Search results for "VEGETATION"
showing 10 items of 1069 documents
Probabilistic and preferential sampling approaches offer integrated perspectives of Italian forest diversity
2023
Aim: Assessing the performances of different sampling approaches for documenting community diversity may help to identify optimal sampling efforts and strategies, and to enhance conservation and monitoring planning. Here, we used two data sets based on probabilistic and preferential sampling schemes of Italian forest vegetation to analyze the multifaceted performances of the two approaches across three major forest types at a large scale. Location: Italy. Methods: We pooled 804 probabilistic and 16,259 preferential forest plots as samples of vascular plant diversity across the country. We balanced the two data sets in terms of sizes, plot size, geographical position, and vegetation types. F…
Impact of Structural, Photochemical and Instrumental Effects on Leaf and Canopy Reflectance Variability in the 500–600 nm Range
2021
Current rapid technological improvement in optical radiometric instrumentation provides an opportunity to develop innovative measurements protocols where the remote quantification of the plant physiological status can be determined with higher accuracy. In this study, the leaf and canopy reflectance variability in the PRI spectral region (i.e., 500–600 nm) is quantified using different laboratory protocols that consider both instrumental and experimental set-up aspects, as well as canopy structural effects and vegetation photoprotection dynamics. First, we studied how an incorrect characterization of the at-target incoming radiance translated into an erroneous vegetation reflectance spectru…
Weed vegetation of cereal crops in Tajikistan (Pamir Alai Mts., Middle Asia)
2013
The paper presents results of investigations of weed vegetation conducted in crop fields, in Tajikistan (Middle Asia) - one of the world cradles of the weed flora. The study has been based on 299 phytosociological relevés obtained in various geobotanical regions of the country in 2009-2012. In the examined vegetation patches 469 vascular plant species were noted. Many of the recorded species are widespread weeds. However, there were also some rare and endemics taxa (e.g. Prangos pabularia, P. saraw-schanica and Thlaspidium thlaspi) observed in the sample plots. The collected material presents probably, the majority of the variability among the weed communities of crop cultivations in the Mi…
Particle tracking in a gap of aquatic vegetation meadow
2009
Aquatic vegetation considerably affects the flow field in water bodies, with influence increasing as the depth decreases. As a consequence, vegetation also affects suspended particle transport. In inshore sandy beds less than 40 m deep of the Mediterranean Sea, meadows of Posidonia oceanica are widespread. This plant is constituted by a tuft of very thin and flexible ribbon-like leaves about 1 cm wide and up to 1.5 m long; the meadow areal density can reach 1000-1200 plant/m2. Frequently, such meadows are not continuous but vegetated areas alternate with sand strips (“gaps”). The presence of such discontinuities noticeably affects the flow field and gaps can actually act as particle traps. …
Hyperspectral imaging based biomass and nitrogen content estimations from light-weight UAV
2013
Hyperspectral imaging based precise fertilization is challenge in the northern Europe, because of the cloud conditions. In this paper we will introduce schemes for the biomass and nitrogen content estimations from hyperspectral images. In this research we used the Fabry-Perot interferometer based hypespectral imager that enables hyperspectral imaging from lightweight UAVs. During the summers 2011 and 2012 imaging and flight campaigns were carried out on the Finnish test field. Estimation mehtod uses features from linear and non-linear unmixing and vegetation indices. The results showed that the concept of small hyperspectral imager, UAV and data analysis is ready to operational use.
Implementation of IUCN criteria for the definition of the Red List of Ecosystems in Italy, Plant Biosystems.
2020
The present work is aimed at presenting the data, methods and criteria that are being used for the assessment of ecosystem collapse risk in Italy.
The legacy of human use in Amazonian palm communities along environmental and accessibility gradients
2023
Aim: Palms are iconic and dominant elements of neotropical forests. In the Amazon region, palms have been used and managed by humans for food, material, medicine and other purposes for millennia. It is, however, debated to what extent the structure of modern palm communities reflects long-term human modification. Here, we investigate the complex interplay of ecological and societal factors that influence the distributions of both human-used and non-used palms in western Amazonia. Location: Amazonia. Time period: Present. Major taxa studied: Palms (Arecaceae). Methods: We used Bayesian hierarchical joint species distribution models to predict the distributions and environmental niche dimensi…
Effect of the submerged vegetation distribution on flow characteristics and lateral dispersion: Experimental analysis at the apex section of a meande…
2020
Understanding of how the vegetation distribution influences flow patterns and turbulence structure is extremely important to analyse environmental processes as the sediment transport and the mixing of transported quantities. In the present paper attention is focused on the effect of flexible vegetation on flow characteristics and dispersion processes at the apex section of a large-amplitude meandering bend. The analysis is conducted with the aid of data collected in a laboratory meandering flume both in the absence of vegetation on the bed and in the presence of real and flexible vegetation on the bed. Results show that the presence of vegetation affects both the lateral dispersion coeffici…
Relationships between Heavy Metal Concentrations in Greater Celandine (Chelidonium majus L.) Tissues and Soil in Urban Parks
2023
Anthropogenic ecological ecosystems create favourable conditions for the growth of the nitrophilous medicinal species Chelidonium majus in six urban parks in Southern Poland. This study focuses on the concentrations of trace elements in the soils, leaves, stems, and rhizomes of greater celandine. The soil samples were taken only in the humus horizon (A), which averaged approximately 15 cm in thickness under the clumps of Ch. majus. Regarding the reaction, the soil samples tested can be described as slightly acidic (5.6–6.8 in KCl) to alkaline (7.1–7.4 in H2O). Organic carbon content at all sites is high, ranging from 3.2% to 13.6%, while the highest total nitrogen (Nt) content is 0.664%. Th…
Revegetation through hydroseeding in degraded Mediterranean areas
2012
Hydroseeding is a technique increasingly used to establish vegetation on degraded areas in order to perform environmental protection. The objective of this paper was to evaluate the effectiveness of four different hydroseeding methods on a degraded artificial slope in the southern Mediterranean area determining total vegetation cover, hydroseeding vegetation cover, hydroseeding success index (HSI), natural and hydroseeded vegetation height. The test area does not allow the use of any operating machine for soil and vegetation management, the only applicable technique is therefore hydroseeding. After hydroseeding was applied (December 2010), 21 checks were carried out every 15 days (from Janu…