BACKGROUND Canopy structure, which can be defined as the sum of the sizes, shapes and relative placements of the tree crowns in a forest stand, is central to all aspects of forest ecology. But there is no accepted method for deriving canopy structure from the sizes, species and biomechanical properties of the individual trees in a stand. Any such method must capture the fact that trees are high...

Gross canopy photosynthesis (P(g)) can be simulated with canopy models or retrieved from turbulent carbon dioxide (CO2) flux measurements above the forest canopy. We compare the two estimates and illustrate our findings with two case studies. We used the three-dimensional canopy model MAESTRA to simulate P(g) of two spruce forests differing in age and structure. Model parameter acquisition and ...

Validation of Leaf Area Index (LAI) derived from moderate resolution remote sensing observations generally involves optical technique to measure ground LAI. As the current validation datasets are derived using multiple optical retrieval techniques, assessment of the consistency between these techniques is required. In this study the effective Plant Area Index (PAIeff) retrievals by three major ...

The system fertilization approach emerged to improve nutrient use efficiency in croplands. This new concept aims at taking advantage of cycling within an agroecosystem obtain maximum production from each unit. To monitor this effect, methodologies such as the Normalized Difference Vegetation Index (NDVI) are promising evaluate plant biomass and content. We evaluated NDVI a predictor shoot bioma...

Accurate and timely spatiotemporal distribution information of soybean is vital for sustainable agriculture development. However, it challenging to establish a phenology-based automated crops mapping algorithm at large spatial domains by simply applying vegetation index temporal profile. This study developed Phenology-based automatic Soybean through combined Canopy water Chlorophyll variations ...

Validation of Leaf Area Index (LAI) derived from moderate resolution remote sensing observations generally involves optical technique to measure ground LAI. As the current validation datasets are derived using multiple optical retrieval techniques, assessment of the consistency between these techniques is required. In this study the effective Plant Area Index (PAIeff) retrievals by three major ...

In the past, obtaining reliable measurements of key forest canopy metrics has been difficult, even after the development of remote sensing technology. Fortunately, next-generation lidar systems are proving to be useful tools for deriving critical canopy measurements, such as height, structure and biomass. These studies have all focused on empirical comparisons between basic lidar-derived and fi...

A growing number of studies have focused on evaluating spectral indices in terms of their sensitivity to vegetation biophysical parameters, as well as to external factors affecting canopy reflectance. In this context, leaf and canopy radiative transfer models are valuable for modeling and understanding the behavior of such indices. In the present work, PROSPECT and SAILH models have been used t...