叶绿素a浓度(Chlorophyll-a:Chl-a)是内陆水体重要的水质参数之一,遥感数据为其提供了大范围、多时相的监测信息,然而由于内陆湖泊水色要素复杂的光学性质及较大的时空差异,传统的遥感影像及单一的Chl-a反演模型在应用中存在着局限性。...叶绿素a浓度(Chlorophyll-a:Chl-a)是内陆水体重要的水质参数之一,遥感数据为其提供了大范围、多时相的监测信息,然而由于内陆湖泊水色要素复杂的光学性质及较大的时空差异,传统的遥感影像及单一的Chl-a反演模型在应用中存在着局限性。因此本研究以太湖为研究区,时间分辨率1小时的静止海洋水色卫星Geostationary Ocean Color Imager(GOCI)为数据源,在基于层次聚类法实现归一化实测光谱反射率分类的基础上,利用光谱角测距匹配实现2012年5月6日(08:16—15:16)8景GOCI太湖影像的水体分类;并针对不同水体类型分别建立基于GOCI影像的Chl-a反演模型,实现不同类型水体的Chl-a浓度反演。结果表明,太湖水体光谱可分为四类,类型1光谱体现出漂浮藻类的特征,可将其作为蓝藻水华的判定依据;类型2—4体现的特征分别为水体含有较高Chl-a浓度、较高悬浮物浓度及相对较低Chl-a较低悬浮物浓度;并且类型2—4与分类前相比,其分类模型估算的Chl-a浓度误差均得到了不同程度的提高,平均相对误差分别降低了7%,12.3%和15.9%;此外,GOCI影像反演结果不仅可以很好地反映Ch卜a浓度的空间分布状况,也能反映出太湖Chl-a浓度的日变化差异及规律,表现出了其在富营养化污染动态监测及预警中的应用潜力。该方法在GOCI影像中的应用,在提高Chl-a浓度反演精度的同时也提高了模型在实际应用中的适用性,为日后太湖水体不同时刻Chl-a浓度的精确估算提供了基础。展开更多
The genus Oryza consists of approximately 24 species with 10 recognized genome types (A, B, C, BC, CD, E, F, G, HJ, HK). The species with the CD genome are endemic to the Central and South America and comprise three s...The genus Oryza consists of approximately 24 species with 10 recognized genome types (A, B, C, BC, CD, E, F, G, HJ, HK). The species with the CD genome are endemic to the Central and South America and comprise three species, i.e. O. latifolia Desv., O. alta Swallen and O. grandiglumis (Doell) Prod. Although the three species can be easily distinguished from the species with the other genomes in Oryza by their morphological characteristics, it is very difficult to distinguish them from one another. Recent studies suggested that O. alta and O. grandiglumis should be the same species (O. grandigiumis), whereas O. latifolia retains its taxonomic position unchangeably. In this paper, a total of 77 clones of the nuclear ribosomal internal transcribed spacer (ITS) from 11 samples representing different geographical races were sequenced. Using DNA Strider 1.2 software, the restriction enzyme digestion sites of these clone sequences were analyzed. Based on restriction fragment length polymorphism (RFLP) of ITS sequences, a method to identify the species with CD genome in Oryza was proposed. The method is rapid and convenient and all experimental procedure includes only three steps: (1) to amplify the ITS fragment with the routine primers; (2) to digest PCR products with restriction enzymes Fok I and Dra III or both; (3) to run the digested product on 1% agarose gel and identify the sample based on the restriction profiles.展开更多
文摘叶绿素a浓度(Chlorophyll-a:Chl-a)是内陆水体重要的水质参数之一,遥感数据为其提供了大范围、多时相的监测信息,然而由于内陆湖泊水色要素复杂的光学性质及较大的时空差异,传统的遥感影像及单一的Chl-a反演模型在应用中存在着局限性。因此本研究以太湖为研究区,时间分辨率1小时的静止海洋水色卫星Geostationary Ocean Color Imager(GOCI)为数据源,在基于层次聚类法实现归一化实测光谱反射率分类的基础上,利用光谱角测距匹配实现2012年5月6日(08:16—15:16)8景GOCI太湖影像的水体分类;并针对不同水体类型分别建立基于GOCI影像的Chl-a反演模型,实现不同类型水体的Chl-a浓度反演。结果表明,太湖水体光谱可分为四类,类型1光谱体现出漂浮藻类的特征,可将其作为蓝藻水华的判定依据;类型2—4体现的特征分别为水体含有较高Chl-a浓度、较高悬浮物浓度及相对较低Chl-a较低悬浮物浓度;并且类型2—4与分类前相比,其分类模型估算的Chl-a浓度误差均得到了不同程度的提高,平均相对误差分别降低了7%,12.3%和15.9%;此外,GOCI影像反演结果不仅可以很好地反映Ch卜a浓度的空间分布状况,也能反映出太湖Chl-a浓度的日变化差异及规律,表现出了其在富营养化污染动态监测及预警中的应用潜力。该方法在GOCI影像中的应用,在提高Chl-a浓度反演精度的同时也提高了模型在实际应用中的适用性,为日后太湖水体不同时刻Chl-a浓度的精确估算提供了基础。
文摘The genus Oryza consists of approximately 24 species with 10 recognized genome types (A, B, C, BC, CD, E, F, G, HJ, HK). The species with the CD genome are endemic to the Central and South America and comprise three species, i.e. O. latifolia Desv., O. alta Swallen and O. grandiglumis (Doell) Prod. Although the three species can be easily distinguished from the species with the other genomes in Oryza by their morphological characteristics, it is very difficult to distinguish them from one another. Recent studies suggested that O. alta and O. grandiglumis should be the same species (O. grandigiumis), whereas O. latifolia retains its taxonomic position unchangeably. In this paper, a total of 77 clones of the nuclear ribosomal internal transcribed spacer (ITS) from 11 samples representing different geographical races were sequenced. Using DNA Strider 1.2 software, the restriction enzyme digestion sites of these clone sequences were analyzed. Based on restriction fragment length polymorphism (RFLP) of ITS sequences, a method to identify the species with CD genome in Oryza was proposed. The method is rapid and convenient and all experimental procedure includes only three steps: (1) to amplify the ITS fragment with the routine primers; (2) to digest PCR products with restriction enzymes Fok I and Dra III or both; (3) to run the digested product on 1% agarose gel and identify the sample based on the restriction profiles.
