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1.
刘迪林  蔡杰 《农业工程学报》2005,21(14):221-224
该文综合分析国内外有关近地面臭氧伤害作物,臭氧污染呈上升趋势的资料,以及对温室臭氧状况做尝试性监测后认为,因光化学反应,温室环境会存在臭氧污染,其浓度有可能达到伤害作物的程度。温室臭氧规律有待深入调查。温室中使用臭氧气体防治病虫害是个错误。  相似文献   

2.
臭氧含量增加有害健康英国的专家4月19日警告说,污染引起地球表面臭氧含量不断增加会给人类健康、作物、植物以及建筑物等造成威胁。英国的光化学氧化物检查团体(PORG)说,英国和其它欧洲共同体国家虽已制定了控制污染的措施,但是,它并不能达到2000年对臭...  相似文献   

3.
温室作物模型与环境控制管理研究   总被引:13,自引:2,他引:13       下载免费PDF全文
阐述了国内外作物模型研究现状 ,温室园艺作物模型研究进展以及温室作物模型在现代化农业环境控制管理中的重要作用 ,并简介了温室番茄作物模拟系统研制开发现状及其进展  相似文献   

4.
中国北方典型地区农用地膜污染现状调查及其防治对策   总被引:10,自引:0,他引:10  
通过对我国北方典型地区的调查,初步探索了该地区土壤农膜残留量和残膜特征.研究表明,河北省典型地区温室大棚、蔬菜田和作物田的农膜土壤残留量平均分别为5.629、7.369和2.822 kg·hm-2,黑龙江省典型地区温室大棚、蔬菜田和作物田残留量平均分别为4.169、3.682和2.430 kg·hm-2,各采样点之间存在着较大差异,但普遍较高,均明显高于未使用农膜的对照土壤.两地区之间除作物田的土壤农膜残留量没有明显差异外,河北地区其他两类土壤中的农膜残留量水平明显高于黑龙江地区,这种差异与各地区在农事活动及农膜使用上的差异具有一定的相关性.上述两地区土壤中残留农膜尺寸基本一致,主要集中在10~15 cm之间.该文针对我国目前农膜使用情况及其污染现状,提出了相应的防治对策.  相似文献   

5.
徐亚玲 《南方农业》2008,2(3):39-42
温室生态系统是人为创造的适合作物生长的独特生态环境.这种人为环境条件同时适于病原微生物的生长危害,因而温室内病害的发生往往较露地更为严重.根据都匀地区温室生态系统中蔬菜病害的调查,分析发病原因,从而制定温室蔬菜病害无公害防控技术.  相似文献   

6.
基于作物响应的温室环境SVMR控制仿真   总被引:2,自引:2,他引:0  
在温室环境控制中,传统的根据专家经验的设定值确定控制的目标,由于经验的局限性和作物生长的适应性等原因而不能准确确定设定值,影响温室生产的效率。该文采用仿真模型,研究根据作物响应自动确定控制目标的温室环境控制方法。根据作物生长模型和温室环境变化模型采用遗传算法自动确定温室环境的设定值,采用稳定性、鲁棒性好的OS-LSSVMR(在线稀疏最小二乘支持向量机回归)内模控制进行温室环境控制。通过仿真,在相同室外条件下,基于作物响应的温室环境控制方法消耗的能量更少,作物的干质量增加的更多,控制的精度更高。说明了该方法  相似文献   

7.
在北京大兴区选择一普通温室大棚,观测正常管理方式下黄瓜生长期(2012年10月12日-2013年4月26日)温室大棚内的空气温、湿度数据,根据病菌侵染适宜的空气温度、相对湿度和叶片湿润时间,分析作物潜在病害的发生概率.结果表明,88.1%的潜在病害发生在凌晨和夜间,加强凌晨和夜间时段的温室管理是减少温室大棚病害发生的关键;潜在病害发生天数占观测周期内总天数的22.8%,2-4月潜在病害发生概率占全生育期的97.7%,其中3月最严重,占总量的53.3%,3月份温室大棚作物的食品安全潜在风险可能最大.研究结果可为北京地区温室大棚作物病害的管理提供科学依据.  相似文献   

8.
张琪  彭小燕  顾沛澍  缪明榕  丁峥臻 《土壤》2022,54(2):415-423
本文通过分析地处长江口北岸的南通市2014—2017年臭氧污染变化特征和气象要素以及天气形势对臭氧质量浓度的影响,归纳了高浓度臭氧出现的天气形势,使用多元逐步回归建立了不同月份臭氧质量浓度预报模型.结果表明:春、夏季臭氧质量浓度较高,冬季最小;2014—2017年臭氧超标日数呈明显增加的趋势,臭氧超标日主要出现在4—1...  相似文献   

9.
温室作物生态健康智能监护系统(GH-Healthex)的研制与测试   总被引:2,自引:0,他引:2  
研制温室作物生态健康智能监护系统是为了解决目前温室环境监控系统普遍存在的自动获取的数据未与具体作物健康生育的特殊需求相结合,也未被用于病虫害的智能化防治等问题。该文报导的温室作物生态健康智能监护系统(GH-Healthex)实现了这类数据在植物健康监护和病虫害智能化防治中的利用。以番茄为研究案例,系统通过对温室环境监测数据的分析,结合作物种植知识库中番茄生长发育及其病虫害发生规律可以进行智能化决策,即当温室内出现了不利于作物生长的气象条件时,系统会自动的通过系统界面提示用户采取相应措施,以保证温室番茄的优质、高效生产。该系统提供了一个作物知识库平台,若以其他作物的种植和病虫害防治数据替代番茄数据,便能更广泛地推广应用。  相似文献   

10.
基于模型的温室加温控制目标优化系统研究   总被引:7,自引:5,他引:7  
温室加温控制目标的设定合理与否,直接影响温室作物生长及温室环境调控的能耗。本研究以温室作物生长模拟模型和温室加温能耗预测模型为基础,建立了基于模型的温室加温控制目标计算机优化系统。系统包括一个数据库(温室、作物以及气象资料)和三个模型(作物生长模拟模型、温室加温能耗预测模型以及加温控制目标优化模型)。系统的输入主要为温室类型、温室结构、覆盖材料、作物信息以及室外气象资料,系统输出主要为作物干物质生产量、温室加温能耗量以及干物质生产能耗量利用效率最高和生物量最高的温室白天和夜间的加温控制目标(温度设置点)。以2003年1月20日~2月20日上海孙桥现代农业开发区Venlo型自控玻璃温室水果型黄瓜生产为实例进行分析,结果表明,在上海地区冬季进行温室水果型黄瓜生产时,在开花至果实采收初期将白天和夜间加温控制目标分别设为23℃和17℃时可以获得最高的干物质生产量;将白天和夜间的温室加温的温度分别设为20℃和15℃能够使黄瓜干物质生产的能耗量利用效率达最大,并能够使黄瓜干物质产量也处于较高的水平。本研究建立的基于模型的温室加温控制目标优化系统为中国温室气候控制中温度的优化调控提供了理论依据和决策支持。  相似文献   

11.
The experiments of the United Nations/Economic Commission for Europe (UN/ECE) International Cooperative Programme on effects of air pollution and other stresses on crops and non-wood plants (ICP-Crops) are designed to investigate the effects of ambient ozone pollution on crops and non-wood plants. Each year, participants from approximately 17 European countries conduct a series of coordinated experiments to determine which species develop visible injury following ozone episodes and whether the biomass or yield of sensitive species is reduced. In 1993, ozone injury was only seen at two thirds of sites but in 1994 injury was detected at almost all sites. This coincides with generally higher ozone concentrations measured in that year. Injury was seen on crops including subterranean clover (Trifolium subterraneum L.), white clover (Trifolium repens L.), bean (Phaseolus vulgaris L.), tomato (Lycopersicon esculentum), soybean (Glycine max), watermelon (Citrullus lanatus) and tobacco (Nicotiana tabacum L.) at experimental sites and in some cases, in commercial fields. The application of ethylenediurea (EDU) to some crop species reduced the level of visible injury. At some sites, the yield of EDU-treated bean plants was greater than that of untreated plants where the critical level of ozone for yield reduction was exceeded. Preliminary analysis of ozone concentrations in the days preceding injury indicated a sequential ozone concentration effect. The results are discussed in relation to Level I and Level II mapping of exceedance of the short- and long-term critical levels for ozone.  相似文献   

12.
In recent decades, ambient gaseous pollution has increased due to anthropogenic activities worldwide. The studies to evaluate the adverse effects of ambient pollutants on commonly grown food crops are still limited, especially in Asian countries like Pakistan. The present study was conducted to measure the ambient pollutants in different sites of Faisalabad and their impact on growth and yield of wheat, mung bean and peas. Plants were grown in pots and placed at three sites named as control (Wire house of Government College University, Faisalabad), low pollution (LP) (Farm Area of Ayub Agricultural Research Institute) and high pollution (HP) (GT Chowk, Faisalabad) sites. Results showed that ambient ozone (O3) concentration was highest at HP site followed by LP site and was below AOT40 in control site. Ambient pollutants caused foliar injury in crops and decreased plant height, leaf area, biomass and grain yield. Pollutants caused a reduction in photosynthetic pigments, stomatal conductance and net photosynthetic rate and grain protein contents in all three crops. In conclusion, the ambient O3 level was highest at HP site, this current O3 level and other pollutants decreased the growth and yield of important food crops.  相似文献   

13.
近地层臭氧浓度增高对稻米品质的影响: FACE研究   总被引:1,自引:0,他引:1  
利用稻田开放式空气中臭氧浓度增加(FACE,Free Air gas Concentration Enrichment)平台,以常规粳稻‘武粳15’和杂交粳稻‘陵风优18’为供试材料,设置大气背景臭氧浓度(Ambient)和高臭氧浓度(比Ambient增高21%,模拟21世纪中叶臭氧浓度)两个水平,研究臭氧胁迫对大田生长水稻成熟期稻米加工、外观、蒸煮/食味和营养品质的影响及其种间差异。结果表明,近地层臭氧浓度增高使稻米糙米率、精米率和整精米率均不同程度下降,其中精米率降幅达显著水平。与Ambient相比,臭氧胁迫使两品种稻米垩白米率、垩白大小和垩白度平均分别增加15.0%(P=0.10)、42.0%(P0.05)和60.5%(P0.05)。臭氧胁迫使稻米胶稠度平均降低7.1%(P0.05),但对两品种稻米直链淀粉和糊化温度均无显著影响。稻米RVA谱测定结果显示,臭氧胁迫对稻米最高黏度值、崩解值、冷胶黏度值、消减值和回复值均无显著影响。臭氧胁迫使两品种稻米蛋白质浓度呈增加趋势,但均未达显著水平。方差分析表明,多数情况下,两品种间稻米诸品质性状存在显著差异,但品种与臭氧的互作对所有测定指标均无显著影响,说明两品种稻米品质对臭氧胁迫的响应无明显差异。本试验在开放稻田条件下运行,适度臭氧胁迫使稻米垩白明显增加,胶稠度显著下降,但对其他米质指标影响较小,两品种趋势一致。  相似文献   

14.
温度对不同年限日光温室土壤氮素矿化特性的影响   总被引:3,自引:0,他引:3  
【目的】日光温室作为具有我国特色的一种高强度的栽培方式,过量施肥问题突出。随着温室栽培在我国北方地区规模的不断扩大,由此带来的土壤退化和地下水污染问题值得关注。不少研究表明,随着日光温室栽培年限的增加,土壤有机质含量不断增加;且温室栽培中的土壤温度与露地存在很大差异,其土壤氮素矿化特性如何,尚缺乏研究。【方法】本研究以位于黄土高原南部陕西省杨凌示范区不同栽培年限的日光温室土壤为研究对象,采用室内好气培养法(84 d)测定不同培养温度(20℃和30℃)对不同年限温室(0 3年)土壤0—20 cm及20—40cm土层氮素矿化量,采用一级动力学方程拟合土壤氮素矿化曲线,根据土壤氮矿化势(N0)评价不同栽培年限温室土壤氮素矿化特性。【结果】1)随着日光温室栽培年限的增加,土壤有机质、全氮含量和氮素累积矿化量随之显著增加。2)30℃的土壤氮素累积矿化量高于20℃的矿化累积量;栽培年限长的日光温室矿化作用对温度的敏感程度高于年限短的温室。3)若温度和栽培年限同时增加,土壤氮素累积矿化量随之增加,说明温度和栽培年限对土壤氮素净矿化量有一定的交互作用,但差异不显著(P0.05)。4)日光温室栽培年限越长,土壤氮矿化势(N0)越大;与种植前相比,第2a、3a温室土壤氮矿化势增加了5.59和11.48倍。5)回归分析表明,0—20 cm土层土壤有机质含量每增加1 g/kg,20℃和30℃条件下土壤氮矿化势(No)分别增加2.70及3.18 mg/kg;土壤全氮含量每增加1g/kg,No分别增加37.28及43.12 mg/kg。【结论】日光温室土壤氮素矿化量随其栽培年限的增加显著增加;培养温度由20℃增加到30℃,土壤氮素矿化量也明显增加,日光温室栽培年限和温度对土壤氮矿化有一定的正交互效应。因此,在日光温室氮素管理中应考虑栽培年限和温度对土壤氮素矿化的影响,以采取针对性的氮素管理措施。  相似文献   

15.
This study presents the first experimental evidence of the sensitivity of rice plants to ambient air pollution from the Southeast Asian tropical region. Two widely adopted local cultivars of rice (Oryza sativa L.), MR84 and MR185, were grown in open top chambers ventilated with charcoal-filtered air and non filtered air, and in adjacent open plots on the campus of University Putra Malaysia. This is located on the south side of the Klang Valley, a rapidly developing area embracing Kuala Lumpur and other satellite cities, but where agriculture remains important The experimental period was from October 2000 to January 2001, corresponding to the main rice growing season in peninsular Malaysia. Adverse impacts on rice growth and yield were observed and were attributed to phytotoxic levels of ambient ozone. There was a clear difference in the sensitivity of the two selected cultivars. A yield reduction of 6.3% was observed for cultivar MR185 (p < 0.01) which was largely due to an increase in grain sterility, whilst the yield reduction for cultivar MR84 was not statistically significant. The reasons for these differing responses are discussed, and a comparison of the present findings with crop responses to ozone found under European conditions suggests a higher sensitivity in our study crops. With increasing industrialisation and urbanisation, this study highlights the need for further examination of the sensitivity of a wider range of crops and cultivars to ambient air pollution in this region, and also points to the potential for appropriate cultivar selection to ameliorate impacts.  相似文献   

16.
Critical levels of tropospheric ozone, established for the protection of crops and other plants, are now reported as being exceeded over large forested areas, giving rise to the need for an extensive monitoring program to confirm ambient levels within the forest and to detect related forest health effects. The requirement for an inexpensive monitor that can be used in remote locations prompted the development of the Can Oxy PlateTM passive ozone monitor and a monitoring protocol by the air pollution research group of the Canadian Forest Service, Forest Health Network. The monitors underwent initial trials in 1996 and operational trials during 1997 that involved two 2-3 week mid summer exposures in the canopy at selected forest health monitoring plots across Canada, and at adjacent forest openings. In both trials monitors were also co-located with the nearest instrumental ozone monitor. This allowed for the production of a field calibration for quality assurance assessment under field conditions. Results from 1996 indicate highly significant correlations with accumulated ambient ozone concentrations from the instrumental monitors at the co-located sites (r=0.88, p=0.0002). However, no such relationship was found between these sites and the forest plots which were up to 200 kilometres away. This may indicate spatial heterogeneity in ozone exposure between the continuous air quality monitoring sites and the forest plots. This information, together with our knowledge that strong gradients of ozone exposure are found within the canopy, underlines the importance of in situ monitoring of ozone exposure of forest health plots at risk to ozone effects.  相似文献   

17.
In recent years, international air pollution effects research has focused on setting critical levels of pollutants, above which adverse effects occur on sensitive receptors. Once established, these levels are used to determine the geographical extent of exceedance for different vegetation categories and ultimately in the development of international protocols for pollution control within the Convention on Long-range Transboundary Air Pollution. Ideally, the critical level for each pollutant and vegetation category should have a relatively simple definition to allow ease of mapping. Nevertheless, the definitions need to be sufficiently robust to apply to sensitive vegetation growing in a diverse range of climates. The restrictions imposed by these criteria have led to complex and delicate negotiations between scientists from the UN/ECE* region. Data for the direct effects of air pollutants on vegetation have been carefully reviewed for applicability to critical levels. To date, critical levels have been set for the effects of SO2, ozone, NOx and NH3 on crops, trees and natural vegetation. The use of effects data to establish these levels is critically assessed in this paper in relation to current and future requirements for mapping.  相似文献   

18.
Open top chambers (OTCs) are useful tools to assess the impact of atmospheric pollutants on plants in the natural environment. We have previously reported that, in tomato plants, the LTR-GUS construct derived from the Tnt1A promoter of tobacco was activated by a realistic level of ozone pollution. In this study, we used OTCs to fumigate tomato plants with benzene or formaldehyde in order to assess the impact of these pollutants on plant growth and development and evaluate the usefulness of the LTR-GUS construct as a biomarker in plants. Whereas the LTR-GUS construct could be used as an efficient biomarker of realistic levels of ozone pollution, it is to a lesser extent applicable to formaldehyde. Indeed, only unrealistic concentration of pollutant activated the construct though important injuries were observed at a lower concentration. For benzene, no activation could be demonstrated, however, we did not notice any visual impact on plant growth and health for this pollutant.  相似文献   

19.
In Britain wheat is an important crop accounting for 41% of the total cereal production. In this study ozone concentrations for 1989 estimated as described in Part 1 of the paper are integrated with the estimated wheat distribution to derive a detailed estimate of the impact of ozone on wheat yields at a fine spatial scale (1km × 1km). These data provide estimates for calculating regional and national yield losses. The methodology can be applied to other crop species. Recent research on a range of crops has established relationships between the economic yield loss for certain crops, including wheat, and ozone exposure. Exposure is described as the accumulated exposure above a threshold experienced during the daylight hours (AOT). Critical AOT values are derived from yield exposure relationships which show linear reductions of yield loss with increasing ozone concentrations. This study has made use of land cover data from remotely sensed imagery at 25m resolution and nationally collected agricultural statistics for counties. These data were combined using an areal interpolation technique to provide more spatially articulate estimates of the location and intensity of wheat production. The results demonstrate the economic importance of ozone as a pollutant. Wheat yield losses attributed to ozone vary between different parts of the country but, for years when ozone levels are high, yield losses are likely to be significant in some areas.  相似文献   

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