (D), tree height (H), D
3 and D
2
H, respectively. D
2
H was found to be the best parameter for estimating total biomass. However, for foliage biomass and branch biomass, both parameters
and equation forms showed some differences among species. Correlations were highly significant (P<0.001) for foliage biomass, branch biomass and total biomass, among which the equation of the total biomass was the highest.
With these equations, the aboveground biomass of Masson pine forest, slash pine forest and Chinese fir forest were estimated,
in addition to the allocation of aboveground biomass. The above-ground biomass of Masson pine forest, slash pine forest and
Chinese fir forest was 83.6, 72.1 and 59 t/hm2 respectively, and the stem biomass was more than the foliage biomass and the branch biomass. The underground biomass of these
three forests which estimated with others’ research were 10.44, 9.42 and 11.48 t/hm2, and the amount of carbon-fixed were 47.94, 45.14 and 37.52 t/hm2, respectively.
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Translated from Chinese Journal of Applied Ecology, 2006, 17(8): 1382–1388 [译自: 应用生态学报] 相似文献
2.
Juan Shi Youqing Luo Jiying Song Xiaosu Yan Ping Jiang Yijiao Wang 《Frontiers of Forestry in China》2007,2(4):466-473
Reported in this paper are our findings of the study on changes in species diversity of different Masson pine communities
after the invasion of Bursaphelenchus xylophilus (Steiner and Buhren) Nickle and subsequent and different removal disturbance management approaches. Based on the results,
the species diversity indices for the arbor layers of the different communities can be arranged in the following order (from
high to low): 1) broad-leaved stand after the removal of all infected pine trees in the pure pine stand in Fuyang; 2) lightly
infected Masson pine and Schima superba mixed stand in Fuyang; 3) uninfected stand mixture of Masson pine and Castanopsis fargesii as a control; 4) lightly infested pure Masson pine stand in Fuyang; 5) Quercus variables stand formed following the selective removal of infected pine trees from a mixed Masson pine and Q. variables stand in Zhoushan Islands; 6) pure young Masson pine stand formed following the removal of all infected pine trees from a
pure Masson pine stand; 7) pure Liquidambar formosana stand after the removal of infected pine trees from a pure pine stand in Zhoushan Islands; 8) a mixed stand consisting of
Pinus thunbergii and the Masson pine in Zhoushan Island; and 9) moderately infected Masson pine stand in Zhoushan Islands.
All the three diversity indices (R
0 = richness, H′ = Shannon-Wiener index, and E = evenness) for the shrub layer did not show any significant differences among the various communities except for the pure
pine stand in Zhoushan Island, which had the lowest diversity. The three indices for the herb layer of the pure young Masson
pine, Q. variables stand, and L. formosana stand were higher than that of other stands.
The integrated analysis showed that the Masson pine forest in different geographical situations and extent of damage had distinct
disparity, just as in different disturbance degrees and restoring manners.
We created the “index of disturbing intensity of stump and fallen woods” (IDISFW) to represent the degree of disturbance of
tree removal to plant diversity. We found that the relationship between the species diversity index and the IDISFW shows both
a lower and higher degree of removal disturbance that follows the “mid-altitude bulge” theory. Specifically, both excessive
and insufficient removal of infected trees will cause a decline of plant species diversity to a certain degree. Covariance
analysis indicated that different IDISFW had no significant effects on the species diversity of the arbor layer, but had different
impacts on that of the shrub and herb layers, and therefore can be used to assess changes in species diversity of different
Masson pine communities after the invasion of pine wood nematode.
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Translated from Chinese Journal of Applied Ecology, 2006, 17(7): 1,157–1,163 [译自: 应用生态学报] 相似文献
3.
Zongming He Shaohui Fan Jingming Lu Xujing Yang Xianquan Weng 《Frontiers of Forestry in China》2007,2(4):396-400
The effects of five different site management treatments on the productivity of a six-year-old and secondrotation Chinese
fir (Cunninghamia lanceolata (Lamb.) Hook.) plantations planted after harvesting a 29-year-old and first-rotation Chinese fir plantation in Xiayang State
Forest Farm, Nanping, Fujian Province, were studied. Results showed that the Chinese fir grew best on plots treated with the
double slash treatment (BL3), followed by the whole tree harvest (BL1) and the slash burning treatment (SB), and poorest on treatment BL2 (normal slash retention) and BL0 (removal of all organic matter aboveground). The site index of the second rotation Chinese fir plantations in BL3 and BL0 treatments increased by 0.56 and 0.27, respectively, compared with the first rotation, and decreased in the rest of the three
treatments. Compared with the first rotation, the site index of the second rotation treated with BL1, SB and BL2 treatments decreased by 0.39, 0.45 and 0.63, respectively. Differences among the treatments were not statistically significant.
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Translated from Scientia Silvae Sinicae, 2006, 42(11): 47–51 [译自: 林业科学] 相似文献
4.
Qiong Zhao Xingyu Liu Dehui Zeng Jinhuan Liu Yalin Hu 《Frontiers of Forestry in China》2009,4(1):85-89
In order to find out the best foliar diagnostic index of phosphorus (P) nutrition in Mongolian pine (Pinus sylvestris var. mongolica) in the southeastern Keerqin Sandy Lands, the concentrations of total nitrogen (N), inorganic P, organic P and total P in
needles of different ages and soil available P were examined. The results show that in the study area, soil available P was
rather low (0.12–0.63 mg/kg) and was significantly correlated with inorganic P (cPi) and total P (cPt) concentrations in current
year needles of Mongolian pine. The significant correlation between soil available P and needle cPt derived from the significant
correlation between cPi and cPt. Compared with cPt, cPi did reflect the level of soil P supply more accurately and more directly.
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Translated from Chinese Journal of Applied Ecology, 2008, 19(3): 494–498 [译自: 应用生态学报] 相似文献
5.
[目的]通过对不同生物量和碳储量的估计方法进行对比分析,为确定在国家森林资源清查中生物量和碳储量的具体估计方法提供依据。[方法]以广东省2012年森林资源清查的100个杉木林和80个马尾松林的实测样地资料为基础,利用近年来我国建立的主要树种立木生物量模型,对改进IPCC法、生物量模型法和转换因子连续函数法(即方精云法)3种方法按一元和二元模型共6种方案进行了对比;同时,基于改进IPCC法一元和二元模型的生物量估计值,用平均含碳系数法、组分含碳系数法和固定含碳系数(0.5或0.47)法分别对碳储量进行估计。[结果]用二元生物量模型法得到的杉木林和马尾松林样地的总生物量分别为320 Mg和331 Mg,一元生物量模型法的结果分别相差0.9%和6.2%;改进IPCC法的估计结果,采用二元和一元模型时杉木林分别相差-3.6%和-11.9%,马尾松林分别相差-8.5%和-19.6%;而方精云法的估计结果,采用二元和一元模型时杉木林分别相差6.65倍和6.60倍,马尾松林分别相差-14.3%和-18.0%。平均含碳系数法和组分含碳系数法的碳储量估计结果,杉木林仅相差0.2%,马尾松林相差约0.4%;固定含碳系数法的估计结果因树种而异,对杉木林要低估0.6%5.4%,对马尾松林要低估3.3%9.1%。[结论]对生物量的估计,采用生物量模型法准确性最高,而林木水平的生物量模型其预估精度要高于林分水平的模型;IPCC法是基于材积源的通用方法,将其中的缺省参数改进为可变参数模型,可大大提高方法的适应性;方精云法只是基于IPCC法所建立的林分水平模型在大尺度上的一种具体应用方法,其精度要低于林木水平的生物量模型法,不适于中小尺度应用。对碳储量的估计,采用平均含碳系数法与组分含碳系数法差异很小,但采用固定含碳系数法则误差较大。 相似文献
6.
In order to obtain the effects of acid catalysts on wood liquefaction in phenol, we investigated the liquefaction of wood
powder from Chinese fir (Cunninghamia lanceolata) and poplar (Triploid Populus tomentosa Carr) in the presence of phenol with the following weak inorganic acids as catalysts: phosphoric acid (85%), sulfuric acid
(36%), hydrochloric acid (37%) and oxalic acid (99.5%). Results show that phosphoric acid (85%) and sulfuric acid (36%) are
better than the other catalysts. It was found that lower residue ratios can be obtained under defined reaction conditions:
phenol/wood ratio is 4, a 10% catalyst based on the weight of phenol, a temperature of 150°C for 2 h and phosphoric or sulfuric
acid. The residue ratios are 3.2% and 4.0%, respectively.
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Translated from Journal of Beijing Forestry University, 2004, 26(5) [译自: 北京林业大学学报, 2004, 26(5)] 相似文献
7.
In our experiments, one-year-old Larix olgensis seedlings were cultivated in sand, and supplied with solutions with different concentrations of nitrate or phosphate. The
effects of nitrogen and phosphorus supply on chlorophyll biosynthesis, total nitrogen content, and photosynthetic rate were
studied. The experimental results are listed below: 1) 5-aminolevulinic acid (ALA) synthetic rate increased as nitrate concentrations
supplied to larch seedlings increased from 1 to 8 mmol/L. But the rate decreased by 17% when nitrate concentration increased
to 16 mmol/L, in contrast to the control. Under phosphate treatments, ALA synthetic rates were similar to those under nitrate
treatments. The activities of porphobilinogen (PBG) synthase reached a maximum when larch seedlings were supplied with 8 mmol/L
of nitrate or 1 mmol/L of phosphate. 2) when larch seedlings were supplied with 8 mmol/L of nitrate and 0.5 mmol/L of phosphate,
the contents of chlorophyll a, chlorophyll b, total chlorophyll, and carotenoids reached a maximum. The total nitrogen contents
in leaves increased as nitrate concentrations increased. 3) When phosphate concentrations increased from 0.125 to 1 mmol/L,
the total nitrogen contents in leaves slightly increased; however, continuous increase of phosphate concentrations resulted
in the decrease in total nitrogen contents in leaves. When nitrate concentrations increased from 1 to 8 mmol/L, soluble protein
contents in leaves increased in general, and continuous increase of nitrate concentrations induced a decrease in soluble protein
contents in leaves. Under treatment of 0.25 mmol/L of phosphate, the soluble protein contents reached a maximum. 4) In general,
F
v/F
m increased as nitrate concentrations increased from 1 to 8 mmol/L, and continuous increase of nitrate concentration resulted
in decrease in F
v/F
m. The similar changes occurred under phosphate treatments. As nitrate concentrations increased from 1 to 8 mmol/L, photosynthetic
rates gradually increased, but when nitrate concentrations increased to 16 mmol/L, photosynthetic rate reduced by 16%, in
contrast to the control. Photosynthetic rates reached a maximum when seedlings were supplied with 1 mmol/L, and an oversupply
of phosphate (2 mmol/L) resulted in decrease in photosynthetic rates. The results suggested that supply levels of nitrogen
affected ALA biosynthetic rates, activities of PBG synthase, and affected contents of chlorophyll and carotenoids. Moreover,
nitrogen supply levels affected contents of total nitrogen and soluble proteins in leaves, and net photosynthetic rates. ALA
biosynthesis rates and activities of PBG synthase were affected by phosphate supply, but contents of chlorophyll and carotenoids
were not affected. And net photosynthetic rates were affected little by phosphate supply.
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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
8.
In order to identify the potential of sulfur (S) content in the rings of Masson pine (Pinus massoniana) in the Pearl River Delta as a bio-indicator of regional history of atmospheric pollution, dendrochemistry was used to determine
the temporal distribution of S content in the xylem of Masson pines from Zhaoqing Dinghushan and Nanhai Xiqiaoshan, Guangdong
Province, southern China. The results indicated that contents of xylem S increased temporally and peaked in the rings formed
in the most recent years at both sites. In the rings formed during the same period before the 1980s, S contents were not significantly
different between the two sites, while in the rings formed at the same period after the 1980s, S content at Xiqiaoshan were
significantly higher than those at Dinghushan. The chronosequences of the S indices at both sites could be easily marked as
three periods: before 1970, during 1971–1985, and during 1986–2002. Based on the temporal changes of the xylem S contents
and certain social-economic indices after the 1980s in the Delta, the history of atmospheric pollution at the study sites
could be reconstructed as follows: 1) before 1970, a period in which the air was relatively clear, 2) 1971–1985, a period
in which the air was gradually polluted, and 3) 1986–2002, a period in which the air was most severely polluted in the Delta.
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Translated from Journal of Beijing Forestry University, 2008, 30(2): 1–7 [译自: 北京林业大学学报] 相似文献
9.
[目的]研究低磷胁迫对杉木幼苗各种抗氧化酶等生理指标的变化影响,探讨抗氧化酶活性与杉木耐低磷能力的关系,揭示低磷胁迫下杉木养分吸收的适应机制,阐明杉木体内生物大分子对低磷胁迫的响应。[方法]通过设置不同磷浓度(0、0.25、0.50、1.00 mmol·L~(-1))Hoagland营养液,模拟低磷胁迫试验,测定低磷胁迫对杉木幼苗的生理指标的影响,研究低磷胁迫对杉木幼苗养分吸收的影响机制以及测定杉木幼苗不同部位的光谱特性。[结果]随着缺磷程度的增加,杉木幼苗中SOD活性、CAT活性以及叶绿素a、叶绿素b和叶绿素总量均先升后降,根系中POD活性呈现出升高的趋势、MDA含量先降再升后降,叶片中POD活性和MDA含量先降后升。低磷胁迫对杉木幼苗根系和叶片吸收利用营养元素有显著影响。杉木苗根系所含的Mn随着缺磷程度的增加呈上升趋势,而Al和Cu先降后升,Fe和K则有所下降,Ca先升后降。此外,杉木叶片中Fe和Mn的积累量呈降低的趋势,Cu和K先升后降。低磷胁迫对杉木幼苗根系和叶片组织在3 367、2 924、1 736、1 630、1 380、1 150 1 000 cm~(-1)处特征峰吸光值影响不同。[结论]低磷胁迫下,杉木幼苗的根系和叶片会通过改变保护酶(SOD、CAT和POD)活性抑制MDA形成,降低膜脂过氧化对细胞膜系统的破坏,通过增加对其他养分元素的吸收来规避损伤以及通过改变不同部位糖类、氨基酸和蛋白质等物质含量来适应低磷环境。 相似文献
10.
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
11.
Luozhong Tang Dan Zhao Chunfeng Yan Zhilong Liu Shengzuo Fang Mukui Yu 《Frontiers of Forestry in China》2009,4(2):185-190
The effects of site conditions and cultivation on the growth of sawtooth oak (Quercus acutissima Carr.) plantations were evaluated at the Hongyashan forest farm, in Chuzhou City, Anhui Province, China. The results indicate
that the position on the slope, the amount of gravel and the thickness of the soil were important factors in the growth of
the sawtooth oak. Lower slope positions with small amounts of gravel and a thick soil were better for the growth of this species
than middle slope positions with more gravel and a thin soil. Given the site conditions of the hilly and mountainous areas
in Chuzhou City, the mixed Chinese fir (Cunninghamia lanceolata Hook.) and sawtooth oak forests did not improve forest productivity compared with pure sawtooth oak forests. Both urea and
compound fertilizers promoted the growth of sawtooth oak, as did site preparation and intercropping. Two years after planting,
the height growth of ordinary seedlings with a starting height of 0.6 m was higher than that of supper seedlings with a starting
height of 1.0 m. Compared with planting, the early growth of the coppices was faster, but the later growth of the coppices
was slower.
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Translated from Journal of Fujian College of Forestry, 2008, 28(2): 130–135 [译自: 福建林学院学报] 相似文献
12.
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
13.
The soil microbial biomass and nutrient status under the native broadleaved forest and Cunninghamia lanceolata plantations at the Huitong National Research Station of Forest Ecosystem (in Hunan Province, midland of China) were examined
in this study. The results showed that after the native broadleaved forest was replaced by mono-cultured C. lanceolata or C. lanceolata, soil microbial biomass and nutrient pool decreased significantly. In the 0–10 cm soil layer, the concentrations of soil
microbial carbon and nitrogen in the broadleaved forest were 800.5 and 84.5 mg/kg, respectively. These were 1.90 and 1.03
times as much as those in the first rotation of the C. lanceolata plantation, and 2.16 and 1.27 times as much as those in the second rotation of the plantation, respectively. While in the
10–20 cm soil layer, the microbial carbon and nitrogen in the broadleaved forest were 475.4 and 63.3 mg/kg, respectively.
These were 1.86 and 1.60 times as much as those in the first rotation, and 2.11 and 1.76 times as much as those in the second
rotation, respectively. Soil nutrient pools, such as total nitrogen, total potassium, NH4
+-N, and available potassium, also declined after the C. lanceolata plantation replaced the native broadleaved forest, or Chinese fir was planted continuously. Less litter and slower decay
rate in pure Chinese fir plantation were the crucial factors leading to the decrease of soil microbial biomass and nutrient
pool in this area. Human disturbance, especially slash-burning and site preparation, was another factor leading to the decrease.
There were significant positive correlations between soil microbial carbon and nitrogen and soil nutrients. To improve soil
quality and maintain sustainable productivity, some measures, including planting mixed conifer with hardwood, preserving residues
after harvest, and adopting scientific site preparation, should be taken.
Translated from Chinese Journal of Applied Ecology, 2006, 17(12): 2,292–2,296 [译自: 应用生态学报] 相似文献
14.
Ado Shigihara Yuiko Matsumura Kiyoshi Matsumoto Manabu Igawa 《Journal of Forest Research》2009,14(3):188-192
The decline of virgin fir (Abies firma) forest at Mt. Oyama has been reported. Related field observations suggest that high acidity fog is linked with its decline.
However, cedar (Cryptomeria japonica) in the same area shows no symptoms of decline. For assessing effects of acid fog on membrane-bound calcium (mCa) of the
leaf mesophyll cells, 9-year-old seedlings of fir (Abies firma) and 8-year-old seedlings of cedar (Cryptomeria japonica) were exposed twice a week to simulated acid fog (SAF at pH 3 with pH 5 as control) for 2 h per day in a chamber during May–December
2007 (except August). Current and 1-year-old needles were collected from seedlings and analyzed at 1-month intervals. For
current-year needles of fir, mCa levels in cells exposed to SAF at pH 3 were significantly lower than in cells exposed to
pH 5, especially during September 2007–March 2008. In contrast, it is noteworthy that mCa levels of cedar were maintained
as virtually constant irrespective of SAF acidity, indicating that fir is more sensitive to acid fog than is cedar. Based
on these results, mCa loss by acid fog might also be caused in the declining virgin fir forest at Mt. Oyama. 相似文献
15.
A landscape model (LANDIS) was used to study the long-term forest dynamics under five planting types (100% larch (P1); 70% larch and 30% Mongolian Scotch pine (Pinus sylvestris var. mongolica) (P2); 50% larch and 50% Mongolian Scotch pine (P3); 30% larch and 70% Mongolian Scotch pine (P4); 100% Mongolian Scotch pine (P5)), which were also employed in severely burned area under current planting intensity, and under natural regeneration (as
a comparison) in Tuqiang Forest Bureau in the northern slopes of Great Xing’an Mountains after the catastrophic fire in 1987.
Results showed that different planting types had a significant influence on the abundance of larch, Mongolian Scotch pine
and white birch. The abundance of larch increased with time, whereas the abundance of Mongolian Scotch pine was in a converse
way. The abundance of larch and Mongolian Scotch pine under these planting scenarios was higher than that under natural regeneration.
Under these planting scenarios, the abundance of larch increased with the increasing proportion of larch, and the abundance
of Mongolian Scotch pine was in a similar way. Contrary to larch and Mongolian Scotch pine, white birch had higher abundance
under natural regeneration than that under these planting scenarios. Also, the different proportions of larch and Mongolian
Scotch pine had an influence on the abundance of white birch. White birch had higher abundance with the increasing proportion
of Mongolian Scotch pine. As for the total abundance of larch and Mongolian Scotch pine, the difference was not significant
under P2, P3 and P4 scenarios, but was higher than that under P1 and P5 scenarios, which indicated that individual-species planting should not
be used in the forest landscape.
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Translated from Chinese Journal of Applied Ecology, 2006, 17(5): 855–861 [译自: 应用生态学报] 相似文献
16.
Zhongling Guo Qingkang Li Jinping Zheng Wande Liu Chunnan Fan Yuandan Ma Guirui Yu Shijie Han 《Frontiers of Forestry in China》2007,2(1):47-54
From 2001 to 2003, the litter decomposition dynamics of dominant tree species were conducted using a litterbag burying method
in the broadleaf-Korean pine forest, spruce-fir forest and Ermans birch forest, which represents three altitudinal belts in
Changbai Mountain, northeast China. The spatial and temporal dynamics of litter decomposition and the effects of litter properties
were examined. Furthermore, the decomposition trend of different species was simulated by the Olson model, and results showed
that annual mass loss rates increased over time, but was not significantly correlated. Leaf decomposition rates increased
after decomposing for 638 days (1.75 years), and the order of dry weight remaining rates of leaf litter for different species
is: Asian white birch (Betula platyphylla) (24.56%) < Amur linden (Tilia amurensis) (24.81%) < Korean pine (Pinus koraiensis) (38.48%) < spruce (Picea jezoensis var. microsperma) (41.15%) < Ermans birch (Betula ermanii) (41.53%) < fir (Abies nephrolepis) (42.62%). The dry weight remaining rates of twig litter was smaller than that of leaf litter, and followed the order of
Amur linden (44.98%) < fir (64.62%) < Korean pine (72.07%) < spruce (73.51%) < Asian white birch (77.37%) < Ermans birch (80.35%).
The simulation results by the Olson model showed that, in leaf, the 95%-decomposition rates ranged from 4.5 to 8.0 years,
and annual decomposition rate (k) followed the order of Amur linden (0.686) > Asian white birch (0.624) > Korean pine (0.441) > spruce (0.406) > fir (0.397)
> Ermans birch (0.385); in twig, it ranged from 7.8 to 29.3 years, and k follows the order: Amur linden (0.391) > fir (0.204) > Korean pine (0.176) > spruce (0.157) > Asian white birch (0.148) >
Ermans birch (0.102). In general, the differences of decomposition rate are evident between leaf and twig litter and among
species, and were higher in broad-leaved species compared with coniferous species at the same elevation, and decreased with
the ascending of elevation.
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Translated from Acta Ecologica Sinica, 2006, 26(4): 1,037–1,046 [译自: 生态学报] 相似文献
17.
The effect of precipitation variation on the chemistry of Mongolian oak (Quercus mongolica) leaf litters was examined by analyzing litters of Mongolia oak saplings under four precipitation gradients. The decomposing
process of these leaf litters in the Mongolian oak dominated forest was assessed using litter bag method. Compared with the
litters of the Mongolian oak saplings from the natural precipitation site (A), litters produced by Mongolian oak from the
driest precipitation gradient (A450) had significantly higher concentrations of nitrogen (N), phosphorus (P) and potassium (K) while lower acid-insoluble fraction
(AIF) concentration. The decomposition study showed that A450 exhibited significantly higher decomposition rate, mineralization rates of N, P and K as well as much shorter N and P net
immobilization periods. On the contrary, litters produced by seedlings from wettest gradient (A850) showed a totally opposite pattern. Litters from saplings that received comparable precipitation (A650) to those at the natural site (A) had significantly higher N concentration and faster decomposition rate as well as release
rates of N, P and K. The mass loss patterns for the four litter types fitted the exponential model and the decay constant
(k) can be well predicted by initial AIF/N. During the decomposition period, N concentration was best related to the percentage
of mass remaining of the litters with relatively higher AIF concentrations and lower N concentrations, but the percentage
of mass remaining of litters with lower AIF concentrations and higher N concentrations correlates strongly with AIF con centration.
Our study proved that changes in precipitation significantly altered the litter quality, and therefore indirectly changed
the decay process of leaf litters.
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Translated from Chinese Journal of Applied Ecology, 2007, 18(2): 261–266 [译自: 应用生态学报] 相似文献
18.
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
19.
Oxygen sensing technology was employed to study the rapid methods for seed vigor assessment of Chinese fir (Cunninghamia lanceolata) and Masson pine (Pinus massoniana). Firstly, seeds of five lots were performed using accelerated aging (AA) into three vigor levels. Then, four oxygen sensing indices, including increased metabolism time (IMT), oxygen metabolism rate (OMR), critical oxygen pressure (COP), relative germination time (RGT) and the control indices such as laboratory germination indices, dehydrogenase activity (DA), and electrical conductivity (EC) were analyzed by the tests of 15 samples. The results of correlation analysis between these indices and field emergence performances based on two-year and two-spot data showed that RGT and OMR should be indicated as the optimal oxygen sensing indices to rap- idly and automatically evaluate seed vigor of Chinese fir and Masson pine, respectively. On the basis, one-variable linear regression equations were built to forecast their field emergence performances by the two oxygen sensing indices. 相似文献
20.
Two-year-old seedlings ofPinus koraiensis, Pinus sylvestriformis andFraxinus mandshurica were treated in open-top chambers with elevated CO2 concentrations (700 μL·L−1, 500 μL·L−1) and ambient CO2 concentrations (350 μL·L−1) in Changbai Mountain from June to Sept. in 1999 and 2001. The net photosynthetic rate, dark respiration rate, ribulose-1,5-bisphosphate
carboxlase (RuBPcase) activity, and chlorophyll content were analyzed. The results indicated the RuBPcase activity of the
three species seedlings increased at elevated CO2 concentrations. The elevated CO2 concentrations stimulated the net photosynthetic rates of three tree species exceptP. sylvestriformis grown under 500 μL·L−1 CO2 concentration. The dark respiration rates ofP. koraiensis andP. sylvestriformis increased under concentration of 700 μL·L−1 CO2, out that ofF. mandshurica decreased under both concentrations 700 μL·L−1 and 500 μL·L−1 CO2. The seedlings ofF. mandshurica decreased in chlorophyll contents at elevated CO2 concentrations.
Foundation item: This paper was supported by the National Natural Science Foundation of China (No. 30070158). Knowledge Innovation Item of
Chinese Academy of Sciences (KZCX2-406) and “Hundred Scientists” Project of Chinese Academy of Sciences.
Biography: Zhou Yu-mei (1973-) Ph. Doctor, Assistant Research fellow Institute of Applied Ecology. Chinese Academy of Sciences. Shenyang
110016. P.R. China.
Responsible editor: Song Funan 相似文献