Search results for "Vegetation structure"
showing 3 items of 3 documents
Estimation of Vegetation Structure Parameters From SMAP Radar Intensity Observations
2021
In this article, we present a multipolarimetric estimation approach for two model-based vegetation structure parameters (shape A and orientation distribution ψ of the main canopy elements). The approach is based on a reduced observation set of three incoherent (no phase information) polarimetric backscatter intensities (|S HH | 2 , |S HV | 2 , and |S VV | 2 ) combined with a two-parameter (A P and ψ) discrete scatterer model of vegetation. The objective is to understand whether this confined set of observations contains enough information to estimate the two vegetation structure parameters from the L-band radar signals. In order to disentangle soil and vegetation scattering influences on th…
Global L-band vegetation volume fraction estimates for modeling vegetation optical depth
2021
The attenuation of microwave emissions through the canopy is quantified by the vegetation optical depth (VOD), which is related to the amount of water, the biomass and the structure of vegetation. To provide microwave-derived plant water estimates, one must account for biomass/structure contributions in order to extract the water component from the VOD. This study uses Aquarius scatterometer data to build an L-band global seasonality of vegetation volume fraction (d), representative of biomass/structure dynamics. The dynamic range of d is adapted for its application in a gravimetric moisture (Mg) retrieval model. Results show that d ranging from 0 to 3.35.10- 4 is needed for modelling physi…
Shallow waters as ecological corridors: preliminary data on wind-exposure, physico-chemical features and vegetation structure of the Western Sicilian…
2004
The study was carried out in the Natural Reserve of Trapani and Paceco saltworks shallow system (western Sicily: 37° 52’ North; 12° 28’East).The main goal is to deepen our understanding of whether the alteration of the complexity of these particular ecosystems is manifested through a consequent reduction of the number of migrant species and their density. To achieve this, we focalized our attention on organic matter fluxes (in terms of origin and availability for apex consumers), and on the density and distribution of aquatic birds.