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211.
212.
Inês Catry Rita Alcazar Aldina M.A. Franco William J. Sutherland 《Biological conservation》2009,142(11):2782-2791
The recognition of the rapid and ongoing biodiversity loss has been leading to increasing conservation efforts. To maximise conservation success it is important to evaluate when interventions are likely to be effective. In Portugal, previous research identified that lack of suitable nest-sites was limiting the populations of the endangered lesser kestrel (Falco naumanni). Consequently, a massive provisioning of artificial nest-sites and the implementation of a medium term monitoring scheme was established. Our study showed that artificial nest-site provisioning is an effective measure in mitigating the lack of traditional sites. The lesser kestrel population increased from 155–158 pairs in 1996 to 527–552 in 2007, with 52% breeding in artificial nests. We investigate the factors affecting colony growth and found that colony growth was positively affected by the provisioning of artificial nests but negatively affected by predation rate and human disturbance. Between 2003 and 2007, mean colony growth was estimated at 6.46 ± 1.86 pairs for colonies where artificial nests were provided and −0.69 ± 0.5 pairs in colonies without nest-site provisioning. Moreover, predation rate was significantly lower in artificial nests than in natural ones and, although the number of competitor pairs in lesser kestrel colonies increased, the proportion of nests occupied by competitor species decreased. High risk of collapse and restoration of rural abandoned farmhouses may jeopardize the future of the lesser kestrel in Portugal. Nest-site provisioning and the establishment of a protection status for buildings holding colonies are likely the most effective means to guarantee the long-term survival of this species in the area. 相似文献
213.
Sandra Rosa Matias Marcela Cláudia Pagano Frederico Carvalho Muzzi Christiane A. Oliveira Andrea Almeida Carneiro Sá Nadja Horta Maria Rita Scotti 《European Journal of Soil Biology》2009,45(3):259-266
The iron-ore deposits in Minas Gerais state are concentrated in an area named Ferruginosous Quadrilateral, in which the dominant vegetation belongs to the Cerrado biome (savanna type, called campo rupestre or rupestrian field). This vegetation occurs in altitudes higher than 1000 m and is one of the most endangered biomes of the world. This study aimed to restore an area of rupestrian field used to keep iron-ore products, in which vegetation had been cut and thus resilience did not occur, worsening the low fertility of the fragile soil. Therefore, a revegetation model was proposed using two native species, Centrosema coriaceum (Leguminosae) and Tibouchina multiflora (Melastomataceae), inoculated with selected strains of arbuscular mycorrhizal fungi (AMF) and/or a rhizobium strain. After 48 months of plantation, the plant growth, survival index, physical and chemical soil properties, leaf nitrogen (N) and phosphorous (P), and P soil were evaluated. Inoculated plants benefited in all the analyzed aspects. While T. multiflora presented increased P content in leaves and soil rhizosphere only in inoculated plants, C. coriaceum showed the highest P content in both leaves and soil independently of inoculation. Although the inoculated plants presented more intense root colonization (AMF), the same mycorrhizal species were found in both inoculated and non-inoculated plants of C. coriaceum and T. multiflora. However, species of the Gigasporaceae family were favored in the C. coriaceum rhizosphere, as compared with T. multiflora. In addition, C. coriaceum was able to select in its rhizosphere a rhizobia strain efficient in P solubilization and a large and efficient population of phosphorus solubilizing microorganisms (PSM), preferentially composed of fungi. Through the similarity of their Internal Transcribed Spacer (ITS) sequences, the PSM fungi were identified as Fusarium oxysporum and Aspergillus fischeri using the BLAST database. The data presented suggest that C. coriaceum showed a strong rhizosphere effect in favor of a tripartite action of rhizobia, fungi and AMF populations as strategies to solubilize soil phosphate for survival and plant growth in the rupestrian field. Therefore, the inoculation of these microorganisms is desirable for mine recover. 相似文献
214.
Antonio Saracino Angelo Rita Sergio Rossi Laia Andreu-Hayles Gerhard Helle Luigi Todaro 《European Journal of Forest Research》2017,136(1):27-36
Developing long-term chronologies of tree-ring anatomical features to evaluate climatic relationships within species might serve as an annual proxy to explore and elucidate the climatic drivers affecting xylem differentiation. Pinus leucodermis response to climate was examined by analyzing vertical xylem resin ducts in wood growing at high elevation in the Apennines of peninsular Southern Italy. Early- and latewood tree-ring resin duct chronologies, spanning the 1804–2010 time period, were constructed. We analyzed the relationships between resin duct chronologies and climate over the last century using correlation and response function analyses. Overall, results showed that ring width and resin duct relationships differed between early- and latewood, which indicated conditions affecting growth were not associated with resin duct production. Results also revealed differential responses to climate between early- and latewood resin duct chronologies. A notable observation was a positive and stable relationship between latewood resin duct number chronology and July maximum temperature throughout the twentieth century. This result suggested resin ducts might be a suitable proxy to evaluate P. leucodermis response to climate in the study area. 相似文献
215.
Angelo Nolè Angelo Rita Agostino Maria Silvio Ferrara Marco Borghetti 《Annals of Forest Science》2018,75(3):83
Key message
A remote sensing-based approach was implemented to detect the effect of a late spring frost on beech forests in the Mediterranean mountain region. The analysis of spatio-temporal variability of frost effects on normalised difference vegetation index (NDVI) highlighted the distribution of the canopy damage across the forest according to geomorphic factors such as slope, aspect, and altitude.Context
Increased intensity and frequency of extreme temperatures such as late spring frosts and heat waves represent the main drivers affecting forest ecosystem structure and composition in the Mediterranean region.Aims
The main objective of this study was to evaluate the effects of a late spring frost disturbance, which occurred during spring 2016 in southern Italy, through the assessment of the spatial pattern of the damage to the beech forest canopy associated with the peak decrease in normalised difference vegetation index (NDVI), and the analysis of the NDVI temporal recovery after this frost disturbance.Methods
The forest areas affected by frost were detected through the NDVI differencing technique based on Landsat 8 (OLI/TIRS) imagery time series. The influence of local geomorphic factors (i.e., aspect, elevation, and slope) on forest NDVI patterns was assessed by means of a generalized additive model (GAM).Results
A rather counterintuitive NDVI patterns emerged according to the forest exposition, with NDVI significantly higher on the north facing areas than the southerly ones. The main canopy damage occurred at about 1250 m and reached up to 1500 m asl, representing the altitudinal range affected by the frost disturbance. Finally, the full canopy recovery occurred within 3 months of the frost event.Conclusion
The analysis of seasonal Landsat 8 image time series related to local geomorphic factors, such as aspect, slope, and altitude, and plant phenology on a frost event date, contributed to highlight the NDVI spatio-temporal variation and canopy recovery of a Mediterranean mountain beech forest.216.
Sanatombi Devi Yumkham Meena Elangbam Rita Nongmaithem Premita Devi Naorem Potsangbam Kumar Singh 《Genetic Resources and Crop Evolution》2018,65(4):1269-1280
The genus Adiantum L. (Pteridaceae–Vittarioideae) are medicinal ferns with around 200 species and distributed in temperate and tropical regions. Several species of the genus are used in traditional medicine in different parts of the world including the Chinese Herbal Medicine, United States Pharmacopoeia and Ayurveda System of Medicine and Homeopathy. In the present paper, an updated and comprehensive data on species diversity of Adiantum found in the seven (7) states of North East India will be discussed. Altogether, nine (9) species are recorded and this includes A. capillus–veneris L. with two (2) races, A. caudatum L., A. edgeworthii Hook., A. flabellulatum L., A. hispidulum Sw., A. incisum Forssk., A. peruvianum Klotzsch, A. philippense L. with three (3) subspecies and A. raddianum C. Presl. Brief morphological parameters, utilization including medicinal, economical and traditional aspects, along with their bioactive components are described. The paper also aims to provide for the first time an updated compilation of species information including correct nomenclature, synonyms, distribution and propagation. 相似文献
217.
218.
Isaac R Jacobson D Wanke C Hendricks K Knox TA Wilson IB 《Public health nutrition》2008,11(2):124-131
BACKGROUND: The effect of depression on dietary intake has not, to our knowledge, been examined in persons with HIV infection. METHODS: We conducted a longitudinal analysis of participants in the Nutrition for Healthy Living Study (NFHL). We measured changes in dietary macronutrient intake in participants who developed depression and, using multiple regression analysis, compared the changes with a control group of patients who did not become depressed. RESULTS: Ninety patients developed depression during the observation period, and we compared these with 152 non-depressed controls. The two groups had similar age and body mass index (BMI) at baseline, but those who developed depression were more likely to be female, less educated and had lower incomes. After adjustment, compared with non-depressed participants, those who developed depression had significantly greater decreases in the following daily intakes: total energy (-341 kcal, P = 0.006), protein (-12.3 g, P = 0.02), total fat (-18.5 g, P = 0.008), carbohydrate (-36.8 g, P = 0.02), total fibre (-4.3 g, P = 0.001) and saturated fat (-6.7 g, P = 0.01). There were no significant differences in the daily intakes of simple sugars and long-chain n-3 fatty acids, or BMI. CONCLUSION: Depression is associated with decreases in total daily energy intake and in six of the eight dietary components we measured. Clinicians should be aware that depression-associated nutritional deficiencies may complicate the care of persons with HIV. 相似文献
219.
220.
Yaacoub R Saliba R Nsouli B Khalaf G Birlouez-Aragon I 《Journal of agricultural and food chemistry》2008,56(16):7082-7090
The aim of the present study was to quantify some nutritional and safety quality parameter changes that take place in nuts (roasting) and sesame seeds (dehulling, roasting, milling, and sterilization) during processing. Such evaluation was based on chemical analysis of various indicators of lipid alteration in raw and processed pistachios, almonds, peanuts, and tahina. Lipid oxidation was assessed by the evolution of lipid oxidation products including hydroperoxides, p-anisidine, and thiobarbituric acid reactive substances, as well as carboxymethyllysine (CML) and trans fatty acids (tFAs). All these parameters were significantly affected by the different processing stages, especially by roasting and sterilization (tahina). Nut roasting and sesame heat treatment increased the primary (hydroperoxides) and secondary (aldehydic compounds) lipid oxidation products, with the p-anisidine value reaching 6-11.5 and thiobarbituric acid reactive substances 3-5 mg/kg (equiv of malondialdehyde) in the different end products. In addition, roasting led to the formation of CML (between 12.7 and 17.7 ng/mg) and tFAs (between 0.6 and 0.9 g/100 g) in nuts and tahina, which were absent in the raw material. Roasting parameters appear as the critical factor to control to limit the CML and tFA formation in the final product. 相似文献