1,720,970 research outputs found
Potential herbicidal effect of oregano, rosemary and rue on some mediterranean weed species
No full textWhat drives organic food consumption in Lebanon?
No full textTo increase the sparse knowledge about what drives organic food consumers in developing markets, Lebanese consumers' reasons and motives for buying organic food are studied in the framework of means-end chain theory. A sample of N = 180 Lebanese consumers was interviewed in several retail outlets using a hard laddering questionnaire. The data were subjected to frequency analysis, cluster analysis, and structural equation modelling. Hierarchal value maps constructed from the laddering interviews revealed that “quality of life,” “pleasure,” and “peace of mind” are the main values driving organic food consumption in Lebanon. Frequent organic consumers displayed higher concern for their family's health and for the environment, whereas occasional organic consumers cared more about their own pleasure and were more likely to perceive organic food as a traditional and nostalgic product. Structural equation modelling revealed that “care for nature” and “care for children's health” significantly affect consumers' (self-reported) purchasing behaviour. The found means-end chains are a useful basis for marketing campaigns for organic food products in the Lebanese market. One focus of marketing campaigns should be raising consumers' awareness on the environmental benefits of organic production and the fact that it does not allow the use of harmful chemical products
Chemical composition and in vitro activity of plant extracts from Ferula communis and Dittrichia viscosa against postharvest fungi
No full textF. communis and D. viscosa are perennial Mediterranean weeds that have been used for different therapeutic purposes in traditional pharmacopeia. Plant extracts were obtained from air dried D. viscosa young shoots (DvA) and F. communis aerial part (FcA) and roots (FcR) with n-hexane. The chemical compositions of the extracts were analyzed by HPLC-DAD, LC-MS (ESI) and LC-Q-TOF techniques. Two sesquiterpene lactones (inuviscolide, tomentosin) and three sesquiterpene acids (costic acid, hydroxycostic acid, ilicic acid) were identified from the D. viscosa extract, while in F. communis extracts three daucane sesquiterpenes (acetoxyferutinin, oxojaeskeanadioyl anisate, fertidin) and one coumarin (ferulenol) derivates were found. Biological activities of plant extracts were studied in in vitro experiments on the colonies and conidia of Botryotinia fuckeliana, Penicillium digitatum, P. expansum, Monilinia laxa, M. fructigena and Aspergillus spp. Extracts showed varying degree of antifungal activities on colony growth and conidia germination. The extract from FcA showed the least effect, while DvA extract had the strongest fungitoxic effects. FcR extract presented a fungitoxic effect on the colony growth, but it was not able to inhibit the conidia germination. These distinctions can be attributed to the differences in chemical composition of plant extracts
Organic vs. organic - soil arthropods as bioindicators of ecological sustainability in greenhouse system experiment under Mediterranean conditions
Full text linkOrganic greenhouse (OGH) production is characterized by different systems and agricultural practices with diverse environmental impact. Soil arthropods are widely used as bioindicators of ecological sustainability in open field studies, while there is a lack of research on organic production for protected systems. This study assessed the soil arthropod abundance and diversity over a 2-year crop rotation in three systems of OGH production in the Mediterranean. The systems under assessment differed in soil fertility management: SUBST - a simplified system of organic production, based on an input substitution approach (use of guano and organic liquid fertilizers), AGROCOM - soil fertility mainly based on compost application and agroecological services crops (ASC) cultivation (tailored use of cover crops) as part of crop rotation, and AGROMAN - animal manure and ASC cultivation as part of crop rotation. Monitoring of soil fauna was performed by using pitfall traps and seven taxa were considered: Carabidae, Staphylinidae, Araneae, Opiliones, Isopoda, Myriapoda, and Collembola. Results demonstrated high potential of ASC cultivation as a technique for beneficial soil arthropod conservation in OGH conditions. SUBST system was dominated by Collembola in all crops, while AGROMAN and AGROCOM had more balanced relative abundance of Isopoda, Staphylinidae, and Aranea. Opiliones and Myriapoda were more affected by season, while Carabidae were poorly represented in the whole monitoring period. Despite the fact that all three production systems are in accordance with the European Union regulation on organic farming, findings of this study displayed significant differences among them and confirmed the suitability of soil arthropods as bioindicators in protected systems of organic farming
How agro-ecological services crops affect soil arthropod diversity in Mediterranean organic greenhouse production
No full textConventionalization of organic agriculture through input substitution, aimed to fulfill certification requirements, without improvement of natural ecological cycles in agroecosystem, is a relevant concern especially for the organic greenhouse (OGH) sector. Following a holistic approach, more resilient agroecosystems may be designed by taking advantage of Agro-ecological Services Crops (ASC) cultivation during the crops sequence and by using organic matter amendments for the soil fertility management. In this framework, we investigated ecological sustainability of three OGH production systems by studying the soil arthropods taxa. Following systems were under assessment: i) SUBST - bare soil priori to cash crop + organic fertilizer; ii) AGROCOM - ASC as green manure priori to cash crop + compost; and iii) AGROMAN ASC as dead mulch + animal manure. Monitoring of soil arthropods was performed by using pitfall traps and divided in two phases: the pre-crop period (during cultivation of ASC or bare soil in SUBST) and cash crop (kohlrabi) production. Collembola was the most abundant group during cultivation of ASC, in all tested systems and their activity density (AD) was higher in SUBST compared to other two systems. Isopoda, Araneae and Staphylinidae were significantly more abundant in AGROMAN, where manure was applied before ASC sowing. During kohlrabi cultivation Collembola group was confirmed as the most represented in all systems, with the highest values in AGROMAN. Moreover, significant differences were found among the systems for Opiliones, Myriapoda and Staphylinidae groups; with the highest abundance of all these taxa in the AGROCOM system. Results obtained indicate that an agro-ecological practices (ASC cultivation, compost and manure application) could contribute to ecological sustainability and the development of organic agriculture under protected environment
Net carbon flux in organic and conventional olive production systems
No full textAgricultural systems are considered as one of the most relevant sources of atmospheric carbon. However, agriculture has the potentiality to mitigate carbon dioxide mainly through soil carbon sequestration. Some agricultural practices, particularly fertilization and soil management, can play a dual role in the agricultural systems regarding the carbon cycle contributing to the emissions and to the sequestration process in the soil. Good soil and input managements affect positively Soil Organic Carbon (SOC) changes and consequently the carbon cycle. The present study aimed at comparing the carbon footprint of organic and conventional olive systems and to link it to the efficiency of both systems on carbon sequestration by calculating the net carbon flux. Data were collected at farm level through a specific and detailed questionnaire based on one hectare as a functional unit and a system boundary limited to olive production. Using LCA databases particularly ecoinvent one, IPCC GWP 100a impact assessment method was used to calculate carbon emissions from agricultural practices of both systems. Soil organic carbon has been measured, at 0-30 cm depth, based on soil analyses done at the IAMB laboratory and based on reference value of SOC, the annual change of SOC has been calculated. Substracting sequestrated carbon in the soil from the emitted on resulted in net carbon flux calculation. Results showed higher environmental impact of the organic system on Global Warming Potential (1.07 t CO2 eq. yr-1) comparing to 0.76 t CO2 eq. yr-1 in the conventional system due to the higher GHG emissions caused by manure fertilizers compared to the use of synthetic foliar fertilizers in the conventional system. However, manure was the main reason behind the higher SOC content and sequestration in the organic system. As a resultant, the organic system showed higher net carbon flux (-1.7 t C ha-1 yr-1 than -0.52 t C ha-1 yr-1 in the conventional system reflecting higher efficiency as a sink for atmospheric CO2 (the negative value of Net C flux indicates that a system is a net sink for atmospheric CO2). In conclusion, this study illustrates the importance of including soil carbon sequestration associated with CO2 emissions in the evaluation process between alternatives of agricultural systems. Thus, organic olive system offers an opportunity to increase carbon sequestration compared to the conventional one although it causes higher C emissions from manure fertilization. Keywords: Net carbon flux, GHG, organic, olive, soil organic carbo
Cover crops as a part of organic greenhouse rotation: Implication on soil arthropods dynamics
No full textSoil arthropods have been recognized as indicators of habitat quality and diversity in open field organic systems, while in organic greenhouses (OG) research is still rather limited. Conservation and promotion of arthropods diversity are often unrelated to the identity of the components that provide it like cover crops (CC). CC may enhance arthropods diversity and provide wide range of ecological services (e.g. shelter, soil temperature moderation). However, the use of the CC in OG is not a widespread practice because farmers aim to produce cash crops for the market during the whole year. The present study aims to investigate the soil arthropods dynamics during CC growth cycle and following cucumber cultivation within a rotation plan in OG under Mediterranean conditions. Three organic farming systems were evaluated in term of soil arthropods dynamics and abundance: i) a simplified organic production system based on organic commercial fertilizers (SUBST); ii) organic production system based on animal manure amendment and cover crops (AGROMAN), and iii) organic production system based on green manuring of cover crops and on-farm compost amendment (AGROCOM). Assessment was based on pitfall traps monitoring and classification of individuals in macrogroups. Spiders, rove beetles and isopods were more abundant in CC treatments, while other groups did not differ significantly among systems. Cucumber cultivation revealed different patterns, with more uniform results among the systems, except for AGROMAN. Results show that cover crops influenced soil arthropod diversity and their suitability to be used as bioindicators of ecological sustainability
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
How agro-ecological services crops affect soil arthropod diversity in Mediterranean organic greenhouse production
No full textConventionalization of organic agriculture through input substitution, aimed to fulfill certification requirements, without improvement of natural ecological cycles in agroecosystem, is a relevant concern especially for the organic greenhouse (OGH) sector. Following a holistic approach, more resilient agroecosystems may be designed by taking advantage of Agro-ecological Services Crops (ASC) cultivation during the crops sequence and by using organic matter amendments for the soil fertility management. In this framework, we investigated ecological sustainability of three OGH production systems by studying the soil arthropods taxa. Following systems were under assessment: i) SUBST - bare soil priori to cash crop + organic fertilizer; ii) AGROCOM - ASC as green manure priori to cash crop + compost; and iii) AGROMAN - ASC as dead mulch + animal manure. Monitoring of soil arthropods was performed by using pitfall traps and divided in two phases: the pre-crop period (during cultivation of ASC or bare soil in SUBST) and cash crop (kohlrabi) production. Collembola was the most abundant group during cultivation of ASC, in all tested systems and their activity density (AD) was higher in SUBST compared to other two systems. Isopoda, Araneae and Staphylinidae were significantly more abundant in AGROMAN, where manure was applied before ASC sowing. During kohlrabi cultivation Collembola group was confirmed as the most represented in all systems, with the highest values in AGROMAN. Moreover, significant differences were found among the systems for Opiliones, Myriapoda and Staphylinidae groups; with the highest abundance of all these taxa in the AGROCOM system. Results obtained indicate that an agro-ecological practices (ASC cultivation, compost and manure application) could contribute to ecological sustainability and the development of organic agriculture under protected environment
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