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1.
J Environ Manage ; 329: 117082, 2023 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-36577302

RESUMEN

-Enhancing the productivity of rainfed crops, especially rice, while coping with climate adversities and saving critical natural resources is essential for ensuring the food and nutrition security of a growing population. With this context, the present study was undertaken to validate promising farm innovation and adaptation practices used by small-medium landholding farmers for rice cultivation in eastern Uttar Pradesh (UP), north India, as well as to examine the sustainability of innovative practices for large-scale adoption. For this, a 3-year study comprising extensive field surveys and experiments was undertaken to compare single transplantation (ST) and double transplantation (DT) in rice along with organic addition (farm-yard manure, FYM) on crop growth, yield, climate resilience, soil quality, and overall sustainability i.e., social (women involvements and labour productivity), environmental (water productivity and nutrient use efficiency), and economic (benefit:cost ratio) dimensions of sustainability. Field experiments were conducted in triplicate using two local rice varieties (MotiNP-360 and Sampurna Kaveri) in two agroclimatic zones, namely the middle Gangetic plains and the Vindhyan zone, in the Mirzapur district of eastern Uttar Pradesh. The DT practices of rice with and without farm yard manure (FYM) (replacing at a dose of 25% NPK) were evaluated over conventional methods of rice cultivation (i.e., ST, as control) and analysis was done periodically. The DT practice improved growth (p < 0.05), percent fertile tiller and grain (p < 0.05), and rice yield (15-20% higher than ST), while also improving soil quality, yield indices, water and labour productivity, and the benefit-cost ratio. The DT practice also resulted in early maturity (10-15 days earlier than ST), created more labour days for women, decreased lodging and pest/disease incidence, as well as a subsequent reduction in the use of synthetic chemical pesticides and associated environmental costs. Importantly, the residual effects of FYM application significantly improved (p < 0.05) the grain yield in subsequent years of cropping. Optimizing DT cultivation practices, preferably with FYM input for various agro-climatic regions, is essential for large-scale sustainable rice production under changing climatic conditions.


Asunto(s)
Agricultura , Oryza , Femenino , Humanos , Agricultura/métodos , Estiércol , Suelo , Grano Comestible , India
2.
Environ Monit Assess ; 192(4): 260, 2020 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-32240367

RESUMEN

Thermal power plants (TPPs) have emerged as a major source of air, water, and soil pollution because of the presence of many toxic metals. The presence of mercury (Hg) in fly ash has proven to be toxic in nature because of its tendency to get bioaccumulated and biomagnified in the food chain. The aim of the present study was to understand the presence of toxic Hg in the feathers of wetland birds undertaking the study around a TPP located in Nagpur, India. Local wetland birds especially cattle egrets, heron, and Moorhen were commonly observed dwelling close to fly ash ponds for various purposes (roosting, breeding, feeding, etc.). Samples of fly ash, soil, water, plants, and bird feather were collected, cleaned, and processed for Hg analysis. A mercury analyzer was used to assess the concentration of toxic levels of Hg in samples. Our results reflect leaching of Hg in soil and uptake by plant samples, whereas in water, ash, and bird feather samples concentrations of Hg were fairly below the prescribed limits (World Health Organization). A non-invasive method for understanding the mercury concentration in wetland birds has been established as a potential important monitoring tool to track the fate of toxic metal Hg in the food chain. In summary, our results indicate fairly low Hg levels in feather samples projecting non-invasive biomonitoring as a promising strategy. The study also suggests that a comprehensive monitoring action plan in place for Hg and other toxic metals in the food chain that comes from TPP will be efficient to avoid any pitfalls. Graphical abstract.


Asunto(s)
Monitoreo Biológico , Aves , Contaminantes Ambientales/análisis , Centrales Eléctricas , Animales , Pollos , Monitoreo del Ambiente , Plumas , India , Mercurio
3.
Sci Total Environ ; 689: 1304-1315, 2019 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-31466167

RESUMEN

The United Nations General Assembly has recently declared 2021-2030 as the 'International Decade on Ecosystem Restoration' for facilitating the restoration of degraded and destroyed terrestrial and marine systems for regaining biodiversity and ecosystem services, creating job opportunities and also to fight against climate change. One of the prime focus is the restoration of ~350 mha of degraded land across the world for attaining the UN-Sustainable Development Goals. Pesticides are one of the major causes of land pollution and hexachlorocyclohexanes (HCHs, including technical-HCH and γ-HCH) is one of the widely used organochlorine pesticides during the past seven decades before α-, ß-, and γ-HCH was listed in the Stockholm Convention in 2009. The widespread pollution of HCHs has been reported from every sphere of the environment and ~7 Mt of HCHs residues have been dumped worldwide near the production sites. HCHs isomers have higher volatility, water solubility and long-range atmospheric transport ability which further facilitates its entry into various environmental compartments. Therefore, the restoration and management of HCHs polluted land is urgently required. Despite various pilot-scale studies have been reported for the remediation of HCHs polluted land, they are not successfully established under the field conditions. This is mainly due to the high concentration of HCHs residues in the contaminated soil and also due to its toxicity and highly persistent nature, which increases the complexity of the onsite remediation. Here we provide a novel approach i.e. sequential and integrated remediation approach (SIRA) for the restoration of HCHs contaminated land by the integrated use of agroresidues along with the application of HCHs degrading microorganisms and chemical amendments followed by the plant-based clean-up techniques using grasses, herbs, shrubs and trees in a sequential manner. SIRA provides cost effective solution with enhanced ecological and socioeconomic benefits for the sustainable restoration of HCHs contaminated sites.


Asunto(s)
Ecosistema , Política Ambiental , Restauración y Remediación Ambiental , Hexaclorociclohexano , Naciones Unidas , Contaminación Ambiental
4.
Artículo en Inglés | MEDLINE | ID: mdl-17719837

RESUMEN

cis-Bis(2,2'-bipyridyl)dichlororuthenium(II)dihydrate complexed with Schiff bases salen (L1H2) and salophen (L2H2) provides complexes of compositions [Ru(L1)(bpy)2] 1 and [Ru(L2)(bpy)2] 2, respectively with cavity. The structure of these complexes characterized by spectroscopic studies were supported by their optimized geometries based on DFT calculations. Complexes 1 and 2 were then allowed to interact with methanolic solution of sodium perchlorate separately providing corresponding complexes 3 and 4 with the compositions 1.NaClO4 and 2.NaClO4, respectively. The formation constants were then evaluated by monitoring the changes in their UV-visible spectral features upon addition of different amount of sodium salts in the presence of a fixed concentration of the ruthenium complexes at a wavelength 294 nm. Emission (solution), luminescence microscopic and cyclic voltammetric studies of these complexes have also been made.


Asunto(s)
2,2'-Dipiridil/química , Quelantes/química , Rutenio/química , Bases de Schiff/química , Sodio/química , 2,2'-Dipiridil/síntesis química , Fenómenos Químicos , Química Física , Dimetilsulfóxido/química , Electroquímica , Etilenodiaminas/química , Ligandos , Metanol/química , Estructura Molecular , Percloratos/química , Salicilatos/química , Bases de Schiff/síntesis química , Compuestos de Sodio/química , Soluciones/química , Espectrofotometría Ultravioleta
5.
Spectrochim Acta A Mol Biomol Spectrosc ; 133: 846-55, 2014 Dec 10.
Artículo en Inglés | MEDLINE | ID: mdl-25014545

RESUMEN

Quantum-chemical calculations have been performed to evaluate the geometries, bonding nature and harmonic frequencies of the compounds [EUX3] at DFT, DFT-D3, DFT-D3(BJ) and DFT-dDSc levels using different density functionals BP86, BLYP, PBE, revPBE, PW91, TPSS and M06-L. The stretching frequency of UN bond in [NUF3] calculated with DFT/BLYP closely resembles with the experimental value. The performance of different density functionals for accurate UN vibrational frequencies follows the order BLYP>revPBE>BP86>PW91>TPSS>PBE>M06-L. The BLYP functional gives accurate value of the UE bond distances. The uranium atom in the studied compounds [EUX3] is positively charged. Upon going from [EUF3] to [EUCl3], the partial Hirshfeld charge on uranium atom decreases because of the lower electronegativity of chlorine compared to flourine. The Gopinathan-Jug bond order for UE bonds ranges from 2.90 to 3.29. The UE bond dissociation energies vary with different density functionals as M06-L

Asunto(s)
Complejos de Coordinación/química , Uranio/química , Electrones , Modelos Moleculares , Teoría Cuántica
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