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991.
Fish‐Net: Probabilistic models for fishway planning,design and monitoring to support environmentally sustainable hydropower
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Martin Wilkes Lee Baumgartner Craig Boys Luiz G M Silva Justin O'Connor Matthew Jones Ivor Stuart Evelyn Habit Oscar Link J Angus Webb 《Fish and Fisheries》2018,19(4):677-697
The construction of fishways for upstream and downstream connectivity is the preferred mitigation measure for hydropower dams and other riverine barriers. Yet empirical evidence for effective design criteria for many species is missing. We therefore assembled a group of international fishway designers and combined their knowledge with available empirical data using a formal expert elicitation protocol and Bayesian networks. The expert elicitation method we use minimizes biases typically associated with such approaches. Demonstrating our application with a case‐study on the temperate Southern Hemisphere, we use the resulting probabilistic models to predict the following, given alternative design parameters: (i) the effectiveness of technical fishways for upstream movement of migratory fish; (ii) habitat quality in nature‐like bypasses for resident fish; and (iii) rates of mortality during downstream passage of all fish through turbines and spillways. The Fish Passage Network (Fish‐Net) predicts that fishways for native species could be near 0% or near 100% efficient depending on their design, suggesting great scope for adequate mitigation. Sensitivity analyses revealed the most important parameters as follows: (i) design of attraction and entrance features of technical fishways for upstream migration; (ii) habitat preferences of resident fish in nature‐like bypasses; and (iii) susceptibility of fish to barotrauma and blade strike during turbine passage. Numerical modelling predicted that mortality rates of small‐bodied fish (50–100 mm TL) due to blade strike may be higher for Kaplan than Francis turbines. Our findings can be used to support environmentally sustainable decisions in the planning, design and monitoring stages of hydropower development. 相似文献
992.
Jos Fernando M. Gonalves Mariana Hinzmann Jorge Machado Sandra Arajo Jos Carlos Oliveira Rodrigo O. A. Ozrio 《International Aquatic Research》2018,10(2):133-143
l-Carnitine plays a key role in the regulation of energy metabolism and growth in fish. The aim of this study was to determine the effects of dietary l-carnitine levels on carnitine homeostasis and energy metabolism in diploid and triploid trout (Oncorhynchus mykiss). Diploid and triploid trout (29.5 ± 0.6 and 31.8 ± 0.5 g, respectively) were fed with three diets supplemented with 15, 200 or 530 mg l-carnitine/kg, respectively, for 56 days. Compared to 15 mg l-carnitine, total carnitine content increased in the liver by 182% in diploid and by 154% in triploid trout fed 530 mg l-carnitine. In muscle, total carnitine content increased by 60 and 73% in diploid and by 34 and 75% in triploid with the increase in dietary l-carnitine levels. l-Carnitine caused no significant change in the plasma concentrations of metabolites like proteins (ammonia, urea and protein), lipid (triglycerides), carbohydrate (glucose, lactate) and enzyme activities (lipase, lactate, alanine transaminase, lactic acid dehydrogenase). Triploid trout had significantly lower plasma ammonia (P = 0.003), lipase (P = 0.005) and triiodothyronine (T3; P = 0.003) levels than diploid trout. In conclusion, ploidy significantly affected the energy metabolism in rainbow trout, dietary l-carnitine levels altered the l-carnitine homeostasis, but not influence nutritional metabolism. 相似文献
993.
994.
R. A. Silva L. Zambolim I. S. L. Castro H. S. Rodrigues C. D. Cruz E. T. Caixeta 《Euphytica》2018,214(9):153
The main phytosanitary problems affecting global coffee production are the fungal diseases known as rust, caused by Hemileia vastatrix Berkeley and Broome, and coffee berry disease (CBD), induced by Colletotrichum kahawae Waller and Bridge. The main disease control strategy is the use of resistant coffee cultivars. Híbrido de Timor is the most important source of resistant varieties used in breeding programs worldwide. The objective of this work was to characterize the diversity and disease resistance of 152 HdT genotypes from the germplasm collection at the Universidade Federal de Viçosa (UFV). Accessions were phenotyped with H. vastatrix races II and XXXIII. Molecular analysis was carried out with 29 random microsatellite markers or single sequence repeats (SSRs), and two SSRs associated with the CBD resistance gene Ck-1. All accessions in the germplasm collection were resistant to H. vastatrix race II, and 141 were resistant to H. vastatrix race XXXIII. Based on the presence of markers, there were 106 accessions containing the CBD resistance gene Ck-1. In the diversity study, the 152 accessions clustered into 21 different groups. A unique molecular profile (fingerprint) was determined for each individual, using 52 alleles from 22 SSR markers. The HdT germplasm of UFV was highly diverse, and included 99 accessions with multiple disease resistance genes, including the CBD resistance gene Ck-1, and others conferring resistance to H. vastatrix races II and XXXIII. 相似文献
995.
Predatory beetles in cacao agroforestry systems in Brazilian Atlantic forest: a test of the natural enemy hypothesis 总被引:1,自引:0,他引:1
The natural enemy hypothesis predicts a positive correlation between plant species diversity and natural enemy control. This study aimed to evaluate the role of traditional cacao agroforests, known as “cabrucas,” on the conservation of the predatory beetle community compared to that of monodominant rubber agroforests. Predatory beetles were sampled in three habitats in Southeastern Bahia, Brazil: cabrucas and rubber agroforests and native Atlantic forests. In each habitat, 18 10 m2 plots were established, in which canopy cover was measured and beetles were sampled with a modified Malaise/window trap. Land use intensification did not affect the composition of predatory beetles, with the presence of widely distributed species that are also capable of colonizing simpler environments such as the rubber agroforest. Canopy cover had a positive effect on generalist predator diversity and we observed a reduction in the abundance and species richness of generalist predators with increasing habitat homogenization. Despite the simplified structure of the habitat, the remaining tree diversity and canopy cover in cabrucas supported a community of generalist predators similar to the one found in the native forest. Species diversity of bark beetle predators was higher in cabrucas, which may be due to the high diversity of bark beetles and the favorable abiotic conditions, whereas the low abundance of prey in the native forest and severe abiotic conditions in the rubber agroforest probably determined the lower diversity of generalist predators in these habitats. Cabrucas play an important role in the conservation, supporting a community of predatory beetles more similar to the one found in native forest and that is more effective at controlling populations of herbivores than in homogeneous rubber agroforests. 相似文献
996.
Episcleral cyclosporine A implants for the management of unilateral keratoconjunctivitis sicca in an 8‐year‐old mare
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Catriona J. Mackenzie Harry B. Carslake Matthew Robin Rebecca J. Kent Fernando Malalana 《Veterinary ophthalmology》2017,20(1):79-83
An 8‐year‐old mare was presented for investigation of a 1‐month history of blepharospasm, eyelid swelling, corneal edema, and ocular discharge of the right eye (OD). Ophthalmic examination confirmed mucopurulent ocular discharge, conjunctival hyperemia, and a dry, dull appearance to the cornea OD. Schirmer tear test results confirmed an absence of tear production OD (0 mm/min) consistent with keratoconjunctivitis sicca. Treatment with topical 0.2% cyclosporine A resulted in an improvement in clinical signs. An episcleral cyclosporine A implant was placed under standing sedation 5 days after initial presentation. Re‐examination 9 days post‐operatively confirmed that the mare's tear production in the right eye had improved and no further clinical signs had been observed. Topical medications were gradually discontinued. Re‐examinations performed up to 12 months postsurgery showed no recurrence of clinical signs and no adverse effects of the implant. To our knowledge, this is the first report of the use of a cyclosporine A implant in the management of KCS in a horse and highlights its potential as an effective, alternative therapy in the management of KCS in horses. 相似文献
997.
Characterization of a novel form of progressive retinal atrophy in Whippet dogs: a clinical,electroretinographic, and breeding study
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998.
João Carvalho Óscar Cardoso Mário Costa Abel Rodrigues 《European Journal of Forest Research》2017,136(1):185-192
This work presents the results of a study on the variation of the chemical composition of Pyrenean oak (Quercus pyrenaica Willd.) heartwood among different sites and its relationship with the soil chemical characteristics. The chemical characteristics of the heartwood are quantified in terms of proximate and ultimate analysis, calorific value and ash composition. Subsequently, the relationship between the wood chemical characteristics and the soil characteristics was also examined. The results showed no significant differences between the wood chemical characteristics from different sites. There are, however, significant differences between trees from the same site regarding the wood ash content, the calorific value and the contents of nitrogen and hydrogen. Strong correlations were observed between the heartwood ash contents of BaO, MnO, CuO and TiO2 and the soil nitrogen, phosphorous and potassium and the soil exchangeable base contents. 相似文献
999.
Franslley Morona Fábio Luiz Melquíades Marcelo Marques Lopes Muller 《Communications in Soil Science and Plant Analysis》2017,48(19):2288-2293
The organic matter (OM) quantity in soils is of fundamental importance for agriculture. The indirect determination of the OM through the Total Organic Carbon (TOC) quantity is performed by most soil laboratories in Brazil using the Walkley–Black (WB) method. This procedure involves oxidation with potassium dichromate which is a cancerous reagent. The objective of this study is to optimize the parameters for OM determination by the gravimetric method and to estimate the van Bemmelen factor for the studied soil. The studied region is the second and third plateau of Parana State, Brazil, from which 50 agricultural soil samples were analyzed. The temperature and exposition time in muffle were determined after a thermal analysis. The optimized parameters for the gravimetric method were 3 h at 420°C in the muffle furnace. The results for WB and gravimetric methods presented a good correlation and the van Bemmelen factor for the studied soil was 4.37. 相似文献
1000.
Marcus Vinicius Freire Andrade Isabel Kimiko Sakamoto Aline Gomes de Oliveira Paranhos Edson Luiz Silva Maria Bernadete Amâncio Varesche 《Water, air, and soil pollution》2017,228(4):165
Effects of ethanol and nitrate on linear alkyl benzene sulfonate (LAS) degradation were investigated using central composite design. At experimental design, removal of 99.9% was observed in batch reactors (1 L) with 9.8 to 41.2 mg L?1 of LAS. The batch reactors were kept under agitation at 120 rpm and 30 °C. Ethanol (co-substrate) and nitrate (electron acceptor) were statistically significant factors (p?<?0.05) in surfactant removal. Optimal values were 97.5 and 88 mg L?1 for ethanol and nitrate, respectively. LAS removal was kinetically investigated by varying surfactant concentration while using optimal values. Batch I (27 mg L?1 LAS) exhibited greater degradation rate (KLAS) (0.054 h?1) in the presence of ethanol and nitrate. Nonetheless, in Batch II (60 mg L?1 LAS), the KLAS values decreased in those reactors probably due to inhibition by excess substrate for same concentrations of nitrate and ethanol added in reactors. As LAS concentration increased, the dominance of bacterial populations also increased, whereas diversity index decreased from 2.8 (inoculum) to 2.4 and 2.5 for reactors with both added nitrate and ethanol and those with only added ethanol, respectively. Probably, a selection of microbial populations occurred in relation to LAS concentration. The nitrate and ethanol, at able concentration, made it possible the induction of denitrifying microrganisms foward to LAS removal. 相似文献