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Agroforestry has been suggested to produce an array of ecological and socio-economic benefits that not only reach their adopters, but society as a whole. In spite of strong evidence of the benefits of agroforestry, there is a lack of understanding of the public perceptions of those benefits, which prevents the development of benefit-based promotion strategies of agroforestry products. Thus, this study examines the awareness of these benefits among residents and explores whether perceptions vary across individuals with different socio-demographic characteristics. An on-line platform was used to survey three panels of residents from Missouri, Pennsylvania and Texas. Overall, respondents had a neutral perception of the importance of the ecological and socio-economic benefits that agroforestry farms provide to society when compared to farms employing conventional agricultural practices. These results stress the need to increase public awareness of agroforestry practices and their benefits to more strategically position their products among the final consumer. Gender, education level, and residence location were significantly associated with the perceived ecological benefits produced by agroforestry farms and to a lesser extent with the socio-economic benefits. Results also showed that females and young individuals have a greater awareness of several benefits produced by agroforestry farms. Critical marketing implications to stimulate the purchase of agroforestry products (e.g., berries, nuts) among specific groups of consumers are discussed. 相似文献
3.
Caboni P Cabras M Angioni A Russo M Cabras P 《Journal of agricultural and food chemistry》2002,50(12):3491-3494
In this work an HPLC method for the determination of azadirachtin residues on olives was developed, and the field degradation kinetics of the pesticide was studied. In field trials the active ingredient (a.i.) decay had a half-life time of 0.8 days, which was too short to show a good efficacy of treatment. The mechanism of disappearance of the pesticide studied with model systems showed that it was unrelated to evaporation, thermodegradation, and co-distillation, but it was related to photodegradation. The high photodegradation rate of commercial formulations calls for the need to test different formulates in order to increase the persistence of the residue and thus the pesticide's efficacy. 相似文献
4.
Giordani Gianmarco Roberta Azzoni Marco Bartoli Pierluigi Viaroli 《Water, air, and soil pollution》1997,99(1-4):363-371
The aim of this work was to analyse factors which regulate sulphide mobility in the sediments of a dystrophic lagoon (Sacca di Goro, the southern lagoon of the Po river delta, Italy). In 1995-96, sediment oxygen demand and variations in organic matter content, redox potential, iron availability, inorganic sulphur concentrations and sulphate reduction rates were measured in sediment profiles at three stations (G, 4 and 17) representative of the main areas of the lagoon. Stations differed mainly in their salinity range and primary producer communities. High concentrations of reactive iron (110-275 µmol ml-1) and low sulphate reduction rates (0.8-16.1 mmol m-2 d-1) were measured in the sediment. Moreover, high concentrations of reactive ferric iron were detected in winter and spring at the stations closest to the freshwater inputs. Nevertheless, in summer, high concentrations of free sulphides were detected in the porewater, although most of the reactive ferrous iron was not sulphide-bound, indicating that not all of the reactive iron pool was available to buffer against sulphide release and thus measures of reactive iron pools may not be a good measure of the true buffering capacity of the sediment. Furthermore, a considerable production of sulphide may occur in the decaying Ulva biomass in the water column, where its concentration will be independent of the potential buffering capacity of iron in the sediment. Therefore when assessing the vulnerability of coastal lagoons to dystrophic events, both the size and availability of the reactive iron pool as well as the site of sulphide production must be taken into consideration. 相似文献
5.
Chericoni S Prieto JM Iacopini P Cioni P Morelli I 《Journal of agricultural and food chemistry》2005,53(12):4762-4765
The essential oil obtained from the bark of Cinnamomum zeylanicum Blume (Lauraceae) and three of its main components, eugenol, (E)-cinnamaldehyde, and linalool (representing 82.5% of the total composition), were tested in two in vitro models of peroxynitrite-induced nitration and lipid peroxidation. The essential oil and eugenol showed very powerful activities, decreasing 3-nitrotyrosine formation with IC50 values of 18.4 microg/mL and 46.7 microM, respectively (reference compound, ascorbic acid, 71.3 microg/mL and 405.0 microM) and also inhibiting the peroxynitrite-induced lipid peroxidation showing an IC50 of 2.0 microg/mL and 13.1 microM, respectively, against 59.0 microg/mL (235.5 microM) of the reference compound Trolox. On the contrary, (E)-cinnamaldehyde and linalool were completely inactive. 相似文献
6.
Keller HU Jorda L Küppers M Gutierrez PJ Hviid SF Knollenberg J Lara LM Sierks H Barbieri C Lamy P Rickman H Rodrigo R 《Science (New York, N.Y.)》2005,310(5746):281-283
The OSIRIS cameras (optical, spectroscopic, and infrared remote imaging system) onboard the European Space Agency's Rosetta spacecraft observed comet 9P/Tempel 1 for 17 days continuously around the time of NASA's Deep Impact mission. The cyanide-to-water production ratio was slightly enhanced in the impact cloud, compared with that of normal comet activity. Dust particles were flowing outward in the coma at >160 meters per second, accelerated by the gas. The slope of the brightness increase showed a dip about 200 seconds after the impact. Dust Afrho values before and long after the impact confirm the slight decrease of cometary activity. The dust-to-water mass ratio was much larger than 1. 相似文献
7.
Proline and light as quality enhancers of rocket (Eruca sativa Miller) grown under saline conditions
Giancarlo Barbieri Antonella BottinoEmilio Di Stasio Simona ValloneAlbino Maggio 《Scientia Horticulturae》2011
Stress conditions experienced during growth may affect plant responses during post-harvest storage and eventually determine the overall quality of commercial products. In this context, we hypothesized that foliar applications of proline during the growth cycle and light exposure during post-harvest storage could be two important modulators of yield and quality parameters of rocket plants exposed to NaCl stress. Dry matter percentage increased upon NaCl treatment. However, fresh weight loss during storage did not change over time as a consequence of salt stress. High salinity (100 mM NaCl) moderately reduced both leaf nitrate (14%) and nitrite (3%) contents. Lipophilic (LAC) and hydrophilic (HAC) antioxidant activities also decreased by 10% at the highest salinization (average of two growth cycles). In contrast, during storage, LAC decreased whereas HAC increased. Proline applications reduced the leaf nitrate content during storage by 16%, increased carotenoids and chlorophyll contents in salinized plants and also increased the ascorbate leaf concentration in both salinized and non-salinzed plants. Light storage enhanced fresh weight loss in contrast to dark storage. However the exposure to light reduced leaf nitrate levels by 7% (average of two growth cycles) and contributed to maintain high leaf ascorbate concentrations over time. 相似文献
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9.
The insecticide cartap is the bis(thiocarbamate) derivative of 2-(dimethylamino)propane-1,3-dithiol, which on oxidation forms the natural toxicant nereistoxin (NTX) [4-(dimethylamino)-1,2-dithiolane]. Both cartap and NTX are ion channel blockers of the nicotinic acetylcholine receptor (nAChR). Cartap was originally proposed to act only after metabolic conversion to NTX and later suggested to block directly without activation. The present study uses a new approach to differentiate these hypotheses, that is, pH effects on channel-blocking activity and hydrolysis rates. As controls, mecamylamine (the classic channel blocker) and NTX are stable and similar in channel-blocking potency ([(3)H]thienylcyclohexylpiperidine binding assay, honeybee nAChR) at pH 6.1-8.4. In contrast, cartap is >200-fold more effective at pH 7.4 than at pH 6.1, indicating that it undergoes hydrolytic activation. Cartap slowly hydrolyzes to cartap monothiol at pH 6.1 but quickly forms the dithiol and some NTX at pH 7.4. The relationship between potency and hydrolysis products at various pH ranges suggests that cartap dithiol is the most plausible blocking agent. 相似文献
10.
Vincenzo Montesano Donatella Negro Giulio Sarli Giuseppina Logozzo Pierluigi Spagnoletti Zeuli 《Genetic Resources and Crop Evolution》2012,59(5):701-716
A collecting expedition has been carried out in the inland areas of the Basilicata Region, South Italy. Each of the 14 selected municipalities was subdivided in three strata based on the geographical distribution of population and orography: 1. city boundaries, 2. group of country houses, 3. isolated farm houses. Five sites were selected within each stratum/town for a total of 185 sites. In 101 sites crop species germplasm was collected and the farmer-maintainers were interviewed. Altogether 350 accessions were collected, the most common species were Capsicum annuum, Lycopersicon esculentum and Phaseolus vulgaris. A significant number of landraces are still preserved on farm, mostly in isolated farm houses (average age of farmers: 60?years) adopting traditional farming systems but a number of young farmers were also present. Perspectives for on farm conservation and management are discussed and public economic support for “farmer-maintainers” proposed. 相似文献