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植被生态自动化观测仪器的设计与实现 被引量:1
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作者 王贝贝 姚艳丽 +2 位作者 张争 王苗苗 郭琰煊 《安徽农业科学》 CAS 2021年第17期201-205,共5页
研究植被生态自动化观测方法,进而确定仪器的组成结构,根据传感器的接口、协议类型和神经网络处理器的应用方式设计了基于ARM架构控制处理器的外设接口,进一步结合非RKNN模型的转换应用流程,设计了控制处理器数据采集、处理、存储、传... 研究植被生态自动化观测方法,进而确定仪器的组成结构,根据传感器的接口、协议类型和神经网络处理器的应用方式设计了基于ARM架构控制处理器的外设接口,进一步结合非RKNN模型的转换应用流程,设计了控制处理器数据采集、处理、存储、传输和控制交互的具体功能和流程。针对3种不同的植被类型,将仪器分别部署在内蒙古、广西和安徽3个国家级农业气象试验基地,采用仪器测量数据与人工平行观测的方法进行外场试验。结果表明,这种植被生态自动化观测方法是可行的、有效的,仪器性能指标也符合实际业务观测要求。 展开更多
关键词 植被生态自动化观测 深度学习 植被关键特征参数测量
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基于多视角反射光谱的冬小麦冠层叶片氮素营养监测研究 被引量:9
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作者 肖春华 李少昆 +3 位作者 王克如 卢艳丽 谢瑞芝 高世菊 《作物学报》 CAS CSCD 北大核心 2007年第7期1141-1145,共5页
通过2个蛋白质含量不同的冬小麦品种和4个氮素水平的试验,研究传感器在垂直冬小麦垄平面上,冠层不同观测角度的反射光谱与叶片氮素营养的关系,改进小麦冠层氮素光谱诊断的理论与方法。结果表明,在本试验选择的7种植被指数光谱特征参量... 通过2个蛋白质含量不同的冬小麦品种和4个氮素水平的试验,研究传感器在垂直冬小麦垄平面上,冠层不同观测角度的反射光谱与叶片氮素营养的关系,改进小麦冠层氮素光谱诊断的理论与方法。结果表明,在本试验选择的7种植被指数光谱特征参量中,2个小麦品种均表现为比值植被指数(RVI[670,890])与冠层叶片氮素含量(CLNC)相关性最高;不同视角的RVI与冠层叶片氮素含量关系中,0°、30°和90°的相关性最高;利用0°、30°和90°的RVI与CLNC进行模型拟合,其模型的决定系数是0°>30°>90°;在建立的0°模型中,京411小麦模型RMSE为0.2915,预测准确率为90.2%,中优9507模型RMSE为0.3827,预测准确率为87.2%。本研究证明改变反射光谱观测角度,能够提高冠层叶片氮素含量的光谱预测精度,不同小麦品种其光谱特征与冠层叶片氮素含量关系不同,在应用中要根据不同的小麦品种建立相应的模型。 展开更多
关键词 冠层叶片氮素含量(CLNC) 观测角度比值植被指数(RVI) 模型 冬小麦
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植被日光诱导叶绿素荧光高光谱成像仪研究(特邀)
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作者 于磊 汪涛 林静 《激光与光电子学进展》 CSCD 北大核心 2024年第2期227-235,共9页
植被日光诱导叶绿素荧光是一种可以表征植被光合生产力的重要衡量指标。为了实现对植被日光诱导叶绿素荧光的广域精准探测,设计并研制了一种叶绿素荧光高光谱成像探测仪。该成像探测仪使用了基于棱镜-体相位全息透射光栅的全透射式光学... 植被日光诱导叶绿素荧光是一种可以表征植被光合生产力的重要衡量指标。为了实现对植被日光诱导叶绿素荧光的广域精准探测,设计并研制了一种叶绿素荧光高光谱成像探测仪。该成像探测仪使用了基于棱镜-体相位全息透射光栅的全透射式光学系统,在高数值孔径(0.25)的基础上实现了高光学性能:可在20°视场和670~780 nm(可扩展至650~800 nm)工作波段实现1 mrad的空间角分辨率、0.3 nm的光谱分辨率和优于100的信噪比。由系统设计结果、样机测试结果和应用数据分析结果可知,样机完全满足设计要求。本仪器可为农林监测和碳循环观测提供重要的科学数据,并可作为陆地植被光合作用中有效的新型观测手段。 展开更多
关键词 植被观测 日光诱导叶绿素荧光 高光谱成像 体相位全息透射光栅
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Identification of habitat requirements of farmland birds based on a hierarchical structured monitoring scheme
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作者 Jrg HOFFMANN Udo WITTCHEN +1 位作者 Ulrich STACHOW Gert BERGER 《Chinese Birds》 CSCD 2013年第4期265-280,共16页
Agricultural landscapes are essential for the conservation of biodiversity. Nevertheless, a negative trend continues to be observed in many rural areas for the most prominent indicator species group, the farmland bird... Agricultural landscapes are essential for the conservation of biodiversity. Nevertheless, a negative trend continues to be observed in many rural areas for the most prominent indicator species group, the farmland birds. However, clear cause-effect relationships are rarely reported and sometimes difficult to deduce, especially from monitoring data which are based only on the detection of species and counts of the numbers of individuals. Because the identification of habitat preferences is a precondition for farmland bird biodiversity conservation efforts, a monitoring scheme for the simultaneous collection and analysis of bird and land use data was developed and tested. In order to assign the occurrence of bird species to land characteristics at various spatial scales and different land use and crop types, we applied a hierarchical structured sampling design. The spatial scales were ‘agricultural landscape', ‘agricultural landscape types', ‘field crops and other habitats' and ‘vegetation structures'. These scales were integrated with a novel concept, the ‘habitat matrix'(HM). This method was applied to farmland breeding bird abundances on 29 plots, each 1 km2 in size, by the use of the territory mapping method. The same plots were enlarged by a 100 m buffer and the sizes and location of habitats documented. Vegetation height, coverage and density were also recorded for all crop fields in the study area. We propose that this monitoring method facilitates the identification of scale dependent relationships between farmland bird habitat characteristics and bird abundance. This is demonstrated by the farmland bird species Corn Bunting(Emberiza calandra), Skylark(Alauda arvensis), and Whinchat(Saxicola rubetra). The breeding territories of these species reveal large differences within the various spatial scales ‘agricultural landscape', ‘agricultural landscape types' and ‘field crops'. Throughout the breeding season the abundances varied, dependent on the field crop and the development of vegetation structures(height, coverage, and density). HM-analysis led to the identification of specific habitat configurations preferred by individual bird species within the agricultural landscape. These findings indicate that the methodology has the potential to design monitoring schemes for the identification of cause-and-effects of landscape configuration, land use and land use changes on the habitat suitability and abundance of farmland birds. 展开更多
关键词 farmland birds hierarchical monitoring scheme agricultural landscape vegetation structures habitat matrix BIODIVERSITY
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