PEG/Hoagland(-0.1 MPa)溶液根际胁迫处理5叶期玉米幼苗24h,明显刺激第5幼叶生长区细胞H?的分泌,比对照高约1.5倍,钒酸钠对此过程有强烈抑制作用。用水溶性多聚物(PEG4000/Dextran T 500)两相分配法分离玉米第5幼叶生长区的质膜,胁迫处...PEG/Hoagland(-0.1 MPa)溶液根际胁迫处理5叶期玉米幼苗24h,明显刺激第5幼叶生长区细胞H?的分泌,比对照高约1.5倍,钒酸钠对此过程有强烈抑制作用。用水溶性多聚物(PEG4000/Dextran T 500)两相分配法分离玉米第5幼叶生长区的质膜,胁迫处理增加了质膜H^+—ATPase对底物的亲和力,K_m降低到对照的?;活力增加约1.5倍。亚胺环己酮对胁迫处理引起的质膜H^+—ATP_(ase)活性增加没有抑制作用,不同程度的胁迫处理会导致膜制剂磷脂/蛋白比率的变化,其比率在0.83～1.05之间时.随比率的增加,质膜 H^+—ATP_(ase)活性迅速上升;比率在1.05～1.37之间时,随比率值增加,活性迅速下降。暗示质膜的磷脂含量变化可能是胁迫导致质膜 H^+—ATP_(ase)活性增加的主要原因。展开更多
Water footprint of production can be used to identify pressure on national or regional water resources generated by production activities. Water stress is defined as the ratio of water use （the difference between a r...Water footprint of production can be used to identify pressure on national or regional water resources generated by production activities. Water stress is defined as the ratio of water use （the difference between a re- gional water footprint of production and a green water footprint） to renewable water resources available in a country or region. Water stress can be used to identify pressure on national or regional water resources generated by production activities. This paper estimates the water footprint of production and the water stress in China during the years 1985-2009. The result shows that China＇s water footprint of production increased from 781.58×109 m^3 in 1985 to 1109.76 × 10^9 m^3 in 2009. Mega-cities and regions with less agriculture production due to local climatic conditions （Tibet and Qinghai） had lower water footprint of production, while the provinces （Henan, Shandong） with higher agriculture production had higher footprint. Provinces with severe water stress increased from 6 in 1985 to 9 in 2009. High to severe water stress exists mainly in mega-cities and agricultural areas located in the downstream areas of the Yellow River and the Yangtze River in North and Central China. The outlook for water resources pressure in China is not optimistic, with areas of stress expanding from northern to southern of China.展开更多
基金National Key Technology Research and Development Program of China(2016YFC0503403)Projects of China geological survey(DD20160106)
文摘Water footprint of production can be used to identify pressure on national or regional water resources generated by production activities. Water stress is defined as the ratio of water use （the difference between a re- gional water footprint of production and a green water footprint） to renewable water resources available in a country or region. Water stress can be used to identify pressure on national or regional water resources generated by production activities. This paper estimates the water footprint of production and the water stress in China during the years 1985-2009. The result shows that China＇s water footprint of production increased from 781.58×109 m^3 in 1985 to 1109.76 × 10^9 m^3 in 2009. Mega-cities and regions with less agriculture production due to local climatic conditions （Tibet and Qinghai） had lower water footprint of production, while the provinces （Henan, Shandong） with higher agriculture production had higher footprint. Provinces with severe water stress increased from 6 in 1985 to 9 in 2009. High to severe water stress exists mainly in mega-cities and agricultural areas located in the downstream areas of the Yellow River and the Yangtze River in North and Central China. The outlook for water resources pressure in China is not optimistic, with areas of stress expanding from northern to southern of China.
