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1.
A virgin Pinus koraiensis forest in the Xiaoxing’an Mountains was selected to study its rainfall redistribution effect via 97 rainfall occurrences
during a growing season. The following results were obtained: 1) The canopy interception of the P. koraiensis virgin forest amounted to 98168 mm during a growing season (May to September), which was 19.6 per cent of the total rainfall
and 1.3 times that of a secondary Betula platyphylla forest. Compared with other forest types in China (11.4%–36.5%), the ratio of the canopy interception in the virgin pine
forest was at a medium level. 2) The throughfall of the virgin pine forest was 395.77 mm, which accounted for 78.7% of total
precipitation, and the stem-flow was 8.78 mm, accounting for 1.74% of total precipitation. Compared with the secondary birch
forest, the virgin pine forest had lower throughfall but higher stem-flow. 3) Cubic regression equations (p < 0.01) which describe the relation between throughfall, stem-flow and canopy interception in the virgin pine forest and
rainfall in an open field were fitted. A linear regression equation (p < 0.01) was found to be a better fit for the relationship between throughfall of the secondary birch forest and rainfall
outside the forest. Factors affecting throughfall and stem-flow were analyzed, with results providing a good reference to
the study of rainfall redistribution in coniferous and broadleaved mixed forests.
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Translated from Science of Soil and Water Conservation, 2006, 4(6): 61–65 [译自: 中国水土保持科学] 相似文献
2.
Tangren Cheng Jing Feng Qinyan Ma Zhongke Feng Yanlin Zhang Xu Luo Yutao Wang 《Frontiers of Forestry in China》2008,3(2):206-212
In order to accurately estimate the size of the carbon pool and the capacity of the carbon sink in the forested areas of Xiaolong
Mountain in Gansu Province, we have established regression equations of organ biomass of eight tree species. We measured and
investigated the biomass of different forest stand types based on data from 1259 standard sample plots and 836 standard sample
trees. The results show that stand biomass, expressed in t·hm−2 for eight types of forest stands on Xiaolong Mountain, are as follows: Quercus aliena var. acuteserrata 84.05, Pinus tabulaeformis 62.44, Quercus variabilis 81.77, Populus sp. and Betula sp. combined 77.44, Larix sp. 69.00, Pinus armandii 70.07, Picea sp. 96.49 and Abies sp. 98.72. We also looked at other broad-leaved mixed forests. Our study shows that the biomass of a single tree of each
tree species is closely related to the diameter at breast height (DBH) and to tree height. The biomass of single trees as
well as stand volumes is closely related to average DBH, average tree height and to stand density.
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Translated from Journal of Beijing Forestry University, 2007, 29(1): 31–36 [译自: 北京林业大学学报] 相似文献
3.
In order to understand the relationship between population succession and its genetic behavior, random amplified polymorphic
DNA (RAPD) technique was used to analyze the genetic diversity of Quercu glandulifera var. brevipetiolata populations in three forest communities with different succession stages (coniferous forest, coniferous and broad-leaved
mixed forest, evergreen broad-leaved forest). The results showed that 145 repetitive loci were produced in 60 individuals
of Q. glandulifera using 11 primers, among which 120 loci were polymorphic, and the total percentage of polymorphic loci was 82.76% with an
average of 64.14%. Estimated by the Shannon information index, the total genetic diversity of the three populations was 0.4747,
with an average of 0.3642, while it was 0.3234, with an average of 0.2484, judged from the Nei index. Judged from percentage
of polymorphic loci, Shannon inform at ion index and Nei index, the genetic diversity followed a decreasing order: coniferous
forest > broad-leaved mixed forest > evergreen broad-leaved forest. Analysis of molecular variance (AMOVA) showed that 69.73%
of the genetic variance existed within populations and 30.27% of the genetic variance existed among populations. The coefficient
of gene differentiation (GST) was 0.2319 and the gene flow (N
m) was 1.6539. The mean of genetic identity among populations of Q. glandulifera was 0.8501 and the mean of genetic distance was 0.1626. The genetic identity between the Q. glandulifera population in the coniferous forest and that in the coniferous and broadleaved mixed forest was the highest. UPGMA cluster
analysis based on Nei’s genetic distance showed that the population in the coniferous forest gathered with that in the coniferous
and broad-leaved mixed forest firstly, then with that in the evergreen broad-leaved forest. The genetic structure of Q. glandulifera was not only characteristic of the biological characteristics of this species, but was also influenced by the microenvironment
in different communities.
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Translated from Journal of Northwest Forestry University, 2008, 23(1): 18–22 [译自: 西北林学院学报] 相似文献
4.
Three Pinus tabulaeformis populations which experienced tending, shelterwood cutting, and closed tending were separately investigated to study the
effects of these three forest practices on the age structures, static life tables, survivorship curves, and species diversities
of P. tabulaeformis populations in Huanglongshan Mountain. Time sequence model was adopted to predict the dynamic population numbers of different
P. tabulaeformis populations with different forest practices. The results revealed that the three populations are essentially identical in
population structure, their young and old individuals make up a small proportion and their mid-aged individuals make up a
large proportion and consequentially P. tabulaeformis populations generally stand stable. In the P. tabulaeformis communities with three tending practices, the highest species abundance index appears with tending and shelterwood cutting
and the highest evenness index and species diversity appears with closed tending. The P. tabulaeformis populations with tending and shelterwood cutting practices belong to one developmental type and the P. tabulaeformis populations with closed tending practices belong to a stable type. It indicated that in the future, closed tending as the
major practice and tending and shelterwood cutting as the supporting practices should be applied for P. tabulaeformis populations in Huanglongshan Mountain so that the communities will develop continuously.
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Translated from Acta Botanica Boreali-Occidentalia Sinica, 2006, 26(5): 1,007–1,013 [译自: 西北植物学报] 相似文献
5.
Forest precipitation chemistry is a major issue in forest hydrology and forest ecology. Chemical contents in precipitation
change significantly when different kinds of external chemical materials are added, removed, translocated and transformed
to or in the forest ecosystem along with precipitation. The chemistry of precipitation was monitored and analyzed in a 31-year-old
Pinus tabulaeformis forest in the West Mountain of Beijing. Movement patterns of nutrient elements in hydrological processes can be discovered
by studying this monitored data. Also, the information is useful for diagnosing the function of ecosystems and evaluating
the impact of the environment on the ecosystem.
Samples of rainfall, throughfall and stemflow were collected on the site. In the lab, Ca2+ and Mg2+ were analyzed by flame atomic absorption and K+ and Na+ by flame emission. NH4
+-N was analyzed by indophenol blue colorimetry and NO3
−-N was analyzed by phenoldisulfonic acid colorimetry. The results showed that: 1) The concentration gradient of nutrient elements
clearly changed except for Na+. The nutrients in stemflow were significantly higher than those of throughfall and rainfall as the precipitation passed through
the P. tabulaeformis forest. The monthly patterns showed distinct differentiation. There are indications that a large amount of nutrients was
leached from the canopy, which is a critical function of intra-ecosystem nutrient cycling to improve the efficiency of nutrient
use. 2) The concentrations of NO3
−-N and K+ changed more than those of the other nutrient elements. The concentration of NO3
−-N in throughfall and stemflow was 4.4 times and 9.9 times higher than those in rainfall, respectively. The concentration
of K+ in throughfall and stemflow was 4.1 times and 8.1 times higher than those in rainfall, respectively. 3) The leaching of nutrient
elements from the stand was an important aspect of nutrient return to the P. tabulaeformis forest, which returned a total amount of nutrient of 54.1 kg/hm2, with the contribution of Ca2+ and K+ much greater than that of other elements. Also, K+ was the most active element in leaching intensity. 4) Nutrient input through precipitation was the main source in the West
Mountain of Beijing and the amount of nutrient added was 66.4 kg/hm2, of which Ca2+ and N contributed much more than the other nutrient elements. When precipitation passes through the P. tabulaeformis forest, 121 kg/hm2 of nutrient is added to the forest floor. Ca2+ recorded the greatest nutrient increase, with 61.2 kg/hm2, followed by N (NH4
+-N and NO3
−-N), K+ and Mg2+, with 31.3 and 16.5, and 8.11 kg/hm2, respectively. The least was Na+, 3.34 kg/hm2.
Translated from Acta Ecologica Sinica, 2006, 26(7): 2,101–2,107 [译自: 生态学报] 相似文献
6.
Zhuowen Zhang Yusheng Chen Zhiyong Zhang Hongxia Cui Yunfei Lei Dongyun Wang Juanjuan Sui 《Frontiers of Forestry in China》2006,1(4):413-418
We surveyed the forest litter amount at the Lianxiahe watershed in the Three Gorges Reservoir Area and analyzed some hydrological
characteristics such as the maximum water-holding capacity and water absorption rate of litter in six types of forests, i.e.
the Cupressus funebris forest, the coniferous mixed forest, the coniferous and broad-leaved mixed forest, the broad-leaved forest, the Pinus massoniana forest, the bush forest. Results showed that the litter amount follows the order of the coniferous and broad-leaved mixed
forest > the pure C. funebris forest, the P. massoniana forest > the coniferous mixed forest > the broad-leaved forest > the bush forest. The maximal water holding capacity of the
undecomposed litter is in the order of the C. funebris forest > the coniferous mixed forest > the bush forest > the coniferous and broad-leaved mixed forest > the broad-leaved
forest > the P. massoniana forest. The maximal water-holding capacity of the half-decomposed litter is the P. massoniana forest > the coniferous and broad-leaved mixed forest > the C. funebris forest > the coniferous mixed forest > the broad-leaved forest > the bush forest. In this watershed, the water holding capacity
of the litter in the C. funebris forest is the highest, followed by the coniferous mixed forest, coniferous and broad-leaved mixed forest, P. massoniana forest, broad-leaved forest and bush forest. When the soil is covered only by litter, both the maximal rainfall amount and
intensity in different forest stands are different if there is no water infiltration and runoff from the ground surface.
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Translated from Journal of Huazhong Agricultural University, 2005, 27(2): 207–212 [译自: 华中农业大学学报, 2005, 24(2): 207–212] 相似文献
7.
Effects of different vegetation restoration models on soil microbial biomass in eroded hilly Loess Plateau, China 总被引:2,自引:0,他引:2
Vegetation restoration is a key measure to improve the eco-environment in Loess Plateau, China. In order to find the effect
of soil microbial biomass under different vegetation restoration models in this region, six trial sites located in Zhifanggou
watershed were selected in this study. Results showed that soil microbial biomass, microbial respiration and physical and
chemical properties increased apparently. After 30 years of vegetation restoration, soil microbial biomass C, N, P (SMBC,
SMBN, SMBP) and microbial respiration, increased by 109.01%–144.22%, 34.17%–117.09%, 31.79%–79.94% and 26.78%–87.59% respectively,
as compared with the farmland. However, metabolic quotient declined dramatically by 57.45%–77.49%. Effects of different models
of vegetation restoration are different on improving the properties of soil. In general, mixed stands of Pinus tabulaeformis-Amorpha fruticosa and Robinia pseudoacacia-A. fruticosa had the most remarkable effect, followed by R. pseudoacacia and Caragana korshinkii, fallow land and P. tabulaeformis was the lowest. Restoration of mixed forest had greater effective than pure forest in eroded Hilly Loess Plateau. The significant
relationships were observed among SMBC, SMBP, microbial respiration, and physical and chemical properties of soil. It was
concluded that microbial biomass can be used as indicators of soil quality.
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Translated from Journal of Natural Resources, 2007, 22(1): 20–27 [译自: 自然资源学报] 相似文献
8.
We studied the nutrient cycle of a planted forest of Pinus tabulaeformis in the Miyun Reservoir Watershed, Beijing. Results show that the total biomass of P. tabulaeformis stands at age 29 in the experimental area is 92627 kg/hm2, and the total nutrient store is 695.17 kg/hm2 including nitrogen (N), phosphorus (P), kalium (K), calium (Ca) and magnesium (Mg). The sequence of their contents in different
organs was given as follows: needle>branch> trunk>root. The annual amount of 85.37 kg/hm2 of five nutrient elements were assimilated by P. tabulaeformis, about 0.34% of the total store in soil, and 3.30% of available nutrient store in soil depth from 0 to 30 cm. The nutrient
annual retention is 35.92 kg/hm2, annual returning 49.46 kg/hm2, the rain input 26.04 kg/hm2 to the five nutrient elements. The parameter absorption coefficient, utilization coefficient, cycle coefficient and turnover
period were cited to describe the nutrient elements cycle characteristic of the planted forest ecosystem of P. tabulaeformis. The absorption coefficient is the ratio of plant nutrient element content to soil nutrient element content, and its sequence
of five nutrient elements was given as follows: N>P>K>Ca>Mg. Utilization coefficient is the ratio of the nutrient element
annual uptake amount to the nutrient element storage in standing crops, and its sequence of five nutrient elements was: Mg>K>
P>N>Ca. The big utilization coefficient means more nutrients stored in the plant. The cycle coefficient is the ratio of the
nutrient element annual return amount to the nutrient element annual uptake amount, its sequence: Ca>N>P>K>Mg. Turnover period
is the ratio of the nutrient storage in the crops to the annual returning, its sequence: Mg>K>P>N>Ca.
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Translated from Journal of Beijing Forestry University, 2008, 30(3): 51–56 [译自: 北京林业大学学报] 相似文献
9.
The Huanglong Mountain forest zone is one of the major natural secondary forest zones in the southern Loess Plateau in Shaanxi
Province, China. Since 1950, a mode of fully closed hillside afforestation (FHA) has been applied in the forest. On some special
sites, the forest age exceeds 80 years. Pinus tabulaeformis forests form the most important vegetation cover in the warm temperate regions of China. Similarly, populations of P. tabulaeformis are dominant in existing forest ecosystems. Quercus liaotungensis, Syringa oblata, Populus davidiana, Prunus davidiana, Betula platyphylla and Toxicodendron vernicifluum can be occasionally found in the tree layer and shrub species are abundant. Based on the data collected from 31 plots and
93 soil samples, the state of health of the forest ecosystem is discussed and the appropriate FHA age has been determined.
Twelve indices representing vegetation and soil properties in natural, secondary P. tabulaeformis forest ecosystems were generated by sensitivity analysis and an assessment index system for the FHA mode was established.
According to the equal distance method, a clustering technique and five grades of an integrated index for evaluating the FHA
mode were compartmentalized. The effect of the FHA mode on natural secondary P. tabulaeformis forests was evaluated by an integrated index method with the aid of an analytical hierarchy process (AHP). The results are
as follows: values of the integrated index in the FHA mode of 16, 25, 30, 45, 60 and 75 year old stands were 7.25, 6.88, 7.82,
5.51, 4.78 and 2.79 respectively. With an increase over age of the FHA stands, the effect of the FHA mode deteriorated. We
conclude that natural forests should not be protected in the FHA way after 45 years. At that stage, mixing suitable tree species,
selection cutting and other silvicultural and management measures should be adopted.
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Translated from Acta Ecologica Sinica, 2007, 27(1): 288–295 [译自: 生态学报] 相似文献
10.
In this paper, based on a long-term monitoring of water cycle in the water and soil conservation forest stands of Pinus tabulaeformis and Robinia pseudoacacia, the soil moisture deficit is calculated. Following the principles of runoff-collecting forestry and applying the forest
structure investigation results, the authors developed a formula to calculate appropriate density for forests on the basis
of different diameters at breast height (DBH). Using this method to manage forests, the natural water requirement of forests
can be met and soil drought can be avoided. In addition, with long-term monitoring of soil moisture in stands, the authors
also give an appropriate managing density specifically for the water and soil conservation forests of P. tabulaeformis and R. pseudoacacia in the loess area which is according to soil moisture content, or with the lowest soil moisture content and invalid moisture
frequency as the indexes.
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Translated from Science of Water and Soil Conservation, 2007, 5(2): 55–59 [译自: 中国水土保持科学] 相似文献
11.
Xiaoyuan Chu Yujie Wang Yiping Xia Yun Wu Lin Chen 《Frontiers of Forestry in China》2009,4(2):171-177
In order to provide a basis for water conservation in the restoration of vegetation for an urban water resource area, we studied
the generation of runoff characteristics in four typical forests over three time periods in Jinyun Mountain, Chongqing City,
based on the observation data of rainfall and runoff processes during the period 2002–2005. The results show that: 1) Rainfall
was distributed evenly during the years 2002–2005. Annual rainfall variability was 4.46% and coefficient of variation was
0.0618. Average monthly rainfall tended towards a normal distribution N (113.8, 45972). 2) Both precipitation and runoff can be clearly divided into a dry and a wet season. The dry season was from October to
March and the wet season from April to September. Most of annual runoff of the four forest stands occurred in the wet season.
The surface runoff in the wet season accounted for more than 85% of the annual runoff, and more than 75% of underground runoff.
3) Both peak values of surface runoff and underground runoff occurred in June. The relation between monthly rainfall and surface/underground
runoff was fitted by the model W=aP
2 + bP + c. The order of annual surface runoff was as follows: Phyllostachys pubescens forest > shrub forest > mixed Pinus massoniana-broadleaf forest > evergreen broad-leaved forest. The annual underground runoff was evergreen broad-leaved forest > mixed
Pinus massoniana-broadleaf forest > Phyllostachys pubescens forest > shrub forest. 4) Under similar rainstorms events, the order of the surface runoff coefficient was: evergreen broad-leaved
forest < mixed Pinus massoniana-broadleaf forest < shrub forest < Phyllostachys pubescens forest. The underground runoff coefficient was: evergreen broad-leaved forest > mixed Pinus massoniana-broadleaf forest > Phyllostachys pubescens forest > shrub forest. The relation between rainstorms and surface runoff was fitted by the linear relationship: Q = mp − n. Both mixed Pinus massoniana-broadleaf forest and evergreen broad-leaved forest have better flood regulation effects on an annual and monthly basis and
per individual rainstorm. The function of Phyllostachys pubescens forest is the worst on all three bases.
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Translated from Journal of Beijing Forestry University, 2008, 30(4): 103–108 [译自: 北京林业大学学报] 相似文献
12.
By using random amplified polymorphic DNA (RAPD) technique, this paper studied the genetic diversity and genetic differentiation
of Lithocarpus harlandii populations in three forest communities (coniferous forest, coniferous and broad-leaved mixed forest, and evergreen broad-leaved
forest) with different succession stages in Tiantai Mountain in Zhejiang Province. The results showed that a total of 173
repetitive loci were produced in 60 individuals of L. harlandii by 12 random primers, among which, 152 loci were polymorphic, and the total percentage of polymorphic loci was 87.86%. The
average percentage of polymorphic loci of the populations was 65.32%, and their total genetic diversity estimated by Shannon
information index was 0.4529, with an average of 0.3458, while that judged from Nei’s index was 0.3004, with an average of
0.2320. The percentage of polymorphic loci, Shannon information index, and Nei’s index of the populations were in the sequence
of coniferous forest community > coniferous and broad-leaved mixed forest community > evergreen broad-leaved forest community.
Analysis of molecular variance (AMOVA) showed that 72.85% of genetic variance was found within the populations, and 27.15%
of genetic variance resided among the populations. The coefficient of gene diferentiation was 0.2277, and the gene flow was
1.6949. The genetic structure of L. harlandii was influenced not only by the biological characteristics of this species, but also by the microenvironment of different
communities. The mean of genetic identity among three populations of L. harlandii was 0.8662, and the mean of their genetic distance was 0.1442. The genetic similarity between coniferous and broad-leaved
mixed forest community and evergreen broad-leaved forest community was the highest, while that between evergreen broad-leaved
forest community and coniferous forest community was the lowest. The unweighted pair group method with arithmeticmean (UPGMA)
cluster analysis based on Nei’s genetic distance showed that conierous and broad-leaved mixed forest community first gathered
with evergreen broad-leaved forest community, and then with coniferous forest community.
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Translated from Chinese Journal of Ecology, 2007, 26(4): 509–514 [译自: 生态学杂志] 相似文献
13.
Zhuowen Zhang Yunfei Lei Kaijun Su Guang Wang Dongyun Wang Hongyan Ma 《Frontiers of Forestry in China》2009,4(3):317-322
The hydrological characteristics of litter in four different forest succession stages, i.e., a Pinus massoniana forest, a mixed conifer and broad-leaved forest with conifer being the dominant species, a mixed conifer and broad-leaved
forest with deciduous trees as dominant species, and an evergreen broad-leaved forest, have been studied by means of substituting
space for time. The results show that while a community is developing to a zonal climax, the amount of litter becomes larger
and its decomposition intensity becomes stronger; there is a positive relation between its water-holding capacity and velocity
and its community maturity for the half-decomposed litter layer.
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Translated from Journal of Central South University of Forestry and Technology, 2007, 27(6): 38–43 [译自: 中南林业科技大学学报] 相似文献
14.
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
15.
Feng An Jing Cai Zaimin Jiang Yuanying Zhang Pingjuan Zhao Shuoxin Zhang 《Frontiers of Forestry in China》2007,2(2):198-203
The relationship between xylem embolism and eco-physiology indices (i.e. photosynthetic available radiation, temperature,
relative humidity, photosynthetic rate, transpiration rate, stomatal conductance and water use efficiency) in eight tree species
was investigated in situ. The species studied, Robinia pseudoacacia L., Acer truncatum Bge., Hippophae rhamnoides L., Ulmus pumila L., Pinus tabulaeformis Carr., Pinus bungeana Zucc.ex Endl., Ligustrum lucidum Ait., and Salix matsudana Koidz. f. pendula Schneid, grow well on the Xilin campus of Northwest A&F University. Results indicated that photosynthetic available radiation,
air temperature and relative humidity can affect xylem embolism by daily adjustment of stomatal conductance, transpiration
rate and water relations of a tree. Embolism was a common case in the daily growth of the plants, and there was some correlation
between xylem embolism and photosynthetic rate, transpiration rate, stomatal conductance, and water use efficiency. Embolism
may thus be an adaptive mechanism by some tree species to water stress.
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Translated from Journal of Northwest Forestry University, 2006, 21(1): 37–42 [译自: 西北林学院学报] 相似文献
16.
[目的]研究不同道路防护林的滞尘能力及滞尘的动态变化和空间分布规律。[方法]在春季对3种道路防护林(油松林、圆柏林、银杏林)距道路不同宽度的滞尘量进行连续观测,对比3种道路防护林滞尘能力,分析降雨、极大风速、相对湿度、PM10等因子对滞尘动态的影响以及3种道路防护林滞尘的空间分布特征。使用单位叶干质量滞尘量(mg·g-1)表征叶面滞尘能力。[结果]表明:(1)3种植物叶面滞尘能力差异显著,圆柏银杏油松,分别为4.79±0.20、2.48±0.07、1.42±0.04 mg·g-1,单株和单位林分面积滞尘量均为圆柏林油松林银杏林;(2)3种道路防护林在外界影响下滞尘量处于动态变化之中,油松林具有比银杏和圆柏林更高的滞尘稳定性;(3)降雨量较低时3种道路防护林滞尘量均增加,降雨量较高时3种道路防护林滞尘量均降低,油松和银杏林的滞尘量更容易受降雨影响而降低;随着风速增大,3种道路防护林滞尘作用不断加强,风速继续增大时,油松和圆柏林滞尘量均有减少,银杏林滞尘量仍有显著增加。(4)3种道路防护林滞尘量在五环路侧(北)均高于香山路侧(南),油松和圆柏林均呈现为道路防护林中间位置为最低点,银杏林中间位置滞尘量最高。(5)油松和圆柏林滞尘量外部比内部变化大,银杏林滞尘量内部比外部变化大。[结论]道路防护林的滞尘效益受树种、林分结构、所处环境、天气条件等多方面因素共同影响,在营建和管理过程中应充分考虑各种因素,充分发挥滞尘作用。 相似文献
17.
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
18.
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
19.
We studied the distribution of soil nutrients, the number of soil microorganisms, soil enzyme activities, and their relationships
in pure and mixed plantations. Soil enzyme activities, the number of soil microorganisms, and soil nutrients were measured
in plantations of Chinese pine (Pinustabulaeformis), larch (Larix kaempferi), sharp tooth oak (Quercus aliena var. acuteserrata), Manchurian catalpa (Catalpa fargesii), and mixed plantations in the Qinling Mountains, China. Compared with pure plantations, the conifer-broad-leaved broadleaf
mixed plantations increased total N, available N, total P, available K, and organic matter in the forest soil; promoted the
activities of invertase and urease by 16.7% and 53.8%; and increased the total amount of soil microorganisms by 95.9% and
the number of bacteria by 104.5% (p<0.05). The correlations between soil enzymes, number of microorganisms, and soil nutrients were significant (p<0.05), and the correlations between the number of soil bacteria and basic nutrient prosperities (total N, available N, available
K, and organic matter (OM)) were significant or highly significant. The correlations between the number of soil actinomycetes,
and soil total N, available N, OM, and pH were also significant or highly significant. A suitable mixture of planted conifers
and broad-leaved species improves the quality and amount of soil nutrients, increases the number of soil microorganisms and
changes their redistribution. The change of soil enzymes and the number of soil microorganisms are indications of the change
tendency of soil nutrients.
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Translated from Journal of Northwest A&F University (Nat. Sci. Ed.), 2008, 36(10): 88–94 [译自: 西北农林科技大学学报] 相似文献
20.
Xiaoming Zhang Xinxiao Yu Sihong Wu Tianxing Wei Xuepei Zhang 《Frontiers of Forestry in China》2006,1(3):336-342
According to fixed-position data for 1985–2003 from nine runoff plots of Caijiachuan watershed which lies in Jixian County
of Shanxi Province in Loess area, this paper studied the relationship between vegetation and runoff and sediment production
in sloping lands in detail, which helps to provide scientific basis for vegetation re-construction and studies on environmental
transformation of water and sediment in watersheds of Loess area. Although, many study results testify that forest vegetation
has an important function in soil and water conservation and cutting runoff, the effect of vegetation on runoff and sediment
transmission is complicated, and this needs to be studied in depth. The results of the paper showed the following. Firstly,
the natural secondary forest performs better function of soil and water conservation than artificial Robinia pseudoacacia forest, and runoff and sediment produced in the former in individual rainfall were 65%–82% and 23%–92% of those produced
in the latter. At the same time, better correlative relationship between runoff and sediment production and rainfall and rainfall
intensity were testified by multiple regression, but the correlation decreased gradually with the increase of canopy density
of forest. Secondly, the difference of runoff and sediment production in several land use types was very distinct, and the
amount of runoff and sediment produced from Ostryopsis davidiana forest and natural secondary forest were the least, and runoff and sediment produced from in artificial Robinia pseudoacacia forest and Pinus tabulaeformis forest were 5-fold as much as those from O. davidiana forest. Besides, runoff and sediment produced in mixed planting of apple trees and crops were 16.14-fold and 2.96-fold than
those of O. davidiana forest, respectively, but the amount decreased obviously after high-standard soil preparation in the case of the former.
Thirdly, based on gray cognate analyses of factors affecting runoff and sediment production in sloping land, the factors of
stand canopy density and herb and litter biomass were the most significant ones, whose gray incidence degree exceeded 0.6.
Therefore, mixed forest with multi-layer stand structure and shrub forest should be developed in vegetation re-construction
of Loess area, which will help to increase coverage and litter thickness in order to cut down the runoff and sediment dramatically
in sloping land.
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Translated from Chinese Journal of Applied Ecology, 2005, 16(9): 1,613–1,617 [译自: 应用生态学报, 2005, 16(9): 1,613–1,617] 相似文献