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北京市25种公路绿化植物及配置模式的绿量 被引量:2
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作者 宋子炜 郭小平 马武昌 《城市环境与城市生态》 CAS CSCD 2008年第5期25-28,共4页
计量研究公路绿地的生态服务功能有助于科学评估公路绿化的无形价值。以北京市顺义区顺平路(S305)的绿化植物群落为研究对象,运用WinScanopy For Canopy Analysis冠层分析仪采集数据,研究了公路绿化常见植物及配置模式的绿量率,并建立... 计量研究公路绿地的生态服务功能有助于科学评估公路绿化的无形价值。以北京市顺义区顺平路(S305)的绿化植物群落为研究对象,运用WinScanopy For Canopy Analysis冠层分析仪采集数据,研究了公路绿化常见植物及配置模式的绿量率,并建立了25种公路绿化常见植物的绿量率模型,以期为公路绿化树种选择和群落配置提供基础分析与参考。结果表明:阔叶乔木的绿量率在3.02~4.80之间,针叶乔木的绿量率集中在4~6之间,灌木植物的绿量率较小,种植紧凑的绿篱绿量率达到3.94;不同配置模式的群落绿量率大小顺序依次为:针阔混交林】阔叶林】针叶林】灌木群落。其研究结果为公路绿化建设和绿地生态效益的计量提供了科学依据。 展开更多
关键词 公路绿 植物群落 WinScanopy 绿量率 生态服务价值
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北京市平原区公路绿化绿量测算 被引量:2
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作者 宋子炜 马武昌 郭小平 《林业科技开发》 2008年第5期28-31,共4页
对公路绿地生态服务功能进行计量研究有助于对公路绿化无形价值的深入了解。以北京市顺义区顺平路(S305)的绿化植物群落为研究对象,运用WinSCANOPY For Canopy Analysis冠层分析仪采集数据,研究了常见公路绿化植物及配置模式的绿量率,... 对公路绿地生态服务功能进行计量研究有助于对公路绿化无形价值的深入了解。以北京市顺义区顺平路(S305)的绿化植物群落为研究对象,运用WinSCANOPY For Canopy Analysis冠层分析仪采集数据,研究了常见公路绿化植物及配置模式的绿量率,并建立了25种常见公路绿化植物的绿量率模型,以期为公路绿化树种选择和群落配置提供基础分析与参考。结果表明:阔叶乔木的绿量率在3.02~4.80之间,针叶乔木的绿量率集中在4~6之间,灌木植物的绿量率较小,但是种植紧凑的绿篱绿量率达到3.94。不同配置模式的群落绿量率大小顺序依次为:针阔混交林>阔叶林>针叶林>灌木群落。其研究结果为公路绿化建设和绿地生态效益的计量提供了科学依据。 展开更多
关键词 公路绿 绿量率 生态服务价值
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绿量概念在公路绿化中的应用及实现途径 被引量:2
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作者 宋子炜 郭小平 马武昌 《山西水土保持科技》 2008年第4期1-3,共3页
公路建设在促进经济发展的同时,极易引起环境破坏、水土流失等问题,路域生态环境恢复受到广泛重视。公路绿化建设是改善路域生态环境不可或缺的环节,绿化生态效益发挥决定于植物的选择与配置。在我国,公路绿化存在重景观、轻生态功能的... 公路建设在促进经济发展的同时,极易引起环境破坏、水土流失等问题,路域生态环境恢复受到广泛重视。公路绿化建设是改善路域生态环境不可或缺的环节,绿化生态效益发挥决定于植物的选择与配置。在我国,公路绿化存在重景观、轻生态功能的倾向,难以最大限度发挥绿色植物的自然生产能力。很多学者强调应该充分利用有限的公路绿化用地,合理配置植物,以增强其抗干扰能力,降低养护成本。因此,运用新型绿化指标衡量公路绿化生态效益、考量企业绿化绩效,对于指导公路绿化建设具有积极意义。笔者尝试将绿量概念引入到公路绿化建设中,详细阐述了绿量的含义与计算方法,并结合实际情况提出了实现途径。 展开更多
关键词 公路绿 绿量率 绿 生态效益
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“绿量”概念在公路绿化中的应用及实现途径 被引量:2
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作者 马武昌 邹定保 《公路交通技术》 2008年第5期146-148,152,共4页
公路绿化是改善路域生态环境不可或缺的环节,其生态效益发挥决定于植物的选择与配置。在我国,公路绿化存在重景观、轻生态功能的倾向,难以最大限度发挥绿色植物的自然生产能力。因此,运用新型绿化指标衡量公路绿化生态效益、考量企业绿... 公路绿化是改善路域生态环境不可或缺的环节,其生态效益发挥决定于植物的选择与配置。在我国,公路绿化存在重景观、轻生态功能的倾向,难以最大限度发挥绿色植物的自然生产能力。因此,运用新型绿化指标衡量公路绿化生态效益、考量企业绿化绩效,对于指导公路绿化建设具有积极意义。将绿量概念引入到公路绿化建设中,详细阐述绿量的含义与计算方法,并提出实现途径。 展开更多
关键词 公路绿 绿量率 绿 生态效益
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北京市平原区公路绿化绿量研究
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作者 宋子炜 郭小平 马武昌 《吉林林业科技》 2008年第4期11-15,共5页
以北京市顺义区顺平路(S305)的绿化植物群落为研究对象,运用WinSCANOPY冠层分析仪采集数据,研究常见公路绿化植物及配置模式的绿量率,并建立了25种常见公路绿化植物的绿量率模型,以期为公路绿化树种选择和群落配置提供基础分析与参考。... 以北京市顺义区顺平路(S305)的绿化植物群落为研究对象,运用WinSCANOPY冠层分析仪采集数据,研究常见公路绿化植物及配置模式的绿量率,并建立了25种常见公路绿化植物的绿量率模型,以期为公路绿化树种选择和群落配置提供基础分析与参考。结果表明:阔叶乔木的绿量率在3.02~4.80之间,针叶乔木的绿量率集中在4.00~6.00之间,灌木植物的绿量率较小,但是种植紧凑的绿篱绿量率达到3.94;不同配置模式的群落绿量率大小顺序依次为:针阔混交林>阔叶林>针叶林>灌木群落。 展开更多
关键词 公路绿 WinSCANOPY 绿量率 生态服务价值
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城市绿地系统的生态规划方法初探 被引量:27
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作者 韩晓莉 宋功明 王军 《西安建筑科技大学学报(自然科学版)》 CSCD 2003年第2期127-130,共4页
城市绿地系统 ,作为城市人工环境中的自然要素 ,对城市生态系统起着重要的调节作用 .但目前城市绿地系统规划的指标体系主要以定性分析为主 ,量化指标则基于静态统计数据 ,千城一律 ,统一定额 ,很难体现城市的地域生态特色 ,同时在建设... 城市绿地系统 ,作为城市人工环境中的自然要素 ,对城市生态系统起着重要的调节作用 .但目前城市绿地系统规划的指标体系主要以定性分析为主 ,量化指标则基于静态统计数据 ,千城一律 ,统一定额 ,很难体现城市的地域生态特色 ,同时在建设和管理上也缺乏具体措施 .本文从景观生态学的角度 ,探讨城市绿地系统的生态平衡功能 ,寻找符合景观生态学要求的城市绿地系统的规划方法 ,量化指标 。 展开更多
关键词 城市绿地系统 景观生态学 绿量率 碳氧平衡
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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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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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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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Land Use Structure in Wuhai City on Basis of Ecological Green Equivalence
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作者 李萍 孙泰森 《Agricultural Science & Technology》 CAS 2015年第6期1276-1279,共4页
The paper took Wuhai District as an example, bases on the contrast be-tween the land use condition in 2005 and 2010, and applied the ecological green equivalence to establish a mathematic model of ecological optimizat... The paper took Wuhai District as an example, bases on the contrast be-tween the land use condition in 2005 and 2010, and applied the ecological green equivalence to establish a mathematic model of ecological optimization of land use structure, to establish the ecology green equivalent mathematical model and survey the value of region green equivalent, and then assess the ecological environment situation. The results show that the ecological environment has been deteriorated in Wuhai from 2005 to 2010, so the ecological environment was poor. In order to in-crease eco-efficiency of land use, garden, urban green space and woodland area should be raised in the optimization program. 展开更多
关键词 Ecological green equivalence Forest coverage rate Land use structure Wuhai city
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Effects of salinity and nutrients on the growth and chlorophyll fluorescence of Caulerpa lentillifera 被引量:9
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作者 郭辉 姚建亭 +1 位作者 孙忠民 段德麟 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2015年第2期410-418,共9页
Caulerpa lentillifera is a green algae that distributes worldwide and is cultivated for food. We assessed vegetative propagation of C. lentillifera by measuring the specific growth rate (SGR) and chlorophyll fluores... Caulerpa lentillifera is a green algae that distributes worldwide and is cultivated for food. We assessed vegetative propagation of C. lentillifera by measuring the specific growth rate (SGR) and chlorophyll fluorescence of the green algae cultured at different salinities and nutrient levels. The results indicated that C. lentillifera can survive in salinities ranging from 20 to 50, and can develop at salinities of 30 to 40. The maximum SGR for C. lentillifera occurred at a salinity of 35. Both chlorophyll content and the ratio of variable to maximum fluorescence (F_v/F_m) were also at a maximum at a salinity of 35. Photosynthesis was inhibited in salinities greater than 45 and less than 25. Both the maximum SGR and maximum chlorophyll content were found in algae treated with a concentration of 0.5 mmol/L of NO3-N and 0.1 mmol/L of PO_4-P. The photosynthetic capacity of photosystem Ⅱ (PSⅡ) was inhibited in cultures of C. lentillifera at high nutrient levels. This occurred when NO_3-N concentrations were greater than 1.0 mmol/L and when PO4-P concentrations were at 0.4 mmol/L. As there is strong need for large-scale cultivation of C. lentillifera, these data contribute important information to ensure optimal results. 展开更多
关键词 Caulerpa lentillifera SALINITY nutrient level specific growth rate (SGR) ratio of variable tomaximum fluorescence (F_v/F_m) non-photochemical quenching (NPQ)
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中国城市绿地系统规划评价指标体系的研究 被引量:130
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作者 刘滨谊 姜允芳 《城市规划汇刊》 CSSCI CSCD 北大核心 2002年第2期27-29,共3页
分析中国目前城市绿地系统规划指标存在问题 ,探讨建立城市绿地系统指标体系确定的原则和指标体系 ,提出以绿量率为代表的生态、立体绿化的新观念。
关键词 城市 生态绿地系统 绿 绿量率 中国
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Effect of flow rate on environmental variables and phytoplankton dynamics:results from field enclosures 被引量:3
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作者 张海平 陈瑞弘 +1 位作者 李飞鹏 陈玲 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2015年第2期430-438,共9页
To investigate the effects of flow rate on phytoplankton dynamics and related environment variables,a set of enclosure experiments with different fl ow rates were conducted in an artificial lake. We monitored nutrient... To investigate the effects of flow rate on phytoplankton dynamics and related environment variables,a set of enclosure experiments with different fl ow rates were conducted in an artificial lake. We monitored nutrients,temperature,dissolved oxygen,p H,conductivity,turbidity,chlorophyll-a and phytoplankton levels. The lower biomass in all flowing enclosures showed that flow rate significantly inhibited the growth of phytoplankton. A critical flow rate occurred near 0.06 m/s,which was the lowest relative inhibitory rate. Changes in flow conditions affected algal competition for light,resulting in a dramatic shift in phytoplankton composition,from blue-green algae in still waters to green algae in flowing conditions. These findings indicate that critical flow rate can be useful in developing methods to reduce algal bloom occurrence. However,flow rate significantly enhanced the inter-relationships among environmental variables,in particular by inducing higher water turbidity and vegetative reproduction of periphyton( Spirogyra). These changes were accompanied by a decrease in underwater light intensity,which consequently inhibited the photosynthetic intensity of phytoplankton. These results warn that a universal critical flow rate might not exist,because the effect of flow rate on phytoplankton is interlinked with many other environmental variables. 展开更多
关键词 environmental variables PHYTOPLANKTON enclosure experiment flow rate
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A field study on the conversion ratio of phytoplankton biomass carbon to chlorophyll-a in Jiaozhou Bay,China 被引量:4
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作者 吕淑果 王旭晨 韩博平 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2009年第4期793-805,共13页
A one-year field study was conducted to determine the conversion ratio of phytoplankton biomass carbon (Phyto-C) to chlorophyll-a (Chl-a) in Jiaozhou Bay, China. We measured suspended particulate organic carbon (... A one-year field study was conducted to determine the conversion ratio of phytoplankton biomass carbon (Phyto-C) to chlorophyll-a (Chl-a) in Jiaozhou Bay, China. We measured suspended particulate organic carbon (POC) and phytoplankton Chl-a samples collected in surface water monthly from March 2005 to February 2006. The temporal and spatial variations of Chl-a and POC concentrations were observed in the bay. Based on the field measurements, a linear regression model Ⅱwas used to generate the conversion ratio of Phyto-C to Chl-a. In most cases, a good linear correlation was found between the observed POC and Chl-a concentrations, and the calculated conversion ratios ranged from 26 to 250 with a mean value of 56 μg ·μl^-1. The conversion ratio in the fall was higher than that in the winter and spring months, and had the lowest values in the summer. The ratios also exhibited spatial variations, generally with low values in the near shore regions and relatively high values in offshore waters. Our study suggests that temperature was likely to be the main factor influencing the observed seasonal variations of conversion ratios while nutrient supply and light penetration played important roles in controlling the spatial variations. 展开更多
关键词 CHLOROPHYLL-A Phyto-C/Chl-a ratio suspended particulate organic carbon Model II regression Jiaozhou Bay
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Effect of Removing the Lower Leaves on the Physiological Features and Aroma Constituents of Flue-Cured Tobacco
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作者 Jiang Hou Long Huang Fu Rao +6 位作者 Ran Hui Wen Xu Chen Wang Dai Bin Yang Chao Wang Hong Feng Cheng Hai Tao Liu Guo Shun 《Journal of Agricultural Science and Technology(B)》 2014年第9期722-730,共9页
Yunyan 97 was selected as the raw material. The effects of removing different number (0, 2, 3 and 4) of lower leaves on root activity, chlorophyll content, physiological features and contents of neutral aroma consti... Yunyan 97 was selected as the raw material. The effects of removing different number (0, 2, 3 and 4) of lower leaves on root activity, chlorophyll content, physiological features and contents of neutral aroma constituents in the flue-cured tobacco were analyzed. The results showed that the removal of lower leaves could significantly increase the root activity, chlorophyll content, net photosynthetic rate (Pn) and transpiration rate (Tr), and delay the photosynthetic functional decline. Such effects were the greatest in lower leaves, followed by middle leaves and upper leaves. Moreover, the degree of the effects increased with higher number of leaves removed. After She lower leaves were removed, the water use efficiency (WUE) of leaves in the first 10 d became higher with more leaves removed. In the later periods (24 d, 38 d), WUE decreased with more leaves removed. For the middle and upper leaves, the removal of three leaves (T2) and two leaves (T1) resulted in the highest contents of aroma constituents, respectively. For the tobaccos cultured in soil with moderate fertility under the experimental conditions, the appropriate number of lower leaves removed should be 2-3. 展开更多
关键词 Physiological features aroma constituents flue-cured tobacco.
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Detecting Chlorophyll a Concentration and Bloom Patterns at Upwelling Area in South Central Vietnam by High Resolution Multi-satellite Data
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作者 Tong Phuoc Hoang Son Truong Minh Chuan Hoang Cong Tin 《Journal of Environmental Science and Engineering(A)》 2015年第5期215-224,共10页
Study on Chlorophyll a (Chl. a) distribution and bloom patterns is essential in the upwelling areas that constitute the main fishery grounds of Vietnam. Based on high resolution satellite imagery and monthly in-situ... Study on Chlorophyll a (Chl. a) distribution and bloom patterns is essential in the upwelling areas that constitute the main fishery grounds of Vietnam. Based on high resolution satellite imagery and monthly in-situ data in period from 2007 to 2008, the spatial and temporal variations ofChl, a in the upwelling region including algal blooms have been detected. Anomalies of higher Chl. a concentration and bloom patterns occurred at different periods, locations, and bloom shapes in coastal waters of Southern Center of Vietnam. The appearances of these bloom are related to four difference reasons, such as: (i) Their locations coincided to main center of upwelling phenomena that usually occur during southwest monsoon (SWM); (ii) Effect of northeast monsoon (NEM) that brings and attaches the nutrient into the coast and created "floating" algae bloom patches in coastal zones; (iii) The algae blooms can be potentially associated with Harmful Algae Bloom (HAB) during the SWM or local eddies during NEM and (iv) Their appearances are also as a result of distinctive nutrient inflow fi'om Mekong delta and pumping of nutrients by internal waves in coastal shallow waters. 展开更多
关键词 Chlorophyll a bloom pattern fisheries resources coastal waters remote sensing upwelling.
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