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“绿量”到“绿质”:广州市空港经济区绿化景观规划探索 被引量:3
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作者 范京 胡峰 +1 位作者 姚睿 林晨薇 《规划师》 北大核心 2020年第9期57-63,共7页
文章通过对当前基于"绿量"管控的绿化景观规划进行总结与反思,指出城市重点片区的绿化景观规划应改变"绿量"导向的编制思路,转向以塑造高品"绿质"为目标,以绿化功能和属性管控为重点。同时,结合广州市空... 文章通过对当前基于"绿量"管控的绿化景观规划进行总结与反思,指出城市重点片区的绿化景观规划应改变"绿量"导向的编制思路,转向以塑造高品"绿质"为目标,以绿化功能和属性管控为重点。同时,结合广州市空港经济区绿化景观规划实践,从理念、技术和成果三方面切入,探索更多元的绿化景观体系,构建"功能化-品质化-特色化"三化标准指标体系,以"图则+清单+手册"的形式实现对绿化的分级分类管控和全覆盖指引,力求实现从"绿量"到"绿质"的精细化转变。 展开更多
关键词 绿化景观 “绿量” “绿质” 城市重点片区
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Quantity of plant leaf area on three major public squares in Kunming City, China 被引量:8
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作者 董燕 赵林森 赵宇翔 《Journal of Forestry Research》 SCIE CAS CSCD 2004年第4期291-294,共4页
Regressive formulae to calculate the quantity of plant leaf area for 13 species of ornamental plants were set up based on investigation data of 30 species on 3 major public squares (Dongfeng square, Shengli square and... Regressive formulae to calculate the quantity of plant leaf area for 13 species of ornamental plants were set up based on investigation data of 30 species on 3 major public squares (Dongfeng square, Shengli square and Guandu square) in Kun-ming City, China, which were applied to calculate quantities of plant leaf area of these 13 species. The quantities of plant leaf area for the other 17 ornamental plant species on these squares were directly measured, and the total quantity of plant leaf area of each studied square was obtained individually. The results showed that the quantity of plant leaf area on Shengli square with ornamental plants structure composed of arbor tree species, shrub tree species and turf grass was highest among the three squares. It is believed that the design model of multi-storied vertical structure and proper tending of plant community could not only increase the quantity of plant leaf area, but also play an important role in generating ecological and landscaping benefits. Some corresponding suggestions were put forward on the basis of comprehensive analyses on the plant leaf area quantity of the three representative squares in Kunming urban area. 展开更多
关键词 SQUARE Ornamental plants Quantity of plant leaf area Kunming
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Effects of Green Manure Rotation on Rice Growth Dynamics and Nitrogen Uptake and Utilization 被引量:3
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作者 张立进 杨滨娟 +2 位作者 黄国勤 陈洪俊 刘康 《Agricultural Science & Technology》 CAS 2015年第5期962-967,共6页
This study aimed to comprehensive evaluation of different winter green manure on characterization of nitrogen uptake and utilization, to provide the basis for N fertilizer reasonable operation and characteristics impr... This study aimed to comprehensive evaluation of different winter green manure on characterization of nitrogen uptake and utilization, to provide the basis for N fertilizer reasonable operation and characteristics improvement of nitrogen nutrition in rice high-yield cultivation. This experiment was set to compare milk vetch, rapeseed,ryegrass and mixed of green manure on rice yield, rice growth dynamics and nitrogen uptake and utilization in rice. The results showed that among 4 different winter green manure, the treatment of MV-R-R(milk vetch-rice-rice) for the early rice yield was the most than others treatments. Compared with RG-R-R(ryegrass-rice-rice), RPR-R(rapeseed-rice-rice), MS-R-R(mixed green manure-rice-rice), the treatment of MVR-R inceased by 6.61%, 3.29%, 0.78%, respectively. The treatment of MV-R-R in N content in plant of rice was maximized in the tillering, booting, heading and maturity periods, respectively higher than the average of other treatments 9.68%, 19.72%,6.23% and 8.66%. At tillering, booting, heading and maturity, the treatment of MV-R-R were the highest in N uptake, RP-R-R minimum. The N periodic accumulation for MV-R-R were higher than other treatments in the tillering to booting, booting to heading and heading to maturity periods. The rates respectively were 21.81%, 68.73% and286.5%. In addition, N periodic accumulation and its ratio to total in the heading to maturity was minimum, maximum before tillering under green manure rotation system.So the cropping system of milk vetch-rice-rice could increase nitrogen use efficiency and improve N cycling. 展开更多
关键词 Winter green manure Rice yield Nitrogen uptake and utilization Paddy field
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Effects of Atrazine Stress on the Growth of Pennisetum hydridum 被引量:3
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作者 张坤 李元 +2 位作者 祖艳群 陈建军 杨静 《Agricultural Science & Technology》 CAS 2011年第11期1653-1656,共4页
[Objective] This study was to investigate the effect of atrazine stress on the growth of Pennisetum hydridum. [Method] Pot experiments were conducted to study the effects of atrazine stress (20, 50, 100, 200, 500 mg... [Objective] This study was to investigate the effect of atrazine stress on the growth of Pennisetum hydridum. [Method] Pot experiments were conducted to study the effects of atrazine stress (20, 50, 100, 200, 500 mg/kg) on plant height, biomass, root-shoot ratio and chlorophyll content of P. hydridum. [Results] Low level of atrazine stress (20 and 50 mg/kg) showed no significant effects on plant height and biomass of P. hydridum. Moderate level of atrazine stress (100 and 200 mg/kg) did not show significant effect on plant height, but did on the biomass of P. hydridum. Biomass of P. hydridum stressed by 100 and 200 mg/kg of atrazine was decreased by 34.1% and 36.4% compared with control, respectively. High level of atrazine stress (500 mg/kg) brought significant decrease in plant height(by 40.6%) and biomass(20.0%) of P. hydridum. All levels of atrazine stress showed no significant effects on root-shoot ratio and chlorophyll content of P. hydridum. [Conclusion] Pennisetum hydridum has strong tolerance to atrazine stress. 展开更多
关键词 Pennisetum hydridum ATRAZINE Plant height BIOMASS Root-shoot ratio Chlorophyll content Stress tolerance
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A REMOTE SENSING MODEL FOR DETERMINING CHLOROPHYLL CONTENT AND ITS DISTRIBUTION USING LANDSAT IMAGES 被引量:5
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作者 张仁华 孙晓敏 朱治林 《Acta Botanica Sinica》 CSCD 1997年第9期821-825,共5页
The uncertainty in the estimatation of chlorophyll content with the use of normalized difference vegetation index (NDVI) has been described. To determine the chlorophyll content, model 1 for LANDSAT and model 2 for NO... The uncertainty in the estimatation of chlorophyll content with the use of normalized difference vegetation index (NDVI) has been described. To determine the chlorophyll content, model 1 for LANDSAT and model 2 for NOAA AVHRR wavebands were presented and have been verified by field experiments. Model 1 was also validated by the distribution of chlorophyll content using LANDSAT images around the Yucheng remote sensing experimental station. Using these models to estimate the chlorophyll content in the vegetation community is benefitiated by the increased precision and decreased uncertainty. 展开更多
关键词 CHLOROPHYLL Remote sensing model Vegetation index
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Physiological and Biochemical Characteristic of a Stripe Mutant with Abnormal Flower Organs in Rice 被引量:8
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作者 陈德西 马炳田 +2 位作者 王玉平 马玉清 李仕贵 《Agricultural Science & Technology》 CAS 2009年第4期15-18,共4页
[Objective] The experiment aimed to explore physiological and biochemical changes of leaves after plants were mutated. [Method] A rice double mutant with stripes on stems, leaves and spikelets were taken as experiment... [Objective] The experiment aimed to explore physiological and biochemical changes of leaves after plants were mutated. [Method] A rice double mutant with stripes on stems, leaves and spikelets were taken as experimental materials to study the enzyme activity changes in different growth stages and amino acid variation in rice. [ Result] The SOD activity in mutant was higher than that in wild plant at tillering metaphase, but lower than that in wild type before heading stage and late flowering; the POD activity in three stages increased firstly then declined and the activity showed highest maximal activity at before heading stage. However, the POD activity in wild type showed the opposite change trend; the CAT activity presented degression at three stages, especially high at tillering metaphase, but reverse changes in wild type; the MDA activity decreased at three stages, but it was still higher than that in wild type, besides, the soluble sugar content of mutant was lower, but total amino acid content was increased. [ Conclusion] The expression of mutant characteristics was correlated with SOD, POD, CAT and MDA activity Changes and these changes made the mutant survive and rice quality change at last. 展开更多
关键词 RICE STRIPE Physiological and Biochemical Characteristic Rice quality
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Effects of Different Irrigation Amounts on Wheat Growth in Arid Oasis Area 被引量:2
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作者 杨永龙 钱莉 +1 位作者 刘明春 刘惠兰 《Agricultural Science & Technology》 CAS 2010年第2期102-105,142,共5页
[Objective] The study was conducted to analyze the effects of different irrigation amount on the growth of wheat in arid oasis area and determine effective use measures and reasonable irrigation indices of water in fa... [Objective] The study was conducted to analyze the effects of different irrigation amount on the growth of wheat in arid oasis area and determine effective use measures and reasonable irrigation indices of water in farmland under arid oasis environment,so as to provide reference for the development and management of water-saving technology.[Method] Spring wheat in different growth periods was irrigated for four times.The leaf area index,dry matter content,1 000-grain weight of wheat in different growth peri... 展开更多
关键词 Arid oasis Irrigation quantity Wheat growth
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Correlation Analysis of SPAD Value with Chlorophyll Content and Economic Yield Traits of Brassica napus L. 被引量:6
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作者 高建芹 浦惠明 +4 位作者 张洁夫 龙卫华 陈锋 周晓婴 张维 《Agricultural Science & Technology》 CAS 2013年第10期1421-1428,共8页
[Objective] The aim was to compare differences of SPAD value, chloro- phyll content, agronomic characters, economic characters and yield traits to analyze correlation of SPAD value with other indices and establish reg... [Objective] The aim was to compare differences of SPAD value, chloro- phyll content, agronomic characters, economic characters and yield traits to analyze correlation of SPAD value with other indices and establish regression functions. [Method] Based on 34 Brassica napus L. varieties, SPAD value, chlorophyll content, agronomic characters, economic characters and yield traits were measured and re- gression functions were established according to correlations. [Result] SPAD value, chlorophyll content, agronomic and economic characters and yield traits all achieved significant level in differences among 34 varieties. Specifically, SPAD value was of extremely significant correlation with chlorophyll a and b, total chlorophyll and carotenoid, and the correlation from high to low was chl-b〉chl-z〉chl-a〉chl-x. SPAD value was of significantly positive correlation with total pod number per plant, plant height, seed number per pod, yield per plant and harvest yield, and of insignificant correlation with branch point height, effective branch number, pod density of main stem, and pod length. [Conclusion] It is simple and rapid to predict chlorophyll con- tent, economic characters and yields of Brassica napus L. with SPAD value and re- gression functions. 展开更多
关键词 Brassica napus L. SPAD value Chlorophyll content Economic yield Correlation analysis
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Screening for Glyphosate Resistant Wild Soybean(Glycine soja) and Study on Its Physiological Mechanisms of Resistance 被引量:2
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作者 高越 刘辉 陶波 《Agricultural Science & Technology》 CAS 2013年第9期1263-1266,共4页
[Objective] This study aimed to preliminarily determine the physiological mechanism of glyphosate resistance produced in wild soybean(Glycine soja) and further provide a basis for the breeding of glyphosate-resistan... [Objective] This study aimed to preliminarily determine the physiological mechanism of glyphosate resistance produced in wild soybean(Glycine soja) and further provide a basis for the breeding of glyphosate-resistant soybean. [Method] First,a screening for glyphosate resistant varieties among sixty-seven wild soybean materials was done in a field trial; subsequently, physiological indexes of the screened resistant variety ZYD0685 and the sensitive variety ZYD0790 were studied. [Result]At the glyphosate dose of 1.23 kg a.i/hm2, glyphoaste resistance varied greatly among different wild soybean materials, with the highest survival rate of 87% and83% occurring in ZYD0685 and ZYD2405, respectively, and that of another seven accessions ranged from 2.7% to 38%, and all the remaining fifty-eight soybean materials died. After treatment with glyphoaste at different doses, there were no significant differences in chlorophyll content and shikimate content in the resistant ZYD0685, but there was an evident increase in the activity of gultathione-S-transferases(GSTs); while in the sensitive ZYD0790, the content of shikimic acid increased significantly, and chlorophyll content decreased significantly, and GSTs activity revealed a slight change. [Conclusion] Therefore, lowering the amount of accumulated shikimic acid is the major physiological response to glyphosate in wild soybean. 展开更多
关键词 Wild soybean GLYPHOSATE Shikimic acid Chlorophyll content Gultathione-S-transferases(GSTs)
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Effects of Light, Fertilizer and Irrigation on Growth and Physiological Characteristics of Glehnia littoralis 被引量:1
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作者 彭英 汤兴利 +2 位作者 莫日江 吴群 周义峰 《Agricultural Science & Technology》 CAS 2014年第8期1351-1355,共5页
The aim was to promote the cultivation and application of medicinal plants Glehnia littoralis. [Method] Glehnia littoralis was used as experi-mental materials in this study, and orthogonal design was performed to inve... The aim was to promote the cultivation and application of medicinal plants Glehnia littoralis. [Method] Glehnia littoralis was used as experi-mental materials in this study, and orthogonal design was performed to investigate the effects of light, fertilizer and irrigation on the growth of Glehnia littoralis. The biomass, leaf chlorophyl and malondialdehyde (MDA) content were determined to study its response to light, fertilizer and irrigation. [Result] The results showed that the optimum cultivation conditions of Glehnia littoralis were not completely consistent with wild living environments. Lightly shade, highly fertilization (21.38-32.08 g) and proper irrigation (500-750 ml) were suitable for artificial cultivated Glehnia littoralis. Under the condition, the biomass was enhanced, leaf chlorophyl and carotene con-tent were increased, and MDA content changed significantly. Under stress condi-tions, the biomass of Glehnia littoralis reduced, with the decrease of chlorophyl and carotenoid content. The content of chlorophyl a was more sensitive to the variation of light, fertilizer, irrigation and other environmental factors, and MDA content signifi-cantly increased by stress conditions. [Conclusion] This research can provide refer-ence for large-scale artificial cultivation of Glehnia littoralis. 展开更多
关键词 Light Fertilizer IRRIGATION Glehnia littoralis BIOMASS Chlorophyl MDA
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Effects of Shading on Photosynthetic Properties of Canopy and Single Leaf of Winter Wheat 被引量:2
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作者 牟会荣 秦兰香 《Agricultural Science & Technology》 CAS 2012年第5期979-983,共5页
[Objective] The aim was to study on the effects of long-term low radiation on canopy apparent photosynthetic rate (CAP) and photosynthetic properties of top three leaves of winter wheat, especially the flag leaf. [M... [Objective] The aim was to study on the effects of long-term low radiation on canopy apparent photosynthetic rate (CAP) and photosynthetic properties of top three leaves of winter wheat, especially the flag leaf. [Method] Two winter wheat (Triticum aestivum L) cultivars, Yangmai 158 and Yangmai 11, which differed in low radiation resistance, were used to measure the CAP, photosynthetic rate (Pn) of the top three leaves, chlorophyll content of flag leaf and grain yield. In the test, three treatments were designed from jointing to maturity, as follows: control without shad- ing (So), S1 and S2 treatments with 22% and 33% sunshine shaded. [Result] CAP of Yangmai 158 and Yangmai 11 declined with shading. Under low radiation, Pn of flag leaf declined significantly, while no obvious effects were found on Pn of the 2nd leaf, and Pn of the 3rn leaf increased significantly, which partially compensated the decrease of Pn of the flag leaf. In addition, the compensation effect differed in shading and cultivars: compensation effect in S1 group was higher than that of S2 and effect of Yangmai 158 was higher than that of Yangmai 11. During the period of high Pn. shading decreased the content of total chlorophyll, chlorophyll a, b, and a/b. [Conclusion] Under low radiation, the decrease of chlorophyll a and a/b led to substantial declining of Pn. and CAP declined accordingly, finally resulting in drop of grain yield. The research provides important theoretical basis for wheat production in the middle and lower reaches of Yangtze River. 展开更多
关键词 Winter wheat Low radiation CAP Flag leaf Chlorophyll content
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Effects of Silicon at Different Concentrations on Morphology and Photosynthetic Physiological Mechanism of Japonica Rice 被引量:1
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作者 陈亮 蔡丽萍 +2 位作者 周彬 石妍 饶梦 《Agricultural Science & Technology》 CAS 2012年第9期1877-1880,1907,共5页
[Objective] The aim was to explore effects of silicon at different concentrations on morphology and photosynthetic physiological mechanism of japonica rice. [Method] Seedlings of japonica rice were treated with silico... [Objective] The aim was to explore effects of silicon at different concentrations on morphology and photosynthetic physiological mechanism of japonica rice. [Method] Seedlings of japonica rice were treated with silicon at different concentrations (0, 30, 80, 130 and 180 mg/L of sodium silicate); silicon contents were measured with Molybdenum blue spectrophotometric method in root, stem and leaf; plant height, root length and number in different treatment groups were measured with tools; chlorophyll a and b, and a/b in leaf and stem of rice in different groups were measured. [Result] Silicon contents in vegetative organs were as follows: stem〉leaf〉 root; when silicon was 80 mg/L, japonica ecotype was shortest; when silicon was 30 mg/L, root length of the rice was shortest and root number was least; when silicon was 30 mg/L, contents of chlorophyll a and b were highest and chlorophyll a/b achieved the peak when silicon was 80 mg/L. [Conclusion] Silicon at proper concen- tration would improve lodging-resistance and efficiency of photosynthesis, further enhancing yield of japonica rice. 展开更多
关键词 Japonica ecotype Silicon concentration Morphological characteristics Photosynthetic efficiency
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Response of seedlings of different tree species to elevated CO_2 in Changbai Mountain 被引量:1
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作者 王淼 李秋荣 +1 位作者 代力民 姬兰柱 《Journal of Forestry Research》 SCIE CAS CSCD 2003年第2期112-116,共5页
Eco-physiological responses of seedlings of eight species, Pinus koraiensis, Picea koraiensis, Larix olgensis, Populus ussuriensis, Betula platyphylla, Tilia amurensis, Traxinus mandshurica and Acer mono from broadlea... Eco-physiological responses of seedlings of eight species, Pinus koraiensis, Picea koraiensis, Larix olgensis, Populus ussuriensis, Betula platyphylla, Tilia amurensis, Traxinus mandshurica and Acer mono from broadleaved/Korean pine forest, to elevated CO2 were studied by using open-top chambers under natural sunlight in Changbai Mountain, China in two growing seasons (1998-1999). Two concentrations of CO2 were designed: elevated CO2 (700 祄olmol-1) and ambient CO2 (400 祄olmol-1). The study results showed that the height growth of the tree seedlings grown at elevated CO2 increased by about 10%-40% compared to those grown at ambient CO2. And the water using efficiency of seedlings also followed the same tendency. However, the responses of seedlings in transpiration and chlorophyll content to elevated CO2 varied with tree species. The broad-leaf tree species were more sensitive to the elevated CO2 than conifer tree species. All seedlings showed a photosynthetic acclimation to long-term elevated CO2. 展开更多
关键词 Elevated CO_2 Eco-physiological response Changbai Mountain
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Effect of 532 nm Laser Irradiation on Vc Content in Cabbage Seedlings 被引量:2
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作者 金丽虹 申炳俊 +3 位作者 刘俊华 赵新乐 李景梅 田坚 《Agricultural Science & Technology》 CAS 2009年第6期69-71,共3页
[ Objective ]The aim of this study was to discuss the feasibility of breeding cabbage with high Vc by 532 nm laser.[ Method ] With the material of cabbage, the embryo of cabbage seeds was irradiated by frequency doubl... [ Objective ]The aim of this study was to discuss the feasibility of breeding cabbage with high Vc by 532 nm laser.[ Method ] With the material of cabbage, the embryo of cabbage seeds was irradiated by frequency doubled Nd :YAG laser with different power densities and time, and the effects of laser mode on functional leaf area, chlorophyll and Vc contents in cabbage seedlings were also studied. [Result] The results showed that functional leaf area and chlorophyll content were related to laser power density and time when laser power density was 2 -20 mW/mm^2, while the optimal effect was observed at 14 mW/mm^2 for 1 min. The content of Vc in cabbage seedlings was related to dosage of laser irradiation when irradiating time ranged from 1 to 5 min, and the optimal effect was observed at 2.8 J (20 mW/mm^2, 3 min). [Conclusion] Irradiating the embryo of cabbage seeds with proper irradiation dosage of 532 nm laser can increase its effect on the Vc content significantly. 展开更多
关键词 532 nm laser irradiation Optimal irradiation dosage VC CHLOROPHYLL Functional leaf area
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Effects of Lead/Chromium Stress on Contents of Chlorophyll in Bryum argenteum and Barbula indica
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作者 汪琛颖 《Agricultural Science & Technology》 CAS 2013年第11期1587-1590,共4页
[Objective] This study aimed to clarify the effects of Pb2+ and Cr3+ stress on the contents of chlorophyl in Bryum argenteum and Barbula indica. [Method] B. ar-genteum and B. indica were cultured in different concen... [Objective] This study aimed to clarify the effects of Pb2+ and Cr3+ stress on the contents of chlorophyl in Bryum argenteum and Barbula indica. [Method] B. ar-genteum and B. indica were cultured in different concentrations of lead nitrate solu-tion or chromium chloride solution, to investigate the changes in contents of photo-synthetic pigments under lead and chromium single stress. [Result] The results showed that the effects of 1, 10 and 200 mg/L Pb2+ on B. indica were greater than those on B. argenteum; the effects of 1, 50, 100 and 200 mg/L Cr3+ on B. argen-teum were greater than those on B. indica. Total chlorophyl content in B. argen-teum and B. indica under different concentrations of Pb2+ and Cr3+ was decreased compared with that in control. The tolerance of B. indica to Pb2+ pol ution was lower than that of B. argenteum, while the tolerance of B. indica to Cr3+ pol ution was greater than that of B. argenteum. [Conclusion] Based on the conventional require-ments for monitoring materials, B. indica can be used as an indicator species to monitor heavy metal pol ution in the atmosphere of Zhengzhou. 展开更多
关键词 Bryum argenteum Barbula indica Pb2* CRY+ Heavy metal pollution Chlorophyll contents
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Effect of Radiative Forcing on Growth and Photosynthetic Responses of Elaeocarpus glabripetalus Merr.
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作者 杨爽 江洪 翟秀丽 《Agricultural Science & Technology》 CAS 2012年第6期1240-1246,共7页
[Objective] This study aimed to reveal the impact of radiative forcing on the woody plants in subtropical regions of China through the study on the effect of radiative forcing on growth and photosynthetic responses of... [Objective] This study aimed to reveal the impact of radiative forcing on the woody plants in subtropical regions of China through the study on the effect of radiative forcing on growth and photosynthetic responses of Elaecarpus glabripetalus Merr. seedlings. [Method] Three gradients of radiative forcing treatments were applied to the species namely, control group (100% natural light), weak radiative forcing group (39% natural light) and strong radiative forcing group (16% natural light). The relative contents of chlorophyll, photosynthetic parameters of E. glabripetalus in different periods were measured to analyze the effects of different gradients of radiative forcing on plant height, ground diameter, chlorophyll content, gas exchange parameters, light response cure parameters. [Result] The increased ground diameter of E. glabripetalus in different treatments was the control weak radiative forcing group strong radiative forcing group; the increased plant height in the early period was strong radiative forcing group weak radiative forcing group control, but there was no significant difference during the late period; the relative content of chlorophyll was strong radiative forcing group weak radiative forcing group control. The light compensation point (LCP), light saturation point (LSP) and the maximum net photosynthetic rate (A max ) were reduced in radiative forcing treatments. The stomatal conductance (G s ), transpiration rate (Tr) of E. glabripetalus in strong radiative forcing group were significantly smaller than that in the control group, while there was no significant change in dark respiration rate (R d ) and apparent quantum yield (AQY). [Conclusion] In summary, the radiative forcing can change the environmental factors which have significant effect on the ground diameter, plant height, relative content of chlorophyll and photosynthetic physiological parameters, but with the processing of treatment the effects on ground diameter and plant height increase are not significant in the late period, indicating that E. glabripetalus seedlings have some resistance and adaptability to the radiative forcing environment. 展开更多
关键词 Radiative forcing Elaeocarpus glabripetalus Merr. Chlorophyll relative content Photosynthetic characteristic
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Physiological and Biochemical Response of Artificial Wetland Plant under Electric Field 被引量:6
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作者 卢守波 宋新山 +2 位作者 张涛 王道源 严登华 《Agricultural Science & Technology》 CAS 2010年第5期121-124,共4页
By measuring wetland plants chlorophyll content,malondialdehyde(MDA) content and superoxide dismutase(SOD) enzyme activity,the changes of wetland plant physiological characeristics under different power strength were ... By measuring wetland plants chlorophyll content,malondialdehyde(MDA) content and superoxide dismutase(SOD) enzyme activity,the changes of wetland plant physiological characeristics under different power strength were studied,and the mechanism of electric field on plant physiological characteristics was analyzed to provide a theoretical basis for the pollutant removal ability strengthening of artificial wetland under electricfield.The results showed that compared with the control plants,low-intensity-voltage(1 V and 3 V) had no significant effect on the normal physiological and biochemical indexes of the plants,and the growth trend was better than the control group;with the voltage increasing,plant chlorophyll content,MDA content and SOD activity were greatly affected,indicating that plants were under strong oxidative stress,and the growth was damaged.Therefore,a suitable electric field could enhance the sewage treatment effect of constructed wetland. 展开更多
关键词 Electric field Artificial wetland plant Physiological and biochemical indexes Response
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CoMP-transmission-based energy-efficient scheme selection algorithm for LTE-A systems
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作者 童恩 龚淑蕾 +1 位作者 潘志文 尤肖虎 《Journal of Southeast University(English Edition)》 EI CAS 2015年第3期297-303,共7页
In order to achieve higher system energy efficiency (EE),a new coordinated multipoint (CoMP)-transmission-based scheme selection energy saving (CTSES)algorithm is proposed for downlink homogeneous cellular netwo... In order to achieve higher system energy efficiency (EE),a new coordinated multipoint (CoMP)-transmission-based scheme selection energy saving (CTSES)algorithm is proposed for downlink homogeneous cellular networks.The problem is formulated as an optimization of maximizing system EE,under the constraints of the data rate requirement and the maximum transmit power.The problem is decomposed into power allocation and alternative scheme selection problems.Optimal power allocation is calculated for CoMP-JT (joint transmission)and CoMP-CS (coordinated scheduling) transmissions,and the scheme with higher EE is chosen. Since the optimal problem is a nonlinear fractional optimization problem for both CoMP transmission schemes, the problem is transformed into an equivalent problem using the parametric method. The optimal transmit power and optimal EE are obtained by an iteration algorithm in CoMP-JT and CoMP-CS schemes.Simulation results show that the proposed algorithm offers obvious energy-saving potential and outperforms the fixed CoMP transmission scheme.Under the condition of the same maximum transmit power limit,the empirical regularity of user distribution for scheme choice is presented, and using this regularity, the computational complexity can be reduced. 展开更多
关键词 energy efficiency green radio coordinated multipoint scheme selection nonlinear fractional programming
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Kinetic Fluorescence Spectral Analysis of Core Antennas CP43 and CP47 of Photosystem Ⅱ with Ultrafast Time-resolved Technology
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作者 贺俊芳 王水才 +3 位作者 张舒 贺锋涛 单际修 匡廷云 《Acta Botanica Sinica》 CSCD 2001年第7期704-708,共5页
Ultrafast time_resolved fluorescence experiments have been performed with core antennas CP43 and CP47 of PS Ⅱ. Their dynamic fluorescence spectra were obtained with excitation wavelength 514.5 nm. For CP43, the emiss... Ultrafast time_resolved fluorescence experiments have been performed with core antennas CP43 and CP47 of PS Ⅱ. Their dynamic fluorescence spectra were obtained with excitation wavelength 514.5 nm. For CP43, the emission spectrum was found to be from 640 to 780 nm with a peak at ~680 nm and the lifetime of fluorescence was 3.54 ns. For CP47, the emission spectrum was from 630 to 775 nm with a peak at ~691 nm and the fluorescence lifetime was 3.22 ns. The fluorescence emission efficiencies of Chl a in CP43 and CP47 were calculated to be approximately 38.3% and 40.6%, respectively. The energy transfer from β_Car to Chl a in CP43 and CP47 was discussed. The rates of energy transfer from β_Car to Chl a were measured to be about 9.6×10 11 s -1 and 1.3×10 12 s -1 and energy transfer efficiencies 47.5% and 66.5% respectively. The edge_edge distances between β_Car and Chl a in CP43 and CP47 were estimated to be ~0.110 nm and ~0.085 nm respectively. 展开更多
关键词 core antenna CP43 CP47 β-Car Chl a energy transfer PS
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Effect of Two Herbicides on the Growth of Early Seedlings of Rye(Secale cereale) 被引量:2
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作者 党晨 高越 《Agricultural Science & Technology》 CAS 2011年第8期1213-1216,共4页
[Objective]The aim was to study the effect of herbicide on the growth of early seedlings of rye(Secale cereale).[Method]Effect of two kinds of herbicide(Atrazine and APM)on seedling growth of rye was investigated ... [Objective]The aim was to study the effect of herbicide on the growth of early seedlings of rye(Secale cereale).[Method]Effect of two kinds of herbicide(Atrazine and APM)on seedling growth of rye was investigated at the physiological,biochemical and cellular level.[Result]The Atrazin significantly decreased the contents of chlorophyll a,b and soluble proteins.Rye seeds were treated with 0.01-1 mg/L Atrazine for 16 h,the contents of chlorophyll a and b decreased from 1.26(a),0.49(b)mg/g FW(control)to 1.15(a),0.46(b)mg/g FW(0.1 mg/L)and 0.81(a),0.33(b)mg/g FW(1.0 mg/L).The content of soluble protein decreased with the increasing concentration of Atrazin.Atrazin had no significant influence on the cell division and chromosome structure variation.The contents of chlorophyll a,b and soluble proteins had no significantly change under the treatment of APM,but the number of chromosome structure variation such as chromosome bridge,multipolar division cells,lagging chromosome and unequal division cells increased significantly.[Conclusion]The critical concentration of Atrazine was 0.1-1.0 mg/L and 4 mg/L of APM in rye. 展开更多
关键词 HERBICIDES Secale cereal Chlorophyll content Soluble protein Chromosome structure variation
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