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Lattke J.E.,National University of Loja | Delsinne T.,Technical University of Loja
Myrmecological News | Year: 2016

Taxonomic clarifications and natural history data dealing with some species of the genus Gnamptogenys are offered: Gnamptogenys bufonis (MANN, 1926) is synonymized under G. simulans (EMERY, 1896); G. vriesi BRANDÃO & LATTKE, 1990 is redescribed and illustrated with SEM and montage images, the peculiar morphology of its compound eye is discussed. Also, an updated key for the G. minuta group species is presented and a nest of G. minuta (EMERY, 1896) is described. The species known up to now as G. costata (EMERY, 1889) is renamed G. coxalis (F. SMITH, 1857), and the species misidentified up to now as G. coxalis (ROGER, 1860) is renamed G. Sinhala LATTKE sp.n. Source

Mazon M.,University of Los Andes, Venezuela | Mazon M.,University of Alicante | Mazon M.,National University of Loja
Biodiversity and Conservation | Year: 2016

When trying to assess entomological diversity, identifying taxa at levels higher than species is much easier and may provide a wider vision of other ecological features. In this work, we used the data from several samplings made in across six cacao farms in Mérida state (Venezuela). Farms fell into two categories according to intensity of perturbation. In these samplings we identified all parasitoid Hymenoptera families. All individuals belonging to families Ichneumonidae, Braconidae and Chalcididae were sorted to subfamilies and then to morphospecies. The accuracy of subfamilies richness to predict the species richness and to detect differences in the conservation status of plantations was tested. The species aggregation according to the sampling size was also explored. The three families this study was focused on represented 23 % of the total sampling, comprising 40 subfamilies and 393 morphospecies. Results showed a significant high positive correlation between subfamilies and species richness, and species/subfamilies ratio was about 4.5:1, with logarithmic relationship with sampling size tending to stabilisation at sizes greater than 15 individuals per sampling day. Subfamily richness detected the nearly-significant differences in plantations with the same accuracy as species richness, and therefore surrogacy effectiveness of parasitoid Hymenoptera subfamilies richness may be accepted for cacao plantations. © 2015, Springer Science+Business Media Dordrecht. Source

Neill D.A.,Amazonian State University | Beltran H.,National Major San Marcos University | Quizhpe W.,National University of Loja
Novon | Year: 2012

Clethra concordia D. A. Neill, H. Beltrán & Quizhpe (Clethraceae), a thin-stemmed shrub or treelet from the sandstone Machinaza plateau in the Cordillera del Cóndor region on the Peru-Ecuador border, is described and illustrated. The new species is distinct from other species of Clethra L. in its small stature and its very small, thick sclerophyllous leaves, which are evidently an ecological adaptation to the highly acidic, nutrient-poor sandstone substrate where it occurs. Source

Volland F.,Friedrich - Alexander - University, Erlangen - Nuremberg | Pucha D.,National University of Loja | Brauning A.,Friedrich - Alexander - University, Erlangen - Nuremberg
Erdkunde | Year: 2016

Variations of stable oxygen isotopes in tree-ring cellulose are a widely used proxy to reconstruct hydro-climate variability in tropical and subtropical regions. We present the first δ18O chronology from annual tree rings in tropical Cedrela montana trees growing in the mountain rain forest of the Podocarpus National Park (PNP) in southern Ecuador. The more than a century long data record (1885-2011) comes from up to 15 individual trees (1980-2005) and represents the best- replicated isotope tree-ring chronology from the tropics. In comparison with tree-ring width, stable isotope variations show considerably higher correlations between individuals and thus represent a more reliable climate proxy in this very humid environment. High teleconnections to other stable isotope chronologies from the Amazon lowland indicate a high degree of consistency of regional hydro-climate variations. The PNP δ18O record is correlated with seasonal precipitation (January to April, CRU TS 3.21), frequency of wet days, and cloud cover over the Andean Cordillera Real. Spatial correlations indicate that the El Niño-Southern Oscillation (ENSO) has strong impact on tree-ring δ18O variations. Sea Surface Temperatures (SSTs) of the Niño 3.4 region and Niño 4 region, and the Oceanic Niño Index (ONI) show strong positive correlations with Cedrela oxygen isotope ratios, whereas the ENSO precipitation index correlates negatively. The Niño 3.4 and 4 SST influence is stronger after 1960 than before, indicating a shift in the influence of the Pacific Ocean on moisture variations in the Ecuadorian Andes. In the same period, the positive correlation with oxygen isotope signals from Andean glacier ice cores (r=0.2; p<0.05, 1894-1993) increased strongly (r=0.51; p<0.01, 1960-1993). In conclusion, stable oxygen isotope series from tropical tree species can help reconstruct variations in the hydroclimate of the Andean mountains and their surrounding areas. © 2016, Erdkunde. All rights reserved. Source

Wullaert H.,Johannes Gutenberg University Mainz | Homeier J.,University of Gottingen | Valarezo C.,National University of Loja | Wilcke W.,University of Bern
Forest Ecology and Management | Year: 2010

Atmospheric nitrogen (N) and phosphorus (P) depositions are expected to increase in the tropics as a consequence of increasing human activities in the next decades. In the literature, it is frequently assumed that tropical montane forests are N-limited, while tropical lowland forests are P-limited. In a low-level N and P addition experiment, we determined the short-term response of N and P cycles in a north Andean montane forest on Palaeozoic shists and metasandstones at an elevation of 2100m a.s.l. to increased N and P inputs. We evaluated experimental N, P and N+P additions (50kgha-1yr-1 of N, 10kgha-1yr-1 of P and 50kg+10kgha-1yr-1 of N and P, respectively) and an untreated control in a fourfold replicated randomized block design. We collected litter leachate, mineral soil solution (0.15 and 0.30m depths), throughfall and litterfall before the treatment began (August 2007) until 16 months after the first nutrient application (April 2009). Less than 10 and 1% of the applied N and P, respectively, leached below the organic layer which contained almost all roots and no significant leaching losses of N and P occurred to below 0.15m mineral soil depth. Deposited N and P from the atmosphere in dry and wet form were retained in the canopy of the control treatment using a canopy budget model. Nitrogen and P retention by the canopy were reduced and N and P fluxes in throughfall and litterfall increased in their respective treatments. The increase in N and P fluxes in throughfall after fertilization was equivalent to 2.5% of the applied N and 2% of the applied P. The fluxes of N and P in litterfall were up to 15% and 3%, respectively, higher in the N and N+P than in the control treatments. We conclude that the expected elevated N and P deposition in the tropics will be retained in the ecosystem, at least in the short term and hence, N and P concentrations in stream water will not increase. Our results suggest that in the studied tropical montane forest ecosystem on Palaeozoic bedrock, N and P are co-limiting the growth of organisms in the canopy and organic layer. © 2010 Elsevier B.V. Source

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