At a rice wheat rotational free air CO 2 enrichment(FACE) platform, the effect of elevated atmospheric CO 2 on soil nematode communities in a farmland ecosystem was studied. Wheat plots were exposed to elevated atmosp...At a rice wheat rotational free air CO 2 enrichment(FACE) platform, the effect of elevated atmospheric CO 2 on soil nematode communities in a farmland ecosystem was studied. Wheat plots were exposed to elevated atmospheric CO 2(ambient 370 μl/L + 200 μl/L). 32 families and 40 genera of nematode were observed in soil suspensions during the study period. Under FACE treatment, the numbers of total nematodes, bacterivores and fungivores exhibited an increasing trend. Because of the seasonal variation of soil temperature and moisture, the effect of elevated atmospheric CO 2 on soil nematodes was only observed under favorable conditions. The response of nematode communities to elevated atmospheric CO 2 may indicate the change of soil food web.展开更多
A hydroponics experiment was conducted to investigate the rice root growth in FACE (free-air carbon dioxide enrichment). The root biomass, root volume, ratio of root/shoot, number of adventitious roots and root diam...A hydroponics experiment was conducted to investigate the rice root growth in FACE (free-air carbon dioxide enrichment). The root biomass, root volume, ratio of root/shoot, number of adventitious roots and root diameter significantly increased under FACE conditions, while the CO2 enrichment decreased the N concentration in rice roots without any change in the C content, leading to an increase in root C:N ratio. Moreover, the elevated CO2 resulted in a remarkable decrease of root activity, expressed as per unit root dry weight, which might be responsible for decreased N concentration in roots.展开更多
人类活动导致的大气和气候变化将极大地改变作物的生长环境,其中最大的一个变化就是大气二氧化碳(CO2)浓度的迅速上升:从工业革命前的平均270μmol/mol上升到目前的381μmol/mol,到2050年至少超过550μmol/mol。FACE(Free-air CO2 enric...人类活动导致的大气和气候变化将极大地改变作物的生长环境,其中最大的一个变化就是大气二氧化碳(CO2)浓度的迅速上升:从工业革命前的平均270μmol/mol上升到目前的381μmol/mol,到2050年至少超过550μmol/mol。FACE(Free-air CO2 enrichment,开放式空气中CO2浓度增高)试验是目前评估未来高浓度CO2对作物生长和产量实际影响的最佳方法。水稻无疑是人类最重要的食物来源,迄今为止人类利用FACE技术开展水稻响应和适应的研究已有10a(19982008年)的历史。以生长发育为主线,首次系统综述了10a水稻FACE试验在该领域的研究成果,总结了FACE情形下高浓度CO2(模拟本世纪中叶大气CO2浓度)对主要供试水稻品种(小区面积大于4m2)光合作用、生育进程、地上部生长、地下部生长、物质分配、籽粒灌浆、产量构成以及倒伏性状等影响的研究进展,比较了FACE与非FACE研究之间以及中国和日本FACE研究(世界上唯一的两个大型水稻FACE研究)之间的异同点。根据研究进展以及当前的技术水平,文章最后提出了该领域的3个优先课题:(1)FACE情形下杂交稻生产力响应高于预期的生物学机制;(2)FACE情形下CO2与主要栽培措施的互作效应;(3)FACE情形下CO2与主要空气污染物臭氧的互作效应。这些响应的机理性解析将有助于从根本上减少人类预测未来粮食安全的不确定性,进而更加有效地制订出应对全球变化的适应策略。展开更多
大气二氧化碳(CO2)浓度升高使水稻产量增加,但这种影响是否因不同栽培条件而异尚不清楚。2011年利用中国稻田FACE(Free Air CO2Enrichment)系统平台,以敏感水稻品种汕优63为供试材料,二氧化碳设环境CO2浓度(Ambient)和高CO2浓度(Ambient...大气二氧化碳(CO2)浓度升高使水稻产量增加,但这种影响是否因不同栽培条件而异尚不清楚。2011年利用中国稻田FACE(Free Air CO2Enrichment)系统平台,以敏感水稻品种汕优63为供试材料,二氧化碳设环境CO2浓度(Ambient)和高CO2浓度(Ambient+200μmol·mol-1),施氮量设低氮(15 g·m-2)和高氮(25 g·m-2),移栽密度设低密度(16穴·m-2)和高密度(24穴·m-2),研究了不同栽培条件下大气CO2浓度升高对杂交水稻产量形成的影响。结果表明:高浓度CO2对水稻抽穗期和成熟期没有影响,但使结实期株高显著增高(+7%);使单位面积穗数(+8%)和每穗颖花数(+19%)明显增多,进而使单位面积颖花量大幅增加(+29%)。高浓度CO2条件下穗数增多主要与最高分蘖数明显增加有关,而分蘖成穗率显著下降;穗型增大主要由单茎干重而非单位干重形成的颖花数增加所致。高浓度CO2环境下水稻结实能力呈增加趋势,其中平均粒重的增幅达显著水平。大气CO2浓度升高使水稻籽粒产量平均增加36%,其中在低氮低密度、低氮高密度、高氮低密度和高氮高密度条件下分别增加43%、46%、34%、23%。增施氮肥或增加移栽密度使水稻产量略有下降,但均未达显著水平。以上结果表明,高浓度CO2环境下杂交水稻因库容量增大导致产量大幅增加,调整施氮水平和移栽密度可在一定程度上改变这种肥料效应。展开更多
Background:Increasing atmospheric[CO_(2)]can increase photosynthesis and promote plant growth,consequently influencing nitrogen(N)cycling.Yet,there is no systematic information on the N response among different organs...Background:Increasing atmospheric[CO_(2)]can increase photosynthesis and promote plant growth,consequently influencing nitrogen(N)cycling.Yet,there is no systematic information on the N response among different organs of japonica and indica rice genotypes to elevated[CO_(2)]as affected by N application.To investigate the impacts of elevated[CO_(2)]and N fertilization on N uptake and utilization of different genotypic rice(Oryza sativa L.)during grain filling,a free-air CO_(2) enrichment(FACE)experiment with indica cv.Liangyou 084(IIY084)and japonica cv.Wuyunjing 23(WYJ23)was conducted in Eastern China.Crops were exposed to ambient[CO_(2)]and elevated[CO_(2)](200μmol mol^(−1) above ambient)at two levels of N:control(0N)and 22.5 g N m^(−2)(normal N,NN),and they were sampled at 82 days after transplanting(DAT),99 DAT,and maturity,respectively.Results:Under FACE,significant declines of N concentration in all tissues and the whole plants were observed with the greater decrease in leaves and stems at three stages.Positive responses of N use efficiency(NUE)to elevated[CO_(2)]were recorded over the study period.The total N accumulation remained unchanged,while a large amount of N was partitioned to panicles at the expense of leaves and stems.As compared to WYJ23,greater N transportation from roots to aboveground,especially the panicles,was observed on IIY084 accompanied by higher panicle biomass(82 DAT and 99 DAT),N concentrations(maturity),and greater NUE for leaves through the study season.Across all[CO_(2)]and cultivars,N fertilization increased N partitioning to leaves and stems while decreasing that to panicles.Additionally,N supply decreased NUE while stimulating N concentrations and N amounts of rice plants.Among all treatments,IIY084 had the highest N accumulation and allocation in panicles under elevated[CO_(2)]in combination with N fertilizer at maturity.Conclusion:Data from this study were helpful for understanding the temporal N uptake and utilization of different rice genotypes as affected by N availability and suggest that IIY084 promises a considerable prospect for its grain yield and quality under future elevated atmospheric[CO_(2)].展开更多
人类活动导致的大气和气候变化将极大地改变作物未来的生长环境,其中一个显著的变化就是近地层空气污染物臭氧浓度的迅速上升:从工业革命前低于10nL/L上升到现在的50nL/L(夏季每天8h平均),最新预测这一浓度将在2015-2050年增加20%-25%,...人类活动导致的大气和气候变化将极大地改变作物未来的生长环境,其中一个显著的变化就是近地层空气污染物臭氧浓度的迅速上升:从工业革命前低于10nL/L上升到现在的50nL/L(夏季每天8h平均),最新预测这一浓度将在2015-2050年增加20%-25%,本世纪末将增加40%-60%。目前大气背景臭氧浓度已经超过敏感植物的伤害阀值(即40nL/L),广泛地造成农作物减产,而未来臭氧浓度增加将使这种影响变得更为严重。与封闭式和开顶式试验相比,FACE(free-air gas concentration enrichment)研究使用标准的作物管理技术,在完全开放的农田条件下运行,代表了人类对未来大气环境的最好模拟。作为人类食物蛋白的重要来源,大豆是世界上种植面积最大的双子叶植物,也是1年生C3作物的模式作物,同时也被认为对臭氧污染最为敏感的作物之一。美国伊利诺伊大学的大豆FACE(SoyFACE)是世界上第1个利用FACE技术开展农作物对高浓度臭氧(模拟本世纪中叶近地层臭氧浓度)响应和适应的多学科合作研究。在阐述气室研究的局限性和介绍SoyFACE运行特点的基础上,首次综述了FACE情形下高浓度臭氧对大豆光合特性、冠层结构、物质生产与分配、产量及其构成因素以及虫害等方面的影响,并比较了FACE与气室研究结果的异同点。SoyFACE研究清楚地表明臭氧对未来粮食安全的影响必须作为一个重要的全球变化因子来加以考虑。利用FACE技术深入开展臭氧及其与其它全球变化因子的互作对世界主要粮食作物的影响、机制和调控的系统研究,是该领域未来优先考虑的方向。展开更多
利用稻田FACE(Free Air CO_2 Enrichment)平台,以创造世界高产纪录的超级稻组合‘Y两优2号’为试验材料,CO_2处理设环境CO_2浓度[(382.5±2.0)μmol·mol-1]和高CO_2浓度(增200μmol·mol-1)两个水平,齐穗期源库改变设对照...利用稻田FACE(Free Air CO_2 Enrichment)平台,以创造世界高产纪录的超级稻组合‘Y两优2号’为试验材料,CO_2处理设环境CO_2浓度[(382.5±2.0)μmol·mol-1]和高CO_2浓度(增200μmol·mol-1)两个水平,齐穗期源库改变设对照、剪除剑叶(剪1叶)、剪除所有功能叶(剪3叶)以及相间剪除一次枝梗(疏花),研究开放条件下高CO_2浓度对不同源库处理水稻产量及其构成因子的影响。结果表明,对没有进行剪叶疏花处理的水稻(即对照)而言,高CO_2浓度使‘Y两优2号’籽粒产量平均增加12%,这主要与每穗颖花数和结实能力均略有增加有关。高CO_2浓度使剪1叶、剪3叶处理水稻的产量分别增加26%和57%,这主要与饱粒率和所有籽粒平均粒重均大幅增加有关。对齐穗期疏花处理水稻而言,高CO_2浓度导致的产量增幅与对照水稻接近。与对照相比,齐穗期剪1叶、剪3叶处理使水稻籽粒产量分别降低17%和52%,均达极显著水平,这主要与饱粒率和所有籽粒平均粒重均显著下降有关;尽管齐穗期疏花处理使水稻结实能力显著增加,但因每穗颖花数减半,产量大幅下降(-29%)。籽粒最终产量对高CO_2浓度的响应与饱粒率和所有籽粒平均粒重的响应呈显著正相关。以上结果表明,水稻齐穗期人为改变源库比例(特别是剪叶)可以改变籽粒结实能力和最终产量对高CO_2浓度的响应。展开更多
Increasing attentions have been paid to mineral concentration decrease in milled rice grains caused by CO2 enrichment, but the mechanisms still remain unclear. Therefore, mineral (Ca, Mg, Fe, Zn and Mn) translocatio...Increasing attentions have been paid to mineral concentration decrease in milled rice grains caused by CO2 enrichment, but the mechanisms still remain unclear. Therefore, mineral (Ca, Mg, Fe, Zn and Mn) translocation in plant-soil system with a FACE (Free-air CO2 enrichment) experiment were investigated in Eastern China after 4-yr operation. Results mainly showed that: (1) elevated CO2 significantly increased the biomass of stem and panicle by 21.9 and 24.0%, respectively, but did not affect the leaf biomass. (2) Elevated CO2 significantly increased the contents of Ca, Mg, Fe, Zn, and Mn in panicle by 61.2, 28.9, 87.0, 36.7, and 66.0%, respectively, and in stem by 13.2, 21.3, 47.2, 91.8, and 25.2%, respectively, but did not affect them in leaf. (3) Elevated CO2 had positive effects on the weight ratio of mineral/biomass in stem and panicle. Our results suggest that elevated CO2 can favor the translocation of Ca, Mg, Fe, Zn, and Mn from soil to stem and panicle. The CO2-led mineral decline in milled rice grains may mainly attribute to the CO2-1ed unbalanced stimulations on the translocations of minerals and carbohydrates from vegetative parts (e.g., leaf, stem, branch and husk) to the grains.展开更多
Abstract Methane (CH4) emissions from paddy rice fields substantially contribute to the dramatic increase of this greenhouse gas in the atmosphere. Due to great concern about climate change, it is necessary to predi...Abstract Methane (CH4) emissions from paddy rice fields substantially contribute to the dramatic increase of this greenhouse gas in the atmosphere. Due to great concern about climate change, it is necessary to predict the effects of the dramatic increase in atmospheric carbon dioxide (CO2) on CH4 emissions from paddy rice fields. CH4MOD 1.0 is the most widely validated model for simulating CH4 emissions from paddy rice fields exposed to ambient CO2 (hereinafter referred to as aCO2). We upgraded the model to CH4MOD 2.0 by: (a) modifying the description of the influences of soil Eh and the water regime on CH4 production; (b) adding new features to reflect the regulatory effects of atmospheric CO2 upon methanogenic substrates, soil Eh during drainages, and vascular CH4 transport; and (c) adding a new feature to simulate the influences of nitrogen (N) addition rates on methanogenic substrates under elevated CO2 (hereinafter referred to as eCO2) condition. Validation with 109 observation cases under aC02 condition showed that CHaMOD 2.0 possessed a minor systematic bias in the prediction of seasonally accumulated methane emissions (SAM). Validation with observations in free-air CO2 enrichment (FACE) experiments in temperate and subtropical climates showed that CH4MOD 2.0 successfully simulated the effects of eCO2 upon SAM from paddy rice fields incorporated with various levels of previous crop residues and/or N fertilizer. Our results imply that CH4MOD 2.0 provides a potential approach for estimating of the effects of elevated atmospheric CO2 upon CHa emissions from regional or global paddy rice fields with various management practices in a changing climate.展开更多
不断升高的大气CO2浓度影响水稻颖花发育、灌浆结实和品质形成,但这种影响是否与籽粒在稻穗上的着生部位有关尚不清楚.利用稻田FACE(Free-Air CO2 Enrichment)平台,以优质丰产粳稻‘武运粳23’为材料,CO2处理设背景CO2浓度(Ambient)和高...不断升高的大气CO2浓度影响水稻颖花发育、灌浆结实和品质形成,但这种影响是否与籽粒在稻穗上的着生部位有关尚不清楚.利用稻田FACE(Free-Air CO2 Enrichment)平台,以优质丰产粳稻‘武运粳23’为材料,CO2处理设背景CO2浓度(Ambient)和高CO2浓度(增200μmol·mol^-1,FACE)两个水平,研究开放大田条件下高浓度CO2对水稻颖花密度、籽粒结实能力、稻米外观和食味品质的影响及其与稻穗不同着生位置的关系.结果表明:FACE处理使武运粳23籽粒产量平均增加18.3%,从产量构成因素看,穗数和饱粒重分别增加21.4%、9.4%,每穗颖花数、饱粒率平均减少9.0%、2.2%.FACE水稻饱粒率下降主要与稻穗不同部位空粒率大幅增加有关.FACE水稻每穗颖花数减少主要与稻穗上部、中部二次枝梗现存颖花大幅减少有关,而其他位置颖花数均无显著变化;稻穗不同位置饱粒重和饱粒率对FACE的响应无显著差异.FACE处理使绿粒率下降,但糙米长度和宽度均增加,稻穗不同部位趋势一致.FACE使垩白粒率(增幅59%)、垩白度(增幅55%)均极显著增加,增幅表现为稻穗一次枝梗>二次枝梗、上部>中部>下部.FACE使稻穗不同位置稻米直链淀粉含量略增,使最高粘度、热浆粘度、崩解值、最终粘度和消减值略降,但多未达显著水平.FACE使稻米糊化温度显著下降,弱势粒的降幅大于强势粒.综上,高浓度CO2环境下武运粳23产量增加主要与穗数增多和籽粒增重有关,而稻穗明显变小;高浓度CO2使稻米绿粒率减少,垩白增多,而对蒸煮食味品质影响较少;颖花着生位置对高浓度CO2环境下水稻颖花发育、结实和品质的影响因不同测定指标而异.展开更多
To examine how the major elements of global change affect herbivory in agroecosystems, a multifactorial experiment was conducted where soybeans were grown at two levels of carbon dioxide and temperature, including tho...To examine how the major elements of global change affect herbivory in agroecosystems, a multifactorial experiment was conducted where soybeans were grown at two levels of carbon dioxide and temperature, including those predicted for 2050, under otherwise normal field conditions. Japanese beetles (Popillia japonica Newman) were enclosed on foliage for 24 h, after which the beetle survivorship, total and per capita leaf consumption, and leaf protease inhibitor activity were measured. The direct effect of temperature on beetle consumption and survivorship also was measured under controlled environmental conditions. No differences in total foliage consumption were observed; however, beetles forced to feed at elevated temperature in the field demonstrated greater per capita consmnption and reduced survivorship compared to beetles feeding at ambient temperature. Survivorship was also greater for beetles that consumed foliage grown under elevated CO2, but there were no interactive effects of CO2 and temperature, and no differences in leaf chemistry were resolved. Leaf consumption by beetles increased strongly with increasing temperature up to -37℃, above which increased mortality caused a precipitous decrease in consumption. An empirical model based on the temperature dependence of leaf consumption and flight suggests that the 3.5℃ increase in temperature predicted for 2050 will increase the optimal feeding window for the Japanese beetle by 290%. Elevated temperature and CO2 operating independently have the potential to greatly increase foliage damage to soybean by chewing insects, such as Popilliajaponica, potentially affecting crop yields.展开更多
Annual wormwood(Artemisia annua L.) is the only viable source of artemisinin,an antimalarial drug.There is a pressing need to optimize production per cultivated area of this important medicinal plant;however,the effec...Annual wormwood(Artemisia annua L.) is the only viable source of artemisinin,an antimalarial drug.There is a pressing need to optimize production per cultivated area of this important medicinal plant;however,the effect of increasing atmospheric carbon dioxide(CO_2) concentration on its growth is still unclear.Therefore,a pot experiment was conducted in a free-air CO2 enrichment(FACE) facility in Yangzhou City,China.Two A.annua varieties,one wild and one cultivated,were grown under ambient(374μmol mol^(-1)) and elevated(577 μmol mol^(-1)) CO_2 levels to determine the dry matter accumulation and macronutrient uptake of aerial parts.The results showed that stem and leaf yields of both A.annua varieties increased significantly under elevated CO_2 due to the enhanced photosynthesis rate.Although nitrogen(N),phosphorus(P),and potassium(K) concentrations in leaves and stems of both varieties decreased under elevated CO_2,total shoot N,P,and K uptake of the two varieties were enhanced and the ratios among the concentrations of these nutrients(N:P,N:K,and P:K) were not affected by elevated CO_2.Overall,our results provided the evidence that elevated CO_2 increased biomass and shoot macronutrient uptake of two A.annua varieties.展开更多
文摘At a rice wheat rotational free air CO 2 enrichment(FACE) platform, the effect of elevated atmospheric CO 2 on soil nematode communities in a farmland ecosystem was studied. Wheat plots were exposed to elevated atmospheric CO 2(ambient 370 μl/L + 200 μl/L). 32 families and 40 genera of nematode were observed in soil suspensions during the study period. Under FACE treatment, the numbers of total nematodes, bacterivores and fungivores exhibited an increasing trend. Because of the seasonal variation of soil temperature and moisture, the effect of elevated atmospheric CO 2 on soil nematodes was only observed under favorable conditions. The response of nematode communities to elevated atmospheric CO 2 may indicate the change of soil food web.
基金National Natural Science Foundation of China (nos. 40231003 , 40110817) Knowledge Innovation Program of Chinese Academy of Sciences (no. KZCX2-408) the National Key Project on Basic Sciences (no. 2002CB714003).
文摘A hydroponics experiment was conducted to investigate the rice root growth in FACE (free-air carbon dioxide enrichment). The root biomass, root volume, ratio of root/shoot, number of adventitious roots and root diameter significantly increased under FACE conditions, while the CO2 enrichment decreased the N concentration in rice roots without any change in the C content, leading to an increase in root C:N ratio. Moreover, the elevated CO2 resulted in a remarkable decrease of root activity, expressed as per unit root dry weight, which might be responsible for decreased N concentration in roots.
文摘人类活动导致的大气和气候变化将极大地改变作物的生长环境,其中最大的一个变化就是大气二氧化碳(CO2)浓度的迅速上升:从工业革命前的平均270μmol/mol上升到目前的381μmol/mol,到2050年至少超过550μmol/mol。FACE(Free-air CO2 enrichment,开放式空气中CO2浓度增高)试验是目前评估未来高浓度CO2对作物生长和产量实际影响的最佳方法。水稻无疑是人类最重要的食物来源,迄今为止人类利用FACE技术开展水稻响应和适应的研究已有10a(19982008年)的历史。以生长发育为主线,首次系统综述了10a水稻FACE试验在该领域的研究成果,总结了FACE情形下高浓度CO2(模拟本世纪中叶大气CO2浓度)对主要供试水稻品种(小区面积大于4m2)光合作用、生育进程、地上部生长、地下部生长、物质分配、籽粒灌浆、产量构成以及倒伏性状等影响的研究进展,比较了FACE与非FACE研究之间以及中国和日本FACE研究(世界上唯一的两个大型水稻FACE研究)之间的异同点。根据研究进展以及当前的技术水平,文章最后提出了该领域的3个优先课题:(1)FACE情形下杂交稻生产力响应高于预期的生物学机制;(2)FACE情形下CO2与主要栽培措施的互作效应;(3)FACE情形下CO2与主要空气污染物臭氧的互作效应。这些响应的机理性解析将有助于从根本上减少人类预测未来粮食安全的不确定性,进而更加有效地制订出应对全球变化的适应策略。
文摘大气二氧化碳(CO2)浓度升高使水稻产量增加,但这种影响是否因不同栽培条件而异尚不清楚。2011年利用中国稻田FACE(Free Air CO2Enrichment)系统平台,以敏感水稻品种汕优63为供试材料,二氧化碳设环境CO2浓度(Ambient)和高CO2浓度(Ambient+200μmol·mol-1),施氮量设低氮(15 g·m-2)和高氮(25 g·m-2),移栽密度设低密度(16穴·m-2)和高密度(24穴·m-2),研究了不同栽培条件下大气CO2浓度升高对杂交水稻产量形成的影响。结果表明:高浓度CO2对水稻抽穗期和成熟期没有影响,但使结实期株高显著增高(+7%);使单位面积穗数(+8%)和每穗颖花数(+19%)明显增多,进而使单位面积颖花量大幅增加(+29%)。高浓度CO2条件下穗数增多主要与最高分蘖数明显增加有关,而分蘖成穗率显著下降;穗型增大主要由单茎干重而非单位干重形成的颖花数增加所致。高浓度CO2环境下水稻结实能力呈增加趋势,其中平均粒重的增幅达显著水平。大气CO2浓度升高使水稻籽粒产量平均增加36%,其中在低氮低密度、低氮高密度、高氮低密度和高氮高密度条件下分别增加43%、46%、34%、23%。增施氮肥或增加移栽密度使水稻产量略有下降,但均未达显著水平。以上结果表明,高浓度CO2环境下杂交水稻因库容量增大导致产量大幅增加,调整施氮水平和移栽密度可在一定程度上改变这种肥料效应。
基金National Basic Research Program of China(2014CB954500)National Natural Science Foundation of China(31261140364,31370457).
文摘Background:Increasing atmospheric[CO_(2)]can increase photosynthesis and promote plant growth,consequently influencing nitrogen(N)cycling.Yet,there is no systematic information on the N response among different organs of japonica and indica rice genotypes to elevated[CO_(2)]as affected by N application.To investigate the impacts of elevated[CO_(2)]and N fertilization on N uptake and utilization of different genotypic rice(Oryza sativa L.)during grain filling,a free-air CO_(2) enrichment(FACE)experiment with indica cv.Liangyou 084(IIY084)and japonica cv.Wuyunjing 23(WYJ23)was conducted in Eastern China.Crops were exposed to ambient[CO_(2)]and elevated[CO_(2)](200μmol mol^(−1) above ambient)at two levels of N:control(0N)and 22.5 g N m^(−2)(normal N,NN),and they were sampled at 82 days after transplanting(DAT),99 DAT,and maturity,respectively.Results:Under FACE,significant declines of N concentration in all tissues and the whole plants were observed with the greater decrease in leaves and stems at three stages.Positive responses of N use efficiency(NUE)to elevated[CO_(2)]were recorded over the study period.The total N accumulation remained unchanged,while a large amount of N was partitioned to panicles at the expense of leaves and stems.As compared to WYJ23,greater N transportation from roots to aboveground,especially the panicles,was observed on IIY084 accompanied by higher panicle biomass(82 DAT and 99 DAT),N concentrations(maturity),and greater NUE for leaves through the study season.Across all[CO_(2)]and cultivars,N fertilization increased N partitioning to leaves and stems while decreasing that to panicles.Additionally,N supply decreased NUE while stimulating N concentrations and N amounts of rice plants.Among all treatments,IIY084 had the highest N accumulation and allocation in panicles under elevated[CO_(2)]in combination with N fertilizer at maturity.Conclusion:Data from this study were helpful for understanding the temporal N uptake and utilization of different rice genotypes as affected by N availability and suggest that IIY084 promises a considerable prospect for its grain yield and quality under future elevated atmospheric[CO_(2)].
文摘人类活动导致的大气和气候变化将极大地改变作物未来的生长环境,其中一个显著的变化就是近地层空气污染物臭氧浓度的迅速上升:从工业革命前低于10nL/L上升到现在的50nL/L(夏季每天8h平均),最新预测这一浓度将在2015-2050年增加20%-25%,本世纪末将增加40%-60%。目前大气背景臭氧浓度已经超过敏感植物的伤害阀值(即40nL/L),广泛地造成农作物减产,而未来臭氧浓度增加将使这种影响变得更为严重。与封闭式和开顶式试验相比,FACE(free-air gas concentration enrichment)研究使用标准的作物管理技术,在完全开放的农田条件下运行,代表了人类对未来大气环境的最好模拟。作为人类食物蛋白的重要来源,大豆是世界上种植面积最大的双子叶植物,也是1年生C3作物的模式作物,同时也被认为对臭氧污染最为敏感的作物之一。美国伊利诺伊大学的大豆FACE(SoyFACE)是世界上第1个利用FACE技术开展农作物对高浓度臭氧(模拟本世纪中叶近地层臭氧浓度)响应和适应的多学科合作研究。在阐述气室研究的局限性和介绍SoyFACE运行特点的基础上,首次综述了FACE情形下高浓度臭氧对大豆光合特性、冠层结构、物质生产与分配、产量及其构成因素以及虫害等方面的影响,并比较了FACE与气室研究结果的异同点。SoyFACE研究清楚地表明臭氧对未来粮食安全的影响必须作为一个重要的全球变化因子来加以考虑。利用FACE技术深入开展臭氧及其与其它全球变化因子的互作对世界主要粮食作物的影响、机制和调控的系统研究,是该领域未来优先考虑的方向。
文摘利用稻田FACE(Free Air CO_2 Enrichment)平台,以创造世界高产纪录的超级稻组合‘Y两优2号’为试验材料,CO_2处理设环境CO_2浓度[(382.5±2.0)μmol·mol-1]和高CO_2浓度(增200μmol·mol-1)两个水平,齐穗期源库改变设对照、剪除剑叶(剪1叶)、剪除所有功能叶(剪3叶)以及相间剪除一次枝梗(疏花),研究开放条件下高CO_2浓度对不同源库处理水稻产量及其构成因子的影响。结果表明,对没有进行剪叶疏花处理的水稻(即对照)而言,高CO_2浓度使‘Y两优2号’籽粒产量平均增加12%,这主要与每穗颖花数和结实能力均略有增加有关。高CO_2浓度使剪1叶、剪3叶处理水稻的产量分别增加26%和57%,这主要与饱粒率和所有籽粒平均粒重均大幅增加有关。对齐穗期疏花处理水稻而言,高CO_2浓度导致的产量增幅与对照水稻接近。与对照相比,齐穗期剪1叶、剪3叶处理使水稻籽粒产量分别降低17%和52%,均达极显著水平,这主要与饱粒率和所有籽粒平均粒重均显著下降有关;尽管齐穗期疏花处理使水稻结实能力显著增加,但因每穗颖花数减半,产量大幅下降(-29%)。籽粒最终产量对高CO_2浓度的响应与饱粒率和所有籽粒平均粒重的响应呈显著正相关。以上结果表明,水稻齐穗期人为改变源库比例(特别是剪叶)可以改变籽粒结实能力和最终产量对高CO_2浓度的响应。
基金supported by the National Natural Science Foundation of China (31200369)the Lecture and Study for Outstanding Scholars from Home and Abroad,Chinese Academy of Forestry (CAF),2014
文摘Increasing attentions have been paid to mineral concentration decrease in milled rice grains caused by CO2 enrichment, but the mechanisms still remain unclear. Therefore, mineral (Ca, Mg, Fe, Zn and Mn) translocation in plant-soil system with a FACE (Free-air CO2 enrichment) experiment were investigated in Eastern China after 4-yr operation. Results mainly showed that: (1) elevated CO2 significantly increased the biomass of stem and panicle by 21.9 and 24.0%, respectively, but did not affect the leaf biomass. (2) Elevated CO2 significantly increased the contents of Ca, Mg, Fe, Zn, and Mn in panicle by 61.2, 28.9, 87.0, 36.7, and 66.0%, respectively, and in stem by 13.2, 21.3, 47.2, 91.8, and 25.2%, respectively, but did not affect them in leaf. (3) Elevated CO2 had positive effects on the weight ratio of mineral/biomass in stem and panicle. Our results suggest that elevated CO2 can favor the translocation of Ca, Mg, Fe, Zn, and Mn from soil to stem and panicle. The CO2-led mineral decline in milled rice grains may mainly attribute to the CO2-1ed unbalanced stimulations on the translocations of minerals and carbohydrates from vegetative parts (e.g., leaf, stem, branch and husk) to the grains.
基金supported by the National Natural Science Foundation of China (40675075, 40425010)the Chinese Academy of Sciences (KZCX3-SW-440,KZCX2-yw-204)the European Union (NitroEurope IP 017841)
文摘Abstract Methane (CH4) emissions from paddy rice fields substantially contribute to the dramatic increase of this greenhouse gas in the atmosphere. Due to great concern about climate change, it is necessary to predict the effects of the dramatic increase in atmospheric carbon dioxide (CO2) on CH4 emissions from paddy rice fields. CH4MOD 1.0 is the most widely validated model for simulating CH4 emissions from paddy rice fields exposed to ambient CO2 (hereinafter referred to as aCO2). We upgraded the model to CH4MOD 2.0 by: (a) modifying the description of the influences of soil Eh and the water regime on CH4 production; (b) adding new features to reflect the regulatory effects of atmospheric CO2 upon methanogenic substrates, soil Eh during drainages, and vascular CH4 transport; and (c) adding a new feature to simulate the influences of nitrogen (N) addition rates on methanogenic substrates under elevated CO2 (hereinafter referred to as eCO2) condition. Validation with 109 observation cases under aC02 condition showed that CHaMOD 2.0 possessed a minor systematic bias in the prediction of seasonally accumulated methane emissions (SAM). Validation with observations in free-air CO2 enrichment (FACE) experiments in temperate and subtropical climates showed that CH4MOD 2.0 successfully simulated the effects of eCO2 upon SAM from paddy rice fields incorporated with various levels of previous crop residues and/or N fertilizer. Our results imply that CH4MOD 2.0 provides a potential approach for estimating of the effects of elevated atmospheric CO2 upon CHa emissions from regional or global paddy rice fields with various management practices in a changing climate.
文摘不断升高的大气CO2浓度影响水稻颖花发育、灌浆结实和品质形成,但这种影响是否与籽粒在稻穗上的着生部位有关尚不清楚.利用稻田FACE(Free-Air CO2 Enrichment)平台,以优质丰产粳稻‘武运粳23’为材料,CO2处理设背景CO2浓度(Ambient)和高CO2浓度(增200μmol·mol^-1,FACE)两个水平,研究开放大田条件下高浓度CO2对水稻颖花密度、籽粒结实能力、稻米外观和食味品质的影响及其与稻穗不同着生位置的关系.结果表明:FACE处理使武运粳23籽粒产量平均增加18.3%,从产量构成因素看,穗数和饱粒重分别增加21.4%、9.4%,每穗颖花数、饱粒率平均减少9.0%、2.2%.FACE水稻饱粒率下降主要与稻穗不同部位空粒率大幅增加有关.FACE水稻每穗颖花数减少主要与稻穗上部、中部二次枝梗现存颖花大幅减少有关,而其他位置颖花数均无显著变化;稻穗不同位置饱粒重和饱粒率对FACE的响应无显著差异.FACE处理使绿粒率下降,但糙米长度和宽度均增加,稻穗不同部位趋势一致.FACE使垩白粒率(增幅59%)、垩白度(增幅55%)均极显著增加,增幅表现为稻穗一次枝梗>二次枝梗、上部>中部>下部.FACE使稻穗不同位置稻米直链淀粉含量略增,使最高粘度、热浆粘度、崩解值、最终粘度和消减值略降,但多未达显著水平.FACE使稻米糊化温度显著下降,弱势粒的降幅大于强势粒.综上,高浓度CO2环境下武运粳23产量增加主要与穗数增多和籽粒增重有关,而稻穗明显变小;高浓度CO2使稻米绿粒率减少,垩白增多,而对蒸煮食味品质影响较少;颖花着生位置对高浓度CO2环境下水稻颖花发育、结实和品质的影响因不同测定指标而异.
文摘To examine how the major elements of global change affect herbivory in agroecosystems, a multifactorial experiment was conducted where soybeans were grown at two levels of carbon dioxide and temperature, including those predicted for 2050, under otherwise normal field conditions. Japanese beetles (Popillia japonica Newman) were enclosed on foliage for 24 h, after which the beetle survivorship, total and per capita leaf consumption, and leaf protease inhibitor activity were measured. The direct effect of temperature on beetle consumption and survivorship also was measured under controlled environmental conditions. No differences in total foliage consumption were observed; however, beetles forced to feed at elevated temperature in the field demonstrated greater per capita consmnption and reduced survivorship compared to beetles feeding at ambient temperature. Survivorship was also greater for beetles that consumed foliage grown under elevated CO2, but there were no interactive effects of CO2 and temperature, and no differences in leaf chemistry were resolved. Leaf consumption by beetles increased strongly with increasing temperature up to -37℃, above which increased mortality caused a precipitous decrease in consumption. An empirical model based on the temperature dependence of leaf consumption and flight suggests that the 3.5℃ increase in temperature predicted for 2050 will increase the optimal feeding window for the Japanese beetle by 290%. Elevated temperature and CO2 operating independently have the potential to greatly increase foliage damage to soybean by chewing insects, such as Popilliajaponica, potentially affecting crop yields.
基金This research was supported by the National Na- tural Science Foundation of China (No. 41301209), the National Basic Research Program (973 Program) of China (No. 2014CB954500), the Natural Science Foun- dation of Jiangsu Province, China (Nos. BK20131051 and BK20140063), Project of Frontier Fields during the Thirteenth Five-Year Plan Period of the Institute of Soil Science, Chinese Academy of Sciences, and the Agricultural Science and Technology Independent In-novation Fund in Jiangsu Province, China (No. cx13- 5062). The FACE system instruments were supplied by the National Institute of Agro-Environmental Sci- ences and the Agricultural Research Center of Tohoku Region, Japan.
文摘Annual wormwood(Artemisia annua L.) is the only viable source of artemisinin,an antimalarial drug.There is a pressing need to optimize production per cultivated area of this important medicinal plant;however,the effect of increasing atmospheric carbon dioxide(CO_2) concentration on its growth is still unclear.Therefore,a pot experiment was conducted in a free-air CO2 enrichment(FACE) facility in Yangzhou City,China.Two A.annua varieties,one wild and one cultivated,were grown under ambient(374μmol mol^(-1)) and elevated(577 μmol mol^(-1)) CO_2 levels to determine the dry matter accumulation and macronutrient uptake of aerial parts.The results showed that stem and leaf yields of both A.annua varieties increased significantly under elevated CO_2 due to the enhanced photosynthesis rate.Although nitrogen(N),phosphorus(P),and potassium(K) concentrations in leaves and stems of both varieties decreased under elevated CO_2,total shoot N,P,and K uptake of the two varieties were enhanced and the ratios among the concentrations of these nutrients(N:P,N:K,and P:K) were not affected by elevated CO_2.Overall,our results provided the evidence that elevated CO_2 increased biomass and shoot macronutrient uptake of two A.annua varieties.