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1.
J Environ Manage ; 341: 118055, 2023 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-37141725

RESUMEN

Second-generation bioenergy, a carbon neutral or negative renewable resource, is crucial to achieving India's net-zero emission targets. Crop residues are being targeted as a bioenergy resource as they are otherwise burned on-field, leading to significant pollutant emissions. But estimating their bioenergy potential is problematic because of broad assumptions about their surplus fractions. Here, we use comprehensive surveys and multivariate regression models to estimate the bioenergy potential of surplus crop residues in India. These are with high sub-national and crop disaggregation that can facilitate the development of efficient supply chain mechanisms for its widespread usage. The estimated potential for 2019 of 1313 PJ can increase the present bioenergy installed capacity by 82% but is likely insufficient alone to meet India's bioenergy targets. The shortage of crop residue for bioenergy, combined with the sustainability concerns raised by previous studies, imply a need to reassess the strategy for the use of this resource.


Asunto(s)
Agricultura , Contaminantes Ambientales , India , Carbono
2.
Environ Res ; 205: 112409, 2022 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-34838761

RESUMEN

The sources and state of sedimentary organic matter (SOM) in fresh water aquatic systems are important to understand the carbon cycling in terrestrial environments. The composition of organic matter in the lake sediments demonstrates the physical and chemical condition of the lake ecosystems. However, the systematic and structured investigations focussed on to understand the source and fate of organic matters within eutrophic lakes is still far from clear. The present study is focusing on the implications of amino acids (AA), aliphatic hydrocarbons and bulk geochemical (C/N, δ15N) proxies to understand the distribution, sources and state of sedimentary organic matter in Ahansar Lake from Kashmir valley, India. The relatively low C/N ratios along with high AA contents indicate enhanced aquatic productivity in the lake system. Likewise, the dominance of the mid-chain monomethyl alkanes (MMAs), highly branched isoprenoids (HBIs), botryococcenes, steroids and triterpenoids suggest OM sourced from periphyton remains. Furthermore, the presence of C27, C28 and C29 diagenetically altered steroids also reflects a major algal contribution. The spatial variability of Paq demonstrates their applicability as a proxy for the contribution of aquatic vegetation. The ratio of individual amino acids (oxic/anoxic ratio) and low Pr/Ph (pristane/phytane) values indicate anoxic nature of the current depositional environment. This also leads to significant organic matter preservation as revealed by amino acid indices (e.g., degradation index - DI and reactivity index - RI). These data collectively demonstrate the systematic investigation and comprehensive understanding of source of sedimentary organic matters and respective depositional condition via multiple indicators. Overall, understanding the OM molecular composition and its spatial heterogeneity in a lake system is important to better constrain the fate of organic carbon, and assess the pollution risks as well as adopt relevant management strategies.


Asunto(s)
Sedimentos Geológicos , Contaminantes Químicos del Agua , Aminoácidos , Ecosistema , Monitoreo del Ambiente , Sedimentos Geológicos/química , Hidrocarburos/análisis , Lagos , Contaminantes Químicos del Agua/análisis
3.
Sci Rep ; 13(1): 3090, 2023 02 22.
Artículo en Inglés | MEDLINE | ID: mdl-36813837

RESUMEN

Dachigam National Park (DNP), in Zabarwan mountains of north-western Himalaya constitutes a region of high biodiversity with greater endemism. DNP is known for its unique micro-climate together with distinct vegetational zones providing home to variety of threatened and endemic plant, animal, and bird species. However, studies on soil microbial diversity in fragile ecosystems of north-western Himalaya in general and DNP in particular are lacking. This was thus a maiden attempt to study variations in soil bacterial diversity of DNP with respect to changing soil physico-chemical properties, vegetation, and altitude. Soil parameters depicted significant variations among different sites with highest values for temperature, OC, OM and TN being 22.2 ± 0.75 °C, 6.53 ± 0.32%, 11.25 ± 0.54%, 0.545 ± 0.04% from site-2 (low altitudinal grassland site) in summer and lowest of 5.1 ± 0.65 °C, 1.24 ± 0.26%, 2.14 ± 0.45% and 0.132 ± 0.04% at site-9 (high altitudinal mixed pine site) in winter. Bacterial CFU showed significant correlations with soil physico-chemical attributes. This study led to the isolation and identification of 92 morphologically varied bacteria with the highest (15) from site-2 and lowest (04) from site-9 which post BLAST analysis (via 16S rRNA analysis) depicted presence of only 57 distinct bacterial species under taxonomic phylum, Firmicutes and Proteobacteria. Nine species were widely spread (i.e., isolated from > 3 sites), however, most bacteria (37) were restricted to a particular site. Diversity indices ranged between 1.380 to 2.631 (Shannon-Weiner's index); 0.747 to 0.923 (Simpson's index) with highest values for site-2 and lowest for site-9. Index of similarity was highest (47.1%) between riverine sites (site-3 and site-4) whereas two mixed pine sites (site-9 and site-10) showed no similarity.


Asunto(s)
Ecosistema , Suelo , Animales , Suelo/química , ARN Ribosómico 16S/genética , Parques Recreativos , Bacterias/genética , Biodiversidad , Microbiología del Suelo
4.
PLoS One ; 18(3): e0283677, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36996152

RESUMEN

In this work, a psychrotrophic bacteria producing cold-active protease, was obtained from Dachigam National Park, an ecologically significant habitat in Western Himalayas owing to its varied endemic and endangered flora and fauna. This isolate was identified as Bacillus sp. HM49 via phenotypic, Gram staining, bio-chemical and 16S rRNA gene identification. Isolate HM49 when tested for proteolytic activity revealed prominent hydrolytic zone with the most production at 20 °C and pH, 8.0 post 72 h incubation. This enzyme was purified, enhancing its specific activity to 61.15 U/mg and its characterization studies revealed it to be a cold-alkaline protease being active in a wide pH (6.0-12) and temperature (5-40 °C) range. Amplification of CAASPR gene of HM49 was performed, followed by enzyme-substrate docking studies and MMGBSA providing details about its type, molecular weight validation as well as functional applications. The purified protease of HM49 was tested for laundry applications and the enzyme was found to be compatible with majority of the detergents tested. Its potential as an eco-friendly detergent additive was further validated by wash performance test as it effectively removed recalcitrant blood stains at a low temperature of 20 °C that could be beneficial for fine garments like silk which preferably need cold washing.


Asunto(s)
Bacillus , Péptido Hidrolasas/genética , ARN Ribosómico 16S/genética , Proteínas Bacterianas/química , Endopeptidasas/genética , Endopeptidasas/química , Bacterias/genética , Temperatura , Concentración de Iones de Hidrógeno , Estabilidad de Enzimas , Detergentes/química
5.
Sci Total Environ ; 904: 166566, 2023 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-37643710

RESUMEN

The focus of the present study was to assess the dynamics of wetland ecosystem health in both urban and rural settings situated in the high-altitude Kashmir Himalayan ecoregion. The basic aim was to identify the drivers responsible for wetland degradation in order to sustain ecosystem services effectively. To achieve this, we examined water quality, trophic status, fish species diversity and human disturbances by analyzing changes in land use and land cover (LULC) since 1980. For the limnological characterization of the two wetlands, we evaluated a total of 21 physico-chemical parameters at 24 sites. Two-way analysis of variance revealed significant (p < 0.05) spatial and temporal variability in the water quality parameters. The trophic state index values of 67.7 and 76.7 indicated that the rural and urban wetlands were in eutrophic and hypertrophic status, respectively, signifying potential environmental stress. The data on fish fauna indicated a decline in fish species over the past 40 years, particularly the schizothoracine species. Urban wetlands showed a more significant decrease in species (06) compared to rural wetlands (01). LULC mapping and change analysis employing the visual interpretation technique showed significant transformations in the immediate catchment of wetlands. Substantial growth in the built-up (433.2 % and 2620 %) and decrease in aquatic vegetation (-83.4 % and - 97.5 %) in the immediate catchment was recorded in both the urban and rural wetlands respectively from 1980 to 2020. Our findings demonstrated a relationship between LULC classes and water quality parameters, with an increase in built-up and road areas showing a significant positive correlation with the rise in decadal mean values of total phosphorus, orthophosphorus, nitrate nitrogen, ammonical nitrogen, and calcium content. Based on these observations, we concluded that changes in land use and land cover within the immediate catchment areas of the wetlands were the primary drivers responsible for the deterioration of wetland ecosystem health.


Asunto(s)
Ecosistema , Humedales , Humanos , Altitud , Monitoreo del Ambiente/métodos , Conservación de los Recursos Naturales , Nitrógeno
6.
Environ Sci Pollut Res Int ; 29(51): 76485-76500, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-35931843

RESUMEN

BACKGROUND: Environmental noise is a pervasive pollutant that is one of the greatest environmental threats to mental, physiological and psychological well-being and has a significant global health burden associated with it. Many epidemiological studies indicate long-term relationship of noise pollution with wide range of metabolic, cardio-vascular and respiratory disorders and diseases. OBJECTIVE: The goal of this study was to thoroughly analyse available literature on public health implications and various underlying biological mechanisms associated with ambient noise exposure, taking into account both objective and subjective measures of noise exposure. METHODS: A search of literature for review on environmental noise and associated cardiovascular, mental health and metabolic implications on human health was done using Web of Science, Google Scholar and PubMed databases. DISCUSSION: Experimental studies indicate that noise exposure leads to endocrine effects, increased incidence of diabetes, impairment of cognitive performance, sleep disturbance and annoyance. Epidemiological evidence indicates that high levels of noise, particularly at night, may cause arterial hypertension and endothelial dysfunction due to higher level of stress hormones and oxidative stress. An increased incidence of cardio-vascular diseases like myocardial infarction, heart rate, ischemic heart disease, stroke and heart failure is associated with noise-induced mental stress. Furthermore, psychological and mental health issues like anxiety and depression are also related with exposure to noise pollution. CONCLUSION: This article summarises a comprehensive and systematic knowledge established in recent noise research with the spotlight on cardiovascular, metabolic and mental health disorders of environmental noise, providing unique understanding into underlying mechanisms.


Asunto(s)
Enfermedades Cardiovasculares , Contaminantes Ambientales , Hipertensión , Humanos , Ruido/efectos adversos , Salud Mental , Hipertensión/etiología , Hormonas , Exposición a Riesgos Ambientales , Enfermedades Cardiovasculares/epidemiología , Enfermedades Cardiovasculares/etiología
7.
Biomolecules ; 11(1)2021 01 18.
Artículo en Inglés | MEDLINE | ID: mdl-33477596

RESUMEN

A novel temperature stable alkaline protease yielding bacteria was isolated from the soils of Dachigam National Park, which is known to be inhabited by a wide variety of endemic plant and animal species of Western Himalaya. This high-potential protease producing isolate was characterized and identified as Bacillus amyloliquefaciens strain HM48 by morphological, Gram's staining and biochemical techniques followed by molecular characterization using 16S rRNA approach. The extracellular protease of B. amyloliquefaciens HM48 was purified by precipitating with ammonium sulfate (80%), followed by dialysis and Gel filtration chromatography increasing its purity by 5.8-fold. The SDS-PAGE analysis of the purified enzyme confirmed a molecular weight of about ≈25 kDa. The enzyme displayed exceptional activity in a broad temperature range (10-90 °C) at pH 8.0, retaining its maximum at 70 °C, being the highest reported for this proteolytic Bacillus sp., with KM and Vmax of 11.71 mg/mL and 357.14 µmol/mL/min, respectively. The enzyme exhibited remarkable activity and stability against various metal ions, surfactants, oxidizing agent (H2O2), organic solvents and displayed outstanding compatibility with widely used detergents. This protease showed effective wash performance by exemplifying complete blood and egg-yolk stains removal at 70 °C and efficiently disintegrated chicken feathers making it of vital importance for laundry purpose and waste management. For functional analysis, protease gene amplification of strain HM48 yielded a nucleotide sequence of about 700 bp, which, when checked against the available sequences in NCBI, displayed similarity with subtilisin-like serine protease of B. amyloliquefaciens. The structure of this protease and its highest-priority substrate ß-casein was generated through protein modeling. These protein models were validated through futuristic algorithms following which protein-protein (protease from HM48 and ß-casein) docking was performed. The interaction profile of these proteins in the docked state with each other was also generated, shedding light on their finer details. Such attributes make this thermally stable protease novel and suitable for high-temperature industrial and environmental applications.


Asunto(s)
Bacillus amyloliquefaciens/enzimología , Calor , Péptido Hidrolasas/metabolismo , Microbiología del Suelo , Animales , Bacillus amyloliquefaciens/citología , Bacillus amyloliquefaciens/genética , Bacillus amyloliquefaciens/aislamiento & purificación , Caseínas/metabolismo , Pollos , Ácido Edético/farmacología , Estabilidad de Enzimas/efectos de los fármacos , Plumas , Geografía , Concentración de Iones de Hidrógeno , India , Iones , Cinética , Metales/farmacología , Pruebas de Sensibilidad Microbiana , Simulación del Acoplamiento Molecular , Peso Molecular , Oxidantes/farmacología , Péptido Hidrolasas/genética , Proteolisis/efectos de los fármacos , ARN Ribosómico 16S/genética , Reproducibilidad de los Resultados , Solventes , Especificidad por Sustrato/efectos de los fármacos , Tensoactivos/farmacología
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