We investigated the culm form for one of the largest bamboo species, Phyllostachys pubescens Mazel ex Houz. in relation to the me- chanical constraint principles, i.e., elastic, stress and geometric similarity. The fi...We investigated the culm form for one of the largest bamboo species, Phyllostachys pubescens Mazel ex Houz. in relation to the me- chanical constraint principles, i.e., elastic, stress and geometric similarity. The fine-resolution analysis of the culm taper indicated that the culm for P. pubescens consisted of three or four segments with various forms, except for the butt swell. This implied that the taper of the whole culm for P. pubescens could be expressed by neither of these principles. The regression slope between culm height and diameter at breast height on the double logarithmic coordinates was 0.629, which was significantly different from the values predicted from these principles. In conclusion, none of these mechanical constraint principles can express the culm taper and height-diameter relationship, and there may be a need for a more complicated model to express the culm form for P. pubescens.展开更多
Ultrastructural changes in secondary wall formation of Phyllostachys pubescens Mazel fiber were investigated with transmission electron microscopy. Fiber developed initially with the elongation of cells containing...Ultrastructural changes in secondary wall formation of Phyllostachys pubescens Mazel fiber were investigated with transmission electron microscopy. Fiber developed initially with the elongation of cells containing ribosomes, mitochondria and Golgi bodies in the dense cytoplasm. During the wall thickening, the number of rough endoplasmic reticulum and Golgi bodies increased apparently. There were two kinds of Golgi vesicles, together with the ones from endoplasmic reticulum formed transport vesicles. Many microtubules were arranged parallel to the long axis of the cell adjacent to the plasmalemma. Along with the further development of fiber, polylamellate structure of the secondary wall appeared, with concurrent agglutination of chromatin in the nucleus, swelling and disintegration of organelles, while cortical microtubules were still arranged neatly against the inner side of plasmalemma. Lomasomes could be observed between the wall and plasmalemma. The results indicated that the organelles, such as Golgi bodies together with small vesicles, rough endoplasmic reticulum and lomasomes, played the key role in the thickening and lignification of the secondary wall of bamboo fiber, though cortical microtubules were correlative with the process as well.展开更多
The height growth of bamboo in 2008 and 2009 as well as the water contents of bamboo stump,leaves,straw,and rhizome in 2009 were measured at the Tianmu Mountain Nature Reserve.The results revealed that the relationshi...The height growth of bamboo in 2008 and 2009 as well as the water contents of bamboo stump,leaves,straw,and rhizome in 2009 were measured at the Tianmu Mountain Nature Reserve.The results revealed that the relationship between the height growth（Pn）and growth time（t）showed S-shaped curve in the two years;the water contents of bamboo stump,leaf,straw,rhizome and bamboo shoot were 0.50-2.31,0.46-1.8,0.50-1.38,0.56-1.58 and 0.89-8.96,respectively.Among them,the water content of bamboo shoot was the highest and noticeable changed,followed by bamboo stump,leaves,rhizome and straw in order.The water contents of the underground and aboveground parts respectively were 0.34-0.62 and 0.33-0.57.展开更多
Due to its rapid growth and high rate of spread, Phyllostachys pubescens can suppress other species, eventually leading to pure P. pubescens forests. Research on the patterns of litter decomposition and nutrient relea...Due to its rapid growth and high rate of spread, Phyllostachys pubescens can suppress other species, eventually leading to pure P. pubescens forests. Research on the patterns of litter decomposition and nutrient release from P. pubescens across stand mixtures are helpful to understand the decomposition and nutrient dynamics during the invasion process. However, little is known for unmanaged conditions at high elevations. Therefore, we studied the decomposition of four litter compositions comprised of different combinations of P. pubescens and Cunninghamia lanceolata foliage for one year to explore the pattern of litter decomposition and nutrient release at the Daiyun Mountain National Nature Reserve. The results show that:(1) the litter decomposed faster with a higher proportion of P. pubescens based on Olson's decay model;(2) the remaining litter compositions followed a trigonometric function model better than Olson'sdecay model and fluctuated periodically in tandem with changing temperature and precipitation;(3) the litter mixture decompositions did not support the biomass-ratio hypothesis test; and(4) there were significant binomial, power and exponential relationships between initial concentration and final amounts remaining after 1 year decomposition for C, N and P. The correlations between litter decomposition and nutrient releases were significant. The results may be used to explain the rapid spread of P. pubescens and to guide the natural management of plantations.展开更多
Plantation under the forest is a good way of agroforestry,but the canopy closure has a great influence on understory herbs’growth.In the study,different canopy closures of Phyllostachys pubescens forests were set up ...Plantation under the forest is a good way of agroforestry,but the canopy closure has a great influence on understory herbs’growth.In the study,different canopy closures of Phyllostachys pubescens forests were set up to explore its influence on the growth of Ilex latifolia Thunb.The photosynthetic characteristics of Ilex latifolia leaves under different canopy closures were determined by Li-6400 portable photosynthetic system.The results showed that the net photosynthetic rate curve of Ilex latifolia leaves of T1(canopy closure of 0.56)was bimodal with an obvious"midday depression"phenomenon,while the net photosynthetic rate curves of T2(canopy closure of 0.72)and T3(canopy closure of 0.86)were unimodal.The results of light response curve showed that the photosynthetically active radiation and transpiration rate reduced with the increasing of canopy closures.The photosynthetically active radiation,transpiration rate,stomatal conductance,and net photosynthetic rate of Ilex latifolia leaves of T2 were higher than those of T3.Although the net photosynthetic rate of T2 was lower than that of T1,it had no obvious photo-inhibition which affected plant growth.Overall,the canopy closure of 0.72 was more suitable for the growth of Ilex latifolia.The herb plantation in the bamboo forest should be considered with the canopy closure for a better growth.展开更多
We propose a novel Madake (Phyllostachys bambusoides) bamboo suspension culture model for investigation of key enzyme(s) activity involved in growth/differentiation. Sedimented Cell Volume (SCV) and fresh weight (FW) ...We propose a novel Madake (Phyllostachys bambusoides) bamboo suspension culture model for investigation of key enzyme(s) activity involved in growth/differentiation. Sedimented Cell Volume (SCV) and fresh weight (FW) of the suspension cultured cells reached 34% (v/v) and 8.7 g in 10 μM 2,4-dichlorophenoxyacetic acid (2,4-D)-containing medium while only 7% (v/v) SCV and 1.9 g FW of the cells in 10 μM gibberellic acid (GA3)-containing medium in 14 days. Proportion of mitotically active cells (S to G2/M phases) at a log phase was identified as 29.5% in the former cells with tiny cytoplasmic features while 5.4% in the latter cells with elongation, wall thickening, and lignification by using flow cytometry and laser scanning microscopic analysis. The total β-glucosidase (BGL) activity under the 2,4-D condition increased from 4.8 U in day 2 to 26.2 U in day 14 (ca. 5.5-fold) while a slight reduction, from 4.4 U in day 2 to 2.1 U in day 14 (ca. 0.5-fold), occurred when cell division was suppressed under the GA3 condition. Ratio of the BGL activity of the soluble fractions to the membrane-associated fractions varied depending of the culture condition. The ratio was stable (2 to 8) during the culture period under the 2,4-D condition. Interestingly, the activity of the soluble enzyme fractions increased up to ca. 65% under the GA3 condition in inverse proportion to the membrane-associated enzymes. All together, it was strongly suggested that the detected specificity/variability of BGL activity is potentially involved in cell division and lignification in Madake bamboo cells.展开更多
The ionic liquid (IL)-water mixture pretreated bamboo (Phyllostachys edulis) samples were applied in the research of thermal decomposition. [BMIM]Cl (1-Butyl-3-methylimidazolium chloride)- water and [BMIM]BF4 (1-Butyl...The ionic liquid (IL)-water mixture pretreated bamboo (Phyllostachys edulis) samples were applied in the research of thermal decomposition. [BMIM]Cl (1-Butyl-3-methylimidazolium chloride)- water and [BMIM]BF4 (1-Butyl-3-methylimidazolium tetrafluoroborate)-water were used in pretreatment process. Compositions of the untreated bamboo and pretreated bamboo were compared. The results of X-ray diffraction analysis (XRD) were analyzed to explain the effect of ILs mixture on cellulose crystalline structure. The pretreated cellulose with [BMIM]Cl- water mixture was tend to produce the more gaseous products, which were associated with the decomposition rate. The behavior of more CO and CH4 gaseous products and less tar in the thermal decomposition products could be attributed to ILs-water mixture pretreatment process. The potential and some problems of ILs-water mixture pretreatment method applied in thermal chemical conversion methods were also discussed.展开更多
Soil samples for conventional management (CM) and intensive management (IM) practices were taken over a year at 2-month intervals to determine the effect of management practices on soil organic carbon (SOC) and to qua...Soil samples for conventional management (CM) and intensive management (IM) practices were taken over a year at 2-month intervals to determine the effect of management practices on soil organic carbon (SOC) and to quantify seasonal dynamics in SOC for bamboo (Phyllostachys pubescens Mazel ex H. de Lehaie) stands. The results with IM compared to CM showed large decreases in total organic carbon (TOC), microbial biomass carbon (MBC), water-soluble organic carbon (WSOC), and the MBC/TOC ratio in the soils. With all IM plots in the 0-20 cm depth across sampling periods, average decreases compared with CM were: TOC, 12.1%; MBC, 26.1%; WSOC, 29.3%; the MBC/TOC ratio, 16.1%; and the WSOC/TOC ratio, 20.0%. Due to seasonal changes of climate, seasonal variations were observed in MBC and WSOC. Soil MBC in the 0-20 cm depth in September compared to May were 122.9% greater for CM and 57.6% greater for IM. However, due primarily to soil temperature, soil MBC was higher during the July to November period, whereas because of soil moisture, WSOC was lower in July and January. This study revealed that intensive management in bamboo plantations depleted the soil C pool; therefore, soil quality with IM should be improved through application of organic manures.展开更多
Biomineralization of Si by plants into phytolith formation and precipitation of Si into clays during weathering are two important processes of silicon’s biogeochemical cycle. As a silicon-accumulating plant, the wide...Biomineralization of Si by plants into phytolith formation and precipitation of Si into clays during weathering are two important processes of silicon’s biogeochemical cycle. As a silicon-accumulating plant, the widely distributed and woody Phyl-lostachys heterocycla var. pubescens (moso bamboo) contributes to storing silicon by biomineralization and, thus, prevents eu-trophication of nearby waterbodies through silicon’s erosion of soil particles. A study on the organic pool and biological cycle of silicon (Si) of the moso bamboo community was conducted in Wuyishan Biosphere Reserve, China. The results showed that: (1) the standing crop of the moso bamboo community was 13355.4 g/m2, of which 53.61%, 45.82% and 0.56% are represented by the aboveground and belowground parts of moso bamboos, and the under-story plants, respectively; (2) the annual net primary production of the community was 2887.1 g/(m2·a), among which the aboveground part, belowground part, litterfalls, and other fractions, accounted for 55.86%, 35.30%, 4.50% and 4.34%, respec-tively; (3) silicon concentration in stem, branch, leaf, base of stem, root, whip of bamboos, and other plants was 0.15%, 0.79%, 3.10%, 4.40%, 7.32%, 1.52% and 1.01%, respectively; (4) the total Si accumulated in the standing crop of moso bamboo com-munity was 448.91 g/m2, with 99.83% of Si of the total community stored in moso bamboo populations; (5) within moso bamboo community, the annual uptake, retention, and return of Si were 95.75, 68.43, 27.32 g/(m2·a), respectively; (6) the turnover time of Si, which is the time an average atom of Si remains in the soil before it is recycled into the trees or shrubs, was 16.4 years; (7) the enrichment ratio of Si in the moso bamboo community, which is the ratio of the mean concentration of nutrients in the net primary production to the mean concentration of nutrients in the biomass of a community, was 0.64; and lastly, (8) moso bamboo plants stored about 1.26×1010 kg of silicon in the organic pool made up by the moso bamboo forests in the subtropical area of China.展开更多
Objective To identify the bamboo VOCs (volatile organic compounds) effect on animal physiological indices, which associated with human health. Methods GC/MS was used to analyze the volatile organic compounds from Mos...Objective To identify the bamboo VOCs (volatile organic compounds) effect on animal physiological indices, which associated with human health. Methods GC/MS was used to analyze the volatile organic compounds from Moso bamboo (Phyllostachys heterocyla cv. pubescens). The effect of VOCs on environmental health was evaluated by analyzing the metabolic indices of the type 2 diabetic mouse model. Results Spectra of VOC generated by GC/MS were blasted against an in-house MS library confirming the identification of 33 major components that were manually validated. The relative constituent compounds as a percentage of total VOCs determined were alcohols (34.63%), followed by ether (22.02%), aldehyde (15.84%), ketone (11.47%), ester (4.98%), terpenoid (4.38%), and acids (3.83%). Further experimentation established that the metabolic incidence of the disease can be improved if treated with vanillin, leaf alcohol,β-ionone and methyl salicylate. The effects of these VOCs on type 2 diabetes were evident in the blood lipid and blood glucose levels. Conclusion Our model suggests that VOCs can potentially control the metabolic indices in type 2 diabetes mice. This experiment data also provides the scientific basis for the comprehensive utilization of ornamental bamboos and some reference for other similar study of environmental plants.展开更多
Winter bamboo shoots are widely used in Asian cuisine. We surveyed growth depth （tail depth and root depth）, harvest speed, and harvest processes to provide information for developing new harvest technology. The tai...Winter bamboo shoots are widely used in Asian cuisine. We surveyed growth depth （tail depth and root depth）, harvest speed, and harvest processes to provide information for developing new harvest technology. The tail depth of most winter bamboo shoots was 100 350 mm below the soil surface, and the root depth was 200 500 mm below the soil surface. Most winter bamboo shoots were difficult to locate with only the naked eye. The digging depth was 200 500 mm to cut winter bamboo shoots from the root. The highest harvest rate was 7.75 times faster than the slowest one and the average harvest speed ratio of men： women was about 1.71：1. The harvest process of winter bamboo shoots was divisible into three steps： searching, digging a hole （around the shoot） and cutting the root. The ratio of searching time to the sum of digging and cutting time was about 8：1, showing that searching required more time than digging and cutting together.展开更多
Understanding the relationship between tree height （H） and diameter at breast height （D） is vital to forest design, monitoring and biomass estimation. We developed an allometric equation model and tested its appli...Understanding the relationship between tree height （H） and diameter at breast height （D） is vital to forest design, monitoring and biomass estimation. We developed an allometric equation model and tested its applicability for unevenly aged stands of moso bamboo forest at a regional scale. Field data were collected for 21 plots. Based on these data, we identified two strong power relationships： a corre- lation between the mean bamboo height （Hm） and the upper mean H （Hu）, and a correlation between the mean D （Din） and the upper mean D （Du）. Simulation results derived from the aUometric equation model were in good agreement with observed culms derived from the field data for the 21 stands, with a root-mean-square error and relative root-mean-square error of 1.40 m and 13.41%, respectively. These results demonstrate that the allometric equation model had a strong predictive power in the unevenly aged stands at a regional scale. In addition, the estimated average height-diameter （H-D） model for South Anhui Province was used to predict H for the same type of bamboo in Hunan Province based on the measured D, and the results were highly similar. The allometric equation model has multiple uses at the regional scale, including the evaluation of the variation in the H- D relationship among regions. The model describes the average H-D relationship without considering the effects caused by variation in site conditions, tree density and other factors.展开更多
Bamboo shoots grow quickly through the rapid elongation of intemodes. In order to veri~ whether DNA methylation affects bamboo shoot elongation, we compared DNA methylation levels at five develop- mental stages of bam...Bamboo shoots grow quickly through the rapid elongation of intemodes. In order to veri~ whether DNA methylation affects bamboo shoot elongation, we compared DNA methylation levels at five develop- mental stages of bamboo （Phyllostachys praecox）, including young bamboo shoot of 40-cm at length （S1）, bamboo shoot of 2-cm at length （S2）, young leaf （Y1）, leaf （Y2）, and aging leaf （M）, by using amplified fragment length polymorphism （AFLP） based on KpnI/MseI and Acc65I/MseI platforms. The polymorphism ratio of methylated to un- methylated DNA sites in bamboo shoot （$1 and $2） was higher than that in leaf （Y1, Y2 and M）. The polymorphism ratio of methylated to un- methylated DNA sites in $2 was highest （32%）. Our results suggest that DNA methylation changed greatly at bamboo growing stages, especially in stage of rapid elongation of intemodes.展开更多
基金supported in part by the Sumitomo Foundation (Grant no. 083062)
文摘We investigated the culm form for one of the largest bamboo species, Phyllostachys pubescens Mazel ex Houz. in relation to the me- chanical constraint principles, i.e., elastic, stress and geometric similarity. The fine-resolution analysis of the culm taper indicated that the culm for P. pubescens consisted of three or four segments with various forms, except for the butt swell. This implied that the taper of the whole culm for P. pubescens could be expressed by neither of these principles. The regression slope between culm height and diameter at breast height on the double logarithmic coordinates was 0.629, which was significantly different from the values predicted from these principles. In conclusion, none of these mechanical constraint principles can express the culm taper and height-diameter relationship, and there may be a need for a more complicated model to express the culm form for P. pubescens.
文摘Ultrastructural changes in secondary wall formation of Phyllostachys pubescens Mazel fiber were investigated with transmission electron microscopy. Fiber developed initially with the elongation of cells containing ribosomes, mitochondria and Golgi bodies in the dense cytoplasm. During the wall thickening, the number of rough endoplasmic reticulum and Golgi bodies increased apparently. There were two kinds of Golgi vesicles, together with the ones from endoplasmic reticulum formed transport vesicles. Many microtubules were arranged parallel to the long axis of the cell adjacent to the plasmalemma. Along with the further development of fiber, polylamellate structure of the secondary wall appeared, with concurrent agglutination of chromatin in the nucleus, swelling and disintegration of organelles, while cortical microtubules were still arranged neatly against the inner side of plasmalemma. Lomasomes could be observed between the wall and plasmalemma. The results indicated that the organelles, such as Golgi bodies together with small vesicles, rough endoplasmic reticulum and lomasomes, played the key role in the thickening and lignification of the secondary wall of bamboo fiber, though cortical microtubules were correlative with the process as well.
基金Supported by Science and Technology Department 973 Program(2005CB422207,2002CB111504,2002CB410811,2005CB422208)Science and Technology Department Data Share Platform Construction Program(2006DKA32300-08)+2 种基金Science Department National Cooperation Program(200073819)National Natural Science Fund Program(40671132)Scientific Fundamental Work Special Program(2007FY110300-8)~~
文摘The height growth of bamboo in 2008 and 2009 as well as the water contents of bamboo stump,leaves,straw,and rhizome in 2009 were measured at the Tianmu Mountain Nature Reserve.The results revealed that the relationship between the height growth（Pn）and growth time（t）showed S-shaped curve in the two years;the water contents of bamboo stump,leaf,straw,rhizome and bamboo shoot were 0.50-2.31,0.46-1.8,0.50-1.38,0.56-1.58 and 0.89-8.96,respectively.Among them,the water content of bamboo shoot was the highest and noticeable changed,followed by bamboo stump,leaves,rhizome and straw in order.The water contents of the underground and aboveground parts respectively were 0.34-0.62 and 0.33-0.57.
基金funded by the Fujian Provincial Education Department (Grants No. JA15154)Youth Foundation of Fujian Agriculture and Forestry University (Grants No. 2010007)
文摘Due to its rapid growth and high rate of spread, Phyllostachys pubescens can suppress other species, eventually leading to pure P. pubescens forests. Research on the patterns of litter decomposition and nutrient release from P. pubescens across stand mixtures are helpful to understand the decomposition and nutrient dynamics during the invasion process. However, little is known for unmanaged conditions at high elevations. Therefore, we studied the decomposition of four litter compositions comprised of different combinations of P. pubescens and Cunninghamia lanceolata foliage for one year to explore the pattern of litter decomposition and nutrient release at the Daiyun Mountain National Nature Reserve. The results show that:(1) the litter decomposed faster with a higher proportion of P. pubescens based on Olson's decay model;(2) the remaining litter compositions followed a trigonometric function model better than Olson'sdecay model and fluctuated periodically in tandem with changing temperature and precipitation;(3) the litter mixture decompositions did not support the biomass-ratio hypothesis test; and(4) there were significant binomial, power and exponential relationships between initial concentration and final amounts remaining after 1 year decomposition for C, N and P. The correlations between litter decomposition and nutrient releases were significant. The results may be used to explain the rapid spread of P. pubescens and to guide the natural management of plantations.
文摘Plantation under the forest is a good way of agroforestry,but the canopy closure has a great influence on understory herbs’growth.In the study,different canopy closures of Phyllostachys pubescens forests were set up to explore its influence on the growth of Ilex latifolia Thunb.The photosynthetic characteristics of Ilex latifolia leaves under different canopy closures were determined by Li-6400 portable photosynthetic system.The results showed that the net photosynthetic rate curve of Ilex latifolia leaves of T1(canopy closure of 0.56)was bimodal with an obvious"midday depression"phenomenon,while the net photosynthetic rate curves of T2(canopy closure of 0.72)and T3(canopy closure of 0.86)were unimodal.The results of light response curve showed that the photosynthetically active radiation and transpiration rate reduced with the increasing of canopy closures.The photosynthetically active radiation,transpiration rate,stomatal conductance,and net photosynthetic rate of Ilex latifolia leaves of T2 were higher than those of T3.Although the net photosynthetic rate of T2 was lower than that of T1,it had no obvious photo-inhibition which affected plant growth.Overall,the canopy closure of 0.72 was more suitable for the growth of Ilex latifolia.The herb plantation in the bamboo forest should be considered with the canopy closure for a better growth.
文摘We propose a novel Madake (Phyllostachys bambusoides) bamboo suspension culture model for investigation of key enzyme(s) activity involved in growth/differentiation. Sedimented Cell Volume (SCV) and fresh weight (FW) of the suspension cultured cells reached 34% (v/v) and 8.7 g in 10 μM 2,4-dichlorophenoxyacetic acid (2,4-D)-containing medium while only 7% (v/v) SCV and 1.9 g FW of the cells in 10 μM gibberellic acid (GA3)-containing medium in 14 days. Proportion of mitotically active cells (S to G2/M phases) at a log phase was identified as 29.5% in the former cells with tiny cytoplasmic features while 5.4% in the latter cells with elongation, wall thickening, and lignification by using flow cytometry and laser scanning microscopic analysis. The total β-glucosidase (BGL) activity under the 2,4-D condition increased from 4.8 U in day 2 to 26.2 U in day 14 (ca. 5.5-fold) while a slight reduction, from 4.4 U in day 2 to 2.1 U in day 14 (ca. 0.5-fold), occurred when cell division was suppressed under the GA3 condition. Ratio of the BGL activity of the soluble fractions to the membrane-associated fractions varied depending of the culture condition. The ratio was stable (2 to 8) during the culture period under the 2,4-D condition. Interestingly, the activity of the soluble enzyme fractions increased up to ca. 65% under the GA3 condition in inverse proportion to the membrane-associated enzymes. All together, it was strongly suggested that the detected specificity/variability of BGL activity is potentially involved in cell division and lignification in Madake bamboo cells.
文摘The ionic liquid (IL)-water mixture pretreated bamboo (Phyllostachys edulis) samples were applied in the research of thermal decomposition. [BMIM]Cl (1-Butyl-3-methylimidazolium chloride)- water and [BMIM]BF4 (1-Butyl-3-methylimidazolium tetrafluoroborate)-water were used in pretreatment process. Compositions of the untreated bamboo and pretreated bamboo were compared. The results of X-ray diffraction analysis (XRD) were analyzed to explain the effect of ILs mixture on cellulose crystalline structure. The pretreated cellulose with [BMIM]Cl- water mixture was tend to produce the more gaseous products, which were associated with the decomposition rate. The behavior of more CO and CH4 gaseous products and less tar in the thermal decomposition products could be attributed to ILs-water mixture pretreatment process. The potential and some problems of ILs-water mixture pretreatment method applied in thermal chemical conversion methods were also discussed.
基金Project supported by the National Natural Science Foundation of China (No. 30271072) and the Zhejiang Provincial Natural Science Foundation of China (No. 301250).
文摘Soil samples for conventional management (CM) and intensive management (IM) practices were taken over a year at 2-month intervals to determine the effect of management practices on soil organic carbon (SOC) and to quantify seasonal dynamics in SOC for bamboo (Phyllostachys pubescens Mazel ex H. de Lehaie) stands. The results with IM compared to CM showed large decreases in total organic carbon (TOC), microbial biomass carbon (MBC), water-soluble organic carbon (WSOC), and the MBC/TOC ratio in the soils. With all IM plots in the 0-20 cm depth across sampling periods, average decreases compared with CM were: TOC, 12.1%; MBC, 26.1%; WSOC, 29.3%; the MBC/TOC ratio, 16.1%; and the WSOC/TOC ratio, 20.0%. Due to seasonal changes of climate, seasonal variations were observed in MBC and WSOC. Soil MBC in the 0-20 cm depth in September compared to May were 122.9% greater for CM and 57.6% greater for IM. However, due primarily to soil temperature, soil MBC was higher during the July to November period, whereas because of soil moisture, WSOC was lower in July and January. This study revealed that intensive management in bamboo plantations depleted the soil C pool; therefore, soil quality with IM should be improved through application of organic manures.
基金Project (No. 30370275) supported by the National Natural Science Foundation of China
文摘Biomineralization of Si by plants into phytolith formation and precipitation of Si into clays during weathering are two important processes of silicon’s biogeochemical cycle. As a silicon-accumulating plant, the widely distributed and woody Phyl-lostachys heterocycla var. pubescens (moso bamboo) contributes to storing silicon by biomineralization and, thus, prevents eu-trophication of nearby waterbodies through silicon’s erosion of soil particles. A study on the organic pool and biological cycle of silicon (Si) of the moso bamboo community was conducted in Wuyishan Biosphere Reserve, China. The results showed that: (1) the standing crop of the moso bamboo community was 13355.4 g/m2, of which 53.61%, 45.82% and 0.56% are represented by the aboveground and belowground parts of moso bamboos, and the under-story plants, respectively; (2) the annual net primary production of the community was 2887.1 g/(m2·a), among which the aboveground part, belowground part, litterfalls, and other fractions, accounted for 55.86%, 35.30%, 4.50% and 4.34%, respec-tively; (3) silicon concentration in stem, branch, leaf, base of stem, root, whip of bamboos, and other plants was 0.15%, 0.79%, 3.10%, 4.40%, 7.32%, 1.52% and 1.01%, respectively; (4) the total Si accumulated in the standing crop of moso bamboo com-munity was 448.91 g/m2, with 99.83% of Si of the total community stored in moso bamboo populations; (5) within moso bamboo community, the annual uptake, retention, and return of Si were 95.75, 68.43, 27.32 g/(m2·a), respectively; (6) the turnover time of Si, which is the time an average atom of Si remains in the soil before it is recycled into the trees or shrubs, was 16.4 years; (7) the enrichment ratio of Si in the moso bamboo community, which is the ratio of the mean concentration of nutrients in the net primary production to the mean concentration of nutrients in the biomass of a community, was 0.64; and lastly, (8) moso bamboo plants stored about 1.26×1010 kg of silicon in the organic pool made up by the moso bamboo forests in the subtropical area of China.
基金supported by the National Natural Science Foundation of China(41271337)the Zhejiang Provincial Natural Science Foundation(LY14E030016)
文摘Objective To identify the bamboo VOCs (volatile organic compounds) effect on animal physiological indices, which associated with human health. Methods GC/MS was used to analyze the volatile organic compounds from Moso bamboo (Phyllostachys heterocyla cv. pubescens). The effect of VOCs on environmental health was evaluated by analyzing the metabolic indices of the type 2 diabetic mouse model. Results Spectra of VOC generated by GC/MS were blasted against an in-house MS library confirming the identification of 33 major components that were manually validated. The relative constituent compounds as a percentage of total VOCs determined were alcohols (34.63%), followed by ether (22.02%), aldehyde (15.84%), ketone (11.47%), ester (4.98%), terpenoid (4.38%), and acids (3.83%). Further experimentation established that the metabolic incidence of the disease can be improved if treated with vanillin, leaf alcohol,β-ionone and methyl salicylate. The effects of these VOCs on type 2 diabetes were evident in the blood lipid and blood glucose levels. Conclusion Our model suggests that VOCs can potentially control the metabolic indices in type 2 diabetes mice. This experiment data also provides the scientific basis for the comprehensive utilization of ornamental bamboos and some reference for other similar study of environmental plants.
基金support by National Science Project of China with Research Grant 30900870 and 50775079Science Project of Guangdong Province with Research Grant 07300720
文摘Winter bamboo shoots are widely used in Asian cuisine. We surveyed growth depth （tail depth and root depth）, harvest speed, and harvest processes to provide information for developing new harvest technology. The tail depth of most winter bamboo shoots was 100 350 mm below the soil surface, and the root depth was 200 500 mm below the soil surface. Most winter bamboo shoots were difficult to locate with only the naked eye. The digging depth was 200 500 mm to cut winter bamboo shoots from the root. The highest harvest rate was 7.75 times faster than the slowest one and the average harvest speed ratio of men： women was about 1.71：1. The harvest process of winter bamboo shoots was divisible into three steps： searching, digging a hole （around the shoot） and cutting the root. The ratio of searching time to the sum of digging and cutting time was about 8：1, showing that searching required more time than digging and cutting together.
基金financially supported by the Special Fund for Basic Scientific Research of International Centre for Bamboo and Rattan(1632014003)National Natural Science Foundation of China(31101148 and 31300177)
文摘Understanding the relationship between tree height （H） and diameter at breast height （D） is vital to forest design, monitoring and biomass estimation. We developed an allometric equation model and tested its applicability for unevenly aged stands of moso bamboo forest at a regional scale. Field data were collected for 21 plots. Based on these data, we identified two strong power relationships： a corre- lation between the mean bamboo height （Hm） and the upper mean H （Hu）, and a correlation between the mean D （Din） and the upper mean D （Du）. Simulation results derived from the aUometric equation model were in good agreement with observed culms derived from the field data for the 21 stands, with a root-mean-square error and relative root-mean-square error of 1.40 m and 13.41%, respectively. These results demonstrate that the allometric equation model had a strong predictive power in the unevenly aged stands at a regional scale. In addition, the estimated average height-diameter （H-D） model for South Anhui Province was used to predict H for the same type of bamboo in Hunan Province based on the measured D, and the results were highly similar. The allometric equation model has multiple uses at the regional scale, including the evaluation of the variation in the H- D relationship among regions. The model describes the average H-D relationship without considering the effects caused by variation in site conditions, tree density and other factors.
基金funded by the Natural Science Foundation of China (30800879)
文摘Bamboo shoots grow quickly through the rapid elongation of intemodes. In order to veri~ whether DNA methylation affects bamboo shoot elongation, we compared DNA methylation levels at five develop- mental stages of bamboo （Phyllostachys praecox）, including young bamboo shoot of 40-cm at length （S1）, bamboo shoot of 2-cm at length （S2）, young leaf （Y1）, leaf （Y2）, and aging leaf （M）, by using amplified fragment length polymorphism （AFLP） based on KpnI/MseI and Acc65I/MseI platforms. The polymorphism ratio of methylated to un- methylated DNA sites in bamboo shoot （$1 and $2） was higher than that in leaf （Y1, Y2 and M）. The polymorphism ratio of methylated to un- methylated DNA sites in $2 was highest （32%）. Our results suggest that DNA methylation changed greatly at bamboo growing stages, especially in stage of rapid elongation of intemodes.
