地面激光雷达的单木真实叶面积指数提取
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摘要
针对已有的测量叶面积指数(LAI)的方法中,LAI测量结果受其定义、采样方法、数据分析和仪器误差等影响产生极大差异的问题,该文使用地面激光雷达(TLS)提取LAI,对北京林业大学校园内具有代表性的单株树木进行了扫描,通过对数据预处理提取出树冠点云,将其模拟为半球图像后运用球极平面投影和Lambert方位角等面积投影两种投影方法,通过统计面积的方法分别计算不同投影方法和图像划分方法下的孔隙率,进而计算出真实叶面积指数。同时与利用叶面积指数仪LAI-2000所测得的数据进行对比。研究结果表明,地面激光雷达提取单木真实叶面积指数与实测值对比,两种投影下18个环的图像划分方法均更接近真实值,其中在Lambert方位角等面积投影下计算结果更准确。
Aiming at the problem that traditional methods for leaf area index(LAI)measuring have greatly different results by its definition,sampling method,data analysis and instrument error,LAI was extracted by terrestrial laser scanner(TLS)in this study.Some typical trees were scanned in Beijing Forestry University,the point cloud data was spliced and useless points were removed to get crown point cloud data.And it was turn into hemisphere image.The hemisphere image was projected on a plane by stereographic projection and Lambert equal area azimuth projection,and then real LAI was got.At the same time the results were compared with measured data by using LAI-2000.The result showed that under two kinds of projection,LAI was more approached the truly value when the image was divided into 18 rings,especially under Lambert equal area azimuth projection.
Aiming at the problem that traditional methods for leaf area index(LAI)measuring have greatly different results by its definition,sampling method,data analysis and instrument error,LAI was extracted by terrestrial laser scanner(TLS)in this study.Some typical trees were scanned in Beijing Forestry University,the point cloud data was spliced and useless points were removed to get crown point cloud data.And it was turn into hemisphere image.The hemisphere image was projected on a plane by stereographic projection and Lambert equal area azimuth projection,and then real LAI was got.At the same time the results were compared with measured data by using LAI-2000.The result showed that under two kinds of projection,LAI was more approached the truly value when the image was divided into 18 rings,especially under Lambert equal area azimuth projection.
引文
[1]CHEN J M,CHEN X Y,JU W M,et al.Distributed hydrological model for mapping evapotranspiration using remote sensing inputs[J].Journal of Hydrology,2005,305(1/4):15-39.
[2]NIKOLOV N T,FOX D G.A coupled carbon-waterenergy-vegetation model to assess responses of temperate forest ecosystems to changes in climate and atmospheric CO2.Part 1.Model concept[J].Environmental Pollution,1994,83(1/2):251-262.
[3]徐光彩.小光斑波形激光雷达森林LAI和单木生物量估测研究[D].北京:中国林业科学研究院,2013.(XUGuangcai.Forest LAI and individual trees biomass estimation using small-footprint full-waveform LiDARdata[D].Beijing:China Academy of Forestry,2013.)
[4]CLEUGH H A,LEUNING R,MU Q Z,et al.Regional evaporation estimates from flux tower and MODIS satellite data[J].Remote Sensing of Environment,2007,106(3):285-304.
[5]JONGSCHAAP R E E.Run-time calibration of simulation models by integrating remote sensing estimates of leaf area index and canopy nitrogen[J].European Journal of Agronomy,2006,24(4):316-324.
[6]CHEN J M,RICH P M,GOWER S T,et al.Leaf area index of boreal forests:theory,techniques,and measurements[J].Journal of Geophysical Research(Atmospheres),1997,102(D24):29429-29443.
[7]吴伟斌,洪添胜,王锡平,等.叶面积指数地面测量方法的研究进展[J].华中农业大学学报,2007,26(2):270-275.(WU Weibin,HONG Tiansheng,WANG Xiping,et al.Advance in ground-based LAI measurement methods[J].Journal of Huazhong Agricultural University,2007,26(2):270-275.)
[8]HOSOI F,OMASA K.Voxel-based 3-D modeling of individual trees for estimating leaf area density using high-resolution portable scanning lidar[J].IEEETransactions on Geoscience and Remote Sensing,2006,44(12):3610-3618.
[9]ZANDE D V D,JONCKHEERE I,STUCKENS J,et al.Sampling design of ground-based lidar measurements of forest canopy structure and its effect on shadowing[J].Canadian Journal of Remote Sensing,2008,34(6):526-538.
[10]TAKEDA T,OGUMA H,SANO T,et al.Estimating the plant area density of a Japanese larch(Larix kaempferi Sarg.)plantation using aground-based laser scanner[J].Agricultural and Forest Meteorology,2008,148(3):428-438.
[11]TAKEDA T,OGUMA H,YONE Y,et al.Comparison of leaf area density measured by laser range finder and stratified clipping method[J].Phyton(Annales Rei Botanicae),2005,45(4):505-510.
[12]SUMIDA A,NAKAI T,YAMADA M,et al.Groundbased estimation of leaf area index and vertical distribution of leaf area density in a Betula ermanii forest[J].Silva Fennica,2009,43(5):799-816.
[13]HUANG P,PRETZSCH H.Using terrestrial laser scanner for estimating leaf areas of individual trees in a conifer forest[J].Trees,2010,24(4):609-619.
[14]ZANDE D V D,STUCKENS J,VERSTRAETEN WW,et al.3Dmodeling of light interception in heterogeneous forest canopies using ground-based LiDAR data[J].International Journal of Applied Earth Observation and Geoinformation,2011,13(5):792-800.
[15]BLAND M,WIDLOWSKI J L,FOURNIER R A,et al.Estimating leaf area distribution in savanna trees from terrestrial LiDAR measurements[J].Agricultural and Forest Meteorology,2011,151(9):1252-1266.
[16]SANZ R,ROSELL J R,LLORENS J,et al.Relationship between tree row LIDAR-volume and leaf area density for fruit orchards and vineyards obtained with a LIDAR 3Ddynamic measurement system[J].Agricultural and Forest Meteorology,2013,171-172:153-162.
[17]BLAND M,BALDOCCHI D D,WIDLOWSKI J L,et al.On seeing the wood from the leaves and the role of voxel size in determining leaf area distribution of forests with terrestrial LiDAR[J].Agricultural and Forest Meteorology,2014,184:82-97.
[18]尹华丽,王佳,冯仲科,等.林分参数提取及与大气颗粒物分布关系[J].福建农林大学学报(自然科学版),2017,46(3):270-276.(YIN Huali,WANG Jia,FENGZhongke,et al.Extraction of forest stand spatial structure and its relationship with atmospheric particulate matter distribution[J].Journal of Fujian Agricultural and Forestry University(Natural Science Edition),2017,46(3):270-276.)
[19]DANSON F M,HETHERINGTON D,MORSDORFF,et al.Forest canopy gap fraction from terrestrial laser scanning[J].IEEE Geoscience and Remote Sensing Letters,2007,4(1):157-160.
[20]高纪青,云挺,薛联凤.基于鱼目摄像和地面激光雷达的真实叶面积指数计算[J].南京师大学报(自然科学版),2014,37(4):137-144.(GAO Jiqing,YUN Ting,XUE Lianfeng.The calculation of actual LAI based on terrestrial laser scanning data and fish eye camera[J].Journal of Nanjing Normal Univeristy(Natural Science Edition),2014,37(4):137-144.)
[21]李明,张长利,房俊龙.基于图像处理技术的小麦叶面积指数的提取[J].农业工程学报,2010,26(1):205-209.(LI Ming,ZHANG Changli,FANG Junlong.Extraction of leaf area index of wheat based on image processing technique[J].Transactions of the CSAE,2010,26(1):205-209.)
[22]ZHENG Guang,MONIKA M L,SOO-HYUNG K.Retrieval of effective leaf area index in heterogeneous forests with terrestrial laser scanning[J].IEEE Transactions on Geoscience and Remote Sensing,2013,51(2):777-786.
[23]WELLES J M.Some indirect methods of estimating canopystructure[J].Remote Sensing Reviews,1990,5(1):31-43.
[24]张仁华,孙晓敏,朱治林.叶面积指数的快速测定方法:植被定量遥感的地面标定技术[J].国土资源遥感,1998(35):54-60.(ZHANG Renhua,SUN Xiaomin,ZHU Zhilin.A speedier measuring technology for leaf area index:a calibration tool in quantitative remote sensing of vegetation[J].Remote Sensing for Land&Resources,1998(35):54-60.)
[25]潘桂颖.基于半球摄影法的水稻冠层结构参数测量与反演[D].杭州:浙江大学,2011.(PAN Guiying.Measurement and extracting rice canopy structure parameters based on hemisphere photography[D].Hangzhou:University of Zhejiang,2011.)
[2]NIKOLOV N T,FOX D G.A coupled carbon-waterenergy-vegetation model to assess responses of temperate forest ecosystems to changes in climate and atmospheric CO2.Part 1.Model concept[J].Environmental Pollution,1994,83(1/2):251-262.
[3]徐光彩.小光斑波形激光雷达森林LAI和单木生物量估测研究[D].北京:中国林业科学研究院,2013.(XUGuangcai.Forest LAI and individual trees biomass estimation using small-footprint full-waveform LiDARdata[D].Beijing:China Academy of Forestry,2013.)
[4]CLEUGH H A,LEUNING R,MU Q Z,et al.Regional evaporation estimates from flux tower and MODIS satellite data[J].Remote Sensing of Environment,2007,106(3):285-304.
[5]JONGSCHAAP R E E.Run-time calibration of simulation models by integrating remote sensing estimates of leaf area index and canopy nitrogen[J].European Journal of Agronomy,2006,24(4):316-324.
[6]CHEN J M,RICH P M,GOWER S T,et al.Leaf area index of boreal forests:theory,techniques,and measurements[J].Journal of Geophysical Research(Atmospheres),1997,102(D24):29429-29443.
[7]吴伟斌,洪添胜,王锡平,等.叶面积指数地面测量方法的研究进展[J].华中农业大学学报,2007,26(2):270-275.(WU Weibin,HONG Tiansheng,WANG Xiping,et al.Advance in ground-based LAI measurement methods[J].Journal of Huazhong Agricultural University,2007,26(2):270-275.)
[8]HOSOI F,OMASA K.Voxel-based 3-D modeling of individual trees for estimating leaf area density using high-resolution portable scanning lidar[J].IEEETransactions on Geoscience and Remote Sensing,2006,44(12):3610-3618.
[9]ZANDE D V D,JONCKHEERE I,STUCKENS J,et al.Sampling design of ground-based lidar measurements of forest canopy structure and its effect on shadowing[J].Canadian Journal of Remote Sensing,2008,34(6):526-538.
[10]TAKEDA T,OGUMA H,SANO T,et al.Estimating the plant area density of a Japanese larch(Larix kaempferi Sarg.)plantation using aground-based laser scanner[J].Agricultural and Forest Meteorology,2008,148(3):428-438.
[11]TAKEDA T,OGUMA H,YONE Y,et al.Comparison of leaf area density measured by laser range finder and stratified clipping method[J].Phyton(Annales Rei Botanicae),2005,45(4):505-510.
[12]SUMIDA A,NAKAI T,YAMADA M,et al.Groundbased estimation of leaf area index and vertical distribution of leaf area density in a Betula ermanii forest[J].Silva Fennica,2009,43(5):799-816.
[13]HUANG P,PRETZSCH H.Using terrestrial laser scanner for estimating leaf areas of individual trees in a conifer forest[J].Trees,2010,24(4):609-619.
[14]ZANDE D V D,STUCKENS J,VERSTRAETEN WW,et al.3Dmodeling of light interception in heterogeneous forest canopies using ground-based LiDAR data[J].International Journal of Applied Earth Observation and Geoinformation,2011,13(5):792-800.
[15]BLAND M,WIDLOWSKI J L,FOURNIER R A,et al.Estimating leaf area distribution in savanna trees from terrestrial LiDAR measurements[J].Agricultural and Forest Meteorology,2011,151(9):1252-1266.
[16]SANZ R,ROSELL J R,LLORENS J,et al.Relationship between tree row LIDAR-volume and leaf area density for fruit orchards and vineyards obtained with a LIDAR 3Ddynamic measurement system[J].Agricultural and Forest Meteorology,2013,171-172:153-162.
[17]BLAND M,BALDOCCHI D D,WIDLOWSKI J L,et al.On seeing the wood from the leaves and the role of voxel size in determining leaf area distribution of forests with terrestrial LiDAR[J].Agricultural and Forest Meteorology,2014,184:82-97.
[18]尹华丽,王佳,冯仲科,等.林分参数提取及与大气颗粒物分布关系[J].福建农林大学学报(自然科学版),2017,46(3):270-276.(YIN Huali,WANG Jia,FENGZhongke,et al.Extraction of forest stand spatial structure and its relationship with atmospheric particulate matter distribution[J].Journal of Fujian Agricultural and Forestry University(Natural Science Edition),2017,46(3):270-276.)
[19]DANSON F M,HETHERINGTON D,MORSDORFF,et al.Forest canopy gap fraction from terrestrial laser scanning[J].IEEE Geoscience and Remote Sensing Letters,2007,4(1):157-160.
[20]高纪青,云挺,薛联凤.基于鱼目摄像和地面激光雷达的真实叶面积指数计算[J].南京师大学报(自然科学版),2014,37(4):137-144.(GAO Jiqing,YUN Ting,XUE Lianfeng.The calculation of actual LAI based on terrestrial laser scanning data and fish eye camera[J].Journal of Nanjing Normal Univeristy(Natural Science Edition),2014,37(4):137-144.)
[21]李明,张长利,房俊龙.基于图像处理技术的小麦叶面积指数的提取[J].农业工程学报,2010,26(1):205-209.(LI Ming,ZHANG Changli,FANG Junlong.Extraction of leaf area index of wheat based on image processing technique[J].Transactions of the CSAE,2010,26(1):205-209.)
[22]ZHENG Guang,MONIKA M L,SOO-HYUNG K.Retrieval of effective leaf area index in heterogeneous forests with terrestrial laser scanning[J].IEEE Transactions on Geoscience and Remote Sensing,2013,51(2):777-786.
[23]WELLES J M.Some indirect methods of estimating canopystructure[J].Remote Sensing Reviews,1990,5(1):31-43.
[24]张仁华,孙晓敏,朱治林.叶面积指数的快速测定方法:植被定量遥感的地面标定技术[J].国土资源遥感,1998(35):54-60.(ZHANG Renhua,SUN Xiaomin,ZHU Zhilin.A speedier measuring technology for leaf area index:a calibration tool in quantitative remote sensing of vegetation[J].Remote Sensing for Land&Resources,1998(35):54-60.)
[25]潘桂颖.基于半球摄影法的水稻冠层结构参数测量与反演[D].杭州:浙江大学,2011.(PAN Guiying.Measurement and extracting rice canopy structure parameters based on hemisphere photography[D].Hangzhou:University of Zhejiang,2011.)