A5077479187- Remote Sensing in Agriculture
- Remote Sensing and LiDAR Applications
- Plant Water Relations and Carbon Dynamics
- Leaf Properties and Growth Measurement
- Forest ecology and management
- Land Use and Ecosystem Services
- Species Distribution and Climate Change
- Remote Sensing and Land Use
- Ecology and Vegetation Dynamics Studies
- Atmospheric and Environmental Gas Dynamics
- Satellite Image Processing and Photogrammetry
- Plant responses to elevated CO2
- Plant and animal studies
- Calibration and Measurement Techniques
- Climate variability and models
- Urban Heat Island Mitigation
- Botany and Plant Ecology Studies
- Tree-ring climate responses
- Climate change and permafrost
- Plant Ecology and Soil Science
- Cryospheric studies and observations
- Fire effects on ecosystems
- Horticultural and Viticultural Research
- Soil Geostatistics and Mapping
- Mediterranean and Iberian flora and fauna
Tartu Observatory
2015-2024
University of Tartu
2018-2024
Institute of Geographic Sciences and Natural Resources Research
2016
Chinese Academy of Sciences
2016
Water Insight (Netherlands)
2014
University of Toronto
2006-2012
Metsähallitus (Finland)
2011
Sunlit and shaded leaf separation proposed by Norman (1982) is an effective way to upscale from canopy in modeling vegetation photosynthesis. The Boreal Ecosystem Productivity Simulator (BEPS) makes use of this methodology, has been shown be reliable the gross primary productivity (GPP) derived CO 2 flux tree ring measurements. In study, we BEPS investigate effect architecture on global distribution GPP. For purpose, not only area index (LAI) but also first ever map foliage clumping...
Leaf area index (LAI) is one of the most important Earth surface parameters in modeling ecosystems and their interaction with climate. Based on a geometrical optical model (Four-Scale) LAI algorithms previously derived for Canada-wide applications, this paper presents new algorithm global retrieval where bidirectional reflectance distribution function (BRDF) considered explicitly hence removing need doing BRDF corrections normalizations to input images. The core problem integrating into that...
NASA's Global Ecosystem Dynamics Investigation (GEDI) is collecting spaceborne full waveform lidar data with a primary science goal of producing accurate estimates forest aboveground biomass density (AGBD). This paper presents the development models used to create GEDI's footprint-level (~25 m) AGBD (GEDI04_A) product, including description datasets and procedure for final model selection. The fit our are from compilation globally distributed spatially temporally coincident field airborne...
As Earth's climate has varied strongly through geological time, studying the impacts of past change on biodiversity helps to understand risks from future change. However, it remains unclear how paleoclimate shapes spatial variation in biodiversity. Here, we assessed influence Quaternary dissimilarity taxonomic, phylogenetic, and functional composition among neighboring 200-kilometer cells (beta-diversity) for angiosperm trees worldwide. We found that larger glacial-interglacial temperature...
Leaf angle distribution (LAD) is an important property which influences the spectral reflectance and radiation transmission properties of vegetation canopies, hence interception, absorption photosynthesis. It a fundamental parameter radiative transfer models at all scales. Yet, difficulty in measuring LAD causes it to be also one most poorly characterized parameters, typically either assumed random, or follow very small number parametric 'archetype' functions. Terrestrial LiDAR scanning...
Safeguarding Earth's tree diversity is a conservation priority due to the importance of trees for biodiversity and ecosystem functions services such as carbon sequestration. Here, we improve foundation effective global by analyzing recently developed database species covering 46,752 species. We quantify range protection anthropogenic pressures each develop priorities across taxonomic, phylogenetic, functional dimensions. also assess effectiveness several influential proposed prioritization...
BackgroundAngular distribution of leaves is a major determinant radiation transmittance through the canopy.Leaf inclination angle plays fundamental role in leaf projection function (commonly referred to as G-function), which turn key variable for indirect quantification area index (Ross 1981).To date, relatively few measurements have been reported different tree species; compilation large datasets has long hampered due issues consistently applying existing methods canopies, difficulty direct...
The spatial and temporal patterns of the forest background reflectance are critically important for retrieving biophysical parameters canopy (overstory) ecosystem modeling. In this short communication paper, we retrieved seasonal courses understory Normalized Difference Vegetation Index (NDVI) from MODIS BRDF data using semi-empirical physically-based approach. We compared satellite-based NDVI series to measured in forests three full growing seasons boreal hemiboreal sites Northern Europe....
Abstract. Forest overstory and understory layers differ in carbon water cycle regimes phenology, as well ecosystem functions. Separate retrievals of leaf area index (LAI) for these two would help to improve modeling forest biogeochemical cycles, evaluating functions also remote sensing canopies by inversion canopy reflectance models. In this paper, LAI values were estimated separately global needleleaf deciduous broadleaf forests fusing MISR MODIS observations. Monthly was retrieved from the...