2020 Vol. 33, No. 3
2020, 33(3): 0-0.
[Abstract](1478) [FullText HTML] (1135) [PDF 4048KB](79) [Cited by] ()
2020, 33(3): 1-2.
[Abstract](1467) [FullText HTML] (1080) [PDF 353KB](53) [Cited by] ()
Collection and Quality Evaluation of Elite Chestnut Germplasm Resources in Northern Yanshan Mountains
2020, 33(3): 1-11. doi: 10.13275/j.cnki.lykxyj.2020.03.001
[Abstract](4566) [FullText HTML] (2522) [PDF 1063KB](107) [Cited by] ()
Objective To select the elite germplasms with the method combining both grade and factor evaluating so as to provide references for the collection and breeding of elite chestnut germlasms. Method Sixty-three germplasms, including local varieties and elite individuals, were collected in NorthernYanshan Mountains and taking the chestnut cultivar ‘Yanshanzaofeng’ sample as the control. The ranking of quality assessments for different germplasms was determined by grade evaluating method and the factor evaluating method with the following physiological indexes: fresh weight, water content, starch, soluble sugars and soluble proteins, compared with those in ‘Yanshanzaofeng’. Result Among these germplasms, the average weight of single fresh seed was 8.7 g, while the maximum was 13.6 g and the minimum was 6.5 g. The average water content was 42.9%, while the maximum was 50.7% and the minimum was 37.6%. The average soluble sugar content was 9.8%, while the maximum was 17.1%and the minimum was 4.8%. The average starch content was 34.3%, while the maximum was 58.6% and the minimum was 17.4%. The average soluble protein content was 0.56%, while the maximum was 1.1% and the minimum was 0.16%. Conclusion There are significant differences in fresh seed weight, water content, starch, soluble sugars and soluble proteins among the seeds from different chestnut germplasms. These quality indexs could be used as indicators for the evaluation of the elite germplasms. The elite germplasms estimated through the combination of the graded scores and the factor analysis in this study will provide references for the collection and selection of the elite chestnut germplasms.
2020, 33(3): 1-1.
[Abstract](1499) [FullText HTML] (691) [PDF 164KB](5) [Cited by] ()
Characterization of Expression Patterns of Sa12F279 from Sedum alfredii under Abiotic Stress and Its Functional Interaction Analysis
2020, 33(3): 12-21. doi: 10.13275/j.cnki.lykxyj.2020.03.002
[Abstract](3490) [FullText HTML] (1587) [PDF 1201KB](68) [Cited by] ()
Objective In order to elucidate the functions of the ATP-binding cassette (ABC) protein in Sedum alfredii, a Cd hyperaccumulator, the bioinformatics analysis and expression pattern study were performed on Sa12F279 belonging to ABC protein family. Methods A local blast was carried out in the transcriptomic datasets of S. alfredii and produced a transcript categorized to ABC protein family. Further bioinformatics analysis was conducted on the phylogenetic clustering, the protein domain structures and classification of possible interaction proteins. Quantitative real-time PCR (qRT-PCR) was applied to uncover the expression patterns of Sa12F279 in the root under drought, salt, abscisic acid stresses. Result In the present work, a gene belonging to C subfamily of ABCs was identified in S. alfredii using local blast and designated as Sa12F279. The length of Sa12F279 open reading frame was 4 497 bp, coding a protein of 1 498 amino acids with pI being 6.92. The phylogenetic analysis showed that Sa12F279 was clustered with the C-subfamily of ABC protein, exhibiting uniform domain structure of TMD-NBD-TMD-NBD. Co-expression network analysis indicated that Sa12F279 served as hub genes mostly associated with metabolic process (39.8%), cellular process (29.3%), biological regulation (10.2%) and transporter activity (7.1%). The expression data from the transcriptomic datasets showed that Sa12F279 was suppressed by Cd stress in the three tissues (root, stem and leaf) at the sampling points of 24 h and 96 h. Transcriptional expression profiles responsive to drought, salt, abscisic acid (ABA) stress illustrated different response tendencies showing moderate induction. Under the treatment of ABA, the expression of Sa12F279 exhibited the tendency of decrease to elevation. Under the salt stress, Sa12F279 was up-regulated at the late stage of treatment while under the drought stress, Sa12F279 displayed the irregular tendency of elevation-decrease-elevation. Conclusion Based on the studies above, the authors characterize a gene named Sa12F279 belonging to the ABC protein family in S. alfredii and performs a comprehensive analysis including phylogenetic analysis, protein structure and co-expression network. Meanwhile, the expression profiles under different abiotic stress are also uncovered. The results could provide reference for the further studies on the ABC protein family.
2020, 33(3): 22-30. doi: 10.13275/j.cnki.lykxyj.2020.03.003
[Abstract](3460) [FullText HTML] (1482) [PDF 676KB](63) [Cited by] ()
Objective Paternity analysis of main olive cultivars progenies in Wudu Olive Orchard from Gansu province was carried out to identify the true paternal parent, explore the compatibility, and provide references for the selection of pollination cultivars in the orchard. Method 114 germplasm accessions from Wudu Olive Orchard were used as candidate paternal parents. Based on 14 pairs of fluorescence-labelled SSR markers, Cervus software was used to detect the parameters. True paternal parent identification of the four cultivars progenies (‘Chenggu 32’, ‘Arbequina’, ‘Hojiblanca’ and ‘Picual’) was performed. Result The 14 SSR loci were highly polymorphic and the cumulative exclusion probability increased with the number of loci. For the single parent known type NE-2P, the cumulative exclusion probability of the 14 loci was as high as 0.999. By comparing the genotypes of the progeny, the female parent and the candidate paternal parent, the LOD (log of likelihood ratio) values of each candidate paternal parent were calculated, and the identification of the true paternal parents of the partial progenies of the four cultivars was completed. The main paternal parent of the ‘Chenggu 32’ and ‘Picual’ progenies was ‘Arbequina’, while the main paternal parent of the ‘Arbequina’ and ‘Hojiblanca’ progenies was ‘Manzanilla’. Conclusion The SSR loci with characteristics of high polymorphism and high cumulative exclusion probability selected in the study are suitable for paternity analysis of olive cultivars progenies. The true paternal parents were identified for some of the four cultivars progenies and only ‘Chenggu 32’ among the four cultivars shows a certain self-compatibility, which provide important basis for the selection and configuration of pollination cultivars in the future orchard establishment.
2020, 33(3): 31-38. doi: 10.13275/j.cnki.lykxyj.2020.03.004
[Abstract](4509) [FullText HTML] (3350) [PDF 819KB](76) [Cited by] ()
Objective To explore the flowering biological characteristics of Pseudosasa viridula S. L. Chen et G. Y. Sheng. Method Field observation and optical anatomy were used to study the flowering biological characteristics of flowering forest facies, flowering dynamics, flower organ structure, fruiting condition and so on. Result Pseudosasa viridula is a kind of continuous flowering bamboo species, and its flowering period is from January to May of each year, and the period of full bloom is from March 1 to April 15. The types of flowering are complex and diverse, which are mainly divided into three types: old bamboo flowering type, new bamboo flowering type and non-flowering type. Under natural conditions, the fruiting rate is very low, only 0.12%, and the regeneration of post-flower bamboo forest conducts mainly through asexual reproduction. The whole inflorescence consists of 3 or 4 spikelets, with 8 - 10 florets on each spikelet. Each floret contains 1 lemma, 1 palea, 3 lodicules, stamens mostly 3 (very few are 6), 1 pistil and 3 plumose stigmas. The flowering order of the whole inflorescence is top-down, while the flowering order of florets on the same spikelet was bottom-up, so the inflorescence of Pseudosasa viridula belongs to the mixed inflorescence. The floret is monochogamy and the fruit is caryopsis. Conclusion This study provides a theoretical reference for sexual breeding and cross breeding of bamboo, as well as a certain basis for the study of low seed setting rate and cross breeding of Pseudosasa viridula.
Multifactor Relationships between Stand Structure and Soil and Water Conservation Function of Pinus tabulaeformis Plantations in the Loess Plateau of Western Shanxi
2020, 33(3): 39-47. doi: 10.13275/j.cnki.lykxyj.2020.03.005
[Abstract](3852) [FullText HTML] (2053) [PDF 895KB](79) [Cited by] ()
Objective To study quantitatively the multifactor relationships between the stand structure and soil and water conservation function of Pinus tabulaeformis plantation in the Loess Plateau of western Shanxi, so as to provide references for vegetation restoration in the Loess Plateau. Method Sixteen standard sample plots of 20 m×20 m, which were further divided into sixty-four 10 m×10 m quadrats, were established for a tree census in Caijiachuan watershed of the Loess Plateau, Shanxi Province, China. The age of these trees was about 18 years. Based on the observational and experimental data, a topography-structure-function model was built using a structural equation modeling (SEM) approach. The latent variables were the topographical factors, horizontal structure, vertical structure, soil and water conservation, and sediment reduction. Result The results indicated that the horizontal structure of the P. tabulaeformis stand was the most obvious latent variable, which was expressed in the path coefficients corresponding to soil and water conservation (pc=−0.93) and sediment reduction (pc=0.79), respectively; the stand density and tree competition index were the major drivers of the structure, with path coefficients of 0.98 and 0.97 and influence coefficients of −0.987 and −0.956. These factors were easily regulated. The sensitive functional factors that were greatly affected by structural factors were the runoff yield, sediment yield and canopy interception rate. The path coefficients were 0.97, 0.91 and 0.69, respectively and the total impact coefficients were 0.986, 0.961 and 0.731, respectively. Otherwise, the topographic factor affected soil and water conservation function through affecting the stand structure. should be kept stable within the range from 1 100 to 1 400 trees/hm2. Adjusting the stand density or tree competition index can effectively provide good benefits for soil and water conservation and sediment reduction. Multi-factor synergy can improve the vegetation quality and further promote the soil and water conservation efficiency in the ecologically significant loess area.
2020, 33(3): 48-53. doi: 10.13275/j.cnki.lykxyj.2020.03.006
[Abstract](3747) [FullText HTML] (2464) [PDF 960KB](50) [Cited by] ()
Objective To investigate the effect of resin content of pine cone scales on serotiny. Method Cone persistent ages, the degree of serotiny and the resin content of current-year cone scales in six pine species (Pinus yunnanensis Franch., P. yunnanensis var. pygmaea Hsueh., P. yunnanensis var. tenuifolia Cheng et Law., P. densata Mast., P. massoniana Lamb., and P. kesiya var. langbianensis Gaussen.) were investigated, and the correlation between resin content of cone scales and the degree of serotiny were analyzed. Result For the species whose resin content of cone scales less than 6%, the persistence of cones, which is the indication of serotiny, was not observed. In P. yunnanensis varieties characterized by serotiny, the resin content of cone scales was positively related to the degree of serotiny (R2=0.997, P=0.036). However, the relationship between the cone scale resin content and the degree of serotiny was not significant (R2=0.01, P=0.902) across these taxa, which may be due to the large genetic and environmental differences. Conclusion The results indicate that the resin content of cone scales plays an important role in pine serotiny and there will be no serotiny when it is too low. In P. yunnanensis varieties with serotiny, the serotiny degree is effected by the resin content of cone scales.
2020, 33(3): 54-62. doi: 10.13275/j.cnki.lykxyj.2020.03.007
[Abstract](4305) [FullText HTML] (2321) [PDF 957KB](90) [Cited by] ()
Objective Burning probability model was used to simulate fire burning on the landscape scale and the impacts of prescribed burning on forest flammability were assessed quantitatively. Method The data about fuel conditions of some areas of Daxing’anling after prescribed burning before the fire season of 2016 were extracted from SPOT6 satellite data. The daily weather indices in the fire season were calculated with the weather observation data near the study area by using R-software. The burning probability and fire behavior indices of the forest were simulated with BURN-P3 model for the scenarios with and without prescribed burning. Result The areas treated with prescribed burning in 2016 were 44,931 hm2, accounting for 20.8% of the total area. The average burning probability was 0.0164 and 0.0124 for the scenarios with and without prescribed burning. The average burning probability for each fuel type respectively decreased by 4.2% for deciduous coniferous forest, 3.5% for evergreen coniferous forest, 5.9% for coniferous and broad-leaved mixed forest, 2.3%for grass, and 0.6% for broad-leaved forest after prescribed burning. The average fire intensity and spread speed were 548.9 kW/m2 and 2.2 m/min under the scenario with prescribed burning. The average fire intensity and spread rate decreased by 17.9% and 24.3% due to prescribed burning. Deciduous coniferous forests and mixed forest showed high fire intensity and spread speed, and are easy to occur crown fires. The proportion of crown fire reduced by 11.7% after prescribed burning. Conclusion The prescribed burning could decrease the distribution areas of grass fuel and fuel loadings. The burn probability, fire intensity, rate of spread and crown fire fraction of the region decrease after prescribed burning. The burning probability will drop obviously in the buffer areas with 2500 m wide around the prescribed burning regions.
Genetic Transformation of AtMET1 in Populus alba × P. glandulosa ‘84K’ and Its Chemical-inducible Expression Analysis
2020, 33(3): 63-69. doi: 10.13275/j.cnki.lykxyj.2020.03.008
[Abstract](2854) [FullText HTML] (1616) [PDF 837KB](40) [Cited by] ()
Objective To study the chemically-induced expression characteristics of Arabidopsis thaliana methyltransferase gene AtMET1 in Populus alba × P. glandulosa '84K', to lay a foundation for the establishment of the poplar methylation-induced variation system and genetic improvement of poplars. Method The chemically-induced promoter and AtMET1 were transformed into genome of P. alba × P. glandulosa '84K' using Agrobacterium-mediated transformation. The hygromycin resistant plants were obtained and transgenic plants were identified as by traditional PCR and DNA sequencing. The chemical inducer 17- β -estradiol was used to induce expression of AtMET1 in leaves of in vitro leaves of a transgenic line for 0, 3, 6, 12, 24, 48, 96 and 144 h, and the expression of AtMET 1 gene was detected by Quantitative Real-time PCR (qRT-PCR). Result A total of 648 hygromycin resistant buds were obtained, among them 18 hygromycin resistant plants were screened, and all of them were identified to be transgenic plants by molecular detection method. qRT-PCR showed that the expression of AtMET1 reached its highest at 3 h by17- β -estradiol treatment, then decreased at 6 h, increased at 12 h and decreased again to less than half of the expression at 12 h. Conclusion The chemical inducer can efficiently and rapidly induce the expression of AtMET1 in transgenic poplar plant, that laid a solid foundation for the regulation mechanism of
MET1 in poplars and provided new idea and method for chemical induction of genes and genetic improvement of poplars.
2020, 33(3): 70-75. doi: 10.13275/j.cnki.lykxyj.2020.03.009
[Abstract](3066) [FullText HTML] (2132) [PDF 508KB](65) [Cited by] ()
Objective To examine the response of early growth of Betula alnoides Buch.-Ham. ex D. Don to nitrogen application and reveal the differences in the nitrogen requirement among clones. Method Four clones of Betula alnoides were used as materials in the nitrogen fertilization (urea) experiment with seven nitrogen treatments (0, 50, 150, 250, 400, 550 and 700 g urea per seedling), and the indicators such as survival rate, growth (tree height, DBH, height to crown base and crown width) and stem form (DBH/H ratio, axis persistence and stem straightness) were investigated, respectively. This study is to determine the differences in these traits among nitrogen fertilization treatments, clones and their interactions. Result The survival rate showed no obvious change, while the tree height, DBH and crown width displayed an “increase-stabilize-decrease” trend with the increase of nitrogen application amount for all the four clones in five years after planting. Moreover, the DBH/H ratio, axis persistence and stem straightness also tended to be better with the increasing nitrogen application. However the differences between nitrogen fertilizer treatments did not reach a significant level (P>0.05). There were significant differences among clones in the growth and stem form traits. The clone C3 showed the greatest performance, whose survival rate, tree height, DBH, height to crown base, crown width, axis persistence and stem straightness were 34%, 42%, 32%, 16%, 25%, 22% and 19% higher than those of clone C2, respectively. The interaction between nitrogen fertilization and clone was not significant. Conclusion Nitrogen fertilization would not affect the early afforestation growth and stem form quality of Betula alnoides. The clone C3 showed the best growth and wood quality.
The Differences of Soil Enzyme Activity and Quality Evaluation of Cunninghamia lanceolata Large-diameter Industrial Plantation under Different Understory Vegetation Management Measures
2020, 33(3): 76-84. doi: 10.13275/j.cnki.lykxyj.2020.03.010
[Abstract](3682) [FullText HTML] (3041) [PDF 664KB](61) [Cited by] ()
Objective To study the effects of different understory vegetation management measures on soil enzyme activities and quality in Cunninghamia lanceolata large-diameter industrial plantation. Method Taking Cunninghamia lanceolata large-diameter industrial plantation as the research object, This study analyzed soil enzyme activities of plantation under three kinds of understory vegetation management measures, i.e. understory vegetation protection (UP), understory vegetation removal (UR) and understory interplanting (IP). The integrated quantitative evaluation on soil quality was made by principle components analysis taking soil enzymes as soil biological activity indexes combining with soil physical and chemical characteristics. Result The IP increased the sucrase activity in the soils with the depth of 0-20 cm, and there was no obvious difference between the sucrase activity in the soils with the depths of 20-40 and 40~60 cm under these understory vegetation management measures. Compared with UR and IP, the UP showed better effect in increasing soil catalase activity and decreasing soil urease activity, and the soil urease and catalase activity under UR and IP showed no obvious difference. The ranking of soil acid phosphatase activity under the three kinds of understory vegetation management measures was IP>UR>UP, and the ranking of soil polyphenol oxidase activity was UP>IP>UR. The activities of urease, sucrase and polyphenol oxidase in soil under different understory vegetation management measures showed a big difference, and the response of polyphenol oxidase to understory vegetation management measures was more sensitive and was reflected in deeper soil layer. Except acid phosphatase activity, the activities of other soil enzyme showed a obvious property of surface-aggregation, and decreased with the deepening of soil layer. The contents of organic matter and hydrolyzed nitrogen showed extremely significant or significant positive correlation with the activities of the 5 kinds of soil enzyme, the content of available phosphorus showed extremely significant positive correlation with the activities of sucrase, urease and acid phosphatase, and the content of available potassium showed extremely significant positive correlation with the activities of sucrase, catalase and polyphenol oxidase, the activities of soil enzymes were less dependent on the soil physical properties. Soil enzyme activity was taken as one of soil quality indexes, combining with soil physical and chemical characteristics, three principal components were extracted through principal component analysis, reflecting 75.31% of the original information amount. The ranking of soil quality index among different understory vegetation management measures was IP>UP>UR. Conclusion To sum up, in the large diameter Cunninghamia lanceolata plantation, the effect of planting Phoebe bourmei under the plantation is the best to maintain and improve the soil quality, followed by protecting understory vegetation, and the effect of understory vegetation removal is poor.
2020, 33(3): 85-91. doi: 10.13275/j.cnki.lykxyj.2020.03.011
[Abstract](3141) [FullText HTML] (2263) [PDF 774KB](56) [Cited by] ()
Objective When polarimetric SAR data are used to invert tree height, time decorrelation factor is the main factor affecting inversion accuracy. Random-Motion-over-Ground (RMoG) model is one of the most effective models, but it has the disadvantages of difficult inversion and long time-consuming. Here, a simplified RMoG model is proposed. Method In this study, the ground motion was neglected, the vegetation canopy motion was retained, and the vegetation volume scattering formula was rewritten. Then, the ground phase was judged by linear fitting of multiple coherence coefficients, and the decoherence value of pure volume scattering was estimated by PD polarization coherence optimization method. Finally, the rewritten vegetation volume scattering formula was used to establish a survey. Based on the fixed extinction coefficient, the height of vegetation can be retrieved by looking-up table. To verify the validity of this method, the remote sensing data of BioSAR 2007 project were tested in Remingstorp, southern Sweden. The inversion results of the four models were compared and evaluated with the determination coefficient (R2) and the root mean square error (RMSE). Result This method can improve the overestimation problem of three-stage algorithm. In terms of accuracy comparison, the R2 of three-stage algorithm is 0.78 and RMSE is 8.52; the R2 of RMoG model is 0.47 and RMSE is 4.17; the R2 of RMoGL model is 0.48 and RMSE is 2.50; the R2 of this method is 0.53 and RMSE is 6.24. It is showed that this method is better in accuracy compared with three-stage algorithm, and can effectively reduce the inversion time compared with RMoG model and RMoGL model. Conclusion It is effective to eliminate time-related effects by adding vegetation canopy movement. Compared with three-stage algorithm, RMoG model and RMoGL model, the simplified RMoG model has the advantages of high accuracy and less time-consuming.
Mortality Model of Larix olgensis-Abies nephrolepis-Picea jazoensis Mixed Stands Based on Cox Proportional Hazard Function and Mixed Effect Model
2020, 33(3): 92-98. doi: 10.13275/j.cnki.lykxyj.2020.03.012
[Abstract](2743) [FullText HTML] (1464) [PDF 807KB](42) [Cited by] ()
Objective The survival analysis method and mixed effect model are combined to construct tree mortality model and improve the simulation precision of the model. Method Taking 20 plots of Larix olgensis-Abies nephrolepis-Picea jazoensis mixed stand in Wangqing Forestry Bureau of Jilin Province as examples, the tree mortality and survival model were constructed based on Cox proportional hazard function of survival analysis method, and the stand factor and site factor was added into the model as covariates. The plot’s random effect was considered and compared with the simulation effect of the traditional model. Result It showed that the Cox proportional hazard function model had fitting goodness in describing tree mortality. The initial DBH of tree was negatively correlated with the hazard function of the tree, and positively correlated with survival rate. The BAL was positively correlated with the hazard function of the tree, and negatively correlated with survival rate. The initial stand density per hectare was positively correlated with the hazard function of the tree, and negatively correlated with survival rate. Compared with the fixed effect model, the accuracy of Cox proportional hazard function model was greatly improved after considering plot’s random effect. Because the BAL and initial stand density per hectare showed no significant effect after considering the plot’srandom effect, only the initial DBH was considered, and the difference also reached a significant level. Conclusion In forest management, the Cox proportional hazard function model provides a good basis for determining the reasonable management density for forest operators.
Dynamic Visual Simulation of Stand Multi-objective Management Based on Simulated Annealing Algorithm
2020, 33(3): 99-106. doi: 10.13275/j.cnki.lykxyj.2020.03.013
[Abstract](3738) [FullText HTML] (2911) [PDF 1173KB](70) [Cited by] ()
Objective Based on simulated annealing algorithm, a multi-objective forest management method considering the health status of stand structure and average diameter of stand was studied. The individual tree growth equation was used to realize the dynamic visualization of the stand management based on the Unity3D visualization engine. Method Based on 2012-2017 survey data of 5 Chinese fir (Cunninghamia lanceolata) sample stands located in Huangfengqiao State-owned Forest Farm of You County, Hunan Province, considering the distribution status, competition degree and nutrient space of the stand, the spatial structure function was established by three structural parameters: average angular scale, average size ratio and forest congestion degree. On the basis of spatial structure function, taking the healthy forest structure and the average diameter as management objectives, taking the results of a combinatorial permutation of thinned trees as the set of management planning with competition index as reference, the simulated annealing algorithm was used to select the optimal thinning mangement planning. Finally, by establishing a individual trees growth equation considering the variable growth rate of Hegyi competition index, the structural analysis-management-growth method was continuously iterated and the dynamic visualization of the forest management based on Unity3D rendering engine was realized. Result The dynamic visualization of the management dynamics was carried out on the plot 5 (initial stand of 230 trees, 16-years-old, average diameter 20.21 cm) with the healthy stand structure and average diameter of 30 cm as target. The stand was simulated thinned in the 21st, 26th, and 31st years. When the forest was 31 years old (after thinning), the average diameter reached 30.10 cm, the average angular scale of the forest was 0.65, and the forest congestion was 0.74, which showed a health level. Conclusion The dynamic visual simulation method of forest multi-objective management based on simulated annealing algorithm proposed in this paper can simulate forest dynamics and meet the multi-objective management demand. The image is intuitive, and can support research and production.
Effects of Uneven-aged Cunninghamia lanceolata and Evergreen Broadleaved Mixed Plantations on Soil Aggregate Stability and Soil Organic Carbon and Nutrients Stocks
2020, 33(3): 107-115. doi: 10.13275/j.cnki.lykxyj.2020.03.014
[Abstract](3940) [FullText HTML] (2325) [PDF 1033KB](74) [Cited by] ()
Objective To study the effect of uneven-aged mixed plantations (Cunninghamia lanceolata + evergreen broadleaved tree species) on soil aggregates stability, organic carbon and nutrient storage, so as to provide references for optimizing the plantation structure and improving the sustainable forest management. Method This study investigated the uneven-aged mixed and the monoculture C. lanceolata plantations in Kaihua County of Zhejiang Province, and analyzed the stability of water-stable aggregates (WSA) and the changes of soil organic carbon (SOC), total nitrogen (TN), total phosphorus (TP) and magnesium (Mg) stocks in 0~20 cm soil layer. Result (1) The proportion of water-stable micro-aggregates (size<0.25 mm, WSA<0.25 mm) was the highest in the uneven-aged mixed and monoculture plantations. Compared with the monoculture plantation, the >5 mm aggregates proportions (WSA>5 mm), the soil mean weight diameter (MWD) and geometric mean diameter (GMD) significantly increased in the uneven-aged mixed plantations, but the soil fractal dimension (D) reduced. (2) The changes of SOC and TN stocks in different aggregate size of the uneven-aged mixed and the monoculture plantations were similar: WSA>5 mm, WSA2~5 mm>WSA0.25~2 mm>WSA<0.25 mm. The stocks of TP and Mg less varied in different aggregate sizes. (3) The stability of aggregate was mainly affected by WSA>5 mm and SOC>5 mm contents, pH, SOC2~5 m. bulk soil and soil aggregates organic carbon and nutrient stocks were mainly affected by SOCA>5 mm, 2~5 mm nitrogen contents (TNA2~5 mm) and pH. (4) Tree species composition in the uneven-aged mixed plantations greatly affected on aggregate composition and stability, SOC and nutrient stocks. The results of principal component analysis (PCA) showed that C. lanceolata+Phoebe sheareri significantly affected TP and Mg stocks in bulk soil and soil aggregates, and also affected MWD and GMD; C. lanceolata+Illicium henryi significantly affected SOC and TN stocks in bulk soil and soil aggregates. Conclusion In general, the establishment of uneven-aged C. lanceolata and broadleaved evergreen mixed plantations is beneficial to improve the soil physical and chemical properties of monoculture plantation, especially the introduced tree species of Ph. sheareri and I. henryi greatly enhance soil aggregate stability, soil organic carbon stocks and nutrient stocks of monoculture plantations.
2020, 33(3): 116-123. doi: 10.13275/j.cnki.lykxyj.2020.03.015
[Abstract](4594) [FullText HTML] (3538) [PDF 748KB](65) [Cited by] ()
Objective To analyze the aroma components and the relative contents in the flowers of two Dendrobium species, D. hancockii and D. trigonopus. Method The volatile constituents and their contents were analyzed by solid-phase microextraction (SPME) and gas chromatography-mass spectrometry (GC-MS). Result For the first time, the volatile constituents were analyzed in fresh flowers of D. trigonopus and thirty-five compounds were characterized. Fifty-two compounds were characterized in D. hancockii. The main volatile constituent in both the two species was olefin. Conclusion The characteristic aroma components are (Z)-β-Ocimene, β-Caryophyllene and Linalool in D. hancockii flower. The characteristic aroma components are (Z)-β-Ocimene, β-Caryophyllene and d-(+)-Limonene in D. trigonopus flower.
Effects of Simulated Nitrogen Deposition on the Releases of Potassium, Calcium, and Magnesium During Litter Decomposition in a Natural Evergreen Broadleaved Forest in the Rainy Area of Western China
2020, 33(3): 124-131. doi: 10.13275/j.cnki.lykxyj.2020.03.016
[Abstract](2611) [FullText HTML] (1221) [PDF 869KB](30) [Cited by] ()
Objective To study the release dynamics of potassium, calcium, and magnesium during litter decomposition under simulated nitrogen deposition, so as to better understand the nutrient cycling process of forest ecosystem under continuously increasing nitrogen depositions. Method NH4NO3 was used to establish the low level (L), medium level (M), high (H) level and the control (CK) treatments of nitrogen deposition in a natural evergreen broadleaved forest in the Rainy Area of Western China. Nylon mesh bag method was employed to simulate litter decomposition under nitrogen deposition. Experiment continued for one year and the concentration, remaining percentages and release patterns of potassium, calcium, and magnesium during litter decomposition were studied. Result After one year of decomposition, the simulated nitrogen deposition significantly inhibited the decrease of potassium in the process of litter decomposition, which significantly promoted the decrease of calcium concentration and had no significant effects on magnesium concentration. However, the simulated nitrogen deposition did not change the release pattern of potassium, calcium, and magnesium during litter decomposition. The potassium exhibited a net release pattern in all the four treatments, the calcium exhibited release-enrichment alternate pattern and the magnesium exhibited an enrichment-release pattern. The remaining percentages of potassium in L, M and H treatments increased by 3.91%, 10.27% and 13.91% respectively compared with the CK, showing that the nitrogen deposition significantly inhibited the release of potassium. The remaining percentage of calcium in L, M and H treatments decreased by 6.39%, 6.51% and 15.93% respectively compared with CK, i.e. nitrogen deposition significantly promoted the release of calcium. There was no significant difference in the remaining percentages of magnesium between the control and the nitrogen treatments i.e. simulated nitrogen deposition had no significant effect on the dynamics of magnesium during litter decomposition. Conclusion Simulated nitrogen deposition will not change the release pattern of potassium, calcium, and magnesium, but has different effects on the release rate of potassium, calcium, and magnesium during litter decomposition.
2020, 33(3): 132-138. doi: 10.13275/j.cnki.lykxyj.2020.03.017
[Abstract](3337) [FullText HTML] (2252) [PDF 745KB](65) [Cited by] ()
Objective To investigate the feasibility of LeafAnalyzer and MorphoJ software in leaf morphological chartacters of poplar, F1 progenies between Populus simonii and P. nigra were used for variation analysis and principal component analyse of leaf morphological traits. Method The leaves from 1-year-old plants of parents and progenies were collected and scanned with scanner and computer. Four leaf morphological traits (area, circumference, length and width), were measured by Digimizer software, and statistical parameters of the traits were calculated. LeafAnalyser software was used to generate spot markers of leaf shape contour through analysis of 200 mark points, build a leaf shape contour model, identify leaf shape characteristics and conduct principal component analysis (PCA). MorphoJ softeare was used to construct the profile model of leaf morphology by using Generalized Procrustes analysis (GPA), and PCA was performed to generate visual images of leaf shape changes. Result The variation coefficients from four leaf morphological traits of the hybrid progenies were all greater than 10%, and the variation coefficient of leaf area was the largest (31.74%) among four leaf traits. Based on LeafAnalyser software, principal component analysis and leaf shape variation showed that PC1 an PC2 accounted for 91.79% of the total variables, and the leaf shape profile of PC1 showed that leaf area was the factor that had the greatest influence on PC1 of leaf shape variation. According to the results of leaf shape variation an PCA with MorphoJ software showed that PC1, PC2, PC3 and PC4 accounted for 85% of the total variables. Leaf shape contour maps of four principal components were generated from the marking data, which visually showed the trend of leaf shape changes. Conclusion Based on statistical analysis of leaf characters, leaf morphological analysis software was introduced to leaf shape analysis, the genetic variation of leaf morphological traits in hybrid progenies was comprehensively and intuitively studied, and the method of leaf shape analysis software in leaf morphological research was constructed in poplar.
2020, 33(3): 139-145. doi: 10.13275/j.cnki.lykxyj.2020.03.018
[Abstract](3759) [FullText HTML] (2493) [PDF 960KB](55) [Cited by] ()
Objective To study the pH range favoring Esteya vermicola, and the effects of pine substrate on the growth of E. vermicola so as to provide references for colonization of E. vermicola in Pinus trees and the biological control against pine wood nematodes. Method E. vermicola CBS115803 (EV115803) and E. vermicola CNU120806 (EV120806) were used to test their fungal pH adaptation range. The media with different parts of pine were prepared to study the growth of E. vermicola and to observe and measure the growth rate, mycelial amount and sporulation of each strain. Result E. vermicola was adapted to the pH range of 5 to 13, and the fungi produced more aerial hyphae under acidic conditions. PDA medium added with different parts of pine trees had a certain stimulating effect for E. vermicola. When pine needles, pine bark, and pine twigs were used as the only nutrient source, E. vermicola grew better than on WA plate. E. vermicola strains grew slowly when xylem sawdust was used as a single nutrient source. Conclusion E. vermicola is adapted to the pH range of 5 to 13. It is extremely resistant to alkaline and can grow on media added with different parts of pine trees. It is expected that E. vermicola will colonize the pine trees as symbiotic fungi against invading pine wood nematodes, so that pine trees have endogenous control factors for pine wood nematodes.
2020, 33(3): 146-155. doi: 10.13275/j.cnki.lykxyj.2020.03.019
[Abstract](8026) [FullText HTML] (4320) [PDF 1135KB](52) [Cited by] ()
Objective To Understand the molecular identity and biological characteristics of wild edible fungi and lay foundation for their further culture, development and utilization. Method A wild strain of edible mushroom was examined by rDNA ITS sequence analysis and its biological characteristics were investigated by single factor and orthogonal test. Result The molecular feature of the mycelia generated from the fresh fruit body of the edible mushroom was proved to be Paxillus ammoniavirescens. The optimal carbon and nitrogen sources of its mycelial growth were found to be soluble starch and peptone with most favorable conditions of 25 ℃ and pH 4.5. Conclusion The best formula for mycelial liquid culture is 20 g soluble starch, 2 g peptone, 3.0 g KH2PO4, 4.5 g MgSO4 and 1 liter of water. In average, 80 mg dry weight of mycelia can be generated, which is obviously higher than other culture formulas.
Effects of Microhabitat Improvement on the Growth of Sabina vulgaris in the Arid and Barren Mountainous Area of Taihang Mountains
2020, 33(3): 156-163. doi: 10.13275/j.cnki.lykxyj.2020.03.020
[Abstract](2232) [FullText HTML] (1051) [PDF 823KB](35) [Cited by] ()
Objective To explore the vegetation restoration technology in the arid mountainous area of Taihang Mountains. Method On the plot with artificially simulated soil layer of 15 cm in thickness, the growth, chlorophyll content, dew point water potential and biomass allocation of Sabina vulgaris, a barren tolerant plant, were studied in combination with different microhabitat improvement measures, i.e. stone mulching (ST), plastic film mulching (DM), liquid film mulching (YM), mycorrhizal fungi treatment (JG), litterfall mulching (KL) and the control (CK). Result The increment of tree height were 385.75%, 403.03%, 1 330.00%, 1 490.00%, and 1 533.00% higher than the CK under ST, DM, YM, JG, and KL respectively. The increment of crown growth under ST, DM, JG, and KL were 185.03%, 160.36%, 239.80%, and 161.67% higher than the CK. The length of main root under ST treated in July was longer than JG, and under DM and KL in October was longer than JG. Different microhabitat improvement treatments affected the chlorophyll content in S. vulgaris leaves, and the effect of DM, KL, YM, and ST treated in June and July were significantly higher than the CK. Compared with the CK, microhabitat improvement measures would increase the dew point water potential of S. vulgaris leaves all the year round except April, and no significant difference was found in effects among various treatments. But it was observed that the effect of ST treated in July was significantly lower than DM, JG, and KL. Various treatments differed in the effect on the accumulation of aboveground and underground biomass of S. vulgaris, among which the JG had the most significant impact. The effects of various treatments on the biomass distribution of S. vulgaris varied with time. Among them, the dry weight ratio of aboveground and underground biomass under ST in October was significantly higher than under YM and KL, and the CK was significantly higher than KL. In June of next year, the dry weight ratio of aboveground and underground biomass under KL was significantly higher than CK and DM, while no significant difference was found among treatments in other months. Conclusion Microhabitat improvement measures can significantly increase the height, canopy width, leaf chlorophyll content, leaf dew point water potential, and aboveground and underground biomass of S. vulgaris in the dry and barren mountainous area of the Taihang Mountains. By comparing various microhabitat improvement measures, it is found that the effect of mycorrhizal fungi treatment is significantly better than the others. It is suggested the mycorrhizal fungi treatment should be adopted when carrying out vegetation restoration using S. vulgaris in arid mountains with a soil thickness of 15 cm in the Taihang Mountains.
2020, 33(3): 164-171. doi: 10.13275/j.cnki.lykxyj.2020.03.021
[Abstract](3421) [FullText HTML] (1609) [PDF 664KB](50) [Cited by] ()
Objective There have been many incidents in many places in China that have caused the death of mangroves by Sphaeroma terebrans. At present, there are few studies on the S. terebrans in China and there is a long research history abroad, but the research are relatively scattered. Method By researching Chinese and foreign literatures and patents, and combining with the research carried out, this paper focuses on the morphology, distribution and classification, biological characteristics, natural enemies of S. terebrans, and its damage to mangroves, the response of mangroves to S. terebrans, as well as the current prevention measures. Result The distribution range of S. terebrans is very wide, and there are geographical differences in its morphological characteristics. Genetic studies have shown that the population of S. terebrans is not a single species but a complex taxonomic group. In foreign countries, S. terebrans mainly bores holes in mangrove aerial roots, In China, they also bores holes in mangrove plant base in addition to aerial roots, and there are few reports of the former killing mangroves. The biological significance of borer holes is controversial. It can either cause ecological disaster or bring benefits to mangroves, but the former has more supporters. S. terebrans moults at least four times in a lifetime and can have three generations in two years. If the number of S. terebrans cavities on mangrove aerial roots is small, they can heal themselves. It has been documented that several marine organisms can prey on S. terebrans, but they have few kinds of natural enemies. There are some control methods for S. terebrans in China, but they are of poor operability and the problem cannot be solved fundamentally. Relevant research on prevention and control of S. terebrans still needs to be strengthened. In addition, early warning technology for S. terebrans disaster and post-disaster reconstruction technology are also imminent.
2020, 33(3): 172-183. doi: 10.13275/j.cnki.lykxyj.2020.03.022
[Abstract](8148) [FullText HTML] (6365) [PDF 831KB](330) [Cited by] ()
Objective To survey the recent developments and summarize the urgent research problems on remote sensing monitoring for pine wilt disease (PWD) induced tree mortality, then to put forward a research idea of monitoring the attacked pine trees via scheme of satellite-airborne-ground collaboration which can meet the complex terrain conditions of south China. Method The characteristics of physio-ecology and canopy spectra of affected pine trees were analyzed. The acquisition of remote sensing images, the location and counting of affected pine trees in the past decades were investigated. In addition, some research problems on remote sensing monitoring for PWD induced tree mortality were discussed, and the prospects of future studies were expected. Result Each monitoring platform of remote sensing for attacked pine trees has its own advantage. For example, high reliability for ground survey, multi-temporal for remote sensing satellite platform, high spatial resolution and flexibility for unmanned aerial vehicle (UAV) remote sensing platform. Of which, the technologies of UAV and high resolution satellite have made a great progress, as well as the interpretation algorithm of remote sensing images. Those two aspects provide a new idea to the quick monitoring of PWD induced pine trees. However, when monitoring the PWD induced tree mortality using the new technologies, there exist some problems, such as the single monitoring means, large position deviation, and low recognition precision and efficiency. Conclusion In the future, with the ever-increasing satellites platform and ever-lower cost of UAV, the quick locating of individual affected pine trees and evaluate the damage levels based on multi-source remote sensing data will become a new perspective.
Effects of Nitrogen Addition on Leaf Traits of Cunninghamia lanceolata and Phoebe chekiangensis Mixed Plantation
2020, 33(3): 184-192. doi: 10.13275/j.cnki.lykxyj.2020.03.023
[Abstract](3357) [FullText HTML] (1971) [PDF 878KB](55) [Cited by] ()
Objective To analyze the leaf traits of Chinese fir (Cunninghamia lanceolata) and nanmu (Phoebe chekiangensis) in pure and mixed plantations and to study the effect of nitrogen deposition on leaf economic characters. Method In this experiment, two nitrogen application levels were set by artificial nitrogen addition: 0 kg·ha-1yr-1N (contrast) and 30 kg·ha-1yr-1N (nitrogen addition). Every level consisted of three treatments: pure Chinese fir seedlings, pure nanmu seedlings and mixed Chinese fir and nanmu seedlings (1∶1 row mixing of Chinese fir seedlings and nanmu seedlings). During the experiment, eight indicators, including height of plants, diameter, crown width, fluorescence parameters, specific leaf mass, net photosynthetic rate, maximum net photosynthetic rate per unit mass and respiration rate of both Chinese fir seedlings and nanmu seedlings were measured. SPSS was used to analyze the significance of their differences among different treatments. Result The results showed that the respiration rate and photosynthetic capacity of pure Chinese fir seedlings were significantly higher than that of pure nanmu seedlings, and the specific leaf weight was significantly lower than that of nanmu seedlings. Mixed planting significantly increased the respiration rate of Chinese fir seedlings and the photosynthetic capacity of nanmu seedlings, but significantly reduced the specific leaf mass of Chinese fir seedlings and nanmu seedlings and the net photosynthetic rate of Chinese fir seedlings. This may be due to the mixing led to interspecific competition between the seedlings of the two species, both of which allocated more energy to competition, but the nanmu seedlings dominated in competition. Nitrogen addition significantly increased the specific leaf mass and photosynthetic capacity of pure Chinese fir seedlings, and also significantly increased the respiration rate and photosynthetic capacity of nanmu seedlings, but significantly decreased the specific leaf mass of two seedlings. In addition, in mixture, nitrogen application significantly reduced the photosynthetic capacity of Chinese fir seedlings and the respiration rate of nanmu seedlings, and the specific leaf quality of two seedlings also decreased significantly. This indicated that the addition of nitrogen changed the leaf economic characters of Chinese fir seedlings and nanmu seedlings under mixed state to some extent. In the condition of competition, the different responses of Chinese fir seedlings and nanmu seedlings to nitrogen adding may be associated with their own factors. Chinese fir is more sensitive to the environment than nanmu. The content of nitrogen addition in this experiment had relatively little effect on the growth of nanmu seedlings. It might also be related to the stronger acid resistance of nanmu seedlings and its higher photosynthetic-related enzymes content and enzymes activity. Conclusion Chinese fir seedlings are closer to the fast end of leaf economic spectrum, while nanmu seedlings were closer to the slow end, and the simple mixing will not change the relative position of the two seedlings in leaf economic spectrum. However, nitrogen addition can make Chinese fir seedlings develop towards the slow end of leaf economic spectrum, while nanmu seedlings develop towards the fast end of leaf economic spectrum.