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Global Land Cover Heterogeneity Characteristics at Moderate Resolution for Mixed Pixel Modeling and Inversion

Wentao Yu, Jing Li, Qinhuo Liu, Yelu Zeng, Jing Zhao, Baodong Xu, Gaofei Yin
2018 Remote Sensing  
Because of a lack of understanding of the heterogeneous characteristics of global mixed pixels, few studies have focused on modeling and inversion algorithms in heterogeneous areas.  ...  Global heterogeneity features at the 1-km scale are extracted from the 'GlobeLand30' land cover dataset with a spatial resolution of 30 m.  ...  This scheme provides an approach to evaluate the heterogeneity characteristics of global mixed pixels and analyze the influence of land cover heterogeneity on mixed pixel modeling.  ... 
doi:10.3390/rs10060856 fatcat:dwx5hnmvm5d6lasrrrvyqvlbdq

A global analysis of urban reflectance

C. Small
2005 International Journal of Remote Sensing  
The 10 to 20 m scale of urban land cover elements results in a preponderance of spectrally mixed pixels when imaged with moderate resolution optical sensors like Landsat.  ...  At scales of 10 to 30 meters, urban areas are considerably more heterogeneous than other land cover types investigated.  ...  used to distinguish urban land cover in moderate resolution optical imagery.  ... 
doi:10.1080/01431160310001654950 fatcat:5lxxipsxpvgntgiqskyef7hllm

A proposed extension to the soil moisture and ocean salinity level 2 algorithm for mixed forest and moderate vegetation pixels

Rocco Panciera, Jeffrey P. Walker, Jetse Kalma, Edward Kim
2011 Remote Sensing of Environment  
This retrieval approach is tested in this study using airborne L-band data over an area the size of a SMOS pixel characterised by a mix Eucalypt forest and moderate vegetation types (grassland and crops  ...  The current baseline soil moisture retrieval algorithm adopted by SMOS and implemented in the SMOS Level 2 (SMOS L2) processor partially accounts for the sub-pixel heterogeneity of the land surface, by  ...  The authors wish to thank Phillip Maisongrande and Gilles Boulet at the Centre d'Etudes Spatiales de la BIOsphere (CESBIO) for the supervised classification of the Landsat 5 Thematic Mapper scene, and  ... 
doi:10.1016/j.rse.2011.07.017 fatcat:lb5qdrerljfb3fcxbbprufhf6a

Generating High Resolution LAI Based on a Modified FSDAF Model

Huan Zhai, Fang Huang, Hang Qi
2020 Remote Sensing  
Compared to the simulation results of FSDAF, the modified FSDAF model showed higher accuracy and reflected more spatial details in the boundary areas of different land cover types.  ...  We proposed a new model to generate high resolution LAI, by combining linear pixel unmixing and the Flexible Spatiotemporal Data Fusion (FSDAF) method.  ...  Acknowledgments: The authors would like to thank the reviewers and editors for their valuable comments and suggestions. Conflicts of Interest: The authors declare no conflict of interest.  ... 
doi:10.3390/rs12010150 fatcat:ngbu4pmk2rhp7jbainsstpnvgu

Estimating the Maximal Light Use Efficiency for Different Vegetation through the CASA Model Combined with Time-Series Remote Sensing Data and Ground Measurements

Ainong Li, Jinhu Bian, Guangbin Lei, Chengquan Huang
2012 Remote Sensing  
Based on an existing land cover map and MODIS NDVI product, the linear unmixing method with a moving window was adopted to estimate the time-series NDVI for different end members in a MODIS NDVI pixel;  ...  These are 0.669 gC·MJ −1 , 0.450 gC·MJ −1 and 0.126 gC·MJ −1 for the xerophilous grasslands with high, moderate and low vegetation fraction respectively, 0.192 gC·MJ −1 for the hygrophilous grasslands,  ...  Acknowledgements We are grateful to the anonymous referees for their valuable comments and suggestions. We also wish to express our gratitude to all the contractors and image providers.  ... 
doi:10.3390/rs4123857 fatcat:z3u5nukzwzfgdpty5fiqioccry

Estimating vegetation structural effects on carbon uptake using satellite data fusion and inverse modeling

Gregory P. Asner, C. Ann Bateson, Jeffrey L. Privette, Nazmi El Saleous, Carol A. Wessman
1998 Journal of Geophysical Research  
their structural characteristics for regional-scale biogeochemical research.  ...  We developed and tested a satellite data fusion and radiative transfer inverse modeling approach to deliver estimates of vegetation structure in a savanna region of Texas.  ...  We thank Jim Ansley and Steve  ... 
doi:10.1029/98jd02459 fatcat:istdsjkbxzcmhplbqklslp4jmm

Spatially and temporally continuous LAI datasets based on the mixed pixel decomposition method

Jianjun Zhao, Yanying Wang, Hongyan Zhang, Zhengxiang Zhang, Xiaoyi Guo, Shan Yu, Wala Du
2016 SpringerPlus  
The LAI features are not discernible when a global LAI product is implemented at the regional scale because it has low resolution and different land cover types.  ...  A global LAI has been routinely produced by the Moderate Resolution Imaging Spectro-radiometer (MODIS) and Advanced Very High Resolution Radiometer (AVHRR).  ...  Acknowledgements The authors would like to thank the entire GIMMS group for permitting the usage of the NDVI dataset.  ... 
doi:10.1186/s40064-016-2166-9 pmid:27186480 pmcid:PMC4844580 fatcat:nm6hl3q2m5elphzrfsdy2bhhhu

Variability in surface BRDF at different spatial scales (30m–500m) over a mixed agricultural landscape as retrieved from airborne and satellite spectral measurements

Miguel O. Román, Charles K. Gatebe, Crystal B. Schaaf, Rajesh Poudyal, Zhuosen Wang, Michael D. King
2011 Remote Sensing of Environment  
when sub-pixel differences in the BRDF are aggregated to a moderate resolution 21 satellite pixel.  ...  Over the past decade, the role of multiangle remote sensing has been central to the 1 development of algorithms for the retrieval of global land surface properties including models of 2 the bidirectional  ...  This layer provides basic QA for BRDF model inver-363 sion data, with green pixels denoting high-quality full inversion retrievals, red pixels denoting 364 moderate quality magnitude inversion retrievals  ... 
doi:10.1016/j.rse.2011.04.012 fatcat:ajwharlibzhldjsttazmoy4dmy

Identification of the Characteristic Scale of Fine Ground Objects: A Case Study of the Core Observation Area in the Middle Reaches of the Heihe River Basin

Xiuyi Wu, Wenping Yu, Jinan Shi, Mingguo Ma, Xiaolu Li, Wenjian Wu
2021 Remote Sensing  
Capturing the spatial heterogeneity and characteristic scale is the key to determining the spatial patterns of land surfaces.  ...  experiments on moderate- and high-resolution remotely sensed ASTER and CASI NDVI images.  ...  Acknowledgments: The authors would thank all the institutes and universities involved in the observation experiment for their sharing the data.  ... 
doi:10.3390/rs13030362 fatcat:jpetcvmojvg7lixs54ta6akwmy

Generating global Leaf Area Index from Landsat: Algorithm formulation and demonstration

Sangram Ganguly, Ramakrishna R. Nemani, Gong Zhang, Hirofumi Hashimoto, Cristina Milesi, Andrew Michaelis, Weile Wang, Petr Votava, Arindam Samanta, Forrest Melton, Jennifer L. Dungan, Eric Vermote (+3 others)
2012 Remote Sensing of Environment  
delineating pure vegetated components as opposed to mixed pixels.  ...  reflectances; 2) the proximity of Landsatobserved surface reflectance and corresponding reflectances as characterized by the model simulation; and 3) the quality of the input land cover type in accurately  ...  Acknowledgments We acknowledge funding from Earth Science and Advanced Information Systems Technology programs at NASA.  ... 
doi:10.1016/j.rse.2011.10.032 fatcat:t6smyjxtxfdgxkuiouty2hgj7m

Spectral unmixing based spatiotemporal downscaling fusion approach

Wenjie Liu, Yongnian Zeng, Songnian Li, Wei Huang
2020 International Journal of Applied Earth Observation and Geoinformation  
In this paper, we propose a Linear Spectral Unmixing-based Spatiotemporal Data Fusion Model (LSUSDFM) for spatial and temporal data fusion.  ...  In this model, the endmember abundance of the low-resolution image pixel is calculated based on that of the highresolution image by the spectral mixture analysis.  ...  However, land cover classification assigns each image pixel with a certain land cover class, which ignores the mixed pixels existed in remote sensing images (Keshava and Mustard, 2002) .  ... 
doi:10.1016/j.jag.2020.102054 fatcat:ftfkbcbze5b25hct6fpjzwqk64

Radiative transfer based scaling of LAI retrievals from reflectance data of different resolutions

Yuhong Tian, Yujie Wang, Yu Zhang, Yuri Knyazikhin, Jan Bogaert, Ranga B Myneni
2003 Remote Sensing of Environment  
It is shown that LAI retrieval errors at coarse resolution are inversely related to the proportion of the dominant land cover in such pixel.  ...  The increasing probability of land cover mixtures with decreasing resolution is defined as heterogeneity, which is a key concept in scaling studies.  ...  Jan Bogaert is a Postdoctoral Fellow of the Fund for Scientific Research-Flanders. We thank R. Fernandes for stimulating discussions.  ... 
doi:10.1016/s0034-4257(02)00102-5 fatcat:lwnxrfkuqbf7na5drlhuzza6cm

Comparison and assessment of coarse resolution land cover maps for Northern Eurasia

Dirk Pflugmacher, Olga N. Krankina, Warren B. Cohen, Mark A. Friedl, Damien Sulla-Menashe, Robert E. Kennedy, Peder Nelson, Tatiana V. Loboda, Tobias Kuemmerle, Egor Dyukarev, Vladimir Elsakov, Viacheslav I. Kharuk
2011 Remote Sensing of Environment  
Information on land cover at global and continental scales is critical for addressing a range of ecological, socioeconomic and policy questions.  ...  Total pixellevel agreement between global maps and six test sites was moderate to fair (overall agreement: 0.67-0.74, Kappa: 0.41-0.52) and increased by 0.09-0.45 when only homogenous land cover types  ...  Network for Global Change Research and the Alexander von Humboldt Foundation.  ... 
doi:10.1016/j.rse.2011.08.016 fatcat:akya4yskxvgcrl7xsbcyngagem

Northern Peatland Vegetation and the Carbon Cycle: A Remote Sensing Approach [chapter]

A. Harris, R. G. Bryant
2013 Carbon Cycling in Northern Peatlands  
and (iv) continued development of radiative transfer models that can be applied to heterogeneous peatland plant assemblages.  ...  Whilst in situ observations can provide detailed information for a given location, remote sensing is the only viable means of collecting land-surface data in a spatially continuous manner across a range  ...  Acknowledgements The reviewers are thanked for their help in improving an earlier version of this manuscript.  ... 
doi:10.1029/2008gm000818 fatcat:yfv7vbnqtzcerkvyuomtu7mnxe

Evaluating the performance of the MODIS Leaf Area Index (LAI) product over a Mediterranean dryland planted forest

M. Sprintsin, A. Karnieli, P. Berliner, E. Rotenberg, D. Yakir, S. Cohen
2009 International Journal of Remote Sensing  
However, for heterogeneous and sparse planted forests that are common to the semi-arid eastern Mediterranean region, the data at low spatial resolution may be significantly biased by the contribution of  ...  The relationship between MOD12C1 Land Cover Type 3 and MOD15A2 products is discussed.  ...  Currently, LAI is globally and routinely provided by NASA as an operational Moderate Resolution Imaging Spectroradiometer (MODIS) product at 1-km spatial resolution and at 8-day intervals.  ... 
doi:10.1080/01431160903032885 fatcat:mtyxb5a42faf7fwpb7bdelzwki
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