[ Objective] The paper was to explore the population dynamics of Obolodiplosis robiniae (Haldemarm). [ Method ] The spatial distribution of mature larvae of O. robiniae and the damage regularity of its first generat...[ Objective] The paper was to explore the population dynamics of Obolodiplosis robiniae (Haldemarm). [ Method ] The spatial distribution of mature larvae of O. robiniae and the damage regularity of its first generation larvae on leaves of locust were studied in Fangshan District of Beijing City. [ Result] The spa- tial distribution of mature larvae of O. robin/ae in the forest was sigrrificanfly higher than those in forest edge and periphery of forest edge. The attack of the first generation larvae was mainly concentrated in the lower part of tree crown. [ Conclusion] The study provides theoretical basis for the effective control against O. robiniae.展开更多
The mechanism of plant response to water availability is a crucial research area in ecosystem adaptation to dry environments.Global change in precipitation patterns exacerbates drought risks in many regions,necessitat...The mechanism of plant response to water availability is a crucial research area in ecosystem adaptation to dry environments.Global change in precipitation patterns exacerbates drought risks in many regions,necessitating investigations of tree responses to drought.However,compared with seasonal drought events,how water use characteristics respond to long-term rainfall reduction remains poorly characterized.Here,we assessed the effects of multi-year rainfall exclusion treatments(in the 4th and 5th years)on sap flow,canopy conductance(G_(C)),and the response pattern to varying transpiration driving force(vapor pressure deficit(VPD))and soil moisture conditions in a black locust(Robinia pseudoacacia)plantation in the China's Loess Plateau.The experimental platform includes paired plots of a 30%throughfall exclusion treatment and a control within the plantation.The reduction of soil water content(SWC),either as temporal variations or as a result of rainfall exclusion treatment,generally lowered sap flow,G_(C),and the sensitivity to VPD.The difference in each index between plots was substantially greater than that among temporal variations in SWC within a plot.The trees in the control plot showed strong responses of G_(C)to temporal SWC changes,exhibiting an isohydric behavior.However,those subjected to long-term rainfall exclusion treatment had lower variations in G_(C)and the sensitivity across different SWC,exhibiting an anisohydric behavior under limited water conditions.Additionally,rainfall exclusion treatment decreased basal area(BA)increment but increased water use efficiency(WUE).The transition to anisohydric behavior suggests an adventurous pattern of water use strategy that has risks of hydraulic damage and shoot mortality.These findings provide insights into the different adaptation strategies within a species to diverse intensity and duration of drought conditions,which is crucial for sustainable forest management under climate change conditions.展开更多
Robinia pseudoacacia f. decaisneana is a transfiguration of Robinia pseudoacacia. For enhancing propagation coefficient of the species, the experiment of shoot tissue culture of Robinia pseudoacacia f. decaisneana was...Robinia pseudoacacia f. decaisneana is a transfiguration of Robinia pseudoacacia. For enhancing propagation coefficient of the species, the experiment of shoot tissue culture of Robinia pseudoacacia f. decaisneana was conducted in Forestry College of Shenyang Agricultural University from July 1999 to July 2001. The experiment included medium selection of explant induction survival, initial culture, subculture as well as rooting culture, and forming seedling with callus. The results showed that shoot segment in vitro survive rate is larger in spring than in autumn, and green dense callus could form plantlet. The best medium for initial culture was SH+0.5mg/L BA+0.05 mg/L NAA, with a propagation coefficient of 4.1 (per micro-cutting in a month), and for subculture it was B5+0.5 mg/L BA+0.05 mg/L NAA+ 10 mg/L Glu., with a propagation coefficient of 4.7. The best rooting medium was 1/2MS+0.5 mg/L NAA+10 mg/L Glu., with a rooting rate of 84.4%. These results provide reference data for reproduction of superior individuals of Robinia pseudoacacia f. decaisneana.展开更多
Robinia pseudoacacia stands act as a typical ecological protection forest in hilly semi-arid area of China. Two fields of surface runoff were separately set up in R. pseudoacacia stand and its clearcut area in the wes...Robinia pseudoacacia stands act as a typical ecological protection forest in hilly semi-arid area of China. Two fields of surface runoff were separately set up in R. pseudoacacia stand and its clearcut area in the western Liaoning Province (1850-12225 E, 4024-4234 N) for measuring the characteristics of runoff and sediment as well as soil moisture dynamics. Contractive analysis of the two land types showed that there existed a significant difference in volumes of runoff and sediment between the sites of R. pseudoacacia stand and its clearcut area. The runoff volume and sediment volume in clearcut area were much bigger than those in R. pseudoacacia stand, with an increase amount of 40%-177% for runoff and 180%-400% for sediment. Hydrograph of surface runoff of typical rainfall showed that the peak value of runoff in R. pseudoacacia stand was decreased by 1.0-2.5?0-3m3s-1 compared with that in its clearcut area, and the occurring time of peak value of runoff in R. pseudoacacia stand was 10-20 min later than that in its clearcut area. Harmonic analysis of soil moisture dynamics indicated that the soil moisture in R. pseudoacacia stand was 2.3 % higher than that in clearcut area, and the soil moisture both in R. pseudoacacia stand and its clearcut area could be divided into dry season and humid season and varied periodically with annual rainfall precipitation. It was concluded that R. pseudoacacia stand plays a very important role in storing water, increasing soil moisture, and reducing surface runoff and soil erosion.展开更多
On the sunny days, there were little diurnal changes in both azimuth and directional angle for either sun_ or shade_leaflet. However, there existed a significant diurnal change in midrib angle that reflected movements...On the sunny days, there were little diurnal changes in both azimuth and directional angle for either sun_ or shade_leaflet. However, there existed a significant diurnal change in midrib angle that reflected movements regarding evasion of light stress around noon hours. On the cloudy day, a very little diurnal difference was found in azimuth, directional and midrib angle. It is suggested that changing light environment is the main factor for inducing leaflet movement of Robinia pseudoacacia , and the rhythmical movement does not attribute to the leaflet movement. Leaf orientation control test showed that the photosynthetic rate ( Pn ), stomatal conductance ( g s ) and transpiration ( Tr ) of the artificial fixed_leaflets were significantly lower than that of control_leaflets. And the leaf temperature ( Tl ) of the fixed leaflets significantly exceeded that of control_leaflets, which may attribute to the significant difference of light interception between the fixed and control_leaflets. The light_dependent leaflet movement is the morphological adjustment of maintaining optimal physiological status.展开更多
This study was conducted to investigate ovule abortion of tetraploid Robinia pseudoacacia and its reasons. It was found that in the ovule development period of tetraploid R. pseudoacacia from 15 d after coronal openin...This study was conducted to investigate ovule abortion of tetraploid Robinia pseudoacacia and its reasons. It was found that in the ovule development period of tetraploid R. pseudoacacia from 15 d after coronal opening, the levels of growth-promoting endogenous hormones in abortive ovules were lower than those in normal ovules, and the level of a growth-inhibiting hormone was always higher than those in normal ovules, indicating that ovule abortion of tetraploid R. pseudoacacia might be related to abnormal endogenous phytohormones in ovules. This study laid a foundation for further study on highly sterile phenomenon of tetraploid R. pseudoacacia seeds.展开更多
The relationship between eco-hydrographic benefit of forest vegetation and climatic environmental factors is one of the focuses in the research on environmental protection and ecosystem countermeasures in Wetland. Th...The relationship between eco-hydrographic benefit of forest vegetation and climatic environmental factors is one of the focuses in the research on environmental protection and ecosystem countermeasures in Wetland. The runoff, sediment and soil moisture rate dynamics in Robinia pseudoacacia plantation and its clearcut area were investigated in the natural runoff experiment plots in Yellow River Delta Wet- land, Shandong Province, China. The correlation of height increment ofR. pseudoacacia with nine climate factors such as light, water, heat, etc. was analyzed by stepwise regression analysis. The results showed that the amounts of runoff and sediment in clearcut area of R. pseudoacacia were 53.9%-150.8% and 172.8%-387.1% higher than that in Robinia pseudoacacia plantation, respectively. The runoff peak value in R. pseudoacacia stand was obviously lower than that in clerarcut area, meantime, the occurrence of runoffpeak in R. pseudoacacia stand was 25 min later than in its clerarcut area. The soil moisture rates in R. pseudoacacia stand and its clearcut varied periodically with annual rainfall precipitation in both dry season and humid season. The annual mean soil moisture rate in R. pseudoacacia stand was 23.3%-25.6% higher than that in its clearcut area. Meanwhile, a regression model reflecting the correlation between the height increment of R. pseudoacacia and climatic factors was developed by stepwise regression procedure method. It showed that the light was the most important factor for the height increment ofR. pseudoacacia, followed by water and heat factors.展开更多
Seed germination process has closely relation with material transformation and energy exchange within the seed. Study on its thermal effect is important for understanding the mechanism and the influencing factors of t...Seed germination process has closely relation with material transformation and energy exchange within the seed. Study on its thermal effect is important for understanding the mechanism and the influencing factors of the seed germination. The thermogenetic curves of seed germination ofRobinia pseudoacacia was measured by a new-type conductive microcalorimeter made in Wuhan University. The relationship was analyzed between the germination thermogenetic regulation and seed germination physiology. The thermogentic curves were further analyzed by thermokinetic theory to obtain the dynamic parameters and the thermokinetic model on seed germination ofRobinia pseudoacacia. The relationship of the thermogenetic power (μ w) and the germination time(h) of the germination process of 20 grainsRobinia pseudocacia seeds at 25°C wasP=208.77/[0.1937+0.8063exp(?0.06563t)]展开更多
文摘[ Objective] The paper was to explore the population dynamics of Obolodiplosis robiniae (Haldemarm). [ Method ] The spatial distribution of mature larvae of O. robiniae and the damage regularity of its first generation larvae on leaves of locust were studied in Fangshan District of Beijing City. [ Result] The spa- tial distribution of mature larvae of O. robin/ae in the forest was sigrrificanfly higher than those in forest edge and periphery of forest edge. The attack of the first generation larvae was mainly concentrated in the lower part of tree crown. [ Conclusion] The study provides theoretical basis for the effective control against O. robiniae.
基金supported by the National Key R&D Program of China(No.2017YFC0504601)an open fund of the State Key Laboratory of Soil and Water Conservation and Desertification Control(No.F2010121002-202424).
文摘The mechanism of plant response to water availability is a crucial research area in ecosystem adaptation to dry environments.Global change in precipitation patterns exacerbates drought risks in many regions,necessitating investigations of tree responses to drought.However,compared with seasonal drought events,how water use characteristics respond to long-term rainfall reduction remains poorly characterized.Here,we assessed the effects of multi-year rainfall exclusion treatments(in the 4th and 5th years)on sap flow,canopy conductance(G_(C)),and the response pattern to varying transpiration driving force(vapor pressure deficit(VPD))and soil moisture conditions in a black locust(Robinia pseudoacacia)plantation in the China's Loess Plateau.The experimental platform includes paired plots of a 30%throughfall exclusion treatment and a control within the plantation.The reduction of soil water content(SWC),either as temporal variations or as a result of rainfall exclusion treatment,generally lowered sap flow,G_(C),and the sensitivity to VPD.The difference in each index between plots was substantially greater than that among temporal variations in SWC within a plot.The trees in the control plot showed strong responses of G_(C)to temporal SWC changes,exhibiting an isohydric behavior.However,those subjected to long-term rainfall exclusion treatment had lower variations in G_(C)and the sensitivity across different SWC,exhibiting an anisohydric behavior under limited water conditions.Additionally,rainfall exclusion treatment decreased basal area(BA)increment but increased water use efficiency(WUE).The transition to anisohydric behavior suggests an adventurous pattern of water use strategy that has risks of hydraulic damage and shoot mortality.These findings provide insights into the different adaptation strategies within a species to diverse intensity and duration of drought conditions,which is crucial for sustainable forest management under climate change conditions.
文摘Robinia pseudoacacia f. decaisneana is a transfiguration of Robinia pseudoacacia. For enhancing propagation coefficient of the species, the experiment of shoot tissue culture of Robinia pseudoacacia f. decaisneana was conducted in Forestry College of Shenyang Agricultural University from July 1999 to July 2001. The experiment included medium selection of explant induction survival, initial culture, subculture as well as rooting culture, and forming seedling with callus. The results showed that shoot segment in vitro survive rate is larger in spring than in autumn, and green dense callus could form plantlet. The best medium for initial culture was SH+0.5mg/L BA+0.05 mg/L NAA, with a propagation coefficient of 4.1 (per micro-cutting in a month), and for subculture it was B5+0.5 mg/L BA+0.05 mg/L NAA+ 10 mg/L Glu., with a propagation coefficient of 4.7. The best rooting medium was 1/2MS+0.5 mg/L NAA+10 mg/L Glu., with a rooting rate of 84.4%. These results provide reference data for reproduction of superior individuals of Robinia pseudoacacia f. decaisneana.
基金This paper was supported by Chinese 863 Plan Water-Saving Agriculture (2002AA2Z4321),the Key Knowledge Innovation Project (SCXZY0103) and The Tenth-five Plan of Liaoning Province (2001212001).
文摘Robinia pseudoacacia stands act as a typical ecological protection forest in hilly semi-arid area of China. Two fields of surface runoff were separately set up in R. pseudoacacia stand and its clearcut area in the western Liaoning Province (1850-12225 E, 4024-4234 N) for measuring the characteristics of runoff and sediment as well as soil moisture dynamics. Contractive analysis of the two land types showed that there existed a significant difference in volumes of runoff and sediment between the sites of R. pseudoacacia stand and its clearcut area. The runoff volume and sediment volume in clearcut area were much bigger than those in R. pseudoacacia stand, with an increase amount of 40%-177% for runoff and 180%-400% for sediment. Hydrograph of surface runoff of typical rainfall showed that the peak value of runoff in R. pseudoacacia stand was decreased by 1.0-2.5?0-3m3s-1 compared with that in its clearcut area, and the occurring time of peak value of runoff in R. pseudoacacia stand was 10-20 min later than that in its clearcut area. Harmonic analysis of soil moisture dynamics indicated that the soil moisture in R. pseudoacacia stand was 2.3 % higher than that in clearcut area, and the soil moisture both in R. pseudoacacia stand and its clearcut area could be divided into dry season and humid season and varied periodically with annual rainfall precipitation. It was concluded that R. pseudoacacia stand plays a very important role in storing water, increasing soil moisture, and reducing surface runoff and soil erosion.
文摘On the sunny days, there were little diurnal changes in both azimuth and directional angle for either sun_ or shade_leaflet. However, there existed a significant diurnal change in midrib angle that reflected movements regarding evasion of light stress around noon hours. On the cloudy day, a very little diurnal difference was found in azimuth, directional and midrib angle. It is suggested that changing light environment is the main factor for inducing leaflet movement of Robinia pseudoacacia , and the rhythmical movement does not attribute to the leaflet movement. Leaf orientation control test showed that the photosynthetic rate ( Pn ), stomatal conductance ( g s ) and transpiration ( Tr ) of the artificial fixed_leaflets were significantly lower than that of control_leaflets. And the leaf temperature ( Tl ) of the fixed leaflets significantly exceeded that of control_leaflets, which may attribute to the significant difference of light interception between the fixed and control_leaflets. The light_dependent leaflet movement is the morphological adjustment of maintaining optimal physiological status.
文摘This study was conducted to investigate ovule abortion of tetraploid Robinia pseudoacacia and its reasons. It was found that in the ovule development period of tetraploid R. pseudoacacia from 15 d after coronal opening, the levels of growth-promoting endogenous hormones in abortive ovules were lower than those in normal ovules, and the level of a growth-inhibiting hormone was always higher than those in normal ovules, indicating that ovule abortion of tetraploid R. pseudoacacia might be related to abnormal endogenous phytohormones in ovules. This study laid a foundation for further study on highly sterile phenomenon of tetraploid R. pseudoacacia seeds.
基金the National "11th Five Year" Plan of Science and technology (2006BAD26B06,2006BAD03A1205) Ecological Restore Project of Water Resources Ministry of China (2006-2008)
文摘The relationship between eco-hydrographic benefit of forest vegetation and climatic environmental factors is one of the focuses in the research on environmental protection and ecosystem countermeasures in Wetland. The runoff, sediment and soil moisture rate dynamics in Robinia pseudoacacia plantation and its clearcut area were investigated in the natural runoff experiment plots in Yellow River Delta Wet- land, Shandong Province, China. The correlation of height increment ofR. pseudoacacia with nine climate factors such as light, water, heat, etc. was analyzed by stepwise regression analysis. The results showed that the amounts of runoff and sediment in clearcut area of R. pseudoacacia were 53.9%-150.8% and 172.8%-387.1% higher than that in Robinia pseudoacacia plantation, respectively. The runoff peak value in R. pseudoacacia stand was obviously lower than that in clerarcut area, meantime, the occurrence of runoffpeak in R. pseudoacacia stand was 25 min later than in its clerarcut area. The soil moisture rates in R. pseudoacacia stand and its clearcut varied periodically with annual rainfall precipitation in both dry season and humid season. The annual mean soil moisture rate in R. pseudoacacia stand was 23.3%-25.6% higher than that in its clearcut area. Meanwhile, a regression model reflecting the correlation between the height increment of R. pseudoacacia and climatic factors was developed by stepwise regression procedure method. It showed that the light was the most important factor for the height increment ofR. pseudoacacia, followed by water and heat factors.
文摘Seed germination process has closely relation with material transformation and energy exchange within the seed. Study on its thermal effect is important for understanding the mechanism and the influencing factors of the seed germination. The thermogenetic curves of seed germination ofRobinia pseudoacacia was measured by a new-type conductive microcalorimeter made in Wuhan University. The relationship was analyzed between the germination thermogenetic regulation and seed germination physiology. The thermogentic curves were further analyzed by thermokinetic theory to obtain the dynamic parameters and the thermokinetic model on seed germination ofRobinia pseudoacacia. The relationship of the thermogenetic power (μ w) and the germination time(h) of the germination process of 20 grainsRobinia pseudocacia seeds at 25°C wasP=208.77/[0.1937+0.8063exp(?0.06563t)]