Prediction of the potential distribution and analysis of the freezing injury risk of winter wheat on the Loess Plateau under climate change

Determining the suitable areas for winter wheat under climate change and assessing the risk of freezing injury are crucial for the cultivation of winter wheat.We used an optimized Maximum Entropy(MaxEnt)Model to predict the potential distribution of winter wheat in the current period(1970-2020)and the future period(2021-2100)under four shared socioeconomic pathway scenarios(SSPs).We applied statistical downscaling methods to downscale future climate data,established a scientific and practical freezing injury index(FII)by considering the growth period of winter wheat,and analyzed the characteristics of abrupt changes in winter wheat freezing injury by using the Mann-Kendall(M-K)test.The results showed that the prediction accuracy AUC value of the MaxEnt Model reached 0.976.The minimum temperature in the coldest month,precipitation in the wettest season and annual precipitation were the main factors affecting the spatial distribution of winter wheat.The total suitable area of winter wheat was approximately 4.40×10^(7)ha in the current period.In the 2070s,the moderately suitable areas had the greatest increase by 9.02×10^(5)ha under SSP245 and the least increase by 6.53×10^(5)ha under SSP370.The centroid coordinates of the total suitable areas tended to move northward.The potential risks of freezing injury in the high-latitude and-altitude areas of the Loess Plateau,China increased significantly.The northern areas of Xinzhou in Shanxi Province,China suffered the most serious freezing injury,and the southern areas of the Loess Plateau suffered the least.Environmental factors such as temperature,precipitation and geographical location had important impacts on the suitable area distribution and freezing injury risk of winter wheat.In the future,greater attention should be paid to the northward boundaries of both the winter wheat planting areas and the areas of freezing injury risk to provide the early warning of freezing injury and implement corresponding management strategies.

Impacts of climate change on drought risk of winter wheat in the North China Plain

Drought is a major natural disaster causing crop yield losses,while its occurrence mechanism and spatiotemporal variations in a changing climate are still not clear.Based on a long-term climatic dataset(during 1958–2015)from weather stations in the North China Plain(NCP),the influencing mechanism of various climatic factors on drought risk of winter wheat was quantified by using sensitivity analysis,Mann-Kendall trend test and slope estimation.The results indicated that climatic factors have changed considerably over the past six decades in the growth season of winter wheat.As a result,winter wheat suffered from severe droughts(with 350 mm of water deficit during its growth season),particularly at the jointing–heading and heading–mature stages,which were critical to crop yield formation.There were large spatial and temporal variations in drought risk and climatic change factors at different growth stages of winter wheat.Despite precipitation playing a vital role in determining the spatiotemporal patterns of drought risk,high temperature and low humidity along with other climatic factors at key growth stages of winter wheat aggravated drought risk.Particularly,temperature at nearly 90%weather stations showed a notablely upward trend,which exacerbated water deficit and drought risk of winter wheat.Given the complexity and high uncertainty of climate change,these findings provide important information for adapting crop production to future climate change and accompanied droughts while ensuring food security and agricultural sustainability.

The Influence of Climate Change on Winter Wheat during 2012-2100 under A2 and A1B Scenarios in China

By assuming constant winter wheat varieties and agricultural practices in China, the influence of climate change on winter wheat is simulated using the corrected future climate projections under SRES A2 and A1B scenarios from 2012 to 2100, respectively. The results indicate that the growth of winter wheat would be strongly influenced by climate change in future. The average flowering and maturity dates of winter wheat would advance by 26 and 27 days under scenario A2, and by 23 and 24 days respectively under scenario A1B from 2012 to 2100. The simulated potential productivity of winter wheat shows a decrease of 14.3% and 12.5% for scenarios A2 and A1B respectively without the fertilization effect of CO2, while an increase of 1.3% and 0.6% with the fertilization effect of CO2. Additionally, for northern China, the simulated potential productivity would markedly decrease under both scenarios, independent with the fertilization effect of CO2, which indicates that the current planted winter wheat would be more vulnerable than that in southern China. The most likely reason is the current winter wheat varieties in northern China are winter varieties or strong winter varieties, which need some days of low temperature for dormancy. While in southern China, the winter wheat is spring or half winter varieties and can grow slowly during winter, thus, they would be affected slightly when winter temperature increases. The results of this study may have important implications for adaptation measures.

A tripole winter precipitation change pattern around the Tibetan Plateau in the late 1990s

Classical monsoon dynamics considers the winter/spring snow amount on the Tibetan Plateau(TP)as a major factor driving the East Asian summer monsoon(EASM)for its direct influence on the land-sea thermal contrast.Actually,the TP snow increased and decreased after the late 1970s and 1990s,respectively,accompanying the two major interdecadal changes in the EASM.Although studies have explored the possible mechanisms of the EASM interdecadal variations,and change in TP snow is considered as one of the major drivers,few studies have illustrated the underlying mechanisms of the interdecadal changes in the winter TP snow.This study reveals a tripole pattern of change,with decreased winter precipitation over the TP and an increase to its north and south after the late 1990s.Further analyses through numerical experiments demonstrate that the tropical Pacific SST changes in the late 1990s can robustly affect the winter TP precipitation through regulating the Walker and regional Hadley circulation.The cooling over the tropical central-eastern Pacific can enhance the Walker circulation cell over the Pacific and induce ascending motion anomalies over the Indo-Pacific region.These anomalies further drive descending motion anomalies over the TP and ascending motion anomalies to the north through regulating the regional Hadley circulation.Therefore,the positive-negative-positive winter precipitation anomalies around the TP are formed.This study improves the previously poor understanding of TP climate variation at interdecadal timescales.

Changes in wintering Hooded Cranes and their habitats at Chongming Dongtan over the past 20 years

The Hooded Crane(Grus monacha)is listed as a Vulnerable species in the IUCN red list.Tidal wetland(tideland),the major habitat for wintering Hooded Cranes at East China’s Chongming Dongtan,has dramatically changed in the past two decades,but there is limited knowledge about the population and habitat changes of the Hooded Cranes.This study investigated the population size and distribution of wintering Hooded Cranes at Chongming Dongtan from 2000 to 2021.We used remote sensing images combined with a vegetation classification algorithm to analyse the distribution of saltmarsh vegetation.The quadrat method was used to investigate the density and weight of the underground corms of Sea Bulrush(Scirpus mariquter),the main food on tideland for the Hooded Cranes.From 2000 to 2021,the population number of wintering Hooded Cranes at Chongming Dongtan remained stable at approximately 100.In 2000,the area of Scirpus spp.and Common Reed(Phragmites australis)accounted for approximately half of the total saltmarsh area at Chongming Dongtan,respectively.The invasive Smooth Cordgrass(Spartina alterniflora)rapidly expanded on tideland in the 2000s while the Scirpus spp.was competed out and thus significantly reduced in area.After the implementation of an ecological project to control Smooth Cordgrass and to restore Scirpus spp.in the 2010s,the area of the Smooth Cordgrass decreased considerably while the area of Scirpus spp.increased.The corms of Sea Bulrush decreased on the southeastern tideland during the study period,which might be the cause of the northward movement of the foraging Hooded Cranes on tideland.We also found Hooded Cranes foraged crops in the nearby farmland in mid-winter,causing human-bird conflicts in the recent decade.Our results found that changes in habitat and food conditions on tideland impacted wintering Hooded Cranes.Foraging in farmland with human disturbance in the recent decade might be related to insufficient food on tideland.We suggest active intervention to accelerate the restoration of Sea Bulrush on tideland and reduce human disturbance in farmland to improve the habitat quality of the wintering Hooded Crane at Chongming Dongtan.

Abrupt change of winter temperature over the Mongolian Plateau during 1961-2017

Studying the abrupt change of winter temperature(ACWT)over the Mongolian Plateau(MP,including Inner Mongolia Autonomous Region and State of Mongolia)is of great significance for understanding the spatiotemporal distribution of temperature and the mechanism of global climate change.Monthly temperature data during 1961–2017was collected,and the abrupt change point was determined by the Mann–Kendall test and sliding ttest,to analyze the characteristics and causes of ACWT.The results showed that(a)The winter temperature has rapidly increased with a trend of 0.41℃/10a,which was significantly higher than that of the rest area of Chinese mainland,indicating that climate change in the MP was more sensitive to global warming.(b)The abrupt change point occurred in 1988,with temperature of-15.5℃and-14.1℃before and after abrupt change,respectively.The ACWT in 50°N was 1–3 years later than that in 40°N,and the isotherms of different temperatures moved northward by 10–200 km,especially-16℃isotherms moved approximately 200 km northward after 1988.(c)The Arctic Oscillation(AO)and Mongolian High(MH)anomaly affects winter temperature over the MP.When the AO is unusually strong,the MH and East Asian winter monsoon are weak,and southerly winds prevail in most regions,which is not conducive to the cold air developing southward,leading to higher winter temperature in the MP.Overwise,abnormally northerly winds prevail and temperature is low.Meanwhile,the abrupt change time of AO occurred in 1987 before winter temperature.It shows that the AO indirectly causes winter temperatures to rise by influencing the MH and is also the main driving factor of ACWT.

被漏诊的De Winter ST-T改变1例

患者男性,68岁,主因活动后胸痛3d,加重3h于2017年10月20日急诊入院。患者近3d反复于活动后出现胸痛,为胸骨后压榨性疼痛,休息后5～10min可缓解,未至医院进一步明确诊治。就诊当日晨起于排便后再次出现胸痛,性质较前加重,伴头晕、大汗,持续不缓解,由家人送来我院急诊。既往无高血压、糖尿病等病史,吸烟30余年,5～10支/d。9月前因前列腺增生行前列腺电切术治疗。

de Winter ST-T改变心电图三例

心电图de Winter ST-T改变患者主要表现为左胸导联ST段上斜型压低和T波高尖,其左前降支血管病变严重,需行急诊冠状动脉介入治疗。本文报道三例在临床表现、心电图特征、冠状动脉造影上都符合de Winter ST-T改变心电图,临床工作中及时发现并认识这种心电现象,对指导急诊介入治疗有重要意义。

De Winter ST-T改变一例

急性心肌梗死超急性期常表现为相应导联ST抬高伴T波高耸直立,但由de Winter等于2008年首先描述了一些患者在前降支近段发生急性闭塞或次全闭塞时却可表现为胸前导联ST段上斜型压低伴T波高尖直立[1],被称为de Wniter ST-T改变,在临床上容易被误诊或漏诊,现报道一例如下：1病例简介患者男性,59岁,

对心电图de Winter ST-T改变的思考

de Winter ST-T改变心电图在命名、罪犯血管定位及诊断等方面尚有争议。本文结合文献,就de Winter ST-T改变心电图争议问题,提出了作者的观点。

老年女性患者心电图de Winter ST-T改变一例

1临床资料患者女性,66岁,因＂突发胸闷、黑矇6小时余＂入院。患者于2018-04-17下午17：00左右无明显诱因出现胸闷,伴出汗、黑矇、乏力等不适,无意识丧失、头疼、胸痛、心慌、呼吸困难、腹痛、腹泻、恶心、呕吐、发热、畏寒等症状,持续不能缓解,为求进一步诊疗,来我院急诊。患者既往体健。查体：体温36.6℃,脉搏55次/min,呼吸19次/min,血压85/54 mmHg（1 mmHg=0.133 k Pa）。

Sediment records of environmental changes in the south end of the Zhejiang-Fujian coastal mud area during the past 100 years

Previous studies carried out in the East China Sea （ECS） mud area focused on long-term environmental changes in sedimentary records during the Holoeene, especially during the mid-Holocene high-stand water levels period. These results indicate that sensitive grain size groups can be used as a sedimentary proxy to reconstruct the evolution of the East Asian Winter Monsoon （EAWM）. The studies have been carried out mainly in the northern and middle portions of the Zhejiang-Fujian coastal mud, however, similar research in the southern portion and the comparison between sedimentary proxy and modern measured data of EAWM are lacking. In this paper, we focused on a sedimentary record of the past 100 years with an enhanced resolution of 1.8 years. Investigations of the southern end of the Zhejiang-Fujian coastal mud area were conducted on the basis of 21~Pb chronology, grain-size analysis and chemical element analysis. The correspondence between the mean grain size （Mz） of sediment sensitive grain size and the measured EAWM was confirmed for the first time. We found that during the recent 100 years, the variation of the mean grain size of the sensitive population in the southern portion of the Zhejiang-Fujian mud was mainly controlled by the EAWM intensity changes; and not directly related to changes in the sediment discharge from Datong station of the Changjiang River （DTSD）. Finally, recent changes in the content of heavy metals in study area reflect the impact of human activities on the environment.

中间支闭塞致de Winter ST-T改变1例

经典的de Winter心电图改变在临床上较为少见,其梗死相关动脉多为左前降支近端。本文报道绍兴市人民医院2021年11月24日收治的1例中间支全闭致心电图de Winter ST-T改变病例,造影证实中间支100%闭塞。

Wheat Breeding Strategies under Climate Change based on CERES-Wheat Model

Climate change has inevitably had a negative impact on agricultural production and food security.Crop breeding improvement is an efficient option to adapt to future climate and increase grain production.To study the potential to provide valuable advice for breeding under climate change condition,the crop growth model was used as basis to investigate,the effects of the cultivar genotype parameters of the crop estimation through resource and environment synthesis-wheat(CERES-Wheat)model on yield under different climate scenarios.In this study,solar radiation had a positive effect on the yield of winter wheat,while the effects of daily temperature change conditions on yield were vague,particularly under a change in daily maximum temperature.For the seven cultivar genotype parameters in the CERES-Wheat model,the yield had an approximately linear increasing relationship with kernel number(G1)and kernel size(G2).Vernalization days(P1V)had a fluctuating effect on winter yield without an evident unidirectional tendency.The yield of winter wheat increased with an increase in photoperiodic response(P1D)when P1D values varied from 64.81 to 79.81.Phyllochron interval(PHINT)had a positive impact on the yield of winter wheat.This study presented the potential benefits of the crop growth model to provide directional suggestions for crop breeding.

Winter is coming for ski resorts: Insights from the Apennines (Italy)

Ski resort abandonment is more frequent due to global warming,which progressively reduces snowpack and persistence.However,projects aiming for new resorts in the Apennines have proliferated.Such economic investments are risky,especially without long-term data on snow cover duration.Our aim,thus,is to provide the first census of abandoned ski resorts in the Apennines and compare them with the resorts currently open to understand the causes that led to their abandonment.Subsequently,we explore factors behind resort failure by analyzing the relationships between climatic,geomorphological,and economic variables.Overall,we found 101 ski resorts in the Apennines,of which 28 were open,41 closed and abandoned and 32 partially closed(i.e.,closed in more than at least 7 years in the last 10 years).The closed and partially closed resorts represent 358 km of ski slopes(44%of total available).The number of structures per resort(i.e.ski lifts,chair lifts)is higher for open compared to partially closed and closed ones.Notably,the maximum elevation reached by the resorts is higher for those open(1793 m a.s.l.)than for those partially closed(1687 m a.s.l.)and especially those closed(1577 m a.s.l.).Finally,the mean size of the resorts in terms of skiable track length is larger for open(15.7 km)than partially closed(7.1 km)and closed resorts(3.2 km).The average duration of operation for abandoned resorts is 29.5 years,varying from a maximum of 56 years to a minimum of 0 years for two sites that were never opened after reconstruction.The year of abandonment is positively associated with the maximum elevation,size,and duration of operation.Furthermore,the duration of operation is negatively correlated with the construction year.Our multivariate analysis confirms and strengthens the hypothesis for the causes that lead to abandonment are multi-factorial.Most of the closed resorts are located at low altitude and have small ski areas although some higher altitude sites have also been abandoned in recent years.This information can be useful for investors,policymakers,and stakeholders who should use it as a starting point when designing and planning new resorts to avoid future failures and the loss of public money.

安徽省10-12月积温时空变化特征及冬小麦适宜播期分析

为确定安徽省冬小麦适宜播期,利用1971-2021年安徽省分布于淮北、江淮及沿江麦区的50个气象站点观测数据,分析了10-12月积温时空变化特征,并基于叶龄积温法分析了前30 a(1971-2000年)与后21 a(2001-2021年)各地冬小麦冬前生长至不同叶龄对应的播期。结果表明,1971-2021年,安徽省及其各麦区10-12月每月积温及总积温均呈显著或极显著线性增加趋势,安徽省10-12月每月积温及总积温上升速率分别为8.6、9.6、7.8和26.1℃·(10 a)^(-1),安徽省及其各麦区10-12月每月积温上升速率呈现出11月>10月>12月规律;沿江麦区12月积温上升速率[6.5℃·(10 a)^(-1)]明显低于淮北[8.4℃·(10 a)^(-1)]及江淮[8.3℃·(10 a)^(-1)]麦区;淮北和江淮麦区10-12月总积温上升速率均为26.6℃·(10 a)^(-1),沿江麦区略低[24.9℃·(10 a)^(-1)]。安徽冬小麦冬前生长至相同叶龄时,后21 a播期比前30 a总体推迟1~4 d。淮北、江淮和沿江麦区后21 a适宜播期比前30 a分别平均推迟2.61、2.86和2.07 d。后21 a淮北麦区半冬性、弱冬性品种适宜播期分别为10月16-21日、10月12-16日,江淮麦区春性、半冬性品种适宜播期分别为10月25-30日、10月21-25日,沿江麦区春性品种适宜播期为10月30日-11月4日。

不同贮藏风速下冬桃果实品质变化规律研究

为研究不同贮藏风速下冬桃果实品质的变化规律,量化风速对冬桃品质的影响,以冬桃为试验材料,研究不同风速(自然对流、0.5、1.0、1.5 m/s)下贮藏期间冬桃含水率、失重率、硬度、呼吸强度、乙烯释放量、可溶性固形物含量、可滴定酸含量和色差等指标的变化。结果表明:与自然对流相比,贮藏风速为1.0 m/s时更有利于保持冬桃果实的贮藏品质,贮藏24 d时,冬桃果实含水率为85.6%、硬度为6.79 N、可滴定酸含量为0.61%,并在降低果实呼吸强度的同时,将呼吸跃变发生的时间推迟了3 d,保持了冬桃的口感和品质。研究明确了冬桃果实在不同贮藏风速下的采后生理变化规律,为冬桃果实贮藏保鲜和品质研究提供了参考依据。

De Winter心电图改变对急性前壁心肌梗死患者病情进展的影响

目的分析de Winter心电图改变对急性前壁心肌梗死患者病情进展的影响。方法选择2017年3月至2020年3月于铜陵市人民医院心内科收治的316例急性前壁心肌梗死患者,按照患者是否存在de Winter心电图改变将其分为研究组(n=13)与对照组(n=303)。比较两组患者一般资料、分析研究组心电图特征及心电图与病情进展的关系。结果研究组患者年龄、左心室射血指数低于对照组,冠状动脉粥样硬化性心脏病(冠心病)家族史、三酰甘油、血清氯水平高于对照组(P<0.05)。研究组所有患者为窦性心律,QRS波时限、PR间期、QTc间期、心率正常,症状发生后首次出现de Winter心电图平均时间为107 min。De Winter心电图改变发展为STEMI心电图占69.23%,de Winter心电图改变发展为STEMI心电图的平均时间113 min。13例de Winter心电图改变患者V_(1)导联正常,而V_(2)~V_(6)导联出现J点后ST段压低,伴正向高大对称的T波改变;V_(3)~V_(5)导联均存在ST压低,最压低为V_(3)导联;V_(2)~V_(6)导联均存在高大直立T波,V_(3)导联T波最高;还发现当患者出现de Winter心电图改变时,后壁、右室导联ST段、T波正常或ST段、T波轻度压低,倒置,且行治疗后ST段均回至基线;随病情发展,9例患者胸前导联可在短时间内由de Winter心电图改变发展为ST段抬高或病理性Q波、R波递增不良、T波倒置形成的急性前壁STEMI心电图,以V_(1)~V_(4)导联主表现;4例患者胸前导联de Winter心电图改变发展为R波递增不良。结论De Winter心电图改变可发展为ST段抬高、形成病理Q波、R波不良递增,是出现早期急性STEMI的心肌缺血的表现。

Recent Progress in Studies of the Variabilities and Mechanisms of the East Asian Monsoon in a Changing Climate

Located in a monsoon domain,East Asia suffers devastating natural hazards induced by anomalous monsoon behaviors.East Asian monsoon(EAM)research has traditionally been a high priority for the Chinese climate community and is particularly challenging in a changing climate where the global mean temperature has been rising.Recent advances in studies of the variabilities and mechanisms of the EAM are reviewed in this paper,focusing on the interannual to interdecadal time scales.Some new results have been achieved in understanding the behaviors of the EAM,such as the evolution of the East Asian summer monsoon(EASM),including both its onset and withdrawal over the South China Sea,the changes in the northern boundary activity of the EASM,or the transitional climate zone in East Asia,and the cycle of the EASM and the East Asian winter monsoon and their linkages.In addition,understanding of the mechanism of the EAM variability has improved in several aspects,including the impacts of different types of ENSO on the EAM,the impacts from the Indian Ocean and Atlantic Ocean,and the roles of mid-to high-latitude processes.Finally,some scientific issues regarding our understanding of the EAM are proposed for future investigation.

1981~2021年南水北调中线工程安阳河以北段冬季冷暖变化特征分析

为更好地开展南水北调中线工程冰期输水调度,基于中线工程沿线8个国家气象站点的1981~2021年冬季日平均气温数据,采用气候平均值、气候倾向率等统计方法,并依据国家冷暖冬等级划分标准,在年度尺度上,对安阳河以北段近41 a来冬季冷暖变化气候特征进行了统计分析。结果表明:①1981~2021年,各站冬季平均气温基本为-5~3℃,在空间上整体呈现南高北低的特征,南北温差基本为3~4℃。②1981~2021年,各站冬季平均气温年际变化规律基本一致,整体上均呈现出波动上升的趋势,增温幅度为0.113~0.713℃/(10 a),整体表现为南北升温速率低,中部升温速率高的特点。③从年代际变化来看,1980年代各站冬季平均气温最低,多为偏冷年份,整体上1980,1990和2010年代表现为升温趋势,2010年代升温最为显著,而2000年代则表现为降温趋势。其中,在2000年代和2010年代,各站冬季平均气温波动频繁,且幅度较大,平均气温标准差均超过了1.0℃。④近41 a区域暖冬年共出现12次,主要在1990年代中期以后,区域冷冬年共出现18次,其中,1980年代最多,1990年代最少,自1990年代末期开始,区域冷冬年、暖冬年时常交替出现,而在2014年后,区域暖冬年明显偏多。研究成果可为南水北调中线工程优化冰期输水调度、提升冬季渠道过流能力提供参考。