• 中国中文核心期刊
  • 中国科学引文数据库(CSCD)核心库来源期刊
  • 中国科技论文统计源期刊(CJCR)
  • 第二届国家期刊奖提名奖

2012 Vol. 25, No. 5

Display Method:
Quantitative Study on the Drive Factors of Wetland Change in Three Rivers' Source Area
CHEN Yong-fu, LIU Hua, ZOU Wen-tao, ZHANG Huai-qing
2012, 25(5): 545-550.
Abstract:
The TM remote sensing data of 1990, 1997 and 2007, 652 sample plots data, climate and social economy data of 1990 to 2007, the wetland distribution map, the vegetation distribution and the topographic maps was used to define the main factors driving wetland type change, so as to establish drive model of wetland change by partial correlation analysis. The results showed that the main drive factors of river and flood land change were annual average temperature, annual evaporation, annual relative humidity and annual milk production; the main drive factors of lake change were annual evaporation, annual relative humidity, annual population and annual milk production; the main drive factors of marsh and total wetland change were annual rainfall, annual population and annual average personal income. The Judge coefficient R2 of drive model were 0.830 1, 0.757 2, 0.967 5, 0.833 3, and 0.967 9. Through F examination, the influence of independent variable to random variable was notable.
Extraction of Total RNA from Horned-gall and the Cloning of ACTIN Gene Fragment
RUAN Zhen-yuan, CHEN Xiao-ming, YANG Zi-xiang
2012, 25(5): 551-557.
Abstract:
The extraction of total RNA from the horned-galls of Rhus chinensis is the basis of the researches on the molecular mechanism of gall formation. Due to high levels of polyphenol and polysaccharides, the modified CTAB method depositing with isopropanol was selected from different kinds of kits and other improved methods. It is a simple, economic and effective method for the extraction of total RNA, and the yield could get 60.16 μg/100 mg. Reverse transcription was conducted on the total RNA extracted by CTAB-isopropanol method, and a 934 bp cDNA sequence of ACTIN gene coding a protein of 311 amino acids was obtained. Homology comparison showed that it shared 95% nucleotide sequence homology with Mangifera indica and over 86% amino acid sequence similarity with actins in other species. The results laid basis for molecular researches of Rhus chinensis and other aphid induced galls.
Using Segmented Modeling Approach to Construct Tree Volume and Biomass Equations for Larch in Northeastern China
DANG Yong-feng, WANG Xue-jun, ZENG Wei-sheng
2012, 25(5): 558-563.
Abstract:
Based on the tree volume and above-ground biomass data of larch (Larix spp.) in northeastern China, the compatible tree volume and above-ground biomass equations and biomass conversion functions were constructed using the error-in-variable simultaneous equations and segmented modeling approach. The results show that: (i) The error-in-variable simultaneous equations can ensure the compatibility of tree volume and biomass estimates, and the segmented modeling approach can resolve the problem of systematically biased estimation in small diameter classes for commonly-used tree volume and biomass equations; (ii) Through the one variable-based segmented equations, both the mean prediction errors (MPEs) of tree volume and above-ground biomass estimates for the whole data are less than 5%; and through the two variables-based segmented equations, the MPE of tree biomass estimates is about 4%, and the MPEs of tree volume estimates is less than 3%.
Research on Geological Provenances Variation and Selection of Parakmeria latungensis
LIU Jun, JIANG Jing-min, LIU Zhao-xi, LUAN Qi-fu, SUN Hong-gang, SHAO Wen-hao, ZHANG Jian-zhong
2012, 25(5): 564-568.
Abstract:
The growth traits of seed, seedling and young forest of 14 provenances of Parakmeria latungensis were investigated and analyzed. The results showed that the differences in seed weight, seedling height, basal diameter, leaf length and leaf width among provenances were extremely significant, and significant difference in afforestation preservation rate was also found among provenances. The provenances with higher preservation rate were from the northern source, such as Longquan provenance from Zhejiang Province. But provenances from the southern source such as Jianfengling provenance from Hainan Province showed the lower preservation rate. The differences in main growth traits were significant among provenances for young forests, such as 4-year-old tree height, five-year-old tree height and diameter at breast height, 6-year-old tree height and diameter at breast height. The broad heritability of these five traits was between 0.855 and 0.930, which indicated that phenotypic differences of the main growth traits were controlled mainly by genetic factors. Tree height and diameter at breast height were negatively correlated with the latitude, indicating that the decreasing trend of tree growth with increasing latitude of provenances. Tree height and diameter at breast height of young forest were positive related to the longitude, and positively related to the latitude. According to the trial results of the young provenance forest, three superior provenances, Longquan in Zhejiang Province, Shunchang in Fujian Province and Xinning in Hunan Province, were selected. The provenance source region of Parakmeria latungensis was divided into three subregions: the western source subregion, the eastern source subregion and the southern source subregion.
Physiological and Biochemical Response to Drought Stress in Seedling Stages and Drought-Resistance Evaluation of Sweet Tamarind Varieties
ZHAO Yi-he, LI Jian-bin, YANG Shi-yu, CHEN Shu-ying, XI Cong-fang, LI Ti-chu
2012, 25(5): 569-575.
Abstract:
The physiological and biochemical indexes such as protoplasmic membrane penetrability (PMP), malondialdehyde (MDA) content, osmoticum content, activities of protective enzymes, leaf relative water content (LRWC) and chlorophyll content (CHLC) in leaves of three Sweet Tamarind varieties of PRAKAYTONG, SRITONG, and SRITONGBAO were measured under constantly drought stress, and then the drought resistance was evaluated by drought-resistant coefficients and subordinate function. The result showed that with the development of constantly drought stress, the PMP, MDA content, proline content, soluble sugar content and soluble protein content were increased, the activities of superoxide dismutase and peroxidase increased in the beginning and decreased at last, and the LRWC and CHLC decreased in leaves of the three kinds of Sweet Tamarind. The comprehensive evaluation result by drought-resistant coefficients and subordinate function methods showed that the order of drought resistance was PRAKAYTONG > SRITONGBAO > SRITONG.
Analyzing Climate Suitability of Pinus yunnanensis Based on Kira’s Indices
CHEN Fei, WANG Jian-min, CHEN Xiao-ming, SUN Bao-gang, YANG Zi-xiang, DUAN Zhao-yao
2012, 25(5): 576-581.
Abstract:
Based on the meteorological data of Yunnan Province and the space distribution data of Pinus yunnanensis, with Kira's indices, and by using statistical methods and GIS software, the spatiotemporal change characteristics of climate resources and the suitable area's changes of P. yunnanensis were analyzed. The results indicated that the mean value of P. Yunnanensis' warmth index was 122.9 ℃·month, ranging from 32.1-204.3 ℃·month, and it's optimum range was 86.1-160.0 ℃·month. The interannual variation curve of Warmth Index (WI) in Yunnan Province was significantly elevated, from 121.30 ℃·month (1970) to 133.57 ℃·month (2002), and the interannual variation curve of Humidity Index (HI) followed a downward trend, from 10.97 mm·(℃·month)-1 (1970) to 8.92 mm·(℃·month)-1 (2002). The WI fluctuation was more significant than HI fluctuation. The maximum value occurred during 1998 (136.63 ℃·month), and the minimum value for the 1976 (117.13 ℃·month). However, both the maximum and minimum values belong to the optimal range of P. yunnanensis. Under the condition of climate changing in the future, P. yunnanensis will be centralized in areas of middle Yunnan, but the distribution area will change. The north distributing limitation will not move obviously but the south boundary will atrophy obviously, and the suitable area will decrease stage by stage.
Study on Biomass and Productivity of Picea likiangensis var. linzhiensis Forest in Nanyigou of Tibet
FANG Jiang-ping
2012, 25(5): 582-589.
Abstract:
Based on the data collected from a standard permanent plot of a primary Picea likiangensis var. linzhiensis forest in Milin Nanyigou in Tibet, the amount and distribution of biomass and productivity were studied by investigating and sample tree harvesting method. The results showed that the total vegetation biomass of P. likiangensis var. linzhiensis forest was 367.49 t·hm-2, of which overstory trees contributed the large proportion (75.28%) and amounted to 276.64 t·hm-2. The litter layer ranked the second with the biomass amount of 40.65 t·hm-2, accounted for 11.06% of the total biomass. In the overstory layer, the biomass was allocated as 201.23 t·hm-2 (69.32%) for trunk, 25.53 t·hm-2 (8.79%) for bark, 17.80 t·hm-2 (6.13%) for branch, 3.33 t·hm-2 (1.15%) for leaf, and 42.87 t·hm-2 (14.61%) for root. With the growth of trees, the biomass proportion of trunk and bark increased, while that of the branch and leaf decreased. The total vegetation productivity was 10.65 t·hm-2·a-1, of which overstory trees contributed a large proportion (46.94%) and amounted to 5.00 t·hm-2·a-1. The litter layer ranked the second with an amount of 3.40 t·hm-2·a-1 that accounted for 31.94% of the total proportion. In the overstory layer, the proportion was allocated as 2.58 t·hm-2·a-1 for trunk, 0.89 t·hm-2·a-1 for branch, 0.67 t·hm-2·a-1 for leaf, 0.54 t·hm-2·a-1 for root and 0.33 t·hm-2·a-1 for bark.
Characteristics of Phosphorus Utilization in Families of Toona ciliata var. pubescens
KONG Chao, LIU Jun, JIANG Jing-min, LI Yan-jie
2012, 25(5): 590-596.
Abstract:
Soil culture at 4 phosphorus levels was conducted to illustrate characteristics of phosphorus utilization in 8 families of Toona ciliata var. pubescens with different responses to phosphorus supply. The results indicated that the seedlings were very sensitive to phosphorus supply, and the biomass accumulation of those with minor phosphorus supply were 3-19 times those in natural red soil. At different phosphorus levels, great differences in productivity were found among families. Under low phosphorus stress, the highest ones were 7 times those of the lowest, and under high phosphorus level, the highest ones were 2.6 times those of the lowest. P absorption efficiency was the main reason making differences of dry matter accumulation among families. The dry matter accumulation has a high and positive correlation to height and basal diameter of seedlings and root parameters. The root length, root volume, root surface, and the number of fibrous roots were selected as the special characteristics of families that can endure low phosphorus.
Water Use Strategy of Salix cheilophila Stands with Different Ages in Gonghe Basin, Qinghai Province
LIU Li-ying, JIA Zhi-qing, ZHU Ya-juan, LI Hong, YANG De-fu, WEI Deng-xian, ZHAO Xue-bin
2012, 25(5): 597-603.
Abstract:
Salix cheilophila is one of the main shrub species for afforestation in Alpine Sandland of Gonghe Basin, Qinghai Province. Stable isotope technique was used to test the δD and δ18O value of rain, well water, branch xylem and different soil depth of 5-,9- and 25-year-old S. cheilophila plantation, and then the differences of main water source among the three S. cheilophila stands with different ages were analyzed. Also, the δ13C value of leaves was tested to evaluate the water use efficiency (WUE) of the S. cheilophila stands. Comparison of δD and δ18O showed that 5-year-old S. cheilophila used the water in 10-50 cm soil infiltrated from rainwater; 9-year-old S. cheilophila consumed relatively deep soil water, including 20 cm infiltrated from rainwater and 30-50, 150 cm replenished by ground water; and 25-year-old S. cheilophila used 10-20 cm soil water infiltrated from rainwater and 50 cm soil water replenished by ground water. The difference of leaf δ13C value among 5-, 9- and 25-year-old S. cheilophila stands was significant; 5-year-old S. cheilophila has exclusively high WUE, whereas that of 9-year-old and 25-year-old stands were similar. The water source and WUE suggest that 9-25 years old S. cheilophila was in steady period.
Comparison of Vegetative Compatibility Diversity of Cryphonectria parasitica from Wild and Cultivated Chestnut and Molecular Detection of Mating-type of the Pathogens from Wild Chestnut
PAN Qi, ZHANG Guo-zhen, HE Wei, FEI Song-lin, CHEN Yu-chao, ZHANG Hai-wang
2012, 25(5): 604-611.
Abstract:
The incidence of chestnut blight caused by Cryphonectria parasitica in the regions of Beijing, Hubei and Shaanxi was investigated and the pathogen strains collected from these regions were used to detect their vegetative compatibility groups (VCGs). The results showed that the incidence of chestnut blight in Beijing and Shaanxi, varying according to different site conditions, was higher than that in Hubei. The Shannon-Wiener's diversity indexes of the VCGs of strains collected from Hubei and Shaanxi were statistically higher than that of strains from Beijing, whereas no statistical difference between the indexes of Shaanxi and Hubei. In addition, the mating-types of the representative strains selected randomly from Shaanxi and Hubei populations were detected by means of primary and nested PCR with specific primers. The results showed that both populations had two mating-types. Meanwhile, the strains with two mating-types in a single strain were detected as well, showing higher proportion in Shaanxi population than in Hubei population.
Effects of Fruit Maturity and Compost on Oil Yield and Quality of Camellia reticulate
HUANG Jia-cong, KAN Huan, WAN Xiao-jun, YANG Kai-bao
2012, 25(5): 612-615.
Abstract:
Fruit collection and compost trials were conducted, including four combination treatments of two fruit maturity (eighty percent matured and almost fully matured) with the fruit composted or not, by using 38 superior trees of Camellia reticulata. The oil yield and quality were tested and compared for each tree and treatment. The results showed that there existed significant differences in oil yield and quality among the four treatments, collecting the eighty percent matured fruits led to heavy loss of oil yield, and the ratio of oil in kernel, seed and fruit declined by 11.0, 18.2 and 31.7 percent, respectively, while the oil acid value also deceased by 10.5 percent which was good for oil storage. After compost treatment, the matured fruits were seen that the ratio of oil in kernel declined by 4.5 percent as well as oil acid value increased by 7.3 percent. It was thus concluded that fruit should be collected when matured and seed-husking should be done as soon as possible after fruit collection. These findings will provide technical support for fruit collection and treatment of C. reticulata.
Establishment of PCR Assay for Detecting of Lymantria dispar Multiple-embedded Nucleopolyhedrovirus (LdMNPV)
TAO Jing, HAN Chong-xuan, ZHANG Yong-an, WANG Yu-zhu, QU Liang-jian, WANG Qing-hua
2012, 25(5): 616-619.
Abstract:
A technical architecture used for the microdetermination of Lymantria dispar multiple-embedded nucleopolyhedrovirus was set up. Based on egt gene of LdMNPV, a pair of primers was designed with the sensitivity of 1fg·mL-1 DNA. By using this pair of primers, the partial sequences of egt gene were amplified from the eggs, larvae and pupae of the infected L. dispar, which verified the feasibility of this method. The partial sequences of egt gene were also amplified from the polyhedron suspension and the minimum amount of detection could be as low as 5 OBs·mL-1 of polyhedron. Morphology research indicated that the surface of a few of polyhedrons was rough pitted and released virions. It could be a reason why the target DNA fragment could be amplified from the virus suspension. So in the detection of LdMNPV, suspension after trituration, filtration and centrifugalism can be used as template.
Control Techniques of Melanotus cribricollis (Coleoptera: Elateridae)
SHU Jin-ping, TENG Ying, CHEN Wen-qiang, SHI Jian, LIU Jian, XU Tian-sen, WANG Hao-jie
2012, 25(5): 620-625.
Abstract:
Melanotus cribricollis is one of the most important pest insects that damage bamboo shoots in South China, and no report was found in the control techniques of this insect. The effect of three control methods, shoot-removing, light trapping and insecticidal control against M.cribricollis in fields were studied. The results showed that all the three methods could reduce the damage and density of wireworms significantly, and the insecticidal control was the most effective. The control efficiency of shoot-removing against bamboo wireworms was (22.76±3.90)% in three years; 1 143.8±318.7 adults of M.cribricollis could be caught per light per year, and the damage percent of shoots dropped from (56.05±2.83)% to (39.207±2.83)% with light trapping in 6 years. The insecticide blend of 5% phoxim and 3% chlorpyriphos showed to be effective against M. cribricollis, and the damage percent of shoots dropped from (69.62±5.36)% to (21.17±7.65)% in 3 years.
The Role of Increased Precipitation in Promoting Branch and Leaf Growth of Nitraria tangutorum
ZHU Ya-juan, JIA Zi-yi, WU Bo, LU Qi, YAO Bin
2012, 25(5): 626-631.
Abstract:
A rain-increasing test with different ratios of precipitation (0%, 25%, 50%, 75%, 100%) were conducted on natural Nitraria tangutorum shrubland based on the mean annual precipitations at the northeast margin of Ulan Buh Desert (Dengkou of Inner Mongolia, 145 mm) and southeast margin of Badan Jaran Desert (Minqin of Gansu Province, 115 mm). The results showed that the more the precipitation increased, the more the change of morphological traits of N.tangutorum. The effect of 100% precipitation-increasing on morphological traits of N.tangutorum was significant both at Dengkou and Minqin: including length, diameter and dry biomass of marked branch, but not including the amount of mature leaf or new leaf. Fresh biomass and dry biomass of branch and leaf of N.tangutorum were also enhanced by increased precipitation in September both at Dengkou and Minqin. More increased precipitation could promote branch growth of N.tangutorum in more arid area. The biomass of N.tangutorum was enhanced by 50% increased precipitation in late summer in Dengkou. However, it was enhanced by 75% increased precipitation in late summer in Minqin.
Comparative Study on Germination of Bretschneidara sinensis Seeds Treated with Solution Extracted from Forest Litter and Other Methods
MA Dong-xue, LIU Ren-lin
2012, 25(5): 632-637.
Abstract:
Experiments of germination of Bretschneidara sinensis seeds were conducted by the methods of field and indoor experiments by which the seeds were soaked in different solutions extracted from late-leaves forest litter, or treated with different growth hormones, or treated under different temperatures. The results are as follows: (1)Based on comparison, there were differences in germination rate among different solutions extracted from forest litter, but it was not so obvious. The highest percentage (69.2%) of germination was made by distilled water. The order of germination rate is distilled water>solution extracted from forest litter of Bretschneidara sinensis communities>solution extracted from forest litter of Castanopsis fabri communities. (2)According to the results of all the experiments, the solution of 200 mg·L-1 GA3 made the highest germination rate (80.0%) in which the seeds were soaked for 12 h. (3)The germination rate of nursery was very close to the experiment result made in indoor, but the highest percentage (70.4%) of germination is made by the alcohol solution extracted from forest litter of Bretschneidara sinensis communities. (4) Analysis of experiments showed that the optimal temperature for seed germination was 20℃ 25℃ and the highest percentage of seeds germination appeared at the 10th day to 26th day; besides, the seed germinating continued for 32 days. (5) The rate of seed decay was the highest at the time 7th-14th day during germination, and the seed decay would be postponed with the temperature rising,but the germination rate would be also lower.
Effect of Stem Bending Angle on Formative Tissue During Wood Formation of Pinus koraiensis
SHI Jiang-tao, SUN Qing-feng, XING Dong, LIU Yi-xing, LI Jian
2012, 25(5): 638-643.
Abstract:
In order to study the effect of stem inclination angle on compression cell wall formation, seven-year-old Pinus koraiensis was chosen for different mechanical bend angle treatments. The height and diameter at breast height, lignin and cellulose content, FTIR and polar metabolites were measured. The results showed that high growth rate was obviously restrained by inclination angle but diameter growth showed no marked effect. The lignin content increased and the cellulose content decreased in bended samples, and all showed significantly effected by inclination angle. FTIR also showed distinctly difference among different angles. The metabolites like carbohydrate, lipids, amino acids, N-compounds and organic acids showed different varying patterns. Therefore, the typical compression wood was formed when the stem was bended by 50° in P. koraiensis. The variation pattern of metabolites was in accord with macroscopic properties in newly formed wood. The changes of metabolites reflected the response mechanism in stress of tree.
Introduction and Early Evaluation of Species and Provenances of Spruce
LI Qing-fen, WANG Jun-hui, ZHANG Jian-hua, ZHANG Song-zhi, MA Jian-wei, YANG Hai-yu
2012, 25(5): 644-650.
Abstract:
Early evaluation experiments in twenty-four provenances of Picea abies, P.sitchensis, P. glauca, P.mariana, P.likiangensis (Franch) Pritz var. balfouriana (Rehd.et Wils.) Hillier ex Slavin and P.crassifolia were carried out. The results showed that there existed very significant or significant differences in most of growth and lateral branch traits among species and provenances of young forests, and the average variance component of species and provenances accounted for 32.47% and 23.97% of total variance component respectively, all of which indicated that there were high genetic variations among species and provenances. Moreover, there was a extremely and obviously positive relationship between growth and lateral branch characteristics by correlation analysis, especially the plant height and lateral branch traits, their average value of correlation coefficients was 0.825 9. As a result of this research, six excellent provenances of spruce were selected tentatively on the basis of plant height. All of these superior provenances had distinct predominance in growth, their average values of plant height, total number of lateral branches and the number of newest lateral branches were 117.07 cm, 57.75 and 12.46, respectively, which were 48.54%, 56.46% and 63.30% higher than the overall means of contrast spruce provenances.
Effects of Cadmium Stress on Leaf Photosynthesis and Dry Matter Allocation of Populus×euramericana (Dode)Guineir cv.‘Neva’
LIN Xiao-hui, DUAN Ai-guo, HE Cai-yun, ZHANG Jian-guo
2012, 25(5): 651-656.
Abstract:
The effects of cadmium stress on leaf photosynthesis and dry matter allocation for one-year-old seedlings of Populus × euramericana(Dode)Guineir cv.‘Neva’ were studied through potted cultivation. The results showed that in the early 10 days of cadmium stress, the net photosynthetic rates (Pn) of seedlings of four trial treatments greatly decreased at first followed by relatively slow various increase, relative to contrast, the treatments of 50, 100, 150 and 200 mg·kg-1 respectively had the maximum reduction of 17.1%, 17.8%,23.9%, and 24.7%. The higher the concentration of cadmium stress was, the bigger the descending depth was. The main factor that caused the descending of Pn was the occurrence of photosynthesis restriction induced by stoma restriction. At the stage of 10-40 d after treatment, different cadmium concentration treatment had no significant difference. After treatment time arrived at 60 d and 80 d, 200 mg·kg-1 cadmium stress had significant effect on Pn, the others didn’t arrive at significant levels. The cadmium concentration of 150 mg·kg-1 might be the key threshold for photosynthesis of P. × euramericana(Dode)Guineir cv.‘Neva’. The stem allocation ratio of P. × euramericana(Dode)Guineir cv.‘Neva’ seedlings increased with the increasing cadmium concentration, while the root allocation ratio decreased with the increasing cadmium concentration, the treatment of 200 mg·kg-1 could significantly decrease the root-shoot ratio of seedlings, and greatly baffle the growth of roots.
Growth Traits of One-Year-Old Catalpa bungei Clones in Seedling Stage
MA Wen-jun, ZHANG Shou-gong, WANG Jun-hui, ZHANG Jian-guo, ZHAO Kun
2012, 25(5): 657-663.
Abstract:
In order to study the growth traits of Catalpa bungei clones in various growth periods during the nursery stage so as to provide a theoretical basis for genetic improvement, the authors matched the height and diameter in nursery stage by Logistic equation. The results showed that the mean height of clones was 325.19 cm, with the range of 253.48-402.88 cm, the mean basal diameter of clones was 4.29 cm, with the range of 3.61-5.05 cm. The height increment could be divided into two stage, i.e. the early-growing period and the fast-growing period, while the basal diameter increment could be divided into three stage, i.e. the early-growing period, the fast-growing period and the late-growing period. The beginning of fast-growing period, the end of fast-growing period, the duration of fast-growing period, and the daily mean height increment in fast-growing period were May 26-July 2, September 11-October 15, 72-128 days, and 1.70-2.88 cm, while that for basal diameter increment were May 9-June 5, August 23-October 3, 95-138 days, and 0.021-0.032 cm. The variation of traits in fast-growing period was more significant. The height and basal diameter were significantly correlated to their increments in early-growing period (0.744, 0.928), fast-growing period (0.965, 0.804), and their daily mean increment in fast-growing period (0.733, 0.811).
Spatial Variability of Soil DNA in China Fir and Masson Pine Mixed Forest in Three Gorger Reservoir Areas
LIN Ying-hua, WANG Lai-fa, LU Ping, TIAN Xiao-kun, XIAO Wen-fa
2012, 25(5): 664-669.
Abstract:
Soil samples were collected to a depth of 20 cm using a 3.0 m×3.0 m grid in 900 m2(30.0 m×30.0 m) plots for analysis of spatial patterns of soil in undisturbed area of China fir (Cunninghamia lanceolata) and Masson pine(Pinus massoniana) mixed forest in the Three Gorger Reservoir Areas. The investigation data showed that the average of soil DNA content was 922.71 μg·g-1 water-free soil, the maximal value was 6 761.30 μg·g-1 water-free soil, and the less value 58.52 μg·g-1 water-free soil. The geostatistical analysis indicated that the spatial distribution characteristic was not obviously reflected by the liner graphs while samples were randomly distribution and independent each other. The separation distance among samples was related to precision of soil DNA content, the effects of non-structure factors (environment factors, disturbed factors) on spatial correlation structure would disappeared due to the separation distance in excess of 18.84 m, and the spatial correlation of soil DNA faded down in plots. Spatial variability in soil DNA in the region was mostly contributed by the influencing factors including soil nitrogen, soil organic matter and content of soil water.
Evaluation for the Growth Regularity of Progenies from Yingde Loblolly Pine Seed Orchard in North Guangdong
LIU Chun-xin, LIU Tian-yi, HUANG Shao-wei, LUO Rui, YANG Hui-xiao, WANG Ai-ping
2012, 25(5): 670-676.
Abstract:
Trials of 16-26 years old progenies from Yingde Loblolly Pine Seed Orchard were investigated by sample plot investigation. The trial fields were located at Yingde Loblolly Pine Seed Orchard, Yingde Forest Research Institute, Jiuqushui Forest Farm of Wengyuan County, Shaoguan Forest Farm and Renhua Forest Research Institute respectively. The growth process and performance level were studied by stem analysis based on average trees. Compared with that of local Masson pine (Pinus massoniana), the seedlots of loblolly pine (Pinus taeda) from Hubei and the seedlot of slash pine (P. elliottii) from Taishan Slash Pine Seed Orchard, the growth potential of progenies from Yingde Loblolly Pine Seed Orchard in North Guangdong was comprehensively evaluated. The results are as follows: The fast-growing period of height for the progenies from Yingde Loblolly Pine Seed Orchard began at the age of 3 and lasted for five to nine years. For diameter at breast-height (DBH) it began at the age of 5 and lasted for five to eight years. The fast-growing period for volume in Yingde Loblolly Pine Seed Orchard began at the age of 10 and lasted to 25 years old, while it began at the age of 10 both in Yingde Forest Research Institute and Jiuqushui Forest Farm, and at the age of 12 both in Shaoguan Forest Farm and Renhua Forest Research Institute. The progenies from Yingde Loblolly Pine Seed Orchard performed well generally in North Guangdong. Shaoguan and Renhua were suitable for the cultivation of large-dimension timber with the rotation longer than 25 years. In order to cultivate large-dimension timber, suitable fertilizer shall be used when the DBH growth reaches the fast-growing period, and thinning operation shall be conducted when the mean annual increment for DBH reaches the maximum.