Fig 4 - uploaded by Franco Pedrotti
Content may be subject to copyright.
Source publication
A sigmetum, as described in Chap. 6, is a local assemblage of all the communities that have the potential to develop toward a particular single climax. A geosigmetum is the system of multiple sigmeta along a gradient, which in a landscape may correspond to a catena. Synphytosociology is the phytosociology of sigmeta, i.e. the analytical classificat...
Citations
... Accordingly, mapping methods play a central role in biogeographical questions, increasing or decreasing the inner complexity of their interpretation. Apart from the general cognitive capacity of researchers to look at and search on maps [6][7][8][9], the interpretation of plant species ranges is strongly connected with other disciplines and depends on data quantity and quality, as well as on representation methods and techniques [10]. ...
Species mapping methods play a central role in biogeographical questions, as they may generate a domino effect on further works based on species distribution. In light of the massive recent increase in the availability of online occurrence data, we highlight the strengths and limitations of the mapping methods most widely used to display the geographic distribution of plants, namely geographic range maps and occurrence record maps. We use the modern distribution of the genus Arbutus in western Eurasia, North Africa, and Macaronesia, for which no occurrence record map has been published yet, to discuss critical issues in data collection and representation. The occurrence record map of A. unedo, A. andrachne, A. canariensis, and A. pavarii shows how well this mapping method captures the details of peripheral and isolated stands as well as the variability of population density. A number of biogeographical issues are addressed by this approach, including the determination of the chorological centre of gravity in relation to historical dynamics, genetic patterns in relation to range porosity, and the autochthony status of marginal stands. These issues constitute the necessary foundation for additional palaeobotanical research and ecological modelling to investigate the past-to-future dynamics of Arbutus and other species of the Mediterranean–Atlantic area.
... Phytogeographic research has been closely associated with the different ways of representing vegetation. Much of the debate has centred on how to conceptualize an entity or unit of vegetation in a way that, despite involving a degree of abstraction, can successfully express the reality of plant life, as verifiable on the ground (Bohn et al., 2005;Braun-Blanquet, 1979;Franklin, 2013;Gaussen, 1961;Pedrotti, 2013;Whittaker, 1978). The representation of potential vegetation, normally executed at small and medium scale (1:200,000 and smaller), has opted for solutions based on more general and/or abstract notions related with bioclimate, altitude, soil conditions, vegetation series and the most important azonal types of vegetation (Bohn et al., 2000-03;Rivas-Martínez, 1987). ...
... After this process, we reached a synthesis with 35 definitive categories (Main Map). Specialized manuals were consulted (Cauvin et al., 2010;Gaussen, 1961;Küchler, 1967;Pedrotti, 2013) in relation to the application of the principles of basic map drafting (design, generalization, drafting) and thematic maps (use of visual variables, etc.). ...
In this paper, we present a map of the current state of vegetation and land use in a UTM square measuring 10 × 10 km in Utande (La Alcarria, Central Spain) at a semi-detailed scale of 1:20,000. The map presented here offers an example of how to carry out a series of maps of the plant landscape, using regular grid squares of 100 km² (hectads). The map was drawn up using a cartographic method scaled in levels, which can be updated in line with advances in territorial tracking, and enabled us to group together synthetic categories adapted to the biogeographical idiosyncrasy of territory. We recommend combining this phytocoenotic study with another focusing on the flora and the chorology in the same space. A map was obtained with 35 categories, which offers a large-scale image of the biophysical land covers. This will be useful for territorial planning and biodiversity protection.
... A seguito dell'indagine vegetazionale, è stata effettuata la cartografia della vegetazione delle due "lame", ad elevato dettaglio di rilevamento mediante software ArcMap tramite fotointerpretazione a partire da ortofoto del 2007 e con l'ausilio dei rilievi della vegetazione svolti in campo a fine luglio 2010. Il rilevamento cartografico ha seguito la metodologia applicata in precedenti studi della vegetazione (Pignatti 1995;Pedrotti 2012). La carta è restituita in scala 1:500 sulla base della C.T.R. 1:5000 messa a disposizione dalla Regione Veneto. ...
The present work concerns the analysis of flora and vegetation of two wetlands, locally called "lame", located in the Cansiglio Plain (BL-Italy) in an area characterized by grazing. Moreover, pH and electrical conductance of soil and water samples have been measured. These two "lame" are so called Lamaràz (a mire) and Lama Lissandri (a pond). Floristic surveys brought to the overall identification of 103 vascular plant species and 4 Bryophyte (3 Sphagnum species and 1 moss). In the lama Lissandri were observed 4 species not recorded before. The vegetation relevé suggested to attribute to the Lamaràz two tipical mire vegetation classes (Scheuchzerio-Caricetea nigrae and cfr. Oxycocco-Sphagnetea), while the vegetation of the pool is included into the classes Phragmiti-Magnocaricetea, Bidentetea tripartiti and Potametea. By means of pH and electric conductivity measurements, it was possible to relate the variations in these two ecological parameters with the observed changes in vegetation. The results show a belt disposition of vegetation types in the Lamaràz, following the relevant ecological gradients. On the other hand, the Lama Lissandri showed a fragmented and heterogeneous pattern, due to anthropogenic pressures. To this characteristic is associated a high floristic richness.
Vegetation is a key biosphere component to supporting biodiversity on Earth, and its maintenance and proper functioning are essential to guarantee the well-being of humankind. From a broad perspective, a fundamental goal of vegetation ecology is to understand the roles of abiotic and biotic factors that affect vegetation structure, distribution, diversity, and functioning, considering the relevant spatial and temporal scales. In this contribution, we reflect on the difficulties and opportunities to accomplish this grand objective by reviewing recent advances in the main areas of vegetation ecology. We highlight theoretical and methodological challenges and point to alternatives to overcome them. Our hope is that this contribution will motivate the development of future research efforts that will strengthen the field of vegetation ecology. Ultimately, vegetation science will continue to provide a strong knowledge basis and multiple theoretical and technological tools to better face the current global environmental crisis and to address the urgent need to sustainably conserve the vegetation cover of our planet in the Anthropocene.
Aim
Many countries lack informative, high‐resolution, wall‐to‐wall vegetation or land cover maps. Such maps are useful for land use and nature management, and for input to regional climate and hydrological models. Land cover maps based on remote sensing data typically lack the required ecological information, whereas traditional field‐based mapping is too expensive to be carried out over large areas. In this study, we therefore explore the extent to which distribution modelling ( DM ) methods are useful for predicting the current distribution of vegetation types ( VT ) on a national scale.
Location
Mainland Norway, covering ca. 324,000 km ² .
Methods
We used presence/absence data for 31 different VT s, mapped wall‐to‐wall in an area frame survey with 1081 rectangular plots of 0.9 km ² . Distribution models for each VT were obtained by logistic generalised linear modelling, using stepwise forward selection with an F ‐ratio test. A total of 116 explanatory variables, recorded in 100 m × 100 m grid cells, were used. The 31 models were evaluated by applying the AUC criterion to an independent evaluation dataset.
Results
Twenty‐one of the 31 models had AUC values higher than 0.8. The highest AUC value (0.989) was obtained for Poor/rich broadleaf deciduous forest , whereas the lowest AUC (0.671) was obtained for Lichen and heather spruce forest . Overall, we found that rare VT s are predicted better than common ones, and coastal VT s are predicted better than inland ones.
Conclusions
Our study establishes DM as a viable tool for spatial prediction of aggregated species‐based entities such as VT s on a regional scale and at a fine (100 m) spatial resolution, provided relevant predictor variables are available. We discuss the potential uses of distribution models in utilizing large‐scale international vegetation surveys. We also argue that predictions from such models may improve parameterisation of vegetation distribution in earth system models.
Vegetation maps have been key tools for synthesizing large amounts of information and supporting geographical location of biodiversity. Traditional vegetation map development demands acquisition and processing of expensive supplies, expertise of qualified interpreters and extensive fieldwork; nevertheless vegetation maps are crucial in areas where conservation policies ought to be rapidly produced, as it is the case of the Tehuacán-Cuicatlán Valley which was recently declared a hotspot of biocultural heritage of highly important conservation. Currently, mapping approaches that integrate plant diversity outcomes, expert knowledge and land cover information are still scarce. In this study we combined free access cartographic data and expert knowledge to develop a vegetation map, in order to provide basic criteria for decisions on conservation of regional biocultural diversity. Bioclimatic regionalization, georeferenced fieldwork, over 30 years of vegetation outcomes and expert knowledge enabled us to develop a novel method for vegetation mapping. Climatic, lithologic and topographic affinities were used as main criteria for map class reassignment. Field verification allowed quantifying an acceptable certainty of class assignation. Our comprehensive approach proved fundamental for developing a detailed vegetation map elucidating complex vegetation diversity patterns. The classification scheme here proposed increased almost twofold that of the original land cover map. Regarding the outstanding plant diversity harbored, the extent of the study area (~ 12 000 km²) and the scale of the vegetation map obtained, we regarded the map certainty as meaningful. To conclude, the present vegetation map proved to be a powerful communication tool to facilitate sound conservation policy making.
