2008 Vol. 25, No. 4
2008, 25(4): 405-410.
Abstract:
This research was designed to build a three dimensional（3D） background database for forest fire prevention. A new method using MapX （a coordinate transformation library） and OPEN Graphics Language （OpenGL） along with spatial information，data fusion，and 3D modeling technologies was developed to analyze features of a 3D background database. Digital Elevation Model（DEM） altitude data and OpenGL texture mapping were integrated with remote sensing data in a 3D terrain to portray an actual vision of the terrain. Mapinfo （a PC-based mapping software） provided attribute data，and coordinate transformation was achieved by linking surface points of the MapX two-dimensional map fused with the three dimensional terrain. The result was a forest resource database with village，town，and sub-compartment boundaries，that showed organic forest resource data in a 3D display. Integrated with GPS data，this forest fire prevention data realize fire prevention to detect combustible material buildups and fire controll.［Ch，7 fig. 11 ref.］
This research was designed to build a three dimensional（3D） background database for forest fire prevention. A new method using MapX （a coordinate transformation library） and OPEN Graphics Language （OpenGL） along with spatial information，data fusion，and 3D modeling technologies was developed to analyze features of a 3D background database. Digital Elevation Model（DEM） altitude data and OpenGL texture mapping were integrated with remote sensing data in a 3D terrain to portray an actual vision of the terrain. Mapinfo （a PC-based mapping software） provided attribute data，and coordinate transformation was achieved by linking surface points of the MapX two-dimensional map fused with the three dimensional terrain. The result was a forest resource database with village，town，and sub-compartment boundaries，that showed organic forest resource data in a 3D display. Integrated with GPS data，this forest fire prevention data realize fire prevention to detect combustible material buildups and fire controll.［Ch，7 fig. 11 ref.］
2008, 25(4): 411-416.
Abstract:
To cope with the system efficiency problems caused by mass-data and the centralized management in the forest resources database, the paper analyzed the spatial data management mechanism of ArcSDE spatial engine and worked out the optimization strategies for Oracle DBMS based spatial database system from four perspectives including database design, DBMS configuration, ArcSDE configuration and database maintenance. The provincial level forest resources spatial database of Fujian Province was taken as an example to validate the main optimization strategies. The results indicated that the rational adjustment of the parameters of DBMS and ArcSDE engine（Oracle SGA size, ArcSDE index size and MAXBUFSIZE）, optimization of the database design and adoption of the middle table technique could all improve the query efficiency significantly. For optimizing forest resources database, efficient logical database structure and distributed physical database structure should both be considered. ［Ch, 5 fig. 1 tab. 12 ref.］
To cope with the system efficiency problems caused by mass-data and the centralized management in the forest resources database, the paper analyzed the spatial data management mechanism of ArcSDE spatial engine and worked out the optimization strategies for Oracle DBMS based spatial database system from four perspectives including database design, DBMS configuration, ArcSDE configuration and database maintenance. The provincial level forest resources spatial database of Fujian Province was taken as an example to validate the main optimization strategies. The results indicated that the rational adjustment of the parameters of DBMS and ArcSDE engine（Oracle SGA size, ArcSDE index size and MAXBUFSIZE）, optimization of the database design and adoption of the middle table technique could all improve the query efficiency significantly. For optimizing forest resources database, efficient logical database structure and distributed physical database structure should both be considered. ［Ch, 5 fig. 1 tab. 12 ref.］
2008, 25(4): 417-421.
Abstract:
To estimate the carbon content of bamboo forest based on remote sensing，highly accurate data acquisition is necessary to reduce estimation errors. In this study，enhanced thematic mapper plus（ETM+） remote sensing data was used to extract bamboo forest data using a back propagation（BP） neural network. Matlab program language（Version 7.1） was used to compile the classification algorithm with algorithms of three training functions being compared；namely，Traingda-gradient descent backpropagation with adaptive learning rate backpropagation；Trainlm-levenberg-marquardt backpropagation；and Traingdm-gradient descent with momentum backpropagation. Results showed that for bamboo forest the BP neural network had a high classification accuracy with a producer accuracy of 84.0% and a user accuracy of 98.7%. Meanwhile，of the three different training functions Traingda had the highest classification accuracy，whereas Trainlm had the shortest training time. ［Ch，3 fig. 3 tab. 17 ref.］
To estimate the carbon content of bamboo forest based on remote sensing，highly accurate data acquisition is necessary to reduce estimation errors. In this study，enhanced thematic mapper plus（ETM+） remote sensing data was used to extract bamboo forest data using a back propagation（BP） neural network. Matlab program language（Version 7.1） was used to compile the classification algorithm with algorithms of three training functions being compared；namely，Traingda-gradient descent backpropagation with adaptive learning rate backpropagation；Trainlm-levenberg-marquardt backpropagation；and Traingdm-gradient descent with momentum backpropagation. Results showed that for bamboo forest the BP neural network had a high classification accuracy with a producer accuracy of 84.0% and a user accuracy of 98.7%. Meanwhile，of the three different training functions Traingda had the highest classification accuracy，whereas Trainlm had the shortest training time. ［Ch，3 fig. 3 tab. 17 ref.］
2008, 25(4): 422-426.
Abstract:
According to related regionalization principles，this research selected four indices including the area of forest land，shrubbery，non-stocked land and non-forestry land. Based on the principle of fuzzy cluster analysis，67 counties in Zhejiang Province were clustered into 5 groups. The results basically accorded with the actual condition. The results indicated that it was feasible to regionalize by fuzzy cluster. And other data were added to accomplish some more complicated regionalization. The regionalization results were meaningful for governments to make decision and manage the nature resource when it was partitioned by administrative unit. ［Ch，1 tab. 17 ref.］
According to related regionalization principles，this research selected four indices including the area of forest land，shrubbery，non-stocked land and non-forestry land. Based on the principle of fuzzy cluster analysis，67 counties in Zhejiang Province were clustered into 5 groups. The results basically accorded with the actual condition. The results indicated that it was feasible to regionalize by fuzzy cluster. And other data were added to accomplish some more complicated regionalization. The regionalization results were meaningful for governments to make decision and manage the nature resource when it was partitioned by administrative unit. ［Ch，1 tab. 17 ref.］
2008, 25(4): 427-430.
Abstract:
From Carya cathayensis，23 base pair （bp） primers designed according to a conserved sequence of the APETALA1 （AP1） gene，which has an important function in floral development，were used to amplify a 486 bp fragment by polymerase chain reaction（PCR）. The fragment was cloned into a pMD18-T vector and then sequenced. Next，the deduced amino acid sequence of the fragment was blasted with AP1 homologous genes of other 17 plants. Results of the 486 bp fragment cloned into a pMD18-T vector produced a fragment of the AP1 homologous gene：the CcAP1 gene. Also，the sequence analysis indicated two introns of 86 bp and 291 bp in the fragment with the exons encoding 36 amino acids. Afterward，when the CcAP1 gene was blasted with AP1 homologous genes，homology reached 69%－88%. This result suggested that the CcAP1 gene，registered in GenBank with the accession number EU155118，might have the same function of floral development as other AP1 homologous genes. ［Ch，3 fig. 1 tab. 11 ref.］
From Carya cathayensis，23 base pair （bp） primers designed according to a conserved sequence of the APETALA1 （AP1） gene，which has an important function in floral development，were used to amplify a 486 bp fragment by polymerase chain reaction（PCR）. The fragment was cloned into a pMD18-T vector and then sequenced. Next，the deduced amino acid sequence of the fragment was blasted with AP1 homologous genes of other 17 plants. Results of the 486 bp fragment cloned into a pMD18-T vector produced a fragment of the AP1 homologous gene：the CcAP1 gene. Also，the sequence analysis indicated two introns of 86 bp and 291 bp in the fragment with the exons encoding 36 amino acids. Afterward，when the CcAP1 gene was blasted with AP1 homologous genes，homology reached 69%－88%. This result suggested that the CcAP1 gene，registered in GenBank with the accession number EU155118，might have the same function of floral development as other AP1 homologous genes. ［Ch，3 fig. 1 tab. 11 ref.］
2008, 25(4): 431-436.
Abstract:
Using electronic microscopy，ultrastructural changes were observed during differentiation in a secondary xylem vessel element （VE） of Populus deltoides. Results showed that morphological development of VE differentiation was successively divided into three stages. First was prolongation of the primary cell wall （the initial stage），where the VE was highly vacuolated and the protoplasm was distributed along the cell wall. Second was establishment of the secondary cell wall （the pivotal stage） where substances accumulated before the tonoplast broke，and VE organelle structure was distinct. Golgi bodies and vesicles，which were associated closely with synthesis and transportation of secondary cell wall substances，were also abundant. After the tonoplast broke，these substances accumulated faster. Simultaneously，the protoplasm disaggregated，and the agglomerate chromatin was distributed over the margin of the nucleus showing typical characteristics of programmed cell death（PCD）. During secondary cell wall formation，no cell wall substances accumulated between terminal cell walls of neighboring VEs. In addition，terminal cell wall substances were disaggregated in the post secondary cell wall formation. Later，when the remnant terminal cell wall broke the third stage，perforation，occurred. Thus，for these successive stages of VE differentiation，the critical stage，when differentiation was not reversible，was at the start of secondary cell wall formation with succeeding VE differentiation similar to a typical PCD process. ［Ch，2 fig. 13 ref.］
Using electronic microscopy，ultrastructural changes were observed during differentiation in a secondary xylem vessel element （VE） of Populus deltoides. Results showed that morphological development of VE differentiation was successively divided into three stages. First was prolongation of the primary cell wall （the initial stage），where the VE was highly vacuolated and the protoplasm was distributed along the cell wall. Second was establishment of the secondary cell wall （the pivotal stage） where substances accumulated before the tonoplast broke，and VE organelle structure was distinct. Golgi bodies and vesicles，which were associated closely with synthesis and transportation of secondary cell wall substances，were also abundant. After the tonoplast broke，these substances accumulated faster. Simultaneously，the protoplasm disaggregated，and the agglomerate chromatin was distributed over the margin of the nucleus showing typical characteristics of programmed cell death（PCD）. During secondary cell wall formation，no cell wall substances accumulated between terminal cell walls of neighboring VEs. In addition，terminal cell wall substances were disaggregated in the post secondary cell wall formation. Later，when the remnant terminal cell wall broke the third stage，perforation，occurred. Thus，for these successive stages of VE differentiation，the critical stage，when differentiation was not reversible，was at the start of secondary cell wall formation with succeeding VE differentiation similar to a typical PCD process. ［Ch，2 fig. 13 ref.］
2008, 25(4): 437-441.
Abstract:
In order to breed drought-tolerant cultivars of pear，the effect of drought stress on membrane permeability and antioxidant enzyme systems the four one-year-old Pyrus（pear） species of（P. betulaefolia，P. pyrifolia，P. pashia，and P. pseudopashia） grown in pot，were studied in the Karst Fruit Tree Research Insititute of Guizhou University，from 2003 to 2005. Four treatments were set，including the control：the soil relative water content（SRWC） is（65.0 ± 5.0）%，light stress：the SRWC is（50.0 ± 5.0）%，moderate stress：the SRWC is（40.0 ± 5.0）%，severe stress：the SRWC is（32.5 ± 5.0）%，with three replication. Results showed that malondialdehyde（MDA） content significantly decreased（P＜0.01） with light stress for P. pyrifolia，but significantly increased（P＜0.01） with moderate and severe stress for all species. With severe drought stress，damage to the membrane structure of P. pyrifolia was greater than the other three species. Damage for P. pyrifolia was 35.91%，while P. pseudopashia was 10.72%，P. pashia was 10.34% and P. betulaefolia was 8.00%. Superoxide dismutase（SOD） activities of P. pyrifolia decreased，while the other three species first increased with light stress and then decreased with moderate and severe stress. Peroxidase（POD） and catalase（CAT） activities decreased for the four species. With drought stress and elimination of oxygen free radicals，the four Pyrus species avoided injury in the following order：P. pyrifolia ＞ P. pseudopashia ＞ P. pashia ＞ P. betulaefolia. ［Ch，3 fig. 1 tab. 19 ref.］
In order to breed drought-tolerant cultivars of pear，the effect of drought stress on membrane permeability and antioxidant enzyme systems the four one-year-old Pyrus（pear） species of（P. betulaefolia，P. pyrifolia，P. pashia，and P. pseudopashia） grown in pot，were studied in the Karst Fruit Tree Research Insititute of Guizhou University，from 2003 to 2005. Four treatments were set，including the control：the soil relative water content（SRWC） is（65.0 ± 5.0）%，light stress：the SRWC is（50.0 ± 5.0）%，moderate stress：the SRWC is（40.0 ± 5.0）%，severe stress：the SRWC is（32.5 ± 5.0）%，with three replication. Results showed that malondialdehyde（MDA） content significantly decreased（P＜0.01） with light stress for P. pyrifolia，but significantly increased（P＜0.01） with moderate and severe stress for all species. With severe drought stress，damage to the membrane structure of P. pyrifolia was greater than the other three species. Damage for P. pyrifolia was 35.91%，while P. pseudopashia was 10.72%，P. pashia was 10.34% and P. betulaefolia was 8.00%. Superoxide dismutase（SOD） activities of P. pyrifolia decreased，while the other three species first increased with light stress and then decreased with moderate and severe stress. Peroxidase（POD） and catalase（CAT） activities decreased for the four species. With drought stress and elimination of oxygen free radicals，the four Pyrus species avoided injury in the following order：P. pyrifolia ＞ P. pseudopashia ＞ P. pashia ＞ P. betulaefolia. ［Ch，3 fig. 1 tab. 19 ref.］
2008, 25(4): 442-443.
Abstract:
Meliosma flexuosa var. pubicarpa，a new variety of Sabiaceae from Zhejiang of China，is described and illustrated. This new variety differs from var. flexuosa in its brown pubescent drupes. A key to this variety and its similar taxa is proposed as well.［Ch，1 fig. 11 ref.］
Meliosma flexuosa var. pubicarpa，a new variety of Sabiaceae from Zhejiang of China，is described and illustrated. This new variety differs from var. flexuosa in its brown pubescent drupes. A key to this variety and its similar taxa is proposed as well.［Ch，1 fig. 11 ref.］
2008, 25(4): 444-450.
Abstract:
Adjacent grid points were used to obtain data for an analysis of dominant degree. Then，with a plot size of 100 m×100 m，Hegyi’s competition index model for individual trees was used to determine competition within dominant tree populations in an evergreen broad-leaved forest of National Nature Reserve of Mount Tianmu. We investigate trees greater than 5 cm diameter at breast-height（DBH），and determine the species and individual number. Results showed that there were 1 794 trees greater than 5 cm DBH，82 species. From the analysis of dominant degrees showed it contained 8 dominant tree species which were 1 074 individuals in all，Cyclobalanopsis myrsinaefolia，Cyclobalanopsis glauca，and Liquidambar formosana of evergreen broad-leaved trees，and Liquidambar formosana，Cunninghamia lanceolata，Quercus fabri，Torreya grandis，and Pistacia chinensis of non-evergreen broad-leaved trees. The three evergreen broad-leaved dominant populations，had a total plant number of about 71.6% and a total basal area at breast-height of about 44.6%. In the plot，for trees greater than 5 cm DBH，competition among the 8 dominant populations revealed great competition，and an evergreen broad-leaved populations exhibited greater competition than non-broad-leaved populations. Competition in evergreen broad-leaved dominant opulations for intraspecies and interspecies had an intensity order of C. myrsinaefolia ＞ C. glauca ＞ L. formosana with the interspecies competition greater than intraspecies. Competition intensity and DBH of a tree had an exponential relationship （P＜0.01） by regression analysis. Competition intensity of a dominant tree population decreased when tree DBH increased. When tree DBH reached 20 cm，the change range of competition intensity was narrow. Therefore，we can adjust the community structure and succession courses for evergreen broad-leaved forest according to this characteristic for effective protection and sustainable management. ［Ch，1 fig. 3 tab. 15 ref.］
Adjacent grid points were used to obtain data for an analysis of dominant degree. Then，with a plot size of 100 m×100 m，Hegyi’s competition index model for individual trees was used to determine competition within dominant tree populations in an evergreen broad-leaved forest of National Nature Reserve of Mount Tianmu. We investigate trees greater than 5 cm diameter at breast-height（DBH），and determine the species and individual number. Results showed that there were 1 794 trees greater than 5 cm DBH，82 species. From the analysis of dominant degrees showed it contained 8 dominant tree species which were 1 074 individuals in all，Cyclobalanopsis myrsinaefolia，Cyclobalanopsis glauca，and Liquidambar formosana of evergreen broad-leaved trees，and Liquidambar formosana，Cunninghamia lanceolata，Quercus fabri，Torreya grandis，and Pistacia chinensis of non-evergreen broad-leaved trees. The three evergreen broad-leaved dominant populations，had a total plant number of about 71.6% and a total basal area at breast-height of about 44.6%. In the plot，for trees greater than 5 cm DBH，competition among the 8 dominant populations revealed great competition，and an evergreen broad-leaved populations exhibited greater competition than non-broad-leaved populations. Competition in evergreen broad-leaved dominant opulations for intraspecies and interspecies had an intensity order of C. myrsinaefolia ＞ C. glauca ＞ L. formosana with the interspecies competition greater than intraspecies. Competition intensity and DBH of a tree had an exponential relationship （P＜0.01） by regression analysis. Competition intensity of a dominant tree population decreased when tree DBH increased. When tree DBH reached 20 cm，the change range of competition intensity was narrow. Therefore，we can adjust the community structure and succession courses for evergreen broad-leaved forest according to this characteristic for effective protection and sustainable management. ［Ch，1 fig. 3 tab. 15 ref.］
2008, 25(4): 451-457.
Abstract:
Davidia involucrata is a relic species of paleotropical kingdom in Tertiary period，belonging to Davidiaceae with a single genus. In recent years，the increase of regional developing projects has led to a sharp decrease of this species in natural population. The population characteristics of D. involucrata were discussed here，and the dynamic changes of its population were analyzed systematically，in order to provide basic data for further study，and to probe into conservation policy on this species. Quadrates with a contiguous grid were used to collect field data of D. involucrata at Labahe Nature Reserve of Sichuan Province. Size and height class structures were established；a time-specific life table was produced；and survivorship curves were drawn. A t-test of the variance/mean （v/m） ratio，the negative binomial parameter，the mean crowding index，and the patchiness index were used to analyze the distribution pattern and dynamics. The results showed：（1） the population structure of the D. involucrata population was a inverse-pyramid type. （2）The structure of D. involucrata population was declining due to a lack of seedlings. （3） Also，the main regeneration mode of D. involucrata was asexual reproduction. （4）From early age to old age，the population was first characterized as unstable，then stable，and finally degraded with a type Ⅲ Deevey Curve describing survival. （5）Generally，the D. involucrata population was clumpy，and the aggregation intensity tended to decrease from the sapling to the mature tree stage，the aggregation intensity also changed with block sizes. The results above indicated that the interaction between biological and ecological properties mainly decided the spatial population structure and distribution pattern. ［Ch，3 fig. 5 tab. 22 ref.］
Davidia involucrata is a relic species of paleotropical kingdom in Tertiary period，belonging to Davidiaceae with a single genus. In recent years，the increase of regional developing projects has led to a sharp decrease of this species in natural population. The population characteristics of D. involucrata were discussed here，and the dynamic changes of its population were analyzed systematically，in order to provide basic data for further study，and to probe into conservation policy on this species. Quadrates with a contiguous grid were used to collect field data of D. involucrata at Labahe Nature Reserve of Sichuan Province. Size and height class structures were established；a time-specific life table was produced；and survivorship curves were drawn. A t-test of the variance/mean （v/m） ratio，the negative binomial parameter，the mean crowding index，and the patchiness index were used to analyze the distribution pattern and dynamics. The results showed：（1） the population structure of the D. involucrata population was a inverse-pyramid type. （2）The structure of D. involucrata population was declining due to a lack of seedlings. （3） Also，the main regeneration mode of D. involucrata was asexual reproduction. （4）From early age to old age，the population was first characterized as unstable，then stable，and finally degraded with a type Ⅲ Deevey Curve describing survival. （5）Generally，the D. involucrata population was clumpy，and the aggregation intensity tended to decrease from the sapling to the mature tree stage，the aggregation intensity also changed with block sizes. The results above indicated that the interaction between biological and ecological properties mainly decided the spatial population structure and distribution pattern. ［Ch，3 fig. 5 tab. 22 ref.］
2008, 25(4): 458-463.
Abstract:
For the evergreen broad?鄄leaved forest in National Nature Reserve of Mount Jiulianshan，Jiangxi Province，plot sampling（75 plots of 10 m × 10 m） and importance value were used to quantify species and describe their structural characteristics. Results of sampling showed that the typical evergreen broad-leaved forest of Mt. Jiulianshan consisted mainly of subtropical families and genera with dominant families including Fagaceae，Lauraceae，Camelliaceae，Styracaceae，Ericaceae，and Magnoliaceae. Tree density for diameter at breast height （DBH）≥3 cm was 1 808 individuals per hectare with an average height of 11.5 m. Vertical tree stratification was apparent，and horizontal distribution was uneven with an average DBH of 14.2 cm. Vegetation on Mt. Jiulianshan consisted of a combination of natural forest，secondary natural forest，and silvicultural regeneration. Some evergreen broad-leaved communities were over-mature or being regenerated. In addition，various hardwood trees were found，such as Liquidambar formosana，Alniphyllum fortunei，and Betula luminifera，which invaded canopy gaps forming mixed evergreen and hardwood broad-leaved forests.［Ch，1 fig. 3 tab. 21 ref.］
For the evergreen broad?鄄leaved forest in National Nature Reserve of Mount Jiulianshan，Jiangxi Province，plot sampling（75 plots of 10 m × 10 m） and importance value were used to quantify species and describe their structural characteristics. Results of sampling showed that the typical evergreen broad-leaved forest of Mt. Jiulianshan consisted mainly of subtropical families and genera with dominant families including Fagaceae，Lauraceae，Camelliaceae，Styracaceae，Ericaceae，and Magnoliaceae. Tree density for diameter at breast height （DBH）≥3 cm was 1 808 individuals per hectare with an average height of 11.5 m. Vertical tree stratification was apparent，and horizontal distribution was uneven with an average DBH of 14.2 cm. Vegetation on Mt. Jiulianshan consisted of a combination of natural forest，secondary natural forest，and silvicultural regeneration. Some evergreen broad-leaved communities were over-mature or being regenerated. In addition，various hardwood trees were found，such as Liquidambar formosana，Alniphyllum fortunei，and Betula luminifera，which invaded canopy gaps forming mixed evergreen and hardwood broad-leaved forests.［Ch，1 fig. 3 tab. 21 ref.］
2008, 25(4): 464-468.
Abstract:
Soil seed bank in Cryptomeria fortunei stand had never been studied before，but the status of the forest’s soil seed bank has important influence on the forest’s development. The soil seed bank and regeneration of the old-growth Cryptomeria fortunei on Mount Tianmu were determined using sample line approach. Results showed that the soil seed bank was short-term persistent as there were no vital seeds in the seed bank after the spring germination period with seeds being 60%－70% immature and the rest rotten. Thus，one reason for the failure of natural regeneration of old-growth C. fortunei is low vitality，a heavy litter layer，lack of sunshine，and allelopathy；therefore artificial reforestation should be considered. ［Ch，4 tab. 21 ref.］
Soil seed bank in Cryptomeria fortunei stand had never been studied before，but the status of the forest’s soil seed bank has important influence on the forest’s development. The soil seed bank and regeneration of the old-growth Cryptomeria fortunei on Mount Tianmu were determined using sample line approach. Results showed that the soil seed bank was short-term persistent as there were no vital seeds in the seed bank after the spring germination period with seeds being 60%－70% immature and the rest rotten. Thus，one reason for the failure of natural regeneration of old-growth C. fortunei is low vitality，a heavy litter layer，lack of sunshine，and allelopathy；therefore artificial reforestation should be considered. ［Ch，4 tab. 21 ref.］
2008, 25(4): 469-474.
Abstract:
An experiment was conducted in the evergreen broad-leaved forest （the primitive tree species were Castanopsis wattii and Lithocarpus xylocarpus） of Ailaoshan，Yunnan Province to evaluate its water interception capability and accumulate basic data for forest hydrology. A total of 144 precipitation events from May 2005 to May 2006 were monitored，and a correlation analysis was used to determine the redistribution and interception effects of the tree canopy on precipitation. The total of 1 707.8 mm of precipitation，consisted of throughfall，1 421.8 mm （83.3%）；stemflow，15.4 mm （0.9%）；and canopy interception，270.6 mm （15.8%）. However，throughfall and stemflow could only be recorded when precipitation was over 3.7 mm. A “funnel” shaped canopy structure and duration of rainfall sometimes caused recorded rainfall to be greater than real precipitation；meanwhile a low stemflow of tree with greater diameter at breast height and crowns sometimes resulted from large branch angles and lots of epigrowth. Total throughfall，stemflow，and canopy interception were positively correlated（P＜0.01） with precipitation，whereas the canopy interception rate was negatively correlated（P＜0.01） with precipitation. Thus，precipitation and forest structure mainly determined interception capability. ［Ch，3 fig. 3 tab. 20 ref.］
An experiment was conducted in the evergreen broad-leaved forest （the primitive tree species were Castanopsis wattii and Lithocarpus xylocarpus） of Ailaoshan，Yunnan Province to evaluate its water interception capability and accumulate basic data for forest hydrology. A total of 144 precipitation events from May 2005 to May 2006 were monitored，and a correlation analysis was used to determine the redistribution and interception effects of the tree canopy on precipitation. The total of 1 707.8 mm of precipitation，consisted of throughfall，1 421.8 mm （83.3%）；stemflow，15.4 mm （0.9%）；and canopy interception，270.6 mm （15.8%）. However，throughfall and stemflow could only be recorded when precipitation was over 3.7 mm. A “funnel” shaped canopy structure and duration of rainfall sometimes caused recorded rainfall to be greater than real precipitation；meanwhile a low stemflow of tree with greater diameter at breast height and crowns sometimes resulted from large branch angles and lots of epigrowth. Total throughfall，stemflow，and canopy interception were positively correlated（P＜0.01） with precipitation，whereas the canopy interception rate was negatively correlated（P＜0.01） with precipitation. Thus，precipitation and forest structure mainly determined interception capability. ［Ch，3 fig. 3 tab. 20 ref.］
2008, 25(4): 475-480.
Abstract:
To enhance absorption of air pollution within city landscapes，resistance and absorption of 38 important landscaping plant species in Zhejiang Province were measured after subjection to gaseous hydrogen fluoride（HF） fumigation. A linear correlation analysis was conducted between resistance and absorption，and then these parameters were divided into 5 levels from strong （5） to weak （1） for a cluster analysis. Results showed plants with a range of resistances to F from the strongest with Ophiopogon japonicus，which resisted 9 h of fumigation to the weakest with Liquidambar formosana，which resisted only 2 h. For deciduous plants the weakest resistance levels （1 and 2） were found in 87.50% of the specimens，whereas evergreen plants were spread fairly evenly in levels 1 to 4. Absorption of plants ranged widely with the greatest in Zelkova serrata having 13.66 g·kg－1 HF；this was 116.65 times more than Pinus elliottii，which had the least absorption with 117.06 mg·kg－1 HF. For deciduous plants，37.5% of the specimens were found in absorption level 3 with decreasing amounts in the stronger and weaker levels；whereas with evergreen plants，the percentage of specimens continually decreased from the weakest to the strongest levels. Also，there was no significant linear correlation between resistance and absorption of plants.［Ch，2 fig. 5 tab. 13 ref.］
To enhance absorption of air pollution within city landscapes，resistance and absorption of 38 important landscaping plant species in Zhejiang Province were measured after subjection to gaseous hydrogen fluoride（HF） fumigation. A linear correlation analysis was conducted between resistance and absorption，and then these parameters were divided into 5 levels from strong （5） to weak （1） for a cluster analysis. Results showed plants with a range of resistances to F from the strongest with Ophiopogon japonicus，which resisted 9 h of fumigation to the weakest with Liquidambar formosana，which resisted only 2 h. For deciduous plants the weakest resistance levels （1 and 2） were found in 87.50% of the specimens，whereas evergreen plants were spread fairly evenly in levels 1 to 4. Absorption of plants ranged widely with the greatest in Zelkova serrata having 13.66 g·kg－1 HF；this was 116.65 times more than Pinus elliottii，which had the least absorption with 117.06 mg·kg－1 HF. For deciduous plants，37.5% of the specimens were found in absorption level 3 with decreasing amounts in the stronger and weaker levels；whereas with evergreen plants，the percentage of specimens continually decreased from the weakest to the strongest levels. Also，there was no significant linear correlation between resistance and absorption of plants.［Ch，2 fig. 5 tab. 13 ref.］
2008, 25(4): 481-485.
Abstract:
To research characteristics of changes in negative air ion concentration and their relationships with environmental factors in the Mount Tianmu Nature Reserve，measurements were made with an air ion measuring instrument，a microcomputer laser dust collecting instrument，and a temperature-humidity recorder. Then，diurnal variations （08：00－17：00） and annual variations were tested with a correlation analysis between negative air ions and 1） particle matter with aerodynamic diameter ＜10 μm，2） relative humidity，and 3） air temperature. Results showed that negative air ion concentration for selected plant communities was in the following order：Cryptomeria fortunei （1 331 particle·cm-3） ＞ Phoebe sheareri （1 223 particle·cm-3）＞ Ginkgo biloba （960 particle·cm-3）＞ Phyllostachys pubescens （701 particle·cm-3）. Diurnal variations of negative air ion concentration was significantly and negatively correlated with PM10（r= －0.812，P＜0.01），significantly and positively correlated with relative humidity （r=0.820，P＜0.01），and significantly and negatively correlated with air temperature （r= －0.676，P＜0.05）. Therefore，dynamic water movement，such as from waterfalls and streams，could increase the negative air ion concentration. ［Ch，4 fig. 2 tab. 23 ref.］
To research characteristics of changes in negative air ion concentration and their relationships with environmental factors in the Mount Tianmu Nature Reserve，measurements were made with an air ion measuring instrument，a microcomputer laser dust collecting instrument，and a temperature-humidity recorder. Then，diurnal variations （08：00－17：00） and annual variations were tested with a correlation analysis between negative air ions and 1） particle matter with aerodynamic diameter ＜10 μm，2） relative humidity，and 3） air temperature. Results showed that negative air ion concentration for selected plant communities was in the following order：Cryptomeria fortunei （1 331 particle·cm-3） ＞ Phoebe sheareri （1 223 particle·cm-3）＞ Ginkgo biloba （960 particle·cm-3）＞ Phyllostachys pubescens （701 particle·cm-3）. Diurnal variations of negative air ion concentration was significantly and negatively correlated with PM10（r= －0.812，P＜0.01），significantly and positively correlated with relative humidity （r=0.820，P＜0.01），and significantly and negatively correlated with air temperature （r= －0.676，P＜0.05）. Therefore，dynamic water movement，such as from waterfalls and streams，could increase the negative air ion concentration. ［Ch，4 fig. 2 tab. 23 ref.］
2008, 25(4): 486-490.
Abstract:
Growing altitude and bamboo growth history were used to analyze the status and the evolution of soil fertility according to four aspects，namely 1） water-holding capacity，2） soil acidification in four Phyllostachys pubescens bamboo stands （on a valley bottom，middle slope，upside slope and a valley top） of southern Sichuan，and nutrient status，and profile characteristics of soil. Results showed that 1） soil structure in the rhizosphere was very high；water-holding capacity and organism count in the soil increased with altitude and duration of bamboo growth. However，soil etiolation and soil acidification was obvious. 2） Soil acidity was adjusted with lime；best applications were 10.625 t·hm－2 on the valley bottom，14.811 t·hm－2 for the middle slope，and 12.558 t·hm－2 on the valley top. 3） In all the soils，N for attaining high yield was insufficient；K was insufficient or very insufficient；and P was extremely insufficient. Therefore，at present，N and P fertilization is the best way to increase yield of Phyllostachys pubescens bamboo stands in southern Sichuan.［Ch，3 tab. 22 ref.］
Growing altitude and bamboo growth history were used to analyze the status and the evolution of soil fertility according to four aspects，namely 1） water-holding capacity，2） soil acidification in four Phyllostachys pubescens bamboo stands （on a valley bottom，middle slope，upside slope and a valley top） of southern Sichuan，and nutrient status，and profile characteristics of soil. Results showed that 1） soil structure in the rhizosphere was very high；water-holding capacity and organism count in the soil increased with altitude and duration of bamboo growth. However，soil etiolation and soil acidification was obvious. 2） Soil acidity was adjusted with lime；best applications were 10.625 t·hm－2 on the valley bottom，14.811 t·hm－2 for the middle slope，and 12.558 t·hm－2 on the valley top. 3） In all the soils，N for attaining high yield was insufficient；K was insufficient or very insufficient；and P was extremely insufficient. Therefore，at present，N and P fertilization is the best way to increase yield of Phyllostachys pubescens bamboo stands in southern Sichuan.［Ch，3 tab. 22 ref.］
2008, 25(4): 491-496.
Abstract:
Research on the spatio?鄄temporal variation law of soil water content in a subsidence area，especially in a semi?鄄arid mining area，was conducted to help reestablish a sound ecological system. In this study，water loss in sandy soils of the Bulanta coal mining area in the southeast part of the Mu Us Desert was analyzed and discussed using a spatial contrast method and correlation analysis in 2005 and 2006. One sand dune without mining was the control，and the others subsided respectively in March of 2005 and July of 2004. Results showed that the degree of soil collapse was significantly and negatively correlated （r=－0.73，P＜0.05） to the water content of sand dunes. For 0 - 100 cm depths，during both the rainy and drought seasons，1） water content of non-collapsed dunes was significantly greater （P＜0.01） than collapsed dunes；2） at different depths，water content in non-collapsed dunes was significantly greater （P＜0.01） than corresponding depths in collapsed dunes，except of 60 - 100 cm depths；and 3） except for the top of 2004 year collapsing dune，for different locations，water content of non-collapsed dunes was significantly greater （P＜0.05） than corresponding locations of collapsed dunes. ［Ch，3 fig. 2 tab. 13 ref.］
Research on the spatio?鄄temporal variation law of soil water content in a subsidence area，especially in a semi?鄄arid mining area，was conducted to help reestablish a sound ecological system. In this study，water loss in sandy soils of the Bulanta coal mining area in the southeast part of the Mu Us Desert was analyzed and discussed using a spatial contrast method and correlation analysis in 2005 and 2006. One sand dune without mining was the control，and the others subsided respectively in March of 2005 and July of 2004. Results showed that the degree of soil collapse was significantly and negatively correlated （r=－0.73，P＜0.05） to the water content of sand dunes. For 0 - 100 cm depths，during both the rainy and drought seasons，1） water content of non-collapsed dunes was significantly greater （P＜0.01） than collapsed dunes；2） at different depths，water content in non-collapsed dunes was significantly greater （P＜0.01） than corresponding depths in collapsed dunes，except of 60 - 100 cm depths；and 3） except for the top of 2004 year collapsing dune，for different locations，water content of non-collapsed dunes was significantly greater （P＜0.05） than corresponding locations of collapsed dunes. ［Ch，3 fig. 2 tab. 13 ref.］
2008, 25(4): 502-506.
Abstract:
Insect communities in four Eucalyptus plantations （Ⅰ-Eucalyptus in Xiaozhong Village of Julin Township，Ⅱ-Eucalyptus in Anding Village of Huangguayuan Township，Ⅲ-Eucalyptus-Azadirachta indica in Maoyi Village of Laocheng Township，and Ⅳ-Eucalyptus-Leucaena leucocephala in Xialeiwo Village of Nengyu Township） （with one plot with 1 hm2 in each） in the Yuanmou Arid-hot Valley of Yunnan Province were surveyed during 2005 using sweep netting in the tree-shrub-grass layer and pitfall trapping in the litter layer. Totals of all plots showed that sweep netting captured 2 541 insects belonging to 218 species，84 families，and 11 orders with the order Hemiptera having the most species and individuals；whereas pitfall trapping caught 6 602 insects belonging to 121 species，49 families，and 12 orders with Hymenoptera having the most species and individuals. In the tree-shrub-grass layer，species diversity（number of species S，Shannon-Wiener diversity index H’，and Pielou evenness index E） of the insect communities was in the order：Ⅰ＞Ⅱ＞Ⅲ＞Ⅳ，whereas in the litter layer it was： Ⅲ＞Ⅳ＞Ⅰ＞Ⅱ. Thus，among these four plantations，for the tree-shrub-grass layer，vegetation had a stronger effect on insect community diversity，while in the litter layer，herbaceous cover had more influence. ［Ch，4 tab. 15 ref.］
Insect communities in four Eucalyptus plantations （Ⅰ-Eucalyptus in Xiaozhong Village of Julin Township，Ⅱ-Eucalyptus in Anding Village of Huangguayuan Township，Ⅲ-Eucalyptus-Azadirachta indica in Maoyi Village of Laocheng Township，and Ⅳ-Eucalyptus-Leucaena leucocephala in Xialeiwo Village of Nengyu Township） （with one plot with 1 hm2 in each） in the Yuanmou Arid-hot Valley of Yunnan Province were surveyed during 2005 using sweep netting in the tree-shrub-grass layer and pitfall trapping in the litter layer. Totals of all plots showed that sweep netting captured 2 541 insects belonging to 218 species，84 families，and 11 orders with the order Hemiptera having the most species and individuals；whereas pitfall trapping caught 6 602 insects belonging to 121 species，49 families，and 12 orders with Hymenoptera having the most species and individuals. In the tree-shrub-grass layer，species diversity（number of species S，Shannon-Wiener diversity index H’，and Pielou evenness index E） of the insect communities was in the order：Ⅰ＞Ⅱ＞Ⅲ＞Ⅳ，whereas in the litter layer it was： Ⅲ＞Ⅳ＞Ⅰ＞Ⅱ. Thus，among these four plantations，for the tree-shrub-grass layer，vegetation had a stronger effect on insect community diversity，while in the litter layer，herbaceous cover had more influence. ［Ch，4 tab. 15 ref.］
2008, 25(4): 507-512.
Abstract:
From 18 January to 21 February 2007，the feeding site selection of ring-necked pheasants （Phasianus colchicus） was surveyed in the National Nature Reserve of Mount Qingliangfeng in Zhejiang Province. Representative sampling method was used to find their feeding sites，and the variables affecting their feeding site selection were determined according to the condition of observed area. The principal component analysis was used to define the variables which were important for their feeding site selection，and then the independent-samples t and Mann-Whitney U were used to analyze the selectivity. A total of 14 feeding sites were found. The ring-necked pheasants prefer the under slope position as their feeding site （for 64.29% of all feeding sites）. Owing to the common effects of the food richness and concealment condition，the species select feeding sites with the higher richness of shrub and grass，the lower grass density and cover，and especially prefer the close shrub and sparse grass （50.00%）. ［Ch，2 fig. 3 tab. 35 ref.］
From 18 January to 21 February 2007，the feeding site selection of ring-necked pheasants （Phasianus colchicus） was surveyed in the National Nature Reserve of Mount Qingliangfeng in Zhejiang Province. Representative sampling method was used to find their feeding sites，and the variables affecting their feeding site selection were determined according to the condition of observed area. The principal component analysis was used to define the variables which were important for their feeding site selection，and then the independent-samples t and Mann-Whitney U were used to analyze the selectivity. A total of 14 feeding sites were found. The ring-necked pheasants prefer the under slope position as their feeding site （for 64.29% of all feeding sites）. Owing to the common effects of the food richness and concealment condition，the species select feeding sites with the higher richness of shrub and grass，the lower grass density and cover，and especially prefer the close shrub and sparse grass （50.00%）. ［Ch，2 fig. 3 tab. 35 ref.］
2008, 25(4): 513-516.
Abstract:
Hiking arises from people longing for return to nature and tradition. At present，hiking is a spontaneous activity with little theoretical research. Based on the very few existing research in China，the paper classified the hiking routes and proposed four principles for the selection of hiking routes，namely，remote，primitive，challenging and thematic. The key points for the development of hiking routes were as follows：theme，scale and challenge should be highlighted；the protection of the ecological environment should be attached great importance to；a set of effective safety guarantee system should be built；cross-regional cooperation and socialized security and management should be conducted. Especially，hiking is not only a tourist activity but also a new tourism development mode. ［Ch，1 tab. 11 ref.］
Hiking arises from people longing for return to nature and tradition. At present，hiking is a spontaneous activity with little theoretical research. Based on the very few existing research in China，the paper classified the hiking routes and proposed four principles for the selection of hiking routes，namely，remote，primitive，challenging and thematic. The key points for the development of hiking routes were as follows：theme，scale and challenge should be highlighted；the protection of the ecological environment should be attached great importance to；a set of effective safety guarantee system should be built；cross-regional cooperation and socialized security and management should be conducted. Especially，hiking is not only a tourist activity but also a new tourism development mode. ［Ch，1 tab. 11 ref.］
2008, 25(4): 517-521.
Abstract:
Trophic levels of Honghu Lake in Hubei Province were determined for more effective referencing and decision-making with lake management. Total phosphorus（TP），total nitrogen（TN），chemical oxygen demand for manganese，secchi disk depth（SD），and chlorophll-a（chl-a） for the inlet，breeding，open water，and wetland protection regions as well as the whole of Honghu Lake were measured. Then results of the fuzzy mathematics method were compared to the comprehensive trophic level index method，and these were evaluated against the data. Results of the fuzzy mathematics method showed that the inlet and breeding regions were slightly eutrophic，whereas the other three locations were mesotrophic. However，the comprehensive trophic level index method revealed that the inlet region was slightly eutorphic，while the other four locations were mesotrophic. Data collected showed that the fuzzy mathematics method was closer to the actual levels than the comprehensive trophic level index method，and that the entire lake was becoming eutrophic. ［Ch，1 fig. 3 tab. 19 ref.］
Trophic levels of Honghu Lake in Hubei Province were determined for more effective referencing and decision-making with lake management. Total phosphorus（TP），total nitrogen（TN），chemical oxygen demand for manganese，secchi disk depth（SD），and chlorophll-a（chl-a） for the inlet，breeding，open water，and wetland protection regions as well as the whole of Honghu Lake were measured. Then results of the fuzzy mathematics method were compared to the comprehensive trophic level index method，and these were evaluated against the data. Results of the fuzzy mathematics method showed that the inlet and breeding regions were slightly eutrophic，whereas the other three locations were mesotrophic. However，the comprehensive trophic level index method revealed that the inlet region was slightly eutorphic，while the other four locations were mesotrophic. Data collected showed that the fuzzy mathematics method was closer to the actual levels than the comprehensive trophic level index method，and that the entire lake was becoming eutrophic. ［Ch，1 fig. 3 tab. 19 ref.］
2008, 25(4): 497-501.
Abstract:
This objective was to provide basis for the biological extracting of the spinning bamboo fiber. The strain ZNLD-18，separated from decaying bamboo，which was able to decompose selectively the bamboo lignin，was identified by polymerase chain reaction （PCR）. The rDNA ITS sequences of the strain were amplified and tested by the fungi universal primers ITS1 and ITS4. The sequence length was 541 base pair（bp）. The sequences were Blast searched within the GenBank to obtain the different strains’ sequences with the similar homology. The comparison of the genetic distances of these sequences showed that the ITS sequences of ZNLD-18 and Trametes versicolor were with over 99% homology. A molecular phylogenetic tree was built with Phylogenetic Analysis Using Parsimony （PAUP） software. Given the analysis results of the tree and the morphological characteristics of the strain，ZNLD-18 was Trametes versicolor. ［Ch，2 fig. 2 tab. 14 ref.］
This objective was to provide basis for the biological extracting of the spinning bamboo fiber. The strain ZNLD-18，separated from decaying bamboo，which was able to decompose selectively the bamboo lignin，was identified by polymerase chain reaction （PCR）. The rDNA ITS sequences of the strain were amplified and tested by the fungi universal primers ITS1 and ITS4. The sequence length was 541 base pair（bp）. The sequences were Blast searched within the GenBank to obtain the different strains’ sequences with the similar homology. The comparison of the genetic distances of these sequences showed that the ITS sequences of ZNLD-18 and Trametes versicolor were with over 99% homology. A molecular phylogenetic tree was built with Phylogenetic Analysis Using Parsimony （PAUP） software. Given the analysis results of the tree and the morphological characteristics of the strain，ZNLD-18 was Trametes versicolor. ［Ch，2 fig. 2 tab. 14 ref.］
2008, 25(4): 522-526.
Abstract:
Moso bamboo（Phyllostachys pubescens） is a fast growing bamboo species with important economic and ecological value. The objective is to grasp of the spatio-temporal dynamics of photosynthesis in moso bamboo leaf. In autumn 2006，a Li-6400 portable photosynthesis system was set up in natural field conditions to determine diurnal variation of gas exchange and response of photosynthesis to light intensities in different layers of the bamboo canopy （1st－7th branches from low to up was upper layer，8th - 14th was middle layer，and≥15th was upper layer）. Results showed that for diurnal changes in autumn，the net photosynthetic rate（Pn） had a double-peaked curve with peaks at about 09:00（am） and about 15:00 （pm） and a “midday depression” from 11:00 －14:00，which was due to the absence of irradiance and closure of some stomata. Also，the diurnal transpiration rate was a single-peaked curve，while the diurnal water use efficiency（WUE） was a double-peaked curve. Additionally，light response in the upper and lower layers of the bamboo stand showed that with the same photosynthetic photon flux density，Pn was greater in the upper layer. Adaptations of leaves in the two layers may have caused the difference light intensities with leaves in the upper layer better adapted to the stronger light. ［Ch，6 fig. 22 ref.］
Moso bamboo（Phyllostachys pubescens） is a fast growing bamboo species with important economic and ecological value. The objective is to grasp of the spatio-temporal dynamics of photosynthesis in moso bamboo leaf. In autumn 2006，a Li-6400 portable photosynthesis system was set up in natural field conditions to determine diurnal variation of gas exchange and response of photosynthesis to light intensities in different layers of the bamboo canopy （1st－7th branches from low to up was upper layer，8th - 14th was middle layer，and≥15th was upper layer）. Results showed that for diurnal changes in autumn，the net photosynthetic rate（Pn） had a double-peaked curve with peaks at about 09:00（am） and about 15:00 （pm） and a “midday depression” from 11:00 －14:00，which was due to the absence of irradiance and closure of some stomata. Also，the diurnal transpiration rate was a single-peaked curve，while the diurnal water use efficiency（WUE） was a double-peaked curve. Additionally，light response in the upper and lower layers of the bamboo stand showed that with the same photosynthetic photon flux density，Pn was greater in the upper layer. Adaptations of leaves in the two layers may have caused the difference light intensities with leaves in the upper layer better adapted to the stronger light. ［Ch，6 fig. 22 ref.］
2008, 25(4): 527-531.
Abstract:
Carya cathayensis is famous because its nut has rich nutrition，especially in oil and protein. We explore the nut’s growth process in order to obtain the law of oil accumulation. From May to September in 2006，we picked 150－300 nuts from 6 sample trees each 7－10 days. Then，we determine its diameter，fresh and dry weight，the weight rate of kernel to shell，crude protein，soluble sugar，and crude fat. Results showed that development of the Carya cathayensis nut throughout its growing season is divided into two distinct phases. Phase Ⅰ occurred from early May to early August. During this phase the C. cathayensis nut enlarged with the fastest growth in June and July and came to full size. Phase Ⅱ occurred from early August until harvest in early September，wherein the kernel developed and filled out with nutrients accumulating and transforming. In this phase，significant negative correlations were found between crude protein and crude fat （r =－0.991 3，P＜0.01） and between soluble sugar and crude fat （r = －0.956 5，P＜0.01）with protein content decreasing from 117.4 to 93.6 mg·g－1，soluble sugar decreasing from 56.1 to 19.67 mg·g－1，and crude fat continuously increasing from 33.9% to 69.0%. So we should provide adequate nutrition to maintain the vitality of leaves in June and July，to postpone harvesting is beneficial to enhance the kernel’s output and the fat content． ［Ch，1 fig. 3 tab. 21 ref.］
Carya cathayensis is famous because its nut has rich nutrition，especially in oil and protein. We explore the nut’s growth process in order to obtain the law of oil accumulation. From May to September in 2006，we picked 150－300 nuts from 6 sample trees each 7－10 days. Then，we determine its diameter，fresh and dry weight，the weight rate of kernel to shell，crude protein，soluble sugar，and crude fat. Results showed that development of the Carya cathayensis nut throughout its growing season is divided into two distinct phases. Phase Ⅰ occurred from early May to early August. During this phase the C. cathayensis nut enlarged with the fastest growth in June and July and came to full size. Phase Ⅱ occurred from early August until harvest in early September，wherein the kernel developed and filled out with nutrients accumulating and transforming. In this phase，significant negative correlations were found between crude protein and crude fat （r =－0.991 3，P＜0.01） and between soluble sugar and crude fat （r = －0.956 5，P＜0.01）with protein content decreasing from 117.4 to 93.6 mg·g－1，soluble sugar decreasing from 56.1 to 19.67 mg·g－1，and crude fat continuously increasing from 33.9% to 69.0%. So we should provide adequate nutrition to maintain the vitality of leaves in June and July，to postpone harvesting is beneficial to enhance the kernel’s output and the fat content． ［Ch，1 fig. 3 tab. 21 ref.］
2008, 25(4): 532-537.
Abstract:
Total DNA was extracted from young，fully opened leaves of Carya cathayensis（hickory） by an improved cetyl trimethylammonium bromide（CTAB） method and a CTAB-silicon method，based on which an amplified fragment length polymorphism（AFLP）analysis system for hickory was developed. An electrophoresis was used on the amplified products in a 6% denatured polyacrylamide gel，followed by silver staining，with clearly identified bands shown. Specifically：（1）the improved CTAB method was appropriate for DNA extraction from hickory leaves with extracted DNA qualified for AFLP analysis；（2）with a combi-nation of EcoRⅠand MseⅠfor enzyme cutting，the results were the same for the one-step method combining enzyme cutting and adaptor ligation and the two-step method which separated them with the one-step method being much easier；and （3）there were four primer pairs suitable for this AFLP analysis，namely E-ACT + M-CAT，E-ACG + M-CAT，E-ACG + M-CAT，and E-ACG + M-ATG. ［Ch，6 fig. 3 tab. 17 ref.］
Total DNA was extracted from young，fully opened leaves of Carya cathayensis（hickory） by an improved cetyl trimethylammonium bromide（CTAB） method and a CTAB-silicon method，based on which an amplified fragment length polymorphism（AFLP）analysis system for hickory was developed. An electrophoresis was used on the amplified products in a 6% denatured polyacrylamide gel，followed by silver staining，with clearly identified bands shown. Specifically：（1）the improved CTAB method was appropriate for DNA extraction from hickory leaves with extracted DNA qualified for AFLP analysis；（2）with a combi-nation of EcoRⅠand MseⅠfor enzyme cutting，the results were the same for the one-step method combining enzyme cutting and adaptor ligation and the two-step method which separated them with the one-step method being much easier；and （3）there were four primer pairs suitable for this AFLP analysis，namely E-ACT + M-CAT，E-ACG + M-CAT，E-ACG + M-CAT，and E-ACG + M-ATG. ［Ch，6 fig. 3 tab. 17 ref.］
2008, 25(4): 538-542.
Abstract:
Populus tomentosa is the main tree species for afforestation in north China. To maintain its productivity，annual changes in leaf nutrient concentrations of N，P，K，Ca，and Mg with 11 clones of triploid P. tomentosa （S1 through S9，S11，and S12） were studied with diploid P. tomentosa （S10） as a control. The one-year-old seedlings were afforested in 2005，in Pinggu of Beijing，and leaves were gathered respectively in April，July and October of 2006 by representative sampling method with three replications，for determining N，P，K，Ca，and Mg concentrations in leaves. Results showed that （1） for a given nutrient，triploid P. tomentosa leaves had similar seasonal variations，N，P，and K，levels declined during the whole growth period；Ca gradually increased，while Mg increased and then decreased. Also，（2） greater P concentrations in leaves of different clones were highly significant（P＜0.01，n = 36）with the greatest being 1.85 g·kg－1 in S5. Additionally，（3） compared to diploid P. tomentosa，throughout the growing season，P concentrations in leaves of triploid P. tomentosa increased for clones S1，S3 through S7，and S12. Finally，（4） during the growing season，for the different clones of P. tomentosa，concentrations of these macro elements were similar with the order and average content （in g·kg－1） of the five nutrients as：N（24.31）＞K（17.23）＞Ca（4.36）＞Mg（1.94）＞P（1.56）. ［Ch，5 fig. 2 tab. 8 ref.］
Populus tomentosa is the main tree species for afforestation in north China. To maintain its productivity，annual changes in leaf nutrient concentrations of N，P，K，Ca，and Mg with 11 clones of triploid P. tomentosa （S1 through S9，S11，and S12） were studied with diploid P. tomentosa （S10） as a control. The one-year-old seedlings were afforested in 2005，in Pinggu of Beijing，and leaves were gathered respectively in April，July and October of 2006 by representative sampling method with three replications，for determining N，P，K，Ca，and Mg concentrations in leaves. Results showed that （1） for a given nutrient，triploid P. tomentosa leaves had similar seasonal variations，N，P，and K，levels declined during the whole growth period；Ca gradually increased，while Mg increased and then decreased. Also，（2） greater P concentrations in leaves of different clones were highly significant（P＜0.01，n = 36）with the greatest being 1.85 g·kg－1 in S5. Additionally，（3） compared to diploid P. tomentosa，throughout the growing season，P concentrations in leaves of triploid P. tomentosa increased for clones S1，S3 through S7，and S12. Finally，（4） during the growing season，for the different clones of P. tomentosa，concentrations of these macro elements were similar with the order and average content （in g·kg－1） of the five nutrients as：N（24.31）＞K（17.23）＞Ca（4.36）＞Mg（1.94）＞P（1.56）. ［Ch，5 fig. 2 tab. 8 ref.］
