Using early indica rice Zhongzao 39 and japonica rice Xiushui 134 as the experimental materials, the effects of 4 temperature levels after transplantation on turning green, leaf growth, tillering, dry matter accumulat...Using early indica rice Zhongzao 39 and japonica rice Xiushui 134 as the experimental materials, the effects of 4 temperature levels after transplantation on turning green, leaf growth, tillering, dry matter accumulation and nutrition absorption were studied using a greenhouse and an artificial climate chest. We found that （1） tillering did not occur and growth of one new leaf took over 15 days at 16℃. New leaf growth took over 10 days and tillering occurred after 15 days of transplanta- tion at 19 ℃. Tillering appeared 10 days after planting and new leaf growth took 5 days between 22 and 25 ℃. This showed that low temperature impeded the turn- ing green of rice seedlings and the temperature must reach above 19 ℃ to ensure timely appearance of new leaf, tillering and turning green in rice seedlings. （2） When the temperature was 10 increased, both 100-seedling dry weight and nitrogen absorption increased. At temperatures lower 11 than 19 ℃, both dry weight incre- ment and nitrogen absorption were low. Nitrogen absorption of all organs increased obviously between 19 and 22 ℃. Thus, 19 ℃ was found to be an minimum tem- perature for plant organs to absorb nutrients. （3）Tiller of seedling cultivated on dry- land soil and substrate grew quickly and tillering occurred about 7 days after trans- planting. After that, the growth rate was about 0.18 tiller per day. For seedlings cultivated in slurry, tillering occurred 10 days after transplanting and the tillers grew at a rate of 0.16 tiller per day. However, substrate choice during the seedling rais- ing stage had no significant influence on leaf age. （4） Japonica rice exhibited stronger resistance to low temperature than indica rice. Tillering began at about the same time after transplanting in both rice varieties, but japonica rice exhibited higher tillering speed than early indica rice. The speed of leaf growth was higher in japoni- ca rice before transplantation but higher in indica rice after transplantation.展开更多
In order to investigate the effect of snow cover on alfalfa overwintering and turning green,6 different alfalfa varieties( including Longmu806,Gongnong No. 1,Aohan,Wega 7F,WL319 HQ,Caoyuan No. 3) were used as plant ma...In order to investigate the effect of snow cover on alfalfa overwintering and turning green,6 different alfalfa varieties( including Longmu806,Gongnong No. 1,Aohan,Wega 7F,WL319 HQ,Caoyuan No. 3) were used as plant materials. There were 4 treatments in this study include snow-cover of 0,30%,70% and natural snow-cover( used as control). Nutrient content and antioxidant enzyme activity of root were measured before and after overwintering period. The rate of plant returning green and growth rate after greening were also measured after turning green. The result showed that the snow cover was the guarantee of alfalfa safely overwintering and turning green. The 54. 5-77. 9 cm snowfall was the optimum thickness of snow for safe overwintering. Alfalfa improved the overwintering ability by enhancing the root nutrients and antioxidant enzyme activity,and it was affected by snow cover. In addition total nitrogen and soluble sugar increased by 61% and 60% respectively,soluble protein reduced by8%,SOD and CAT reduced by 20% and 9% respectively than that before the overwintering under 70% of natural snow-cover. There were differences between overwintering ability of 6 different alfalfa varieties,in which Caoyuan No. 3 has more grass production and Wega 7F has stronger overwintering ability.展开更多
Green cooling is an important technology in green manufacturing. In the way of jetting, cooling airflo-w in used in the experiments of metal material cutting, by comparison of the changes of some technological factors...Green cooling is an important technology in green manufacturing. In the way of jetting, cooling airflo-w in used in the experiments of metal material cutting, by comparison of the changes of some technological factors, such as cutting heat, surface finish, in the process of jet cooling, pour cooling and natural cooling, we can draiv the conclusion that air jet cooling has a better cooling effect and green function. It can be 'widely used in both traditional and automatic green manufacturing.展开更多
基金Supported by Special Scientific Research Funds for Commonweal Section(Agriculture)(201203029,201003016)China Rice Industry System Project(2011-2015)Special Funding for Basic Scientific Research and Zhejiang Provincial Natural Science Foundation(LY13C130004)~~
文摘Using early indica rice Zhongzao 39 and japonica rice Xiushui 134 as the experimental materials, the effects of 4 temperature levels after transplantation on turning green, leaf growth, tillering, dry matter accumulation and nutrition absorption were studied using a greenhouse and an artificial climate chest. We found that （1） tillering did not occur and growth of one new leaf took over 15 days at 16℃. New leaf growth took over 10 days and tillering occurred after 15 days of transplanta- tion at 19 ℃. Tillering appeared 10 days after planting and new leaf growth took 5 days between 22 and 25 ℃. This showed that low temperature impeded the turn- ing green of rice seedlings and the temperature must reach above 19 ℃ to ensure timely appearance of new leaf, tillering and turning green in rice seedlings. （2） When the temperature was 10 increased, both 100-seedling dry weight and nitrogen absorption increased. At temperatures lower 11 than 19 ℃, both dry weight incre- ment and nitrogen absorption were low. Nitrogen absorption of all organs increased obviously between 19 and 22 ℃. Thus, 19 ℃ was found to be an minimum tem- perature for plant organs to absorb nutrients. （3）Tiller of seedling cultivated on dry- land soil and substrate grew quickly and tillering occurred about 7 days after trans- planting. After that, the growth rate was about 0.18 tiller per day. For seedlings cultivated in slurry, tillering occurred 10 days after transplanting and the tillers grew at a rate of 0.16 tiller per day. However, substrate choice during the seedling rais- ing stage had no significant influence on leaf age. （4） Japonica rice exhibited stronger resistance to low temperature than indica rice. Tillering began at about the same time after transplanting in both rice varieties, but japonica rice exhibited higher tillering speed than early indica rice. The speed of leaf growth was higher in japoni- ca rice before transplantation but higher in indica rice after transplantation.
基金Supported by the Sixth Batch of Postdoctoral Special Funding Program in Heilongjiang Province(LBH-TZ06020)
文摘In order to investigate the effect of snow cover on alfalfa overwintering and turning green,6 different alfalfa varieties( including Longmu806,Gongnong No. 1,Aohan,Wega 7F,WL319 HQ,Caoyuan No. 3) were used as plant materials. There were 4 treatments in this study include snow-cover of 0,30%,70% and natural snow-cover( used as control). Nutrient content and antioxidant enzyme activity of root were measured before and after overwintering period. The rate of plant returning green and growth rate after greening were also measured after turning green. The result showed that the snow cover was the guarantee of alfalfa safely overwintering and turning green. The 54. 5-77. 9 cm snowfall was the optimum thickness of snow for safe overwintering. Alfalfa improved the overwintering ability by enhancing the root nutrients and antioxidant enzyme activity,and it was affected by snow cover. In addition total nitrogen and soluble sugar increased by 61% and 60% respectively,soluble protein reduced by8%,SOD and CAT reduced by 20% and 9% respectively than that before the overwintering under 70% of natural snow-cover. There were differences between overwintering ability of 6 different alfalfa varieties,in which Caoyuan No. 3 has more grass production and Wega 7F has stronger overwintering ability.
文摘Green cooling is an important technology in green manufacturing. In the way of jetting, cooling airflo-w in used in the experiments of metal material cutting, by comparison of the changes of some technological factors, such as cutting heat, surface finish, in the process of jet cooling, pour cooling and natural cooling, we can draiv the conclusion that air jet cooling has a better cooling effect and green function. It can be 'widely used in both traditional and automatic green manufacturing.
文摘利用1982年至2003年NASAGIMMS逐月归一化植被指数（NDVI）数据集和玛曲县气温、降水资料,对玛曲县近22年来NDVI变化和气候变化特征及其相互关系进行分析,以揭示黄河上游地区植被对全球变暖的区域响应.结果表明：（1）玛曲县植被变化在不同时段表现出较大差异,NDVI年际变化略有增加.（2）夏季是NDVI增长最快的季节,春季NDVI在20世纪90年代后期到本世纪初呈下降趋势,秋、冬季NDVI呈下降趋势.（3）返青期和NDVI值在春季达到同一水平值的时间及夏季达到峰值的时间逐年提前,说明生长季提前是该地区植被对全球变暖的主要响应表现.（4）玛曲县近22年来植被的NDVI变化在中等盖度水平（0.3～0.5）呈增加趋势,高盖度水平（≥0.7）的植被呈下降趋势,而在年代间变化水平上,气温和降水对植被生长都有影响,其中气温要比降水更显著;玛曲县降水和气温在季节尺度上对NDVI的影响不明显,除夏季气温与夏季NDVI关系密切之外,其他季节的关系均不明显.（5）按植被变化特点,将NDVI变化斜率最大值0.005定义为返青期指标,发现该地区牧草返青期的变化主要受温度条件影响,随气候变暖,返青期提前,其变化规律为4～5月份平均气温每10年升高0.6℃,返青期每10年提前3 d.
