Hg, Cu, Pb, Cd, and Zn Accumulation in Macrophytes Growing in Tropical Wetlands

The concentrations of Hg, Cu, Pb, Cd, and Zn accumulated by regional macrophytes were investigated in three tropical wetlands in Colombia. The studied wetlands presented different degrees of metal contamination. Cu and Zn presented the highest concentrations in sediment. Metal accumulation by plants differed among species, sites, and tissues. Metals accumulated in macrophytes were mostly accumulated in root tissues, suggesting an exclusion strategy for metal tolerance. An exception was Hg, which was accumulated mainly in leaves. The ranges of mean metal concentrations were 0.035?C0.953 mg g^?1 Hg, 6.5?C250.3 mg g^?1 Cu, 0.059?C0.245 mg g^?1 Pb, 0.004?C0.066 mg g^?1 Cd, and 31.8?363.1 mg g^?1 Zn in roots and 0.033?C0.888 mg g^?1 Hg, 2.2?C70.7 mg g^?1 Cu, 0.005?C0.086 mg g^?1 Pb, 0.001?C0.03 mg g^?1 Cd, and 12.6?C140.4 mg g^?1 Zn in leaves. The scarce correlations registered between metal concentration in sediment and plant tissues indicate that metal concentrations in plants depend on several factors rather than on sediment concentration only. However, when Cu and Zn sediment concentrations increased, these metal concentrations in tissues also increased in Eichhornia crassipes, Ludwigia helminthorriza, and Polygonum punctatum. These species could be proposed as Cu and Zn phytoremediators. Even though macrophytes are important metal accumulators in wetlands, sediment is the main metal compartment due to the fact that its total mass is greater than the corresponding plant biomass in a given area.     

Performance,endocrine, metabolic,and reproductive responses of Nellore heifers submitted to different supplementation levels pre- and post-weaning

The present study was conducted to evaluate the effects of high and low supplementation levels pre- and post-weaning on performance, endocrine, metabolic, and reproductive responses of Nellore heifers. Fifty Nellore heifers with 132?±?9.9 kg average body weight (BW) and 138?±?19 days of age were supplemented from 4 to 14 months. The heifers were distributed into five supplementation plans: HH—6 g/kg of BW of supplement pre- and post-weaning, HL—6 g/kg of BW of supplement pre-weaning and 3 g/kg post-weaning, LH—3 g/kg of BW pre-weaning and 6 g/kg of BW post-weaning, LL—3 g/kg of BW pre- and post-weaning, and CC—control, no supplementation. Interactions were not significant (P?>?0.10). The level of supplement fed pre-weaning did not affect any of the performance variables evaluated at the end of the experiment (P?>?0.10). There was a significant effect of supplementation and level of supplementation fed post-weaning on average daily gain (ADG) and final BW (P?<?0.05). Overall ADG was also affected only by supplementation and level of supplement fed post-weaning (P?<?0.05) with animals receiving 6 g/kg of BW post-weaning gaining more weight. Follicular diameter was greater in animals that received 6 g/kg of BW post-weaning (P?<?0.05). In summary, performance, endocrine, metabolic, and reproductive variables evaluated in the current study were improved by the level of supplement fed post-weaning. Heifers receiving supplementation of 6 g/kg of BW post-weaning had greater responses, independent of the level received during the pre-weaning phase.     

Effect of marine by‐product meals on hen egg production parameters,yolk lipid composition and sensory quality

The effect of including 5% marine by‐product meals in feeds of laying hens on egg production, composition and sensory characteristics was tested. Marine by‐product meals were prepared using two methods: (i) cooking (100°C/10 min) followed by drying (60°C/24 hr) or (ii) grinding followed by drying. The raw materials used for meal production were scallop or squid viscera, shrimp heads or whole mackerel. A total of 108 laying hens were allocated to nine diet treatments; one control diet (corn and soya bean based) and eight experimental diets, containing 95% of the control feed and 5% of the experimental meal for three weeks. Daily intake was higher in hens fed the dried mackerel and cooked shrimp meals. All the experimental treatments showed significantly higher concentration of n‐3 HUFA in yolk reserves and phospholipids compared to the control (0.12–0.13 g per 100 g), especially those with scallop or squid prepared by both methods (0.53–0.95 g per 100 g). Scallop, squid and shrimp meal inclusion in the feed produced eggs with more astaxanthin (0.22 mg per 100 g) while this carotenoid was absent in the control and mackerel treatments. Visual evaluation of raw yolk colour increased with the inclusion of marine by‐product meals with higher values in hens fed shrimp heads (13), followed by scallop viscera (11), squid viscera (9), and with similar values for mackerel and control (4). The taste, aroma, texture and colour of cooked eggs from different treatments were not statically different when evaluated by a panel of 60 untrained people. These results suggest that meals from marine by‐products are a better alternative for improving egg yolk composition by increasing n‐3 HUFA when compared to fishmeal as they also increase astaxanthin and yolk pigmentation without affecting egg sensory characteristics.     

Field Performance of Pinus radiata D. Don Produced in Nursery with Different Types of Containers

We have studied the development in nurseries of containerized Pinus radiata produced with different container systems in order to choose the most suitable system for producing well-balanced plants with an optimal root system. At the end of the production period, significant differences were found in morphological responses among the seedlings to the various container characteristics. Seedlings grown in containers that permitted lateral air puning presented less growth and lower biomass production. However, root deformations were more frequent and severe in plants produced in closed-wall containers. Field performance was likewise mainly affected by container type and plant growth rate, as faster grown plants showed more problems of stability than plants with a balanced root and stem development.     

Recent changes in landscape structure and function in a mediterranean region of SW Spain (1950–1984)

Recent economic development has altered landscape structure and function of a mediterranean region in Southwestern Spain. Intensive agricultural systems have concentrated in the more fertile areas, while marginal ones have been abandoned. As a result, landscape structure has changed. Consequences of this structural change on landscape processes are discussed.     

Intraovarian localization of growth factors in induced cystic ovaries in rats

We hypothesized that the special hormonal environment present in animals with cystic ovarian disease (COD) interferes with cellular production of growth factors (GFs). The objective of the present study was to characterize the expression of insulin-like growth factor (IGF)-I, fibroblast growth factor (FGF)-2 and vascular endothelial growth factor (VEGF) in induced COD using immunohistochemistry. We used an experimental model based on the exposure to constant light of adult rats during 15 weeks. We quantified the expression of GFs in cystic and normal ovaries by the Immunohistochemical Stained Area (IHCSA). In animals with COD, a significant reduction in the IHCSA of IGF-I in the follicular fluid, theca and granulosa layers of cysts occurred; and an increase in the interstitial tissue with regard to the control group. We found moderate immunoreactivity of FGF-2 in granulosa and theca layers of secondary and tertiary follicles and lower expression in the granulosa and theca interna layers of cystic follicles. Immunoexpression of VEGF was found in granulosa and theca cells of secondary and tertiary follicles. This study shows changes in the ovarian expression of IGF-I, FGF-2 and VEGF in induced COD. We can propose that an alteration in the control of the follicular dynamic, through the GFs, added to other features, could be involved in the ovarian cyst pathogenesis.     

Characterization of the Wx gene in diploid Aegilops species and its potential use in wheat breeding

Wx gene encodes for the granule-bound starch synthase I or waxy protein, which is the sole enzyme responsible for amylose synthesis in wheat seeds. The Aegilops species, which are related to wheat, could be important sources of variation in this gene. In addition to its role in starch quality, this gene has been used in phylogenetic studies of wheat. The current study evaluated the variability of Wx gene in seven diploid species of Aegilops genus and compared their nucleotide sequences with the wheat homeologous genes. Nineteen new Wx alleles were found in the seven species evaluated. The alleles detected in two species of the Sitopsis section, Ae. searsii and Ae. speltoides, were related to the Wx-B1 gene of wheat. Two more of the Sitopsis species did not appear to be associated with this genome, whereas the remaining species were related to the Wx-D1 gene of wheat. The results showed an important variation of the Wx gene present in the Aegilops genus, and the 19 new Wx alleles detected could enlarge the genetic pool of wheat.     

The 2010 Mw 8.8 Maule megathrust earthquake of Central Chile, monitored by GPS

Large earthquakes produce crustal deformation that can be quantified by geodetic measurements, allowing for the determination of the slip distribution on the fault. We used data from Global Positioning System (GPS) networks in Central Chile to infer the static deformation and the kinematics of the 2010 moment magnitude (M(w)) 8.8 Maule megathrust earthquake. From elastic modeling, we found a total rupture length of ~500 kilometers where slip (up to 15 meters) concentrated on two main asperities situated on both sides of the epicenter. We found that rupture reached shallow depths, probably extending up to the trench. Resolvable afterslip occurred in regions of low coseismic slip. The low-frequency hypocenter is relocated 40 kilometers southwest of initial estimates. Rupture propagated bilaterally at about 3.1 kilometers per second, with possible but not fully resolved velocity variations.     

Influence of blending on the content of different compounds in the biological aging of sherry dry wines

Principal components analysis to examine the effect of blending (viz. the mixing and transfer of wine between cask rows in a "criaderas and solera" system) on metabolic activity in flor yeasts during biological aging of sherry dry wines was carried out. The variables used in the analysis were the wine compounds most deeply involved in the flor yeast metabolism, namely ethanol, acetaldehyde, glycerol, acetic acid, and l-proline. The greatest blending effect was found to be on the third and second "criadera", which are the stages where the yeasts show a high metabolic activity. The stages holding the oldest wine (viz. the first criadera and the solera) exhibited no differences before and after blending; therefore, the yeasts have a decreased biological activity in them and physical-chemical aging processes seemingly prevail over it.     

Modifications of organic matter and enzymatic activities in response to change in soil use in semi‐arid mountain ecosystems (southern Spain)

Soil organic matter composition and biochemical properties were determined in mountain calcimorphic Mediterranean soils under different vegetation (cultivated soils, secondary bush, high mountain bush, juniper, evergreen oak and pine) to assess the impact of soil use on the size and activity of microbial communities. Our results indicated that clearing forest leads to a general decline in the performance of soil organic carbon sequestration and associated enzymatic activities. However, when soil enzymatic activities (dehydrogenase, catalase, phosphodiesterase, β‐glucosidase, urease and casein‐protease) were expressed as ratios to total organic carbon (specific activities), a conspicuous increase in their activities was observed in cleared soils as compared with forest soils, suggesting enhanced hydrolytic potential in the former. In addition, the negative correlation observed between qCO₂ (metabolic quotient) and water retention at ?1500 kPa, could be interpreted as an adaptive strategy against low soil moisture by microbial communities in cleared soils. This indicates the importance of describing soil quality in terms of long‐term soil organic C sequestration and/or resistance of the organic matter to microbial transformation. These features were reflected in the visible and infrared spectra of humic acids, which suggested humification mechanisms involving mainly an alteration of plant macromolecules with poor incorporation of characteristic microbial metabolites in the forest soils whereas the opposite effect was observed in cleared soils.