Search results for " VEGETATION"

Revision of Nymphaea candida range - New DATA on the distribution and habitat preferences of the species in Southern Poland

2011

The paper presents results of geobotanical and taxonomic studies on the distribution and habitat requirements of <em>Nymphaea candida</em> in southern Poland. The researches were conducted in southern Poland in 2003-2009, in the provinces of Lower Silesia, Lublin, Małopolska, Opole, Silesian province as well as, in southern parts of Mazowieckie and Lubuskie. Flowers, leaves and fruits of <em>Nymphaea</em> species were collected from 27 locations. Altogether pollens from 73 populations of <em>N. candida</em> and 18 of <em>N. alba</em> from all the researched area were measured. The trophic level of an ecosystem was evaluated according to the re…

Note illustrative alla carta geomorfologica e della vegetazione dell’area della Rocchetta.

2003

Note illustrative alla carta geomorfologica e della vegetazione del conoide dell’Avisio.

2003

Validation of a mapping and prediction model for human fasciolosis transmission in Andean very high altitude endemic areas using remote sensing data.

2001

The present paper aims to validate the usefulness of the Normalized Difference Vegetation Index (NDVI) obtained by satellite remote sensing for the development of local maps of risk and for prediction of human fasciolosis in the Northern Bolivian Altiplano. The endemic area, which is located at very high altitudes (3800-4100 m) between Lake Titicaca and the valley of the city of La Paz, presents the highest prevalences and intensities of fasciolosis known in humans. NDVI images of 1.1 km resolution from the Advanced Very High Resolution Radiometer (AVHRR) sensor on board the National Oceanic and Atmospheric Administration (NOAA) series of environmental satellites appear to provide adequate …

Botanical excursions in central and Western Sicily - Field Guide For the 60th IAVS Symposium

2017

A generalized soil-adjusted vegetation index

2002

Operational monitoring of vegetative cover by remote sensing currently involves the utilisation of vegetation indices (VIs), most of them being functions of the reflectance in red (R) and near-infrared (NIR) spectral bands. A generalized soil-adjusted vegetation index (GESAVI), theoretically based on a simple vegetation canopy model, is introduced. It is defined in terms of the soil line parameters (A and B) as: GESAVI=(NIRBRA)/(R+Z), where Z is related to the red reflectance at the cross point between the soil line and vegetation isolines. As Z is a soil adjustment coefficient, this new index can be considered as belonging to the SAVI family. In order to analyze the GESAVI sensitivity to s…

Vegetation growth parameters and leaf temperature: Experimental results from a six plots green roofs' system

2016

Abstract The paper provides a contribution for populating database of three physical parameters needed to model energy performance of buildings with green roofs: “coverage ratio” ( σ f ), leaf area index (LAI) and leaf temperature ( T f ). On purpose, six plant species were investigated experimentally: Phyla nordiflora, Aptenia lancifolia , Mesembryanthenum barbatus , Gazania nivea, Gazania uniflora , and Sedum . Proper ranges of the cited parameters have been found for each species. The here indicated ranges of σ f values refer to different growth levels of the species in the same lapse of time, that is four months. Single measured LAI values are also reported for the same plants. As for t…

L'acacia au Sénégal

1996

La biodiversité des Glomales associés à #Acacia albida$ est étudiée en fonction de l'âge de l'arbre, des saisons et des propriétés physicochimiques du sol. Les Glomales sont récoltées jusqu'à 1,5 et 4,5 m dans les régions soudano-guinéennes et jusqu'à 16 et 35 m dans les régions sahéliennes. La culture in vitro de la forme intraracinaire des Glomales en présence de racines isolées a montré une diversité morphologique des souches. En complément à cette taxonomie morphologique, des marqueurs moléculaires ont permis d'étudier la variabilité génétique des Glomales en comparant les variations de séquences d'ADN extrait de spores et de fragments mycorhiziens. (Résumé d'auteur)

Phytosociological remarks on residual woodlands of Laurus nobilis in Sicily

2010

A phytosociological study was done of Laurus nobilis woodlands in Sicily. The analysis, based on 18 relevés, supports the definition of a new syntaxon (Acantho mollis-Lauretum nobilis ass. nov.), considered as a vicariant of similar vegetation aspects described in other Mediterranean areas (Iberian and Italian peninsulas). The study mainly includes some unpublished sites where polycormic individuals of laurel, sometimes reaching 13-15 meters in height, dominates the tree layer. This vegetation is also characterized by some laurophyllous species (Hedera helix, Rhamnus alaternus, Smilax aspera and sometimes Viburnum tinus) and lianas (Rubia peregrina var. longifolia, Asparagus acutifolius, Ta…

Quantifying the Robustness of Vegetation Indices through Global Sensitivity Analysis of Homogeneous and Forest Leaf-Canopy Radiative Transfer Models

2019

Vegetation indices (VIs) are widely used in optical remote sensing to estimate biophysical variables of vegetated surfaces. With the advent of spectroscopy technology, spectral bands can be combined in numerous ways to extract the desired information. This resulted in a plethora of proposed indices, designed for a diversity of applications and research purposes. However, it is not always clear whether they are sensitive to the variable of interest while at the same time, responding insensitive to confounding factors. Hence, to be able to quantify the robustness of VIs, a systematic evaluation is needed, thereby introducing a widest possible variety of biochemical and structural heterogeneit…