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高光谱的病害棉叶光合参数提取 被引量:5
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作者 陈兵 王刚 +3 位作者 刘景德 马占鸿 王静 李天南 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2018年第6期1834-1838,共5页
应用高光谱遥感监测黄萎病胁迫下棉花叶片光合参数。在350~2 500nm光谱波段获取207个不同时期不同病情严重度的棉叶样本光谱数据,同步利用光合仪测量样本光合参数。采用单因素方差和相关分析研究光合参数特征,提取样本叶片光合参数的敏... 应用高光谱遥感监测黄萎病胁迫下棉花叶片光合参数。在350~2 500nm光谱波段获取207个不同时期不同病情严重度的棉叶样本光谱数据,同步利用光合仪测量样本光合参数。采用单因素方差和相关分析研究光合参数特征,提取样本叶片光合参数的敏感波段并筛选光谱特征参数,采用线性和非线性回归方法建立预测模型并检验。结果表明:随病情严重度增加,棉叶净光合速率、气孔导度、蒸腾速率均下降,胞间CO_2浓度先降后增,差异显著;病情严重度与光合参数均达到显著相关,与净光合速率、蒸腾速率、气孔导度、胞间CO_2浓度相关系数分别为-0.97,-0.957,-0.886和0.715。选择与光合参数相关性最好的光谱敏感波段R704,R706,R699,R690,FD688,FD732,FD690,FD731,FD681组建新的光谱特征参数并与传统参数一起对净光合速率、蒸腾速率、气孔导度和胞间CO_2浓度进行反演,其中是以光谱参数PRI[FD732,FD688]),R706,RVI[890,670]),R690为自变量建立的净光合速率、蒸腾速率、气孔导度和胞间CO_2浓度反演方程精度最高,预测R^2分别为0.827,0.810,0.658,0.573;RMSE分别为5.466,2.801,109.500,63.500;RE分别为0.041,0.137,0.158,0.021。表明通过高光谱遥感可以实现棉花黄萎病叶片光合生理参数的提取。 展开更多
关键词 棉花 黄萎病 叶片 光合参数 高光谱 模型
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不同配置模式下机采棉脱叶催熟视觉症状及机理 被引量:4
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作者 张国蕾 陈兵 +5 位作者 刘景德 王静 余渝 韩焕勇 王方永 李天南 《新疆农业科学》 CAS CSCD 北大核心 2019年第10期1783-1793,共11页
【目的】分析机采棉脱叶和吐絮视觉症状和影响因素,研究不同脱叶剂在棉田的脱叶催熟规律,为脱叶剂在新疆早熟棉区的推广和应用提供科学依据。【方法】设置不同脱叶剂处理,在每个处理内外行选择长势均匀的棉株进行挂牌调查,分析取样叶和... 【目的】分析机采棉脱叶和吐絮视觉症状和影响因素,研究不同脱叶剂在棉田的脱叶催熟规律,为脱叶剂在新疆早熟棉区的推广和应用提供科学依据。【方法】设置不同脱叶剂处理,在每个处理内外行选择长势均匀的棉株进行挂牌调查,分析取样叶和棉铃。【结果】叶片脱落的先后顺序是上层先掉小叶、新叶,后掉大叶、老叶、主茎叶,间隔3~5 d;中下层先掉主茎叶、大叶、老叶,后掉其他叶,间隔3~5 d;整体棉株主茎叶、铃对位叶先脱落,其他叶片,如铃上位叶、铃下位叶后脱落,间隔3~5 d。棉铃吐絮顺序是自下而上,内行快于外行1~2 d。叶片脱落过程中叶片颜色由绿色4~5 d后变成褐红色再过3~4 d后变成黄色,形态上由正常4~5 d后形成斑点,4~5 d后斑点连片,再过4~5 d后整叶老化干枯。离层在喷药后3~5 d先从下部裂开,再过3~5 d后断裂,形成完整离层。叶片脱落和棉铃吐絮顺序受到棉花品种(生育期121~125 d)、配置(66 cm+10 cm或76 cm+76 cm)、施药时间(9月5~15日)、药剂浓度(225~525 mL/hm 2)、药剂种类、温度(日均温>18℃,最低温度>12℃)、雨、风(>3级)、草害、病虫害、支撑点(>1)及外界碰撞等内外因素的影响。【结论】喷药后3~5 d开始出现脱叶和吐絮加快症状,20 d后脱叶基本稳定,脱叶率83%~99%以上,吐絮率增加到81%以上。 展开更多
关键词 棉花 脱叶剂 脱叶吐絮规律 视觉症状 影响因素
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Effects of planting patterns on yield, quality, and defoliation in machine-harvested cotton 被引量:16
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作者 WANG Fang-yong HAN Huan-yong +6 位作者 LIN Hai CHEN Bing KONG Xian-hui NING Xin-zhu WANG Xu-wen YU Yu liu jing-de 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2019年第9期2019-2028,共10页
The aim of this study was to elucidate the effects of different machine-harvested cotton-planting patterns on defoliation,yield,and fiber quality in cotton and to provide support for improving the quality of machine-h... The aim of this study was to elucidate the effects of different machine-harvested cotton-planting patterns on defoliation,yield,and fiber quality in cotton and to provide support for improving the quality of machine-harvested cotton.In the 2015 and 2016 growing seasons,the Xinluzao 45(XLZ45)and Xinluzao 62(XLZ62)cultivars,which are primarily cultivated in northern Xinjiang,were used as study materials.Conventional wide-narrow row(WNR),wide and ultra-narrow row(UNR),wide-row spacing with high density(HWR),and wide-row spacing with low density(LWR)planting patterns were used to assess the effects of planting patterns on defoliation,yield,and fiber quality.Compared with WNR,the seed cotton yields were significantly decreased by 2.06–5.48%for UNR and by 2.50–6.99%for LWR,respectively.The main cause of reduced yield was a reduction in bolls per unit area.The variation in HWR yield was–1.07–1.07%with reduced bolls per unit area and increased boll weight,thus demonstrating stable production.In terms of fiber quality indicators,the planting patterns only showed significant effects on the micronaire value,with wide-row spacing patterns showing an increase in the micronaire values.The defoliation and boll-opening results showed that the number of leaves and dried leaves in HWR was the lowest among the four planting patterns.Prior to the application of defoliating agent and before machine-harvesting,the numbers of leaves per individual plant in HWR were decreased by 14.45 and 25.00%on average,respectively,compared with WNR,while the number of leaves per unit area was decreased by 27.44 and 36.21%on average,respectively.The rates of boll-opening and defoliation in HWR were the highest.Specifically,the boll-opening rate before defoliation and machine-harvesting in HWR was 44.54 and 5.94%higher on average than in WNR,while the defoliation rate prior to machine-harvesting was 3.45%higher on average than in WNR.The numbers of ineffective defoliated leaves and leaf trash in HWR were the lowest,decreased by 33.40 and 32.43%,respectively,compared with WNR.In conclusion,the HWR planting pattern is associated with a high and stable yield,does not affect fiber quality,promotes early maturation,and can effectively decrease the amount of leaf trash in machine-picked seed cotton,and thus its use is able to improve the quality of machine-harvested cotton. 展开更多
关键词 machine-harvested COTTON PLANTING PATTERNS DEFOLIATION YIELD QUALITY
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多排抗滑桩在大型滑坡治理中的工程应用研究 被引量:12
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作者 赵军 刘静德 梁志荣 《建筑科学》 CSCD 北大核心 2020年第S01期156-161,共6页
结合南京某滑坡治理工程,探讨多排抗滑桩在大型滑坡治理工程中的应用。通过对边坡及建筑变形监测结果,分析确定大型滑坡的潜在滑裂面,并通过反分析确定滑带土的力学参数,为滑坡治理设计提供依据。采用多排抗滑桩进行大型滑坡治理,能有... 结合南京某滑坡治理工程,探讨多排抗滑桩在大型滑坡治理工程中的应用。通过对边坡及建筑变形监测结果,分析确定大型滑坡的潜在滑裂面,并通过反分析确定滑带土的力学参数,为滑坡治理设计提供依据。采用多排抗滑桩进行大型滑坡治理,能有效防治不同模式的滑坡破坏。对于滑面较长、下滑力较大的滑坡,采取多排抗滑桩加固能有效减少抗滑桩所受滑坡推力,改善抗滑桩受力性能,确保边坡的安全与稳定。 展开更多
关键词 抗滑桩 滑坡治理 滑坡推力 强度折减法 稳定性分析
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