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1.
福建武夷山甜槠群落能量的研究   总被引:43,自引:0,他引:43  
在生物量、生产力研究基础上,对武夷山甜槠(Castanopsis eyrei(Cham p.ex Benth.) Tutch.)群落各组分的热值、群落能量现存量、能量年净固定量以及太阳能转化效率进行了研究。结果表明:(1)甜槠群落各组分样品的干重热值具有一定的差异,树皮热值最高,细根热值最低。(2)甜槠群落的能量现存量达780584.1 kJ·m - 2,其中地上部分为678913.8 kJ·m - 2,占总量的86.98% ;地下部分为101670.3 kJ·m - 2,占13.02% 。(3)甜槠群落的能量年净固定量(1992年)为26856.2 kJ·m - 2·a- 1,林地太阳光合有效辐射能的转化效率为1.296% 。  相似文献   

2.
亚热带山地突脉青冈群落能量的研究   总被引:1,自引:0,他引:1  
对突脉青冈(Cyclobalanopsiselevaticostata)群落植物体各组分的热值、群落能量现存量、能量年净固定量和太阳能转化效率的研究结果表明:该群落植物体各组分样品的干重热值具有一定差异,树皮热值最高,细根热值最低。突脉青同群落的能量现存量852058kJm-2,其中地上部分741416kJm-2,占总量的87.01%;地下部分110642kJm-2,占12.99%。突脉青冈1996年群落能量净固定量为28273kJm-2,林地太阳光有效辐射能转化效率1.35%。  相似文献   

3.
武夷山黄山松群落能量的研究   总被引:19,自引:2,他引:17  
在生物量,生产力研究的基础上,通过干重热值测定,对黄山松(Pinustaiwanensis)群落的能量现存量,能量净固定量及太阳能转化效率进行分析讨论,测定结果表明,(1)黄山松群各组分样品的干重热值具有一定的差异,树皮的干重热值最高,为22.14kJ/g,枯根的干重热最低,为16.27kJ/g。(2)黄山松群落的能量现存量为379832.3kJ/m^2,其中地上部分为275488.0kJ/m^2  相似文献   

4.
鹤山南亚热带草坡生态系统的太阳辐射能环境   总被引:4,自引:1,他引:3  
本文以鹤山丘陵综合试验站草坡为研究对象,分析了鹤山南亚热带草坡多年的辐射能环境.揭示了辐射与环境的关系,主要结果如下:1.全年抵达草坡的太阳总辐射约4775.2MJm-2a-1,其中直接辐射为3134.1MJm-2a-1,散射辐射为1441.1MJm-2a-1.它们受太阳高度角、云量、大气透明系数和大气光学特性的影响较大.2.太阳总辐射、直射的月变化呈双峰曲线,5月和8月为峰值,2月和6月为谷值.3.全年草坡的反射辐射量为822.5MJm-2a-1.群落的年均反射率为17.2%,其月变化因入射光特性和群落的发育状况的不同而变化.4.草坡的净辐射力2915.6MJm-2a-1,占总辐射的61.1%.其最大值出现在5月,为380.2MJm-2a-1,最低值出现在2月,为129.3MJm-2a-1,7-9月比较稳定且值相对较高.5.群落发育成熟后,其对太阳辐射的截获能力很强.其透射率仅17.2%,其冠层截获率为65.4%.  相似文献   

5.
虾池生态系能量收支和流动的初步分析   总被引:12,自引:0,他引:12  
周一兵 《生态学报》2000,20(3):474-481
根据日本刺沙蚕作为动物性活饵在虾池食物链中的作用,对虾池生态系中的有机质收支,生物能量流动及其转化效率进行了分析。结果表明,虾池在养殖期间输入和合成的有机质能量为13725.14kJ/m^2,其中,初级产量为7523.82kJ/m^2,约占总输入的55%。有机质在养殖期间的支出量平均10359.38kJ/m^2,其中,生物呼吸7988.49kJ/m^2,占总支出的77%;对虾产量平均874.48k  相似文献   

6.
增强UV—B辐射对蚕豆叶片微粒体膜一些性质的影响   总被引:11,自引:0,他引:11  
温室条件下,用0,8.65kJm^-2d^-1及11.2kJm^-2d^-1不同剂量的UV-B辐射处理蚕豆幼苗。Ca^2+-ATPase及Mg^2+-ATPase的活性在辐射处理期间下降。在处理21d,T1和T2微粒体膜的MDA含量明显高于对照,同时IUFA急剧下降,且呈明显的剂量效应。  相似文献   

7.
黄淮海平原豫北地区农林业系统的能量研究   总被引:9,自引:0,他引:9  
对黄淮海平原豫北地区农林业系统3种群落类型(沙兰杨-小麦·玉米(POTZ)、泡桐-小麦·玉米(PATZ)和苹果-小麦·花生(MTA))进行了研究,结果表明,POTZ类型的年群落净固定能量为43.6235×1010J·ha-1,PATZ为45.6426×1010J·ha-1,MTA为49.6000×1010J·ha-1.年群落现存能量分别为55.2174×1010,57.7595×1010和78.4699×1010J·ha-1;群落的光能利用率分别为1.000,1.047和1.138%.群落的能量效率分别比传统的农田系统增加11.83、14.45和28.25%.在农业林业系统中,苹果-小麦·花生群落类型为最佳群落类型.  相似文献   

8.
鼎湖山自然保护区3种群落的能量流和能量利用效率   总被引:11,自引:2,他引:9  
根据鼎湖山定位观察站多年的实验数据,综合分析鼎湖山自然依据区内季风常绿阔叶林、针阔混交林和马尾松林3种群落的能量模式,取得森林生态系统各组分之间能量交换的流向和流量,并求出3个群落的几种能量利用效率。研究结果表明,从能量交换强度看,季风常绿阔叶林最大,群落每年吸收的PAR达1685MJ/m^2,占投射到林冠上PAR的93.7%,针阔混交林次之,吸收率为87.9%,针叶林最少,呼吸率只有40.0%.  相似文献   

9.
鹤山马占相思人工林的生物量和净初级生产力   总被引:23,自引:0,他引:23       下载免费PDF全文
通过对鹤山马占相思(Acacia mangium)人工林的群落结构,生物量、净初级生产力的研究表明,15龄的马占相思人工林乔木层总生物量为196.94t.hm^-2,其中树干为80.75t.hm^-2,树枝为55.14t.hm^-2,树叶为19.69t.hm^-2,根为41.36t.hm^-2,该人工林1-7龄生物量增长迅速,而7-11龄的生物量增则相对较慢,11龄后生物量趋。11龄马占相思林的净  相似文献   

10.
鹤山湿地松人工林的群落结构与能量特征   总被引:4,自引:0,他引:4  
曹洪麟  任海  彭少麟   《广西植物》1998,18(1):24-28
在调查一个10年生湿地松人工纯林的基础上,用林木收获法和相关生长法测定该群落的生物量和能量分配。结果表明:本群落组成种类少,结构简单,林分的生长中心也是其能量分布中心,群落的生物量和能量现存量分别为10903t/hm2和9505MJ/m2。这些值均低于同站7年生马占相思林,可以将该群落改造成针阔混交林,以提高林分的光能利用率。  相似文献   

11.
能量效率与可更新能源   总被引:2,自引:0,他引:2  
陈盖  蓝盛芳 《生态科学》2001,20(Z1):65-69
一些可更新能源可减少甚至消除我们对化石能和核能的依赖,其中很多虽然已为人类使用数百年,但因为化石能的普遍使用,一直都为起人类的注意。人类已发明了新技术来利用这些可更新能源。其利用有赖于一定的技术是既定的事实,目前有成功建立这样的能源工业还是十分昂贵的。如果人类生产经济和市场允许的话,这些新技术经进一步改进和简化后,就可以降低成本,并且应用起来也很可靠。相对于开发应用核能,水能和化石能数以百万计的投资耗费来讲,用于可更新资源的资金可谓微乎其微。虽然传统能源和替代能源各具优点,但保护能源往往还是解决能源短缺最便宜,最容易的途径。  相似文献   

12.
陈盖  蓝盛芳 《生态科学》2001,20(1):65-69
一可更新能源可减少甚至消除我们对化石能和核能的依赖,其中很多虽然已为人类使用数百年,但因为石能的普遍使用,一直都为起人类的注意。人类已发明了新技术利用这些可更新能源。其利用不赖于一定的技术是既定的事实,目前有成功建立这样的能源工业还是十分昂贵的。如果人类生产经济和市场允许的话,这些新的技术经进一步改进和简化后,就可以降低成本,并且应用起来也很可靠。相对于开发应用核能,水能和化石能数以百万计的投资耗费来讲,用于可更新资源的资金可谓微乎其微。虽然传统能源和替代能源各具优点,但保护能源往往还是解决能源短缺最便宜,最容易的途径。  相似文献   

13.
14.
Skutterudites are promising thermoelectric materials because of their high figure of merit, ZT, and good thermomechanical properties. This work reports the effective figure of merit, ZTeff, and the efficiency of skutterudite legs and a unicouple working under a large temperature difference. The p‐ and n‐type legs are fabricated with electrodes sintered directly to the skutterudite during a hot pressing process. CoSi2 is used as the electrode for the n‐type skutterudite (Yb0.35Co4Sb12) and Co2Si for the p‐type skutterudite (NdFe3.5Co0.5Sb12). A technique is developed to measure the ZTeff of individual legs and the efficiency of a unicouple. An ZTeff of 0.74 is determined for the n‐type legs operating between 52 and 595 °C, and an ZTeff of 0.51 for the p‐type legs operating between 77 and 600 °C. The efficiency of the p–n unicouple is determined to be 9.1% operating between ~70 and 550 °C.  相似文献   

15.
The conversion and transmission of blue energy in the ocean are critical issues. By employing triboelectric nanogenerators (TENGs), blue energy can be harvested but the corresponding electricity transmission and storage are still great challenges. In this work, an automatic high‐efficiency self‐powered energy collection and conversion system is proposed that converts blue energy to chemical energy. A gear‐driven unidirectional acceleration TENG is designed to convert disordered and low‐frequency water wave energy to low voltage and high current DC output. The output bias from the TENG can be used to drive a Ti–Fe2O3/FeNiOOH based photoelectrochemical cell under sunlight to produce hydrogen. Moreover, under the situation without sunlight, the self‐powered system can be automatically switched to another working state to charge a Co3O4 based lithium‐ion battery. The hydrogen production rate reaches to 4.65 µL min‐1 under sunlight at the rotation speed of 120 rpm. The conversion efficiency of the whole system is calculated to be 2.29%. The system triggered by photoswitches can automatically switch between two working states with or without sunlight and convert the blue energy to either hydrogen energy or battery energy for easy storage and transmission, which widens the future applications for blue energy.  相似文献   

16.
Mean risk magnitude judgments expressed by Belgian and French students on 107 items combining a particular energy domain (wood and biomass, coal, gas, oil, nuclear, water, wind, geothermal and solar) and a particular aspect of the energy production process (obtaining raw materials, storage of raw materials, transport of raw materials, energy production, waste products related to energy production, energy transport, waste products transport, waste products storage, utilization of energy) are reported, and analyzed. Questions were of the form: What is the level of risk (for health and the environment) associated with the item “Electrical energy production by thermodynamic conversion”? Concerning energy domains, nuclear energy received the highest ratings, almost regardless of the aspect of the energy production process considered (from the extraction of raw materials to the storage of production wastes). This was followed by oil, obtaining the next highest ratings after those for nuclear energy, then gas, considered more risky than biomass and coal. The brand image of these two latter energy sources would be almost as positive as that of water, solar, geothermal and wind energy if a solution could be found to the problem of atmospheric emission of carbon monoxide. Concerning production process aspects, waste products (as well as the transport and storage of waste) received the highest ratings. This is not unrelated to the fact that the vast majority of studies devoted to a particular area or particular aspect have concerned nuclear waste. In contrast, no very high degree of concern was found regarding the energy (electrical) transport aspect.  相似文献   

17.
中国小麦燃料乙醇的能量收益   总被引:1,自引:0,他引:1  
李胜  路明  杜凤光 《生态学报》2007,27(9):3794-3800
分析了燃料乙醇能量收益问题提出的背景,国外有关燃料乙醇能量收益研究的最新进展及国内研究现状,采用全生命周期分析方法,计算了小麦燃料乙醇净能量值和能量产投比,对中国小麦燃料乙醇的能量收益进行了评价。主要结论有:如不考虑副产品能量价值,旧工艺和新工艺的NEV分别为-17022MJ/t燃料乙醇和-11778MJ/t燃料乙醇,R值分别是0.64和0.72;如考虑副产品能量价值,旧工艺和新工艺的NEV值分别为2271MJ/t燃料乙醇和11249MJ/t燃料乙醇,R值分别是1.05和1.27,从能源经济性角度看,旧工艺和新工艺的能量收益已是正效益,且新工艺的能量收益显著提高;与美国玉米燃料乙醇生产相比,如考虑副产品能量价值,新工艺和美国玉米燃料乙醇的NEV分别为11249MJ/t燃料乙醇和7457MJ/t燃料乙醇,R值分别是1.27和1.34。由于小麦转化率要低于玉米,因而小麦燃料乙醇的R值会低于玉米燃料乙醇。中国小麦燃料乙醇生产(新工艺)NEV大于美国玉米燃料乙醇的原因在于:中国小麦燃料乙醇副产品综合利用水平(23027MJ/t燃料乙醇)已明显优于美国玉米燃料乙醇(5078MJ/t燃料乙醇)。  相似文献   

18.
Energy allocation in polymorphic Brown Trout   总被引:2,自引:0,他引:2  
  相似文献   

19.
能源植物的资源开发与应用   总被引:21,自引:1,他引:20  
随着矿石能源储量的减少,应大力开发和应用以能源植物为主的生物质能。针对在开发和利用能源植物资源过程中遇到的问题,从生物质能角度出发,对能源植物进行了归类,介绍了能源植物的开发历史和国内外利用现状,总结了能源植物的利用方式,分析了我国开发、利用能源植物资源应采取的措施和步骤。  相似文献   

20.
Unsustainable private consumption causes energy and environmental problems. This occurs directly (resource depletion and emissions through using cars for transport) or indirectly (purchase of consumer goods and services for which the production uses energy and emits damaging gases). A hybrid energy analysis proved that indoor energy consumption, mobility, and vacations are the main consumer categories from an energy point of view. Although energy is often used as a proxy for environmental load from private consumption, there are other proxies like methane (CH4), sulfur oxides (SOx), and land use. This article describes the results of the extension of the hybrid energy analysis with energy and ten environmental stressors (CH4, nitrous oxide [N2O], nitrogen, phosphate, SOx, nitrogen oxides [NOx], ammonia [NH3], nonmethane volatile organic compounds [NMVOCs], particulate matter [PM10], and land use), combined in five impact categories (global warming potential [GWP], acidification, eutrophication, summer smog, and land use). Household consumption was analyzed by dividing Dutch household expenditure into 368 consumer items in 11 categories. The results show that food impacts, in particular, are underestimated when only energy is taken into account. Food makes the highest contribution in three out of five impact categories when all ten stressors are taken into account. Within the food domain, meat and dairy consumer items have the highest environmental impact, about 45% of total food impact on average across all five impact categories. Looking in detail (368 consumer items), there are nine food items in the top ten most‐polluting items. Salad oil and cheese are the most polluting food items.  相似文献   

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