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1.
Food Secur ; 13(4): 1029-1047, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34221190

RESUMO

Agriculture is the most natural resource-intensive and climate-sensitive sector. This study examines the perceptions and attitudes of small family farmers toward climate change and identifies adaptation strategies supporting household food security in the Middle Eastern context, Lebanon. The study uses cross-sectional, primary data of households that own small family farms in the Central Bekaa region. The results show that the majority of the households believe that climate change is occurring, has adverse impacts on livelihoods, and is attributable to human factors. They perceived an increase in temperature and a decrease in rainfall patterns over the last 20 years. In response, the households used multiple agricultural practices to adapt to climate change. Based on the Household Food Insecurity Access Scale (HFIAS) scores, only 7.5% of the households were food secure, while 89% were mild to moderately food insecure. Generally, the households had modest access to nutritious diets. All the households used two or more environmentally sustainable agricultural practices. However, the use of multiple environmentally sustainable practices did not correlate with improved food security. This latter result may be due to the limited knowledge of the farmers about trade-offs between various climate change adaptation measures. The findings suggest the need to refocus research from the question of whether small family farmers are willing to adopt (or not) climate change adaptation practices to identifying those practices that are capable of balancing economic, social, and environmental goals in a specific context.

2.
Environ Geochem Health ; 42(8): 2293-2303, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31388812

RESUMO

Trace metals are found naturally in soil. However, the increase in industrial and agricultural polluting activities has increased trace metal contamination and raised high concerns in the public health sector. The study was conducted on Origanum syriacum, one of the most consumed herbs in the Middle East, and was divided into three parts. (1) Pot experiment: to study the effect of Cd, Pb, or Ni levels in soil on their uptake by O. syriacum. (2) Field samples: collected from major agricultural regions in Lebanon to analyze Cd, Pb, and Ni concentrations in soil and leaves. (3) Sale outlets samples: to measure the levels of Cd, Pb, and Ni in O. syriacum tissues in the market. Results showed that there was a positive correlation between levels of Cd, Pb, and Ni in soil and those in O. syriacum tissues. None of the field samples contained Pb or Ni that exceeded the maximum allowable limits (MAL). Three samples collected from heavily poultry-manured soil contained Cd higher than the MAL. Samples collected from sale outlets did not exceed the MAL for Ni but two exceeded the MAL for Cd and one for Pb. Trace metal contamination is not a major concern in O. syriacum produced in Lebanon. Only one mixture sample from a sale outlet was higher in Pb than the MAL and three samples from heavily manured fields exceeded the MAL for Cd.


Assuntos
Cádmio/farmacocinética , Chumbo/farmacocinética , Níquel/farmacocinética , Origanum/metabolismo , Poluentes do Solo/farmacocinética , Monitoramento Ambiental/métodos , Contaminação de Alimentos/análise , Líbano , Esterco , Origanum/química , Origanum/efeitos dos fármacos , Folhas de Planta/química , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/metabolismo
3.
J Environ Sci Health B ; 48(7): 570-4, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23581689

RESUMO

Antibiotics are extensively given to livestock to promote growth and reduce diseases. Therefore, animal manure often contains antibiotics. Once manure is applied to agricultural land to improve soil productivity, crops would be exposed to antibiotics which may persist in soils from a few to several hundred days. The objective of this study was to evaluate the uptake of gentamicin and streptomycin by carrot (Daucus carota), lettuce (Lactuca sativa) and radish (Rhaphanus sativus) from manure-amended soil. The treatments were 0, 0.5 and 1 mg of antibiotic kg⁻¹ of soil. Two pot experiments were carried out in the greenhouse. The first was conducted on the three crops and the second exclusively on radish. In radish, the increase in the concentrations of gentamicin was significant between the 0 and both of 0.5 and 1.0 mg kg⁻¹ treatments, but not significant between the 0.5 and 1.0 mg kg⁻¹. The average values were 35.5, 60.0 and 57.4 µg kg⁻¹ for the 0, 0.5 and 1 mg kg⁻¹ rates, respectively. However, the increase in streptomycin concentration in radish was not significant between the three treatments, and the average values were, 12.1, 15.2 and 17.4 µg kg⁻¹ for the 0, 0.5 and 1 mg kg⁻¹ rates, respectively. In carrot roots and lettuce leaves no significant increase in the concentrations of gentamicin or streptomycin was observed between the treatments. The three crops absorbed relatively higher amounts of gentamicin (small molecule) than streptomycin (large molecule). Generally the levels of antibiotics in plant tissue increased with increasing the antibiotic concentration in the manure (1 mg kg⁻¹ > 0.5 mg kg⁻¹).


Assuntos
Antibacterianos/metabolismo , Daucus carota/metabolismo , Lactuca/metabolismo , Esterco/análise , Raphanus/metabolismo , Poluentes do Solo/metabolismo , Antibacterianos/análise , Daucus carota/química , Contaminação de Alimentos/análise , Lactuca/química , Raphanus/química , Solo/análise , Poluentes do Solo/análise
4.
J Environ Sci Health B ; 39(5-6): 757-64, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15620084

RESUMO

A laboratory pot experiment was conducted to study the effect of amending soil with four different sources of organic matter on the degradation rate of alpha and beta endosulfan isomers. Poultry by-product meal, poultry manure, dairy manure, and municipal solid waste compost were cured, dried, ground (<1 mm) and thoroughly mixed with a calcareous soil at a rate of 2% and placed in plastic pots. Endosulfan was added at the rate of 20 mg kg(-1). The moisture level was kept near field capacity and the pots were kept at room temperature. Soil sub-samples, 100 g each, were collected from every pot at days 1, 8, 15, 22, 29, 43, and 57 for the measurement of endosulfan isomers. Endosulfan residues were extracted from the soil samples with acetone. The supernatant was filtered through anhydrous sodium sulphate, 5 mL aliquot was diluted to 25 mL with hexane, mixed well, and then two sub-samples from the filtrates were analyzed for alpha and beta endosulfan isomers by gas chromatography. The results indicated that the half-life (T(1/2)) of alpha-endosulfan in the poultry by-product meal treatment was 15 days compared to about 22 days in the other treatments. The T(1/2) of beta-endosulfan was 22 days in the poultry by-product meal treatment and followed a bi-phasic pattern, 57 days in the municipal solid waste compost treatment and the extrapolated T(1/2) was about 115 days for the other three treatments.


Assuntos
Endossulfano/metabolismo , Inseticidas/metabolismo , Animais , Biodegradação Ambiental , Bovinos , Esterco , Compostos Orgânicos , Aves Domésticas , Eliminação de Resíduos , Estereoisomerismo
5.
J Environ Sci Health B ; 39(2): 273-83, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15132334

RESUMO

The present study was conducted to evaluate the levels of residual DDT in Lebanese soils. A total of 113 surface soil samples were collected for analysis from three major agricultural regions in the country: Mount Lebanon, Beqa'a valley and the coastal plain. The values of residual DDT in soils ranged between 0 and 1190 ng g(-1). The majority of the analyzed soil samples were free or contained very low concentrations of DDE. Only two surface soil samples, which were collected from urban areas with high human activities, contained relatively high concentrations of residual DDT. The levels of residual DDT in all of the analyzed soil samples were within the permissible limits for agricultural soils.


Assuntos
DDT/análise , Monitoramento Ambiental , Inseticidas/análise , Resíduos de Praguicidas/análise , Poluentes do Solo/análise , Agricultura , Cromatografia Gasosa/métodos , Diclorodifenil Dicloroetileno/análise , Ensaio de Imunoadsorção Enzimática/métodos , Líbano , Solo/análise
6.
J Environ Sci Health B ; 38(2): 111-9, 2003 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12617550

RESUMO

Three different calcareous soil samples from Lebanon were analyzed for total DDT pesticide residue using GC and ELISA methods. Two experiments were conducted on three different calcareous soil samples. In each experiment, triplicates of 5 gm soil samples were each fortified with standard solutions of DDE to reach concentrations of 0, 5, 25, 50, 100 and 200 ng g(-1) and allowed to equilibrate at room temperature for 6 hours. Each sample was then extracted with 25 mL of 90% methanol by shaking in glass bottles on a mechanical shaker for 16 hours. The bottles were allowed to stand for 30 minutes and aliquots were taken from the clear supernatant for analyses without further cleanup. The total DDT in the extract was measured in triplicate by GC and ELISA. The results indicated that the two methods were highly correlated (R = 0.955-0.994). Differences in soil properties did not affect the accuracy of the detection limits of ELISA. Immunoassay technique can be used for rapid and accurate measurement of total DDT residues in mineral calcareous soils in Lebanon.


Assuntos
Cromatografia Gasosa/métodos , DDT/análise , Ensaio de Imunoadsorção Enzimática/métodos , Resíduos de Praguicidas/análise , Poluentes do Solo/análise , Carbonato de Cálcio/análise , Relação Dose-Resposta a Droga , Líbano , Sensibilidade e Especificidade , Solo/análise
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