1,720,990 research outputs found
Misura dei cambiamenti paesaggistici in ambiente alpino attraverso l’integrazione di dati telerilevati
Full text linkDalla metà del secolo scorso il paesaggio italiano ha subito delle profonde trasformazioni dovute al cambiamento di uso/copertura del suolo con la perdita di prati e pascoli a causa dei naturali processi di successione forestale, con forti ripercussioni sulla conservazione della biodiversità (Falcucci et al. 2006).
Gli ecosistemi alpini sono particolarmente sensibili a queste modifiche (Gehrig-Fasel et al. 2007) a causa dell’elevato grado di endemismi fortemente adattati (Billings 1974).
Per attuare delle misure di tipo conservazionistico, quindi è fondamentale quantificare il cambiamento di copertura del suolo avvenuto negli ultimi decenni ed impostare un monitoraggio a lungo termine delle strutture vegetali per individuare le aree maggiormente sensibili
Assessing the Alpine ibex and livestock distribution in Gran Paradiso National Park (GPNP)
No full textIn the last few decades a drastic decrease of GPNP ibex population, linked with a reduction of occupied territories, was occurred. This decline is partially related to recent climate changes but causes are still not completely clear. This work aims:
1) to analyse Alpine ibex (1985-2009) and livestock (2000-2009) distribution in GPNP;
2) to assess relation between distribution pattern and ibex population trend in 2000-2009.
The composition and spatial configuration of ibex and livestock occupied areas were described trough 5 landscape ecology metrics and tested using the Spearman’s rank correlation coefficient. The same statistical measure was also used to assess the relationship between distribution patterns and ibex population size. Results showed a reduction of ibex occupied territories from 4587,50 hectares in 1985 to 2331,25 ha in 2009 (r s = -0,818; P0,05). The relation between changes in ibex population trend and distribution patterns was not proven (all P>0,005). These results suggest that probably ibex distribution was influenced by different combined factors (landscape changes, climate change, and anthropic activities) and they show how landscape ecology approach may become a useful tool to understand the degree of fragmentation and connectivity of landscape, defined on species distribution
Patterns of spatio-temporal change in Alpine ibex (Capra ibex ibex, L.) distribution in Gran Paradiso National Park
Full text linkIbex is the symbolic species of mountain ungulates and currently it is classified at Least Concern by IUCN. In the last few decades there was a drastic decrease in population abundance linked with a reduction of stable occupied territories. Causes are still not completely clear but drastic decline is in partly due to recent climate changes. The objectives of this study are to analyse the ibex distribution changes in Gran Paradiso National Park (GPNP) in 1985-2014 period, the type of relation between pattern of distribution and population trend and finally the evidence of most used ibex ‘s territories in GPNP. To understand distribution patterns ibex census data are been analysed using metrics belonging to landscape ecology, an approach based on the notion that environmental patterns influence ecological processes. In particular 5 metrics are been used to assess the composition and spatial configuration of occupied areas, while distribution statistics provided a statistical summaries of obtained results. Results showed a reduction of ibex occupied territories from 4587.50 ha in 1985 to 2437.50 ha in 2014 and fragmentation of ibex occupied territories with a strong increase in number of occupied patches from 130 units to 229 units. We suggest that likely ibex distribution was influenced by different combined factors (landscape change, climate change, anthropic activities), which have to be still examined in depth. Landscape ecology approach may become an useful tool to understand the degree of fragmentation and connectivity of landscape defined on species distribution. The understanding of processes behind Alpine ungulates distribution have to consider the influence of landscape patterns on environmental processes to improve the conservation efforts at management level
A GIS-based assessment of land cover change in an Alpine protected areas
No full textThe European semi-natural landscape was markedly changed by the simultaneous effect of different processes.
In this context aerial photos are still a valuable means to detect this change delineating the fine-scale pattern over large areas. Furthermore this remote sensed data are available in decades where other remote sensed data were still not available.
Conversely data availability, software cost, image preparation and data mining affect the effective usability of this supports.
In this case study we used only free and open source geographical software (GFOSS) focusing on image preparation to improve data mining phase.
Aerial images of a mountainous protected area were orthorectified, smoothed and similar group of neighbouring pixels were grouped in meaningfull objects trough a semi-automatic unsupervised parameter optimization procedure. Pixel groups were manually labeleld creating a spatial explicit database.
Using a priori defined minimum mapping unit (MMU), the different landscape configurations were compared showing a change in protected area.
Implemented method ensured a strong repeatability and suitability over different aerial images and represented scene, but there are strong limitation in the use of this remote sensed data as data availability, an enormous amount of work for data pre-process and the need to easily automatize the classification step
Preliminary study on Alpine ibex (Capra ibex ibex, L.) and livestock distribution in Gran Paradiso National Park
Full text linkIn the last decades there was a drastic decrease in Gran Paradiso National Park ibex population linked
with a reduction of stable occupied territories. Causes are still not completely clear but drastic decline is in
partly related to recent climate changes. The objectives of this work are: (1) understand ibex distribution
in GPNP in 1985-2009 period and describe livestock distribution in the same area in 2000-2009; (2) assess
relation between distribution pattern and ibex population trend in 2000-2009. To understand distribution
patterns 5 landscape ecology metrics are been selected to assess the composition and spatial configuration
of occupied areas. Spearman’s rank correlation coefficient was used to test composition and configuration
metric trends and their relation with ibex population size. Results showed a reduction of ibex occupied
territories from 4,587.50 hectares in 1985 to 2,331.25 ha in 2009 (r
=-0,818; P<0,001). Number of patches
increased from 130 to 224 units (r
s
s
=0,784; P<0,001). Livestock distribution didn’t show a particular trend
(r
s
2
S), ammonia (NH
3
), carbon monoxide (CO), and carbon dioxide (CO
4
types of floating covers were tested: light expanded clay aggregate (leca), peat, sunflower oil, sawdust, straw,
and plastic film. The manure was stored at 5, 15, and 25 °C for 37 d. Gaseous emissions were measured from
headspaces of dynamic chambers. The results of our study showed that both the covering and temperature
have a noticeable impact on gas emission from pig liquid manure. The plastic film cover was the most
efficient at all temperatures tested, because it reduced the emissions of all measured gases. In this instance,
average emission reductions were: CH
4
91.5% (P<0.01), NO 92.0% (P<0.05), H
2
≈0 or P>0,05). The relation between changes in ibex population trend and distribution patterns was not
proven (all P>0,005). These results suggest that probably ibex distribution was influenced by different
combined factors (landscape changes, climate change, anthropic activities) and they show how landscape
ecology approach may become an useful tool to understand the degree of fragmentation and connectivity
of landscape defined on species distribution. In conclusion, the understanding of processes behind Alpine
ungulates distribution have to consider the influence of landscape patterns on environmental processes to
improve the conservation efforts at management level
The role of landscape changes in shaping Alpine species distribution
Full text linkEcosystems are deeply affected by the human activity and land use and land cover change is recognized as one of the most important causes of the alarming loss of biodiversity. In this scenario is fundamental to identify the most endangered areas where developing conservation purposes. The Alpine regions are of particular interest because they are characterized by rare and fragile ecosystems with a high level of endemism well adapted to harsh condition and particular sensitive to changes. Taking in account that the landscape is the result of natural and human processes is fundamental to reconstruct what happened in the past, describe the present through monitoring activities and try to predict the future events. Therefore in biodiversity conservation the remote sensing images are useful to define the landscape structure and to evaluate its changes. Considering the importance of the scale-dependency of ecological processes, we propose a multi-temporal and scale approach to describe the landscape structures and their role in shaping Alpine species distribution. The study area is the Gran Paradiso National Park, and we will focus both on test areas and both at the landscape scale. During the first step we will set a low-cost procedure of UAV (Unmanned Aerial Vehicle) survey adapted to Alpine environment in order to obtain high temporal and spatial resolution images in test areas. In the second step we will focus on the interpretation of the aerial images already available to reconstruct the land cover changes during the last decades and we compare the results with the UAV images. In the last step the analysis will be extended to entire Park landscape using satellite data. This multiscale analysis of landscape changes allow us to study how the environmental patterns affect the animal distribution using both a multi-taxa approach and considering a single target species. These results are essential for an adaptive management, balanced in space and time
Assessment of landscape change’s impact on Alpine species distribution using a multi-scale approach
Full text linkThere is a strong relation between biodiversity and traditional land use in Mediterrean areas. In these highly human dominated regions traditional acitvities profoundly shape the landscape with strong consequences on biodiversity pattern. However, in the last few decades the rapid socio-economic change lead to the abandonment of “marginal” land modifying the landscape structures. Available remote sensing data can provide information about environmental changes, but the occurrence of temporal and spatial gaps (e.g., the limited temporal archive of historical aerial images and the coarser spatial resolution of satellite data) can reduce the applicability of gained information. Considering the importance of the scale-dependency of ecological processes, we propose a multi-temporal and scale approach, combining remote sensed and field data, to monitor changes in vegetation and landscape structures and to evaluate their role in shaping Alpine species distribution. The study area is the Gran Paradiso National Park (NW Italian Alps) and we focused both on 5 altitudinal transects, representative of three altitudinal belts, and on landscape level. At first, from the interpretation of historical aerial photos in sampled areas, we reconstructed the land cover changes occurred during the last decades and we extended this information to the entire Park landscape, through a supervised classification of satellite data. Further, we developed a low-cost procedure of UAV (Unmanned Aerial Vehicle) survey adapted to Alpine environment, integrated with botanical sampling, in order to obtain highresolution land cover maps in test areas to replace the use of aerial photos in supervised classification of satellite data. This multi-scale analysis of landscape change allows us to detail how the environmental patterns affect the Alpine animal species distribution ranging from discrete areas to entire Park area
Targeted selective treatments : the alpine ibex (Capra ibex) as study model for small ruminants to identify the most affected and infectious individuals
No full textEffect of host life history on parasite infection : are old males the superspreaders?
Full text linkIdentification of the characteristics associated with the most infected individuals is a key topic in our understanding of parasite transmission. Host age and sex has been shown to be important, however their combined effect has rarely been investigated. We test the hypothesis that host sex and age of Ibex may interact to add further heterogeneity within host-parasite distributions.
Alpine ibex have a peculiar survival profile; males have high survival rates until the age of 11years, afterwards they show a drastic senescence, while females show a more constant and progressive survival decline. Such a pattern is interpreted as a life-history strategy where males allocate most of their energy to survival until reaching a definitive body size, which allows reproduction. Females optimize their fitness and modulate reproduction.
In this system we hypothesized sexes differs in their strategies to control infections along with age; males control parasites until 11years old at which point infections rise uncontrolled, whilst females constantly control infections. As such, the old male individuals will be the most infected and so potentially super-spreaders of infection.
We tested this hypothesis analysing abomasal parasites and modelling different age effects.
The model best describing our data confirmed our hypothesis identifying the highest infections and infectiousness in old males whilst females were more constant by comparison
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