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GIS支持下的小麦区域化苗情遥感监测应用研究 被引量:4
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作者 张雪芬 陈怀亮 +1 位作者 邹春辉 陈东 《南京气象学院学报》 CSCD 1999年第1期116-120,共5页
在地理信息系统(GIS)支持下,将处理好的归一化植被指数(NVI)图与地形图、土壤质地图、政区图、年降水量图、年平均气温图、小麦生育期积温图等背景图件叠加,进行比较客观的小麦遥感生态分层,并制成常年非麦象元分布底图。... 在地理信息系统(GIS)支持下,将处理好的归一化植被指数(NVI)图与地形图、土壤质地图、政区图、年降水量图、年平均气温图、小麦生育期积温图等背景图件叠加,进行比较客观的小麦遥感生态分层,并制成常年非麦象元分布底图。在此基础上,根据地面监测网实地调查资料,建立了一套适合不同监测层的遥感监测指标。最后,将剔除常年非麦象元后的NVI图与遥感生态区分层图进行集成,采用不同指标划分小麦苗情等级,从而提高了小麦苗情遥感解译精度。 展开更多
关键词 小麦 苗情 域化 遥感 生态区分层 GIS
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The Ecological Distributions of N, P Utilizing Bacteria and Heterotrophic Bacteria in the Moderate Hypoxia Zone of the Changjiang Estuary
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作者 LIU Jingjing DU Ping +4 位作者 ZENG Jiangning CHEN Quanzhen SHOU Lu LIAO Yibo JIANG Zhibing 《Journal of Ocean University of China》 SCIE CAS 2013年第4期589-598,共10页
The distributions of N utilizing bacteria (denitrifying bacteria and ammonifying bacteria) ,P utilizing bacteria (organic phosphobacteria and inorganic phosphobacteria) and heterotrophic bacteria in the Changjiang Est... The distributions of N utilizing bacteria (denitrifying bacteria and ammonifying bacteria) ,P utilizing bacteria (organic phosphobacteria and inorganic phosphobacteria) and heterotrophic bacteria in the Changjiang Estuary,and the roles of main environmental factors in distributing bacteria,are explored with observations from two cruises in June and August 2006.Comparisons between the two important periods of initial hypoxia phase (June) and developed hypoxia phase (August) show differences in both bacterial distributions and the associated main environmental factors.First,the primary group of ammonifying bacteria has larger magnitude with spatial maximum value in the hypoxic stations related to sediment in August.The phosphobacterial abundance and detection rates in August are much lower than those in June,but the denitrifying bacterial abundance becomes greater in August.However,the difference of heterotrophic bacterial abundance between June and August is not obvious.Second,main environmental factors influencing bacteria vary from initial hypoxia phase to developed hypoxia phase.Two parameters (salinity and NO3) in surface water and five environmental parameters (pH,salinity,PO43,NO3and temperature) in bottom water and surface sediment play major roles in the bacterial abundance in June,while different parameter combinations (salinity and PO43) in surface water and different parameter combinations (DO,DOC,NO3,PO43 and pH) in bottom water and surface sediment play major roles in August.Moreover,the bottom bacteria distributions in area south of 31 N are related to the position of the Taiwan Warm Current in June.The bacterial abundance and distribution may respond to the environmental change in the hypoxia processes of initial phase and developed phase.During the hypoxia processes,the whole structure of bacterial functional groups probably turns to different states,causing the recycling of nutrient regeneration and aggravating hypoxia regionally. 展开更多
关键词 Changjiang Estuary HYPOXIA bacterial functional group
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