A generic process-based SImulator for meditERRanean landscApes (SIERRA): design and validation exercises

2001 ◽  
Vol 147 (1) ◽  
pp. 75-97 ◽  
Author(s):  
Florent Mouillot ◽  
Serge Rambal ◽  
Sandra Lavorel
2020 ◽  
Vol 9 (1) ◽  
Author(s):  
Marina D’Este ◽  
Antonio Ganga ◽  
Mario Elia ◽  
Raffaella Lovreglio ◽  
Vincenzo Giannico ◽  
...  

Abstract Background Wildfires play a key role in shaping Mediterranean landscapes and ecosystems and in impacting species dynamics. Numerous studies have investigated the wildfire occurrences and the influence of their drivers in many countries of the Mediterranean Basin. However, in this regard, no studies have attempted to compare different Mediterranean regions, which may appear similar under many aspects. In response to this gap, climatic, topographic, anthropic, and landscape drivers were analyzed and compared to assess the patterns of fire ignition points in terms of fire occurrence and frequency in Catalonia (Spain), Sardinia, and Apulia (Italy). Therefore, the objectives of the study were to (1) assess fire ignition occurrence in terms of probability and frequency, (2) compare the main drivers affecting fire occurrence, and (3) produce fire probability and frequency maps for each region. Results In pursuit of the above, the probability of fire ignition occurrence and frequency was mapped using Negative Binomial Hurdle models, while the models’ performances were evaluated using several metrics (AUC, prediction accuracy, RMSE, and the Pearson correlation coefficient). The results showed an inverse correlation between distance from infrastructures (i.e., urban roads and areas) and the occurrence of fires in all three study regions. This relationship became more significant when the frequency of fire ignition points was assessed. Moreover, a positive correlation was found between fire occurrence and landscape drivers according to region. The land cover classes more significantly affected were forest, agriculture, and grassland for Catalonia, Sardinia, and Apulia, respectively. Conclusions Compared to the climatic, topographic, and landscape drivers, anthropic activity significantly influences fire ignition and frequency in all three regions. When the distance from urban roads and areas decreases, the probability of fire ignition occurrence and frequency increases. Consequently, it is essential to implement long- to medium-term intervention plans to reduce the proximity between potential ignition points and fuels. In this perspective, the present study provides an applicable decision-making tool to improve wildfire prevention strategies at the European level in an area like the Mediterranean Basin where a profuse number of wildfires take place.


2021 ◽  
Vol 15 (4) ◽  
pp. 1-20
Author(s):  
Georg Steinbuss ◽  
Klemens Böhm

Benchmarking unsupervised outlier detection is difficult. Outliers are rare, and existing benchmark data contains outliers with various and unknown characteristics. Fully synthetic data usually consists of outliers and regular instances with clear characteristics and thus allows for a more meaningful evaluation of detection methods in principle. Nonetheless, there have only been few attempts to include synthetic data in benchmarks for outlier detection. This might be due to the imprecise notion of outliers or to the difficulty to arrive at a good coverage of different domains with synthetic data. In this work, we propose a generic process for the generation of datasets for such benchmarking. The core idea is to reconstruct regular instances from existing real-world benchmark data while generating outliers so that they exhibit insightful characteristics. We propose and describe a generic process for the benchmarking of unsupervised outlier detection, as sketched so far. We then describe three instantiations of this generic process that generate outliers with specific characteristics, like local outliers. To validate our process, we perform a benchmark with state-of-the-art detection methods and carry out experiments to study the quality of data reconstructed in this way. Next to showcasing the workflow, this confirms the usefulness of our proposed process. In particular, our process yields regular instances close to the ones from real data. Summing up, we propose and validate a new and practical process for the benchmarking of unsupervised outlier detection.


2016 ◽  
Vol 111 ◽  
pp. 269-297
Author(s):  
Richard Hodges ◽  
Erika Carr ◽  
Alessandro Sebastiani ◽  
Emanuele Vaccaro

This article provides a short report on a survey of the region to the east of the ancient city of Butrint, in south-west Albania. Centred on the modern villages of Mursi and Xarra, the field survey provides information on over 80 sites (including standing monuments). Previous surveys close to Butrint have brought to light the impact of Roman Imperial colonisation on its hinterland. This new survey confirms that the density of Imperial Roman sites extends well to the east of Butrint. As in the previous surveys, pre-Roman and post-Roman sites are remarkably scarce. As a result, taking the results of the Butrint Foundation's archaeological excavations in Butrint to show the urban history of the place from the Bronze Age to the Ottoman period, the authors challenge the central theme of urban continuity and impact upon Mediterranean landscapes posited by Horden and Purcell, inThe Corrupting Sea(2000). Instead, the hinterland of Butrint, on the evidence of this and previous field surveys, appears to have had intense engagement with the town in the Early Roman period following the creation of the Roman colony. Significant engagement with Butrint continued in Late Antiquity, but subsequently in the Byzantine period, as before the creation of the colony, the relationship between the town and its hinterland was limited and has left a modest impact upon the archaeological record.


Author(s):  
V. Fedorov ◽  
T. Ippolitova ◽  
E. Sleptsov ◽  
K. Plemyashov

Purpose: Determination of the peculiarities of the behavior and the flow of childbirth in females (wrenches) of the northern home deer of the Even Breed of the Republic of Sakha (Yakutia), depending on the natural climatic zone of breeding.Material and research methods. Research of the reservation of the hotel's reservoir of the northern home deer was held from April to June in the reindeer herds of the mountain-taiga (FSUE «Yuchjuyuskoye») and the Tundrov zones (SHPZK «Taba-Yana») of the Republic of Sakha (Yakutia) in the conditions of nomadic home reindeer herding since 2013 2018 In the study, the method of observation is used with the registration of motor activity of animals and the activities of individual bodies in a certain living environment.Results. To fix some patterns and species features of the generic process, 8 main elementary behavioral reactions spent venizables of northern domestic deer per day before childbirth: walking, feeding feed, chewing, leisure standing, rest lying, sleep, urination (how many times / total time), defecation (how many times / total time). Also marked 4 behavioral reactions on the hotel day: the exploitation time of the fetus, the licking of the calf, the time of the calf on his feet after delivery, the first reception of the mosper calf after birth. For each parameter, data reflected in tabular format is obtained.Conclusion. It has been established that the degree of adaptation of the northern domestic deer to the harsh conditions of existence in various natural-climatic zones of the Republic of Sakha (Yakutia) is very high, which is manifested in a minor difference in the duration of the generic process and behavioral reactions at the vainer of the mountain and tundra and tundra dilution zones.


2018 ◽  
Vol 10 (4) ◽  
pp. 1159 ◽  
Author(s):  
Ilaria Zambon ◽  
Agostino Ferrara ◽  
Rosanna Salvia ◽  
Enrico Mosconi ◽  
Luigi Fici ◽  
...  

2008 ◽  
pp. 159-170 ◽  
Author(s):  
Sotirios Koussouris ◽  
George Gionis ◽  
Aikaterini Maria Sourouni ◽  
Dimitrios Askounis ◽  
Kostas Kalaboukas

2019 ◽  
Author(s):  
Myrto Tsiknia ◽  
Stilianos Fodelianakis ◽  
Nikolaos P. Nikolaidis ◽  
Nikolaos V. Paranychianakis

AbstractThere is a renewed interest in recent years on the ecological processes (stochastic vs selective) driving the assembly of microbial communities. Such information could potentially improve our understanding on ecosystem functioning and resilience to disturbances, ecosystem response to environmental shifts, and adoption of sustainable soil management practices. Herein, employing a suite of existing methodologies, we show that stochastic processes have an important role on the assembly of soil bacterial communities at a Mediterranean watershed. Moreover, we document that the relative contribution of assembly processes varies over the years. The observed intensification of stochastic processes was accompanied by a decrease in the contribution of variable selection in favor of homogeneous selection and dispersal and this trend was only marginally affected by land use (natural vs agricultural lands) or soil depth. Our study also revealed a high inter-annual turnover of soil microbial communities that was likely stimulated by the weak environmental selection and the prevailing environmental conditions (drying-wetting cycles) in Mediterranean landscapes, implying potential impacts on ecosystem functioning and our ability to predict soil response to environmental shifts. Using nitrogen mineralization rate (NMR) as a representative function we document highly variable NMR over the sampling years, land uses and soil depths and lack of significant associations with the monitored environmental variables and individual taxa. In summary, our study provides novel insights on the organization and functioning of microbial communities at Mediterranean ecosystems and sets directions towards a more advanced understanding of the relationships among environmental factors, microbial community structure, and ecosystem functioning that could contribute to sustainable management of these severely degraded ecosystems.


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