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Journal of Polymers and the Environment - The present investigation aimed at developing core–shell structured partially etherified fenugreek seed mucilage (EFSM)-sodium alginate (SA) based... 相似文献
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Conservation efforts are often motivated by the threat of global extinction. Yet if conservationists had more information suggesting that extirpation of individual species could lead to undesirable ecological effects, they might more frequently attempt to protect or restore such species across their ranges even if they were not globally endangered. Scientists have seldom measured or quantitatively predicted the functional consequences of species loss, even for large, extinction‐prone species that theory suggests should be functionally unique. We measured the contribution of Asian elephants (Elephas maximus) to the dispersal of 3 large‐fruited species in a disturbed tropical moist forest and predicted the extent to which alternative dispersers could compensate for elephants in their absence. We created an empirical probability model with data on frugivory and seed dispersal from Buxa Tiger Reserve, India. These data were used to estimate the proportion of seeds consumed by elephants and other frugivores that survive handling and density‐dependent processes (Janzen‐Connell effects and conspecific intradung competition) and germinate. Without compensation, the number of seeds dispersed and surviving density‐dependent effects decreased 26% (Artocarpus chaplasha), 42% (Careya arborea), and 72% (Dillenia indica) when elephants were absent from the ecosystem. Compensatory fruit removal by other animals substantially ameliorated these losses. For instance, reductions in successful dispersal of D. indica were as low as 23% when gaur (Bos gaurus) persisted, but median dispersal distance still declined from 30% (C. arborea) to 90% (A. chaplasha) without elephants. Our results support the theory that the largest animal species in an ecosystem have nonredundant ecological functionality and that their extirpation is likely to lead to the deterioration of ecosystem processes such as seed dispersal. This effect is likely accentuated by the overall defaunation of many tropical systems. 相似文献
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This paper, reports for the first time, an extensive study of alpha activity of all widely used building materials (plaster of Paris, stone chips, marble, white cement, mosaic stone, limestone, sand, granite, cement brick, asbestos, red brick, cement tile, ceramic tile and ceramics) in West Bengal, India. The alpha activities have been measured using Solid State Nuclear Track Detector (SSNTD), a very sensitive detector for alpha particles. The samples were collected from local markets of Kolkata. The measured average alpha activities ranged from 22.7+/-2.5 to 590.6+/-16.8Bqkg(-1). The alpha activity of ceramic tiles was highest and provides additional data to estimate the effect of environmental radiation exposure on human health. 相似文献
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Bindhu SJ Bera AK 《Journal of environmental biology / Academy of Environmental Biology, India》2001,22(4):307-309
Effect of different concentrations of CdSO4 (10(-4) M, 5 x 10(-4) M and 10(-3) M) on leaf area, stomatal frequency, stomatal index and pigment content in 6 days old mungbean seedlings was studied under laboratory conditions. Except at 10(-4) M CdSO4, leaf area decreased with an increase in the concentration of CdSO4. Stomatal frequency on the leaf surface increased at 5 x 10(-4) M and 10(-3) M CdSO4 in comparison to untreated control. However, reverse was the case for stomatal index. Chlorophyll-a, chlorophyll-b, total chlorophyll, and chlorophyll a/b ratio were increased at 10(-4) M CdSO4, and decreased thereafter with an increase in the concentration of Cd2+. Possible reasons for the stimulatory effect at low concentrations and inhibitory effect with higher concentrations are discussed. 相似文献
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Chowdhury Puja Mukhopadhyay Bhabani Prasad Nayak Siperna Bera Amit 《Environment, Development and Sustainability》2022,24(9):11320-11347
Environment, Development and Sustainability - Purulia is a hard rock terrain where water scarcity as well as water quality degradation has been a major threat for the past few decades. The prolong... 相似文献
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Bera Tanushree Kumar Vikash Sarkar Dhruba Jyoti Devi Manoharmayum Shaya Behera Bijay Kumar Das Basanta Kumar 《Environmental science and pollution research international》2022,29(45):67801-67820
Environmental Science and Pollution Research - East Kolkata Wetland (EKW) is one of the largest sewage-fed wetlands in the world, which support the livelihood of thousands of peoples. However, at... 相似文献