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501.
Giulia Cutuli Stefano Cannicci Marco Vannini Sara Fratini 《Behavioral ecology and sociobiology》2013,67(2):273-281
Sperm storage is widespread in many vertebrate groups, and it is frequently associated with promiscuous mating systems. Chelonian species are one of the most outstanding examples of a promiscuous group capable of long-term sperm storage; specialized structures have evolved within the oviducts of these vertebrates to ensure sperm vitality across reproductive cycles. Thus far, few studies have investigated the factors regulating multiple paternity, sperm usage by females and paternity distribution in successive clutches. This study aimed to investigate the effect of mating order on male mounting and reproductive success in Testudo hermanni hermanni, combining behavioural and genetic data. A series of planned matings were performed, within which experimental females were mated sequentially to two different males under controlled conditions. Observations conducted during experimental matings revealed that courtship displays did not significantly differ between the first and second males to mate with a female. Interactions ending with a mount were characterized by a significantly higher intensity and occurrence of determinate courtship behaviours, for example biting and running after the female. Paternity analysis performed on hatchlings produced from experimental females revealed that 46 % of the clutches were multi-sired. A significant contribution of previous years' partners was still found, thus confirming the long-term sperm storage within the female oviduct in this species. Finally, mating order did not significantly affect the reproductive success of experimental males during the on-going reproductive season. 相似文献
502.
503.
SUMMARY Studying the interactions among ecological factors and economic performance measured at the local scale is necessary to suggest policies able to mitigate natural resource depletion in complex ecosystems, like those in the Mediterranean region. The aim of this paper is to explore the relationship among natural resource depletion due to land degradation (LD) and some economic characteristics of local labour systems in Italy, a country where many areas, especially southern regions, are vulnerable. LD was estimated using an environmental sensitive area index, covering the national territory at a fine scale, which takes into account ecological factors such as climate, soil and vegetation. Economic indicators used here consider per capita income, land productivity, production and labour productivity by sector (agriculture, industry and services). A regression analysis was built-up at the LLS scale using an index change over time (1990–2000) as dependent variable and economic variables as predictors. A principal component analysis (PCA) was carried out to synthesise the outputs of the regression analysis. Results indicate a negative relationship among per capita income and LD over the whole study area. However, other variables showed a significant correlation with the dependent variable, highlighting the importance of local factors to increase land vulnerability. In order to clarify the contribution of economic factors to natural resource depletion it is necessary to drive integrate policies to combat LD in dry Mediterranean areas. 相似文献
504.
Marco Ferretti Emilia Barbolani Paolo Grossoni Romano Gellini Francesco Pantani 《Chemistry and Ecology》1993,8(1):1-10
One year old needles of both healthy and damaged silver fir and Norway spruce from the area of Trento (Northern Italy) were observed by SEM. Needles of damaged trees show quite evident structural alterations of epidermis, expecially epicuticular waxes. Roots and needles of both fir and spruce are also tested for their metal content. Evidence is reported of an increasing concentration of Fe, Mg and Ca in roots of plants grown on alkali soil. Ca, and to a lesser extent Fe, Al and Pb, appears to be more present in old needles, whereas K and Mg exhibit higher amounts in young needles. Some indications are found between damage and the content of some metals such as Mg and Mn in needles. 相似文献
505.
Matteo Vizzarri Ugo Chiavetta Giovanni Santopuoli Daniela Tonti Marco Marchetti 《Journal of Environmental Planning and Management》2015,58(8):1454-1478
In last decades, numerous efforts have been carried out by the scientific community to assess the multifunctional role of forests in supporting the forest decision-making processes. Recently developed in Italy, the Forest Landscape Management Planning seems to be the most suitable tool to maintain the sustainability balance between forests and local populations. This research identifies and maps different forest ecosystem functions in a mountain Natura2000 Network site by performing a spatial estimation of forest inventory parameters, and implementing a multi-criteria and multi-level approach. Final results on mapping of forest functions show acceptable values of classification accuracy. 相似文献
506.
Marco A. López-Mata Saúl Ruiz-Cruz José de Jesús Ornelas-Paz Carmen Lizette Del Toro-Sánchez Enrique Márquez-Ríos Norma P. Silva-Beltrán Luis A. Cira-Chávez Silvia E. Burruel-Ibarra 《Journal of Polymers and the Environment》2018,26(2):452-461
Chitosan films (CF) [1 and 2% w/v] alone and with cinnamaldehyde (CNE) [0.25, 0.5 and 1% v/v] were prepared using an emulsion method, and the obtained films were characterized in terms of water vapor permeability (WVP), water solubility and optical, mechanical and antioxidant properties. The incorporation of CNE at 1% (v/v) significantly decreased the water solubility of the film by approximately 4% for the 1 and 2% CF films, whereas the WVP increased (2.5–3.5 times). The incorporation of CNE (0.25 and 0.5%) into 2% CF significantly increased the tensile strength (TS) (62 and 34%, respectively) and the percent elongation (%E) values, 26, 30 and 52% for CF that contained 0.25, 0.5 and 1% CNE, respectively. The largest value of the elasticity modulus (EM) was observed for 2% CF with 0.25% CNE. All films exhibited a yellow appearance (b*), but the CNE content had a marked impact on the coloration of the films. The CNE recoveries of the CF films (1 and 2%) with 1% of CNE were high (43 and 67%). The antioxidant activities indicated that the incorporation of 1% CNE into CF films (1 and 2%) increased the antioxidant activity. The protective effects of the films with and without CNE on erythrocytes were very strong (36–72% hemolysis inhibition). These results suggest there are potential applications for CF-CNE films as active packaging for the preservation of food products. 相似文献
507.
Jaime David Pérez-Martínez Mayra Sánchez-Becerril José de Jesús Ornelas-Paz Marco M. González-Chávez Vrani Ibarra-Junquera Pilar Escalante-Minakata 《Journal of Polymers and the Environment》2013,21(4):1040-1051
Pectin from the cladode flour of Opuntia ficus indica was extracted at different ethylenediaminetetraacetate concentrations (10 or 20 %), temperatures (40 or 80 °C), pH values (2 or 11), and times (10, 20, 30 40, 50 or 60 min). The effects of the extraction conditions on the yield, purity, and chemical composition of pectin were assessed. The highest pectin yield was observed for pectin obtained under alkaline conditions and 20 % of EDTA. However, pectin produced from alkaline extractions had a lower content of GalA than pectin produced from acid extractions. Higher temperatures favored the extraction of pectin under acid conditions, but these conditions diminished the arabinose content of pectins in a time-dependent manner. The tested extraction conditions caused only slight changes in the molecular weight of the extracted pectin as a function of time. 相似文献
508.
A. Adrados I. De Marco A. Lopez-Urionabarrenechea B.M. Caballero M.F. Laresgoiti 《Waste management (New York, N.Y.)》2013,33(1):52-59
In this paper rejected streams coming from a waste packaging material recovery facility have been characterized and separated into families of products of similar nature in order to determine the influence of different types of ingredients in the products obtained in the pyrolysis process. The pyrolysis experiments have been carried out in a non-stirred batch 3.5 dm3 reactor, swept with 1 L min?1 N2, at 500 °C for 30 min. Pyrolysis liquids are composed of an organic phase and an aqueous phase. The aqueous phase is greater as higher is the cellulosic material content in the sample. The organic phase contains valuable chemicals as styrene, ethylbenzene and toluene, and has high heating value (HHV) (33–40 MJ kg?1). Therefore they could be used as alternative fuels for heat and power generation and as a source of valuable chemicals. Pyrolysis gases are mainly composed of hydrocarbons but contain high amounts of CO and CO2; their HHV is in the range of 18–46 MJ kg?1. The amount of COCO2 increases, and consequently HHV decreases as higher is the cellulosic content of the waste. Pyrolysis solids are mainly composed of inorganics and char formed in the process. The cellulosic materials lower the quality of the pyrolysis liquids and gases, and increase the production of char. 相似文献
509.
510.
European winegrowers’ perceptions of climate change impact and options for adaptation 总被引:2,自引:0,他引:2
Antonella Battaglini Gerard Barbeau Marco Bindi Franz-W. Badeck 《Regional Environmental Change》2009,9(2):61-73
A questionnaire on the perception of climate change and the impact of climate change was distributed among winegrowers in France, Germany, and Italy. These countries are located in three macro-climatic regions that experienced different patterns of climatic change in the twentieth century—Atlantic, transition to Continental and Mediterranean. The majority of winegrowers perceived changing climatic conditions in the last few decades. The characterization of these changes is consistent with results obtained by the analysis of long-term trends in climatic records. The winegrowers noted impacts on harvestable quantities (mainly in Italy), must quality, and risks of pests and diseases. The majority of respondents (66%) indicated an impact on wine quality, which was perceived as quality improvement in 55% of the cases. Perceived impacts on pests and diseases were reported in 56% of the responses. A strong majority of this group (80%) also reported increasing threats. Perceived climatic change and its noticeable impacts has led to growing interest in adaptation options, combined with a need for more information, among winegrowers. Thus, the transfer of technical knowledge from scientific research to practice is necessary for adaptation. Plans for adaptation by a change of wine varieties were reported with substantially different results among the regions. A majority of German growers said they would consider changing varieties to adapt to warming temperatures, while only a minority of the Italian and French growers said they would consider such changes. However, readiness to adopt adaptation measures is correlated with the degree of changes already planned, independent of climatic change. 相似文献