Acaciapollenites acaciae sp. nov., una nueva políade de mimosoidea del neógeno, en la Cuenca del Colorado, Argentina

Fossil mimosoid polyads have been recently recovered from Neogene deposits in the Colorado Basin, Argentina, and the new species Acaciapollenites acaciae sp. nov. is described, which is closely similar to polyads of species included in Acacia Miller subgenus Acacia Vassal. It is characterized by colporate apertures on the distal face of the pollen grains, a typical polyad of the subgenus Acacia species. The new polyad species is very similar to those of the extant Acacia curvifructa Burkart. Comparing the habitat of subgenus Acacia extant species, the Acaciapollenites acaciae occurrence suggests drier and warmer paleoclimatic conditions than today for the Late Miocene-Early Pliocene in the Colorado Basin. Paleogeographic data of Acacia pollen diversity are discussed. A similar early diversification and distribution of Acacia genus is recognized for the new and old worldPolíades afines a Mimoisoideas fueron recuperadas de depósitos del Neógeno de la cuenca del Colorado, Argentina. Por sus detalles morfológicos es reconocida una nueva especie con afinidad botánica a las especies actuales del género Acacia, subgénero Acacia. Acaciapollenites acaciae sp. nov. se distingue por presentar aperturas colporadas sobre la superficie distal de sus granos de polen, políade típica de las especies del subgénero Acacia. La nueva especie de políade se compara con las de la especie actual Acacia curvifructa. Comparando el hábitat de las actuales especies del subgénero Acacia, la presencia de Acaciapollenites acaciae en el Neógeno de la cuenca del Colorado, sugiere condiciones paleoclimáticas mas áridas y cálidas que las de hoy día. Se discuten los datos paleogeográficos de la diversidad de Acacia. Es reconocida tanto para el nuevo como para el viejo mundo, una temprana diversificación y dispersión del género.Fil: Caccavari, Marta Alicia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales “Bernardino Rivadavia”; Argentina. Universidad Nacional del Sur. Departamento de Geología; ArgentinaFil: Guler, Maria Veronica. Universidad Nacional del Sur. Departamento de Geología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Cross-amplification and characterization of polymorphic microsatellite markers from Acacia (Senegalia) mellifera and Acacia brevispica to Acacia senegal (L.) Willd.

Seven polymorphic microsatellite markers isolated from Acacia brevispica and Acacia mellifera were successfully cross-amplified in Acacia senegal. The loci were surveyed for polymorphism using 30 samples. Allelic diversity ranged from 4 (Ame02, Ab06 and Ab18) to 13 (Ab26) per locus. The expected heterozygosity (HE) ranged from 0.543 (Ame02) to 0.868 (Ab26) while observed heterozygosity (HO) ranged from 0.516 (Ame05) to 0.800 (Ame03). Cross amplification of these loci represents a potential source of co-dominant marker and will be useful in the study of genetic diversity, structure, gene flow and breeding systems of this important Acacia species

Observations on the biology of the South African checkered beetle Aphelochroa sanguinalis (Westwood) (Coleoptera: Cleridae)

The checkered beetle Aphelochroa sanguinalis (Westwood) (Coleoptera: Cleridae) is found in savanna and woodland ecosystems of southern and eastern Africa. During surveys for insect floral visitors in the Skukuza Ranger District of Kruger National Park, South Africa, we encountered adults of Aphelochroa sanguinalis on flowers of two tree species, Acacia grandicornuta Gerstner and Acacia tortilis (Forsskal) Hayne (Fabaceae). These two tree species flower in the early rainy season (November-December) and have small white flowers in small round ball-shaped clusters. Adults of phelochroa sanguinalis were not found on flowers of 14 other tree species with different floral structures which were flowering at the same time as Acacia grandicornuta and Acacia tortilis. Predatory, reproductive, and defensive behaviors (including the presence of a chemical defense) are described for Aphelochroa sanguinalis based on field and laboratory observations

Phyto-evaluation of Cd-Pb Using Tropical Plants in Soil-Leachate Conditions

Sources of soil contamination can exist in various types of conditions including in the form of semifluids. In this study, 3 different types of tropical plants, Acacia (Acacia mangium Willd), Mucuna (Mucuna bracteata DC. ex Kurz) and Vetiver (Vetiveria zizanioides L. Nash), were tested under different levels of soil-leachate conditions. The relative growth rate, metal tolerance, and phytoassessment of cadmium (Cd) and lead (Pb) accumulation in the roots and shoots were determined using flame atomic absorption spectrometry. Tolerance index, translocation factor, metal accumulation ratio, and percentage metal efficacy were applied to assess the metal translocation ability among all the 3 types of plants. Significantly higher (P \u3c .05) accumulation of Cd and Pb was exhibited in the roots and shoots of all 3 plants growing under the soil-leachate conditions. However, negative growth performance and plant withering were observed in both Acacia and Mucuna with increased application of higher soil-leachate levels. Vetiver accumulated remarkably higher total concentration of Cd (116.16-141.51 mg/kg) and Pb (156.37-365.27 mg/kg) compared with both Acacia and Mucuna. The overall accumulation trend of Cd and Pb in the 3 plants growing under the soil-leachate conditions was in the order of Vetiver \u3e Acacia \u3e Mucuna. The findings of the study suggest that Vetiver has great potential as Cd and Pb phytoremediator in soil-leachate conditions

L´impact des aires protégées et des utilisations anthropogènes du sol sur la regeneration des terrains boisés à Acacia dans l´est du Burkina Faso

Regeneration success, persistence strategies (seedlings vs. coppicing), and population trend of Acacia spp. were tested under two land-use regimes in eastern Burkina Faso: (i) protected areas shielded to livestock grazing pressure, to logging, and using early annual fire as a management system; (ii) areas with high human impact (heavily and extensive livestock grazing, harvesting for wood and for medicinal plants). Generally, a good regeneration rate of Acacia species was observed in protected areas and a poor regeneration rate in areas with high human impact. Nevertheless, some species affiliated to the subgenus Aculeiferum as A. dudgeoni and A. polyacantha showed a good regeneration under both land use regimes. Juvenile plants less than 25 cm height of A. dudgeoni and A. gourmaensis increased by 116 to 50 % in areas with human impact as compared to their populations in protected areas. With SCD slopes varying from –0.40 to -0.70, the protected Acacia woodland displayed a stable population structure due to abundance of recruitment, and coppicing persistence (more common in the subgenus Aculeiferum) favoured by early annual fire. Consequently, the protected areas are favourable for Acacia woodland regeneration. Conversely, SCD slopes are positive or close to zero in areas of anthropogenic regime and showed a declining population, especially more marked with the subgenus Acacia due to permanent seed and seedling removal by livestock grazing. Nevertheless, the number of seedlings of some species was higher in areas under human pressure than in protected areas, especially for the subgenus Aculeiferum, improving the genetic variability and thus the long-term maintenance of the population. Key words: Acacia, early fire, land use, sudano-sahelien zoneLe statut de la régénération, les stratégies de persistance et la dynamique des Acacia spp. ont été évalués suivant deux modes d’utilisation dans la région est du Burkina Faso: (i) les zones protégées soustraites du pâturage extensif et de la coupe du bois, mais sont parcourues annuellement par des feux précoces ; (ii) les zones à forte impact anthropique (fort pâturage extensif, exploitations humaines diverses). En général, les zones protégées montrent un taux de régénération élevé des Acacia spp. alors que les zones anthropogéniques présentent une faible régénération. Néanmoins, certaines espèces affiliées au sous genre Aculeiferum comme A. dudgeoni et A. polyacantha montrent une bonne régénération dans les deux modes d’utilisation des terres. La population juvénile de moins de 25 cm de hauteur des espèces tel que A. dudgeoni et A. gourmaensis est 116 à 50 % plus élevée dans les zones anthropisées que dans les zones protégées. Avec des pentes de régression variant entre -0.40 à -0.70 dans les zones protégées, les populations présentent une structure stable due à l’abondance des plantules, et des rejets de souches maintenues par les feux précoces (plus fréquent dans le sous genre Aculeiferum). Par conséquent, les zones protégées sont plus favorables à la régénération des formations d’Acacia. A l’opposé, les pentes de régression sont positives ou proche de 0 dans les zones anthropisées montrant des populations peu stables particulièrement pour le sous genre Acacia à cause du prélèvement des semences et des plantules due au pâturage extensif. Néanmoins, les plantules issues de la germination de certaines espèces du sous Aculeiferum sont plus nombreuses dans les zones anthropisées que dans les zones protégées et pourraient améliorer la variabilité génétique pour la conservation à long termes des peuplements. Key words: Acacia, feux précoces, pâturage, utilisation des terres, zone soudano-sahélienn

Uso das rúbricas de avaliación, a avaliación entre pares e a autoavaliación para mellorar as competencias do alumno

[Resumo] Na materia Sistemas de Abastecemento e Saneamento do Mestrado Internacional de Enxeñaría da Auga trabállanse as competencias transversais comunicativas, de consulta e selección de información e de avaliación crítica. Os alumnos realizan tarefas que consisten na revisión de referencias, a selección e organización de información e a presentación oral ou nun póster dun tema incluído nos contidos materia. Durante a presentación oral na clase, os alumnos dispoñerán dunha rúbrica na que deberán avaliar as presentacións dos seus compañeiros (avaliación entre pares) e despois a súa. Por último, a profesora avalía tamén a presentación. A nota final calcúlase a partir dos tres tipos de avaliacións e penalizarase aos estudantes que non realicen as avaliacións con rigor. Nestas actividades é fundamental que os criterios de avaliación sexan adecuados e que os alumnos os coñezan dende o inicio da actividade para dirixir o seu traballo. A avaliación entre pares fomenta que o alumno faga un esforzo para transmitir o mensaxe aos seus compañeiros. Por outra banda, obrígase indirectamente a prestar atención ao traballo dos compañeiros e, por tanto, apréndese dos contidos da materia. Na autoavaliación o alumno xulga os seu aprendizaxe e as súas fortalezas e debilidades na comunicación[Abstract] The transversal competences of communication, review and selection of references and critical assessment are practiced in the subject Systems of Supply and Sanitation of the International Master's in Water Engineering. Students carry out tasks that consist on the review of references, the selection and management of information and the oral or poster presentation about some of the subject contents. During the oral presentations, the students account for a rubric in which they have to evaluate the work of their peers (peer review) and their own work. Finally, the teacher also evaluates the presentation. The final mark is calculated from the three types of assessment and students who do not perform a rigorous assessment will be penalized. Appropriated assessment criteria that the students know from the beginning of the activity are required. Peer evaluation encourages students to make an effort to convey the message to their peers. On the other hand, they are indirectly obliged to pay attention to the presentations of their colleagues and, therefore, learn about contents of the subject. In the selfassessment the student judges their learning and their strengths and weaknesses in communication