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131.
Modeling the Exchanges of Energy, Water, and Carbon Between Continents and the Atmosphere 总被引:19,自引:0,他引:19
PJ Sellers RE Dickinson DA Randall AK Betts FG Hall JA Berry GJ Collatz AS Denning HA Mooney CA Nobre N Sato CB Field A Henderson-Sellers 《Science (New York, N.Y.)》1997,275(5299):502-509
Atmospheric general circulation models used for climate simulation and weather forecasting require the fluxes of radiation, heat, water vapor, and momentum across the land-atmosphere interface to be specified. These fluxes are calculated by submodels called land surface parameterizations. Over the last 20 years, these parameterizations have evolved from simple, unrealistic schemes into credible representations of the global soil-vegetation-atmosphere transfer system as advances in plant physiological and hydrological research, advances in satellite data interpretation, and the results of large-scale field experiments have been exploited. Some modern schemes incorporate biogeochemical and ecological knowledge and, when coupled with advanced climate and ocean models, will be capable of modeling the biological and physical responses of the Earth system to global change, for example, increasing atmospheric carbon dioxide. 相似文献
132.
Maribela Pestana Pedro José Correia Teresa Saavedra Florinda Gama Susana Dandlen Gustavo Nolasco 《Journal of plant nutrition》2013,36(13):2035-2047
In the present experiment, we studied the interaction between copper (Cu) and iron (Fe) in strawberry plants grown in nutrient solutions containing different concentrations of Fe. Plants grown in the absence of iron (Fe0) had the characteristic symptoms of Fe deficiency, with smaller chlorotic leaves, less biomass, acidification of the nutrient solution, and roots that were smaller and less ramified, while no symptoms of Fe deficiency were observed in plants grown with Fe. A greater amount of Cu was found in roots of chlorotic plants than in those grown with Fe, while plants grown with 20 μM of Fe (Fe20) in the nutrient solution had a greater amount of Fe compared with plants from the other treatments. Chlorotic plants (Fe0) and plants grown with the greatest level of Fe (Fe20) had a greater root ferric chelate reductase (FC-R; EC 1.16.1.17) activity compared with the other treatments with 5 or 10 μM Fe in the nutrient solution. The same pattern was obtained for relative FC-R mRNA concentration and for the sum of Fe and Cu contents in shoots (leaves plus crowns). The DNA obtained from amplification of the FC-R mRNA was cloned and several of the inserts analysed by single strand confirmation polymorphism (SSCP). Although there were different SSCP patterns in the Fe20 treatment, all the inserts that were sequenced were very similar, excluding the hypothesis of more than one FC-R mRNA species being present. The results suggest that Cu as well as Fe is involved in FC-R expression and activity, although the mechanism involved in this regulation is unknown so far. Both small contents of Fe and Cu in plants led to an over-expression of the FC-R gene and enhanced FC-R activity in strawberry roots. 相似文献
133.
Pedro José Correia Amarilis de Varennes Florinda Gama Teresa Saavedra Maribela Pestana 《Journal of plant nutrition》2013,36(16):2103-2115
AbstractIron (Fe) deficiency is a nutritional disorder in plants. Poncirus trifoliata is susceptible to Fe deficiency, but symptoms of Fe deficiency are rare in Ceratonia siliqua, a slow-growing species. Specimens of the two species were grown in nutrient solutions containing three Fe concentrations: without Fe (0?µM), 1?µM Fe, and either 10?µM Fe (for Ceratonia) or 40?µM Fe (for P. trifoliata). Growth, the degree of chlorosis, the plant mineral composition, and the activity of the root ferric chelate-reductase (FCR) were assessed. Ceratonia plants exposed to 1?µM Fe were efficient at using Fe in the synthesis of chlorophyll. The activity of FCR was enhanced in the total absence of Fe. In Poncirus a low activity of the FCR was observed in plants with no Fe. The balance between micronutrients in the Ceratonia roots was not affected with 1?µM Fe compared with the higher Fe concentration treatments. 相似文献
134.
Jamile da Costa Araújo Priscila Vieira e Rosa Maria das Dores Correia Palha Paulo Borges Rodrigues Rilke Tadeu Fonseca de Freitas Alanna do Socorro Lima da Silva 《Tropical animal health and production》2013,45(3):729-735
Chelonians have been exploited since ancient times for their meat, eggs, fat, and offal, among other things. Among these animals, there is Scorpion mud turtle (Kinosternon scorpioides) which is an omnivorous turtle with semiaquatic habits and is widely consumed in Brazil. The aim of this study was to evaluate the influence of different feeding management systems on the reproductive performance of captive-bred Scorpion mud turtles, including egg quality and chemical composition. Study animals included 15 males and 48 females, divided into three groups. Animals were fed with either a commercial diet or a commercial diet supplemented with one of two different mixes (wet diet). All animals were fed at 1 % BW/day divided on Mondays, Wednesdays, and Fridays. Treatments were as follows: TR?=?100 % fish food (22 % CP); TRM1?=?70 % fish food?+?30 % mix 1 (bovine offal and fish); TRM2?=?70 % fish food?+?30 % mix 2 (bovine offal, fish, and shrimp). Samples were collected during 7 months, and eggs were identified, weighed, measured, and frozen for later analysis. Statistical analyses, including ANOVA, were performed using the program SAEG 9.0. Measurements taken from the nests were compared using the Tukey’s test (P?<?0.05). The different diets were associated with differential egg-laying performance and eggshell thickness. Animals fed with wet diets containing protein of animal origin displayed the best performance. Furthermore, nests with fewer eggs contained eggs of better external quality (e.g., greater length, width, and eggshell thickness). Finally, animals fed with only commercial feed produced eggs with lower saturated fatty acid content. 相似文献
135.
CASE HISTORY: An adult male Birman cat was evaluated for recurrent, intermittent vomiting or regurgitation, occasionally associated with abdominal discomfort. CLINICAL FINDINGS AND DIAGNOSIS: Radiographs, including an oesophogram, indicated an oesophageal obstruction. Prior to treatment, the cat's condition deteriorated and it was euthanised at the owner's request. Post-mortem examination revealed a gastro-oesophageal intussusception, a trichobezoar impacted into the intussusceptum, and a dilated oesophageal hiatus consistent with a chronic hiatal hernia. CLINICAL RELEVANCE: Gastro-oesophageal intussusception is a rare condition in cats. Its aetiology in relation to a pre-existing hiatal hernia and a trichobezoar is discussed. 相似文献
136.
137.
Carla Barradas Alan J. L. Phillips António Correia Eugénio Diogo Helena Bragança Artur Alves 《European journal of plant pathology / European Foundation for Plant Pathology》2016,144(2):245-256
Eucalyptus globulus, a non-native species, is currently the most abundant forest species in Portugal. This economically important forest tree is exploited mainly for the production of pulp for the paper industry. The community of Botryosphaeriaceae species occurring on diseased and healthy E. globulus trees was studied on plantations throughout the country. Nine species from three different genera were identified, namely Botryosphaeria (B. dothidea), Diplodia (D. corticola and D. seriata) and Neofusicoccum (N. australe, N. algeriense, N. eucalyptorum, N. kwambonambiense, N. parvum and Neofusicoccum sp.). Of these, N. algeriense, D. corticola and D. seriata are reported for the first time on E. globulus, while N. algeriense, N. eucalyptorum and N. kwambonambiense correspond to first reports in Portugal. The genus Neofusicoccum was clearly dominant with N. australe and N. eucalyptorum being the most abundant species on both diseased and healthy trees. In artificial inoculation trials representative isolates from all nine species were shown to be pathogenic to E. globulus but there were marked differences in aggressiveness between them. Thus, D. corticola and N. kwambonambiense were the most aggressive while B. dothidea and D. seriata were the least aggressive of the species studied. 相似文献
138.
Growth performance of the early life stages of broad‐nosed pipefish,Syngnathus typhle (L.) fed different live or frozen diets 下载免费PDF全文
This work tested the effect of using different live and frozen feed on the growth performance of Syngnathus typhle. It was divided into two experiments. In Experiment I Artemia and Atlantic ditch shrimp (Palaemonetes varians) larvae were used as live diets, whilst in Experiment II frozen mysids Mesopodopsis slabberi and frozen P. varians were used. At the end of the first experiment juvenile pipefish grew significantly more when fed P. varians (P < 0.05) with an overall Weight Gain (WG) of 914.8 ± 79.3% bw day?1, compared to Artemia fed fish (WG = 683.2 ± 14.7%). Both mean Specific Growth Rate (SGR) and survival were similar between dietary treatments and did not vary significantly (P > 0.05). In Experiment II juveniles were weaned with frozen diets but no significant differences were found between the two tested diets in all parameters tested. Final WG was 516.5 ± 63.3% and 566 ± 17.6%, and Feed Conversion Ratio (FCR) was 30 ± 1.5% and 28.2 ± 1.2% for animals fed P. varians and M. slabberi respectively. Results indicate that P. varians is an adequate diet to use during initial stages of the S. typhle life cycle and should be considered as a frozen diet for subsequent life stages of this species as an alternative to currently known natural diets. 相似文献
139.
Phylogeny,distribution and pathogenicity of Lasiodiplodia species associated with dieback of table grape in the main Brazilian exporting region 下载免费PDF全文
K. C. Correia M. A. Silva M. A. de Morais Jr J. Armengol A. J. L. Phillips M. P. S. Câmara S. J. Michereff 《Plant pathology》2016,65(1):92-103
Botryosphaeria dieback is an important disease of table grape in the São Francisco Valley, the main Brazilian exporting region. The objectives of this study were to identify species of Lasiodiplodia associated with botryosphaeria dieback of table grapes in the São Francisco Valley, investigate the prevalence and distribution of the species in the region, and evaluate their pathogenicity and virulence in green shoots of table grape. A total of 112 Lasiodiplodia isolates were obtained from 14 vineyards, located in Casa Nova, Juazeiro and Petrolina. Fungal identifications were made using phylogenetic analysis based on partial sequences of translation elongation factor 1‐α (EF1‐α) and internal transcribed spacer (ITS) sequences, in combination with morphometric characteristics of conidia. Eight species of Lasiodiplodia were identified: L. brasiliense, L. crassispora, L. egyptiacae, L. euphorbicola, L. hormozganensis, L. jatrophicola, L. pseudotheobromae and L. theobromae. Except for L. crassispora, L. pseudotheobromae and L. theobromae, all the other species are reported for the first time on grapevine worldwide. The distribution of Lasiodiplodia species differed between the three table grape populations of São Francisco Valley. All Lasiodiplodia species isolated in this study were present in the population of Casa Nova and Lasiodiplodia theobromae was the most prevalent. All species of Lasiodiplodia were pathogenic on detached green shoots of grapevine, with L. brasiliense being the most virulent. 相似文献
140.