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961.
Feniova I. Yu. Razlutskij V. I. Gladyshev M. I. Kostrzewska-Szlakowska I. Majsak N. N. Rzepecki M. Sushchik N. N. Zilitinkevich N. S. 《Russian Journal of Ecology》2019,50(1):50-57
Russian Journal of Ecology - It has been shown that the main drivers of the dynamics of cladoceran and copepod abundances can be predators (fish), the quantity and/or quality of food in terms of... 相似文献
962.
Russian Journal of Ecology - Temporal and spatial variations of phytoplankton community in Lake Erhai were investigated from May 2010 to April 2011. A total of 124 species belonging to 8 phyla and... 相似文献
963.
Kuselah Mae M. Tayaban Katherine L. Pintor Pierangeli G. Vital 《Environment, Development and Sustainability》2018,20(3):1311-1328
Prawn aquaculture industry is one of the developing economic activities in the Philippines. Generally, a wide range of microalgae typically grow and proliferate in many aquaculture ponds. However, certain species of microalgae have the ability to form harmful algal blooms (HABs) which often bring damaging consequences to the aquaculture industry, food safety, and the environment. The study aims to identify and characterize the composition of microalgae (particularly Cyanophyta) that are capable of forming HABs in selected freshwater prawn culture ponds in Central Luzon, Philippines, using morphological, ultrastructural, and molecular characterizations. From water samples collected in ten selected ponds across Central Luzon (Bulacan, Nueva Ecija, Pampanga, Tarlac, and Zambales), potential HAB formers such as Oscillatoria agardhii, O. princeps, Microcystis aeruginosa, and M. wesenbergii were observed to have occurred mostly, while Anabaena circinalis was only observed in one site. Both morphological and ultrastructural methods brought upon some challenges and limitations while molecular methods using 16S rRNA gene and phylogenetic analysis which were optimized in this study offered better and more efficient ways of identification and were helpful in resolving genus-level and species-level relationships. The influence of physicochemical properties of pond water, especially nutrient levels (nitrate, nitrite, and orthophosphate) on the occurrence of these cyanobacteria was also analyzed. As a pioneering study on freshwater HABs in aquaculture ponds in the country, results of the study can provide information to improve the knowledge in bloom occurrence and prediction, and to develop freshwater HAB prevention and control methods. 相似文献
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The manufacturing industry produces a lot of different by-products and waste. In this research, the utilization of different industrial wastes as a part of wood-plastic composites was tested. Limestone waste and carton cutting waste were tested by replacing part of the reinforcing fibers of the composite with these materials. The materials were made with the extrusion process, and they were tested for their mechanical properties, water absorption and thickness swelling. The materials were also viewed with a scanning electron microscope. The results showed that both industrial wastes affected the properties of the composite. Mining waste in the composite improved the moisture properties, impact strength and hardness of the material. Carton cutting waste improved the impact strength remarkably. 相似文献
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Vah Mélanie Jarno Armelle Le Bot Sophie Ferret Yann Marin François 《Environmental Fluid Mechanics》2020,20(4):1031-1052
Environmental Fluid Mechanics - Most studies on sediment transport and bedforms migration consider unlimited sediment supply conditions. However, areas where the sediment supply is limited are... 相似文献
970.
Tohamy Hossam G. Gad El-Karim Dina R. El-Sayed Yasser S. 《Environmental science and pollution research international》2019,26(21):21524-21534
Environmental Science and Pollution Research - Hydroxyurea (HDU), a class of antineoplastic drugs, has a powerful efficacy in the treatment of several types of malignancies. However, it has... 相似文献