Ambient levels of ozone reduce net photosynthesis in tree and crop species

Experiments were conducted to measure the photosynthetic response of three crop and four tree species to realistic concentrations of ozone and (for tree species only) simulated acidic rain. The ozone concentrations were representative of those found in clean ambient air, in mildly to moderately polluted air such as occurs in much of the United States during the summer, and in more heavily polluted air. However, the highest concentrations of ozone used were lower than those found regularly in the Los Angeles area. The mean pH of the simulated acid rain treatments ranged from more alkaline to much more acidic than the mean pH of precipitation in the United States. Exposure to any increase in ozone reduced net photosynthesis in all species tested. In contrast, acidic rain had no negative effect on photosynthesis in tree species, and no interaction between ozone and acidic rain was observed. Ozone-induced reductions in photosynthesis were related to declines in growth or yield. Species with higher stomatal conductances and thus higher potential for pollutant uptake exhibited greater negative responses to similar ozone treatments. Since exposure to ozone concentrations typical of levels of the pollutant observed in the eastern half of the United States reduced the rates of net photosynthesis of all species tested, reductions in net photosynthesis may be occurring over much of the eastern United States.     

Free Radicals Within the Antarctic Vortex: The Role of CFCs in Antarctic Ozone Loss

How strong is the case linking global release of chlorofluorocarbons to episodic disappearance of ozone from the Antarctic stratosphere each austral spring? Three lines of evidence defining a link are (i) observed containment in the vortex of ClO concentrations two orders of magnitude greater than normal levels; (ii) in situ observations obtained during ten high-altitude aircraft flights into the vortex as the ozone hole was forming that show a decrease in ozone concentrations as ClO concentrations increased; and (iii) a comparison between observed ozone loss rates and those predicted with the use of absolute concentrations of ClO and BrO, the rate-limiting radicals in an array of proposed catalytic cycles. Recent advances in our understanding of the kinetics, photochemistry, and structural details of key intermediates in these catalytic cycles as well as an improved absolute calibration for ClO and BrO concentrations at the temperatures and pressures encountered in the lower antarctic stratosphere have been essential for defining the link.     

Ozone Formation in Air Exposed to Cobalt-60 Gamma Radiation

The amount of ozone formed in air exposed to a 4000-curie cobalt-60 radiation source was determined. In closed glass containers exposed to about I Mrad of gamma radiation, ozone concentrations up to 18 parts per million (by volume) were recorded. In air flowing through a glass structure placed near the source, ozone contents up to 0.1 parts per million were observed. It is suggested that ozone formation might be a factor in the reported germicidal effects of ionizing radiations and that damage to plant tissues, ascribed to radiation, might have resulted from exposure to ozone. The possible health hazards from the ozone produced during irradiation should not be overlooked.     

Stratospheric ozone destruction by man-made chlorofluoromethanes

Calculations indicate that chlorofluoromethanes produced by man can greatly affect the concentrations of stratospheric ozone in future decades. This effect follows the release of chlorine from these compounds in the stratosphere. Present usage levels of chlorofluoromethanes can lead to chlorine-catalyzed ozone destruction rates that will exceed natural sinks of ozone by 1985 or 1990.     

臭氧浓度增加对超级稻南粳9108稻穗不同部位籽粒氨基酸含量的影响

为了解臭氧浓度升高对稻米品质的影响,2015年以高产优质超级粳稻南粳9108为供试材料,利用自然光气体熏蒸平台,设置对照(18 n L·L~(-1))和高浓度臭氧(100 n L·L~(-1))处理,研究了臭氧浓度增加对成熟期稻穗不同部位糙米氨基酸性质的影响。结果表明:臭氧浓度增加使稻米氨基酸、必需和非必需氨基酸总量显著增加,但对必需或非必需氨基酸占氨基酸总量的百分比无显著影响;从氨基酸组分看,除半胱氨酸外,臭氧浓度增加使糙米中7种必需氨基酸和9种非必需氨基酸的含量均呈增加趋势,其中苏氨酸、丝氨酸、谷氨酸、亮氨酸、络氨酸、天冬氨酸和苯丙氨酸的增幅均达显著或极显著水平;总体上,稻穗下部稻米氨基酸及其组分浓度对臭氧浓度增加的响应大于稻穗上、中部,其中臭氧处理与籽粒着生部位对苯丙氨酸、络氨酸、组氨酸、精氨酸有明显的互作效应(P0.1)。以上数据表明,100 n L·L~(-1)臭氧浓度使供试超级稻稻米氨基酸及其组分浓度明显增加,且多数情况下弱势粒的增加趋势大于强势粒。     

Ozone concentrations in new jersey and new york: statistical association with related variables

The concentrations of ozone at nine measurements sites in New Jersey and New York during the period 1 May through 30 September 1973 have been examined. Daily fluctuations in the ozone concentrations at any two sites are highly correlated. The concentrations are lower with low levels of solar radiation and also with high wind speed. The average ozone concentration shows only minor differences between weekdays and weekends, despite markedly different traffic patterns.     

近地层臭氧对农作物产量影响的风险评估模型研究进展

近地层臭氧污染及其对农作物产量和粮食安全的负面效应已成为国内外广泛关注的焦点之一,建立适宜且更为精确的模型开展臭氧影响下的农作物产量损失评估对于粮食安全保障及臭氧污染控制具有重要的意义。综述了浓度响应、剂量响应和通量响应等统计模型的发展及其在产量损失评估中的应用,评述了其优缺点和通量响应模型的不确定性,同时,通过臭氧干沉降模型的研究进展及其与通量响应模型的优势比较,提出了基于观测和臭氧干沉降模型开展臭氧影响下的自然农田作物产量损失评估技术新的研究方向。     

臭氧浓度增加对不同敏感型水稻元素吸收与分配的影响

利用新型自然光气体熏蒸平台,以23个水稻品种或株系为供试材料,设置室内对照(10.4 n L·L-1)和臭氧浓度增高(100 n L·L-1)处理,采用组内最小平方和的动态聚类方法,将供试材料按地上部最终生物量对臭氧胁迫的响应从小到大依次分为A、B和C类,研究不同敏感类型水稻营养器官中元素浓度、吸收与分配对臭氧胁迫的响应。臭氧熏蒸使A、B和C三类水稻地上部生物量平均分别下降19%、39%和52%,后两者达极显著水平。与对照相比,臭氧胁迫使稻草中N、P、K、Mg、Mn、Fe、Cu和Zn浓度显著或极显著增加(5%~42%),但对Ca浓度没有影响。与此相反,臭氧熏蒸使稻草中所有测定元素的吸收总量均呈下降趋势,其中N、P、K、Ca、Mg、Cu、Fe和Zn吸收量的降幅均达极显著水平(11%~34%)。多数情形下,茎鞘各元素浓度和吸收量对臭氧胁迫的响应大于叶片。与此相对应,臭氧胁迫使水稻吸收的元素向叶片中分配的比例增加,而向茎鞘分配的比例减少,导致叶片与茎鞘元素吸收量的比值大幅增加(32%~92%)。臭氧与水稻类型的互作对营养器官各元素浓度以及元素在茎叶中的分配比例多无显著影响,但对元素吸收量的影响多达显著或极显著水平,后者表现为臭氧胁迫下敏感水稻元素吸收的受抑程度更大。研究结果表明,与干净空气相比,100 n L·L-1臭氧浓度对水稻营养器官中各元素浓度、吸收和分配多有显著影响,其中元素吸收量对臭氧胁迫的响应明显受水稻敏感程度的影响。     

Atmospheric Trends and Lifetime of CH3CCI3 and Global OH Concentrations

Determination of the atmospheric concentrations and lifetime of trichloroethane (CH(3)CCI(3)) is very important in the context of global change. This halocarbon is involved in depletion of ozone, and the hydroxyl radical (OH) concentrations determined from its lifetime provide estimates of the lifetimes of most other hydrogen-containing gases involved in the ozone layer and climate. Global measurements of trichloroethane indicate rising concentrations before and declining concentrations after late 1991. The lifetime of CH(3)CCI(3) in the total atmosphere is 4.8 +/- 0.3 years, which is substantially lower than previously estimated. The deduced hydroxyl radical concentration, which measures the atmosphere's oxidizing capability, shows little change from 1978 to 1994.     

臭氧浓度升高和叶面施锌对小麦籽粒产量、锌浓度及有效性的影响

研究臭氧浓度升高和叶面施锌对小麦产量和籽粒不同组分锌营养的影响,为气候变化背景下小麦的锌生物强化提供理论依据和技术参考。利用自然光气体熏蒸平台,以富锌小麦品种青紫1号为供试材料,臭氧处理设清洁空气和臭氧浓度升高(100nL·L-1,拔节至收获),锌处理设对照(喷清水)和叶面施锌(开花期及花后1周叶面喷施0.1%Zn2+),成熟期测定小麦产量及其构成因素、籽粒各组分的锌浓度、锌含量、植酸浓度以及植酸与锌的摩尔比。叶面施锌处理对小麦籽粒产量没有影响,但臭氧浓度升高使产量平均下降66%。臭氧胁迫导致的产量损失主要与粒重明显减轻(53%)有关,其次亦与每穗粒数减少(27%)有关,而穗数没有变化。麦粒各组分锌浓度、植酸浓度以及植酸与锌摩尔比均表现为麸皮次粉面粉。与清洁空气相比,臭氧浓度升高使籽粒各组分的锌浓度和植酸浓度均明显增加,分别增加15%～41%和8%～45%,各组分植酸与锌摩尔比无显著变化;臭氧浓度升高使小麦面粉锌累积量占籽粒总锌的百分比显著减少。与对照相比,叶面施锌使小麦各组分锌浓度平均增加22%～24%,使植酸与锌摩尔比平均减少15%～19%,但籽粒各组分植酸浓度以及锌在各组分的分配比例均无显著影响。臭氧与锌处理对所有测定参数均无交互作用,但这两个处理与籽粒组分之间多存在不同程度的互作效应。臭氧胁迫环境下青紫1号籽粒产量和锌累积量大幅下降,籽粒各组分锌浓度显著增加,但生物有效性没有变化;花后叶面施锌对小麦产量没有影响,但使籽粒不同组分锌的营养水平均明显增加,且增幅不受臭氧浓度升高的影响。     

Influence of surface ozone on crop yield of maize in China

This study investigated the adverse effect of surface ozone on the maize yield using a unique panel from 880 counties in China. To identify the impact of elevated surface ozone concentrations, we constructed an econometric model by controlling the impact of climate variables and related economic variables. This study also considered the potential spatial correlation in the measurement of the impact of surface ozone on maize yield. Results confirmed that the increase of ozone concentration decreased the maize yield. Moreover, maize was found to be the most sensitive to ozone at the end of the second month of the growing season. The average annual loss of maize caused by ozone pollution is about 4.234 million tons in 2013–2015, accounting for 1.9% of the average output.     

臭氧水去除大白菜中百菌清残留的研究

为了研究大白菜中百菌清残留经臭氧水处理后的去除效果,采用臭氧质量浓度不同和同一臭氧质量浓度浸泡时间不同处理,利用乙腈溶剂提取,固相萃取净化,毛细管柱气相色谱法分离。GC-ECD进行定性定量分析。结果显示,通入臭氧10,15,30和40min制备臭氧水质量浓度为0.99,3.48,5.26和5.64mg/L,百菌清去除率分别为14.7%,90.5%,96.7%和97.5%;说明随着臭氧水质量浓度增大,百菌清残留去除效果越好。当臭氧水质量浓度(5.2~5.3mg/L)一定时,随着浸泡时间延长,百菌清残留去除效果增加;臭氧水浸泡大白菜15min和30min,百菌清残留去除率分别为83.8%,98.3%,同样的时间以自来水做对照组浸泡,百菌清去除率分别为6.9%,18.3%,说明臭氧水去除百菌清农药的效果显著。     

臭氧对青菜中3种有机磷农药去除效果及Vc和类胡萝卜素含量的影响

为综合评价臭氧在蔬菜产后处理中降低有机磷农药残留的作用及其对蔬菜营养成分的影响,分别 采用不同浓度臭氧水和水中持续通臭氧浸泡两种处理方式,模拟测定臭氧对青菜中有机磷农药残留的去除效果, 及臭氧处理对青菜中Vc、类胡萝卜素含量的影响。结果表明,臭氧可加快去除水浸泡处理青菜中的残留农药,且以 水中持续通臭氧处理效果更佳;青菜中残留农药敌敌畏、乐果和毒死蜱的浓度分别为11．22,6．31和7．04 mg／kg 时,以0．119 mol／L NaHCO3水溶液浸泡,并持续通臭氧处理30 min,去除率分别为79．32％,63．26％和65．54％; 臭氧水处理对青菜中Vc含量基本没有影响,但明显降低类胡萝卜素含量。     

臭氧水对生姜根结线虫的防治及产量与品质的影响

[目的]探讨臭氧水对生姜根结线虫的防治效果及对生姜生长、产量和品质的影响。[方法]利用WF-60型根治根结线虫专用机产生不同浓度臭氧水,通过用不同浓度臭氧水灌溉生姜研究了臭氧水对生姜根结线虫的防治效果及对大姜生长、产量和品质的影响。[结果]6 mg/kg臭氧水对生姜根结线虫病的防治效果达93.3%,同时对生姜的产量和品质均有较大提高。[结论]为建立环保高效的根结线虫防治方法提供了借鉴。     

Impact of polar ozone depletion on subtropical precipitation

Over the past half-century, the ozone hole has caused a poleward shift of the extratropical westerly jet in the Southern Hemisphere. Here, we argue that these extratropical circulation changes, resulting from ozone depletion, have substantially contributed to subtropical precipitation changes. Specifically, we show that precipitation in the southern subtropics in austral summer increases significantly when climate models are integrated with reduced polar ozone concentrations. Furthermore, the observed patterns of subtropical precipitation change, from 1979 to 2000, are very similar to those in our model integrations, where ozone depletion alone is prescribed. In both climate models and observations, the subtropical moistening is linked to a poleward shift of the extratropical westerly jet. Our results highlight the importance of polar regions for the subtropical hydrological cycle.     

Ozone loss inside the northern polar vortex during the 1991-1992 winter

Measurements made in the outer ring of the northern polar vortex from October 1991 through March 1992 reveal an altitude-dependent change in ozone, with a decrease at the bottom of the vortex and a substantial increase at the highest altitudes accessible to measurement. The increase is the result of ozone-rich air entering the vortex, and the decrease reflects ozone loss accumulated after the descent of the air through high concentrations of reactive chlorine. The depleted air that is released out of the bottom of the vortex is sufficient to significantly reduce column ozone at mid-latitudes.     

臭氧对离体华支睾虫囊蚴生命力的影响

【目的】研究臭氧对离体华支睾虫囊蚴的杀灭作用,为探索一种既能杀灭寄生虫囊蚴又能保持肉品生鲜的方法提供参考依据。【方法】对采自广西横县横州镇上淇铺岭村河流的麦穗鱼和银飘鱼进行华支睾虫囊蚴压片镜检,以囊蚴阳性鱼为试材,采用人工胃液消化法从感染鱼中获取囊蚴;然后将囊蚴按50个/组分为若干组置于蒸馏水中,比较臭氧通入方式、时间及初始浓度对离体囊蚴的影响。【结果】在蒸馏水中通入臭氧均为10 min时,先通臭氧再放入囊蚴的囊蚴死亡率显著低于先放囊蚴后通臭氧。在先放囊蚴后通臭氧的处理方式下,随着臭氧通入时间延长,囊蚴死亡率明显提高;通臭氧10 min,囊蚴死亡率高于70.00%,且剩余未脱囊囊蚴中的后尾蚴已基本丧失活动力;当通臭氧20 min,囊蚴死亡率达到100.00%,后尾蚴全部停止活动。在密闭条件下,蒸馏水中臭氧初始浓度越高,囊蚴死亡率越高。华支睾虫囊蚴在臭氧水中的活动表现为：臭氧通入前期,后尾蚴活动剧烈欲冲破囊壁;随着时间延长,部分后尾蚴冲破囊壁脱囊而出,最后后尾蚴活动减慢直至死亡。【结论】臭氧处理对于杀灭离体华支睾虫囊蚴效果显著,其效果和程度与臭氧的处理方式、接触时间、浓度密切相关。     

Ozone in High Concentrations as Cause of Tobacco Leaf Injury

Evidence obtained by means of rubber strip tests and an ozone recorder indicates the presence of abnormal concentrations of ozone in the atmosphere at times. Excellent correlation was obtained between appearance of "weather fleck" in tobacco and high values for ozone. The great similarity between lesions occurring naturally and those produced by ozone in chambers also indicates that ozone is the probable inciting agent of weather fleck. Varietal differences exist. Study of stomatal action helped to explain variation in leaf injury.     

不同浓度臭氧水对致病疫霉菌Phytophthora infestans孢子萌发抑制作用初报

本文采用不同浓度臭氧水对致病疫霉菌Phytophthora infestans (Mont.) de Bary孢子囊萌发进行了试验，结果表明：臭氧水处理对孢子囊萌发的影响与臭氧水浓度密切相关，以9 mg/Kg臭氧水处理1 min可以抑制95%以上孢子囊萌发，以18 mg/Kg臭氧水处理1 min则100%抑制孢子囊萌发。无论在高浓度还是在低浓度条件下，处理时间1分钟或2分钟对孢子囊萌发没有产生显著影响，杀菌作用几乎是瞬间完成的。臭氧水处理孢子囊后导致孢子囊形态发生变化，这种变化随时间延长变得更加明显。鉴于高浓度臭氧水对植物本身不产生毒害作用，因此，高浓度臭氧水在控制晚疫病方面显示出广阔的应用前景。     

Ozone and sulfur dioxide synergism: injury to tobacco plants

Tobacco plants displayed ozone-type injury when exposed to mixtures of ozone and sulfur dioxide at subthreshold concentrations. The syndrome suggests synergism between ozone and sulfur dioxide that lowers thresholds to injury; exposure to the individual gases at the mixed-gas concentrations caused no symptoms.