[ Objective] The aim was to introduce the breeding process of natural colorful cocoon silkworm variety, Chuancan No. 24. [ Method] By cross breeding and pedigree separation, the silkworm variety, Chuancan No. 24, with...[ Objective] The aim was to introduce the breeding process of natural colorful cocoon silkworm variety, Chuancan No. 24. [ Method] By cross breeding and pedigree separation, the silkworm variety, Chuancan No. 24, with double sex-limited markings and strong vitality and for sum- mer-Autumn rearing was bred. [ Result] The results of laboratory identification and countryside test in Sichuan Province indicated that the Chuancan No. 24 was strong and could be reared easily. They had uniform development and excellent quality of cocoon and silk. In addition, their sexes could be identified by larval body color and markings. The main indexes are as follows： cocoon yield per 10 003 fourth instar larvae, 19.66 kg; filament length, 1 241.29 m; length of non-broken filament, 941.99 mm; reelability, 75.87% ; raw silk ratio of fresh cocoon, 17.07% ; and neatness, 94.03 points. The main economic features of new variety were better than those of the control. [ Conclusion] The Chuancan No. 24 has been approved by the Sichuan Silkworm Evaluation Commission, and it is suitable to rear this new variety in some regions of the Yangtze River drainage basin, such as Sichuan Province and Chongqing.展开更多
From summer to autumn in 2022,a severe drought lasted in southern China,posing serious effects on economic growth and ecological systems.This study explored the atmospheric circulations accounting for this persistent ...From summer to autumn in 2022,a severe drought lasted in southern China,posing serious effects on economic growth and ecological systems.This study explored the atmospheric circulations accounting for this persistent drought event.It shows that the drought in southern China during the summer of 2022 was strongly linked to the divergence of water vapor flux and descending motions,which were respectively caused by the anomalous anticyclone over the western North Pacific and the northward movement of the East Asian subtropical jet(EASJ).Differently,the atmospheric background responsible for the sustained drought in autumn is manly featured by a cyclonic circulation anomaly over the region from the Bay of Bengal to the South China Sea,which led to decreased moisture and descending motions in southern China.Further investigation suggests that the rarely strong surface warming over northern Eurasia and the extreme La Nina-like pattern over the tropical Pacific jointly resulted in the anomalous anticyclone over the western North Pacific and the northward shift of the EASJ in the summer of 2022,while the cyclonic circulation anomaly prevailing over the region from the Bay of Bengal to the South China Sea in autumn was largely attributed to the extremely negative anomalies of the tropical Indian Ocean sea surface temperature.展开更多
汉江流域是中国重要的调水水源区,研究其降水特征对防涝抗旱具有重要意义。基于汉江流域62个国家气象站降水资料及美国国家环境预报中心/国家大气研究中心(National Center for Envi⁃ronmental Prediction/National Center for Atmosphe...汉江流域是中国重要的调水水源区,研究其降水特征对防涝抗旱具有重要意义。基于汉江流域62个国家气象站降水资料及美国国家环境预报中心/国家大气研究中心(National Center for Envi⁃ronmental Prediction/National Center for Atmospheric Research,NCEP/NCAR)再分析资料,通过百分位数、相关分析和T-N波作用通量,探讨了2021年伏秋(8—10月)连汛期间汉江降水的季内差异特征及其与大气环流和海温的关系。结果表明:2021年伏秋期间,汉江上游流域出现破纪录降水,极端性强、总量大。降水在伏夏和秋季两个时段均偏多,但秋季的多雨区位置更偏北。伏夏期间,北大西洋经西伯利亚向东频散的Rossby波使得欧亚上空维持“两槽两脊”,冷空气较强,同时西太平洋副热带高压(简称“副高”)强势西伸,通过西南和偏东两支通道向北输送暖湿水汽;冷暖空气在高空急流南侧对峙并辐合上升,导致降水异常偏多。秋季,北太平洋频散的Rossby波使得欧亚上空维持“两槽一脊”,冷空气较弱;副高断裂导致水汽通道偏南,高空急流北抬使冷暖空气辐合上升位置偏北,造成雨区偏北。2021年汉江流域伏夏降水异常受热带东大西洋海温正异常影响,秋季受赤道中太平洋冷海温影响。展开更多
基金funded by the Agricultural Science and Technology Achievements Transformation Fund Programs (2010GB2F000412)
文摘[ Objective] The aim was to introduce the breeding process of natural colorful cocoon silkworm variety, Chuancan No. 24. [ Method] By cross breeding and pedigree separation, the silkworm variety, Chuancan No. 24, with double sex-limited markings and strong vitality and for sum- mer-Autumn rearing was bred. [ Result] The results of laboratory identification and countryside test in Sichuan Province indicated that the Chuancan No. 24 was strong and could be reared easily. They had uniform development and excellent quality of cocoon and silk. In addition, their sexes could be identified by larval body color and markings. The main indexes are as follows： cocoon yield per 10 003 fourth instar larvae, 19.66 kg; filament length, 1 241.29 m; length of non-broken filament, 941.99 mm; reelability, 75.87% ; raw silk ratio of fresh cocoon, 17.07% ; and neatness, 94.03 points. The main economic features of new variety were better than those of the control. [ Conclusion] The Chuancan No. 24 has been approved by the Sichuan Silkworm Evaluation Commission, and it is suitable to rear this new variety in some regions of the Yangtze River drainage basin, such as Sichuan Province and Chongqing.
基金supported by the National Natural Science Foundation of China(Grant No.42025502)。
文摘From summer to autumn in 2022,a severe drought lasted in southern China,posing serious effects on economic growth and ecological systems.This study explored the atmospheric circulations accounting for this persistent drought event.It shows that the drought in southern China during the summer of 2022 was strongly linked to the divergence of water vapor flux and descending motions,which were respectively caused by the anomalous anticyclone over the western North Pacific and the northward movement of the East Asian subtropical jet(EASJ).Differently,the atmospheric background responsible for the sustained drought in autumn is manly featured by a cyclonic circulation anomaly over the region from the Bay of Bengal to the South China Sea,which led to decreased moisture and descending motions in southern China.Further investigation suggests that the rarely strong surface warming over northern Eurasia and the extreme La Nina-like pattern over the tropical Pacific jointly resulted in the anomalous anticyclone over the western North Pacific and the northward shift of the EASJ in the summer of 2022,while the cyclonic circulation anomaly prevailing over the region from the Bay of Bengal to the South China Sea in autumn was largely attributed to the extremely negative anomalies of the tropical Indian Ocean sea surface temperature.
文摘汉江流域是中国重要的调水水源区,研究其降水特征对防涝抗旱具有重要意义。基于汉江流域62个国家气象站降水资料及美国国家环境预报中心/国家大气研究中心(National Center for Envi⁃ronmental Prediction/National Center for Atmospheric Research,NCEP/NCAR)再分析资料,通过百分位数、相关分析和T-N波作用通量,探讨了2021年伏秋(8—10月)连汛期间汉江降水的季内差异特征及其与大气环流和海温的关系。结果表明:2021年伏秋期间,汉江上游流域出现破纪录降水,极端性强、总量大。降水在伏夏和秋季两个时段均偏多,但秋季的多雨区位置更偏北。伏夏期间,北大西洋经西伯利亚向东频散的Rossby波使得欧亚上空维持“两槽两脊”,冷空气较强,同时西太平洋副热带高压(简称“副高”)强势西伸,通过西南和偏东两支通道向北输送暖湿水汽;冷暖空气在高空急流南侧对峙并辐合上升,导致降水异常偏多。秋季,北太平洋频散的Rossby波使得欧亚上空维持“两槽一脊”,冷空气较弱;副高断裂导致水汽通道偏南,高空急流北抬使冷暖空气辐合上升位置偏北,造成雨区偏北。2021年汉江流域伏夏降水异常受热带东大西洋海温正异常影响,秋季受赤道中太平洋冷海温影响。
文摘目的探究灵芝菌固态发酵下夏秋梅占红茶的风味特征。方法采用高效液相色谱法(high performance liquid chromatography,HPLC)、电子舌(electronic tongue,E-tongue)与气相色谱-质谱法(gas chromatography-mass spectrometry,GC-MS)相结合,利用多元统计分析,对夏秋梅占灵芝菌茶的滋味与香气品质特征进行判定。结果与夏秋梅占红茶相比,梅占灵芝菌茶在滋味与香气特征上具有差异,HPLC检测结果显示儿茶素类、咖啡碱类苦涩味物质及部分氨基酸类物质含量显著下降,电子舌结果表明甜味响应值增加,苦味、鲜味响应值降低。其中梅占灵芝菌茶中脯氨酸、没食子酸、儿茶素没食子酸与苦味特性呈显著负相关,天冬氨酸、丙氨酸与涩味特性呈显著负相关,丙氨酸与鲜味特性呈极显著正相关,没食子儿茶素与鲜味特性呈显著正相关。挥发性成分上,建立正交偏最小二乘法-判别分析(orthogonal partial least squares-discriminant analysis,OPLS-DA)模型,选取模型中变量重要性投影(variable importance in the projection,VIP)值>1的香气化合物作为关键香气差异特征化合物,经筛选共得到48个,其中酮类6个,醛类9个,醇类15个,酯类7个,酸类化3个,其他芳烯类、呋喃等烷烃类8个,共有8个化合物相对含量上升,40个化合物相对含量下降。结论在灵芝菌影响下,对夏秋梅占红茶滋味与香气特征具有改善作用,此研究为夏秋茶的品质改善与多元化利用提供了新路径。
