583 research outputs found

    Indicators of biodiversity in an intensively cultivated and heavily human modified landscape

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    Nowadays, the loss of biodiversity in agroecosystems due to the intensification of farming practices is happening very fast, and therefore, stopping or slowing it down should be a priority for conservation. To detect changes in these environmental contexts, one approach contemplates focusing on a limited set of indicator species that can alert us to ongoing changes in progress. In this research, we aimed to measure the biodiversity of vertebrates using a multi-taxa approach in an intensively cultivated and highly inhabited area located in northern Italy. We investigated the relationships between biodiversity and environmental characteristics and we identified the taxonomic groups that can be used as indicators of biodiversity. Data collection was carried out in 2016 with different methods depending on the taxonomic group, in 131 sampling units chosen using a Tessellation Stratified Sampling. Then we calculated for each sampling unit a standardized Biodiversity Index, which was related to environmental variables concerning the land use and the landscape configuration using Multiple Linear Regression Analysis and Information-Theoretic approach. We used correlation analyses and the Indicator Species Analysis (IndVal) to identify the taxonomic groups and species that can be used as indicators of biodiversity. Biodiversity was positively related to the number of patches of natural vegetation, whereas it was negatively affected by the number of patches of artificial surfaces and by habitat diversity. Our findings agree with those obtained by many other researchers, which pointed out that agroecosystems provide adequate shelters, suitable foraging habitats and nesting sites. The negative effect of habitat diversity was explained by the area-heterogeneity trade-off. Therefore, sites with high heterogeneity will not contain enough cover of residual natural vegetation, essential to maintain high biodiversity, because increasing compositional heterogeneity within a fixed area simultaneously reduces the surface of each cover type. The analyses showed that birds and reptiles might be used as biodiversity indicators of vertebrates. Eurasian Magpie and Green Whip Snake, both generalist species, were associated with sites of low biodiversity, whereas seven birds, both generalists and farmland specialists, were associated with sites of medium biodiversity. In high biodiversity sites there were not indicator species. To conclude, in less natural environments, such as urban and agricultural landscapes, a combination of specialist and generalist indicator species seems adequate to monitor biodiversity changes. Our findings increase the knowledge of these very dynamic ecosystems, being important both to plan strategies for biodiversity conservation and to guarantee ecosystems services useful for humans

    Demographic parameters of reintroduced grey partridges in central Italy and the effect of weather

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    International audienceGrey partridge populations declined in Europe from mid-1950s onwards mostly due to modifications of agricultural cropping. In Italy, the decline was even more dramatic because of over-hunting and restocking with allochthonous birds. We carried out a research on a re-introduced population in Central Italy from 1995 to 2005, with the aim of evaluating the reintroduction success and separating the intrinsic and external factors influencing year-to-year changes in partridge density with particular respect to the weather. Average spring density was 4.5 pairs per square kilometre (SD = 1.52); our population reached a peak few years after the reintroduction and then declined. Brood production rate was close to that of declining European populations (average 33.9%; SD = 10.21), and chick survival rate (average 40%; = 17.61) determined the change of breeding abundance from year to year + 1. Our population seemed to be mainly affected by brood production and chick survival rates and by the weather; in particular, higher early winter and spring temperatures increased breeding density whilst higher early summer temperatures decreased brood production rate

    Spring diet of the pine marten in Sardinia, Italy

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    Alimentación primaveral de la marta en Cerdeña, ItaliaEl conocimiento del comportamiento de alimentación de un carnívoro es esencial para entender su ecología. La marta Martes martes se define comúnmente como un depredador generalista oportunista, porque su dieta en Europa incluye mamíferos, frutas, aves y invertebrados. A partir del análisis de las heces, hemos descrito los hábitos alimenticios en primavera y la amplitud del nicho trófico de la marta en ambiente mediterráneo en Cerdeña (Italia central). Los pequeños mamíferos (sobre todo Apodemus sylvaticus, Mus musculus y Eliomys quercinus) representan la fuente más importante de alimentación de la marta, ya que constituyen aproximadamente el 52% del volumen medio. Otra fuente importante de alimentos secundarios la constituyen los invertebrados (especialmente escarabajos y larvas de insectos) y las aves (paseriformes casi exclusivamente), mientras que los grandes mamíferos, los lagomorfos, los reptiles y las frutas están poco representados en la dieta. La composición de la dieta y el valor del índice de Levins indican que la marta en Cerdeña es un depredador especialista facultativo, con una especialización en la depredación de los micromamíferos.Knowledge of a carnivore’s foraging behaviour is essential to understand its ecology. The pine marten Martes martes is commonly defined as an opportunistic generalist predator since its diet in Europe includes mammals, fruits, birds and invertebrates. Based on faecal analyses, we evaluated spring feeding habits and trophic niche breadth of the pine marten in a Mediterranean landscape on the island of Sardinia (Central Italy). The most important source of food for the pine marten was small mammals (mainly Apodemus sylvaticus, Mus musculus and Eliomys quercinus), accounting for 52% of the percent mean volume. Important secondary foods were invertebrates (mainly beetles and insect larvae) and birds (almost exclusively passerines), whereas large mammals, lagomorphs, reptiles and fruits made little contribution to the diet. The diet composition and the Levins’ index value suggest that the pine marten in Sardinia behaves as a facultative specialist predator, with a specialization towards small mammals.Alimentación primaveral de la marta en Cerdeña, ItaliaEl conocimiento del comportamiento de alimentación de un carnívoro es esencial para entender su ecología. La marta Martes martes se define comúnmente como un depredador generalista oportunista, porque su dieta en Europa incluye mamíferos, frutas, aves y invertebrados. A partir del análisis de las heces, hemos descrito los hábitos alimenticios en primavera y la amplitud del nicho trófico de la marta en ambiente mediterráneo en Cerdeña (Italia central). Los pequeños mamíferos (sobre todo Apodemus sylvaticus, Mus musculus y Eliomys quercinus) representan la fuente más importante de alimentación de la marta, ya que constituyen aproximadamente el 52% del volumen medio. Otra fuente importante de alimentos secundarios la constituyen los invertebrados (especialmente escarabajos y larvas de insectos) y las aves (paseriformes casi exclusivamente), mientras que los grandes mamíferos, los lagomorfos, los reptiles y las frutas están poco representados en la dieta. La composición de la dieta y el valor del índice de Levins indican que la marta en Cerdeña es un depredador especialista facultativo, con una especialización en la depredación de los micromamíferos

    Iodine uptake and distribution in horticultural and fruit tree species.

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    Iodine is an essential microelement for humans and iodine deficiency disorder (IDD) is one of the most widespread nutrient-deficiency diseases in the world. Iodine biofortification of plants provides an attractive opportunity to increase iodine intake in humans and to prevent and control IDD. This study was conducted to investigate the iodine uptake and accumulation in edible portion of two fruit trees: plum and nectarine, and two horticultural crops: tomato and potato. Two type of iodine treatments (soil and foliar spray application), and, for fresh market tomato, two production systems (open field and greenhouse hydroponic culture) were tested. The distribution of iodine in potato stem and leaves, and in plum tree fruits, leaves, and branches was investigated. Iodine content of potato tubers after postharvest storage and processing (cooking), and iodine content of nectarine fruits after postharvest storage and processing (peeling) were also determined. Differences in iodine accumulation were observed among the four crops, between applications, and between production systems. In open field, the maximum iodine content ranged from 9.5 and 14.3 \u3bcg 100 g 121 for plum and nectarine fruit, to 89.4 and 144.0 \u3bcg 100 g 121 for potato tuber and tomato fruit, respectively. These results showed that nectarine and plum tree accumulated significantly lower amounts of iodine in their edible tissues, in comparison with potato and tomato. The experiments also indicated hydroponic culture as the most efficient system for iodine uptake in tomato, since its fresh fruits accumulated up to 2423 \u3bcg 100 g 121 of iodine. Iodine was stored mainly in the leaves, in all species investigated. Only a small portion of iodine was moved to plum tree branches and fruits, and to potato stems and tubers. No differences in iodine content after fruit peeling was observed. A significant increase in iodine content of potato was observed after baking, whereas a significant decrease was observed after boiling. We concluded that iodine biofortified fresh market tomato salad, both from field and hydroponics cultivation, and baked potatoes can be considered as potential functional foods for IDD prevention

    Allergic sensitization to common pets (cats/dogs) according to different possible modalities of exposure: an Italian Multicenter Study

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    Background: The query "are there animals at home?" is usually administered for collecting information on anamnesis. This modality to consider exposure to pet allergens constitutes a potential bias in epidemiological studies and in clinical practice. The aim of our study was to evaluate/quantify different modalities of exposure to cat/dog in inducing allergic sensitization. Methods: Thirty Italian Allergy units participated in this study. Each centre was required to collect the data of at least 20 consecutive outpatients sensitized to cat/dog allergens. A standardized form reported all demographic data and a particular attention was paid in relieving possible modalities of exposure to cat/dog. Results: A total 723 patients sensitized to cat/dog were recorded, 359 (49.65%) reported direct pet contact, 213 patients (29.46%) were pet owners, and 146 subjects (20.19%) were exposed to pets in other settings. Other patients were sensitized by previous pet ownership (150-20.75%) or indirect contact (103-14.25%), in 111 subjects (15.35%) any contact was reported. Conclusions: Only 213 patients (29.46%) would be classified as "exposed to animals" and 510 (70.54%) as "not exposed" according to usual query. Our classification has shown that many "not-exposed" subjects (399-55.19%) were "really exposed". The magnitude of exposure to pet allergens at home is not related exclusively to pet ownership. These considerations should be taken into account during the planning of epidemiological studies and in clinical practice for the management of pet allergic individuals
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