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Separating overstory and understory leaf area indices for global needleleaf and deciduous broadleaf forests by fusion of MODIS and MISR data

Yang Liu, Ronggao Liu, Jan Pisek, Jing M. Chen
2017 Biogeosciences  
Spatially and seasonally variable forest understory reflectivity helps to account for the effects of the forest background on LAI retrieval while compared with constant forest background.  ...  Significant seasonal variations occur for understory vegetation in these zones with LAI values up to 2–3 from June to August.  ...  The MODIS data were downloaded from the Land Processes Distributed Active Archive Center.  ... 
doi:10.5194/bg-14-1093-2017 fatcat:xu6777gv4rf7jo7zf23yexhuom

Separating of Overstory and Understory Leaf Area Indices for Global Needleleaf and Deciduous Broadleaf Forests by Fusion of MODIS and MISR Data

Yang Liu, Ronggao Liu, Jan Pisek, Jing Chen
2016 Biogeosciences Discussions  
Spatially and seasonally variable forest understory reflectivity helps to account for the effects of the forest background on LAI retrieval while compared with constant forest background.  ...  ) due to the more clumped foliage and easier penetration of light to the forest floor in needleleaf forests.  ...  The forest overstory LAI was derived from the MODIS land surface reflectance data with the effects from the background corrected based on the MISR monthly forest background reflectivity.  ... 
doi:10.5194/bg-2016-448 fatcat:si3emjvv5baqrjyvv2y2imvv3m

Strong cooling induced by stand-replacing fires through albedo in Siberian larch forests

Dong Chen, Tatiana V. Loboda, Tao He, Yi Zhang, Shunlin Liang
2018 Scientific Reports  
The net albedo-induced forcing of the Siberian larch forests in the future would hinge on the interaction between the fire-induced cooling effect and the climate-induced warming effect, both of which will  ...  The Siberian larch forests, taking up about a fifth of the global boreal biome, are different from the North American boreal forests in that they generally do not undergo a secondary succession.  ...  Dongdong Wang at the Department of Geographical Sciences, University of Maryland, Dr. Zhanqing Li at the Department of Atmospheric and Oceanic Science, University of Maryland, and Dr.  ... 
doi:10.1038/s41598-018-23253-1 pmid:29555985 pmcid:PMC5859174 fatcat:ewmrkzc6e5hu3hoivnz37dzryy

Seasonal Reflectance Courses of Forests [chapter]

Tiit Nilson, Miina Rautiainen, Jan Pisek, Urmas Peterso
2012 New Advances and Contributions to Forestry Research  
Based on empirical reflectance data and radiative transfer modelling, Kobayashi et al. (2007) reported that seasonal changes in a larch forest understory (or forest floor) influence both the absolute  ...  Hence, the concept of "land surface phenology" (Friedl et al., 2006) is often used to describe the seasonal pattern of variation in vegetated land surfaces observed from remote sensing.  ...  .), ISBN: 978-953-51-0529-9, InTech, Available from:  ... 
doi:10.5772/34962 fatcat:afesg5mniraorbp27j6wlqhsnu

Spectral Properties of Coniferous Forests: A Review of In Situ and Laboratory Measurements

Miina Rautiainen, Petr Lukeš, Lucie Homolová, Aarne Hovi, Jan Pisek, Matti Mõttus
2018 Remote Sensing  
We look at the spatial, directional, and seasonal variations in needle, shoot, woody element, and understory spectra in coniferous forests, based on measurements.  ...  Finally, we provide a synthesis of gaps in the current knowledge on spectra of elements forming coniferous forests that could also serve as a recommendation for planning scientific efforts in the future  ...  derived from the reflectance spectra [33] .  ... 
doi:10.3390/rs10020207 fatcat:mv2tbctdbzhi3l43zutumrin3u

Review: advances in in situ and satellite phenological observations in Japan

Shin Nagai, Kenlo Nishida Nasahara, Tomoharu Inoue, Taku M. Saitoh, Rikie Suzuki
2015 International journal of biometeorology  
The relationships between seasonal variations in RGB-derived indices or spectral characteristics and the ecological and CO 2 flux measurement data have been well validated.  ...  Differences in phenology among ecosystems and tree species have been detected by analyzing the seasonal variation of red, green, and blue digital numbers (RGB values) extracted from phenological images  ...  This study was supported by the Environment Research and Technology Development Fund (S-9) of the Ministry of the Environment of Japan.  ... 
doi:10.1007/s00484-015-1053-3 pmid:26307639 pmcid:PMC4821867 fatcat:t4lzwur4hfccfb45n6nnaw4cgu

Effect of forest canopy structure on wintertime Land Surface Albedo: Evaluating CLM5 simulations with in‐situ measurements

Johanna Malle, Nick Rutter, Clare Webster, Giulia Mazzotti, Leanne Wake, Tobias Jonas
2021 Journal of Geophysical Research - Atmospheres  
Eric Sproles and one anonymous reviewer for their insightful comments and suggestions which helped improve the quality of the manuscript.  ...  The authors further acknowledge the support of the SLF electronics and mechanics workshop in assembling and maintaining the deployed instrumentation. Finally, we thank Dr.  ...  of the forest floor at all.  ... 
doi:10.1029/2020jd034118 fatcat:ouqb2gzd5bex7kc6qk76ivtsae

The influence of burn severity on postfire vegetation recovery and albedo change during early succession in North American boreal forests

Yufang Jin, James T. Randerson, Scott J. Goetz, Pieter S. A. Beck, Michael M. Loranty, Michael L. Goulden
2012 Journal of Geophysical Research  
the effects of fire on surface albedo.  ...  MODIS Enhanced Vegetation Index and Albedo [12] Vegetation indices (VI) from satellite observed surface reflectance at two or more spectral bands highlight the presence and abundance of vegetation in the  ... 
doi:10.1029/2011jg001886 fatcat:vwhi3gkjefatdcgzm66mt7qwai

Evaluation of the Plant Phenology Index (PPI), NDVI and EVI for Start-of-Season Trend Analysis of the Northern Hemisphere Boreal Zone

Paulina Karkauskaite, Torbern Tagesson, Rasmus Fensholt
2017 Remote Sensing  
[50] concluded that the derivative method is misleading for areas with snow cover on the forest floor as there is then two points in time with an increase in the phenology signal, one coinciding with  ...  to minimize the snow influence on vegetation signal and increase the sensitivity to minor seasonal variation in dense canopy greenness of the boreal forests [36] .  ... 
doi:10.3390/rs9050485 fatcat:tz424rvrvjadzcbfqdn6r566bi

Albedo estimates for land surface models and support for a new paradigm based on foliage nitrogen concentration

2010 Global Change Biology  
Here, we calculated growing season albedos for deciduous and evergreen forests, crops, and grasslands based on over 40 site-years of data from the AmeriFlux network and compared them with estimates presently  ...  used in the land surface formulations of a variety of climate models.  ...  the USDA Forest Service Northern Research Station.  ... 
doi:10.1111/j.1365-2486.2009.02028.x fatcat:ebkzcb2km5ampfoptvmh5dd63m

Characterization of forest types in Northeastern China, using multi-temporal SPOT-4 VEGETATION sensor data

Xiangming Xiao, Stephen Boles, Jiyuan Liu, Dafang Zhuang, Mingliang Liu
2002 Remote Sensing of Environment  
The VGT forest map was compared to estimates of forest area derived from Landsat 7 Enhanced Thematic Mapper (ETM+) images.  ...  Analysis of NDVI and NDWI over the plant growing season allows for the identification of distinct growth patterns between the different forest types.  ...  We thank the three anonymous reviewers for their comments and suggestions on the earlier version of the manuscript.  ... 
doi:10.1016/s0034-4257(02)00051-2 fatcat:a64tngdjljg2vhmfcveixjkwai

Improved Characterisation of Vegetation and Land Surface Seasonal Dynamics in Central Japan with Himawari-8 Hypertemporal Data

Tomoaki Miura, Shin Nagai, Mika Takeuchi, Kazuhito Ichii, Hiroki Yoshioka
2019 Scientific Reports  
In this study, we evaluated improvements in capturing vegetation seasonal changes with 10-min resolution NDVI data derived from Advanced Himawari Imager (AHI), one of new-generation geostationary satellite  ...  in vegetation and snow cover conditions in finer detail with more certainty than those obtained from Visible Infrared Imaging Radiometer Suite (VIIRS), one of the latest polar-orbiting satellite sensors  ...  Acknowledgements This study was supported partially by a Japan Society for the Promotion of Science (JSPS) Invitational Fellowship (ID No.  ... 
doi:10.1038/s41598-019-52076-x pmid:31666582 pmcid:PMC6821777 fatcat:u4fktxpjg5fjrimh6xgc4pzhka

Land use/land cover classification using time series Landsat 8 images in a heavily urbanized area

Ziwei Deng, Xiang Zhu, Qingyun He, Lisha Tang
2019 Advances in Space Research  
The accuracy of the land cover map derived from remote sensing data depends on the spatial resolution of data.  ...  At site scale, comparing to ground truth maps derived from different sources, fragmentation in landscapes is a fundamental problem encountered in the use of MODIS products [33] .  ... 
doi:10.1016/j.asr.2018.12.005 fatcat:cdlqefylofc2lcegvyujz6ntle

Exploiting Growing Stock Volume Maps for Large Scale Forest Resource Assessment: Cross-Comparisons of ASAR- and PALSAR-Based GSV Estimates with Forest Inventory in Central Siberia

Christian Hüttich, Mikhail Korets, Sergey Bartalev, Vasily Zharko, Dmitry Schepaschenko, Anatoly Shvidenko, Christiane Schmullius
2014 Forests  
In this paper, we assess the information content of GSV estimates in Central Siberian forests obtained at 25 m from ALOS-PALSAR and 1 km from ENVISAT-ASAR backscatter data.  ...  Cross-comparisons of multiple SAR-based GSV estimates helped to detect OPEN ACCESS Forests 2014, 5 1754 inconsistencies in the forest inventory data and can support an update of outdated forest inventory  ...  This paper was realized in the framework of the FP 7 EU-Russia ZAPÁS project on the assessment and monitoring of forest resources in Central Siberia.  ... 
doi:10.3390/f5071753 fatcat:mtlyyrnp3za5ngiotok73tmvhi

Multisensor NDVI-Based Monitoring of the Tundra-Taiga Interface (Mealy Mountains, Labrador, Canada)

Élizabeth Simms, Heather Ward
2013 Remote Sensing  
An encroachment of the forest on the tundra for the whole study area was estimated at 0 to 60 m, depending on the period of observation, as calculated by the difference between the median retreat and advance  ...  On the other hand, higher spatial resolution images provide information necessary to understand structural components of the TTI, such as tree islands, functional plant type heterogeneity and forest annual  ...  Acknowledgements We acknowledge funding from the Government of Canada Program for International Polar Year as part of the project Present processes, Past changes, Spatiotemporal dynamics (PPS) Arctic Canada  ... 
doi:10.3390/rs5031066 fatcat:4uelz5fikjfp7cpixnhksv4j64
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