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Estimating the Drought-Induced Yield Loss for Winter Wheat in a Semi-Arid Region of the Southern United States Using a Drought Index
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作者 Prem Woli Qingwu Xue +2 位作者 Gerald R. Smith Charles R. Long Francis M. Rouquette Jr. 《Agricultural Sciences》 2024年第8期812-829,共18页
The economy of most rural locations in the semi-arid region of Llano Estacado in the southern United States is predominantly based on agriculture, primarily beef and wheat (Triticum aestivum L.) production. This regio... The economy of most rural locations in the semi-arid region of Llano Estacado in the southern United States is predominantly based on agriculture, primarily beef and wheat (Triticum aestivum L.) production. This region is prone to drought and is projected to experience a drier climate. Droughts that coincide with the critical phenological phases of a crop can be remarkably costly. Although drought cannot be prevented, its losses can be minimized through mitigation measures if it is predicted in advance. Predicting yield loss from an imminent drought is an important need of stakeholders. One way to fulfill this need is using an agricultural drought index, such as the Agricultural Reference Index for Drought (ARID). Being plant physiology-based, ARID can represent drought-yield relationships accurately. This study developed an ARID-based yield model for predicting the drought-induced yield loss for winter wheat in this region by accounting for its phenological phase-specific sensitivity to water stress. The reasonable values of the drought sensitivity coefficients of the yield model indicated that it could reflect the phenomenon of water stress decreasing the winter wheat yields in this region reasonably. The values of the various metrics used to evaluate the model, including Willmott Index (0.86), Nash-Sutcliffe Index (0.61), and percentage error (26), indicated that the yield model performed fairly well at predicting the drought-induced yield loss for winter wheat. The yield model may be useful for predicting the drought-induced yield loss for winter wheat in the study region and scheduling irrigation allocation based on phenological phase-specific drought sensitivity. 展开更多
关键词 ARID drought drought index Growth-stage model Phenological-Phase Prediction SEMI-ARID Wheat Yield
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Introducing a drought index to a crop model can help to reduce the gap between the simulated and statistical yield
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作者 WANG Guo-Cheng ZHANG Qing XU Jing-Jing 《Atmospheric and Oceanic Science Letters》 CSCD 2018年第4期307-313,共7页
A well-established and pre-calibrated crop model can normally represent the overall characteristics of crop growth and yield.However,it can hardly include all relevant factors that affect the yield,and usually overest... A well-established and pre-calibrated crop model can normally represent the overall characteristics of crop growth and yield.However,it can hardly include all relevant factors that affect the yield,and usually overestimates the crop yield when extreme weather conditions occur.In this study,the authors first introduced a drought index(the Standardized Precipitation Evapotranspiration Index)into a process-based crop model(the Agro-C model).Then,the authors evaluated the model’s performance in simulating the historical crop yields in a double cropping system in the Huang-Huai-Hai Plain of China,by comparing the model simulations to the statistical records.The results showed that the adjusted Agro-C model significantly improved its performance in simulating the yields of both maize and wheat as affected by drought events,compared with its original version.It can be concluded that incorporating a drought index into a crop model is feasible and can facilitate closing the gap between simulated and statistical yields. 展开更多
关键词 Agro-C model CROP YIELD drought index
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Regional Climate Index for Floods and Droughts Using Canadian Climate Model (CGCM3.1)
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作者 Nassir El-Jabi Noyan Turkkan Daniel Caissie 《American Journal of Climate Change》 2013年第2期106-115,共10页
The impacts of climate change on the discharge regimes in New Brunswick (Canada) were analyzed, using artificial neural network models. Future climate data were extracted from the Canadian Coupled General Climate Mode... The impacts of climate change on the discharge regimes in New Brunswick (Canada) were analyzed, using artificial neural network models. Future climate data were extracted from the Canadian Coupled General Climate Model (CGCM3.1) under the greenhouse gas emission scenarios B1 and A2 defined by the Intergovernmental Panel on Climate Change (IPCC). The climate change fields (temperatures and precipitation) were downscaled using the delta change approach. Using the artificial neural network, future river discharge was predicted for selected hydrometric stations. Then, a frequency analysis was carried out using the Generalized Extreme Value (GEV) distribution function, where the parameters of the distribution were estimated using L-moments method. Depending on the scenario and the time slice used, the increase in low return floods was about 30% and about 15% for higher return floods. Low flows showed increases of about 10% for low return droughts and about 20% for higher return droughts. An important part of the design process using frequency analysis is the estimation of future change in floods or droughts under climate scenarios at a given site and for specific return periods. This was carried out through the development of Regional Climate Index (RCI), linking future floods and droughts to their frequencies under climate scenarios B1 and A2. 展开更多
关键词 CANADIAN CLIMATE model Artificial NEURAL Networks Floods droughtS REGIONAL CLIMATE index
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Spatially Explicit Modeling of Long-Term Drought Impacts on Crop Production in Austria
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作者 Franziska Strauss Elena Moltchanova Erwin Schmid 《American Journal of Climate Change》 2013年第3期1-11,共11页
Droughts have serious and widespread impacts on crop production with substantial economic losses. The frequency and severity of drought events may increase in the future due to climate change. We have developed three ... Droughts have serious and widespread impacts on crop production with substantial economic losses. The frequency and severity of drought events may increase in the future due to climate change. We have developed three meteorological drought scenarios for Austria in the period 2008-2040. The scenarios are defined based on a dry day index which is combined with bootstrapping from an observed daily weather dataset of the period 1975-2007. The severity of long-term drought scenarios is characterized by lower annual and seasonal precipitation amounts as well as more significant temperature increases compared to the observations. The long-term impacts of the drought scenarios on Austrian crop production have been analyzed with the biophysical process model EPIC (Environmental Policy Integrated Climate). Our simulation outputs show that—for areas with historical mean annual precipitation sums below 850 mm— already slight increases in dryness result in significantly lower crop yields i.e. depending on the drought severity, between 0.6% and 0.9% decreases in mean annual dry matter crop yields per 1.0% decrease in mean annual precipitation sums. The EPIC results of more severe droughts show that spring and summer precipitation may become a limiting factor in crop production even in regions with historical abundant precipitation. 展开更多
关键词 LONG-TERM drought modeling Dry DAY index BIOPHYSICAL IMPACTS Spatial Variability EPIC Austria
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Future Changes in Drought Characteristics over Southern South America Projected by a CMIP5 Multi-Model Ensemble
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作者 Olga C. Penalba Juan A. Rivera 《American Journal of Climate Change》 2013年第3期173-182,共10页
The impact of climate change on drought main characteristics was assessed over Southern South America. This was done through the precipitation outputs from a multi-model ensemble of 15 climate models of the Coupled Mo... The impact of climate change on drought main characteristics was assessed over Southern South America. This was done through the precipitation outputs from a multi-model ensemble of 15 climate models of the Coupled Model Intercomparison Project Phase 5 (CMIP5). The Standardized Precipitation Index was used as a drought indicator, given its temporal flexibility and simplicity. Changes in drought characteristics were identified by the difference for early (2011-2040) and late (2071-2100) 21st century values with respect to the 1979-2008 baseline. In order to evaluate the multi-model outputs, model biases were identified through a comparison with the drought characteristics from the Global Precipitation Climatology Centre database for the baseline period. Future climate projections under moderate and high-emission scenarios showed that the occurrence of short-term and long-term droughts will be more frequent in the 21st century, with shorter durations and greater severities over much of the study area. These changes in drought characteristics are independent on the scenario considered, since no significant differences were observed on drought changes. The future changes scenario might be even more dramatic, taking into account that in most of the region the multi-model ensemble tends to produce less number of droughts, with higher duration and lower severity. Therefore, drought contingency plans should take these results into account in order to alleviate future water shortages that can have significant economic losses in the agricultural and water resources sectors of Southern South America. 展开更多
关键词 CMIP5 models drought Standardized PRECIPITATION index CLIMATE Change SOUTHERN SOUTH AMERICA
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Estimating the Yield Loss of Winter Wheat from Drought in the United States Southern Plains Region as Influenced by El Niño-Southern Oscillation (ENSO)
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作者 Prem Woli Gerald R. Smith +1 位作者 Charles R. Long Francis M. Rouquette, Jr. 《Agricultural Sciences》 2024年第9期1018-1034,共17页
Wheat (Triticum aestivum L.) production is a major economic activity in most regional and rural areas in the Southern Plains, a semi-arid region of the United States. This region is vulnerable to drought and is projec... Wheat (Triticum aestivum L.) production is a major economic activity in most regional and rural areas in the Southern Plains, a semi-arid region of the United States. This region is vulnerable to drought and is projected to experience a drier climate in the future. Since the interannual variability in climate in this region is linked to an ocean-atmospheric phenomenon, called El Niño-Southern Oscillation (ENSO), droughts in this region may be associated with ENSO. Droughts that occur during the critical growth phases of wheat can be extremely costly. However, the losses due to an impending drought can be minimized through mitigation measures if it is predicted in advance. Predicting the yield loss from an imminent drought is crucial for stakeholders. One of the reliable ways for such prediction is using a plant physiology-based agricultural drought index, such as Agricultural Reference Index for Drought (ARID). This study developed ENSO phase-specific, ARID-based models for predicting the drought-induced yield loss for winter wheat in this region by accounting for its phenological phase-specific sensitivity to drought. The reasonable values of the drought sensitivity coefficients of the yield model for each ENSO phase (El Niño, La Niña, or Neutral) indicated that the yield models reflected reasonably well the phenomena of water stress decreasing the winter wheat yields in this region during different ENSO phases. The values of various goodness-of-fit measures used, including the Nash-Sutcliffe Index (0.54 to 0.67), the Willmott Index (0.82 to 0.89), and the percentage error (20 to 26), indicated that the yield models performed fairly well at predicting the ENSO phase-specific loss of wheat yields from drought. This yield model may be useful for predicting yield loss from drought and scheduling irrigation allocation based on the phenological phase-specific sensitivity to drought as impacted by ENSO. 展开更多
关键词 ARID drought drought index ENSO El Niño Growth-Stage model Phenological-Phase Prediction Semi-Arid Wheat Yield Loss
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Resilience, reliability and risk analyses of maize, sorghum and sunflower in rain-fed systems using a soil moisture modeling approach 被引量:1
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作者 Berhanu F. Alemaw 《Agricultural Sciences》 2012年第1期114-123,共10页
This paper is aimed at examining the applicability of methods for resilience, reliability and risk analyses of rain-fed agricultural systems from modeled continuous soil moisture availability in rain-fed crop lands. T... This paper is aimed at examining the applicability of methods for resilience, reliability and risk analyses of rain-fed agricultural systems from modeled continuous soil moisture availability in rain-fed crop lands. The methodology involves integration of soil and climatic data in a simple soil moisture accounting model to assess soil moisture availability, and a risk used as indicator of sustainability of rain-fed agricultural systems. It is also attempted to demonstrate the role of soil moisture modeling in risk analysis and agricultural water management in a semi-arid region in Limpopo Basin where rain-fed agriculture is practiced. For this purpose, a daily-time step soil moisture accounting model is employed to simulate daily soil moisture, evaporation, surface runoff, and deep percolation using 40 years (1961-2000) of agroclimatic data, and cropping cycle data of maize, sorghum and sunflower. Using a sustainability criterion on crop water requirement and soil moisture availability, we determined resilience, risk and reliability as a quantitative measure of sustainability of rain-fed agriculture of these three crops. These soil moisture simulations and the sustainability criteria revealed further confirmation of the relative sensitivity to drought of these crops. Generally it is found that the risk of failure is relatively low for sorghum and relatively high for maize and sunflower in the two sites with some differences of severity of failure owing to the slightly different agroclimatic settings. 展开更多
关键词 RESILIENCE RELIABILITY Risk Analysis: Agricultural drought index Rain-Fed Agriculture Soil Moisture modeling Limpopo Basin
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Projected Warming and Occurrence of Meteorological Droughts—Insights from the Coasts of South India
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作者 Dhanya Praveen A. Ramachandran 《American Journal of Climate Change》 2015年第2期173-179,共7页
The latest development in the climate change forecast, using regional climate models, made it possible to provide more detailed information on the future changes in the climatic variables in the face of global warming... The latest development in the climate change forecast, using regional climate models, made it possible to provide more detailed information on the future changes in the climatic variables in the face of global warming. The PRECIS, UK Met office Hadley Centre’s Regional Climate Model is being used in simulating the future climate corresponding to the IPCC-SRES A1B emission scenario for the period 2040-2070 with reference to the base line year 1970-2000 for coastal region of Thiruvallur, South India. The results indicated a significant increase in the mean maximum temperature, mean minimum temperature and a slight decrease in the precipitation over the study area. The outcomes of the IMD method of Percent Deviation analysis show that the Thiruvallur has witnessed moderate to mild droughts during the period 1970 to 2011. Moderate drought years were mainly 1974, 1980, 1982 and 1999 with -35.78%, -30.09%, -30.54%, -27.30% rainfall deviations respectively. SPI-12 is also employed to analyze the occurrence and severity of drought events in the past. The analysis revealed that the year 1974 with SPI value -2.05 was the extremely severe drought year on record during the period 1970-2011. The years 1982 (-1.7), 1980 (-1.67), 1999 (-1.48) were severe dry years. Pearson’s correlation analysis proved that both the outputs have significant positive correlation (0.05 level) with R2 value of 0.992. It is necessary to develop early warning systems and apt drought preparedness strategies to cope with this natural hazard. 展开更多
关键词 Global WARMING drought Standardised Precipitation index CLIMATE Change Regional CLIMATE modelling Impacts
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基于多源遥感数据与模型对比的冬小麦土壤含水量区域监测研究
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作者 吴东丽 刘聪 +5 位作者 郭超凡 丁明明 吴苏 阙艳红 姜明梁 李雁 《中国农学通报》 2024年第25期147-154,共8页
实时、精准的土壤水分含量监测是农业用水管理的基础,探究冬小麦土壤水分反演的最优模型对于提高农业用水效率和可持续发展均具有重要的意义。本研究以河南省鹤壁市浚县冬小麦种植区域的土壤水分含量为研究对象,采用无人机遥感数据、卫... 实时、精准的土壤水分含量监测是农业用水管理的基础,探究冬小麦土壤水分反演的最优模型对于提高农业用水效率和可持续发展均具有重要的意义。本研究以河南省鹤壁市浚县冬小麦种植区域的土壤水分含量为研究对象,采用无人机遥感数据、卫星遥感数据、田间采样数据,分别运用温度植被干旱指数模型、水云模型和改进的水云模型3种方法,进行土壤含水量反演对比分析与最优模型选择。结果表明,3种方法中10 cm深度的反演精度均高于20 cm,且R^(2)均大于0.4。其中采用改进的水云模型方法在10 cm深度的R^(2)为0.7055、RMSE为0.0209,20 cm深度的R^(2)为0.5069、RMSE为0.0271,优于水云模型和温度植被干旱指数的反演效果。因此,改进的水云模型是一种适合用于麦田土壤水分反演的方法,它能够提供较高的反演精度。 展开更多
关键词 冬小麦 土壤水分含量监测 土壤水分反演 反演精度 无人机遥感 卫星遥感 温度植被干旱指数模型 水云模型
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土壤水分数据融合及其在旱涝灾害多维度评估中的应用 被引量:1
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作者 张蕾 郭安红 +3 位作者 宋迎波 何亮 赵晓凤 赵运成 《农业工程学报》 EI CAS CSCD 北大核心 2024年第13期68-76,共9页
获取高精度的土壤相对湿度对开展土壤墒情和旱涝精细化监测评估和预报预警有重要意义。该研究基于2020–2023年4–11月中国气象局陆面数据同化系统(China Meteorological Administration Land Data Assimilation System,CLDAS)逐日土壤... 获取高精度的土壤相对湿度对开展土壤墒情和旱涝精细化监测评估和预报预警有重要意义。该研究基于2020–2023年4–11月中国气象局陆面数据同化系统(China Meteorological Administration Land Data Assimilation System,CLDAS)逐日土壤相对湿度、全国土壤水分自动站逐小时土壤相对湿度以及土地利用类型、土壤属性、地理信息等数据,采用随机森林和支持向量机模型构建土壤水分自动站观测和CLDAS反演的土壤相对湿度动态融合订正模型,基于融合的土壤相对湿度构建土壤旱涝强度-面积-时间多维度评估指数,开展多维度旱涝监测评估。结果表明:1)采用随机森林模型融合后,0~10、0~20、0~50 cm土壤相对湿度与观测的土壤相对湿度的决定系数分别为0.79、0.81、0.80,相对均方根误差分别为13.81%、11.40%、9.50%,优于支持向量机模型。2)全国土壤缺墒日数百分率呈东南至西北增加趋势,内蒙古中西部、西北地区大部普遍在70%、甚至80%以上,内蒙古东南部、华北中北部、西南地区中西部为50%~70%,中东部大部在40%以下;土壤过湿日数百分率呈东南至西北减小趋势,华南东部和南部、西南地区南部、东北地区东北部多数在50%以上。3)基于融合土壤相对湿度数据构建的土壤缺墒、土壤过湿、墒情指数以及旱涝面积、持续时间指数,明显提升了2022年长江流域高温干旱、2023年台风“杜苏芮”和“卡努”等典型灾害性天气过程动态评估的定量化、精细化水平。土壤湿度融合数据及其旱涝评估指数可有效助力旱涝灾害多维度精细化定量评估,为防灾减灾提供重要支撑。 展开更多
关键词 模型 土壤 相对湿度 旱涝指数 随机森林 支持向量机
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长江流域旱涝急转演变特征及其社会经济暴露度 被引量:1
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作者 孟长青 董子娇 +2 位作者 王远坤 张余庆 钟德钰 《水力发电学报》 CSCD 北大核心 2024年第4期34-49,共16页
旱涝急转是指干旱和洪水之间的快速转变,对农业生产和人类安全造成巨大威胁。本研究基于月尺度的旱涝急转量级指数,分析了长江流域历史和未来四种旱涝急转事件,并通过滑窗法构建了旱涝急转量级的时变函数,揭示了未来旱涝急转风险变化。... 旱涝急转是指干旱和洪水之间的快速转变,对农业生产和人类安全造成巨大威胁。本研究基于月尺度的旱涝急转量级指数,分析了长江流域历史和未来四种旱涝急转事件,并通过滑窗法构建了旱涝急转量级的时变函数,揭示了未来旱涝急转风险变化。同时,结合共享社会经济路径量化了人口和经济受旱涝急转风险变化影响的程度。结果显示,历史时期长江流域中下游旱涝急转事件频发,旱–涝和涝–旱事件每10年发生10~12次,而旱–涝–旱和涝–旱–涝事件每10年发生3~4次。未来旱–涝–旱和涝–旱–涝事件预计大幅增加,其中长江上游部分地区增长了约7倍。对于历史基准期50年一遇的旱涝急转事件,未来发生概率将增加5~10倍,给长江流域的人口和经济带来重大影响。 展开更多
关键词 旱涝急转 标准化降水蒸散指数 第六次国际耦合模式比较计划 人口暴露 长江流域
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PSO-SVR模型在吉林省干旱指数预测中的应用
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作者 徐子曦 钟闻宇 唐友 《智慧农业导刊》 2024年第11期11-15,共5页
随着气候变暖程度愈加严重,干旱问题成为我国农业生产的一大威胁,严重妨碍我国农业生产的发展,因此掌握科学预测干旱指数的技术,可以为未来旱情提供预防建议,防止旱情进一步扩大,进而保障粮食安全。基于吉林省40个地区的气压、气温、降... 随着气候变暖程度愈加严重,干旱问题成为我国农业生产的一大威胁,严重妨碍我国农业生产的发展,因此掌握科学预测干旱指数的技术,可以为未来旱情提供预防建议,防止旱情进一步扩大,进而保障粮食安全。基于吉林省40个地区的气压、气温、降水量和相对湿度等多个气象因子及SPEI指数,对其未来干旱指数进行预测,比较BP模型、RF模型、SVR模型及经过优化的PSO-SVR模型的4个误差指标,发现PSO-SVR模型表现最为优异,R2达到0.964,MSE达到0.021,优于其他3个模型,拟合效果更为显著。结果显示,PSO-SVR模型在吉林省SPEI指数的预测中表现出极高的可行性和准确性,其出色的性能为吉林省的防旱减灾研究提供强有力的理论支持。 展开更多
关键词 SPEI SVR 预测模型 干旱指数 回归分析
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基于EMD-GWO-LSTM模型的新疆标准化降水蒸散指数预测方法研究
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作者 许超杰 窦燕 孟琪琳 《干旱区研究》 CSCD 北大核心 2024年第4期527-539,共13页
干旱预测一直是干旱研究领域的重大挑战,提高干旱预测的准确性是解决干旱问题的关键。基于1961—2019年新疆34个气象站点月降水和月平均气温数据,计算得到标准化降水蒸散指数(Standardized Precipitation Evapotranspiration Index,SPE... 干旱预测一直是干旱研究领域的重大挑战,提高干旱预测的准确性是解决干旱问题的关键。基于1961—2019年新疆34个气象站点月降水和月平均气温数据,计算得到标准化降水蒸散指数(Standardized Precipitation Evapotranspiration Index,SPEI),对新疆气象干湿变化进行分析,提出一种经验模态分解方法(empirical mode decomposition,EMD)-灰狼优化算法(grey wolf optimizer,GWO)-长短期神经网络(long short-term memory network,LSTM)的数据分解型干旱组合预测模型进行预测,并进行模型性能评价。结果表明:(1)干旱周期性变化整体呈现平稳且周期长的特点;(2)EMD能够有效优化数据的平稳性,GWO优化预测模型参数,组合模型的预测精度相较于单一预测模型有明显提高;(3)4个预测模型结果精度由高到低的排序为:EMD-GWO-LSTM、GWO-LSTM、GWO-支持向量回归(Support Vactor Regression,SVR)、LSTM,拟合优度分别为0.972、0.939、0.862、0.830,EMD-GWO-LSTM组合预测模型的预测精度优于其余3个预测模型。EMD-GWO-LSTM组合模型可有效提高气象干旱的预测精度,为新疆地区气象干旱预报及抗旱减灾工作提供了新的方法手段。 展开更多
关键词 EMD-GWO-LSTM模型 标准化降水蒸散指数 干旱预测 新疆
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MODIS数据的干旱监测模型研究 被引量:46
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作者 谭德宝 刘良明 +1 位作者 鄢俊洁 胡艳 《长江科学院院报》 CSCD 北大核心 2004年第3期11-15,共5页
对地观测卫星(ESO)中分辨率成像光谱仪(MODIS)传感器因其具有高时间分辨率、高光谱分辨率、适中的空间分辨率等特点,非常适合大范围、长时期、动态的干旱监测。借鉴以往的各种干旱监测方法,提出了一个基于MODIS的综合性干旱监测模型。... 对地观测卫星(ESO)中分辨率成像光谱仪(MODIS)传感器因其具有高时间分辨率、高光谱分辨率、适中的空间分辨率等特点,非常适合大范围、长时期、动态的干旱监测。借鉴以往的各种干旱监测方法,提出了一个基于MODIS的综合性干旱监测模型。该模型纳入与干旱有关的各种参数,并且首次将云指数作为一个重要参数引入模型。通过2003年湖北干旱的实例验证了此模型,结果显示此模型能很好的用于干旱预警与监测。 展开更多
关键词 MODIS数据 干旱监测 干旱等级 干旱模型
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灌区干旱风险评估模型研究 被引量:30
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作者 王晓红 乔云峰 +2 位作者 沈荣开 尹正杰 胡铁松 《水科学进展》 EI CAS CSCD 北大核心 2004年第1期77-81,共5页
根据风险理论,建立了包括农业干旱发生概率、抗旱能力、受灾体种植面积比等多因子的灌区农业干旱风险评估模型。并将相对产量作为灌区农业干旱评估指标,能够反映土壤 作物 大气系统中水分运动对农业生产的影响,利用该指标结合干旱风险... 根据风险理论,建立了包括农业干旱发生概率、抗旱能力、受灾体种植面积比等多因子的灌区农业干旱风险评估模型。并将相对产量作为灌区农业干旱评估指标,能够反映土壤 作物 大气系统中水分运动对农业生产的影响,利用该指标结合干旱风险评估模型对灌区农业干旱进行风险评估,分析出灌区各种作物对干旱风险度影响最大的生育阶段和风险度最高的农作物,以便灌区制定合理的抗旱方案以减小灌区干旱损失。 展开更多
关键词 灌区 干旱 风险评估模型 农作物
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Palmer旱度模式在渭北旱塬泾惠渠灌区的应用研究 被引量:5
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作者 刘招 燕爱玲 乔长录 《干旱地区农业研究》 CSCD 北大核心 2010年第3期259-264,共6页
依据泾惠渠灌区的水文气象历史资料,应用待定系数和回归方法,建立了适用于泾惠渠灌区的Palmer旱度模式。将该旱度模式应用于灌区干旱系列特征分析,分析结果给出不同干旱程度可能发生的频率及年内分布,验证了灌区有较明显的旱化倾向及冬... 依据泾惠渠灌区的水文气象历史资料,应用待定系数和回归方法,建立了适用于泾惠渠灌区的Palmer旱度模式。将该旱度模式应用于灌区干旱系列特征分析,分析结果给出不同干旱程度可能发生的频率及年内分布,验证了灌区有较明显的旱化倾向及冬灌期和春灌期大旱的出现机率较大等特征,这些均与灌区多年来的实际干旱情况相符,表明了所建立的Palmer旱度模式合理,具有较明确的物理意义且能够反映灌区的干旱特征。 展开更多
关键词 干旱 Palmer旱度模式 干旱指数 泾惠渠灌区
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基于PDSI指数的三江源干旱气候特征分析 被引量:15
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作者 刘蕊蕊 陆宝宏 +3 位作者 陈昱潼 董闯 阮晓波 唐文涛 《人民黄河》 CAS 北大核心 2013年第6期59-62,66,共5页
根据三江源地区12个气象站点1971—2004年的气象资料,利用修正的Palmer旱度模式,计算分析了三江源地区PDSI指数的时空变化特征,并采用Morlet小波变换系数分析了PDSI指数的变化周期。结果表明:三江源地区有变干趋势,但变化趋势不显著,其... 根据三江源地区12个气象站点1971—2004年的气象资料,利用修正的Palmer旱度模式,计算分析了三江源地区PDSI指数的时空变化特征,并采用Morlet小波变换系数分析了PDSI指数的变化周期。结果表明:三江源地区有变干趋势,但变化趋势不显著,其中黄河源显著变干对三江源变干影响较大;三江源地区干旱发生年份与厄尔尼诺现象出现的年份基本相近;三江源地区西北较干旱、东南较湿润;经小波分析,三江源PDSI指数大约有20 a的第一主变化周期,与太阳双黑子活动周期相近,在20 a周期内还包括11~12 a和6 a的小周期;三江源干旱化与气候变暖、降水减少密切相关,尤其是夏、秋两季。 展开更多
关键词 Palmer旱度模式 PDSI指数 小波分析 干旱特征 三江源
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青海夏季干旱特征及其预测模型研究 被引量:16
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作者 戴升 李林 +2 位作者 刘彩红 时兴合 杨延华 《冰川冻土》 CSCD 北大核心 2012年第6期1433-1440,共8页
利用1961—2008年青海非干旱区(除柴达木盆地)地面气象观测资料、74个环流特征量、海温资料、北半球500hPa高度场网格点资料以及500hPa高度场遥相关,对夏季干旱的变化趋势和干旱发生的机理进行了研究.结果表明:1961—2008年夏季青海省... 利用1961—2008年青海非干旱区(除柴达木盆地)地面气象观测资料、74个环流特征量、海温资料、北半球500hPa高度场网格点资料以及500hPa高度场遥相关,对夏季干旱的变化趋势和干旱发生的机理进行了研究.结果表明:1961—2008年夏季青海省非干旱区、东部农业区分别发生干旱15a、18a,发生干旱的年几率为31.3%、37.5%;东部农业区发生干旱的几率较大,中轻度干旱发生几率大于特大、重度干旱.夏季典型干旱年500hPa欧亚中高纬度上空高度距平分布为正距平,极涡偏弱;非干旱年蒙古到青藏高原上由负距平控制,极涡偏强,偏向东半球,印缅低压槽十分活跃.当夏季西大西洋型、上年秋季欧亚纬向环流指数偏弱,而4月西太平洋型偏强,8月青藏高原地面加热场强度距平指数偏强,夏季容易发生干旱;反之,当夏季西大西洋型、上年秋季欧亚纬向环流指数偏强,而4月西太平洋型偏弱,8月青藏高原地面加热场强度距平指数偏弱,则夏季不易发生夏季干旱.1961—2008年模拟方程的准确率为83.3%,2009—2010年预测结果与实况接近,趋势预测准确. 展开更多
关键词 夏季 干旱指数(SPI) 环流 关系 模型
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水文干旱指标研究进展综述 被引量:25
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作者 胡彩虹 王金星 +1 位作者 王艺璇 李勇 《人民长江》 北大核心 2013年第7期11-15,共5页
随着气候变化及其极端气候事件的频繁出现,对抗击干旱灾害的决策服务能力和管理水平提出了更高要求。在介绍干旱研究的背景、干旱基本状况及其分类的基础上,系统总结了国内外水文干旱指标及干旱预警等级的研究成果。分析了我国水文干旱... 随着气候变化及其极端气候事件的频繁出现,对抗击干旱灾害的决策服务能力和管理水平提出了更高要求。在介绍干旱研究的背景、干旱基本状况及其分类的基础上,系统总结了国内外水文干旱指标及干旱预警等级的研究成果。分析了我国水文干旱研究存在的不足,以及将来可能的研究方向,建立了以反映机理分布式水文模型为主的一主多辅综合性水文干旱指标。分析表明,建立以旱限水位为干旱预警的全国干旱预警体系是今后的发展方向。 展开更多
关键词 干旱 水文干旱指标 分布式水文模型 综述
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灌区农业干旱评估指标分析及应用 被引量:19
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作者 王晓红 胡铁松 +1 位作者 吴凤燕 樊建锋 《中国农村水利水电》 北大核心 2003年第7期4-6,共3页
主要对三种农业干旱指标 ,即降水量指标、供需水关系指标和Palmer干旱指标进行评述 ,并对三种指标进行实例应用。应用结果表明 ,Palmer干旱指标可以更准确地评估灌区的干旱情况。
关键词 降水量 灌区 干旱 评估模型 农作物
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