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31.
Nino Tavares Amazonas Luiz Antonio MartinelliMarisa de Cássia Piccolo Ricardo Ribeiro Rodrigues 《Forest Ecology and Management》2011,262(8):1551-1557
We considered whether ecological restoration using high diversity of native tree species serves to restore nitrogen dynamics in the Brazilian Atlantic Forest. We measured δ15N and N content in green foliage and soil; vegetation N:P ratio; and soil N mineralization in a preserved natural forest and restored forests of ages 21 and 52 years. Green foliage δ15N values, N content, N:P ratio, inorganic N and net mineralization and nitrification rates were all higher, the older the forest. Our findings indicate that the recuperation of N cycling has not been achieved yet in the restored forests even after 52 years, but show that they are following a trajectory of development that is characterized by their N cycling intensity becoming similar to a natural mature forest of the same original forest formation. This study demonstrated that some young restored forests are more limited by N compared to mature natural forests. We document that the recuperation of N cycling in tropical forests can be achieved through ecological restoration actions. 相似文献
32.
Andre Luiz Biscaia Ribeiro da Silva Daniel Tucker Price Abolfazl Hajihassani Juan Carlos Diaz-Perez Elizanilda Ramalho do Rego 《Communications in Soil Science and Plant Analysis》2020,51(13):1826-1833
ABSTRACT Root-knot nematodes (RKN; Meloidogyne spp.) cause enormous yield reductions in vegetable crops. While nematicides are the most effective method for controlling RKN in carrot (Dacatus carota), the efficacy of non-fumigant nematicides, compared to fumigants, is still not fully understood. The objective of this study was to evaluate the effect of 1,3-dichloropropene, a fumigant nematicide, and fluensulfone, a non-fumigant nematicide, on RKN control and yield of fresh market and processing carrot. Field experiments were conducted in a commercial farm in Lenox, GA. A randomized complete block design (r = 4) was used in a factorial arrangement of 3 nematicide treatments and 2 carrot cultivars. Nematicide treatments were the application of 1,3-dichloropropene, fluensulfone, and untreated control. Carrot cultivars were Baltimore (fresh marketing) and Belgrado (processing). In general, RKN population was low early season, averaging 0.8 RKN 100 cm?3 of soil. RKN populations increased with crop development and there were significant differences among nematicide treatments. At harvest, RKN populations were lower for fluensulfone (1.1 RKN 100 cm?3 of soil) and 1,3-dichloropropene (3.2 RKN 100 cm?3 of soil) compared to Control (26.4 RKN 100 cm?3 of soil); however, fluensulfone (91,278 kg ha?1) had higher yield than 1,3-dichloropropene (64,154 kg ha?1) and Control (61,908 kg ha?1). Carrot cultivars were similar for RKN population and yield. Overall, the non-fumigant nematicide was more beneficial for carrot production than the fumigant nematicide. 相似文献
33.
Jaciele Beserra de Lira Alberício Pereira de Andrade André Luiz Rodrigues Magalhães Fleming Sena Campos Gherman Garcia Leal de Araújo Diana Signor Deon 《Communications in Soil Science and Plant Analysis》2020,51(5):701-709
ABSTRACTThe objective is to determine the growth, yield and chemical characteristics of pearl millet irrigated with different levels of brackish water and organic matter in two cultivation cycles. The experimental design was randomized blocks in a 4 × 4 factorial arrangement, composed of 4 levels of brackish irrigation (25, 50, 75 and 100% evapotranspiration), 4 levels of organic matter (0, 15, 30 and 45 t ha?1) with 3 repetitions. Along two cultivation cycles, pearl millet crop was analyzed for: plant growth variables, fresh and dry mass production, water-use efficiency, and chemical composition. There was significant interaction between applied water levels and organic matter for lignin in the 2nd cut (P < .05). The number of leaves, number of dead leaves and fresh mass production were influenced by the isolated effect of brackish water levels in cut 1 (P < .05). In turn, fresh mass production, dry mass production, plant height, leaves length, panicle length, fresh mass production, crude protein and ether extract were influenced by the isolated effect of saline water levels in the 2nd cut (P < .05). Growth, biomass production and chemical composition variables in second cut are positively influenced by different brackish irrigation levels under low rainfall conditions. 相似文献
34.
Transformation of the nitrogen cycle: recent trends, questions, and potential solutions 总被引:12,自引:0,他引:12
Galloway JN Townsend AR Erisman JW Bekunda M Cai Z Freney JR Martinelli LA Seitzinger SP Sutton MA 《Science (New York, N.Y.)》2008,320(5878):889-892
Humans continue to transform the global nitrogen cycle at a record pace, reflecting an increased combustion of fossil fuels, growing demand for nitrogen in agriculture and industry, and pervasive inefficiencies in its use. Much anthropogenic nitrogen is lost to air, water, and land to cause a cascade of environmental and human health problems. Simultaneously, food production in some parts of the world is nitrogen-deficient, highlighting inequities in the distribution of nitrogen-containing fertilizers. Optimizing the need for a key human resource while minimizing its negative consequences requires an integrated interdisciplinary approach and the development of strategies to decrease nitrogen-containing waste. 相似文献
35.
36.
Souza LP Calegari F Zarbin AJ Marcolino-Junior LH Bergamini MF 《Journal of agricultural and food chemistry》2011,59(14):7620-7625
A direct determination of gallic acid was achieved at a carbon paste electrode modified with carbon nanotubes under differential pulse voltammetry conditions. The values obtained for gallic acid were used to estimate the antioxidant properties of the wine sample based on gallic acid oxidation. The proposed method is based on the gallic acid oxidation process at a modified carbon paste electrode (MCPE) containing 30% (m/m) of carbon nanotubes monitored at 0.35 V versus Ag/AgCl (KCl 3 mol L(-1)). Using the optimized experimental conditions, the calibration curve for gallic acid was linear in the concentration range from 5.0 × 10(-7) to 1.5 × 10(-5) mol L(-1) with a detection limit of 3.0 × 10(-7) mol L(-1). The MCPE was successfully applied for the determination of the antioxidant capacity for red and white wine samples without interference of glucose and ascorbic acid, and the obtained results were compared with the standard spectrophotometric method. 相似文献
37.
Marcello R. Roza Luiz Antonio F. Silva Mauricio Barriviera Alessandro L. Janu��rio Ana Cristina B. Bezerra Maria Clorinda S. Fioravanti 《Journal of veterinary science (Suw?n-si, Korea)》2011,12(4):387-392
The development of veterinary dentistry has substantially improved the ability to diagnose canine and feline dental abnormalities. Consequently, examinations previously performed only on humans are now available for small animals, thus improving the diagnostic quality. This has increased the need for technical qualification of veterinary professionals and increased technological investments. This study evaluated the use of cone beam computed tomography and intraoral radiography as complementary exams for diagnosing dental abnormalities in dogs and cats. Cone beam computed tomography was provided faster image acquisition with high image quality, was associated with low ionizing radiation levels, enabled image editing, and reduced the exam duration. Our results showed that radiography was an effective method for dental radiographic examination with low cost and fast execution times, and can be performed during surgical procedures. 相似文献
38.
39.
da Cruz CE de Oliveira LG Boabaid FM Zimermann FC Stein G Marks F Cerva C Lieberknecht C Canal CW Driemeier D 《Journal of zoo and wildlife medicine》2011,42(3):451-459
Pekin robins (Leiothrix lutea) were once the most widely kept softbills in captivity. As a result of the Convention on the International Trade of Endangered Species of Fauna and Flora (CITES-1997), the worldwide trade of wild-caught pekin robins has been prohibited due to the depletion of native populations of this species. In Brazil, as in other countries, pekin robins imported prior to the enactment of the CITES have disappeared from aviaries because the end of the birds' natural life span has passed, and only very few captive-bred pekin robins now exist. While captive propagation fails to address the primary causes of wild bird population decline, it might help the recovery of populations of this species. This article presents records made over a 10-yr period of a captive colony of pekin robins. Emphasis is placed on the management of the flock, the ailments affecting the birds, and the findings associated with bird losses. The main causes of bird losses included rearing management failures and age-related disorders. 相似文献
40.
Interactive responses of gala apple fruit volatile production to controlled atmosphere storage and chemical inhibition of ethylene action 总被引:2,自引:0,他引:2
Gala apples exposed to the ethylene action inhibitor 1-methylcyclopropene (1-MCP) for 12 h at 20 degrees C were stored at 1 degrees C in air or a controlled atmosphere (CA) maintained at 1 kPa O2 and 2 kPa CO2. Volatile compounds were measured after 4, 12, 20, and 28 weeks plus 1 or 7 days at 20 degrees C. Treatment with 1-MCP and then storage in air or CA or storage in CA without 1-MCP treatment reduced volatile production as compared to apples not treated with 1-MCP stored in air. The reduced production of esters, alcohols, aldehydes, acetic acid, and 1-methoxy-4-(2-propenyl)benzene was observed. Ester production by fruit stored in CA decreased throughout the storage period regardless of previous 1-MCP treatment. The production of esters, alcohols, aldehydes, acetic acid, and 1-methoxy-4-(2-propenyl)benzene by 1-MCP-treated fruit stored in air plus 7 days at 20 degrees C increased after 20 or 28 weeks of storage. Continuous exposure to 417 micromol m(-3) ethylene for 7 days at 20 degrees C after 12 or 28 weeks of storage stimulated production of many volatile compounds, primarily esters and alcohols, by fruit stored in CA or 1-MCP-treated apples stored in air. However, exposure to ethylene had no effect on the production of aldehydes or acetic acid. 相似文献