Climate change will have important implications in water shore regions,such as Huang-Huai-Hai(3H) plain,where expected warmer and drier conditions might augment crop water demand.Sensitivity analysis is important in...Climate change will have important implications in water shore regions,such as Huang-Huai-Hai(3H) plain,where expected warmer and drier conditions might augment crop water demand.Sensitivity analysis is important in understanding the relative importance of climatic variables to the variation in reference evapotranspiration(ET 0).In this study,the 51-yr ET 0 during winter wheat and summer maize growing season were calculated from a data set of daily climate variables in 40 meteorological stations.Sensitivity maps for key climate variables were estimated according to Kriging method and the spatial pattern of sensitivity coefficients for these key variables was plotted.In addition,the slopes of the linear regression lines for sensitivity coefficients were obtained.Results showed that ET 0 during winter wheat growing season accounted for the largest proportion of annual ET 0,due to its long phenological days,while ET 0 was detected to decrease significantly with the magnitude of 0.5 mm yr-1in summer maize growing season.Solar radiation is considered to be the most sensitive and primarily controlling variable for negative trend in ET 0 for summer maize season,and higher sensitive coefficient value of ET 0 to solar radiation and temperature were detected in east part and southwest part of 3H plain respectively.Relative humidity was demonstrated as the most sensitive factor for ET 0 in winter wheat growing season and declining relativity humidity also primarily controlled a negative trend in ET 0,furthermore the sensitivity coefficient to relative humidity increased from west to southeast.The eight sensitivity centrals were all found located in Shandong Province.These ET 0 along with its sensitivity maps under winter wheat-summer maize rotation system can be applied to predict the agricultural water demand and will assist water resources planning and management for this region.展开更多
Crop consumptive water use is recognized as a key element to understand regional water management performance. This study documents an attempt to apply a regional evapotranspiration model(SEBAL) and crop information...Crop consumptive water use is recognized as a key element to understand regional water management performance. This study documents an attempt to apply a regional evapotranspiration model(SEBAL) and crop information for assessment of regional crop(summer maize and winter wheat) actual evapotranspiration(ET a) in Huang-Huai-Hai(3H) Plain, China. The average seasonal ET a of summer maize and winter wheat were 354.8 and 521.5 mm respectively in 3H Plain. A high-ET a belt of summer maize occurs in piedmont plain, while a low ET a area was found in the hill-irrigable land and dry land area. For winter wheat, a high-ET a area was located in the middle part of 3H Plain, including low plain-hydropenia irrigable land and dry land, hill-irrigable land and dry land, and basin-irrigable land and dry land. Spatial analysis demonstrated a linear relationship between crop ET a, normalized difference vegetation index(NDVI), and the land surface temperature(LST). A stronger relationship between ET a and NDVI was found in the metaphase and last phase than other crop growing phase, as indicated by higher correlation coefficient values. Additionally, higher correlation coefficients were detected between ET a and LST than that between ET a and NDVI, and this significant relationship ran through the entire crop growing season. ET a in the summer maize growing season showed a significant relationship with longitude, while ET a in the winter wheat growing season showed a significant relationship with latitude. The results of this study will serve as baseline information for water resources management of 3H Plain.展开更多
Link-up between farmers and supermarket is a new move adopted actively by the current government, conducive to consumers, farmers and circulation enterprises. At present, link-up between farmers and supermarket is lau...Link-up between farmers and supermarket is a new move adopted actively by the current government, conducive to consumers, farmers and circulation enterprises. At present, link-up between farmers and supermarket is launched in China's 15 provinces and cities, which will set off the revolution in the field of agricultural circulation. Based on the current situation of link-up between farmers and supermarket and the existing problems, we put forth the following recommendations: promoting the quality of farmers' cooperative organizations; establishing the logistics center of fresh agricultural products; using economies of scale to reduce the fresh logistics costs; improving the operation and management level of fresh agricultural products in supermarket.展开更多
基金supported by the Key Technologies R&D Program of China during the 12th Five-Year Plan period(2012BAD09B01)the National 973 Program of China(2012CB955904)the Project of Food Security and Climate Change in the Asia-Pacific Region:Evaluating Mismatch between Crop Development and Water Availability and Project of National Non-profit Institute Fund,China-Australia(BSRF201206)
文摘Climate change will have important implications in water shore regions,such as Huang-Huai-Hai(3H) plain,where expected warmer and drier conditions might augment crop water demand.Sensitivity analysis is important in understanding the relative importance of climatic variables to the variation in reference evapotranspiration(ET 0).In this study,the 51-yr ET 0 during winter wheat and summer maize growing season were calculated from a data set of daily climate variables in 40 meteorological stations.Sensitivity maps for key climate variables were estimated according to Kriging method and the spatial pattern of sensitivity coefficients for these key variables was plotted.In addition,the slopes of the linear regression lines for sensitivity coefficients were obtained.Results showed that ET 0 during winter wheat growing season accounted for the largest proportion of annual ET 0,due to its long phenological days,while ET 0 was detected to decrease significantly with the magnitude of 0.5 mm yr-1in summer maize growing season.Solar radiation is considered to be the most sensitive and primarily controlling variable for negative trend in ET 0 for summer maize season,and higher sensitive coefficient value of ET 0 to solar radiation and temperature were detected in east part and southwest part of 3H plain respectively.Relative humidity was demonstrated as the most sensitive factor for ET 0 in winter wheat growing season and declining relativity humidity also primarily controlled a negative trend in ET 0,furthermore the sensitivity coefficient to relative humidity increased from west to southeast.The eight sensitivity centrals were all found located in Shandong Province.These ET 0 along with its sensitivity maps under winter wheat-summer maize rotation system can be applied to predict the agricultural water demand and will assist water resources planning and management for this region.
基金supported by the National Key Technologies R&D Program of China during the 12th Five-Year Plan period (2012BAD09B01)the National Basic Research Program of China (973 Program, 2012CB955904)the National Science Foundation for Young Scientists of China (41401510)
文摘Crop consumptive water use is recognized as a key element to understand regional water management performance. This study documents an attempt to apply a regional evapotranspiration model(SEBAL) and crop information for assessment of regional crop(summer maize and winter wheat) actual evapotranspiration(ET a) in Huang-Huai-Hai(3H) Plain, China. The average seasonal ET a of summer maize and winter wheat were 354.8 and 521.5 mm respectively in 3H Plain. A high-ET a belt of summer maize occurs in piedmont plain, while a low ET a area was found in the hill-irrigable land and dry land area. For winter wheat, a high-ET a area was located in the middle part of 3H Plain, including low plain-hydropenia irrigable land and dry land, hill-irrigable land and dry land, and basin-irrigable land and dry land. Spatial analysis demonstrated a linear relationship between crop ET a, normalized difference vegetation index(NDVI), and the land surface temperature(LST). A stronger relationship between ET a and NDVI was found in the metaphase and last phase than other crop growing phase, as indicated by higher correlation coefficient values. Additionally, higher correlation coefficients were detected between ET a and LST than that between ET a and NDVI, and this significant relationship ran through the entire crop growing season. ET a in the summer maize growing season showed a significant relationship with longitude, while ET a in the winter wheat growing season showed a significant relationship with latitude. The results of this study will serve as baseline information for water resources management of 3H Plain.
基金Supported by Humanities and Social Sciences Youth Project of theMinistry of Education in 2010 (10YJC790234)
文摘Link-up between farmers and supermarket is a new move adopted actively by the current government, conducive to consumers, farmers and circulation enterprises. At present, link-up between farmers and supermarket is launched in China's 15 provinces and cities, which will set off the revolution in the field of agricultural circulation. Based on the current situation of link-up between farmers and supermarket and the existing problems, we put forth the following recommendations: promoting the quality of farmers' cooperative organizations; establishing the logistics center of fresh agricultural products; using economies of scale to reduce the fresh logistics costs; improving the operation and management level of fresh agricultural products in supermarket.
文摘目的系统评价肺癌患者并发肺部真菌感染的危险因素.方法系统检索CNKI、Wanfang、VIP、CBM、PubMed、Embase和The Cochrane Library,搜集有关肺癌患者并发肺部真菌感染危险因素的病例-对照研究和队列研究.检索时限从2007年1月-2022年10月.由2名研究者独立进行文献筛选、资料提取和质量评价,采用Rev Man 5.3软件进行Meta分析.结果共检索到24篇符合纳入与排除标准的文献,共计7349例肺癌患者.对18个潜在危险因素进行Meta分析,结果显示,年龄≥60岁、体力活动状态(PS)评分≥2分、吸烟史、高血压、糖尿病、贫血、TNM分期为Ⅲ-Ⅳ期、放疗、放化疗、侵入性操作、住院时间>14天、使用糖皮质激素和使用抗菌药物是肺癌患者发生肺部真菌感染的危险因素(均P<0.05).结论肺癌患者发生肺部真菌感染危险因素较多.早期识别肺癌患者发生肺部真菌感染的危险因素,并制定防治措施,有利于降低肺部真菌感染发病率.受纳入文献数量和质量限制,上述结论需要更多高质量研究予以验证.