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Marti-Herrero J.,Center Internacional Of Metodes Numerics En Enginyeria Cimne | Paco G.,Bolivian Catholic University | Zymla B.,German Society for International Cooperation | Heising K.,German Society for International Cooperation
Renewable Energy | Year: 2014

This paper presents the results and lessons learned from four and a half years of implementing low cost tubular digesters in Bolivia. The selection of this technology is justified in comparison with other popular technologies such as fixed dome or floating drum digesters. The highlighted weakness of the tubular model (its short life expectancy), is transformed into a strength, making the low cost tubular digester an appropriate technology for widespread application. The experiences in Bolivia show that the success of biogas programs depend more on socio-economic factors than on the validated technology selected, suggesting that local circumstances are a critical, and often underestimated, factor to be taken into consideration in the praxis. Finally, some testimonies of the use of biol (bio-slurry or effluent) are reported, identifying the high potential of this anaerobic digestion product that provides a food sovereignty approach, reduced expansion of the agricultural frontier, increased agricultural productivity and hence family income, that other household energizing systems do not have. A brief report of lessons learned is also included. © 2014 Elsevier Ltd.

Morales E.A.,Bolivian Catholic University | Morales E.A.,Higher University of San Simon | Morales E.A.,Academy of Natural Sciences of Philadelphia | Edlund M.B.,St. Croix Research | Spaulding S.A.,U.S. Geological Survey
Phycological Research | Year: 2010

Several populations identified and reported from North America and Mongolia under the names Fragilaria elliptica Schumann or Staurosira elliptica (Schumann) Williams et Round were analyzed in detail using light microscopy (LM) and scanning electron microscopy (SEM). The analysis yielded three variants that can not be ascribed to '. elliptica' of the type. Furthermore, two of the variants could not be related to published taxa and we describe them as new species, Staurosira ambigua sp. nov. and Staurosira dimorpha sp. nov. A third variant was identified as Pseudostaurosira trainorii Morales, a taxon originally reported from ponds and a river in the north-eastern USA. The combined LM and SEM analysis used here allowed for a more thorough circumscription of taxonomic boundaries among morphologically similar taxa and for better delimitation of their geographic distributions. A discussion of the taxonomy and ecology of these taxa based on literature and recent ecological data is presented. © 2010 Japanese Society of Phycology.

Wetzel C.E.,Center De Recherche Public Gabriel Lippmann | Wetzel C.E.,Institute Botanica | Morales E.A.,Bolivian Catholic University | Hinz F.,Alfred Wegener Institute for Polar and Marine Research | And 2 more authors.
Diatom Research | Year: 2013

The transfer of Fragilaria javanica Hustedt to the genus Fragilariforma D.M. Williams & Round is presented based on a detailed analysis of the type material from Java (Malay Archipelago) using light and scanning electron microscopy. The taxon is characterized by each areola covered externally with a rota, well-developed, simple apical pore fields composed of rounded poroids and located on both valve apices, denticulate spines with tips oriented towards the apices, and open girdle bands with valvocopulae bearing heavily silicified advalvar fimbriae. These features are all shared with species currently ascribed to Fragilariforma, although the spine shape and orientation, and girdle elements having two rows of areolae, along with valvocopulae with well-developed fimbriae are typical of F. javanica. Morphological, ecological and distribution data are presented and discussed based on available literature for this taxon. © 2013 The International Society for Diatom Research.

Morales E.A.,Bolivian Catholic University | Morales E.A.,Academy of Natural Sciences of Philadelphia | Novais M.H.,Center De Recherche Public Gabriel Lippmann | Chavez G.,Higher University of San Simon | And 2 more authors.
Fottea | Year: 2012

Three new araphid diatom species, Pseudostaurosira decipiens E. Morales, G. Chávez et Ector, P. sajamaensis E. Morales et Ector and Staurosira kjotsunarum E. Morales, Novais et Ector are described from a single sample taken from the Desaguadero River in the Bolivian Altiplano. These species clearly belong in their respective genera as evidenced by their morphological features studied using light (LM) and scanning electron microscopy (SEM). Pseudostaurosira decipiens is unique in its genus because of the combination of lanceolate-shaped valves with central area, well-developed spines lacking ligulae, siliceous deposits on outer and inner areolar openings similar to flaps, and the inner rounded structure of the apical pore fields. Pseudostaurosira sajamaensis is different from other species of Pseudostaurosira due to its elliptic to lanceolate valves bearing a wide central sternum, spines with developed ligulae and bilobed flaps, robust volae and reduced or absent apical pore fields. Staurosira kjotsunarum is unique within Staurosira in having elevated costae on both external and internal views, narrowly spatulate spines that hold onto areolae of neighboring valves along a chain, and striae composed of round poroids underneath the apical pore fields on the valve mantle. The three species are compared with morphologically similar taxa and a brief analysis of the richness found in the studied sample in the context of previous publications on diatoms from the Andes and contiguous regions is presented. © Czech Phycological Society (2012).

Faber-Langendoen D.,NatureServe | Keeler-Wolf T.,Biogeographic Data Branch | Meidinger D.,British Columbia Ministry of forests | Tart D.,U.S. Department of Agriculture | And 7 more authors.
Ecological Monographs | Year: 2014

A vegetation classification approach is needed that can describe the diversity of terrestrial ecosystems and their transformations over large time frames, span the full range of spatial and geographic scales across the globe, and provide knowledge of reference conditions and current states of ecosystems required to make decisions about conservation and resource management. We summarize the scientific basis for EcoVeg, a physiognomic-floristic-ecological classification approach that applies to existing vegetation, both cultural (planted and dominated by human processes) and natural (spontaneously formed and dominated by nonhuman ecological processes). The classification is based on a set of vegetation criteria, including physiognomy (growth forms, structure) and floristics (compositional similarity and characteristic species combinations), in conjunction with ecological characteristics, including site factors, disturbance, bioclimate, and biogeography. For natural vegetation, the rationale for the upper levels (formation types) is based on the relation between global-scale vegetation patterns and macroclimate, hydrology, and substrate. The rationale for the middle levels is based on scaling from regional formations (divisions) to regional floristic-physiognomic types (macrogroup and group) that respond to meso-scale biogeographic, climatic, disturbance, and site factors. Finally, the lower levels (alliance and association) are defined by detailed floristic composition that responds to local to regional topo-edaphic and disturbance gradients. For cultural vegetation, the rationale is similar, but types are based on distinctive vegetation physiognomy and floristics that reflect human activities. The hierarchy provides a structure that organizes regional/continental vegetation patterns in the context of global patterns. A formal nomenclature is provided, along with a descriptive template that provides the differentiating criteria for each type at all levels of the hierarchy. Formation types have been described for the globe; divisions and macrogroups for North America, Latin America and Africa; groups, alliances and associations for the United States, parts of Canada, Latin America and, in partnership with other classifications that share these levels, many other parts of the globe. © 2014 by the Ecological Society of America.

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