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1.
David R Bayne David Dunseth Cecilio García Ramirios 《Aquaculture (Amsterdam, Netherlands)》1976,7(2):133-146
A supplementary feed containing 30% coffee pulp was evaluated for use in the culture of Tilapia aurea in El Salvador, Central America. A comparison of the coffee pulp feed with a feed containing all of the same ingredients except coffee pulp was made with T. aurea raised in 1.0-m3 cages suspended in a fertilized earthen pond. Survival was high in all treatments and there was no significant difference in average weight gain between groups of fish receiving the two experimental feeds. Production trials were conducted in 100-m2 fish pens and in 0.05-ha earthen ponds. Pen-raised fish receiving coffee pulp feed grew faster throughout the experiment, and total production was approximately twice that in control treatments. Highest production in pens was 1.25 kg/m2 per year. Results of production pond trials using T. aurea at 9 000/ha and stocked with the piscivorous Cichlasoma managuense yielded an estimated 3 392 kg/ha per year in fed treatments and 2 049 kg/ha per year in controls. Low feed conversion (1.92) and low feed cost resulted in an increase in net annual earnings of $251.00/ha. 相似文献
2.
R. Delgado J. M. Martín- García C. Oyonarte & G. Delgado 《European Journal of Soil Science》2003,54(1):1-16
Some aspects of the genesis of terrae rossae are still subject to controversy while others related to the genesis of the mineral fraction have been studied very little. We have studied four terrae rossae over limestone (two Chromic‐Leptic Luvisols, a Rhodi‐Leptic Luvisol and a Chromi‐Leptic Cambisol) in Sierra Gádor (Almería, southern Spain), in particular the various formation processes by (i) examination of their morphological, analytical and mineralogical characteristics (including crystallochemical parameters of the mica), (ii) examination of the insoluble residue of the gravel and rock, (iii) scanning electron microscopy (SEM) of sand and silt grains, and (iv) examination of the geochemistry of the soil solution. We have investigated the autochthonous or allochthonous nature of the soil material (fine earth and gravel) in relation to the rocky substrate, concluding that both origins are possible. Our SEM study of the morphology of the quartz grains shows that some are insoluble residue and some are probably wind blown from desert and coastal sources. The micas in the fine earth fractions are inherited from the insoluble residue. Comparison of the crystallochemical parameters of micas in the insoluble residue and the soil clay shows that the clay has more SiIV and (Fe, Mg)VI, and less AlIV, AlVI and x (layer charge) than the insoluble residue. It also has fewer polytypes 2M1 and more 1M and has a smaller crystal size, especially in B horizons. The kaolinite is of varied origins including neoformation and inheritance from underlying rock. Some of the kaolinite and some mica has been blown in from elsewhere, probably from desert and coastal sources. The soils have undergone other typical processes of terrae rossae including dissolution of carbonate, illuviation of clay and iron oxides, and rubifaction. 相似文献
3.
Ruíz-Henestrosa VP Carrera Sánchez C Yust Mdel M Pedroche J Millan F Rodríguez Patino JM 《Journal of agricultural and food chemistry》2007,55(4):1536-1545
In this contribution, we have determined the effect of limited enzymatic hydrolysis on the interfacial (dynamics of adsorption and surface dilatational properties) and foaming (foam formation and stabilization) characteristics of a soy globulin (beta-conglycinin, fraction 7S). The degree of hydrolysis (DH = 0, 2, and 5%), the pH of the aqueous solution (pH = 5 and 7), and the protein concentration in solution (at 0.1, 0.5, and 1 wt %) were the variables studied. The temperature and the ionic strength were maintained constant at 20 degrees C and 0.05 M, respectively. The rate of adsorption and surface dilatational properties (surface dilatational modulus, E, and loss angle) of beta-conglycinin at the air-water interface depend on the pH and DH. The adsorption decreased drastically at pH 5.0, close to the isoelectric point of beta-conglycinin, because of the existence of a lag period and a low rate of diffusion. The interfacial characteristics of beta-conglycinin are much improved by enzymatic treatment, especially in the case of acidic aqueous solutions. Hydrolysates with a low DH have improved functional properties (mainly foaming capacity and foam stability), especially at pH values close to the isoelectric point (pI), because the protein is more difficult to convert into a film at fluid interfaces at pH approximately equal to pI. 相似文献
4.
Thomas Abeli Cecilio F. Caldeira Elena Barni Consolata Siniscalco Valentina Parco Graziano Rossi 《水产资源保护:海洋与淡水生态系统》2020,30(9):1719-1722
- Scientific publications on the conservation of threatened species can drive practical conservation solutions for endangered species. Yet, a posteriori assessment of the impact of such publications is rarely seen in the scientific literature.
- The impact of two articles published in Aquatic Conservation: Marine and Freshwater Ecosystems (AQC) on the conservation of the endangered quillwort Isoëtes malinverniana is assessed. The articles were the result of a 10‐year study on the focal species that eventually led to the first reintroduction of I. malinverniana. The first article described the development of a cost‐effective model for the selection of suitable reintroduction sites for the species. The second article provided a summary of the techniques used to reintroduce the species and included techniques of ex situ propagation, recipient site preparation, planting methods, and monitoring.
- This article reviews the practical conservation actions for I. malinverniana that followed the publication of two AQC papers and how they may affect research and conservation for other quillworts and aquatic macrophytes.
- The results were surprising and went well beyond the initial expectations of the authors. Both AQC publications stimulated the conservation of I. malinverniana from different points of view. They contributed by informing scientists and policymakers of the risk of extinction of this species, leading to the establishment of a new protected area in Piedmont (northern Italy).
- Our published data represent a sound starting point for funding opportunities in the context of the European Union LIFE programme. Further impacts include an expansion of knowledge on oligotrophic habitat management, the assessment of conservation status, and the education of the general public, with the last of these greatly enhanced by the two ex situ collections created in the botanic gardens of Tourin and Pavia. Interestingly, other authors are now using our approach in research and conservation on other endemic and endangered quillworts worldwide.
5.
Ruíz-Henestrosa VP Sánchez CC Rodríguez Patino JM 《Journal of agricultural and food chemistry》2008,56(7):2512-2521
In this contribution, we have analyzed the effect of sucrose on dynamic interfacial (dynamic surface pressure and surface dilatational properties) and foaming (foam capacity and foam stability) characteristics of soy globulins (7S and 11S). The protein (at 1 x 10(-3), 1 x 10(-2), 0.1, and 1 wt %) and sucrose (at 0, 0.25, 0.5, and 1.0 M) concentrations in aqueous solution and the pH (at 5 and 7), and ionic strength (at 0.05 and 0.5 M) were analyzed as variables. The temperature was maintained constant at 20 degrees C. We have observed the following. (i) The dynamics of adsorption (presence of a lag period, diffusion, and penetration at the air-water interface) of soy globulins depend on the peculiar molecular features of proteins (7S or 11S soy globulin) and the level of association/dissociation of these proteins by varying the pH and ionic strength, as well as the effect of sucrose in the aqueous phase on the unfolding of the protein. The rate of adsorption increases with the protein concentration in solution, at pH 7 compared to pH 5, at high ionic strength, and in the absence of sucrose. (ii) The surface dilatational properties reflect the fact that soy globulin adsorbed films exhibit viscoelastic behavior. The surface dilatational modulus increases at pH 7 compared to pH 5, but decreases with the addition of sucrose into the aqueous phase. (iii) The rate of adsorption and surface dilatational properties (surface dilatational modulus and phase angle) during adsorption at the air-water interface play an important role in the formation of foams generated from aqueous solutions of soy globulins. (iv) The increased interfacial adsorption (at high surface pressures) and the combined effects of interfacial adsorption and interfacial interactions between adsorbed soy globulin molecules (at high surface dilatational modulus) can explain the higher stability of the foam, with few exceptions. 相似文献
6.
Natália Martins Teixeira Reges Heinrichs Carolina Santos B. Bonini Joshua Afzal Guilherme Constantino Meirelles Cecilio Viega Soares Filho 《Journal of plant nutrition》2019,42(1):89-98
The intensification of livestock yield requires advances in the management and fertilization of forage crops. This study was conducted to determine the dry weight yield (DWY) along with the concentration and amount of nutrients of Megathyrsus maximum cv. Mombasa. The treatments were arranged in a factorial scheme 6?×?2, six leaf rates of Zn chelate and two soil types (Entisols and Ultisol) with low and medium Zn content and four replicates. Entisols with low Zn content and Ultisol with average Zn content were used plus a control treatment with Zn sulfate. The Zn chelate and Zn sulfate foliar application did not affect the DWY. The tillering and DWY were higher in Ultisol than in Entisol. The Zn content in DWY was directly proportional to rate chelated Zn. The root dry weight yield of Mombasa grass reduced with the chelated Zn foliar application in Entisol and had no effect on Ultisol. 相似文献
7.
Brbara A. Willaarts Cecilio Oyonarte Miriam Muoz‐Rojas Juan Jos Ibez Pedro A. Aguilera 《Land Degradation \u0026amp; Development》2016,27(3):603-611
Managing soil carbon requires accurate estimates of soil organic carbon (SOC) stocks and its dynamics, at scales able to capture the influence of local factors on the carbon pool. This paper develops a spatially explicit methodology to quantify SOC stocks in two contrasting regions of Southern Spain: Sierra Norte de Sevilla (SN) and Cabo de Gata (CG). Also, it examines the relationship between SOC stocks and local environmental factors. Results showed that mean SOC stocks were 4·3 kg m−2 in SN and 3·0 kg m−2 in CG. Differences in SOC in both sites were not significant, suggesting that factors other than climate have a greater influence on SOC stocks. A correlation matrix revealed that SOC has the highest positive correlation with clay content and soil depth. Based on the land use, the largest SOC stocks were found in grassland soils (4·4 kg m−2 in CG and 5·0 kg m−2 in SN) and extensive crops (3·0 kg m−2 in CG and 5·0 kg m−2 in SN), and the smallest under shrubs (2·8 kg m−2 in CG and 3·2 kg m−2 in SN) and forests soils (4·2 kg m−2 in SN). This SOC distribution is explained by the greatest soil depth under agricultural land uses, a common situation across the Mediterranean, where the deepest soils have been cultivated and natural vegetation mostly remains along the marginal sites. Accordingly, strategies to manage SOC stocks in southern Spain will have to acknowledge its high pedodiversity and long history of land use, refusing the adoption of standard global strategies. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
8.
A study was carried out on some basic characteristics of the organic matter in the surface horizons of soils from the two different geological (calcareous and acid metamorphic rocks) and ecological systems under a Mediterranean climate in Southeast Spain. The results show some noticeable differences in soil organic matter composition. This is likely due to typical Mediterranean climate and well adapted vegetation. There is a tendency towards a greater stability for the soil humus formed under slightly alkaline soil in comparison to the slightly acidic environment. The samples taken from the latter environment have a higher content in free organic matter, a lower content in total extractable humin and a greater relative proportion of aliphatic chains and lignin in the humic acids. The results also suggest some differences caused by the type of vegetation (forest and scrubland ecosystems) in the soil humus chemistry, with a more obvious negative effect under reforestations with species of Pinus in an acidic soil environment (a higher content in free organic matter, lesser presence of fungal-derived perylenequinonic pigments in the humic acids, and a higher content in little evolved forms of nitrogen and lignin in the humic acids). In general the organic matter under scrubland and Quercus vegetation is more decomposed and the humus is more evolved than under Pinus vegetation. 相似文献
9.
Rodríguez Patino JM Rodríguez Niño MR Carrera Sánchez C 《Journal of agricultural and food chemistry》2003,51(1):112-119
In this work we have used different and complementary interfacial techniques (surface film balance, Brewster angle microscopy, and interfacial dilatational rheology) to analyze the static (structure, morphology, reflectivity, miscibility, and interactions) and dynamic characteristics (surface dilatational properties) of beta-casein and monoglyceride (monopalmitin and monoolein) mixed films spread on the air-water interface. The static and dynamic characteristics of the mixed films depend on the interfacial composition and the surface pressure. At higher surface pressures, collapsed beta-casein residues may be displaced from the interface by monoglyceride molecules with important repercussions on the interfacial characteristics of the mixed films. From the frequency dependence of the surface dilatational properties, we have elucidated the relationships between interfacial dilatational rheology and changes in molecular structure, interactions, miscibility, and relaxation phenomena in protein-monoglyceride mixed films. 相似文献
10.
Barrera CR 《Science (New York, N.Y.)》2006,313(5787):614