Please wait a minute...
img img
高级检索
地球科学进展  2009, Vol. 24 Issue (7): 784-792    DOI: 10.11867/j.issn.1001-8166.2009.07.0784
地面观测方案     
田块尺度作物辐射温度获取方法对比研究
康国婷,阎广建*,任华忠,王颢星,钱永刚
北京师范大学遥感科学国家重点实验室,地理学与遥感科学学院, 北京  100875
A Comparison of Different Ground-based Radiative Temperature Measurement Methods on the Field Patch Scale
Kang Guoting, Yan Guangjian, Ren Huazhong, Wang Haoxing, Qian Yonggang
State Key Laboratory of Remote Sensing Science, School of Geography, Beijing Normal University, Beijing  100875, China
 全文: PDF(1547 KB)  
摘要:

热像仪的优势在于可以获得组分辐射温度,常用于地面温度同步测量实验中,其数据与植被覆盖度联合还可以得到作物田块尺度的平均辐射温度。以黑河流域进行的星—机—地遥感综合观测试验加密观测——盈科绿洲玉米地的热像仪和手持式红外辐射计温度测量数据为基础对不同采样方式获得的地面辐射温度进行对比。对于热像仪数据:①采用阈值法对热像仪影像中的玉米和土壤背景两组分进行分离,获得了各自辐射温度的平均值;②利用LAB彩色变换法处理同步拍摄的真彩色照片,获得每块玉米样地的植被覆盖度;③最终结合组分温度和植被覆盖度求得地块平均的辐射温度。经过实验对比发现,由热红外图像计算获得的地面平均辐射温度与手持式红外辐射计垂直垄或顺垄条带采样获得的地面平均辐射温度差值较小,基本在±1℃以内,而3种测量方式的最大值、最小值相差较多。还模拟了几种常见尺度下利用手持式红外辐射计进行随机采样时,其采样平均值以不同的置信度处于真实温度±0.5℃之间所对应的采样次数。分析表明,基于点测量的采样方案难以仅利用1~2台手持式红外辐射计实现对田块或更大尺度平均辐射温度的准确测量,高时空采样频率是保障地面辐射温度测量精度的前提,与遥感像元尺度相匹配的地面真实性检验需要进行测量方法和设备的革新。

关键词:  田块尺度辐射温度热像仪手持式辐射计采样方式    
Abstract:

Thermal camera,widely used in situ measurement of land surface temperature(LST), has an advantage of obtaining component brightness temperature. A simultaneous airborne, satellite-borne, and ground-based remote sensing field campaign was carried out in the Heihe River Basin of northwest China from May to July, 2008. The radiative temperatures were obtained by two portable infrared radiometers and one thermal camera at the maize field patches around the weather station in Yingke Oasis Area with three different sampling schemes. Average temperatures of the field patches were extracted with those data. The thermal camera′s data was processed as: Firstly, maize and the soil were separated by statistical threshold of radiative temperatures in thermal images, and then their mean radiative temperatures were calculated, respectively. Secondly, with the LAB color space transform technique, the vegetation fraction of each field patch is estimated from visible photos taken simultaneously. Finally, each patch′s mean radiative temperature was obtained by the sum of the component temperatures of maize and soil  weighted by vegetation fraction cover. By comparing of the mean radiative temperatures obtained by the thermal camera and portable radiometers sampling in cross-row and along-row direction, we found that their differences are small, and between -1 and +1 . But, both maximum and minimum temperatures of the three methods differ a lot. By simulation on different reliability levels, we also obtained the numbers of randomly sampled points on different pixel scales. Our result indicates that it is difficult to obtain an accurate mean brightness temperature of filed patch with just only 1-2 portable radiometers based on the general point-based measure scheme. To get more accurate data for the validation of LST retrieved in different remote sensing pixel scales, new methods and instruments with high temporal and spatial sampling frequencies are required. 

Key words: Field patch scale    Radiative temperatures    Thermal camera    Portable radiometer    Sampling method
收稿日期: 2009-02-04 出版日期: 2009-07-10
:  P423.3  
基金资助:

国家自然科学基金项目“复杂地形区热红外方向性辐射建模及组分温度反演”(编号:40871164);国家重点基础研究发展计划项目“地表时空变化特征参数的遥感定量描述与尺度转换”(编号:2007CB714402);中国科学院西部行动计划(二期)项目“黑河流域遥感—地面观测同步试验与综合模拟平台建设”(编号:KZCX2-XB2-09)资助.

通讯作者: 阎广建(1972-), 男,山西应县人,教授,主要从事多角度遥感、热红外遥感建模及反演以及尺度转换等方面研究.     E-mail: gjyan@bnu.edu.cn
作者简介: 康国婷(1984-),女,吉林吉林市人,硕士研究生,主要从事热红外高光谱遥感反演地表温度研究. E-mail:ting_92@163.com
服务  
把本文推荐给朋友
加入引用管理器
E-mail Alert
RSS
作者相关文章  
阎广建
任华忠
王颢星
钱永刚
康国婷

引用本文:

康国婷,阎广建,任华忠,王颢星,钱永刚. 田块尺度作物辐射温度获取方法对比研究[J]. 地球科学进展, 2009, 24(7): 784-792.

Kang Guoting, Yan Guangjian, Ren Huazhong, Wang Haoxing, Qian Yonggang. A Comparison of Different Ground-based Radiative Temperature Measurement Methods on the Field Patch Scale. Advances in Earth Science, 2009, 24(7): 784-792.

链接本文:

http://www.adearth.ac.cn/CN/10.11867/j.issn.1001-8166.2009.07.0784        http://www.adearth.ac.cn/CN/Y2009/V24/I7/784

[1] Zhu Huaisong, Liu Xiaomeng, Pei Huan. Summary on retrieval of land surface temperature using thermal infrared remote sensing[J].Arid Meteorology, 2007,25(2):17-21.[朱怀松, 刘晓锰, 裴欢. 热红外遥感反演地表温度研究现状[J].干旱气象, 2007,25(2):17-21.]
[2] Zhang Renhua.Experimental Remote Sensing Model and Its Land Surface Process[M]. Beijing: Science Press,1996.[张仁华. 实验遥感模型及地面基础[M]. 北京:科学出版社,1996.]
[3] Wan Z M, Dozier J. A generalized split-window algorithm for retrieving land surface temperature from space[J].IEEE Transactions on Geoscience and Remote Sensing,1996, 34(4): 892-905.
[4] Xu Xiru, Liu Qinhuo, Chen Jiayi. The remote sensing of land surface temperature[J].Acta Scientiarum Naturalium Universitatis Pekinensis,1998,34(2):248-253.[徐希孺,柳钦火,陈家宜. 遥感陆面温度[J]. 北京大学学报,1998,34(2):248-253.]
[5] Yu Shanshan, Yu Tao, Gu Xingfa, et al. Investigating the gap frequency of a maize canopy using night TIR fata[J].Journal of Remote Sensing,2006,10(5):683-689.[余珊珊,余涛,顾行发,等.利用夜间热红外数据求取玉米冠层孔隙率[J].遥感学报, 2006,10(5):683-689.]
[6] Francois C, Ottlé C, Prévot L. Analytical parameterization of canopy directional emissivity and directional radiance in the thermal infrared. Application on the retrieval of soil and foliage temperature using two directional measurements[J].International Journal of Remote Sensing,1997,18(12):2 587-2 621.
[7] Purevdorj T, Tateishi R, Ishiyama T,et al.Relationships between percent vegetation cover and vegetation indices[J].International Journal of Remote Sensing,1998, 19(18): 3 5193 535.[ZK)]
[8] Gitelson A A, Kaufman Y J, Stark R,et al.Novel algorithms for remote estimation of vegetation fraction[J]. Remote Sensing of Environment,2002, 80(1): 76-87.
[9] Zhang Wenbo,Fu Suhua, Liu Baoyuan. Error assessment of visual estimation plant coverage[J].Journal of Beijing Normal University (Natural Science), 2001, 37(3): 402-408.[章文波, 符素华, 刘宝元.目估法测量植被盖度的精度分析[J].北京师范大学学报:自然科学版, 2001, 37(3): 402-408.]
[10] Zhang Yunxia,Li Xiaobing, Chen Yunhao. Overview of field and multi-scale remote sensing measurement approaches to grassland vegetation coverage[J].Advances in Earth Science,2003,18(1): 85-93.[张云霞, 李晓兵, 陈云浩.草地植被覆盖度的多尺度遥感与实地测量方法综述[J].地球科学进展, 2003, 18(1): 85-93.]

[1] 黄妙芬;刘绍民;刘素红;朱启疆. 地表温度和地表辐射温度差值分析[J]. 地球科学进展, 2005, 20(10): 1075-1082.