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Spring Festival Boom Propels Concerted Consumption
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作者 Zhang Hui 《China Today》 2024年第3期2-2,共1页
The 474 million trips-raking in RMB 632.69 billion of tourism-related revenue-during the eight-day Spring Festival holiday indisputably signifies both the vitality of China’s economy and the huge potential of the cou... The 474 million trips-raking in RMB 632.69 billion of tourism-related revenue-during the eight-day Spring Festival holiday indisputably signifies both the vitality of China’s economy and the huge potential of the country’s domestic consumption.The figures respectively represent a 19 percent increase and a 7.7 percent growth over those for the same holiday period,prior to the COVID-19 pandemic,in 2019,according to data released by the country’s Ministry of Culture and Tourism on February 18. 展开更多
关键词 spring tripS HOLIDAY
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Contribution of Global Warming and Atmospheric Circulation to the Hottest Spring in Eastern China in 2018 被引量:3
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作者 Chunhui LU Ying SUN +1 位作者 Nikolaos CHRISTIDIS Peter ASTOTT 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2020年第11期1285-1294,共10页
The spring of 2018 was the hottest on record since 1951 over eastern China based on station observations,being 2.5°C higher than the 1961−90 mean and with more than 900 stations reaching the record spring mean te... The spring of 2018 was the hottest on record since 1951 over eastern China based on station observations,being 2.5°C higher than the 1961−90 mean and with more than 900 stations reaching the record spring mean temperature.This event exerted serious impacts in the region on agriculture,plant phenology,electricity transmission systems,and human health.In this paper,the contributions of human-induced climate change and anomalous anticyclonic circulation to this event are investigated using the newly homogenized observations and updated Met Office Hadley Centre system for attribution of extreme events,as well as CanESM2(Second Generation Canadian Earth System Model)simulations.Results indicate that both anthropogenic influences and anomalous anticyclonic circulation played significant roles in increasing the probability of the 2018 hottest spring.Quantitative estimates of the probability ratio show that anthropogenic forcing may have increased the chance of this event by ten-fold,while the anomalous circulation increased it by approximately two-fold.The persistent anomalous anticyclonic circulation located on the north side of China blocked the air with lower temperature from high latitudes into eastern China.Without anthropogenic forcing or without the anomalous circulation in northern China,the occurrence probability of the extreme warm spring is significantly reduced. 展开更多
关键词 extreme warm spring extreme event attribution anthropogenic influence circulation effect
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Changes in Mixed Layer Depth and Spring Bloom in the Kuroshio Extension under Global Warming 被引量:1
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作者 Ruosi ZHANG Shang-Ping XIE +1 位作者 Lixiao XU Qinyu LIU 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2016年第4期452-461,共10页
The mixed layer is deep in January-April in the Kuroshio Extension region. This paper investigates the response in this region of mixed layer depth (MLD) and the spring bloom initiation to global warming using the o... The mixed layer is deep in January-April in the Kuroshio Extension region. This paper investigates the response in this region of mixed layer depth (MLD) and the spring bloom initiation to global warming using the output of 15 models from CMIP5. The models indicate that in the late 21st century the mixed layer will shoal and the MLD reduction will be most pronounced in spring at about 33~N on the southern edge of the present deep-MLD region. The advection of temperature change in the upper 100 m by the mean eastward flow explains the spatial pattern of MLD shoaling in the models. Associated with the shoaling mixed layer, the onset of spring bloom inception is projected to advance due to the strengthened stratification in the warming climate. 展开更多
关键词 mixed layer depth global warming temperature advection spring bloom
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Analysis of a Tropical Warm Spring Microbiota Using 16S rRNA Metabarcoding
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作者 Deborah Fasesan Karim Dawkins +4 位作者 Roberto Ramirez Hadiza Rasheed-Jada Abiodun Onilude Oyekanmi Nash Nwadiuto Esiobu 《Advances in Microbiology》 2020年第4期145-165,共21页
The Ikogosi Warm Spring is a unique ecological niche in Western Nigeria with an average temperature and pH of 38°C and 5.8 respectively. It mixes with an adjacent cold spring (28°C & pH 7.6), about 100 m... The Ikogosi Warm Spring is a unique ecological niche in Western Nigeria with an average temperature and pH of 38°C and 5.8 respectively. It mixes with an adjacent cold spring (28°C & pH 7.6), about 100 meters from source, yielding a confluence body of water of 32°C and pH 7.7. To explore the bacterial community structure of this uncommon environment and to scan for potentially useful bacteria, metagenomes extracted directly from five samples (source and mid-point of warm spring;source and midpoint of cold spring, and the confluence) were analyzed. Using the MiSeq Illumina next generation sequencing protocols, the V3-V4 region of the 16S rRNA gene pool was sequenced and analyzed by QIIME (Quantitative Insights into Microbial Ecology) and R software. At least 11% (47,446) of all the sequences were unknown to any of the databases employed. Bacterial diversity and abundance at the source of both springs were extremely low, accounting for less than 0.07% of the total sequence reads at the confluence, 100 m downstream. In contrast to the highly diversified mesophilic confluence community where 21 different phyla were identified, only 4 and 5 phyla were recovered from the source-point of the warm spring and cold spring respectively. The most prevalent phyla in all samples were members of the versatile Proteobacteria (35% - 50% relative abundance), and the hardy Firmicutes (33% - 40%). Operational taxonomic units (OTUs) obtained from all the samples averaged at 1414. Temperature and pH were equally significant predictors of genomic diversity and richness, with the warm and cold spring sources having less than 5 bacteria phyla. Exiguobacterium sp. (a potential plastic degrader) and other deep rooted bacteria were found in the warm spring while the cold spring outflow contained among others such as Rubrobacter sp. and Chloroflexi sp. (which is close to the phylogenetic root of the domain Bacteria). Many taxonomically unresolved sequences could indicate the presence of potentially novel bacteria in this unique body of water and underscores the need to systematically mine these rare genetic reservoirs for biotechnological applications. Moreover, such tropical hydrothermal ecosystems could contain some unknown primitive bacteria at the origins of life. 展开更多
关键词 Ikogosi warm springS AMPLICON METAGENOMICS Next-Gen Sequencing QIIME Bacterial Diversity Source
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Influence of the Eastern Indian Ocean Warm Pool Variability on the Spring Precipitation in China
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作者 YANG Yuxing HUANG Fei 《Journal of Ocean University of China》 SCIE CAS 2005年第4期403-410,共8页
The relationship between the variability of the Eastern India Ocean Warm Pool (EIWP) and the spring precipitation in China is studied in the paper based on an analysis of the Simple Ocean Data Assimilation (SODA) Sea ... The relationship between the variability of the Eastern India Ocean Warm Pool (EIWP) and the spring precipitation in China is studied in the paper based on an analysis of the Simple Ocean Data Assimilation (SODA) Sea Surface Temperature (SST) data, the reanalysis data of monthly grid wind field at 925 hPa with a resolution of 2.5° latitude and longitude from the National Center for Environmental Prediction/National Center for Atmospheric Research (NCEP/NCAR),and the monthly mean rainfall data from 160 observational stations in China. The results show that there is a strong correlation between the EIWP variability and the spring precipitation in China. The area, volume and intensity indices of the EIWP are negatively correlated with the spring precipitation in southwestern China, while they are positively correlated with the spring precipitation in the rest of China, especially in the northeast. For this correlation between the EIWP variability and the spring precipitation in China, it is found that the correlative relationship is mainly connected with the variations of the moisture transport by the warm air flow, which is under the influence of the EIWP variability, into the inland of China in spring. Two causative factors may influence this transport. One is the variation of the moisture transport carried by the warm air flow from the Arabian Sea influenced by the EIWP variability. The other is the variation of the equator-crossing flow (70°-90°E) influenced by the EIWP anomaly in the previous winter which exerts its effect on the moist warm air transported from the Southern Hemisphere. The position and intensity of the Western North Pacific Subtropical High (WNPSH)variability caused by EIWP variation also influence the spring precipitation in China. 展开更多
关键词 the Eastern Indian Ocean warm pool spring precipitation
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暖冬及倒春寒天气对平欧杂种榛的影响及对策
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作者 孙万河 《北方果树》 2024年第3期43-45,共3页
平欧大榛子在我国栽培历史较短,由于品种多,栽培地域广泛,各地气候、土壤条件差异较大,加上种植者对各品种特性了解不足,生产上出现了各种各样的问题。该文就暖冬及倒春寒天气对平欧大榛子影响情况进行调查,并分析原因、提出应对的解决... 平欧大榛子在我国栽培历史较短,由于品种多,栽培地域广泛,各地气候、土壤条件差异较大,加上种植者对各品种特性了解不足,生产上出现了各种各样的问题。该文就暖冬及倒春寒天气对平欧大榛子影响情况进行调查,并分析原因、提出应对的解决措施,希望能为种植户及拟发展该产业者提供帮助。 展开更多
关键词 平欧大榛子 暖冬 倒春寒 品种 管理
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高强度TRIP-SH钢在汽车前梁构件中回弹问题的研究 被引量:1
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作者 苏钰 张梅 +1 位作者 符仁钰 李麟 《上海金属》 CAS 2008年第4期12-15,共4页
通过结构分析和CAE模拟对高强度TRIP-SH钢在汽车前梁构件中的回弹问题进行研究,利用在模具局部位置增加沟槽和零件局部位置设置工艺面来释放应力、改变应力状态以达到减小回弹的目的,零件的冲压成形试验证明模拟分析与试验结果相符。
关键词 trip 回弹 计算机辅助模拟分析
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气候变化背景下青海省春小麦水分盈亏率时空分布特征
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作者 郭守生 张铖玉 +2 位作者 马昕芮 赵梦凡 雷春凯 《中国农学通报》 2024年第20期122-129,共8页
本研究旨在科学评价青海省春小麦种植区农业气候变化情况,并合理利用降水资源。采用线性倾向估计、突变检验、空间插值等方法,分析了1991—2021年青海省春小麦生育期气候要素变化趋势及水分盈亏率时空变化特征,并用通径法分析各气象要... 本研究旨在科学评价青海省春小麦种植区农业气候变化情况,并合理利用降水资源。采用线性倾向估计、突变检验、空间插值等方法,分析了1991—2021年青海省春小麦生育期气候要素变化趋势及水分盈亏率时空变化特征,并用通径法分析各气象要素与春小麦水分盈亏率的关系。结果表明:青海省春小麦生长期间,气温、≥0℃积温、降水量分别以0.3℃/10 a、50.7℃/10 a、23.6 mm/10 a的速率极显著上升,日照时数以66.6 h/10 a的速率极显著下降,各生育阶段变化趋势显著性不同;全生育期、茎叶生长期、孕穗开花期、灌浆成熟期水分盈亏率每年分别以0.864、1.020、0.464、1.771的百分率增加,孕穗开花阶段增加不显著,全生育期水分盈亏率于2011年发生突变;从地区分布结果来看,水分盈亏率由东向西逐渐减小,河湟谷地水分亏缺较少,青海湖盆地次之,柴达木盆地水分亏缺严重;降水量对水分盈亏率产生显著的正效应,日照、风速、最低气温对水分盈亏率产生显著负效应。研究表明,青海省春小麦种植区气候呈现暖湿化趋势,并且春小麦水分亏缺问题严重,但亏缺程度有所减缓。该研究有助于掌握青海春小麦种植区的气候变化规律,并提高应对干旱灾害风险的能力。 展开更多
关键词 气候变化 春小麦 水分盈亏 青海省 暖湿化趋势
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C含量对基于马氏体温变形的高锰TRIP钢的影响 被引量:2
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作者 郭志凯 李龙飞 +1 位作者 杨王玥 孙祖庆 《材料热处理学报》 EI CAS CSCD 北大核心 2015年第7期144-149,共6页
利用Gleeble 1500热模拟试验机进行单轴压缩,通过基于马氏体温变形和两相区短时间退火的工艺制备了两种C含量的高锰TRIP钢,并结合扫描电镜、X射线和室温拉伸等实验研究了C含量对高锰TRIP钢制备过程的组织演变和室温力学性能的影响。结... 利用Gleeble 1500热模拟试验机进行单轴压缩,通过基于马氏体温变形和两相区短时间退火的工艺制备了两种C含量的高锰TRIP钢,并结合扫描电镜、X射线和室温拉伸等实验研究了C含量对高锰TRIP钢制备过程的组织演变和室温力学性能的影响。结果表明,C含量从0.08%提高到0.18%,降低了逆转变奥氏体的化学驱动力,不利于温变形过程中逆转变奥氏体的形成。但由于马氏体分解可得到较多的渗碳体粒子,提高C含量使得退火组织中马奥岛含量和残留奥氏体含量增多且残留奥氏体C含量增加,因此提高了高锰TRIP钢的强度和塑性。 展开更多
关键词 高锰trip 马氏体温变形 C含量 残留奥氏体 力学性能
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基于马氏体温变形的高锰TRIP钢组织演变 被引量:1
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作者 郭志凯 李龙飞 +1 位作者 杨王玥 孙祖庆 《材料热处理学报》 EI CAS CSCD 北大核心 2014年第10期130-137,共8页
通过热模拟压缩和两相区退火实验,结合SEM、XRD方法,研究基于马氏体温变形的高锰TRIP钢制备过程的组织演变,并分析了变形工艺和退火工艺对组织演变的影响。结果表明:高锰TRIP钢温变形促进马氏体分解及铁素体动态再结晶的发生,两相区变... 通过热模拟压缩和两相区退火实验,结合SEM、XRD方法,研究基于马氏体温变形的高锰TRIP钢制备过程的组织演变,并分析了变形工艺和退火工艺对组织演变的影响。结果表明:高锰TRIP钢温变形促进马氏体分解及铁素体动态再结晶的发生,两相区变形过程中可以形成奥氏体,同时渗碳体粒子溶解。随后两相区退火时,铁素体通过再结晶完成等轴化,奥氏体持续形成的同时渗碳体粒子逐渐溶解。通过高锰TRIP钢马氏体温变形加两相区退火工艺,可以在较小应变量和较短退火时间条件下获得由亚微米尺度的铁素体基体、马氏体和残留奥氏体组成的复相组织。 展开更多
关键词 高锰trip 马氏体 温变形 两相区退火 残留奥氏体
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The Role of Changes in the Annual Cycle in Earlier Onset of Climatic Spring in Northern China 被引量:13
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作者 钱诚 符淙斌 严中伟 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2011年第2期284-296,共13页
Climatic changes in the onset of spring in northern China associated with changes in the annual cycle and with a recent warming trend were quantified using a recently developed adaptive data analysis tool, the Ensembl... Climatic changes in the onset of spring in northern China associated with changes in the annual cycle and with a recent warming trend were quantified using a recently developed adaptive data analysis tool, the Ensemble Empirical Mode Decomposition. The study was based on a homogenized daily surface air temperature (SAT) dataset for the period 1955–2003. The annual cycle here is referred to as a refined modulated annual cycle (MAC). The results show that spring at Beijing has arrived significantly earlier by about 2.98 d (10 yr)-1, of which about 1.85 d (10 yr)-1 is due to changes in the annual cycle and 1.13 d (10 yr)-1 due to the long-term warming trend. Variations in the MAC component explain about 92.5% of the total variance in the Beijing daily SAT series and could cause as much as a 20-day shift in the onset of spring from one year to another. The onset of spring has been advancing all over northern China, but more significant in the east than in the west part of the region. These differences are somehow unexplainable by the zonal pattern of the warming trend over the whole region, but can be explained by opposite changes in the spring phase of the MAC, i.e. advancing in the east while delaying in the west. In the east of northern China, the change in the spring phase of MAC explains 40%–60% of the spring onset trend and is attributable to a weakening Asian winter monsoon. The average sea level pressure in Siberia (55°–80°N, 50°–110°E), an index of the strength of the winter monsoon, could serve as a potential short-term predictor for the onset of spring in the east of northern China. 展开更多
关键词 spring onset Ensemble Empirical Mode Decomposition modulated annual cycle Asian winter monsoon global warming
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Spring mesoscale high in the western South China Sea 被引量:3
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作者 HE Zhigang ZHANG Yan WANG Dongxiao 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2013年第6期1-5,共5页
A recurring spring mesoscale eddy in the western South China Sea (SCS) is studied using remote sensing data and historical in situ observations. The feature first appears east of the central Vietnam coast in Febru- ... A recurring spring mesoscale eddy in the western South China Sea (SCS) is studied using remote sensing data and historical in situ observations. The feature first appears east of the central Vietnam coast in Febru- ary as a high sea-level anomaly, grows rapidly to a well-developed anticyclonic eddy by March, matures in April, and decays in May. Besides the warm-core feature, it also has an inherent low-salinity property, so it is named "spring mesoscale high (SMH)". Though with clear interannual variation in terms of intensity and spatial coverage, the SMH always emerges in the region between ll0~E and l14~E and between 12~N and 16~N. The formation of SMH is ascribed to the combined effects of wind forcing and releasing of po- tential energy set up by winter monsoon. In particular, the wind-stress curl plays an important role in its development, maintenance, and dissipation. 展开更多
关键词 spring western South China Sea warm eddy
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Causes and Predictability of the 2021 Spring Southwestern China Severe Drought 被引量:5
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作者 Yunyun LIU Zeng-Zhen HU +1 位作者 Renguang WU Xing YUAN 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2022年第10期1766-1776,共11页
In the spring of 2021,southwestern China(SWC)experienced extreme drought,accompanied by the highest seasonal-mean temperature record since 1961.This drought event occurred in the decaying phase of a La Niña event... In the spring of 2021,southwestern China(SWC)experienced extreme drought,accompanied by the highest seasonal-mean temperature record since 1961.This drought event occurred in the decaying phase of a La Niña event with negative geopotential height anomalies over the Philippine Sea,which is distinct from the historical perspective.Historically,spring drought over SWC is often linked to El Niño and strong western North Pacific subtropical high.Here,we show that the extreme drought in the spring of 2021 may be mainly driven by the atmospheric internal variability and amplified by the warming trend.Specifically,the evaporation increase due to the high temperature accounts for about 30%of drought severity,with the contributions of its linear trend portion being nearly 20%and the interannual variability portion being about 10%.Since the sea surface temperature forcing from the tropical central and eastern Pacific played a minor role in the occurrence of drought,it is a challenge for a climate model to capture the 2021 SWC drought beyond one-month lead times. 展开更多
关键词 extreme spring drought Southwestern China precipitation EVAPORATION warming trend internal variability PREDICTABILITY
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INTERANNUAL VARIATION IN HEAT CONTENT OF THE WESTERN PACIFIC WARM POOL AND ITS EFFECT ON EASTERN ASIAN CLIMATE ANOMALIES 被引量:1
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作者 卢楚翰 黄露 +1 位作者 何金海 秦育婧 《Journal of Tropical Meteorology》 SCIE 2015年第3期246-254,共9页
Using the 1980-2010 winter GODAS oceanic assimilations, study is conducted of the winter heat content(HC) established in the subsurface layer(5 to 366 m in depth) over the western Pacific warm pool(WP), followed by in... Using the 1980-2010 winter GODAS oceanic assimilations, study is conducted of the winter heat content(HC) established in the subsurface layer(5 to 366 m in depth) over the western Pacific warm pool(WP), followed by investigating the HC spatiotemporal characteristics, persistence and the impacts on the climate anomalies of neighboring regions. Results are as follows: 1) the pattern of integral consistency is uncovered by the leading EOF1(PC1) mode of HC interannual variability, the year-to-year fluctuation of the time coefficients being well indicative of the interannual anomaly of the WP winter subsurface-layer thermal regime. The HC variation is bound up with El Ni觡o-Southern Oscillation, keeping pronounced autocorrelation during the following two seasons and more, with the persistence being more stable in comparison to sea surface temperature anomaly in the equatorial middle eastern Pacific; 2) the winter HC anomalies produce lasting effect on the WP thermal state in the following spring and summer and corresponding changes in the warm water volume lead to the meridional transport and vertical exchange of warm water, which exerts greater impacts upon the sea surface temperature/heat flux over the warm pool per se and neighboring regions, especially in the Philippine Sea during the posterior spring and summer; 3) the increase in the winter HC corresponds to the spring outgoing longwave radiation(OLR) decrease and richer precipitation over the waters east to the Philippine Sea and the resultant convective heating anomalies are responsible for the rise of geopotential isobaric surfaces over tropical and subtropical western North Pacific, thereby producing effect on the western Pacific subtropical high(anomaly). Subsequently, the sea-surface heat flux exchange is intensified in the warm pool, a robust anomalous cyclone shows up at lower levels, air-sea interactions are enhanced and abnormal convective heating occurs, together making the winter HC anomalies even more closely associated with the variation in the summer subtropical high. As a result, the WP winter HC can be used as an effective predictor of the variation in spring/summer western Pacific subtropical high and the strength of summer monsoon over the northwestern Pacific. 展开更多
关键词 heat content warm pool of the western Pacific SUBSURFACE spring barrier anomaly of eastern-Asian climate
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两相区退火中锰TRIP钢残余奥氏体含量与加工硬化行为 被引量:6
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作者 田亚强 黎旺 +4 位作者 郑小平 宋进英 魏英立 董福涛 陈连生 《塑性工程学报》 CAS CSCD 北大核心 2019年第2期199-205,共7页
采用ART (奥氏体逆相变)退火热处理工艺,研究了两相区温轧和退火过程中冷轧中锰TRIP钢中残余奥氏体体积分数变化与加工硬化行为。结果表明:冷轧实验钢经两相区温轧退火处理后,获得了临界铁素体与残余奥氏体或马氏体组成的超细晶复相组... 采用ART (奥氏体逆相变)退火热处理工艺,研究了两相区温轧和退火过程中冷轧中锰TRIP钢中残余奥氏体体积分数变化与加工硬化行为。结果表明:冷轧实验钢经两相区温轧退火处理后,获得了临界铁素体与残余奥氏体或马氏体组成的超细晶复相组织。在645℃,随退火时间的延长,受少量碳化物析出及溶解与C、Mn元素富集程度的影响,残余奥氏体含量由20. 8%先下降至18. 7%后回升至22. 8%最后又骤降至4. 5%。退火时间小于5 h时,实验钢持续加工硬化水平较高,其中均匀塑性形变阶段中,加工硬化指数随退火时间增加,表现出先升高后降低的变化趋势,在退火1 h时加工硬化能力达到最高。 展开更多
关键词 两相区温轧退火 中锰trip 碳化物析出 残余奥氏体 加工硬化速率
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Warm compaction behaviors of iron-based powder lubricated by different kinds of graphite
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作者 肖志瑜 李元元 +2 位作者 倪东惠 郭国文 陈维平 《中国有色金属学会会刊:英文版》 CSCD 2003年第5期1181-1184,共4页
Warm compaction behaviors and their affecting factors such as compaction temperature, compaction pressure and lubricant concentration were studied. Effect of die wall lubrication on the powder’s warm compaction behav... Warm compaction behaviors and their affecting factors such as compaction temperature, compaction pressure and lubricant concentration were studied. Effect of die wall lubrication on the powder’s warm compaction behavior was also studied. The use of smaller size colloidal graphite investigated can give a higher compact density and lesser spring back effect than the use of flake graphite. 展开更多
关键词 预热压缩 离子基粉末冶金 反冲影响 石墨
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创作与表演双重视角下的当代筝乐演绎——以《暖春》的演奏实践为例 被引量:1
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作者 刘文佳 《黄钟(武汉音乐学院学报)》 北大核心 2023年第2期135-142,168,共9页
《暖春》是作曲家赵曦应湖北省音乐家协会古筝专业委员会委约,从2020年2月至2021年2月,历时一年创作的古筝与管弦乐队作品,作曲家以此讴歌为武汉送来“暖春”的人们。文章以作品创作构思、乐谱完善、演绎过程为依据,着重探讨了创作与表... 《暖春》是作曲家赵曦应湖北省音乐家协会古筝专业委员会委约,从2020年2月至2021年2月,历时一年创作的古筝与管弦乐队作品,作曲家以此讴歌为武汉送来“暖春”的人们。文章以作品创作构思、乐谱完善、演绎过程为依据,着重探讨了创作与表演双重视角下的交互融合对作品演绎所产生的积极意义。 展开更多
关键词 赵曦 暖春 创作 表演 当代筝乐
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近50年广东春运期间气温和降水协同变化的气候特征
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作者 汪明圣 胡娅敏 +2 位作者 胡婷 董少柔 赵亮 《热带气象学报》 CSCD 北大核心 2023年第2期230-241,共12页
根据近50年(1971—2020年)广东省86个气象站的观测数据、NCEP/NCAR再分析数据和NOAA海温数据,采用线性趋势分析、合成分析等统计方法,研究了广东春运期间气温和降水的时空分布特征,从气温降水协同变化的角度切入划分了气候异常类型,并... 根据近50年(1971—2020年)广东省86个气象站的观测数据、NCEP/NCAR再分析数据和NOAA海温数据,采用线性趋势分析、合成分析等统计方法,研究了广东春运期间气温和降水的时空分布特征,从气温降水协同变化的角度切入划分了气候异常类型,并对比分析了其异常成因。结果表明:近50年来,广东省春运期间平均气温呈现显著上升趋势,珠江三角洲和粤东地区最明显。而降水日数则表现出显著减少趋势,粤西北、粤东和粤西沿海最明显。气温和降水协同变化的异常年(冷湿(4年)、冷干(6年)和暖干(11年))共有21年,占全部年份的42%。冷湿年和冷干年,欧亚大陆中高纬度都表现出经向环流特征,西伯利亚高压偏强,有利于冷空气活跃南下。不同的是冷湿年东亚西部地区“北高南低”,低纬度地区“东高西低”,对应的冷空气路径为中、西路,有利于水汽输送;而冷干年东亚东部地区“北高南低”,低纬度地区一致偏低,对应的冷空气路径偏东,不利于水汽输送。另外,冷湿年前期赤道中东太平洋偏暖,呈现ElNiño状态,受其影响西太平洋副热带高压偏大偏强,西太暖池偏冷,在菲律宾海区域激发出一个反气旋性环流,有利于西南水汽输送到广东地区,降水偏多;而冷干年则相反。暖干年,东亚中高纬表现出“北低南高”的纬向环流分布,东亚大槽和西伯利亚高压偏弱,不利于冷空气的生成和南下,广东上空受反气旋式环流控制,辐散下沉,温高雨少。 展开更多
关键词 广东 春运 协同变化 气候特征 冷湿 冷干 暖干
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热解温度和氮肥用量影响生物炭的减排和增产效应 被引量:1
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作者 钟佳旺 张丽 +4 位作者 詹祥生 刘榕 董勤各 张曼 冯浩 《植物营养与肥料学报》 CAS CSCD 北大核心 2023年第4期664-676,共13页
【目的】研究生物炭性质与氮肥用量对河套灌区春玉米田温室气体排放和产量的影响,为河套灌区高效利用生物炭固碳减排提供理论支撑。【方法】试验采用室内培养与田间试验相结合的方法,供试材料为秸秆生物炭和竹炭。田间试验设常规施氮300... 【目的】研究生物炭性质与氮肥用量对河套灌区春玉米田温室气体排放和产量的影响,为河套灌区高效利用生物炭固碳减排提供理论支撑。【方法】试验采用室内培养与田间试验相结合的方法,供试材料为秸秆生物炭和竹炭。田间试验设常规施氮300 kg/hm^(2)对照(N)、常规氮量配施秸秆炭(SB+N)、常规氮量配施竹炭(BB+N)、减氮50%配施秸秆炭(SB+50%N)、减氮50%配施竹炭(BB+50%N)。采用静态暗箱–气象色谱法测定春玉米田温室气体排放量,并测定玉米产量。室内培养试验中分别制备热解温度为200℃、400℃和600℃的秸秆炭(S)和竹炭(B)加入土壤中,平衡3天后施入N 300 kg/hm^(2)开始恒温恒湿培养,共培养14天。监测了不同培养时间土壤中N_(2)O、CO_(2)及CH_(4)气体的排放通量。【结果】与N处理相比,SB+N、BB+N、SB+50%N和BB+50%N处理0—5 cm深土壤温度分别提高了0.50℃、1.84℃、0.35℃和1.37℃,0—10 cm深土壤温度分别提高了0.43℃、1.83℃、0.39℃和1.11℃;0—10 cm土壤含水率分别提高13.70%、8.90%、12.33%和8.90%。与N处理相比,在春玉米整个生育期内SB+N、BB+N、SB+50%N和BB+50%N处理的土壤N_(2)O累积排放量分别减少了21.91%、23.16%、25.98%和28.17%(P<0.05);SB+N和BB+N处理的CO_(2)累积排放量分别提高了7.96%和9.94%(P<0.05),而SB+50%N和BB+50%N处理的分别降低了11.54%和10.74%(P<0.05);整个春玉米生育期各生物炭处理的CH_(4)累积排放量为负值,显著低于N处理(P<0.05);SB+N、BB+N、SB+50%N和BB+50%N处理土壤的全球增温潜势(GWP)分别降低了23.26%、23.98%、27.00%和29.14%,温室气体排放强度(GHGI)分别降低了27.24%、28.97%、32.57%和34.68%(P<0.05)。生物炭添加能够提高玉米产量,SB+N、BB+N、SB+50%N和BB+50%处理较N处理分别增加5.47%、7.01%、8.26%和8.47%(P<0.05)。培养试验发现生物炭能够减少土壤N_(2)O和CO_(2)的排放。N_(2)O和CO_(2)的排放通量随生物炭热解温度升高而减少,在相同热解温度下,竹炭的减排效果优于秸秆炭。各处理下土壤CH_(4)的排放均表现为碳汇,其中600℃制备的竹炭对CH_(4)的吸收量最高。【结论】施用生物炭能够改善土壤温度和土壤含水率,并显著降低N_(2)O和CH_(4)累积排放量,但常规施氮量下施用生物炭会提高CO_(2)累积排放量。施用生物炭能够显著提高春玉米的产量并降低春玉米田GWP和GHGI。培养试验进一步说明了竹炭的减排效果优于秸秆炭,高热解温度的生物炭减排效果优于低热解温度生物炭,综合考虑田间与室内培养试验的结果、环境效益和经济效益,减氮50%配施竹炭的处理是河套灌区春玉米田提高产量并减少温室气体排放较为合适的措施。 展开更多
关键词 生物炭 裂解温度 氮肥用量 增温潜势 春玉米产量
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河套灌区垄膜沟灌模式对春玉米田水热运移及籽粒产量的影响 被引量:2
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作者 吴旭斌 冯浩 +2 位作者 董勤各 钟佳旺 赵鹏 《节水灌溉》 北大核心 2023年第6期100-109,116,共11页
河套灌区降水稀少、昼夜温差大,早春温度偏低影响春玉米生长,为改善灌区春玉米水热环境,以不同覆膜与灌溉组合为研究对象,探究适宜的保墒增温和提质增效的覆膜灌溉耕作模式,为河套灌区水热资源的高效利用提供理论指导与技术支撑。试验布... 河套灌区降水稀少、昼夜温差大,早春温度偏低影响春玉米生长,为改善灌区春玉米水热环境,以不同覆膜与灌溉组合为研究对象,探究适宜的保墒增温和提质增效的覆膜灌溉耕作模式,为河套灌区水热资源的高效利用提供理论指导与技术支撑。试验布设4个处理:畦灌+不覆膜(CK)、畦灌+透明地膜覆盖(QB)、沟灌+透明地膜垄体覆盖(GB)、沟灌+黑色地膜垄体覆盖(GH),以探究不同覆膜灌溉方式下春玉米田土壤含水率和土壤温度变化规律、春玉米产量及水热资源利用效率。结果表明:垄膜沟灌可提高表层土壤含水率和根区储水量。播后61d,GH、GB和QB处理根区土壤储水量分别较CK增加36.01%、36.61%和21.37%,且垄膜沟灌显著高于覆膜畦灌。播后133 d,GH根区土壤储水量较CK和QB增加19.02%和17.40%。垄膜沟灌有效提高日均土壤温度,GB生育期日均土壤温度较QB和CK平均增加1.01℃和1.59℃,GH较QB和CK平均增加0.86℃和1.44℃。垄膜沟灌土壤有效积温显著高于畦灌处理,其中GB较QB和CK提高7.78%和16.70%;GH较QB提高6.26%,较CK提升14.46%。春玉米产量呈现出与百粒重结果相同的显著性差异,其中QB较CK提升16.19%,GB较QB提升13.64%,较CK提升32.04%。GB处理下水分利用效率(WUE)和土壤有效积温生产效率(TUE)较QB提升25.79%和5.41%,较CK提升45.69%和13.66%。GB可有效提升根区土壤储水量及温度,改善春玉米水热资源利用效率,提高籽粒产量。综上,建议在内蒙古河套灌区推行沟灌+透明地膜垄体覆盖技术,以提高春玉米产量及水热资源利用效率。 展开更多
关键词 耕作模式 灌溉方式 垄膜沟灌 水热特性 保墒增温 根区土壤储水量 土壤有效积温 春玉米产量 水热利用效率
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