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81.
In this study, we surveyed diversity in a range of local crops in the Lume and Gimbichu districts of Ethiopia, together with the knowledge of local people regarding crop uses, socio-economic importance, conservation, management and existing threats. Data were collected using semistructured interviews and participant observation. The study identified 28 farmers' varieties of 12 crop species. Among these, wheat (Triticum turgidum) and tef (Eragrostis tef) have high intra-specific diversity, with 9 and 6 varieties respectively. Self-seed supply or seed saving was the main (80?%) source of seeds for replanting. Agronomic performance (yield and pest resistance), market demand, nutritional and use diversity attributes of the crop varieties were highlighted as important criteria for making decisions regarding planting and maintenance. Over 74?% of the informants grow a combination of "improved" and farmers' varieties. Of the farmers' varieties, the most obvious decline and/or loss was reported for wheat varieties. Introduction of improved wheat varieties, pest infestation, shortage of land, low yield performance and climate variability were identified as the principal factors contributing to this loss or decline. Appropriate interventions for future conservation and sustainable use of farmers' varieties were suggested. 相似文献
82.
83.
Bhushan Bharat Singh Brij Pal Saini Kamna Kumari Mamta Tomar Sudhir Kumar Mishra Vijendra 《Environmental Chemistry Letters》2019,17(4):1801-1820
Environmental Chemistry Letters - Microbial cells react with intestinal surfaces and produce enzymes and metabolites that influence human health, host metabolism and immunity. Gut... 相似文献
84.
Neeraj Sharma Kousik Mandal Rajinder Kumar Bipen Kumar Balwinder Singh 《Environmental monitoring and assessment》2014,186(4):2289-2295
Chlorantraniliprole, an anthranilic diamide insecticide with novel mode of action, is found effective against several lepidopteran as well as coleopteran, dipteran, and hemipteran pests. The present studies were carried out to study the persistence pattern of chlorantraniliprole on sugarcane field soil following application of granule formulation. The residues of chlorantraniliprole were estimated using high performance liquid chromatograph (HPLC) and confirmed by liquid chromatograph-mass spectrometry (LC-MS/MS). Following application of chlorantraniliprole (Ferterra 0.4G) at 100 and 200 g a.i. ha?1, the average initial deposits of chlorantraniliprole were observed to be 0.88 and 1.59 mg kg?1, respectively. These residues dissipated below the limit of quantification (LOQ) of 0.01 mg kg?1 after 56 days of the application of insecticides at both the dosages. The half-life values (t 1/2) of chlorantraniliprole were worked out to be 8.36 and 8.25 days, at recommended and double the recommended dosages, respectively. 相似文献
85.
Atul K. Singh Sharad C. Srivastava Pankaj Verma Abubakar Ansari Ambrish Verma 《Environmental monitoring and assessment》2014,186(6):3823-3836
Monitoring of heavy metals was conducted in the Yamuna River considering bioaccumulation factor, exposure concentration, and human health implications which showed contamination levels of copper (Cu), lead (Pb), nickel (Ni), and chromium (Cr) and their dispersion patterns along the river. Largest concentration of Pb in river water was 392 μg L?1; Cu was 392 μg L?1 at the extreme downstream, Allahabad and Ni was 146 μg L?1 at midstream, Agra. Largest concentration of Cu was 617 μg kg?1, Ni 1,621 μg kg?1 at midstream while Pb was 1,214 μg kg?1 at Allahabad in surface sediment. The bioconcentration of Cu, Pb, Ni, and Cr was observed where the largest accumulation of Pb was 2.29 μg kg?1 in Oreochromis niloticus and 1.55 μg kg?1 in Cyprinus carpio invaded at Allahabad while largest concentration of Ni was 174 μg kg?1 in O. niloticus and 124 μg kg?1 in C. carpio in the midstream of the river. The calculated values of hazard index (HI) for Pb was found more than one which indicated human health concern. Carcinogenic risk value for Ni was again high i.e., 17.02?×?10?4 which was larger than all other metals studied. The results of this study indicated bioconcentration in fish due to their exposures to heavy metals from different routes which had human health risk implications. Thus, regular environmental monitoring of heavy metal contamination in fish is advocated for assessing food safety since health risk may be associated with the consumption of fish contaminated through exposure to a degraded environment. 相似文献
86.
87.
Smriti Sharma Balwinder Singh V. K. Gupta 《Environmental monitoring and assessment》2014,186(11):7183-7193
Imidacloprid is extensively used on a broad range of crops worldwide as seed dressing, soil treatment, and foliar application. Hence, the degradation potential of bacterial strains from sugarcane-growing soils was studied in liquid medium for subsequent use in bioremediation of contaminated soils. The microbe cultures degrading imidacloprid were isolated and enriched on Dorn’s broth containing imidacloprid as sole carbon source maintained at 28 °C and Bacillus alkalinitrilicus showed maximum potential to degrade imidacloprid. Clay loam soil samples were fortified with imidacloprid at 50, 100, and 150 mg kg?1 along with 45?×?107 microbe cells under two opposing sets of conditions, viz., autoclaved and unautoclaved. To study degradation and metabolism of imidacloprid under these two conditions, samples were drawn at regular intervals of 7, 14, 28, 35, 42, 49, and 56 days. Among metabolites, three metabolites were detected, viz., 6-chloronicotinic acid, nitrosimine followed by imidacloprid-NTG under both the conditions. Total imidacloprid residues were not found to follow the first-order kinetics in both types of conditions. This paper reports for the first time the potential use of pure cultures of soil-isolated native bacterium B. alkalinitrilicus and also its use along with natural soil microflora for remediation of imidacloprid-contaminated soils. 相似文献
88.
Kumar Gaurav Richa Srivastava Jai Gopal Sharma Ram Singh Vishrut Singh 《International Journal of Green Energy》2016,13(3):320-327
Biodiesel provides a feasible solution to the twin crisis of energy security and environmental concerns prevalent today, and it can be extracted from conventional oil crops as well as microalgae. However, lipid productivity in case of microalgae is much higher and has several advantages as compared with crop plants, so it is a better feedstock for biodiesel. In case of Chlorella pyrenoidosa, the heterotrophic cultured cells were found to be better in terms of lipid production, and ultimately biodiesel production, but the bottleneck is that in this mode glucose is used to feed the cells, which amounts to almost 80% of the total cost of biodiesel production. The purpose of this study is to evaluate and highlight the feasibility of using the industrially cheap cane molasses as a carbon source in place of glucose for a large-scale, low-cost lipid production of Chlorella pyrenoidosa. When treated molasses was used as a carbon source instead of glucose, the biomass sharply increases from 0.89 to 1.22 g L–1. On the other hand, the total lipid content increases from 0.27 to 0.66 g g–1. The specific growth rate and yield was higher in treated molasses as compared with that in glucose-supplemented. A mathematical model was also developed based on logistic, Luedeking–Piret, and Luedeking-Piret-like equations. Model predictions were in satisfactory agreement with the measured data, and the mode of lipid production was growth-associated. 相似文献
89.
Irrigation Water Allocation Using an Inexact Two‐Stage Quadratic Programming with Fuzzy Input under Climate Change 下载免费PDF全文
Mo Li Ping Guo Vijay P. Singh Jie Zhao 《Journal of the American Water Resources Association》2016,52(3):667-684
Agricultural irrigation accounts for nearly 70% of the total water use around the world. Uncertainties and climate change together exacerbate the complexity of optimal allocation of water resources for irrigation. An interval‐fuzzy two‐stage stochastic quadratic programming model is developed for determining the plans for water allocation for irrigation with maximum benefits. The model is shown to be applicable when inputs are expressed as discrete, fuzzy or random. In order to reflect the effect of marginal utility on benefit and cost, the model can also deal with nonlinearities in the objective function. Results from applying the model to a case study in the middle reaches of the Heihe River basin, China, show schemes for water allocation for irrigation of different crops in every month of the crop growth period under various flow levels are effective for achieving high economic benefits. Different climate change scenarios are used to analyze the impact of changing water requirement and water availability on irrigation water allocation. The proposed model can aid the decision maker in formulating desired irrigation water management policies in the wake of uncertainties and changing environment. 相似文献
90.
Chandrasekharan H Sarangi A Nagarajan M Singh VP Rao DU Stalin P Natarajan K Chandrasekaran B Anbazhagan S 《Journal of environmental management》2008,89(1):63-72
In this study, the Tsunami-caused deterioration of soil and groundwater quality in the agricultural fields of coastal Nagapattinam district of Tamilnadu state in India is presented by analyzing their salinity and sodicity parameters. To accomplish this, three sets of soil samples up to a depth of 30cm from the land surface were collected for the first six months of the year 2005 from 28 locations and the ground water samples were monitored from seven existing dug wells and hand pumps covering the study region at intervals of 3 months. The EC and pH values of both the soil and ground water samples were estimated and the spatial and temporal variability mappings of these parameters were performed using the geostatistical analysis module of ArcGIS((R)). It was observed that the spherical semivariogram fitted well with the data set of both EC and pH and the generated kriged maps explained the spatial and temporal variability under different ranges of EC and pH values. Further, the recorded EC and pH data of soil and ground water during pre-Tsunami periods were compared with the collected data and generated variability soil maps of EC and pH of the post-Tsunami period. It was revealed from this analysis that the soil quality six months after the Tsunami was nearing the pre-Tsunami scenario (EC< 1.5dSm(-1); pH<8), whereas the quality of ground water remained highly saline and unfit for irrigation and drinking. These observations were compared with the ground scenarios of the study region and possible causes for such changes and the remedial measures for taking up regular agricultural practices are also discussed. 相似文献