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1.
【目的】制作柳州市甘蔗干旱风险区划图,为甘蔗的防旱避灾和种植布局的优化提供科学参考。【方法】利用柳州市8个气象观测站1961-2014年的气象资料,结合甘蔗的发育期,同时,在水分亏缺指数理论基础上,以水分亏缺指数及其发生的概率和各生育阶段的权重系数为评价指标,构建柳州市甘蔗干旱风险指数,最后制作风险区划图。【结果】伸长期和成熟期水分亏缺指数较大,干旱频率较高;柳州市区以东和鹿寨县以南的地区、柳城县中部处于高风险区,三江县西南部、融安县大部分处于中风险区,融水县大部分地区和融安县以西的小部分地区处于低风险区。【结论】柳州市干旱风险空间差异较大,区划结果可为合理安排种植布局、制定科学灌溉用水调配计划提供科学参考。  相似文献   

2.
以活力抗旱指数作为玉米萌芽期抗旱性评价指标的初探   总被引:8,自引:0,他引:8  
首次提出了活力抗旱指数,并以此为指标,在PEG人工模拟水分胁迫的条件下,对18个不同的玉米品种进行抗旱性研究。结果表明:活力抗旱指数和常用的萌发抗旱指数有很高的相关性,且能更好的反映不同品种幼苗水分胁迫下的差别,可以作为玉米萌发阶段抗旱性鉴定的筛选方法。  相似文献   

3.
准确及时地监测作物干旱情况可为应对作物受灾减产提供策略,进而降低经济损失。研究基于重建的归一化植被指数(NDVI)和地表温度(LST)数据构建旱地作物生育期内LST-NDVI特征空间,计算温度植被干旱指数(TVDI),结合研究区实地观测数据对TVDI指数进行定量验证。结果表明,构建的NDVI-Ts特征空间散点图符合三角形关系,与前人研究结果相符;旱地作物不同生育阶段TVDI与土壤湿度均呈负相关性,表明TVDI具备反映研究区土壤湿润条件的能力;2017年黑龙江旱地作物生育期内各时段均有干旱状况发生,其中西部地区干旱发生频率和范围整体大于东部地区;TVDI与土壤相对湿度干旱等级判对率一致性达到90%以上。综上所述,基于MODIS数据构建的TVDI指数可以反映黑龙江省旱地作物干旱情况,研究可为作物生育期多时段干旱监测的业务化运行及为黑龙江省制定抗旱减灾策略提供科学参考依据。  相似文献   

4.
山西北部农业干旱的原因及防御对策   总被引:2,自引:1,他引:1  
为了探究造成山西北部地区农业干旱的气象因子,以便有针对性地提出应对干旱措施,通过彭曼公式和玛格努斯经验公式确定影响蒸发量的主要气候因子,利用近50年的气象资料,采用线性趋势分析和多项式拟合对山西省北部地区春季及初夏阶段干旱的成因进行分析。结果表明:造成山西省北部地区干旱的根本原因是降水量与蒸发量之间的不平衡,降水的主要时段是发生在6-9月,而蒸发量的峰值却出现在4-7月,这种情况造成春季到初夏时段降水量与蒸发量失去平衡。另外,由于气温以0.33℃/10 a的速率升高,饱和差以0.17 hpa/10 a的频率递增,从而造成蒸发量的加大。日照时数对蒸发量的贡献一般,50年来蒸发量的上升率为5.06 mm/10 a,相同时段内的日照时数却呈现下降之势,速率-2.84 h/10 a。说明日照时数不是干旱出现的主要因子。山西北部地区干旱的影响因子与全国大部地区基本相同,但更接近北方地区。  相似文献   

5.
【目的】旨在探讨山东省各市农业抗旱能力的强弱、空间分布特征以及主要影响因素。【方法】在分析农业抗旱能力影响因素的基础上,构建农业抗旱能力综合评价指标体系,分别用层次分析法(AHP)、熵值法(EM)和主成分分析法(PCA)对山东省农业抗旱能力进行综合评价,为了避免评价结果的非一致性,建立循环组合优化模型对三种单一评价方法进行组合评价。【结果】将山东省17个市的农业抗旱能力进行了强弱排序,并根据聚类分析结果把17个市分为四类,得出了各类地区农业抗旱能力的主要影响因素。【结论】循环组合优化评价方法提高了评价结果的准确性和一致性,针对不同类型的区域提出了相应措施以增强农业抗旱能力,进而为山东抗旱规划和旱灾风险管理提供科学参考。  相似文献   

6.
近60年农业生产期干旱发生风险分析   总被引:4,自引:1,他引:3  
采用叶柏寿、朝阳气象站1953—2012 年气象资料,运用积分湿度指数、水平衡和干湿指数,评价辽西地区农业生产期大气降水及农业耗水、农业需水的满足度及不同时期旱涝频率。结果表明:1953—2012 年农业生产期大气降水减少,气候变化率为-9.343 mm/10 a;农业耗水量在增加,气候变化率为6.966 mm/10 a;农业生产期水分平均亏缺-136 mm。降水资源农业满足度为76.3%,缺水概率为90.0%。辽西地区农业生产期属于半湿润半干旱气候类型,重旱及以上年景占5.0%;干旱发生风险近10年增加约10%。总之,辽西地区降水在减少、耗水在增加、农业需水满足度在下降、干旱发生风险在增强。近10年随着气候变暖辽西地区农业生长期从半干旱半湿润气候类型升级为半干旱气候类型。  相似文献   

7.
Eighteen cultivars of legume species (field bean, soybean, field pea, lupine) were screened for drought tolerance in 3 year-long field experiments. The aim of the investigations was to evaluate the generic variation of drought susceptibility of the tested varieties. The experimental plots were equipped with an installation which enabled the limitation of the water content in soil and soil irrigation. The applied drought susceptibility index (DSI) considered the relations between seed yield of plants under drought conditions (YD) and that under conditions of good soil watering (YIR) as well as their dependence on the drought severity index (DS). The use of the index divided the cultivars into two groups of different drought tolerances. The group of drought resistant cultivars characterized by mean values of the DSI index < 0.31 comprised field bean cultivars Bourdon, Gobo and Nadwislanski, soybean cultivars Aldana, Polan and Progres, field pea cultivars Miko and Solara and lupine cultivars Popiel and Bac. To the drought sensitive cultivars with DSI > 0.44 belonged Victor and Bronto of field bean species, Bareness and Mige of field pea species and Emir of lupine species. In general, the resistant cultivars when compared with the susceptible ones were characterized by lesser yield of seeds, which, however, was more stable both under conditions of drought and moistured plots. Any dependence of the degree of drought tolerance on the duration of the particular periods of plant growth was not observed in the experiments, however, both in’ drought susceptible and drought resistant cultivars there appeared the tendency to shorten the development phases under drought and to prolong them under artificial irrigation. In general, based on the results obtained, it can be concluded that legume plants belong to the species sensitive to water supply. The observed decrease of plant seed yield under moderate natural soil dryness in the year 1993 differed only a little from that found in experiments in the years 1994 and 1995, when soil dryness was much more severe.  相似文献   

8.
为减轻旱灾损失,根据2005、2015年河南省统计与气象数据,采用10项指标和灰色关联分析法,以最劣值为参照系列分析了该省农业旱灾脆弱性.结果 表明,豫西的济源、三门峡、洛阳,豫东的开封、漯河与豫北的鹤壁是河南省干旱脆弱性较强的区域,而豫东南的商丘、驻马店、信阳,豫北的新乡、豫西南的南阳则脆弱性较弱,其他地区居于两者之...  相似文献   

9.
不同高产玉米品种抗旱性的比较研究   总被引:4,自引:1,他引:3  
为了有效筛选出适合鲁东半干旱区应用的夏玉米品种,以山东省目前主推的9个玉米品种为试材,通过2010-2011年连续2年防雨棚控水干旱试验,以抗旱隶属度、抗旱指数为评价参数,对各品种进行抗旱性综合评价。结果表明,干旱胁迫导致各品种玉米株高、穗位高、穗长、穗粒重均不同程度地降低,茎秆变细,秃尖变长,产量降低。年份间比较,2011年夏玉米植株性状、穗部性状、地上部干物重、产量均显著高于2010年。以茎秆性状、穗部性状、地上部干物重及产量指标隶属度的平均值为综合评价标准,‘登海701’为典型抗旱性品种;‘莱农14’、‘农大108’、‘金海5号’为抗旱性较强的品种;‘登海662’、‘郑单958’、‘中科11’、‘浚单20’为抗旱性弱的品种;‘青农105’在2年内的隶属度值差异较大,其抗旱性有待进一步研究。  相似文献   

10.
玉米抗旱机理及抗旱性鉴定指标研究进展   总被引:13,自引:3,他引:10  
玉米抗旱性是一个复杂的综合特性,研究内容主要是抗旱机理研究和抗旱性鉴定与评价,其中适应干旱的形态结构特征是玉米长期进化的结果,生理代谢调节也是玉米适应抗旱的有效手段之一。通过总结前人有关对玉米抗旱性的大量研究,从形态结构、生理生化及遗传等角度阐述了玉米抗旱机理与抗旱性鉴定的各项指标。指出玉米抗旱性由多基因控制,呈现典型的数量遗传。抗旱性鉴定需要在特定环境和试验条件下运用生理生化指标变化结合遗传分析进行综合评价。同时发现玉米抗旱性研究的方向从一般的生理生化分析转移到分子遗传学的QTLs定位与分析。总结分析玉米抗旱性研究现状与方向,为玉米抗旱性鉴定、玉米抗旱育种和农业生产提供可靠的理论依据。  相似文献   

11.
Drought tolerance is an increasingly important trait in common bean ( Phaseolus vulgaris L.) due to the reduction in water resources, a shift in production areas and increasing input costs. The objective of this study was to evaluate 29 genotypes for drought tolerance under drought stress (DS) and reduced stress treatments in Juana Diaz, Puerto Rico. The use of DS and reduced stress treatments facilitated the identification of drought tolerant germplasm that also had good yield potential under more optimal conditions. Based on the results of seed yield under DS and reduced stress conditions, and DS indices, including the geometric mean (GM), stress tolerance index (STI) and percent yield reduction (YR), genotypes were identified with greater yield potential under the tested environment. Based on average GM over the 2 years, the superior common bean genotypes identified were SEA 5, G 21212, A 686, SEN 21 and SER 21. These genotypes performed well in both years and under both treatment conditions and thus may serve as parents for DS improvement and genetic analysis.  相似文献   

12.
基于作物水分生产函数的冬小麦干旱评估模型   总被引:1,自引:1,他引:0  
干旱是影响华北冬小麦生产的主要灾害之一。为定量评估干旱对冬小麦产量的影响,利用作物水分生产函数,建立了河北省冬小麦干旱评估模型。本研究选择河北省冬麦区南宫、河间、霸州等农业气象观测站,基于3站1991-2007年冬小麦观测数据及气象资料,采用Penman-Monteith公式计算冬小麦各生育阶段的相对蒸散量,以联合国粮农组织(FAO)“农作物生产潜势”方法估算的光温生产潜力作为最大产量,应用统计方法求解Jensen模型参数,并以该模型为基础建立干旱评估模型。结果表明,各站冬小麦水分敏感系数与冬小麦全生育期灌溉次数关系密切。对于灌溉3次的南宫、河间二站,利用大田种植条件下的数据,得到的冬小麦水分敏感阶段与试验的结论相似,呈前期小、中期大、后期又变小的变化趋势;全生育期干旱评估模型的模拟和预测结果与实际产量相关较好,相关系数通过了0.01的显著性统计检验。应用干旱评估模型对冬小麦播种-拔节、播种-抽穗、播种-灌浆、播种-成熟各阶段的干旱评估结果与实际相符。霸州一般灌溉5次,干旱胁迫不明显,仅抽穗-灌浆期水分敏感系数为正值,其他生育阶段均为负值,对水分亏缺表现不敏感。  相似文献   

13.
Remotely sensed infrared canopy temperatures provide an efficient method for rapid, non-destructive monitoring of whole-plant response to water stress. Field studies were conducted in 1992 and 1993 to evaluate the potential for using canopy temperatures to screen for drought tolerance in wheat. In both years, 12 spring wheat (Triticum aestivum L.) genotypes were grown under two irrigation levels (well-watered and moisture-stressed) imposed between tillering and anthesis with a line-source sprinkler irrigation system. Canopy temperature measurements were taken in well-watered and moisture-stressed plots between 1330 and 1430 h (MDT) on five clear days in 1992 and seven clear days in 1993 during the late vegetative and early reproductive growth periods following closure of the plant canopy. Genotypes exhibited differences in mean canopy temperatures across the two irrigation levels and two years. Klasic consistently had the highest canopy temperature under moisture-stressed conditions, while Bannock and Pondera had the lowest. Bannock, Yecora Rojo and Klasic had the warmest canopies under well-watered conditions, while Vandal, Amidon and Rick had the coolest. Plot-to-plot variation in canopy temperature under water stress conditions was evident for differences in grain yield. Significant correlations between canopy temperature and yield under moisture-stress conditions and drought susceptibility index values indicated the potential for screening wheat genotypes for drought response.  相似文献   

14.
Barley (Hordeum vulgare L.) is an important winter cereal crop grown in the semiarid Mediterranean, where late‐terminal drought stress during grain filling has recently become more common. The objectives of this study were to investigate the growth performance and grain yield of four barley cultivars under late‐terminal drought stress under both glasshouse and field conditions. At grain filling, four barley cultivars (Rum, ACSAD176, Athroh and Yarmouk) were exposed to three watering treatments: (1) well‐watered [soil maintained at 75 % field capacity (FC)], (2) mild drought stress at 50 % FC, (3) severe drought stress at 25 % FC in the glasshouse experiment and (1) well‐watered (irrigated once a week), (2) mild drought (irrigated once every 2 weeks), (3) severe drought (non‐irrigated; rainfed) in the field. As drought stress severity increased, gross photosynthetic rate, water potential, plant height, grain filling duration, spike number per plant, grain number per spike, 1000‐grain weight, straw yield, grain yield and harvest index decreased. In the glasshouse experiment, the six‐row barley cultivars (Rum, ACSAD176, and Athroh) had higher grain yield than the two‐row barley cultivar (Yarmouk), but the difference was not significant among the six‐row cultivars under all treatments. In the field experiment, Rum had the highest grain yield among all cultivars under the mild drought stress treatment. The two‐row cultivar (Yarmouk) had the lowest grain yield. In general, the traditional cultivar Rum had either similar or higher grain yield than the other three cultivars under all treatments. However, the yield response to drought differed between the cultivars. Those, Rum and ACSAD176, that were capable of maintaining a higher proportion of their spikes and grains per spike during drought also maintained a higher proportion of their yield compared with those in well‐watered treatment. In conclusion, cultivar differences in grain yield were related to spike number per plant and grain number per spike, but not days to heading or grain filling duration.  相似文献   

15.
在人工控水条件下, 以抗旱品种济薯21和不抗旱品种济紫薯1号为试验材料, 设置全生育期干旱胁迫(DS)、发根分枝期干旱胁迫(DS1)、蔓薯并长期干旱胁迫(DS2)、快速膨大期干旱胁迫(DS3) 4个处理, 全生育期正常灌水(WW)为对照, 研究其对甘薯内源激素及块根产量的影响。结果表明, 与对照相比, 2个品种不同年份的所有干旱胁迫处理的鲜薯和薯干产量均显著下降。其中, DS薯干产量减产幅度最大, 济薯21和济紫薯1号3年平均分别减产44.62%和56.21%; 其次是DS1, 减产32.03%和44.03%; 再次是DS2, 减产30.41%和39.39%; DS3的减产幅度最小, 为13.66%和17.88%。抗旱品种济薯21的减产幅度小于不抗旱品种济紫薯1号。干旱胁迫抑制了甘薯地上部生长及块根的形成和膨大, 两个品种的单株叶片数、蔓长、地上部干重、地下部干重和块根淀粉率, 与对照相比, 各时期均表现为, DS的减少幅度最大, 其次是DS1和DS2, DS3的减少幅度最小。不同时期干旱胁迫均引起叶片和块根中GA、IAA和ZR含量下降, ABA含量上升。地上部干重与叶片GA、IAA和ZR含量呈显著正相关, 与ABA含量呈显著负相关; 地下部干重与块根GA、IAA和ZR含量呈显著正相关, 与ABA含量呈显著负相关。总之, 不同时期干旱胁迫均导致甘薯产量下降, 且胁迫时间越早, 对甘薯内源激素和块根产量的影响越大, 发根分枝期是甘薯对水分最敏感的时期。  相似文献   

16.
为研究西藏主要农区青稞的干旱时空变化特征,笔者从干旱灾害的致灾因子危险性、承灾体易损性、灾损脆弱性、防灾减灾能力等4个风险因子考虑,采用专家打分法和熵权法确定各因素权重,构建干旱灾害风险综合评估模型,并进行干旱灾害时空格局分析.结果表明:干旱灾害综合风险整体呈现中间低、两边高的态势,高风险区分布比较分散,次高风险区多集...  相似文献   

17.
The ability of a plant to modify its root distribution to exploit deeper stored soil water may be an important mechanism to avoid drought. This study aimed at assessing root distributions, variations in root length density (RLD) and percentage of root distribution, and the relevance of root traits for yield of drought‐resistant peanut genotypes under different available soil water levels. The experiment was conducted in the dry season during the years 2003/04 and 2004/05. Eleven peanut genotypes (ICGV 98300, ICGV 98303, ICGV 98305, ICGV 98308, ICGV 98324, ICGV 98330, ICGV 98348, ICGV 98353, Tainan 9, KK 60‐3 and Tifton‐8) and three soil moisture levels [field capacity (FC), 2/3 available soil water (AW) and 1/3 AW] were laid out in a split‐plot design with four replications. Roots were sampled by a core sampler at 37, 67 and 97 days after sowing (DAS). Root length was determined by a scanner and the WINRHIZO Pro 2004a software. RLD was calculated as the ratio of root length (cm) and soil volume (cm3). Graphical illustration of root distribution was constructed by merging RLD in the first and second soil layers (0–40 cm) as upper roots and pooling RLD at the third, fourth and fifth layers (40–100 cm) as lower roots. Pod yield, biomass and harvest index (HI) were recorded at harvest. A drought tolerance index (DTI) was calculated for each parameter as the ratio of the parameter under stress treatment to that under well‐watered conditions. Variations in RLD in 40 to 100 cm layer (RLD40 to 100 cm) were found under well‐watered conditions, and the peanut genotypes could be readily identified as high, intermediate and low for this trait. Changes in RLD in the 40 to 100 cm soil layer were found at 2/3 AW and were more evident at 1/3 AW. ICGV 98300, ICGV 98303, ICGV 98305, ICGV 98308 and KK 60‐3 were classified as drought responsive as they increased RLD in the deeper subsoil level in response to drought. In general, RLD under drought conditions was not related to biomass production. The ability to maintain the percentage of RLD (DTI for %RLD) was related to pod yield, DTI for pod yield and DTI for HI. ICGV 98300, ICGV 98303, ICGV 98305 exhibited high DTI (RLD40 to 100 cm) which may explain their high pod yield, DTI (PY) and DTI (HI). Based on these observations we classified them as drought‐avoiding genotypes.  相似文献   

18.
Sub‐Saharan Africa (SSA) faces twin challenges of water stress and food insecurity – challenges that are already pressing and are projected to grow. Sub‐Saharan Africa comprises 43 % arid and semi‐arid area, which is projected to increase due to climate change. Small‐scale, rainfed agriculture is the main livelihood source in arid and semi‐arid areas of SSA. Because rainfed agriculture constitutes more than 95 % of agricultural land use, water scarcity is a major limitation to production. Crop production, specifically staple cereal crop production, will have to adapt to water scarcity and improved water productivity (output per water input) to meet food requirements. We propose inclusion and promotion of drought‐tolerant cereal crops in arid and semi‐arid agro‐ecological zones of SSA where water scarcity is a major limitation to cereal production. Sorghum uniquely fits production in such regions, due to high and stable water‐use efficiency, drought and heat tolerance, high germplasm variability, comparative nutritional value and existing food value chain in SSA. However, sorghum is socio‐economically and geographically underutilized in parts of SSA. Sorghum inclusion and/or promotion in arid and semi‐arid areas of SSA, especially among subsistence farmers, will improve water productivity and food security.  相似文献   

19.
Drought stress is the most pervasive threat to sustainable rice production and mainly disrupts membrane structure and cell-water relations. Exogenously applied brassinosteroids (BRs) may produce profound changes that may improve drought tolerance in rice. In this study, we monitored some physiological basis of the exogenously applied BRs in improving drought tolerance in fine grain aromatic rice ( Oryza sativa L.). Two BRs i.e. 28-homobrassinolide (HBL) and 24-epibrassinolide (EBL) were used both as seed priming and foliar spray. To prime, the seeds were soaked in 0.01 μ m aerated solution each of HBL and EBL for 48 h and dried back to original weight. Treated and untreated seeds were sown in plastic pots with normal irrigation in a phytotron. At four-leaf stage (3 weeks after sowing), plants were subjected to drought stress at 50 % field capacity by cutting down the water supply. For foliar spray, 0.01 μ m of HBL and EBL solutions were sprayed at five-leaf stage. Drought stress severely reduced fresh and dry weights, whilst exogenously applied BRs improved net CO2 assimilation, water use efficiency, leaf water status, membrane properties, production of free proline, anthocyanins, soluble phenolics, but declined the malondialdehyde and H2O2 production. In conclusion, BRs application improved the leaf water economy and CO2 assimilation, and enabled rice to withstand drought. Moreover, foliar spray had better effect under drought than seed treatments and of the two BRs, EBL proved more effective.  相似文献   

20.
不同品种小黑麦萌发期耐旱性比较   总被引:2,自引:0,他引:2  
用不同浓度的聚乙二醇-6000(PEG-6000)溶液处理7个品种的小黑麦种子,测定其发芽率,发芽指数,活力指数、胚根、胚鞘、胚芽长度.结果表明,低浓度PEG-6000对小黑麦种子萌发有促进作用,随着胁迫浓度的增加,对种子萌发的抑制作用明显增强.不同品种表现不同,其中中新830最耐旱,中饲828、中饲237抗旱能力较强,冀饲1号、冀饲2号、NTH 1048、NTH1888耐旱程度中等,劲松49为干旱敏感品种.  相似文献   

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