49 research outputs found
The use of vegetation series to assess ĂĄ and Ăą vegetation diversity and their relationships with geodiversity in the province of Almeria (Spain) with watersheds as operational geographic units
Abstract With this paper we suggest that vegetation series is a useful conceptual tool to identify a clear level of biodiversity of land systems among the many possible logical levels. The suggestion is supported by the results of a case study carried out for the province of Almeria (Spain) using the watersheds as operational geographic units. The application of standard correlation analysis, simple and partial, the Mantel?s test, and the cluster analysis has shown that ? and ? vegetation diversities, based on vegetation series, are significantly predictive with respect to environmental heterogeneity expressed by pedodiversity, lithodiversity, and some parameters of digital elevation model. Being a product of the Braun Blanquet?s floristic approach, vegetation series could be the key to enter into vegetation databases for biodiversity analysis of land systems at many other levels of knowledge. Keywords: data mining, Mantel, nestedness, partial correlation, pedodiversity, Simpson, knowledge generatio
Using spatial data mining to analyze area-diversity patterns among soil, vegetation, and climate: A case study from AlmerĂa, Spain
ABSTRACT: Area-pedodiversity, area?vegetation diversity, area-bioclimatic belts, diversity and pedodiversity-vegetation diversity-bioclimatic diversity relationships were analyzed for the most arid region ofWestern Europe (SE Spain). The study is novel in that it analyzed these relationships using as operational geographic units (OGUs) the set of polygons belonging to the same character state (i.e., typology) that defines a zone in a given thematic map. We considered three thematic maps: 1) the map of soil associations (SMU) with 303 different soil associations (i.e., 303 areas or zones); 2) the map of potential vegetation (PNV)with 40 vegetation series or zones and 3) the map of bioclimatic belts (BB) with 7 bioclimatic zones. Using GIS tools, we analyzed the contents (richness) of soil mapping units (polygons) with regard to vegetation series and bioclimatic belts as well as the contents of vegetation series and bioclimatic belts with regard to SMU. The results indicate that the relationships between the area and the richness of zones follow a power law, the ?fingerprint of fractal geometry?, irrespective of the way the area has been defined and their relative magnitude (the areas defined by SMU are the smallest, while the areas defined by bioclimatic belts are the largest). The results also indicate a significant correlation between the ? diversities of the zones and between their ? diversities. We conclude that the methods used to measure such correlations, based on ? and ? diversities are useful to investigate and quantify the relationships between the pedosphere, vegetation and climate
Double down on remote sensing for biodiversity estimation: a biological mindset
In the light of unprecedented planetary changes in biodiversity, real-time and accurate ecosystem and biodiversity assessments are becoming increasingly essential for informing policy and sustainable development. Biodiversity monitoring is a challenge, especially for large areas such as entire continents. Nowadays, spaceborne and airborne sensors provide information that incorporate wavelengths that cannot be seen nor imagined with the human eye. This is also now accomplished at unprecedented spatial resolutions, defined by the pixel size of images, achieving less than a meter for some satellite images and just millimeters for airborne imagery. Thanks to different modeling techniques, it is now possible to study functional diversity changes over different spatial and temporal scales. At the heart of this unifying framework are the âspectral speciesââsets of pixels with a similar spectral signalâand their variability over space. The aim of this paper is to summarize the power of remote sensing for directly estimating plant species diversity, particularly focusing on the spectral species concept
From zero to infinity: Minimum to maximum diversity of the planet by spatio-parametric Rao's quadratic entropy
Aim: The majority of work done to gather information on the Earth's biodiversity has been carried out using in-situ data, with known issues related to epistemology (e.g., species determination and taxonomy), spatial uncertainty, logistics (time and costs), among others. An alternative way to gather information about spatial ecosystem variability is the use of satellite remote sensing. It works as a powerful tool for attaining rapid and standardized information. Several metrics used to calculate remotely sensed diversity of ecosystems are based on Shannonâs information theory, namely on the differences in relative abundance of pixel reflectances in a certain area. Additional metrics like the Raoâs quadratic entropy allow the use of spectral distance beside abundance, but they are point descriptors of diversity, that is they can account only for a part of the whole diversity continuum. The aim of this paper is thus to generalize the Raoâs quadratic entropy by proposing its parameterization for the first time.
Innovation: The parametric Raoâs quadratic entropy, coded in R, (a) allows the representation of the whole continuum of potential diversity indices in one formula, and (b) starting from the Raoâs quadratic entropy, allows the explicit use of distances among pixel reflectance values, together with relative abundances.
Main conclusions: The proposed unifying measure is an integration between abundance- and distance-based algorithms to map the continuum of diversity given a satellite image at any spatial scale. Being part of the rasterdiv R package, the proposed method is expected to ensure high robustness and reproducibility
Some aspects of classification and ordination of vegetation data in perspective
A discussion on the complementarity of classification and ordination methods in vegetation ecology is given. The need to work with different vegetation spaces and hierarchical processes is stressed
Ordine e disordine nella natura: uomini e biomi
Enrico Feoli cercherĂ di rispondere da un punto di vista ecologico alle domande âCosa Ăš per noi lâordine? Cosa il disordine? Come possiamo misurarli?â, sulla base dei suoi studi di ecologia delle comunitĂ vegetali e del territorio antropizzato in varie parti del mondo. Il concetto di nicchia ecologica a diversi livelli gerarchici verrĂ confrontato con il concetto di idoneitĂ o opportunitĂ nell'evoluzione dei sistemi viventi all'interno dei diversi biomi.Enrico Feoli ha rivestito il ruolo di Professore Ordinario di Ecologia presso lâUniversitĂ degli studi di Trieste, ed ha insegnato Ecologia quantitativa al MAICH, Chania, GR (International Centre for Advanced Mediterranean Agronomic Studies, Paris Rue Newton 11, 75116, France). Le sue ricerche hanno riguardato lâapplicazione di metodi matematici e statistici allo studio della vegetazione e alle sue interazioni con il clima, lâintegrazione dellâinformazione e le conoscenze ecologiche e socioeconomiche nei processi di decisione nella gestione delle risorse naturali al fine dello sviluppo sostenibile. Ă stato inoltre ricercatore e professore ospite in diverse universitĂ in Africa, China, Europa, India, Nord America ed ha curato per molti anni il programma ambientale dellâICS-UNIDO (Trieste). Ă stato il fondatore del Centro Internazionale di Ecologia Teorica ed Applicata (CETA, Gorizia), di cui Ăš membro onorario del comitato scientifico; ha fatto parte ed Ăš tuttora membro di comitati nellâambito di redazioni di numerose riviste scientifiche nazionali ed internazionali
Heath species and heathlands of Italy: an analysis of their relationships under the perspective of climate change based on the description of habitats used for the project âCarta della Naturaâ (Italian Map of Nature).
1The project âItalian Map of Natureâ (IMN) is dedicated to create an electronic map (GIS) of the environmental state
(quality and vulnerability) of the Italian territory at different scales. Up to now the GIS of IMN is offering maps at a scale 1:50,000.
The environmental quality is estimated on the basis of biological description of habitats that can be mapped at this scale, the vulner-
ability on the basis of variables related to the anthropogenic pressure. In this paper I want to show that the information collected for
creating the data base of habitats for mapping purposes may be useful for getting information related to the climatic niche width of
the species considered habitat indicators. In this paper I consider the heath species characterizing the IMN habitats of Italy in order
to get an indirect estimation of the climatic vulnerability of Italian heathlands. To measure the climatic niche width of the species
I propose a formula that combines the number of habitats (they characterize) with the heterogeneity of the habitats according to their
distribution in altitudinal belts and in biogeographic regions. The results offer parameters on which to base a discussion for policy
conservation of heaths and heathlands in Italy under the perspective of climate change.nonemixedFeoli E.Feoli, Enric