Soil organic carbon fractions and humic substances are affected by land uses of Caatinga forest in Brazil     

Uemeson José dos Santos  Gustavo Pereira Duda  Marise Conceição Marques  José Romualdo de Sousa Lima  Eduardo Soares de Souza 《Arid Land Research and Management》2019,33(3):255-273

Caatinga is a Brazilian dry ecosystem that occupies around 1 million km² and is one of the largest tropical dry forests of the world. About 46% of the area that was originally covered has been deforested. Land use can cause pronounced reduction in soil carbon stocks that play a major role in the global carbon cycle. The objective of this study was to improve our understanding of the effect of land use on oxidizable carbon fractions, total carbon stocks and humic substances in different layers of soil in a Brazilian semi-arid region. We analyzed soils from tropical dry forest (TDF), forest succession with Anadenanthera falcata (ANA), with Tabebuia alba (TAB), secondary scrubby regeneration (SCR), and non-irrigated maize (MS). Forests showed larger fractions of more labile carbon, except for TDF. The most recalcitrant fraction of carbon stock, humin fraction stock, with the different land use decreased by 38–53% compared to TDF. Oxidizable carbon fractions, carbon stocks, and humic fraction stocks were able to differentiate the successional land uses and agricultural cover from TDF, mainly in the 0–5?cm layer. Our results show that changes in land use, especially with ANA forest succession, showed a larger labile carbon fraction, indicating easy decomposition and loss. Our results provide an alternative tool for the management of deforested areas in tropical dry caatinga ecosystems. This would contribute to the conservation of dry forest systems and could serve as guideline for sustainable management of agriculturally impacted caatinga areas.  相似文献   

Effect of the conservation procedure on the contents of phenolic compounds and organic acids in chanterelle (Cantharellus cibarius) mushroom     

Valentão P  Andrade PB  Rangel J  Ribeiro B  Silva BM  Baptista P  Seabra RM 《Journal of agricultural and food chemistry》2005,53(12):4925-4931

To check the influence of the conservation procedure in the chemical composition of chanterelle mushroom, phenolic compounds and organic acids of samples preserved under four different conditions (drying, freezing, conservation in olive oil and in vinegar) were determined. Phenolics and organic acids were analyzed by HPLC-DAD and HPLC-UV, respectively. The results showed that chanterelle is characterized by the presence of six phenolic compounds (3-, 4-, and 5-O-caffeoylquinic acid, caffeic acid, p-coumaric acid, and rutin) and five organic acids (citric, ascorbic, malic, shikimic, and fumaric acids). Samples preserved in olive oil also exhibited hydroxytyrosol, tyrosol, luteolin, and apigenin, whereas conservation in vinegar led to the detection of hydroxytyrosol, tyrosol, and tartaric acid in the analyzed samples. The conservation procedures to which chanterelle samples were subjected seem to affect the qualitative and quantitative phenolics and organic acids profiles.  相似文献   

Microbial HemG‐type protoporphyrinogen IX oxidase enzymes for biotechnology applications in plant herbicide tolerance traits     

Clayton T Larue  Joel E Ream  Xuefeng Zhou  Farhard Moshiri  Arlene Howe  Michael Goley  Oscar C Sparks  Steven T Voss  Erin Hall  Christine Ellis  Janice Weihe  Qungang Qi  Daniela Ribeiro  Xiaoping Wei  Shirley Guo  Artem G Evdokimov  Marguerite J Varagona  James K Roberts 《Pest management science》2020,76(3):1031-1038

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Volatile emissions of watercress (Nasturtium officinale) leaves and passion fruit (Passiflora edulis) seeds against Meloidogyne incognita     

Marcela F Silva  Vicente P Campos  Aline F Barros  Willian C Terra  Mrcio P Pedroso  Vanessa A Gomes  Clerio R Ribeiro  Fabíola J Silva 《Pest management science》2020,76(4):1413-1421

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Effects of shrimp pond water on phytoplankton: importance of salinity and trophic status of the receiving environment     

Alessandro Pereira Cardozo  Clarisse Odebrecht 《Aquaculture Research》2014,45(10):1600-1610

Aquaculture generates a large load of effluents rich in organic matter and nutrients that may be introduced into the environment. This study aimed to assess in a microcosm experiment, the effect of shrimp pond water mixed with Patos Lagoon estuary water on phytoplankton chlorophyll a and primary production, simulating two salinities. Chlorophyll a, dissolved inorganic nutrients and primary production were measured in two experiments. In Harvest I, salinity of shrimp pond and environment water was similar, and chlorophyll a showed different trends over time, according to the amount of nitrogen available. In Harvest II, with different salinities and high nutrient concentrations in environment water, chlorophyll a levels showed a similar increasing trend over time in all mixtures. Net primary production showed differences among treatments in the first sampling in Harvest I, but not in the second, whereas no differences were observed among treatments in Harvest II. We conclude that shrimp pond effluent can lead to short‐term variations in chlorophyll a and primary production levels, with similar salinities. Salinity differences result in lower chlorophyll a and primary production values than expected according to the nutrient input. Differences in salinity can be an important management strategy to choose the best harvest period.  相似文献   

Dynamics and efficacy of sulfentrazone,flumioxazin, and isoxaflutole herbicides applied on eucalyptus harvest residues     

Carbonari  Caio Antonio  Gomes  Giovanna Larissa Gimenes Cotrick  Krenchinski  Fábio Henrique  Simões  Plinio Saulo  Batista de Castro  Edicarlos  Velini  Edivaldo Domingues 《New Forests》2020,51(4):723-737

New Forests - Eucalyptus harvests generate residues that remain on the soil and affect the efficacy of preemergent herbicides in the following planting cycle. The objective of this work was to...  相似文献   

Limnology of Macrobrachium amazonicum grow‐out ponds subject to high inflow of nutrient‐rich water and different stocking and harvest management     

Janaina Mitsue Kimpara  Fabricio Ribeiro Tito Rosa  Bruno de Lima Preto  Wagner C Valenti 《Aquaculture Research》2011,42(9):1289-1297

We evaluated the water characteristics and particle sedimentation in Macrobrachium amazonicum (Heller 1862) grow‐out ponds supplied with a high inflow of nutrient‐rich water. Prawns were subject to different stocking and harvesting strategies: upper‐graded juveniles, lower‐graded juveniles, non‐graded juveniles+selective harvesting and traditional farming (non‐grading juveniles and total harvest only). Dissolved oxygen, afternoon N‐ammonia and N‐nitrate and soluble orthophosphate were lower in the ponds in comparison with inflow water through the rearing cycle. Ponds stocked with the upper population fraction of graded prawns showed higher turbidity, total suspended solids and total Kjeldahl nitrogen than the remaining treatments. An increase in the chemical oxygen demand:biochemical oxygen demand ratio from inlet (4.9) to pond (7.1–8.0) waters indicated a non‐readily biodegradable fraction enhancement in ponds. The sedimentation mean rate ranged from 0.08 to 0.16 mm day^?1 and sediment contained >80% of organic matter. The major factors affecting pond ecosystem dynamic were the organic load (due to primary production and feed addition) and bioturbation caused by stocking larger animals. Data suggest that M. amazonicum grow‐out in ponds subjected to a high inflow of nutrient‐rich water produce changes in the water properties, huge accumulation of organic sediment at the pond bottom and non‐readily biodegradable material in the water column. However, the water quality remains suitable for aquaculture purposes. Therefore, nutrient‐rich waters, when available, may represent a source of unpaid nutrients, which may be incorporated into economically valued biomass if managed properly.  相似文献   

Associations between morphometric variables and weight and yields carcass in Pirapitinga Piaractus brachypomus     

Fagner Machado Ribeiro  Mrio Lima  Pedro Aurlio Tataíra da Costa  Diego Machado Pereira  Thony Assis Carvalho  Tadeu Vilela de Souza  Hortência Aparecida Botelho  Fabyano Fonseca e Silva  Adriano Carvalho Costa 《Aquaculture Research》2019,50(7):2004-2011

The objective of this work was to evaluate the association between morphometric variables and carcass characteristics in Pirapitinga. We used a thousand specimens of Pirapitinga with an average weight of 1,200 g, which were stunned, slaughtered, weighed, measured, and processed for morphometric and processing yield analysis, to obtain weights, carcass and fillet yields. Initially, the linearity of the variables was verified. Pearson's simple and partial correlation tests were performed between all metrics. Track analysis was performed considering the weights and yields of carcass and filet as dependent variables and the others as independent variables. Ridge regression models were used to eliminate the effects of multicollinearity among the independent variables. Observations showed that the simple correlations between body weights and yields were superior to the partial ones in terms of magnitude. The length and circumference of the specimens were the measures most linearly associated with weight, carcass weight and fillet with rib weight. As for carcass yield and fillet yield, linear correlation coefficients were low and not significant when associated with body weights. With the path analysis, we could observe significant positive correlations between the morphometric measurements for weight, carcass weight and fillet with rib weight. The standard length, body circumference and body circumference/body height ratio are the most correlated. The latter are the most important variables in the evaluation of body weights in Pirapitinga fish. They can serve as criteria for indirect selection in searching for fish with better carcass characteristics. As for fillet and carcass yields, the morphometric variables have not shown to be efficient for indirect selection.  相似文献   

Hepatozoon canis infection associated with dog ticks of rural areas of Rio de Janeiro State, Brazil     

O'Dwyer LH  Massard CL  Pereira de Souza JC 《Veterinary parasitology》2001,94(3):143-150

Hepatozoon canis is a tick-borne protozoan that infects dogs and has been reported throughout the world. Manifestation of H. canis infection varies from being sub-clinical in apparently healthy dogs to severe illness. The main vector of the infection is the dog tick, Rhipicephalus sanguineus although other species may also transmit this agent. H. canis has been reported previously in Brazil, but mostly as an occasional finding during laboratory exams and always associated with other diseases. The prevalence of H. canis in dogs of rural areas of Brazil has been little studied. For this study, 250 dogs from seven counties of Rio de Janeiro state were examined. All the dogs were from rural areas, near forest. Of the dogs examined, 26 dogs were from Seropédica, 82 from Itaguaí, 41 from Paracambi, 26 from Mangaratiba, 32 from Barra do Piraí, 32 from Piraí and 11 from Miguel Pereira. Blood smears from the peripheral blood of the ear were taken and ticks found on the dogs were collected for identification in the laboratory. Using blood smear evaluation, H. canis was identified in 39.2% of the animals examined. Other hemoparasites identified were Babesia canis (5.2%) and Ehrlichia canis (4.8%). Four tick species were found parasitizing the dogs: Amblyomma cajennense (23.6%), R. sanguineus (12.4%), Amblyomma aureolatum (2.8%) and Amblyomma ovale (2.0%). There was a positive correlation between the presence of A. cajennense and H. canis infection.  相似文献   

The complete nucleotide sequences of L3 and S7 segments of Ibaraki virus encoding for the major inner capsid proteins, VP3 and VP7   总被引：2，自引：0，他引：2  

Iwata H  Manabe S  Yoshida A  Pereira EM  Inoue T 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2001,63(1):73-78

The complete nucleotide sequences of the genes encoding two of the major inner capsid proteins of Ibaraki virus (IBAV), belonging to epizootic hemorrhagic disease virus serotype 2 (EHDV-2) were determined. The L3 RNA segment is 2768 nucleotides in length which encodes VP3 polypeptides of 899 amino acid residues (M.W. 103 kDa). The S7 RNA segment, which encodes the VP7 core protein, is 1162 nucleotides in length and encodes 349 amino acids (M.W. 38 kDa). These RNA segments had the characteristic consensus motifs of Orbivirus RNA segments in termini, namely 5'-GUUAAA... and ...ACUUAC-3'. The comparison of the IBAV L3 and S7 sequences with those of other two EHDV-2 isolates revealed the higher homologies of 93% and 92% against EHDV-2 Australia isolate (EHDV-2AUS) and lower homologies of 80% and 81% against EHDV-2 North America isolate, respectively. The phylogenetic analysis based on L3 and S7 genes also indicated close relationships between IBAV and EHDV-2AUS. KEY WORDS: dsRNA gene, lbaraki virus, inner capsid, VP3, VP7.  相似文献