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不同类型棉田生态系统中棉蚜种群能量动态及其生态学效率分析 被引量:4
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作者 戈峰 丁岩钦 《生态学报》 CAS CSCD 北大核心 1995年第4期399-406,共8页
本文以能量为统一单位,以生理学时间为尺度,建立了计算世代重叠的棉蚜种群能流参数模型,分析和比较了不同播种时间、间套作、免耕和化学防治处理的棉田生态系统中棉蚜种群的生产力、摄入量及生态学效率。结果表明:(1)棉蚜种群能... 本文以能量为统一单位,以生理学时间为尺度,建立了计算世代重叠的棉蚜种群能流参数模型,分析和比较了不同播种时间、间套作、免耕和化学防治处理的棉田生态系统中棉蚜种群的生产力、摄入量及生态学效率。结果表明:(1)棉蚜种群能量生产的98%来自于伏蚜时期,而苗蚜与秋蚜不足2%;(2)播种期推后,苗蚜种群生产力、摄入量减少,而伏蚜、秋蚜的生产力、摄入量增加;套间作,使苗蚜、秋蚜种群生产力、摄入量减少,伏蚜种群的生产力、摄入量增加;(3)化学防治对棉蚜种群生产力、摄入量有一定的作用,其作用强度依农药品种及施药次数而异;(4)各类型棉田棉蚜种群的同化效率与净生态学效率变化幅度较小,而摄入利用效率变化幅度较大。由此进一步探讨了不同类型棉田棉蚜的管理对策。 展开更多
关键词 棉蚜 能量动态 生态学效率 棉田生态
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芦苇末多级利用系统的生态学效率和经济效益分析 被引量:8
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作者 李萍萍 朱忠贵 《生态学杂志》 CAS CSCD 北大核心 2002年第1期35-37,共3页
The ecological effect and economic return of the P. communis multistage utility technique was studied. P. communis residue was firstly used to culture mushroom,and then mushroom residue was used as medium of vegetable... The ecological effect and economic return of the P. communis multistage utility technique was studied. P. communis residue was firstly used to culture mushroom,and then mushroom residue was used as medium of vegetable cultivation,and finally the medium residue with vegetable root was applied to farmland as organic matter.The result showed that the assistant energy efficient is 8.1% in the mushroom culture and 8.4% in the vegetable culture.N transformation efficiency is about 40%both in mushroom and vegetable culture.The yield of both mushroom and vegetable with P. communis residue as medium are equal to the yield with conventional medium culture.For the cost of P. communis residue is much less than conventional medium,the economic return is much higher as well. 展开更多
关键词 芦苇末 菇渣 多级利用 生态学效率 经济分析 造纸废弃物
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盐碱池塘浮游植物初级生产力的研究 被引量:33
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作者 赵文 董双林 +2 位作者 李德尚 张兆琪 申屠青春 《水生生物学报》 CAS CSCD 北大核心 2003年第1期47-54,共8页
根据黑白瓶测氧法测定 ,山东省高青县赵店渔场盐碱池塘鱼类生长期内 (4— 9月 )浮游植物初级生产力为9 42± 4 2 1gO2 (m2 ·d) ,日P/B系数平均 0 2 4± 0 18,浮游植物对太阳有效辐射的利用率平均 1 5 3%。无鱼对照池浮... 根据黑白瓶测氧法测定 ,山东省高青县赵店渔场盐碱池塘鱼类生长期内 (4— 9月 )浮游植物初级生产力为9 42± 4 2 1gO2 (m2 ·d) ,日P/B系数平均 0 2 4± 0 18,浮游植物对太阳有效辐射的利用率平均 1 5 3%。无鱼对照池浮游植物初级生产力显著低于养鱼池。回归分析表明 ,浮游植物现存量、透明度、水温、盐度是决定盐碱池塘浮游植物初级生产力的主要生态因子。营养盐中磷比氮的限制作用大。文中探讨了养鱼池初级生产力在能量转化中的生态学效率。 展开更多
关键词 生态学效率 盐碱池塘 浮游植物 初级生产力
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Application of ecological footprint in ecological industrial systems:a study case of maize-MSG production systems
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作者 Yah Lizhen Cheng Shengkui +1 位作者 Min Qingwen Sun Yehong 《Ecological Economy》 2007年第1期8-17,共10页
To improve the comparability of the research results of ecological industry, the ecological footprint is appliedto analyze the resource utilization and environmental pollution in various subsystems, taking maize-MSG a... To improve the comparability of the research results of ecological industry, the ecological footprint is appliedto analyze the resource utilization and environmental pollution in various subsystems, taking maize-MSG as a case.Results show that the production process from maize to MSG is a extended process of ecological footprint, and that theecological footprint of the maize production is the biggest; the extension of ecological footprint is followed by the increaseof footprint profit, which means that the extension of production chain is an important method to improve the resourcesprofit; the systems have a big proportion of the indirect energy ecological footprint; the air and water pollution in MSGsubsystem is the most serious. At last, it can be identified that ecological footprint is a good method to measure resourceutilization and environmental pollution in various subsystems of an integrated ecological industry. 展开更多
关键词 Ecological footprint MSG production Efficiency of resources Ecological industry
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Assessment and Guidelines to Improve Eco-efficiency and Indoor Comfort at University of Passo Fundo, Brazil
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作者 Marcos Antonio Leite Frandoloso Luciana Londero Brandli 《Journal of Civil Engineering and Architecture》 2015年第2期179-187,共9页
The paper deals with the energy and indoor comfort on buildings of UPF (University ofPasso Fundo), located in southern Brazil, in order to improve the eco-efficiency concepts in the university's building stock, rei... The paper deals with the energy and indoor comfort on buildings of UPF (University ofPasso Fundo), located in southern Brazil, in order to improve the eco-efficiency concepts in the university's building stock, reinforcing its responsibility towards sustainable development. The factors that affect thermal performance and the energy consumption of two case studies were identified, including the general characteristics of the envelope and the indoor conditions. The simulations with DesignBuilder software compare the energy and thermal performance of both cases: those results allow the identification of their positive and negative aspects, as well as making a co-relation with the students' sensations of comfort--obtained through PMV (predicted mean vote). The research indicates that it will be possible to improve eco-efficiency of existing and new buildings and campuses by retrofitting and upgrading it with regard to better indoor conditions that really correspond to climate conditions (hot and humid summers, and cold and damp winters), using passive strategies for heating and cooling and at the same time to improve rational use of natural resources and to reduce the environmental impact. Probably, giving comfortable conditions to the users will increase energy consumption, but there is a potential reduction of lighting and equipment that could minimize this impact. 展开更多
关键词 Comfort energy efficiency ECO-EFFICIENCY indoor comfort university buildings building retrofitting.
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Effect of atmospheric aerosol on surface ozone variation over the Pearl River Delta region 被引量:10
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作者 DENG XueJiao ZHOU XiuJi +6 位作者 WU Dui TIE XueXi TAN HaoBo LI Fei BI XueYan DENG Tao JIANG DeHai 《Science China Earth Sciences》 SCIE EI CAS 2011年第5期744-752,共9页
Our analysis of the surface aerosol and ultraviolet (UV) measurements in Pearl River Delta (PRD) region shows that the surface UV radiation is reduced by more than 50% due to high aerosol concentrations. This has ... Our analysis of the surface aerosol and ultraviolet (UV) measurements in Pearl River Delta (PRD) region shows that the surface UV radiation is reduced by more than 50% due to high aerosol concentrations. This has important impacts on urban ecosystem and photochemistry, especially on ozone photochemical production over the region. The quantitative effect of aerosols on surface ozone is evaluated by analyzing surface observations (including ozone, ultraviolet radiation, aerosol radiative parameters) and by using radiative and chemical models. A case study shows that the aerosol concentrations and UV radiation are significantly correlated with ozone concentrations. The correlation coefficient between the aerosol optical depth (AOD) and the PM10 mass concentration is very high, with a maximum of 0.98, and the AOD and UV radiation/ozone is anti- correlated, with a correlation coefficient of-0.90. The analysis suggests that ozone productivity is significantly decreased due to the reduction of UV radiation. The noon-time ozone maximum is considerably depressed when AOD is 0.6, and is further decreased when AOD is up to 1.2 due to the reduction of ozone photochemical productivity. Because the occurring probability of aerosol optical depth for AOD550m≥0.6 and AOD340mm ≥1.0 is 47, and 55% respectively during the dry season (October, November, December, January), this heavy aerosol condition explains the low ozone maximum that often occurs in the dry season over the Guangzhou region. The analysis also suggests that the value of single scattering albedo (SSA) is very sensitive to the aerosol radiative effect when the radiative and chemical models are applied, implying that the value of SSA needs to be carefully studied when the models are used in calculating ozone production. 展开更多
关键词 atmospheric aerosol OZONE photochemical process ATTENUATION
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Thermodynamic performance of Dual-Miller cycle(DMC) with polytropic processes based on power output, thermal efficiency and ecological function 被引量:11
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作者 YOU Jiang CHEN LinGen +1 位作者 WU ZhiXiang SUN FengRui 《Science China(Technological Sciences)》 SCIE EI CAS CSCD 2018年第3期453-463,共11页
This study reports a new model of an air standard Dual-Miller cycle(DMC) with two polytropic processes and heat transfer loss.The two reversible adiabatic processes which could not be realized in practice are replaced... This study reports a new model of an air standard Dual-Miller cycle(DMC) with two polytropic processes and heat transfer loss.The two reversible adiabatic processes which could not be realized in practice are replaced with two polytropic processes in order to more accurately reflect the practical working performance. The heat transfer loss is taken into account. The expressions of power output, thermal efficiency, entropy generation rate(EGR) and ecological function are addressed using finite-time thermodynamic theory. Through numerical calculations, the influences of compression ratio, cut-off ratio and polytropic exponent on the performance are thermodynamically analyzed. The model can be simplified to other cycle models under specific conditions, which means the results have an certain universality and may be helpful in the design of practical heat engines. It is shown that the entropy generation minimization does not always lead to the best system performance. 展开更多
关键词 Dual-Miller cycle polytropic process power output thermal efficiency ecological function finite-time thermodynamics
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