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1.
Sci Total Environ ; 857(Pt 3): 159695, 2023 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-36302433

RESUMEN

The strategic goals of the United Nations and the Aichi Targets for biodiversity conservation have not been met. Instead, biodiversity has continued to rapidly decrease, especially in developing countries. Setting a new global biodiversity framework requires clarifying future priorities and strategies to bridge challenges and provide representative solutions. Hyper-arid, arid, and semi-arid lands (herein, arid lands) form about one third of the Earth's terrestrial surface. Arid lands contain unique biological and cultural diversity, and biodiversity loss in arid lands can have a disproportionate impact on these ecosystems due to low redundancy and a high risk of trophic cascades. They contain unique biological and cultural diversity and host many endemic species, including wild relatives of key crop plants. Yet extensive agriculture, unsustainable use, and global climate change are causing an irrecoverable damage to arid lands, with far-reaching consequences to the species, ground-water resources, ecosystem productivity, and ultimately the communities' dependant on these systems. However, adequate research and effective policies to protect arid land biodiversity and sustainability are lacking because a large proportion of arid areas are in developing countries, and the unique diversity in these systems is frequently overlooked. Developing new priorities for global arid lands and mechanisms to prevent unsustainable development must become part of public discourse and form the basis for conservation efforts. The current situation demands the combined efforts of researchers, practitioners, policymakers, and local communities to adopt a socio-ecological approach for achieving sustainable development (SDGs) in arid lands. Applying these initiatives globally is imperative to conserve arid lands biodiversity and the critical ecological services they provide for future generations. This perspective provides a framework for conserving biodiversity in arid lands for all stakeholders that will have a tangible impact on sustainable development, nature, and human well-being.


Asunto(s)
Conservación de los Recursos Naturales , Ecosistema , Humanos , Biodiversidad , Agricultura , Cambio Climático
2.
Biol Pharm Bull ; 42(4): 552-560, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30930415

RESUMEN

Field surveys of Ephedra plants were conducted in the Zaravshan Mountains of Tajikistan. E. equisetina, E. intermedia, and their putative hybrids were collected. They were identified based on their phenotypes and their sequences of nuclear ribosomal DNA internal transcribed spacer 1 (ITS1) region. Sequencing and species-specific PCR analyses of their ITS1 sequences revealed six putative hybrids of E. equisetina and E. intermedia. The total ephedrine and pseudoephedrine content of most of the Ephedra samples collected in Tajikistan were higher than the 0.7% lower limit prescribed by the Japanese pharmacopoeia, 17th edition (JP17), and varied from 0.34 to 3.21% by dry weight. The total alkaloid level of E. intermedia (11E08-1) cultivated in Japan varied from 1.77 to 2.30% by dry weight, which was much higher than the 0.7% lower limit prescribed by JP17.


Asunto(s)
Alcaloides/análisis , Ephedra , Altitud , Cruzamientos Genéticos , Ephedra/química , Ephedra/genética , Efedrina/análisis , Hibridación Genética , Tallos de la Planta/química , Tallos de la Planta/genética , Seudoefedrina/análisis , Tayikistán
3.
Environ Technol ; 40(9): 1178-1184, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29235928

RESUMEN

The steam gasification of algal biomass (Cladophora glomerata L.) in presence of alkali and alkaline-earth metal compounds catalysts was studied to enhance the yield of syngas and reduce its tar content through cracking and reforming of condensable fractions. The commercial catalysts used include NaOH, KHCO3, Na3PO4 and MgO. The gasification runs carried out with a research scale, biomass gasification unit, show that the NaOH has a strong potential for production of hydrogen, along with the added advantages of char converting and tar destruction, allowing enhancement of produced syngas caloric value. When the temperature increased from 700°C to 900°C, the tar content in the gas sharply decreased, while the hydrogen yield increased. Increasing steam/biomass ratio significantly increased hydrogen yield and tar destruction; however, the particle size in the range of 0.5-2.5 mm played a minor role in the process.


Asunto(s)
Álcalis , Hidrógeno , Biomasa , Gases , Metales
4.
Environ Technol ; 40(6): 749-755, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29141510

RESUMEN

Gasification is one of the most important thermochemical routes to produce both synthesis gas (syngas) and chars. The quality of produced syngas wieldy depends on the operating conditions (temperature, residence time, heating rate, and gasifying agent), hydrodynamic properties of gasifier (particle size, minimum fluidization velocity, and gasifier size), and type of feedstock (coal, biomass, oil, and municipal solid wastes). In the present study, simulation of syngas production via circulating fluidized bed (CFB) gasification of algal biomass (Cladophora glomerata L.) at different gasifying agents and particle sizes was carried out, using Aspen Plus simulator. The model which has been validated by using experimental data of the technical literature was used to evaluate the influence of operating conditions on gas composition and performance parameters. The results show that biomass gasification using pure oxygen as the gasification agent has great potential to improve the caloric value of produced gas and performance indicators. It was also found that the produced gas caloric value, syngas yield, and performance parameters (CCE and CGE) increase with reaction temperature but are inversely proportional to the biomass particle size.


Asunto(s)
Dióxido de Carbono , Gases , Biomasa , Carbón Mineral , Residuos Sólidos
5.
J Ethnobiol Ethnomed ; 2: 18, 2006 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-16584547

RESUMEN

BACKGROUND: Hitherto available sources from literature mentioned several wild growing Allium species as "edible" or "medicinally used" but without any further specification. METHODS: New data were gained during recent research missions: Allium plants were collected and shown to the local population which was asked for names and usage of these plants. RESULTS: Information was collected about current medical applications of sixteen wild species, nine of which belong to different sections of Allium subgenus Melanocrommyum. These plants are used against headache, cold, and stomach problems, and are mostly applied fresh or after boiling. CONCLUSION: Close taxonomic relatives of the common onion were used similar to cultivated onion species, but medical use like garlic was mostly reported for species taxonomically not related to garlic.


Asunto(s)
Allium , Conocimientos, Actitudes y Práctica en Salud , Medicina Tradicional , Extractos Vegetales/uso terapéutico , Femenino , Ajo , Humanos , Masculino , Persona de Mediana Edad , Cebollas , Tayikistán , Uzbekistán
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