2022 Vol. 35, No. 1
2022, 35(1): 0-0.
[Abstract](1194) [FullText HTML] (796) [PDF 67206KB](63) [Cited by] ()
2022, 35(1): 0-1.
[Abstract](991) [FullText HTML] (806) [PDF 269KB](40) [Cited by] ()
Response of Individual Height of Larix principis-rupprechtii Plantation to Site Factors and Stand Characteristics in Liupan Mountain Area
2022, 35(1): 1-9. doi: 10.13275/j.cnki.lykxyj.2022.01.001
[Abstract](3424) [FullText HTML] (2161) [PDF 1157KB](97) [Cited by] ()
Objective For the main afforestation species of Larix principis-rupprechtii in the forest area of Liupan Mountains, To study the response of individual tree height in Larix principis-rupprechtii, the main afforestation species in the forest area of Liupan Mountain Area, to site conditions and stand structure, in order to predict tree height growth more accurately, and to determine the suitable site for afforestation and proper stand structure for forest management, so as to guide the accurate and precise management of stand structure. Method The tree height growth data of L. principis-rupprechtii were obtained by carrying out the survey of analytic trees of various dominances in selected typical plots with various site conditions and stand structure characters, and the response law and suitable function forms of tree height response to all single factors were determined by the upper boundary line method. Then the tree height growth model which can reflect the influence of multiple factors was formed by a continuous multiplication. The model parameters were fitted using the measured data for getting the optimal tree height growth model. Result (1) The growth process of individual tree height of L. principis-rupprechtii showed a "S" curve. (2) Correlation analysis showed that the influence on tree height growth by the factors except tree age followed the order of elevation > canopy density > tree dominance > stand density > slope aspect > slope. (3) The most suitable conditions for the height growth of L. principis-rupprechtii are the elevation range of 2 000−2 400 m, the slope aspect range from shade slope to half shade slope, the slope gradient range of 20°−225°, the canopy density range of 0.49−20.64, the stand density of 1100−21300 trees/hm2. In addition, the height of individual trees increased with rising tree dominance but with a leveling-off increase rate after the dominance is higher than 0.2. (4) The height growth model of individual trees was established by coupling the response functions to the main influencing factors, with a satisfactory fitness. Conclusion The individual tree height growth of L. principis-rupprechtii is affected by both site conditions and stand structure characteristics. The main influencing factors are tree age, elevation, canopy density, and tree dominance. When considering the influencing factors, the coupled model of individual tree height growth can predict the spatio-temporal variation of individual tree height more accurately, and benefit the rational management of L. principis-rupprechtii plantation.
Transformation of Eucalyptus urophylla × Eucalyptus grandis Clone Plantation into Mixed-species Forest Using Precious Tree Species
2022, 35(1): 10-19. doi: 10.13275/j.cnki.lykxyj.2022.01.002
[Abstract](2940) [FullText HTML] (1458) [PDF 849KB](90) [Cited by] ()
Objective To discuss the mixed forest model of interplanting precious tree species under Eucalyptus urophylla × Eucalyptus grandis clone plantation with different cutting intensity and analyze the change trend of stand growth and understory vegetation diversity of mixed forest after interplanting, in order to provide a theoretical basis for the transformation of E. urophylla × E. grandis clone plantation into mixed forest of Eucalyptus and precious tree species. Method According to the split plot experimental design, the transformation experiment of 9-year-old E. urophylla × E. grandis clone plantation in State-owned Dongmen Forest Farm was carried out with precious tree species. Four cutting treatments were set in the main area: A: cutting 1 row every other row (1 E. urophylla × E. grandis + 1 precious species trees; B: cutting 2 rows every other 2 rows (2 E. urophylla × E. grandis + 2 precious species trees); C: cutting 2 rows every other 3 rows (3 E. urophylla × E. grandis + 2 precious species trees); D: cutting 3 rows every other 2 rows (2 E. urophylla × E. grandis + 3 precious species trees); six tree species were used for interplanting, i.e. Castanopsis hystrix Hook. f. & Thomson ex A. DC., Erythrophleum fordii Oliv., Manglietia conifera Dandy, Acacia melanoxylon R. Br., Dalbergia cochinchinensis Pierre ex Laness, and Aquilaria sinensis (Lour.) Spreng., and the control plot without transformation was set up. Each tree in the test area was measured, and the understory vegetation was investigated according to the conventional method at the age of 3.5 years after interplanting. Result The average tree height, DBH and individual volume of E. urophylla × E. grandis increased significantly under different mixed forest models, with the highest values of 27.63 m, 21.89 cm and 0.38 m3 respectively, which increased by 16.98%, 19.75% and 80.96% compared with the CK. The growth indexes of C. hystrix were the best among the interplanting species, followed by Manglietia conifera and Acacia melanoxylon. The volume of E. urophylla × E. grandis plantation interplanting Acacia melanoxylon in 3 Eucalyptus + 2 precious species trees was the best, reaching 244.87 m3·hm−2, which was 3.65% higher than CK. In addition, the Simpson indexes of herb layer of 2 Eucalyptus and 2 precious trees and the Shannon-Winner index of herb layer of 3 Eucalyptus and 2 precious species trees interplanting C. hystrix were 0.84 and 1.71 respectively, which were 25.40% and 30.50% higher than that of the CK; while the Simpson index and Shannon-Winner index of shrub layer in the stand with interplanting of D. cochinchinensis were 0.80 and 1.61, respectively, which were 42.9% and 71.27% higher than that of the CK. Conclusion In this study, the precious tree species were used to transform E. urophylla × E. grandis clone plantation to form a Eucalyptus and precious trees multi-layer mixed forest, which significantly improved the average tree height, DBH and single tree volume, optimized the stand structure, enriched the species diversity of the stand, changed the landscape of a single forest phase of E. urophylla × E. grandis and helped to improve the ecological and economic benefits of E. urophylla × E. grandis clone plantation. The results may provide scientific and technological support for the cultivation of medium- and large-diameter Eucalyptus and the management of national reserve forest.
Variation and Selection of Seedling Growth Traits Among Juglans mandshurica Provenances and Families
2022, 35(1): 20-30. doi: 10.13275/j.cnki.lykxyj.2022.01.003
[Abstract](3673) [FullText HTML] (1771) [PDF 638KB](60) [Cited by] ()
Objective To analyze and select the genetic variation of growth traits among provenances and families of Juglans mandshurica, in order to promote the selection and breeding of J. mandshurica superior varieties. Method In this study, the growth characteristics (tree height, annual growth of tree height, ground diameter, crown width, straightness, branch angle, number of side branches and taperingness) of 28 J. mandshurica families (6-years-old) within 4 provenances at Wanrenhuan Forest Farm were measured and analyzed. Result The results of analysis of variance showed that most of the traits reached extremely significant differences among various sources (P < 0.01). The phenotypic and genetic coefficient of variation of these traits ranged from 14.049% to 41.519% and from 8.754% to 23.873%, respectively. The family heritability and individual heritability were ranged from 0.284 to 0.797 and from 0.110 to 0.886, respectively. The results of correlation analysis showed that the correlation of almost all traits reached a significant level (P < 0.05), except the correlations between sharpness and branch angle, between sharpness and number of side branches, and between straightness and crown width. The results of general combining ability analysis showed that with a selection rate of 20%, 6 excellent parents were screened according to different traits. The results of principal component analysis (PCA) showed that the cumulative contribution rate of the three principal components reached 73.264%, indicating that the three principal components contained most information of the measured trait. According to the comprehensive scores of PCA, one excellent provenance, three excellent families and 10 excellent individual plants were initially selected. The realistic gains of tree height, average annual increase in tree height, ground diameter and crown width of selected provenance were 3.109%, 5.014%, 2.193%, and 1.040%, respectively. The genetic gains of the 4 traits of the families selected were 5.835%, 5.410%, 7.908%, and 6.069%, respectively. The genetic gains of the 4 traits of selected individuals were 26.74%, 24.11%, 23.91% and 26.53%, respectively. Conclusion The growth traits of J. mandshurica have rich variations within provenances and families. The excellent provenances, parents, families and individuals preliminary selected could lay a basis for the selection and application of J. mandshurica varieties.
2022, 35(1): 31-39. doi: 10.13275/j.cnki.lykxyj.2022.01.004
[Abstract](2965) [FullText HTML] (1823) [PDF 929KB](64) [Cited by] ()
Objective To study the influnence of resin-tapping duration on the basic density and lignin content of resin-tapping parts and trunk of Pinus elliottii in order to optimize the genetic improvement and resource utilization of P. elliottii. Method Twenty-years-old P. elliottii trees that have been resin-tapped for 8, 6, 3, and 0 years were studied using Resistograph technology to measure the relative value of density and width of tree in the resin-tapping part and the base of the trunk. The wood core was extracted from the same plant by electric growth cone drill and the sawdust was collected. The basic density of wood was determined by submerged water method and the lignin content was determined by Reagent test kit. The correlation around basic density, lignin content and the Resistograph was analyzed. Result The correlation coefficients between the basic density of P. elliottii wood and the Resistograph values after 8, 6, 3 and 0 years of resin-tapping were 0.45, 0.39, 0.50 and 0.63, respectively. The linear regression equations for predicting the basic density of wood using Resistograph values were established. There was no significant correlation between lignin content and Resistograph values (P > 0.05). The base density of the tree trunk of P. elliottii after 3 years of resin-tapping was significantly higher than that after 0, 6 and 8 years of resin-tapping, and the base density of the tree trunk after 6 and 8 years of resin-tapping was significantly lower than that of the tree trunk without resin-tapping, but there was no significant difference between the base density of the tree trunk after 6 and 8 years of resin-tapping. The basic density of P. elliottii after 3 years of resin-tapping was significantly higher than that after 0 and 6 years of resin-tapping, but there was no difference with that after 8 years of resin-tapping. There was no significant difference among the basic density after 0, 6 and 8 years of resin-tapping. The analysis results of lignin content showed that the lignin content in the base of the tree trunk was lower than that after 0, 3 and 8 years of resin-tapping, and there was no significant difference in the rest, but the lignin content in the base of the tree trunk was lower after 6 years of resin-tapping than that after the other three durations. Conclusion Resistograph determination is suitable for predicting the basic density of P. elliottii after resin-tapping, but not for lignin content. To a certain extent, the basic density of P. elliottii at the base and site of tree trunk will increase in initial and then decrease, and the lignin content at the site of tree trunk will decrease in initial and then increase, but shows no effect on the lignin content at the base of tree trunk. When the resin is harvested over a certain years, the basic density of the resin-tapping part will be higher than that of the base of tree trunk, but the lignin content of the two parts is not affected.
Characteristics of Particulate Organic Carbon and Nitrogen in Soil of Leucaena leucocephala Plantation in the Dry-hot Valley
2022, 35(1): 40-47. doi: 10.13275/j.cnki.lykxyj.2022.01.005
[Abstract](2762) [FullText HTML] (1748) [PDF 900KB](39) [Cited by] ()
Objective To investigate the change characteristics of soil particulate carbon and nitrogen content in the process of plantation restoration and to provide references for studying the response mechanism of soil carbon and nitrogen dynamics to plantation restoration. Method Leucaena leucocephala plantations at young age, middle age and matured age in Yuanmou dry-hot valley were selected and the natural shrub-grass plot as the control, the change characteristics of the soil particulate carbon and nitrogen content of natural shrub-grass plot and L. leucocephala plantations with different ages were studied. Result Compared with the natural shrub-grass plot, the age stage of L. leucocephala plantations significantly affected the soil organic carbon (SOC), total nitrogen (TN), particulate organic carbon (POC), particulate organic nitrogen (PON), POC/SOC, POC/PON. The proportion of mass of soil particle, SOC and TN contents were the highest in the matured plantation, while the POC, PON, POC/SOC, and POC/PON were the highest in the middle aged plantation. Conclusion The invasion of L. leucocephala into shrubs in dry-hot valley will significantly change the dynamics of soil carbon and nitrogen and its stability. The soil nutrient content in the matured plantation is the highest, while the soil stability in the middle-aged plantation is the lowest. This study could provide data support for the comprehensive evaluation of the effect of L. leucocephala on improving the soil ecological function in dry-hot valley.
2022, 35(1): 48-58. doi: 10.13275/j.cnki.lykxyj.2022.01.006
[Abstract](2358) [FullText HTML] (1529) [PDF 1092KB](77) [Cited by] ()
Objective Taking healthy and dead Pinus massoniana Lamb. in Bursaphelenchus xylophilus infected area in Zhejiang province as research object to examine the differences in the microbial communities structure of P. massoniana trees before and after infected by B. xylophilus, and to accumulate the microbial resources for controlling pine wilt disease by using endophytic microorganisms of P. massoniana. Method The methods of tissue isolation, morphology and molecular biology were used to isolate and identify the fungi and bacteria in different tissues (root, stem and needle) of healthy and dead P. massoniana. Phylogenetic tree was constructed for the isolated Trichoderma strains, and the effect of Trichoderma spp. on B. xylophilus population was analyzed by feeding experiments. Result 106 fungal strains belonging to 19 genera were isolated from healthy P. massoniana, and 86 strains belonging to 10 genera were isolated from the dead pine, the dominant genera were both Trichoderma. There were differences in fungal diversity among different tissues, the diversity indexes of stem and needle were higher than those of root. The Shannon-Wiener index, Simpson index and evenness index of fungal community from healthy pine were 2.37, 0.87 and 0.51, respectively, they were all higher than those of dead pine, which were 1.72, 0.76 and 0.39. The similarity indexes of fungal community in healthy and dead P. massoniana were less than 0.5. 59 bacterial strains belonging to 13 genera were isolated from healthy P. massoniana, and 56 strains belonging to 12 genera were isolated from the dead pine, the dominant groups were Burkholderia, Enterobacter and Serratia. The bacterial diversity of stem was the highest in both the healthy and dead pine, and that of needle was the lowest. The similarity indexes of bacterial community in healthy and dead P. massoniana were more than 0.5. Trichoderma was the dominant group in P. massoniana, six species were isolated in this study. The feeding experiment showed that the sample FXY7 of Trichoderma significantly inhibited the population of B. xylophilus. Conclusion The fungal diversity in healthy P. massoniana is higher than that in dead P. massoniana, the similarity of fungal community between healthy and dead pine is low, and the similarity of fungal community among different tissues is also low. However, the bacterial communities of healthy and dead pine are similar to some extents. This indicates that the invasion of B. xylophilus will affect the fungal community diversity in P. massoniana, but there is a little effect on the bacterial community. In addition, a number of endophytic bacteria with bio-control potential against pine wilt disease were isolated in this study, which is helpful for exploring prevention and control technology of pine wilt disease.
Effects of Photoperiod and Light Quality on Seedling Growth and Chlorophyll Fluorescence Kinetics of Quercus L.
2022, 35(1): 59-69. doi: 10.13275/j.cnki.lykxyj.2022.01.007
[Abstract](1852) [FullText HTML] (1033) [PDF 999KB](51) [Cited by] ()
Objective To study the growth and photochemical mechanism of leaves in Quercus L. seedlings responding to photoperiod and light quality in order to provide reference for seedling cultivation and artificial assisted regeneration of Quercus L. Method The growth parameter and chlorophyll fluorescence parameters of Quercus spp. seedlings (3 Q. variabilis provenances + 1 Q. mongolica + 1 Q. glandulifera) under three photoperiods (the lengths of light and dark were 10 h/14 h, 14 h/10 h, 18 h/6 h, respectively) and three red - far red light ratios (R : FR = 0.83 ± 0.04, 1.37 ± 0.04, 4.69 ± 0.04, respectively) were investigated. Result (1) At the species' level, the Fv/Fo, Fv/Fm, Ψo, φEo and PIAbs increased, while Mo, Vi, Vj, ABS/RC, DIo/RC and φDo decreased with the prolonging of photoperiod. Specially, Mo, Vi and Vj of Q. variabilis seedlings were the highest, Ψo and φEo were the lowest under medium photoperiod. Q. glandulifera and Q. variabilis showed a stronger response to photoperiod than Q. mongolica. The shortening photoperiod would significantly reduce the Fv/Fm and relative growth rate (RGR) of Q. glandulifera, and the prolonging photoperiod would significantly improve the RGR of Q. glandulifera and Q. variabilis, but the Fv/Fm and RGR of Q. mongolica showed no significant response to photoperiod changes. At the intra-species level, long photoperiod significantly increased the Fv/Fo and Fv/Fm of the Yunnan provenance and the RGR of all the three provenances of Q. variabilis increased with photoperiod. (2) Light quality ratio had no significant effects on RGR, energy allocation parameters and quantum yield parameters among three Quercus species and different provenances of Q. variabilis. (3) The significantly interactive effects between light quality ratio and photoperiod on RGR were observed. Under medium photoperiod, the seedlings showed an obvious shade-avoidance response, namely, the RGR of seedlings with low light quality ratio was the highest, which was significantly higher than that in the normal and high light quality ratio. Conclusion The results show that there are intraspecific and interspecific differences in response to photoperiod and light quality ratio. The south provenance of Q. variabilis are more sensitive to photoperiod. Q. glandulifera and Q. variabilis have a stronger response to photoperiod than Q. mongolica. Light quality ratio generally has no significant effects among Quercus L. seedlings. The seedlings show obvious shade-avoidance responses only under specific photoperiod.
Comprehensive Evaluation of Fruit Phenotype and Quality of Main Chinese Chestnut Cultivars in the Middle and Lower Reaches of the Yangtze River
2022, 35(1): 70-81. doi: 10.13275/j.cnki.lykxyj.2022.01.008
[Abstract](2610) [FullText HTML] (1871) [PDF 838KB](36) [Cited by] ()
Objective To evaluate the fruit traits of main Chinese chestnut (Castanea mollissima) cultivars from the middle and lower reaches of the Yangtze River and provide references for the selection of chestnut cultivars with excellent comprehensive performance and suitable for planting and promoting in Zhejiang Province. Method Twenty-five main Chinese chestnut cultivars in the middle and lower reaches of the Yangtze River and five representative northern Chinese chestnut cultivars were used as materials, their fruit phenotype and quality traits were continuously measured and statistically analyzed. Then comprehensive evaluation was performed by principal component analysis and grey correlation analysis. Result Twenty traits of fruit phenotype and quality had different degrees of variation, and the coefficient of variation ranged from 7.85% to 41.20%. There were 23 pairs and 18 pairs of correlation among all traits reached extremely significant (P<0.01) and significant level (P<0.05), respectively. There was a certain correlation between the fruit phenotype and the quality traits. The cumulative contribution rate of the top five principal components was 79.25%, which retained most of the information of fruit phenotype and quality traits. Grey correlation analysis showed that there were significant differences in the weight values of each trait, in which the weight coefficient of potassium content was the largest and the weight coefficient of total flavonoids content was the smallest. The overall trend of the comprehensive performance ranking of the 30 Chinese chestnut cultivars performed by the two analysis methods was relatively consistent. The correlation coefficient of the comprehensive score of the cultivars by the two analysis was 0.7621, which reached a very significant level. Conclusion Six Chinese chestnut cultivars from the middle and lower reaches of the Yangtze River are ranked in the top by the two analysis, the comprehensive performance of their fruit traits is excellent, so the six cultivars can be popularized as the main cultivar in Zhejiang Province.
2022, 35(1): 82-91. doi: 10.13275/j.cnki.lykxyj.2022.01.009
[Abstract](4105) [FullText HTML] (1777) [PDF 1934KB](48) [Cited by] ()
Objective To clone the CUC1 gene of Fraxinus mandshurica and analyze its expression characteristics, so as to lay a foundation for the regulation of the gene in the regeneration of F. mandshurica Method The FmCUC1 gene was cloned from F. mandshurica seedlings. The nucleotide sequence of FmCUC1 gene and the amino acid sequence of its coding protein were analyzed by bioinformatics software, and the phylogenetic tree was constructed. The FmCUC1 gene was transferred into onion inner epidermis cells by Agrobacterium tumefaciens infection method for subcellular localization. The tissue surface of FmCUC1 gene in root, stem, leaf and apical bud was analyzed by real-time fluorescence quantitative analysis. At the same time, the seedlings of F. mandshurica were sprayed with IAA, 6-BA and BR hormones to analyze the expression pattern of FmCUC1 gene induced by different hormone signals; the FmCUC1 gene was transiently transformed into F. mandshurica by A. tumefaciens for 72 hours. Result The full length of FmCUC1 gene was 807 bp, encoding 269 amino acids. FmCUC1 was a stable hydrophobic protein with a conserved NAC domain protein domain. The sequence similarity of FmCUC1 protein and Olea europaea subsp. europaea protein was 86.17%, which was close to each other. FmCUC1 protein was located in the nucleus. q-RT PCR analysis showed that the expression of FmCUC1 gene was the highest in the terminal bud of F. mandshurica; during hypocotyl bud regeneration, the expression of FmCUC1 gene was high in both bud point formation and clump formation; during seed germination, the expression of FmCUC1 gene reached two peaks on the 4th and 8th day, which were 8.56 and 8.46 times of that on the first day. The results of exogenous spraying IAA, 6-BA and BR showed that the expression of FmCUC1 gene was up-regulated compared with the control, and reached the highest value after 72 h of IAA and BR treatment, which were 45.72 times and 20.36 times of the control, respectively, and reached the peak value after 48 h of 6-BA treatment, which was 59.40 times of the control. Agrobacterium tumefaciens mediated transient overexpression of FmCUC1 gene for 72 hours, the expression of FmCUC1 gene and its downstream STM gene increased significantly. Conclusion FmCUC1 gene belongs to NAC family and is a nuclear transcription factor. It participates in the process of shoot regeneration of F. mandshurica, and responds to the induction of IAA, 6-BA and BR plant hormone signals. Overexpression of FmCUC1 gene can activate the expression of its downstream STM gene, which is conducive to the formation of apical meristem.
2022, 35(1): 92-96. doi: 10.13275/j.cnki.lykxyj.2022.01.010
[Abstract](2781) [FullText HTML] (1762) [PDF 581KB](16) [Cited by] ()
Objective To investigate the absorption and transformation of sulfur dioxide in the air by three poplar varieties in order to study the mechanism of sulfur dioxide resistance and the capacity of Populus × euramericana cv. 'Purui' in purifying the atmosphere. Method Three poplar varieties (Populus × euramericana cv. 'Purui' (Purui), Populus × euramericana cv. '74/76' (107) and Populus × euramericana cl. 'Zhonglin 46' (Zhonglin 46)) were selected to compare their effects on absorbing and purifying the sulfur dioxide in atmosphere. The diurnal dynamic changes of sulfur dioxide concentration in the air inside and outside the forests were measured. The concentrations of sulfate (SO42-) in the leaves of Purui, Zhonglin 46 and 107 under different sulfur dioxide pollution environments were measured. Result The daily dynamic changes of sulfur dioxide concentration inside and outside the forests indicated that the three poplar varieties were able to absorb sulfur dioxide, and hence purify the air. Among them, Purui had significantly greater capacity in sulfur dioxide absorption and air purification than Zhonglin 46 and 107. Sulfate ion concentration in Purui leaves was significantly higher than that in Zhonglin 46 and 107. Whether in the environment of high or low concentration of sulfur dioxide, the sulfate ion in the leaves of Purui was higher than that of the other two varieties, indicating that Purui had stronger ability to absorb sulfur dioxide and convert it into non-toxic sulfur compounds. This is also an important mechanism of sulfur dioxide resistance for Purui. Conclusion Among the three poplar varieties, Purui has stronger ability to purify the atmosphere polluted by sulfur dioxide, thereby detoxifying sulfur dioxide, so as to better purify the air and reduce the harm of haze to human body. Compared with other poplar species, Purui has stronger ability to convert sulfur dioxide into non-toxic sulfate ions, which can facilitates its detoxification.
2022, 35(1): 97-103. doi: 10.13275/j.cnki.lykxyj.2022.01.011
[Abstract](2747) [FullText HTML] (2741) [PDF 1102KB](33) [Cited by] ()
Objective To study the distribution of fallen wood and the impact of fallen wood on forest regeneration of Saihanwula forest ecosystem,a typical area of Hanshan Mountains secondary forests locating at the southern parts of Daxing'anling Mountains,Inner Mongolia. Method The sample plot survey method was used to investigate the fallen wood and forest regeneration. Result The regeneration density of the fallen wood plot was 4 050±824 plants·hm−2, the regeneration density of the standing wood plot was 2 950±265 plants·hm−2, the regeneration density of the control plot was 2 625±237 plants·hm−2; the average reserve of the fallen wood in Saihanwula was 58.51±16.56 m3·hm−2. Among them, the distribution densities of the fallen wood for decomposition grades II, III, IV, and V were 50±21, 806±198, 189±76, and 22±5 plants·hm−2. The fallen logs in the study area mainly existed in the form of "trunk base fracture", accounting for 68.78% of the total number of fallen logs. Conclusion A large amount of fallen wood accumulates in the forest, which has the effect of obstructing, intercepting and shading the renewal of seeds, seedlings, saplings, etc. At the same time, the fallen wood will severely crush the renewed seedlings and other plants under the forest at the moment of dumping and for a long time after dumping. Negative effects such as crushing injuries, the rate of crushing injuries is 5.3% ～ 7.8%. However, the proper amount of fallen trees with high decomposition levels can promote the growth of seedlings and young trees, and the rational use of the relationship between fallen trees and forest regeneration can effectively promote the healthy development of forests.
Prediction of Potential Distribution of Endangered Species Corylus chinensis Franch. in Climate Change Context
2022, 35(1): 104-114. doi: 10.13275/j.cnki.lykxyj.2022.01.012
[Abstract](2724) [FullText HTML] (1859) [PDF 1336KB](58) [Cited by] ()
Objective To explore the change trend of the geographical distribution pattern of Corylus chinensis with climate, divide the suitable areas and provide references for the protection and utilization of C. chinensis. Method Based on 83 modern distribution records of C. chinensis and the screened data of 18 environmental variables, the maximum entropy model (MaxEnt) in the species distribution model was used to simulate the potential distribution areas of C. chinensis in six periods since the last interglacial period. Result The results of the area under receiver operating curve (AUC) show that the simulation results are more accurate, and temperature is an important factor affecting the geographical distribution of C. chinensis in six different periods. During the last interglacial period, the total suitable area of C. chinensis decreased by about 9% compared with modern times, and there was little change during the last glacial maximum period. The total suitable area increased by 4.4% compared with modern times in the middle Holocene. It is predicted that the suitable area will increase in 2050s and 2070s. The distribution centers of C. chinensis in different periods are all located in Hubei Province. In the future, the distribution center will show a tendency to migrate to high latitudes under the condition of future climate warming. From the perspective of the suitable area, C. chinensis shows a shrinking trend in the glacial period, and shows an expansion trend in the mid-Holocene and future global warming scenarios. Conclusion The distribution area of C. chinensis suitable for climate change is different. Temperature is the main factor affecting its distribution. Under the condition of climate warming in the future, the distribution center will migrate to high latitude.
2022, 35(1): 115-122. doi: 10.13275/j.cnki.lykxyj.2022.01.013
[Abstract](2475) [FullText HTML] (1506) [PDF 814KB](29) [Cited by] ()
Objective To find the best band combination of GF6 image data for the identification of vegetation types, especially wetland vegetation information, so as to provide reference for the further application of GF6 data in wetland resources monitoring. Method Taking Sanjiang Nature Reserve as example and basd on the GF6 data, the research mentioned above was conducted combing with the features of local vegetation. From the perspective of image information characteristics, the best index factor, the spectral characteristic curve and the separability of ground objects, the best band combination for vegetation type identification in Sanjiang Nature Reserve based on GF6 data were obtained. At the same time, through comparative experiment, the support vector machine classification method was used to extract the vegetation type information of the sample area, and the reliability of the results was confirmed. Result The band combination of 1-4-5 showed the highest accuracy in vegetation classification with 89.15% overall accuracy and 0.8463 Kappa coefficient. Conclusion The band combination of 4(R)-5(G)-1(B) is the optimal band combination for vegetation classification in Sanjiang Nature Reserve. This study can provide a reference for monitoring the returning farmland to wetland project in northeast China.
Selection and Validation of Reference Genes for Leaf Color Phenotype in 'Maiyuanjinqiu', a Catalpa fargesii Variety, by qRT-PCR
2022, 35(1): 123-131. doi: 10.13275/j.cnki.lykxyj.2022.01.014
[Abstract](2820) [FullText HTML] (1853) [PDF 1035KB](58) [Cited by] ()
Objective To select the housekeeping genes stably expressed in leaves in order to support the study of the molecular mechanism of leaf color formation on 'Maiyuanjinqiu', a Catalpa fargesii variety. Method The relative expression of seven candidate genes, including CfUBC, CfActin11, CfPP2A, CfMADH, CfGADPH, CfEF-1 and CbuActin were detected by real-time quantitative PCR (qRT-PCR) technology using leaves of different leaf color sectors of 'Maiyuanjinqiu' and the corresponding sectors of Catalpa fargesii Bur. The stability of the seven candidate reference genes was evaluated by using internal reference analysis software such as GeNorm, NormFinder and BestKeeper. Furthermore, the expression patterns of terpenoid biosynthesis related gene (CfGES) in the leaves of different leaf color parts of 'Maiyuanjinqiu' and the corresponding sectors of C. fargesii were analyzed respectively. The results verified the stability evaluation results mentioned above. Result All the seven candidate reference genes can be used as internal reference genes in the leaves of 'Maiyuanjinqiu' and C. fargesii. The expression levels of CfMADH and CfEF-1 were the most stable in different color tissues, followed by CfGADPH and CfActin11, while the CfUBC was the worst. The stability of internal reference gene was verified by terpenoid biosynthesis related gene (CfGES). It was found that the expressions of CfGES gene were consistent with the trend of transcriptome data, when CfEF-1 and CfMADH genes were used as internal reference for qRT-PCR alone or in combination. Conclusion Using CfMADH and CfEF-1 individually or in combination to calibrate the gene expression levels of different leaf color parts in 'Maiyuanjinqiu' can greatly improve the reliability of experimental results.
2022, 35(1): 132-140. doi: 10.13275/j.cnki.lykxyj.2022.01.015
[Abstract](3245) [FullText HTML] (1281) [PDF 802KB](50) [Cited by] ()
Objective To identify and analyze the floral volatile components of Dendrobium, a medical herb commonly used in China. Method The floral volatile components of Dendrobium pendulum Roxb., D. findlayanum Par. ex Rchb. f., D. crepidatum Lindl. ex Paxt., D. chrysanthum Lindl. and D. primulinum Lindl. were qualitatively analyzed by HS-SPME and GC-MS. Result A total of 110 volatile components were identified from the flowers, the main components were alcohols, alkanes, alkenes and ketones. For the first time, the fragrance components were analyzed in fresh flowers of D. pendulum, D. findlayanum, D. crepidatum, and D. chrysanthum. Conclusion The aroma components of fresh flowers are different among Dendrobium species. The aroma components in D. findlayanum are basilene and β-caryophyllene, that in D. chrysanthum are basilene, pinene and linalool, that in D. pendulum are linalool, luollene and β-caryophyllene, that in D. crepidatum are d-limonene, pinene and luollene. Both D. findlayanum and D. pendulum contain β-caryophyllene, a substance with the effect of anti- depression.
Analysis of Endogenous Hormones and Transcriptome in Sophora japonica Infected with Fasciation Disease
2022, 35(1): 141-149. doi: 10.13275/j.cnki.lykxyj.2022.01.016
[Abstract](1986) [FullText HTML] (1040) [PDF 1032KB](34) [Cited by] ()
Objective To investigate the pathogenesis of banding disease of Sophora japonica, so as to provide data for the prevention and control of the disease. Method In this study, the contents of auxin, zeatin, gibberellin and abscisic acid in the healthy and diseased branches of Sophora japonica were determined continuously in May, August, September and November. The differentially expressed genes were screened by transcriptome sequencing and the qPCR analysis was performed. Result In May, August, September and November, the contents of auxin, zeatin, gibberellin and abscisic acid in healthy tree, infected and symptomless shoots of the diseased trees were basically the same, but during the vigorous growth period of S. japonica in August, the content of zeatin in the infected branches was significantly higher than that in the healthy control; the contents of auxin and gibberellin were significantly lower than that of the healthy control. However, in the late growth stage of the plants in November, only the abscisic acid content of the diseased plants was significantly higher than that of the healthy control. Transcriptome sequencing results showed that the down-regulation of differential genes was significantly higher than up-regulation, and GO functional annotation analysis of differential genes showed that the differential genes were mainly concentrated in cell component, molecular function and biological process, especially in cell component and molecular function, while the KEGG metabolic pathway analysis showed that the differentially expressed genes in susceptible plants were mainly concentrated in signal transduction, plant pathogen interaction and plant hormone signal transduction. The results of endogenous hormone metabolic pathway annotation showed that AUX1 and CRE were down regulated, while the TF and ABF were up-regulated. The genes (GHLAX5, GHAHK4, GHAHP4,GHARR8, GHTF and GHABF2) regulating auxin, zeatin, gibberellin and abscisic acid metabolism and signal transduction were obtained by screening the transcriptome data for qPCR verification. Although there were some differences between the results and the transcriptome data, the expression trend was basically the same. These results suggested that the differential expression of these genes may play an important role in regulating the endogenous hormone content of S. japonica. Conclusion The significant increase of zeatin content and the significant decrease of auxin and gibberellin contents may hinder the immune response of plants and the differential expression of key genes regulating the metabolism of these three hormones, which may be the main reason for the occurrence and lateral growth of the diseased branches of S. japonica.
Effects of Interspecific Relationship on Natural Regeneration and Community Stability of Pinus tabuliformis Plantation in Zhongtiao Mountain
2022, 35(1): 150-157. doi: 10.13275/j.cnki.lykxyj.2022.01.017
[Abstract](2461) [FullText HTML] (1581) [PDF 834KB](45) [Cited by] ()
Objective To examine the influence of interspecific relationship on the natural regeneration and community stability of Pinus tabuliformis plantation in Zhongtiao Mountain, and provide a theoretical basis for the management of P. tabuliformis plantation. Method Based on the survey data of the P. tabuliformis plantation community plots in Zhongtiao Mountain, the interspecific association, niche overlap and community stability of the dominant plants under the P. tabuliformis plantation were analyzed, and based on this, the role of interspecies association and niche theory in the formation of natural renewal barriers and community stability of P. tabuliformis plantations were discussed. Result The common species under the P. tabuliformis plantation in Zhongtiao Mountain are generally positively connected. The chi-square test results show that the unlinked species (372 pairs) are much higher than the linked species pairs (34 pairs), indicating that the common interspecies connections are loose. Association coefficient analysis results show that the positively connected species pairs are greater than the negatively connected species pairs, but the species pairs with significant positive association (AC≥0.20, 145 pairs) are smaller than those with significant negative association (AC≤−0.20, 168 pairs), and the most intensely competitive species with the natural regeneration of P. tabuliformis are Spiraea pubescens, Acer pictum subsp. mono, A. davidii, Clematis argentilucida, Rubia membranacea and Elymus dahurica. Pearson correlation analysis results show that the positively related species pairs are greater than the negatively related species pairs, but the significantly related species pairs are much smaller than the non-significantly related species pairs. Under the P. tabuliformis plantation, the niche of Carex lancifolia is the widest (23.47), and that of the Swida hemsleyi is the narrowest (3.87). The niche width of the natural regeneration of P. tabuliformis is 14.69, which is relatively high. The overall niche overlap of common species is low, but 11 species-pair niche overlap indexes are greater than 0.98, indicating that some species have greater ecological similarities. The niche of the natural regeneration of P. tabuliformis has the largest overlap with the niche of Sedum aizoon, Carex lancifolia, Pinus armandii and Thladiantha dubia, however, the results of the association coefficient analysis show that the natural regeneration of P. tabuliformis are positively associated with the species mentioned above, it shows that the natural regeneration of P. tabuliformis is similar to the resource utilization of these types of plants or it occupies a similar ecological space with these types of plants. The coordinate of the intersection point of the stability of the P. tabuliformis plantation community is (61.28, 38.72), which shows that the community stability is poor. Conclusion The maturity of the P. tabuliformis plantation community in Zhongtiao Mountain is relatively low, there are some species competing for the same resources, and the overall resource utilization and stability of the community is low. Competition may be one of the main reasons impeding the natural regeneration of P. tabuliformis in this area. Therefore, in the forest management activities targeting at P. tabuliformis species, more attention should be paid to removing the species that compete with the natural regeneration of P. tabuliformis under forest.
2022, 35(1): 158-165. doi: 10.13275/j.cnki.lykxyj.2022.01.018
[Abstract](2926) [FullText HTML] (1776) [PDF 1234KB](37) [Cited by] ()
Objective To simulate and predict the biomass and volume growth of natural forest using process-based model. Method Taking Larix gmelinii natural forest in Daxing’anling mountains as the research object, the application of 3-PG model was studied based on physiological process in natural forest. By adjusting the parameters of built-in module equation of the model and optimizing the fitting results of measured value and simulated value, the model parameter group suitable for deciduous forest in Northeast China was finally obtained, and the test results of different forest ages were compared. Result The model achieved good results in the simulation of DBH, stem biomass, root biomass, above ground biomass and total biomass. The coefficient of determination R2 of stem biomass and total biomass equation reached 0.98, and the relative mean error was controlled within 8%. The results of total biomass prediction and DBH prediction for different aged forest showed that the model had a good fitting effect on young, half-mature and near-mature forests. Conclusion After adjustment of the local parameters, 3-PG model can be applied to the growth prediction of natural L. gmelinii forest, and it can achieve good results in biomass prediction and DBH prediction.
2022, 35(1): 166-171. doi: 10.13275/j.cnki.lykxyj.2022.01.019
[Abstract](2926) [FullText HTML] (2312) [PDF 926KB](43) [Cited by] ()
Objective Aiming at solve the problems of complex structure and irregular shape of tree crown to realize the automatic calculation of vertical projection area of tree crown and improve the calculation accuracy of projection area of tree crown. Method A total of 453 Cunninghamia lanceolata trees were selected in the study area, and the crown width of each tree in 8 directions were accurately measured. Visual studio and ArcGIS mixed programming were used to convert the coordinates of the measured canopy radius. And the Bezier curve was used to smooth the boundary, so as to realize the automatic extraction of the vertical projection area of the tree crown, and the results were compared with that of the traditional calculation method. The "roundness" were used to evaluate the crown partial crown, and the correlation between the partial crown index and the vertical crown projection area were calculated. Result The method proposed in this paper can calculate the real canopy vertical projection area. The result indicates that the more the measurements of crown radius during calculating the canopy vertical projection area, the closer the calculation result to the real crown area. Compared with the ellipse method, the area obtained by treating the crown as a circle is closer to the real area. It is also found that, there is a significant positive correlation between the results of calculating the crown vertical projection area with different methods and the difference of the crown vertical projection area and the crown deviation index. Conclusion The area calculation method based on the shape of the canopy projection area is more accurate than the traditional area calculation method, which provides a alternative idea for the verification of forestry remote sensing crown extraction accuracy.
Screening, Identifying and Optimizing the Culture Conditions of High-efficiency Potassium-solubilizing Bacteria in the Rhizosphere of Cunninghamia lanceolata in Red Soil Area of South China
2022, 35(1): 172-181. doi: 10.13275/j.cnki.lykxyj.2022.01.020
[Abstract](2602) [FullText HTML] (1596) [PDF 1301KB](46) [Cited by] ()
Objective To screen, identify and optimize the culture conditions of high-efficiency potassium-solubilizing bacteria strains in low-potassium-stressed rhizosphere soil of Cunninghamia lanceolata plantations in red soil area of south China. Method 79 potassium-solubilizing strains were screened from the rhizosphere soil under 2-, 4-,10- and 15-years-old C. lanceolata plantations, and 20 dominant strains were selected according to their morphological and growth characteristics. The soluble potassium content and potassium-solubilizing rate of fermentation fluid were screened out for an optimal potassium-resolving strain and the genus was determined by 16S rDNA identification. The culture medium components and culture conditions of the high-efficiency potassium-solubilizing strain were optimized by single-factor experiments and orthogonal tests. Result (1) Among the 20 potassium-solubilizing bacteria strains, the potassium-releasing rate of 13 strains was positive, the potassium-solubilizing bacteria effectively decomposing potassium-feldspar accounted for 65%. (2) strain JK13, identified as Bacillus altitudinis, was identified as the best potassium-solubilizing bacterium, and its fermentation liquid soluble potassium content was 81.06 μg·mL−1, with a potassium solution rate of 60.49%, significantly higher than that of the other strains (P<0.05). (3) The results of single-factor experiment and orthogonal test showed that the strain JK13 had an initial pH of 9, a liquid loading of 30 mL·100 mL−1, an inoculation of 1%, and a culture temperature of 35℃ when the value of the liquid OD600 was significantly higher than the CK (P<0.05). Conclusion Strain JK13, which belongs to the genus B. altitudinis, shows an efficient ability to dissolve potassium, and after optimization, 0.5% mannitol and 1.5% yeast powder are the most suitable medium components, the culture conditions are weak alkali, high temperature, which can significantly improve the growth of the strains.
2022, 35(1): 182-189. doi: 10.13275/j.cnki.lykxyj.2022.01.021
[Abstract](2420) [FullText HTML] (1585) [PDF 552KB](68) [Cited by] ()
Objective To compare the differences of biomass and its distribution pattern among plantations of 4 tree species in south subtropical area, provide data for evaluating the production capacity and carbon sink potential of plantation, and provide support for the selection of tree species for improving quality and efficiency of regional plantation and building high-efficiency carbon sink forest. Method The biomass and its distribution pattern of 33-years-old Schima superba, Mytilaria laosensis, Nyssa sinensis and Cunninghamia lanceolata plantations planted in the same period on Pinus massoniana clear-cutting site in Liuzhou City, Guangxi, were studied by the method of standard plot investigation combined with biomass measurement. Result Under the same site conditions, management measures and forest age, there were significant differences in tree layer and stand biomass among different tree species plantations, the order of stand biomass was S. superba plantation (376.37 t·hm−2) > M. laosensis plantation (284.51 t·hm−2) > C. lanceolata plantation (200.02 t·hm−2) > N. sinensis plantation (175.56 t·hm−2). The biomass of tree layer accounted for 93.0%-98.3% of the stand biomass, which was in an absolute dominant position. The biomass of shrub and herb layers accounted for a relatively low proportion (0.9% in average) and had a large spatial heterogeneity but no significant difference among different plantations. The biomass proportion of humus layer (2.3% in average) was higher than that of shrub and herb layers, and the humus pool of S. superba plantation was significantly higher than that of the other three plantations. The distribution pattern of biomass in tree layer was the largest in trunk, followed by root or branch, and the lowest in leaf. The distribution pattern of biomass in shrub and herb layers was different among different plantations. Conclusion In south subtropical plantation management and stand transformation, the selection of fast-growing broad-leaved tree species for afforestation can obtain higher stand productivity and carbon sequestration benefits than coniferous forest. It is suggested to take appropriate control measures to increase understory vegetation and to increase the system stability and sustainable development potential.