设施蔬菜CO2施肥技术研究

对国内外设施栽培蔬菜CO2施肥技术的研究结果进行综述，重点介绍CO1施肥浓度、CO2施肥时间、CO2施肥过程中的环境因子调控、夏季CO2施肥和交替CO2施肥、CO1施肥与NOx污染等。     

北方设施蔬菜生产中CO2施肥效应及研究进展

文章就中国北方设施蔬菜生产中CO2气肥施肥效应、CO2气肥施肥技术以及施肥中注意的问题进行了综述,对北方设施蔬菜生产有一定的指导意义。     

蔬菜CO_2施肥效应与机理研究进展

CO2是光合作用的原料.CO2施肥作为一项增产增效措施在国外设施蔬菜生产中被广泛应用.我国设施栽培大规模发展起步较晚,CO2施肥尚处于生产试验阶段.国内外专家学者围绕CO2施肥的作用机理和应用效果进行了较深入而系统地研究,本文对其研究结果进行综述.     

CO_2施肥对设施花卉生产的影响

该文综述了CO2 施肥对花卉作物生长发育规律和观赏品质的影响 .CO2 施肥可促进花卉作物的生长发育 ,增加切花和插穗产量 ,提高切花和盆花的品质 ,促进扦插生根 ;增强了花卉对不良环境条件的抗性 ,提高了种苗的移栽成活率 .光照强度、光周期、温度、营养供应及植株的发育情况影响了CO2 施肥的效果 ,因此在进行CO2 施肥的同时要相应地改变其他环境条件的设定 ,并合理调整栽培措施 ,才能更大发挥CO2 施肥的作用 .CO2 施肥已经成为提高设施花卉作物产量和品质的理想途径 .     

设施桃树CO2施肥过程中的光合适应现象

以3年生油桃为试材,在山东农业大学现代水暖玻璃温室中进行设施桃树CO2施肥研究.结果表明,在设施桃树CO2施肥过程中存在明显的光合适应现象,在普通空气条件和高浓度CO2条件下均是如此;PS Ⅱ光化学效率的适应可从一个侧面解释桃树CO2施肥过程中的光合适应机制.尽管存在光合适应现象,CO2施肥对桃树的光合作用仍然有着明显的促进作用.     

设施栽培CO2施肥技术

设施栽培增施CO2技术是实现蔬菜高产优质的重要技术措施之一，国外对CO2施肥技术研究较早，应用较普遍，增产效果十分明显。我国自上个世纪70年代后开始对CO2施肥进行研究，并小面积应用，取得了较好的效果。近年来，随着设施栽培面积急剧扩大，国外大型连栋温室与现代化栽培配套技术的引进和消化吸收，设施内CO2施肥作为一项高产、优质、抗病的技术措施，越来越受到园艺工作者和广大菜农的关注。     

CO2施肥对设施油桃生物学特性的影响

以2年生盆栽"曙光"油桃为试材,采用人工加富的方法,研究了CO2施肥对设施油桃生物学特性的影响。结果表明,设施内的CO2浓度远低于露地,CO2施肥后树体的光合速率日变化曲线由3峰变为2峰,第1次高峰比对照推迟约2h,出现在10:00左右,第2次高峰出现在约15:00。经CO2加富处理后,设施内CO2浓度显著提高,新梢速长期处理 , , 的日平均CO2浓度分别比对照高出44.37%,84.31%,119.62%,CO2浓度的提高使得树体的光合速率明显上升。CO2施肥对油桃的新梢、叶片生长发育以及果实的品质有重要影响,3个处理中油桃的平均单果重比对照增加了5.02%,可溶性固形物比对照增加了17.18%,维生素C含量增加了10.48%。同时,新梢长度、叶片面积、叶绿素含量、气孔导度等生理指标也有不同程度的提高。CO2施肥还能降低叶片的光呼吸速率。     

保护地蔬菜CO_2施肥原理与技术

CO2是绿色植物光合作用的主要原料,保护地蔬菜CO2施肥是一项新技术,在国外应用比较普遍,在国内CO2施肥除科研单位和示范园区以外,生产单位还没有普遍使用。该文对保护地蔬菜CO2施肥的原理及施肥方法进行了详细阐述,并提出了施CO2气肥适宜的浓度、施肥时期及CO2施肥应注意的问题,在保护地蔬菜生产上有一定的指导意义。     

增施CO_2对温室草莓生长及光合特性的影响

以甜查理草莓为试材,进行温室草莓CO2施肥研究。结果表明:经CO2加富处理后,设施内CO2浓度显著提高,CO2施肥后株高、株茎、叶面积、叶绿素、叶片鲜重、干重、比叶重都有不同程度的提高。CO2施肥后使草莓叶片的光合速率迅速提高,还降低了气孔导度,减少了蒸腾作用。结论:增施CO2对温室草莓的生长及光合作用有明显的促进作用。     

CO2施肥对黄瓜幼苗根系发育及氮代谢酶活性的影响

以砂培黄瓜为试材,研究了不同CO2施肥处理对幼苗根系生育和氮代谢相关酶活性的影响。结果表明,增加环境CO2浓度和延长CO2施肥时间均明显促进了黄瓜幼苗根系的发育,CO2施肥黄瓜的主根长度、总根长度、根系鲜重、根系分枝、根系活力及其吸收面积均有不同程度的增加;根系硝酸还原酶和谷氨酰胺合成酶活性增强。除氮代谢酶活性外,每天上、下午各以950±50 mmol.L-1CO2施肥3 h的效果大于仅在上午施肥。     

Radiocarbon: analysis of inorganic carbon of fossil bone and enamel

Carbon dioxide from calcium carbonate in fossil bone can be selectively separated from carbon dioxide in bone apatite by hydrolyzing the sample first in acetic acid and then in hydrochloric acid. Radiocarbon analyses of the inorganic carbon dioxide in three samples of known age clearly show calcium carbonate in fossil bone to be secondary and the carbonate of bone apatite to be indigenous and suitable for dating in some cases. Agreement between dates on collagen-bone apatite pairs increases the level of confidence.     

Carbon dioxide sensitivity in mosquitoes infected with sigma, vesicular stomatitis, and other rhabdoviruses

Carbon dioxide, usually an innocuous narcotic for insects, kills mosquitoes infected with rhabdoviruses. Such toxicity was originally observed in Drosophila harboring a hereditary virus, sigma, and has been considered unique to Drosophila. The new findings support the possibility that insects with piercing and sucking mouthparts harbor similar hereditary viruses and transmit some of them to vertebrates or plants.     

Thermal conductivity effect of carrier gases on flame-ionization detector sensitivity

Data for six carrier gases of different thermal conductivities show a linear correlation between the logarithm of thermal conductivity and detector response. Carbon dioxide with a lower thermal conductivity than helium gives a ninefold increase in detector response.     

木材资源利用与气候变化

温室气体的排放使全球气候变暖,从而使自然灾害的频度加大;森林是主要温室气体二氧化碳的吸收源,但只有合理经营,树木年生长量大的森林才能更多地吸收二氧化碳;木材资源的合理利用,有利于提高森林经营的积极性;木材资源利用具有碳贮存效应、省能源效应和能源替代效应,有利于缓和气候变化。     

Net Exchange of CO2 in a Mid-Latitude Forest

The eddy correlation method was used to measure the net ecosystem exchange of carbon dioxide continuously from April 1990 to December 1991 in a deciduous forest in central Massachusetts. The annual net uptake was 3.7 +/- 0.7 metric tons of carbon per hectare per year. Ecosystem respiration, calculated from the relation between nighttime exchange and soil temperature, was 7.4 metric tons of carbon per hectare per year, implying gross ecosystem production of 11.1 metric tons of carbon per hectare per year. The observed rate of accumulation of carbon reflects recovery from agricultural development in the 1800s. Carbon uptake rates were notably larger than those assumed for temperate forests in global carbon studies. Carbon storage in temperate forests can play an important role in determining future concentrations of atmospheric carbon dioxide.     

Ices on the surface of triton

The near-infrared spectrum of Triton reveals ices of nitrogen, methane, carbon monoxide, and carbon dioxide, of which nitrogen is the dominant component. Carbon dioxide ice may be spatially segregated from the other more volatile ices, covering about 10 percent of Triton's surface. The absence of ices of other hydrocarbons and nitriles challenges existing models of methane and nitrogen photochemistry on Triton.     

秸秆生物反应堆对温室黄瓜产量的影响

文章通过对温室黄瓜生长环境及产量的对比分析,发现利用秸秆生物反应堆生产技术,可有效的解决温室内CO2缺乏,显著提高黄瓜产量。     

Oxygen isotope fractionation in the system dolomite-calcite-carbon dioxide

Oxygen isotopes were equilibrated between carbon dioxide and calcite at four temperatures in the range 350 degrees to 610 degrees C and between carbon dioxide and dolomite at 350 degrees and 400 degrees C. Carbon of unusual isotopic composition was used as a tracer to demonstrate the nature and extent of the exchange process. Extrapolation of these data at lower temperatures indicates that at 25 degrees C dolomite is enriched in oxygen-18 by 6.8 per mil with respect to calcite. This result indicates that those natural dolomite-calcite assemblages which show very small fractionations were not formed in isotopic equilibrium.     

高校图书馆“低碳排放”

在低碳时代,在建设资源节约型、环境友好型高校活动中,高校图书馆完全可以从制度层面、管理层面和办公层面为全社会＂低碳排放＂运动作出自己应尽的责任和贡献。     

Carbon in Amazon forests: unexpected seasonal fluxes and disturbance-induced losses

The net ecosystem exchange of carbon dioxide was measured by eddy covariance methods for 3 years in two old-growth forest sites near Santarém, Brazil. Carbon was lost in the wet season and gained in the dry season, which was opposite to the seasonal cycles of both tree growth and model predictions. The 3-year average carbon loss was 1.3 (confidence interval: 0.0 to 2.0) megagrams of carbon per hectare per year. Biometric observations confirmed the net loss but imply that it is a transient effect of recent disturbance superimposed on long-term balance. Given that episodic disturbances are characteristic of old-growth forests, it is likely that carbon sequestration is lower than has been inferred from recent eddy covariance studies at undisturbed sites.