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1.
M. Van Oijen † A. H. C. M. Schapendonk † M. J. H. Jansen † C. S. Pot† R. Maciorowski‡ 《Global Change Biology》1999,5(4):411-421
The microclimate in facilities for studying effects of elevated CO2 on crops differs from ambient conditions. Open-top chambers (OTCs) increase temperature by 1–3 °C. If temperature and CO2 interact in their effect on crops, this would limit the value of OTC experiments. Furthermore, interaction of CO2 and temperature deserves study because increases in atmospheric CO2 concentration are expected to cause global warming. This paper describes two experiments in which a recently developed cooling system for OTCs was used to analyse the effects of temperature on photosynthesis, growth and yield of spring wheat (Triticum aestivum L., cv. Minaret). Two levels of CO2 were used (350 and 700 ppm), and two levels of temperature, with cooled OTCs being 1.6–2.4 °C colder than noncooled OTCs. Photosynthetic rates were increased by elevated CO2, but no effect of temperature was found. Cross-switching CO2 concentrations as well as determination of A–Ci curves showed that plant photosynthetic capacity after anthesis acclimated to elevated CO2. The acclimation may be related to the effects of CO2 on tissue composition: elevated CO2 decreased leaf nitrogen concentrations and increased sugar content. Calculations of the seasonal mean crop light-use efficiency (LUE) were consistent with the photosynthesis data in that CO2 increased LUE by 20% on average whereas temperature had no effect. Both elevating CO2 and cooling increased grain yield, by an average of 11% and 23%, respectively. CO2 and temperature stimulated yield via different mechanisms: CO2 increased photosynthetic rate, but decreased crop light interception capacity (LAI), whereas cooling increased grain yield by increasing LAI and extending the growing season with 10 days. The effects of CO2 and temperature were not additive: the CO2 effect was about doubled in the noncooled open-top chambers. In most cases, effects on yield were mediated through increased grain density rather than increased individual grain weights. The higher growth response to elevated CO2 in noncooled vs. cooled OTCs shows that a cooling system may remove a bias towards overestimating crop growth response to CO2 in open-top chambers. 相似文献
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《植物生态学报》2017,41(10):1060
Aims Global warming is expected to be the strongest in high altitude mountainous areas, which are more ecologically fragile and economically marginalized. The Qinghai-Xizang Plateau is among such areas most vulnerable to global warming, and more than 80% of its population depends on subsistence agriculture. The aim of this study is to understand the impacts of warming on indigenous crop production, which can help to devise better strategies for crop adaptation and food security in this area.Methods A field warming experiment using a facility of free air temperature increase was conducted to simulate the predicted warming level in Caigongtang town, Lhasa City, China. The experiment consisting of two treatments (warmed and non-warmed) was performed using a completely random design with three replicates. An infrared heater (180 cm in length and 20 cm in width) of 1 500 W was suspended 1.5 m above the ground in each warmed plot. In each non-warmed plot, a ‘dummy’ heater of same dimensions was also suspended to mimic the shading effects. The warming treatment was performed from the sown date to the harvest date. We measured dry matter and nitrogen accumulation, partition and translocation of winter wheat (Triticum aestivum) using ‘Shandong 6’ under warming and control treatments.Important findings Results showed that, with 1.1 °C increase in daily mean air temperature during winter wheat growing season, the dry matter accumulation rate at population level from sowing to anthesis stage, grain dry matter partition ratio and contribution of dry matter translocation amount to grain after anthesis were 27.5%, 5.6% and 68.6% higher, respectively, in the warmed plots than those in the non-warmed plots. Meanwhile, warming increased nitrogen accumulation rate at population level of winter wheat. Nitrogen distribution proportions in grain and nitrogen translocation efficiency from vegetative organs to grain after anthesis in the warmed treatment were 6.0% and 5.5% higher than those in the non-warmed treatment, respectively. Compared with non-warmed treatment, warming decreased harvest index by 3.1%, though the difference was not statistically significant. Grain yield, nitrogen uptake efficiency, nitrogen partial factor productivity and nitrogen harvest index were 8.1%, 20.8%, 8.1% and 6.0% higher, respectively, in the warmed plots than those in the non-warmed plots. In conclusion, an increase in daily mean air temperature of about 1.1 °C can enhance plant growth during the pre-anthesis phase by mitigating the low temperature limitation, and accelerate dry matter and nitrogen partition and translocation to the grain after anthesis in winter wheat. These results suggest that warming may benefit winter wheat production through increasing nitrogen use efficiency in high altitude areas. 相似文献
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近40a来,宁夏引黄灌区年平均增温幅度高于全国平均值,对春小麦生产已经产生了重大影响。基于哥本哈根联合国气候变化大会控制未来50 a全球升温幅度的范围值,设计增温幅度为0.5-2.5 ℃,采用红外线辐射器大田增温模拟实验,研究增温对宁夏引黄灌区春小麦生长发育和产量的影响。结果表明:增温0.5-2.5 ℃,宁夏引黄灌区春小麦全生育期(播种-收获)缩短1-22 d,减产0.5%-18.5%;增温2.0-2.5 ℃,春小麦全生育期缩短18-22 d,减产16.5%-18.5%。增温引起春小麦三叶期和孕穗期光合速率下降,穗粒数减少,千粒重下降,最终导致减产。 相似文献
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The transformation of climatic regime has an undeniable impact on plant production, but we rarely have long enough date series to examine the unfolding of such effects. The clarification of the relationship between crop plants and climate has a near‐immediate importance due to the impending human‐made global change. This study investigated the relationship between temperature, precipitation, drought intensity and the yields of four major cereals in Hungary between 1921 and 2010. The analysis of 30‐year segments indicated a monotonously increasing negative impact of temperature on crop yields. A 1°C temperature increase reduced the yield of the four main cereals by 9.6%–14.8% in 1981–2010, which revealed the vulnerability of Eastern European crop farming to recent climate change. Climate accounted for 17%–39% of yield variability over the past 90 years, but this figure reached 33%–67% between 1981 and 2010. Our analysis supports the claim that the mid‐20th century green revolution improved yields “at the mercy of the weather”: during this period, the impact of increasing fertilization and mechanisation coincided with climatic conditions that were more favourable than today. Crop yields in Eastern Europe have been stagnating or decreasing since the mid‐1980s. Although usually attributed to the large socio‐economic changes sweeping the region, our analysis indicates that a warming climate is at least partially responsible for this trend. Such a robust impact of increasing temperatures on crop yields also constitutes an obvious warning for this core grain‐growing region of the world. 相似文献
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播期对春小麦生长发育及产量的影响 总被引：8，自引：0，他引：8
为了给陇中半干旱区春小麦高产栽培提供依据,2010年在甘肃定西进行了春小麦分期播种试验,并对不同播期条件下春小麦生长发育及产量形成进行了分析。结果表明:随着播期的推迟,春小麦播种-抽穗期日数减少、全生育期明显缩短;5月下旬之前,越早播种的春小麦LAI越大,5月下旬之后,播种愈晚春小麦LAI越大。早播春小麦LAI峰值靠前,晚播峰值滞后;6月下旬之前,播期早的春小麦叶绿素含量高于播期晚的,6月下旬之后播期愈早叶绿素含量下降愈快;不同播期春小麦群体生长率和净同化率在孕穗-抽穗期后差异显著,表现为3月18日播期最大,4月7日播期最小。各播期干物质累积在拔节期后表现为快速递增趋势。在拔节期前,早播处理的干物质积累速率较慢。随着播期的推迟,单株干物质最大积累速率出现时间提前,籽粒最大灌浆速率出现时间推迟,千粒重表现为先升后降;灌浆3个阶段各参数受播期影响比较显著;早播春小麦产量最高。 相似文献
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开放式增温下非对称性增温对冬小麦生长特征及产量构成的影响 总被引：14，自引：0，他引：14
在江苏南京(2007-2009年)设置了全天增温(AW)、白天增温(DW)和夜间增温(NW)3种处理,研究冬小麦生长及产量构成的响应差异.结果表明:非对称性增温条件下,冬小麦的无效分蘖减少,有效分蘖增加.对照(CK)处理的无效分蘖分别是AW、DW和NW处理的2.6、1.7和3.5倍,但有效分蘖却比3个增温处理分别减少13.7%、3.2%和0.5%.AW、DW和NW处理小麦株高分别较CK提高了5.6%、4.5%和1.3%.旗叶面积分别提高了45.7%、39.4%和26.1%,开花期总绿叶面积分别提高了25.1%、29.8%和17.3%,同期绿叶比分别提高了37.7%、43.3%和38.7%.穗部性状中,AW、DW和NW处理的每穗颖花数平均比CK提高了4.1%、5.7%和1.7%,每穗实粒数分别提高了2.2%、5.3%和2.6%.AW、DW和NW处理冬小麦的粒叶比平均分别较CK降低了15.3%、8.5%和11.3%,但千粒重平均分别提高了6.9%、6.2%和11.8%,单位面积产量平均分别提高了27.0%、40.1%和18.3%.表明预期增温条件下华东地区冬小麦生产力将可能进一步提高. 相似文献
8.
Zhisheng Yao;Haojie Guo;Yan Wang;Yang Zhan;Tianli Zhang;Rui Wang;Xunhua Zheng;Klaus Butterbach-Bahl; 《Global Change Biology》2024,30(2):e17177
Maintaining or even increasing crop yields while reducing nitrous oxide (N2O) emissions is necessary to reconcile food security and climate change, while the metric of yield-scaled N2O emission (i.e., N2O emissions per unit of crop yield) is at present poorly understood. Here we conducted a global meta-analysis with more than 6000 observations to explore the variation patterns and controlling factors of yield-scaled N2O emissions for maize, wheat and rice and associated potential mitigation options. Our results showed that the average yield-scaled N2O emissions across all available data followed the order wheat (322 g N Mg−1, with the 95% confidence interval [CI]: 301–346) > maize (211 g N Mg−1, CI: 198–225) > rice (153 g N Mg−1, CI: 144–163). Yield-scaled N2O emissions for individual crops were generally higher in tropical or subtropical zones than in temperate zones, and also showed a trend towards lower intensities from low to high latitudes. This global variation was better explained by climatic and edaphic factors than by N fertilizer management, while their combined effect predicted more than 70% of the variance. Furthermore, our analysis showed a significant decrease in yield-scaled N2O emissions with increasing N use efficiency or in N2O emissions for production systems with cereal yields >10 Mg ha−1 (maize), 6.6 Mg ha−1 (wheat) or 6.8 Mg ha−1 (rice), respectively. This highlights that N use efficiency indicators can be used as valuable proxies for reconciling trade-offs between crop production and N2O mitigation. For all three major staple crops, reducing N fertilization by up to 30%, optimizing the timing and placement of fertilizer application or using enhanced-efficiency N fertilizers significantly reduced yield-scaled N2O emissions at similar or even higher cereal yields. Our data-driven assessment provides some key guidance for developing effective and targeted mitigation and adaptation strategies for the sustainable intensification of cereal production. 相似文献
9.
Xing Xu Hanming Yuan Shuhua Li Richard Trethowan Philippe Monneveux 《植物学报(英文版)》2007,49(10):1497-1507
In C3 plants, carbon isotope discrimination (Δ) has been proposed as an indirect selection criterion for grain yield. Reported correlations between Δ and grain yield however, differ highly according to the analyzed organ or tissue, the stage of sampling, and the environment and water regime. In a first experiment carried out in spring wheat during two consecutive seasons in the dry conditions of northwest Mexico (Ciudad Obregon, Sonora), different water treatments were applied, corresponding to the main water regimes available to spring wheat worldwide, and the relationships between Δ values of different organs and grain yield were examined. Under terminal (post‐anthesis) water stress, grain yield was positively associated with Δ in grain at maturity and in leaf at anthesis, confirming results previously obtained under Mediterranean environments. Under early (pre‐anthesis) water stress and residual moisture stress, the association between grain Δ and yield was weaker and highly depended on the quantity of water stored in the soil at sowing. No correlation was found between Δ and grain yield under optimal irrigation. The relationship between Δ and grain yield was also studied during two consecutive seasons in 20 bread wheat cultivars in the Ningxia region (Northern China), characterized by winter drought (pre‐anthesis water stress). Wheat was grown under rainfed conditions in two locations (Guyuan and Pengyang) and under irrigated conditions in another two (Yinchuan and Huinong). In Huinong, the crop was also exposed to salt stress. Highly significant positive associations were found between leaf and grain Δ and grain yields across the environments. The relationship between Δ and yield within environments highly depended on the quantity of water stored in the soil at sowing, the quantity and distribution of rainfall during the growth cycle, the presence of salt in the soil, and the occurrence of irrigation before anthesis. These two experiments confirmed the value of Δ as an indirect selection criterion for yield and a phenotyping tool under post‐anthesis water stress (including limited irrigation). 相似文献
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Gina Mills Katrina Sharps David Simpson Håkan Pleijel Malin Broberg Johan Uddling Fernando Jaramillo William J Davies Frank Dentener Maurits Van den Berg Madhoolika Agrawal Shahibhushan B. Agrawal Elizabeth A. Ainsworth Patrick Büker Lisa Emberson Zhaozhong Feng Harry Harmens Felicity Hayes Kazuhiko Kobayashi Elena Paoletti Rita Van Dingenen 《Global Change Biology》2018,24(8):3560-3574
Introduction of high‐performing crop cultivars and crop/soil water management practices that increase the stomatal uptake of carbon dioxide and photosynthesis will be instrumental in realizing the United Nations Sustainable Development Goal (SDG) of achieving food security. To date, however, global assessments of how to increase crop yield have failed to consider the negative effects of tropospheric ozone, a gaseous pollutant that enters the leaf stomatal pores of plants along with carbon dioxide, and is increasing in concentration globally, particularly in rapidly developing countries. Earlier studies have simply estimated that the largest effects are in the areas with the highest ozone concentrations. Using a modelling method that accounts for the effects of soil moisture deficit and meteorological factors on the stomatal uptake of ozone, we show for the first time that ozone impacts on wheat yield are particularly large in humid rain‐fed and irrigated areas of major wheat‐producing countries (e.g. United States, France, India, China and Russia). Averaged over 2010–2012, we estimate that ozone reduces wheat yields by a mean 9.9% in the northern hemisphere and 6.2% in the southern hemisphere, corresponding to some 85 Tg (million tonnes) of lost grain. Total production losses in developing countries receiving Official Development Assistance are 50% higher than those in developed countries, potentially reducing the possibility of achieving UN SDG2. Crucially, our analysis shows that ozone could reduce the potential yield benefits of increasing irrigation usage in response to climate change because added irrigation increases the uptake and subsequent negative effects of the pollutant. We show that mitigation of air pollution in a changing climate could play a vital role in achieving the above‐mentioned UN SDG, while also contributing to other SDGs related to human health and well‐being, ecosystems and climate change. 相似文献
13.
麦套春棉土壤温度动态变化的研究孙本普张宝民王勇李秀云毛允峰（山东省滨州地区农业科学研究所,２５６６１５）刘桂珍张仁峰朱洪森宋新（山东省邹平县长山镇农技站,２５６２０６）ＳｔｕｄｉｅｓｏｆｄｙｎａｍｉｃＣｈａｎｇｅｏｆＳｏｉｌＴｅｍｐｅｒａｔｕｒｅｉｎ... 相似文献
14.
利用McCree(1986)测定整株植物碳平衡的方法,研究了半干旱区3个春小麦品种的籽实产量、根量、根冠比与碳平衡的关系。结果表明在开花期地方品种和尚头较之现代品种有更大的根量和根冠比。同一品种不同水分条件下根和茎叶CO2交换率(CER)波动幅度与水分条件正相关;在相同水分条件下不同品种间,品种和尚头波动幅度最大,品种定西-24次之,品种陇春-8139最小。从根和茎叶呼吸及日净碳获得量随水分供给条件的变化来看,品种和尚头和品种定西-24与品种陇春-8139相比在资源获取器官上存在着生长冗余,而且这种冗余也表现在生理代谢上,随水分条件的改善而增加。说明大根系品种在根系上存在着冗余,减少根系冗余可望成为半干旱区小麦高产育种的一条有效途径。 相似文献
15.
A conceptual framework is developed and used for improving the livelihood of Sub-Saharan communities faced with multiple stresses
resulting from adverse environments, vector-transmitted diseases, and limited food. Ecosocial systems are the units for management.
The accumulation of ecological, economic, and social capital is the objective of management, the reduction of maintenance
costs is the key strategy, and technologies must satisfy ecological, economic, and social criteria. Interacting social system
components are communities, facilitators, scientists, and political as well as administrative organizations. An adaptive approach
to management allows flexibility in human and financial resource allocation and results in changes in knowledge and efficacy
of management operations. The implementation strategy at two sites in Ethiopia relies on a two-stage procedure. In Stage 1,
human and cattle health management set the conditions for development. In Stage 2, the ecosocial system is kept on a trajectory
to enhanced ecological, economic, and social capital. In each stage, the assignment of responsibilities leads to four implementation
phases. In Stage 1, successful precision targeting of tsetse and drug-based Trypanosoma spp. control increased the economic and social capital at the Luke site in southwestern Ethiopia but threatened the ecological
capital because of overstocking and land degradation. In Stage 2, a women’s group living in the outskirts of Addis Ababa (Ethiopia)
transformed barren land into a horticultural enterprise to enhance ecosystem service provision, including production of horticultural
goods, and increase soil fertility expressed by nutrients and water availability. This article reviews concepts on human livelihood
improvement in Sub-Saharan Africa and identifies principles that became important during project execution. 相似文献
16.
用盆栽方法测定了2个春小麦品种－地方品种和尚头与现代品种陇春－8275在5个土壤水分梯度下,单、混播时的水分消耗、水分利用效率、竞争能力和籽实产量。单播条件下,在极低水分条件下（12％）,和尚头有相对较高的产量,在水分条件较好时陇春－8275有较高的产量;在保持各水分处理条件下,地方品种和尚头较之现代品种陇春－8275消耗更多的水分,水分利用效率较低。混播条件下,各尚头有较高生物量、籽实产量及较强的竞争能力,竞争优势不受土壤水分的影响,其表现为高个体生物量品种较之低个体生物量品种消耗更多的水分,陇春－8275受到强烈的抑制,消耗较少的水分及较低的籽实产量。表明进化选择的是竞争能力,而非单播下的产量表现。可以预见,在小麦育种中选育具小根系的对水分弱竞争能力的品种将成为半干旱区今后育种的一个重要方法。 相似文献
17.
黄浦江上游主要树种水源涵养林生态系统碳储量 总被引：1，自引：0，他引：1
研究林分碳储量对了解一个地区森林生态系统服务功能和碳汇林分经营具有重要意义。本研究以上海黄浦江上游水源涵养林杜英、香樟、马褂木和黄山栾树等4个主要树种为对象,构建了4个树种林木生物量方程,并对4个树种林分生物量(乔木层、凋落物层)碳储量和土壤碳储量进行了估测。结果表明,4个树种的胸径-生物量方程拟合效果较好(R2>0.9)。9年生人工林生态系统总碳储量分别为杜英117.32t·hm-2、香樟127.38t·hm-2、黄山栾树80.93t·hm-2、马褂木105.87t·hm-2。在杜英、香樟、黄山栾树和马褂木林总碳储量中,乔木层碳储量所占比例分别为35.1%、44.6%、35.2%和19.0%,凋落物层碳储量所占比例分别为1.2%、1.9%、1.2%和0.6%,土壤碳储量(0～40cm)所占比例分别为63.7%、53.5%、63.6%和80.4%。这些人工幼龄林现在处于快速生长阶段,具有较高的固碳潜力。 相似文献
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通过两年室外盆栽和室内人工控制试验,建立了不同冬春性小麦品种死苗率与低温的定量关系,确定了隆冬期不同冬春性小麦品种死苗率达10%、20%和50%的临界低温以及抗冻能力密度.结果表明： 强冬性小麦品种抗冻能力最强,半致死温度最低（燕大1817为-21.5 ℃,京411为-21.2 ℃）,其次是冬性品种（农大211为-21.1 ℃,农大5363为-20.3 ℃）和弱冬性品种（郑366为-18.5 ℃,平安8号为-18.4 ℃）,春性品种抗冻能力最弱（郑9023为-15.4 ℃,偃展4110为-14.7 ℃）.当温度降低到冬小麦冻害发生临界温度后,温度每降低1 ℃,弱冬性小麦（郑366和平安8号）死苗率增量最大,分别增加16.8%和25.8%,冬性小麦（农大211和农大5363）死苗率分别增加14.7%和18.9%,强冬性小麦（燕大1817和京411）死苗率分别增加15.4%和13.1%,春性小麦（郑9023和偃展4110）死苗率分别增加13.8%和15.1%,说明冻害发生后若持续降温,弱冬性品种遭受冻害风险更大. 相似文献
19.
Ingunn M. Tombre Thomas Oudman Paul Shimmings Larry Griffin Jouke Prop 《Global Change Biology》2019,25(11):3680-3693
All long‐distance migrants must cope with changing environments, but species differ greatly in how they do so. In some species, individuals might be able to adjust by learning from individual experiences and by copying others. This could greatly speed up the process of adjustment, but evidence from the wild is scarce. Here, we investigated the processes by which a rapidly growing population of barnacle geese (Branta leucopsis) responded to strong environmental changes on spring‐staging areas in Norway. One area, Helgeland, has been the traditional site. Since the mid‐1990s, an increasing number of geese stage in another area 250 km further north, Vesterålen. We collected data on goose numbers and weather conditions from 1975 to 2017 to explore the extent to which the increase in population size and a warmer climate contributed to this change in staging area use. During the study period, the estimated onset of grass growth advanced on average by 0.54 days/year in each of the two areas. The total production of digestible biomass for barnacle geese during the staging period increased in Vesterålen but remained stable in Helgeland. The goose population has doubled in size during the past 25 years, with most of the growth being accommodated in Vesterålen. The observations suggest that this dramatic increase would not have happened without higher temperatures in Vesterålen. Records of individually marked geese indicate that from the initial years of colonization onwards, especially young geese tended to switch to Vesterålen, thereby predominating in the flocks at Vesterålen. Older birds had a lower probability of switching to Vesterålen, but over the years, the probability increased for all ages. Our findings suggest that barnacle geese integrate socially learned behaviour with adjustments to individual experiences, allowing the population to respond rapidly and accurately to global change. 相似文献