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1.
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. __________ Translated from Chinese Journal of Ecology, 2007, 26(4): 509–514 [译自: 生态学杂志]  相似文献   

2.
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. __________ 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   

3.
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 = mpn. 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. __________ 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   

4.
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. __________ 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   

5.
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. __________ 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   

6.
The characteristics and actualities of ecological public welfare forests in South China are studied in this paper, including common and special management patterns. The restoration and reconstruction pattern of subtropical evergreen broad-leaved forests, zonal vegetation in the key eco-zone, and the transformation pattern of coniferous and broad-leaved mixed forests in the general eco-zone with multi-forms are discussed in detail. The authors also point out, based on ecological transformation and utilization, that ecological public welfare forests should be oriented to multiple benefit utilization to maintain sustainable management. __________ Translated from Journal of Nanjing Forestry University, 2007, 31(2): 97–100 [译自: 南京林业大学学报]  相似文献   

7.
Cyclobalanopsis glauca is a dominant species of evergreen broad-leaved forests in mainland China. This study compares the genetic variation of an artificially regenerated population with its donor population and two other wild populations, by using RAPD markers. A total of 74 clear, reproducible bands were scored for 12 RAPD primers; 72 were polymorphic (P = 97.3%). AMOVA revealed that most genetic variation was within populations and only 10.35% was among populations. Various measures indicated that there is no difference in genetic diversity between the planted and the original populations. ΦST between the planted offspring population and the donor population was larger than those between the planted and other two natural populations, indicating that artificial regeneration might lead to biased genetic composition, given that temporal differentiation is usually lower than spatial differentiation. This divergence may be due to unequal seed production among the maternal individuals and viability differences among seeds.  相似文献   

8.
The Mn, Zn and Cu contents of litter, soil fauna and soil in Pinus koraiensis and mixed broad-leaved forest in Liangshui Nature Reserve of Xiaoxing’an Mountains were analyzed in this paper, results showed that the tested microelement contents in the litter, soil fauna and soil followed the order: Mn>Zn>Cu, but varied with environmental components, for Mn the order is soil>litter>soil fauna, for Zn is soil fauna>litter and soil, and for Cu is soil fauna>soil>litter. The change range of the tested microelement contents in litter was larger in broad-leaved forest than those in coniferous forest. Different soil fauna differed in their microelementenrichment capability, the highest content of Mn, Zn and Cu existed in earthworm, centipede and diplopod, respectively. The contents of the tested microelements in soil fauna had significant correlations with their environmental background values, litter decomposition rate, food habit of soil fauna, and its absorbing selectively and enrichment to microelements. The microelements contained in 5–20 cm soil horizon were more than those in 0–5 cm humus layer, and their dynamics differed in various horizons. __________ Translated from Chinese Journal of Applied Ecology, 2007, 18(2): 277–282 [译自: 应用生态学报]  相似文献   

9.
Deciduous broad-leaved forests (DBF), Larix principis-rupprechtii (LF) and Pinus tabulaeformis plantations (PF) are three typical forest communities in the warm temperate zone of the Dongling Mountains. In this study, we used an indirect method, hemispheric photography, to measure and analyze the dynamics of leaf area index (LAI) and canopy openness of the three forest communities. The results show that the LAI values of DBF and LF increased gradually with plant growth and development. The highest LAI value appeared in August, while canopy openness changed inversely with LAI. The lowest value appeared in November. DBF maintained a higher LAI in August and had a more open canopy in November compared with LF. For PF, we observed little changes in the LAI and canopy openness which was attributed to the leaf retention of this evergreen species. However, a similar relation between LAI and canopy openness was found for the three forest communities: canopy openness varied inversely with LAI. The relation is exponential and significant. Therefore, canopy openness is a good indicator of LAI in forests. This result can be used to test the validity of the LAI based on remote sensing and to provide a reference for the study of the canopy heterogeneity and its effect. This also benefits modeling for fluxes of carbon, water and energy from the level of the stand to landscape. __________ Translated from Journal of Plant Ecology, 2007, 31(3): 431–436 [译自: 植物生态学报]  相似文献   

10.
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. __________ 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   

11.
The random amplified polymorphic DNA (RAPD) technique was used to evaluate the genetic diversity and population structure of 91 genets from four wild populations of Betula luminifera at different elevations in the National Nature Reserve of theWuyi Mountain, Fujian Province, China. Eighteen random primers (from 139 primers) produced a total of 199 scorable amplified fragments, of which 174 (87.44%) were polymorphic across all individuals. The genetic diversities of B. luminifera at the population level and species level were PPL = 60.05%, h = 0.2242, I = 0.3181 and PPL = 87.44%, h = 0.3442, I = 0.4899, respectively. The value of differentiation (G st= 0.3486) and analysis of molecular variance (AMOVA) indicated that there was a relatively high genetic differentiation among populations, and about one-third of the genetic variation occurred among populations. Pearson correlation analysis further revealed that the genetic diversity within populations had significant or very significant correlation with the elevation, climatic factors (annual average temperature and annual precipitation) and soil nutrient factors (total nitrogen, C/N ratio and organic matter). Mantel tests show that there was a significant correlation between the genetic distances among populations and the distance of elevation, and the divergence of soil nutrient factors. The results of the present study suggested that the relatively high genetic differentiation among populations of B. luminifera at different elevations might be caused by ecological factors and gene flow. __________ Translated from Scientia Silvae Sinicae, 2008, 44(3): 50–55 [译自: 林业科学]  相似文献   

12.
[Objective]To study the leaf calorific value of different forest types.[Method]This study focused on four common forest types widely distributed across China, including boreal coniferous forest, warm temperate deciduous broad-leaved forest, subtropical evergreen broad-leaved forest, and tropical monsoon forest. The leaf calorific values of 175 dominant (or common) tree species were measured. The leaf calorific value characteristics of the trees found in the different forest types were analyzed, and the primary factors affecting leaf calorific value were investigated, including leaf morphological traits, nutrient elements, climate, and soil traits. [Result]The results showed that in these forest types, the leaf calorific values ranged from 14.84 to 21.98 KJ·g-1, with an overall mean of 19.06 KJ·g-1. The presence of organisms appeared to affect the leaf calorific value, which differed among forest types as follows: coniferous trees > broadleaf trees or evergreen trees > deciduous trees. [Conclusion]The latitudinal pattern of tree leaf calorific value, ordered from north to south, is as follows: warm temperate deciduous broad-leaved forest > subtropical evergreen broad-leaved forest > tropical mountain rainforest. The mean leaf calorific value of boreal coniferous forest was slightly lower than those of warm temperate deciduous broad-leaved forest and subtropical evergreen broad-leaved forest. The leaf calorific values were significantly correlated with leaf carbon content (R2= 0.89, P<0.001). A multiple regression equation was established to describe the relationships among leaf calorific value, leaf carbon content, leaf nitrogen content, and leaf thickness.  相似文献   

13.
Genetic relationships were studied among 23 isolates of Sphaeropsis sapinea collected from China, the United States, England, South Africa and Chile by using a random amplification of a polymorphic DNA (RAPD) analytical method. One hundred and 35 DNA fragments were amplified with 12 random primers by a polymerase chain reaction PCR technique and 96.3% were polymorphic. The genetic dendrogram based on RAPD analysis showed that the S. sapinea isolates could be divided into three types. Isolate CWS41 from Chile was separated genetically as the first type that was different from other isolates and isolates F2 and J2 from China comprised the second group. The third RAPD group accommodated other isolates including the B morphotype isolate CWS43 from the United States. __________ Translated from Journal of Nanjing Forestry University, 2006, 30(1): 13–16 [译自: 南京林业大学学报]  相似文献   

14.
以思茅松人工林中龄林、近熟林和过熟林及附近区域思茅松天然林和常绿阔叶林为研究对象,探讨造林对思茅松人工林土壤有机碳和氮储量大小与空间分布的影响。结果表明:各林地类型土壤有机碳、氮含量与C:N随着土层厚度增加而减少,过熟林土壤有机碳和氮含量随土层加深则显著高于其它林地类型,近熟林土壤表层有机碳和氮含量显著低于中龄林和过熟林。思茅松人工林乔木层碳储量随林龄增大而增加,过熟林乔木层碳储量最高。造林对思茅松人工林土壤氮储量的影响不显著,而土壤有机碳储量随林龄增大先减少后增加至过熟林恢复至常绿阔叶林和思茅松天然林水平,土壤有机碳与氮储量随土层加深而减少。与常绿阔叶林和思茅松天然林相比,思茅松人工林的中龄林与过熟林土壤有机碳和氮储量的年变化量高于近熟林,近熟林年变化量呈净减少;在思茅松天然林中,人工更新与在常绿阔叶林中造林相比,思茅松人工林可以累积更多的土壤有机碳和氮储量。此外,土壤含水量越大,土壤有机碳储量则越高。  相似文献   

15.
Seedling emergence and initial survival were compared for two evergreen broad-leaved species, Quercus glauca and Symplocos prunifolia. The relationships between the two seedling dynamics variables and environmental factors for the two species were also investigated. The number of seedlings that emerged in the study period was larger for S. prunifolia than for Q. glauca, while the survival rate was lower for S. prunifolia, presumably due to the closed canopy of this site. Models were selected for each species to determine the combination of variables explaining the most variation in emergence and survival of seedlings. The model selected for seedling emergence of Q. glauca showed that more seedlings emerged in lower hillslope positions and where the canopy in winter was more open. The model selected for S. prunifolia showed that fewer seedlings emerged on steeper slopes and that more emerged under a more open canopy in winter. With respect to seedling survival, models with only the proportion of open canopy in summer were selected for both species. These models showed that the survival rate was higher where the canopy in summer was more open. This is to be expected as both species are regarded as pioneer or mid-successional species. Q. glauca seemed to have the ability to persist as a dominant in the secondary forest at this site for longer than S. prunifolia due to the former’s better seedling survival rates and the rarity of climax species such as Castanopsis cuspidata.  相似文献   

16.
Precipitation chemistry was monitored in two different types of forests (mixed Pinus tabulaeformis and Quercus variabilis forest and pure Q. variabilis forest) in Jiufeng National Forest Park, in western Beijing. Results showed that the pH value of precipitation ranged between 6.13 and 6.97 and no acid rain appeared; the mean electrical conductivity (EC) was 0.18 mS/cm and mean total suspended particles (TSP) was 44.02 mg/L, but these values changed significantly with different amounts of stem-flow. Acidification occurred in the stem-flow to different extents: that of P. tabulaeformis > Q. variabilis. The mean EC value of stem-flow in P. tabulaeformis in the mixed forest was 1.00 mS/cm, which was 5.88 times as high as that of precipitation outside the forest. EC values of Q. variabilis in pure and mixed forests show little difference, 0.34 and 0.30 mS/cm, respectively and were 2.00 and 1.76 times higher than that of precipitation. During the summer, EC values of stem-flow of P. tabulaeformis decreased over time and with an increase in the amount of precipitation. The mean TSP of stem-flow in mixed forest was 116.95 mg/L, but 87.14 mg/L in the pure forest, which were 72.93 and 43.12 mg/L higher than that of precipitation. __________ Translated from Journal of Beijing Forestry University, 2005, 27(1): 88–91 [译自: 北京林业大学学报]  相似文献   

17.
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. __________ 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   

18.
贵州麻江森林健康经营项目示范区森林植被类型初步分析   总被引:1,自引:0,他引:1  
项目示范区的森林属于次生林,调查分析结果表明该示范区的植被类型比较齐全,有西南米槠-黄连木-锈鳞苔草常绿阔叶林、漆树+美脉琼楠+大花枇杷-蚊母树+高丛珍珠梅+鸢尾常绿落叶阔叶林、白栎+麻栎+枫香-芒箕落叶阔叶林、马尾松+白栎+枫香+油桐-白栎针阔混交林、马尾松和杉木针叶林、白栎-金星厥灌丛.  相似文献   

19.
One 50 m × 50 m standard plot was sampled in a natural forest of Populus euphratica in Awati County, situated at the edge of the Tarim Basin, Xinjiang Uygur Autonomous Region, China. The field investigation was conducted with a contiguous grid quadrate method. By means of a test of variance/mean value ratio, aggregation intensity index and theoretical distribution models, the spatial distribution pattern and the dynamics of primary populations in P. euphratica forest were studied. The results showed that the spatial distribution pattern of two dominant arbor populations conformed to clumped distribution. The aggregation intensity of the P. euphratica population was higher than that of P. pruinosa population. The spatial distribution pattern of two companion plant populations in the shrub layer also conformed to clump type, though the aggregation intensity of Tamarix chinensis was higher. In the herb layer, the distribution patterns of Glycyrrhiza uralensis and Asparagus persicus conformed respectively to a clumped pattern and a random pattern. The results of a Taylor power method test and Iwao’s regression model also verified that both P. euphratica and P. pruinosa populations belong to a clumped pattern. Although the distribution pattern of P. pruinosa population at different development stages all belonged to a clumped distribution pattern, the aggregation intensity dropped gradually along with age development. The distribution patterns of the P. euphratica population at different development stages changed from random type to clumped type, and further to random type. The differences in spatial distribution patterns of different populations at different development stages were related not only to ecological and biological characteristics of each species in the communities in the light of competitive exclusion principle among the populations, but were also closely related to the habitats in which the species lived in. __________ Translated from Journal of Southwest Forestry College, 2007, 27(2): 1–5 [译自: 西南林学院学报]  相似文献   

20.
We have examined the pattern of random amplified polymorphic DNA (RAPD) variation among six populations of Crataegus monogyna from northern Italy, extending over an area of about 20,000 km2. The aim was to evaluate local differentiation in relation to geographical distance. Of the 73 loci analysed, 65 were polymorphic, and there were no bands at complete fixation at the population level. The mean genetic diversity was 0.291, with the values for individual populations ranging between 0.252 and 0.333. According to the analysis of molecular variance most of the genetic variation was found within populations (about 80%), with a significant proportion being attributable to genetic differences between populations. No evidence for isolation by distance was found in the set of populations sampled. The efficacy of RAPD markers in analysing genetic variation, and the contribution of the results in terms of the preservation of biodiversity and defining the most appropriate strategies for collecting forest reproductive material, are discussed.  相似文献   

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