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1.
Glob Ecol Conserv ; 32: e01895, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34729384

RESUMO

Recent events related to the measures taken to control the spread of the Coronavirus (SARS-CoV-2) reduced human mobility (i.e. anthropause), potentially opening connectivity opportunities for wildlife populations. In the Italian Alps, brown bears have recovered after reintroduction within a complex anthropogenic matrix, but failed to establish a metapopulation due to reduced connectivity and human disturbance (i.e. infrastructure, land use, and human mobility). Previous work from Peters et al. (2015, Biol. Cons. 186, 123-133) predicted the main corridors and suitable hot spots for road network crossing for this population across all major roads and settlement zones, to link most suitable habitats. Bears used the identified hot spots for road network crossing over the years, but major barriers such as main motor roads were not overcome, possibly due to functional anthropogenic disturbance, specifically human mobility. By analyzing 404 bear occurrences reported to local authorities (as bear-related complaints) collected between 2016 and 2020 (March 9th - May 18th), hence including the COVID-19 related lockdown, we tested the effect of human presence on brown bears' use of space and hot spots for road network crossing. Animals occupied human-dominated spaces and approached hot spots for crossing at a higher rate during the lockdown than in previous years, suggesting that connectivity temporarily increased with reduced human mobility for this population. As a result of their increased use of hot spots, bears expanded their use of suitable areas beyond the population core area. Movement of animals across structural barriers such as roads and human settlements may therefore occur in absence of active disturbance. We also showed the value of predictive models to identify hot spots for animal barrier crossing, the knowledge of which is critical when implementing management solutions to enhance connectivity. Understanding the factors that influence immigration and emigration across metapopulations of large mammals, particularly carnivores that may compete indirectly with humans for space or directly as super-predators, is critical to ensure the long-term viability of conservation efforts for their persistence. We argue that dynamic factors such as human mobility may play a larger role than previously recognized.

2.
Methods Ecol Evol ; 12(6): 1093-1102, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34262682

RESUMO

Ecosystem heterogeneity has been widely recognized as a key ecological indicator of several ecological functions, diversity patterns and change, metapopulation dynamics, population connectivity or gene flow.In this paper, we present a new R package-rasterdiv-to calculate heterogeneity indices based on remotely sensed data. We also provide an ecological application at the landscape scale and demonstrate its power in revealing potentially hidden heterogeneity patterns.The rasterdiv package allows calculating multiple indices, robustly rooted in Information Theory, and based on reproducible open-source algorithms.

3.
PeerJ ; 7: e6394, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30740278

RESUMO

Bird migration is a widely studied phenomenon, however many factors that influence migratory flows remain unknown or poorly understood. Food availability en route is particularly important for many species and can affect their migration success, pattern and timing but this relationship has not been addressed at a wide scale due to the lack of spatial models of food availability on the terrain. This work presents a GIS-database approach that combines spatial and non-spatial ecological information in order to map fruit availability from vegetation over time in the SE Alps, an important node of European migratory routes. We created a unique database that contains information on the presence and periods of fructification of 52 wild plants carrying berries and a series of original cartographic themes. The presence and coverage of the plant species was modelled with the geo-statistical method of the Gaussian Kernel, which was validated against the ground truth of field sampling data with a correct classification power above 80% in most cases. The highest fruit availability in the study area during September and October co-occurs with the peak of captures of berry eating birds. The maps created and distributed along this work can be useful to address more detailed studies about stopover sites as well as the spatial ecology of other fruit eating animals.

4.
Sci Total Environ ; 579: 27-36, 2017 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-27876390

RESUMO

In recent decades, a dramatic landscape change has occurred in the European alpine region: open areas have been naturally recolonized by forests as traditional agricultural and forest activities were reduced and reorganized. Land use changes (LUC) are generally measured through GIS and photo interpretation techniques, but despite many studies focused on this phenomenon and its effects on biodiversity and on the environment in general, there is a lack of information about the transformation of the human-environment connection. The study of Traditional Ecological Knowledge (TEK), such as the ability to recognize wild plants used as medicine or food, can suggest how this connection evolved through time and generations. This work investigates the relationship between the natural forest cover expansion that influences the loss of open areas and the loss of TEK. Different data sources and approaches were used to address the topic in all its complexity: a mix of questionnaire investigations, historical maps, GIS techniques and modelling were used to analyse past land use changes and predict future scenarios. The study area, Trentino, Italy, is paradigmatic of the alpine situation, and the land use change in the region is well documented by different studies, which were reviewed and compared in this paper. Our findings suggest that open area loss can be used as a good proxy to highlight the present state and to produce future scenarios of Traditional Ecological Knowledge. This could increase awareness of the loss of TEK in other Alpine regions, where data on TEK are lacking, but where environmental trends are comparable.


Assuntos
Ecologia , Monitoramento Ambiental/métodos , Agricultura , Biodiversidade , Conservação dos Recursos Naturais , Ecossistema , Previsões , Florestas , Itália , Plantas
5.
Zookeys ; (208): 27-39, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22859870

RESUMO

In this paper we report about 88 longhorned beetles (Cerambycidae) species found in 6929 hectares and distributed along an altitudinal gradient of 1500 m of an Italian alpine valley (Val Genova, central-eastern Italian Alps). The species richness, result merging data from sixty years (1947-2007) of entomological surveys, corresponds to the 32% of the Italian cerambycid fauna confirming the high richness/surface ratio, probably unique in the Alps. The effect of thirteen environmental variables was tested on the species richness, but only the elevation resulted able to affect it. The species richness decrease with altitude not gradually, but experience a strong step above 1700 m a.s.l.. The highest species richness (average values of 42 species) was recorded at the lowest and mid elevations (between 800 and 1600 m a.s.l.). The species turnover along the altitudinal gradient is low suggesting moderate habitat turnover along the valley.One of the eighty-eight observed species, Tragosoma depsarium,is classified near threatened by the IUCN. Our data suggest that the wilderness of the valley close to the suitable management of grasslands and forests, help to support high level of cerambycids diversity. This biodiversity is good indicators of health of the wood saproxylic assemblages, as well an important food source for many vertebrate predators.

6.
Environ Manage ; 47(2): 263-78, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21190021

RESUMO

Park managers in alpine areas must deal with the increase in forest coverage that has been observed in most European mountain areas, where traditional farming and agricultural practices have been abandoned. The aim of this study is to develop a fine-scale model of a broad area to support the managers of Paneveggio Nature Park (Italy) in conservation planning by focusing on the fate of priority areas for conservation in the next 50-100 years. GIS analyses were performed to assess the afforestation dynamic over time using two historical maps (from 1859 and 1936) and a series of aerial photographs and ortho-photos (taken from 1954 to 2006) covering a time span of 150 years. The results show an increase in the forest surface area of about 35%. Additionally, the forest became progressively more compact and less fragmented, with a consequent loss of ecotones and open habitats that are important for biodiversity. Markov chain-cellular automata models were used to project future changes, evaluating the effects on a habitat scale. Simulations show that some habitats defined as priority by the EU Habitat Directive will be compromised by the forest expansion by 2050 and suffer a consistent loss by 2100. This protocol, applied to other areas, can be used for designing long-term management measures with a focus on habitats where conservation status is at risk.


Assuntos
Conservação dos Recursos Naturais/métodos , Cadeias de Markov , Ecossistema , Meio Ambiente , Agricultura Florestal/métodos , Sistemas de Informação Geográfica , Itália , Tecnologia de Sensoriamento Remoto , Árvores/crescimento & desenvolvimento
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