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31.
Rafael?R.?Cantú Celso?AitaEmail author Alexandre?Doneda Diego?A.?Giacomini Alexandre?Dessbesell Marlon?Arenhardt Géssica?G.?De Bastiani Stefen?B.?Pujol Philippe?Rochette Martin?H.?Chantigny Sandro?J.?Giacomini 《Biology and Fertility of Soils》2017,53(6):589-599
Alternative fertilization practices are needed for reducing gaseous and leaching N losses at high urea application rates. The objective of this study was to compare gaseous N emissions (N2O and NH3) and NO3 ? concentrations in the soil solution during two successive lettuce cropping seasons under contrasting fertilization practices. Treatments were fertilization with regular urea (U), urea treated with urease [N-(n-butyl) thiophosphoric triamide (NBPT)] and nitrification [dicyandiamide (DCD)] inhibitors (UIs), non-acidified pig slurry compost (PSC), acidified pig slurry compost (APSC), and an unfertilized control (C). Acidification of pig slurry during composting had no impact on soil cumulative N2O emissions during the cropping seasons. The use of composts resulted in emission factors (EFs) (PSC, 0.09% of applied N; APSC, 0.16%) an order of magnitude smaller than with regular urea (1.63%). Similarly, adding NBPT and DCD to urea reduced the N2O EF from 1.63 to 0.37% of applied N and fertilizer-induced NH3 emissions from 30.2 to 3.4% of applied N. Composts and UI resulted in yield-scaled N2O emissions that were 33 to 49% lower than the unfertilized control and 64 to 73% lower than the regular urea estimates, indicating a greater efficiency of supplied N with composts and UI. Nitrate concentration of the soil solution (at 0.1 and 0.3 m) in PSC, APSC, and UI plots was similar to the control and up to 17 times lower than with regular urea, indicating reduced risks for leaching losses. We conclude that, as compared to regular urea, the use of composted pig slurry, with and without acidification, and the addition of NBPT and DCD inhibitors to urea are good practices to reduce environmental N losses from lettuce production under sub-tropical climate. 相似文献
32.
Andréia Peiter Tanna E. R. Fiuza Roberto de Matos Augusto Celso Antunes Sandra Regina Masetto Antunes Cleber A. Lindino 《Water, air, and soil pollution》2017,228(3):114
To meet demand for processes that minimize the environmental impact generated by waste, efficient systems that degrade such substances and use them as an alternative source for renewable energy generation are increasingly becoming needed. Increased food production to meet the needs of the world’s increasing population has encouraged the use of agrochemicals in order to ensure productivity in crops. However, excessive use of pesticides has caused contamination of natural systems and, therefore, of living beings. In this context, this work presents an alternative plan for an integrated system that simultaneously remediates contaminated environments and generates electricity using a Cu/CuO electrode as a photocatalyst. The materials were prepared from reagents and accessible metals, which reduced costs and contributed to a clean process, without using organic additives. The results showed that the generation of current in an area 6.9 cm2 was 193.37 μA for potassium hydrogen phthalate degradation. The Aminol 806® and Connect® pesticides were degraded by 54.46 and 21.02%, respectively, after 90 min in the system, under ultraviolet radiation. The results showed that, at pH 2.0, the generation of current was 2493.2 mA (36.165 mA m?2) for Aminol 806® and 7.894 mA (0.114 mA m?2) for Connect®. The degradation of organic contaminants and simultaneous power generation of energy in the integrated system provides a self-sustaining form of environmental remediation and energy recovery, and its use is possible on a large scale. 相似文献
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34.
Britto Pedro Caldas Jaeger Dirk Hoffmann Stephan Robert Renato Cesar Gonalves Vibrans Alexander Christian Fantini Alfredo Celso 《European Journal of Forest Research》2022,141(4):665-681
European Journal of Forest Research - Subject to overexploitation in the past centuries, the Atlantic Forest is subject to very rigorous protection rules. However, the law is a controversial issue... 相似文献
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Jatobá A Vieira Fdo N Buglione-Neto CC Mouriño' JL Silva BC Seiftter WQ Andreatta ER 《Fish physiology and biochemistry》2011,37(4):725-732
The aim of this study was to assess the effect of a probiotic (Lactobacillus
plantarum) supplemented diet on Nile tilapia (Oreochromis
niloticus) in a polyculture system with marine shrimp (Litopenaeus vannamei) as regards culture performance, hematology, and gut bacterial microbiota. Ten 20-m2 pens were arranged in one earthen pond
and stocked with 2 fish (41.9 g) m−2 and 10 shrimp (2.3 g) m−2, in total of 40 Nile tilapias and 200 shrimp per experimental unit. Tilapia groups in five of the experimental units were
fed a commercial diet supplemented with L. plantarum and the other five with an unsupplemented commercial diet (control). After 12 weeks of culture, the tilapia groups fed the
probiotic-supplemented diet presented values 13.6, 7.5, and 7.1% higher for feed efficiency, yield, and final weight, respectively.
Viable culturable heterotrophic bacteria counts were reduced, and the number of lactic acid bacteria was increased in the
gut of fish and shrimp fed the probiotic-supplemented diet. Hematological analyses showed higher number of thrombocytes and
leukocytes in tilapia fed the supplemented diet. L. plantarum utilized in this study colonized the gut of tilapia and shrimp and resulted in reduced number of total bacteria and increased
tilapia final weight and feed efficiency. 相似文献
39.
Gustavo José Braga Allan Kardec Braga Ramos Marcelo Ayres Carvalho Carlos Eduardo Lazarini Fonseca Francisco Duarte Fernandes Celso Dornellas Fernandes 《Grass and Forage Science》2020,75(2):206-215
The use of stylosanthes in mixed grass-legume pastures may minimize the decline in forage quality and quantity that occurs in monoculture grass pastures, even though the availability of commercial cultivars in Brazil is still limited. The objective of the study was to evaluate the liveweight (LW) gain of young Nellore bulls in a mixed pasture of Brachiaria brizantha (cv. Paiaguás) with the latest release Stylosanthes guianensis cv. Bela. The study was conducted in Planaltina, FD, Brazil, from September to August in two consecutive years, right after seeding. The experimental design was a randomized complete block design with two treatments (mixed or monoculture Paiaguás pastures) and three replicates. The average daily gain (ADG) was on average greater in mixed pastures (0.436 vs. 0.350 kg head−1 day−1 in mixed and grass pastures respectively), particularly in the dry period (0.344 vs. 0.183 kg head−1 day−1). The benefit of mixed over monoculture grass pastures throughout the year was 22 kg LW/head and 55 kg LW/ha. The presence of stylosanthes increased the crude protein (CP) concentration in mixed pastures (120 g/kg) when compared to monoculture grass pastures (109 g/kg), probably influencing the ADG of bulls. The increase of liveweight gain, predominantly in the dry season, makes the high-protein stylosanthes cv. Bela an alternative to buffer the seasonal deficit of forage quality in newly seeded grass pastures. 相似文献
40.
Segenet Kelemu Daniel Z. Skinner Jorge L. Badel Claudia X. Moreno María X. Rodríguez Celso D. Fernandes María J. Charchar Sukumar Chakraborty 《European journal of plant pathology / European Foundation for Plant Pathology》1999,105(3):261-272
The degree of genetic diversity of 127 Colletotrichum gloeosporioides isolates from Stylosanthes guianensis genotypes in South America was measured at the molecular level by random amplified polymorphic DNA (RAPD) with nine arbitrary primers of 10 bases, and by restriction fragment length polymorphism (RFLP) with a non-LTR (long terminal repeats) retrotransposon DNA sequence. The RAPD products revealed scorable polymorphism among the isolates, and a total of 80 band positions were scored. Sixty-three of the 127 isolates were clustered into 13 distinct lineages usually correlating with geographic origin. Where isolates from various regions were clustered together, most had identical host genotype origin. The pathogen population sampled from Carimagua, Colombia, a long-time Stylosanthes breeding and selection site, with a savanna ecosystem, was highly diverse. A set of 12 S. guianensis genotype differentials was used to characterize pathogenic variability of 104 isolates and their virulence patterns were grouped into 57 pathotypes. However, when they were tested on four Australian differentials, they grouped into 11 pathotypes. As shown in previous studies, no strict correlations existed between genetic diversity measured by RAPD or RFLP, and pathotype defined by pathogenicity pattern on the differentials. Southern blot analysis of the 127 isolates revealed 23 hybridizing fragments, resulting in 41 fingerprint patterns among the 127 isolates. Relationships between RFLP and RAPD variables were examined using Spearman's Rank Correlation Coefficient, which showed that the two measures of genotypic variation are in agreement. 相似文献