One of the study objectives of global change is land use/cover change (LUCC) by using multiscale remotely sensed data on global and regional scale. In this paper, field sample, digital camera, Landsat-ETM+ (ETM+, Enha...One of the study objectives of global change is land use/cover change (LUCC) by using multiscale remotely sensed data on global and regional scale. In this paper, field sample, digital camera, Landsat-ETM+ (ETM+, Enhanced Thematic Mapper) image and the National Oceanic and Atmospheric Administration/the advanced very high resolution radiometer (NOAA/AVHRR) image were integrated to detect, simulate and analyze the vegetation fractional coverage of typical steppe in northern China. The results show: (1) Vegetation fractional coverage measured by digital camera is more precise than results measured by other methods. It can be used to validate other measuring results. (2) Vegetation fractional coverage measured by 1 m 2 field sample change fluctuantly for different observers and for different sample areas. In this experiment, the coverage is generally high compared with the result measured by digital camera, and the average absolute error is 9.92%, but two groups measure results, correlation coefficient r(2) = 0.89. (3) Three kinds of methods using remotely sensed data were adopted to simulate the vegetation fractional coverage. Average absolute errors of the vegetation fractional coverage, measured by ETM+ and NOAA, are respectively 7.03% and 7.83% compared with the result measured by digital camera. When NOAA pixel was decomposed by ETM+ pixels after geometrical registry, the average absolute errors measured by this method is 5.68% compared with the digital camera result. Correction coefficients of three results with digital camera result r(2) are respectively 0.78, 0.61 and 0.76. (4) The result of statistic model established by NOAA-NDVI (NDVI, Normalized Difference Vegetation Index) and the vegetation fractional coverage measured by digital camera show lower precision (r(2) = 0.65) than the result of statistic model established by ETM+-NDVI and digital camera coverage then converted to NOAA image (r(2) = 0.80). Pixel decomposability method improves the precision of measuring the vegetation fractional coverage on a large scale. This is a significant practice on scaling by using remotely sensed data. Integrated application of multi-scale remotely sensed data in earth observation will be an important approach to promoting measuring precision of ecological parameters.展开更多
草原毛虫(Gynaephora ruergensis Chou et yin)是我国高原牧草中的一种有害害虫。草原毛虫核型多角体病毒新分离株(EupsNPV-Gr)具有典型的杆状病毒特征,呈单粒包埋型病毒粒子,ODV颗粒呈不规则的多边形,直径为1.0μm~1.35μm。EupsNPV-G...草原毛虫(Gynaephora ruergensis Chou et yin)是我国高原牧草中的一种有害害虫。草原毛虫核型多角体病毒新分离株(EupsNPV-Gr)具有典型的杆状病毒特征,呈单粒包埋型病毒粒子,ODV颗粒呈不规则的多边形,直径为1.0μm~1.35μm。EupsNPV-Gr能有效杀灭草原毛虫幼虫,它对草原毛虫的半致死浓度LC_(50)为4×10^(4)PIB/mL,是一种理想的生物防治剂。本研究对第一个EupsNPV-Gr基因组进行了测序和鉴定。EupsNPV-Gr基因组全长140684bp,包含134个开放阅读框。它与茶毛虫核型多角体病毒(EupsNPV)关系最为密切,序列同源性高达99%。系统进化分析表明,EupsNPV-Gr属于杆状病毒科alpha杆状病毒属,根据公认的种属划分标准,EupsNPV-Gr是EupsNPV的一个株系。新报道的基因组为研究该物种毒力的分子机制提供了基础。展开更多
文摘One of the study objectives of global change is land use/cover change (LUCC) by using multiscale remotely sensed data on global and regional scale. In this paper, field sample, digital camera, Landsat-ETM+ (ETM+, Enhanced Thematic Mapper) image and the National Oceanic and Atmospheric Administration/the advanced very high resolution radiometer (NOAA/AVHRR) image were integrated to detect, simulate and analyze the vegetation fractional coverage of typical steppe in northern China. The results show: (1) Vegetation fractional coverage measured by digital camera is more precise than results measured by other methods. It can be used to validate other measuring results. (2) Vegetation fractional coverage measured by 1 m 2 field sample change fluctuantly for different observers and for different sample areas. In this experiment, the coverage is generally high compared with the result measured by digital camera, and the average absolute error is 9.92%, but two groups measure results, correlation coefficient r(2) = 0.89. (3) Three kinds of methods using remotely sensed data were adopted to simulate the vegetation fractional coverage. Average absolute errors of the vegetation fractional coverage, measured by ETM+ and NOAA, are respectively 7.03% and 7.83% compared with the result measured by digital camera. When NOAA pixel was decomposed by ETM+ pixels after geometrical registry, the average absolute errors measured by this method is 5.68% compared with the digital camera result. Correction coefficients of three results with digital camera result r(2) are respectively 0.78, 0.61 and 0.76. (4) The result of statistic model established by NOAA-NDVI (NDVI, Normalized Difference Vegetation Index) and the vegetation fractional coverage measured by digital camera show lower precision (r(2) = 0.65) than the result of statistic model established by ETM+-NDVI and digital camera coverage then converted to NOAA image (r(2) = 0.80). Pixel decomposability method improves the precision of measuring the vegetation fractional coverage on a large scale. This is a significant practice on scaling by using remotely sensed data. Integrated application of multi-scale remotely sensed data in earth observation will be an important approach to promoting measuring precision of ecological parameters.
文摘草原毛虫(Gynaephora ruergensis Chou et yin)是我国高原牧草中的一种有害害虫。草原毛虫核型多角体病毒新分离株(EupsNPV-Gr)具有典型的杆状病毒特征,呈单粒包埋型病毒粒子,ODV颗粒呈不规则的多边形,直径为1.0μm~1.35μm。EupsNPV-Gr能有效杀灭草原毛虫幼虫,它对草原毛虫的半致死浓度LC_(50)为4×10^(4)PIB/mL,是一种理想的生物防治剂。本研究对第一个EupsNPV-Gr基因组进行了测序和鉴定。EupsNPV-Gr基因组全长140684bp,包含134个开放阅读框。它与茶毛虫核型多角体病毒(EupsNPV)关系最为密切,序列同源性高达99%。系统进化分析表明,EupsNPV-Gr属于杆状病毒科alpha杆状病毒属,根据公认的种属划分标准,EupsNPV-Gr是EupsNPV的一个株系。新报道的基因组为研究该物种毒力的分子机制提供了基础。
