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近地层O3和CO2浓度变化对冬小麦影响的数值模拟：Ⅱ模拟结果和分析 总被引：4，自引：2，他引：4
针对CO2和O3浓度变化对冬小麦影响,改进了农田生态系统碳氮生物化学模型(DNDC),并利用模型模拟了O3和CO2浓度变化对冬小麦生长发育和产量的影响,检验了模型的模拟效果.通过对原DNDC模型适用性的调整,使之适用于固城站,为进一步改进作物模型打下了可靠的基础.通过试验资料验证表明,模型较好地反映了O3和CO2浓度变化对冬小麦生长发育和产量形成的影响.通过敏感性分析得出,模型对温度变化反映灵敏;在CO2浓度倍增情况下,O3浓度变化对冬小麦的复合影响分析看出,一定浓度范围内,CO2可缓解O3对作物影响的负效应,O3对CO2带来的正效应有削弱作用. 相似文献
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以大豆“中黄-14”为试验材料, 利用OTC-1型农田开顶式气室, 首次模拟研究单独CO2和O3浓度倍增及其交互作用对大豆生物量、产量及其构成因子、同化产物分配形式和收获指数的影响。与未通CO2和O3的处理相比, 单独CO2浓度倍增对生物量、产量、荚果串数、荚数、籽粒数、籽粒重具有正效应, O3为明显的负效应, 通气时段越长效果越明显; 持续的CO2浓度和O3浓度倍增交互作用表现为CO2的影响大于O3; CO2和O3交互作用逐渐达到浓度倍增的处理, 由于O3剂量逐渐累积和阶段性增加, 对大豆刺激逐渐增强, 最终O3的负效应与CO2的正效应相近。单独O3浓度倍增抑制光合产物向根和籽粒的输送, 向叶茎的输送明显增强, 使根冠比 (RSR)、子粒与茎杆比 (GCR) 明显下降, 长期作用可使大豆收获指数 (HI) 减小, 叶重比 (LWR) 显著增加, 且随通气时间的延长影响增大; CO2浓度倍增及其交互作用对RSR、LWR、GCR和HI影响相对较小, 仅在±10%左右。 相似文献
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大气中O3和CO2增加对大豆复合影响的试验研究 总被引：1，自引：0，他引：1
利用OTC-1型开顶式气室,对大豆"中黄14"进行了长时期不同O3和CO2处理的接触试验,模拟研究CO2和O3浓度倍增及其交互作用对大豆发育期、黄叶率和绿叶率、根瘤、生物量及其分配、产量结构、籽粒品质及叶片膜保护系统的影响,结果表明:单独O3浓度倍增,发育期明显提前;生物量最多可减少近一半,产量最多减产60%以上;粗蛋白含量增加6.2%,粗脂肪含量降低7.6%;叶片脂膜过氧化加剧.单独CO2浓度倍增,开花后发育期有所延迟;对生物量及产量有明显的正效应,成熟时总生物量和籽粒产量分别比T5增加21.0%和20.3%;粗蛋白和粗脂肪含量分别下降3.3%和1.6%;结荚前叶片脂膜过氧化反应减轻.CO2和O3持续倍增和逐渐达到倍增交互作用处理,在生物量、产量方面表现为CO2的影响大于O3,在叶片膜保护系统方面表现为O3的影响大于CO2,粗蛋白含量下降,粗脂肪含量上升,叶片脂质过氧化加剧.熏气处理均可造成:黄叶率上升,绿叶率下降,凋落物增加,且单独O3浓度倍增的处理最明显,通气仅10天黄叶率就高于50%;超氧化物歧化酶活性增强;气孔阻力增加,蒸腾速率下降,且单独CO2浓度倍增的处理最明显,尤其在高湿阴天,气孔阻力和蒸腾速率变化最高分别可达增加234.0%和下降58.5%. 相似文献
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在试验研究的基础上,文中尝试利用数值模拟方法评估O3和CO2浓度变化对作物的影响.以农田生态系统碳氮生物化学模型(DNDC)为基础,对其中的作物子模型进行改进,加入O3对冬小麦光合作用和叶片生长影响的模拟,结合原模型中有关CO2对冬小麦光合作用影响的模拟,建立反映O3和CO2浓度变化对冬小麦生长发育和产量形成影响的作物模型.文章对DNDC模型进行了参数修正以适用于中国华北地区;文章参考前人的工作,引用了两种O3对作物光合作用影响的模拟方法进行比较,分别是O3对初始光利用率的影响和O3对叶片光合作用的直接影响;在此基础上,进一步考虑O3对冬小麦叶片生长的影响,根据试验资料,建立了O3对叶片生长影响系数. 相似文献
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O3,CO2浓度及太阳光谱变化对作物光合作用影响的数值模拟研究 总被引：4，自引：2，他引：4
对光合作用 蒸腾作用 气孔调节进行耦合 ,从生物化学尺度扩展至冠层尺度 ,发展了一个冬小麦冠层光合作用生态动力模式 ,模式考虑了O3,CO2 和光谱变化对作物光合的综合影响。利用美国光合作用实测资料对模式进行验证 ,叶片模式通过了相关显著性检验并具有较高的准确度。数值分析表明 :当O3 浓度由 0× 10 -9V/V上升至2 0 0× 10 -9V/V时 ,冠层光合速率下降 2 9%左右 ;当CO2 浓度由 330× 10 -6V/V上升至 6 6 0× 10 -6V/V时 ,冠层光合速率增加大约 37% ;当光谱比例系数由目前的 0 .5下降至 0 .4时 ,冠层光合速率将下降 2 7%左右。对于污染严重、易发生光化学烟雾的城郊附近 ,在阳光强烈的典型晴天 ,中午O3 浓度达到 2 0 0× 10 -9V/V时 ,即使气候条件不发生改变 ,CO2 浓度对作物光合作用的正效应也不足以弥补O3 浓度升高所造成的负效应 ,冠层光合速率将比目前干洁地区略有下降 ,如果进一步考虑光合作用有效辐射光谱成分下降至 0 .4左右 ,冠层光合作用将比目前的BASE值下降 35 %左右。 相似文献
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二氧化碳浓度增加对冬小麦生长发育影响的数值模拟 总被引：3，自引：1，他引：3
根据国内外小麦生长模拟研究成果,借鉴荷兰学者的模拟思路,从作物生长的主要生理过程人手,综合考虑气候变暖与大气中CO2浓度增加等因素对作物生长发育和产量形成的影响,修正了在一级生产水平下冬小麦生长模拟模式,使得模式能够对CO2浓度的变化做出相应的反应。经资料检验,在当前CO2浓度下,冬小麦总干重和穗干重的模拟平均相对误差小于10％,其它器官干重及叶面积指数的模拟也取得了较好的结果。运用改进后的模式模拟试验了未来气候变暖和CO2倍增对冬小麦生长发育的可能影响。 相似文献
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种植不同作物对农田N2O和CH4排放的影响及其驱动因子 总被引：3，自引：0，他引：3
以种植玉米(Zea mays)、大豆(Glycine max)和水稻(Oryza sativa)的农田生态系统为研究对象,于2003年6~10月系统观测了N2O和CH4的排放、土壤温度和湿度以及相关的生物学因子。玉米和水稻分别施化肥氮300 kg.hm-2,大豆未施氮肥。研究结果表明,作物类型对农田N2O和CH4排放具有显著的影响。土壤-玉米系统、土壤-大豆系统和土壤-水稻系统的N2O季节性平均排放通量分别为620.5±57.6、338.0±7.5和238.8±13.6μg.m-2.h-1(N2O)。种植作物促进了农田生态系统的N2O排放,玉米地土壤和裸地土壤的N2O平均排放通量分别为364.2±11.7和163.7±10.5μg.m-2.h-1(N2O)。土壤-玉米系统、土壤-水稻系统、玉米地土壤和裸地土壤N2O排放受土壤温度的影响,与土壤湿度无显著统计相关,但受土壤温度和水分的综合影响。土壤-大豆系统N2O排放随作物绿叶干重的增加而指数增加,与土壤温度和水分条件无统计相关,由大豆作物自身氮代谢所产生的N2O-N季节总量约为6.2 kg.hm-2(N)。土壤-水稻系统CH4平均排放通量为1.7±0.1 mg.m-2.h-1(CH4),烤田抑制了稻田CH4的排放。烤田前影响稻田CH4排放的主要因素是水稻生物量,烤田后的浅水灌溉及湿润灌溉阶段的CH4排放与土壤温度和水稻生物量无关。本研究未观测到旱作农田有吸收CH4的现象。 相似文献
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Vapor pressure deficit (VPD) is a widely used measure of atmospheric water demand. It is closely related to crop evapotranspiration and consequently has major impacts on crop growth and yields. Most previous studies have focused on the impacts of temperature, precipitation, and solar radiation on crop yields, but the impact of VPD is poorly understood. Here, we investigated the spatial and temporal changes in VPD and their impacts on yields of major crops in China from 1980 to 2008. The results showed that VPD during the growing period of rice, maize, and soybean increased by more than 0.10 kPa (10 yr)–1 in northeastern and southeastern China, although it increased the least during the wheat growing period. Increases in VPD had different impacts on yields for different crops and in different regions. Crop yields generally decreased due to increased VPD, except for wheat in southeastern China. Maize yield was sensitive to VPD in more counties than other crops. Soybean was the most sensitive and rice was the least sensitive to VPD among the major crops. In the past three decades, due to the rising trend in VPD, wheat, maize, and soybean yields declined by more than 10.0% in parts of northeastern China and the North China Plain, while rice yields were little affected. For China as a whole, the trend in VPD during 1980–2008 increased rice yields by 1.32%, but reduced wheat, maize, and soybean yields by 6.02%, 3.19%, and 7.07%, respectively. Maize and soybean in the arid and semi-arid regions in northern China were more sensitive to the increase in VPD. These findings highlight that climate change can affect crop growth and yield through increasing VPD, and water-saving technologies and agronomic management need to be strongly encouraged to adapt to ongoing climate change. 相似文献
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The Effect of Spatial Scale of Climatic Change Scenarios on Simulated Maize, Winter Wheat, and Rice Production in the Southeastern United States 总被引：2，自引：0，他引：2
E. A. Tsvetsinskaya L. O. Mearns T. Mavromatis W. Gao L. McDaniel M. W. Downton 《Climatic change》2003,60(1-2):37-72
We use the CERES family of crop models to assess the effect of different spatial scales of climate change scenarios on the simulated yield changes of maize (Zea mays L.), winter wheat (Triticum aestivum L.),and rice (Oryza sativa L.) in the Southeastern United States. The climate change scenarios were produced with the control and doubled CO2 runs of a high resolution regional climate model anda coarse resolution general circulation model, which provided the initial and lateral boundary conditions for the regional model. Three different cases were considered for each scenario: climate change alone, climate change plus elevated CO2, and the latter with adaptations. On the state level,for most cases, significant differences in the climate changed yields for corn were found, the coarse scale scenario usually producing larger modeled yield decreases or smaller increases. For wheat, however, which suffered large decreases in yields for all cases, very little contrast in yield based on scale of scenario was found. Scenario scale resulted in significantly different rice yields, but mainly because of low variability in yields. For maize the primary climate variable that explained the contrast in the yields calculated from the two scenarios is the precipitation during grain fill leading to different water stress levels. Temperature during vernalization explains some contrasts in winter wheat yields. With adaptation, the contrasts in the yields of all crops produced by the scenarios were reduced but not entirely removed. Our results indicate that spatial resolution of climate change scenarios can be an important uncertainty in climate change impact assessments, depending on the crop and management conditions. 相似文献
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Numerical Simulation Study on the Impacts of Tropospheric O_3 and CO_2 Concentration Changes on Winter Wheat. Part Ⅱ: Simulation Results and Analyses 
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下载免费PDF全文 With the rapid development of industrialization and urbanization, the enrichment of tropospheric ozone and carbon dioxide concentration at striking rates has caused effects on biosphere, especially on crops. It is generally accepted that the increase of CO2 concentration will have obverse effects on plant productivity while ozone is reported as the air pollutant most damaging to agricultural crops and other plants. The Model of Carbon and Nitrogen Biogeochemistry in Agroecosystems (DNDC) was adapted to evaluate simultaneously impacts of climate change on winter wheat. Growth development and yield formation of winter wheat under different O3 and CO2 concentration conditions are simulated with the improved DNDC model whose structure has been described in another paper. Through adjusting the DNDC model applicability, winter wheat growth and development in Gucheng Station were simulated well in 1993 and 1999, which is in favor of modifying the model further. The model was validated against experiment observation, including development stage data, leaf area index, each organ biomass, and total aboveground biomass. Sensitivity tests demonstrated that the simulated results in development stage and biomass were sensitive to temperature change. The main conclusions of the paper are the following: 1) The growth and yield of winter wheat under CO2 concentration of 500 ppmv, 700 ppmv and the current ozone concentration are simulated respectively by the model. The results are well fitted with the observed data of OTCs experiments. The results show that increase of CO2 concentration may improve the growth of winter wheat and elevate the yield. 2) The growth and yield of winter wheat under O3 concentration of 50 ppbv, 100 ppbv, 200 ppbv and the based concentration CO2 are simulated respectively by the model. The simulated curves of stem, leaf, and spike organs growth as well as leaf area index are well accounted with the observed data. The results reveal that ozone has negative effects on the growth and yield of winter wheat. Ozone accelerates the process of leaf senescence and causes yield loss. Under very high ozone concentration, crops are damaged dramatically and even dead. 3) At last, by the model possible effects of air temperature change and combined effects of O3 and CO2 are estimated respectively. The results show that doubled CO2 concentration may alleviate negative effect of O3 on biomass and yield of winter wheat when ozone concentration is about 70-80 ppbv. The obverse effects of CO2 are less than the adverse effects of O3 when the concentration of ozone is up to 100 ppbv. Future work should determine whether it can be applied to other species by adjusting the values of related parameters, and whether the model can be adapted to predict ozone effects on crops in farmland environment. 相似文献
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WANG Chunyi BAI Yueming GUO Jianping WEN Min HUO Zhiguo LIU Jiangge LI Lei 《Acta Meteorologica Sinica》2004,18(1):105-116
The controlled simulation experiments revealed that ozone concentration increases cause various degrees of injury to leaves of crop and vegetable.The injury to vegetables is greater than that to crops.Ozone can dramatically affect stomatal conductance,photosynthetic rate and transpiration rate,and consequently the yield of crops.No matter how long exposure time was, stomatal conductance increased and photosynthetic and transpiration rates decreased with increases in ozone concentration.When ozone concentration was 100 nmol/mol,yields of rice and winter wheat declined by 27.1% and 60.5% respectively.When up to 200 nmol/mol,there was a significant reduction of yields:a decline up to 33.7% for rice and 81.3% for winter wheat.On the other hand,ozone benefits the improvement of grain quality such as amino acid and protein. 相似文献
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Numerical Simulation Study on the Impacts of Tropospheric O3 and CO2 Concentration Changes on Winter Wheat. Part II: Simulation Results and Analyses 下载免费PDF全文
下载免费PDF全文 With the rapid development of industrialization and urbanization, the enrichment of tropospheric ozone and carbon dioxide concentration at striking rates has caused effects on biosphere, especially on crops. It is generally accepted that the increase of CO2 concentration will have obverse effects on plant productivity while ozone is reported as the air pollutant most damaging to agricultural crops and other plants. The Model of Carbon and Nitrogen Biogeochemistry in Agroecosystems (DNDC) was adapted to evaluate simultaneously impacts of climate change on winter wheat. Growth development and yield formation of winter wheat
under different O3 and CO2 concentration conditions are simulated with the improved DNDC model whose structure has been described in another paper. Through adjusting the DNDC model applicability, winter wheat growth and development in Gucheng Station were simulated well in 1993 and 1999, which is in favor of modifying the model further. The model was validated against experiment observation, including development stage data, leaf area index, each organ biomass, and total aboveground biomass. Sensitivity tests demonstrated that the simulated results in development stage and biomass were sensitive to temperature change. The main conclusions of the paper are the following: 1) The growth and yield of winter wheat under CO2 concentration of 500 ppmv, 700 ppmv and the current ozone concentration are simulated respectively by the model. The results are well fitted with the observed data of OTCs experiments. The results show that increase of CO2 concentration may improve the growth of winter wheat and elevate the yield. 2) The growth and yield of winter wheat under O3 concentration of 50 ppbv, 100 ppbv, 200 ppbv and the based concentration CO2 are simulated respectively by the model. The simulated curves of stem, leaf, and spike organs growth as well as leaf area index are well accounted with the observed data. The results reveal that ozone has negative e ects on the growth and yield of winter wheat. Ozone accelerates the process of leaf senescence and causes yield loss. Under very high ozone concentration, crops are damaged dramatically and even dead. 3) At last, by the model possible effects of air temperature change and combined effects of O3 and CO2 are estimated respectively. The results show that doubled CO2 concentration may alleviate negative effect of O3 on biomass and yield of winter wheat when ozone concentration is about 70-80 ppbv. The obverse effects of CO2 are less than the adverse effects of O3 when the concentration of ozone is up to 100 ppbv. Future work should determine whether it can be applied to other species by adjusting the values of related parameters, and whether the model can be adapted to predict ozone e ects on crops in farmland environment. 相似文献
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WOLFRAM SCHÜßLER ROLF NEUBERT INGEBORG LEVIN NATALIE FISCHER CHRISTIAN SONNTAG 《Tellus. Series B, Chemical and physical meteorology》2000,52(3):909-918
The amounts of microbial and root‐respired CO2 in a maize/winter wheat agricultural system in south western Germany were investigated by measurements of the CO2 mixing ratio and the 13 C/12 C ratio in soil air. CO2 fluxes at the soil surface for the period of investigation (1993–1995) were also determined. Root respired CO2 shows a strong correlation with the plant mass above ground surface of the respective vegetation (R2 ≥0.88); the maximum CO2 release from roots was in August for the maize (2.0±0.5 mmol m−2 h−1 ) and in June for winter wheat (1.5±0.5 mmol m−2 h−1 ). Maximum CO2 production by roots correlate well with the maximum amount of plant root matter. Integrating the CO2 production over the whole growing season and normalizing to the dry root matter yields, the CO2 production per gram dry organic root matter (DORM) of maize was found to be 0.14±0.03 gC (g DORM)−1 . At the sites investigated, root‐produced CO2 contributed (16±4)% for maize, and (24±4)% for winter wheat, respectively, to the total annual CO2 production in the soil (450±50 gC m−2 for maize, 210±30 gC m−2 for winter wheat). 相似文献
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采用最大可能蒸散、作物实际蒸散、水分盈亏、水分订正系数评价了黄土高原多沙粗沙区主要作物(春小麦、冬小麦、春玉米、夏玉米和棉花)和草地生长季水分供需状况,结果表明,需水量:冬小麦>棉花>春玉米>春小麦>夏玉米;水分订正系数:春玉米>夏玉米>棉花>春小麦>冬小麦。草地需水量为350～450mm,水分订正系数0.95以上,水分供需矛盾小,实施退耕还牧无论对缓解水资源短缺,还是改善生态环境,在黄土高原多沙粗沙区都是十分有效的措施。 相似文献
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用Priestley—Taylor公式估算作物农田蒸散量的研究 总被引：2，自引：0，他引：2
利用田间试验资料，综合考虑了影响农田蒸散的气象，作物和土壤因素，并以Ｐｒｉｅｓｔｌｅｙ－Ｔａｙｌｏｒ公式为基础，建立了不同作物（棉花、玉米冬小麦）的农田散估算模型。该模型仅需常规气象和农业气象资料，计算简便，具有一定的实用价值。 相似文献